“A PROSPECTIVE STUDY OF VISUAL OUTCOME OF OPEN
GLOBE OCULAR INJURIES AT KIMS HUBLI”
BY
DR. RAVI SHANKAR M Dissertation submitted to the
RAJIV GANDHI UNIVERSITY OF HEALTH SCIENCES, KARNATAKA, BENGALURU.
In partial fulfillment of the requirements for the degree of MASTER OF SURGERY
In
OPHTHALMOLOGY Under the guidance of
Dr. UDAY SRIDHAR MULGUND M.S. ASSOCIATE PROFESSOR
DEPARTMENT OF OPHTHALMOLOGY KARNATAKA INSTITUTE OF MEDICAL SCIENCES HUBBALLI, 580021 2018
I
RAJIV GANDHI UNIVERSITY OF HEALTH SCTENCES,
KARNATAKA
DECLAITATIOI\ BY THE CAi\DIDATE
i herebr cieclare that tliis clissertation'thesis cntitied "A lrltOSPEC'l.tVE S'l'tlD\' ol" \'lStrAI- otr'l'(,oME ol.' OPL.N GLoIltr- oCULAR IN.IURIIIS A-t' KINIS llllBl.I" is a bonaflde ancl getruine research u,orli carried out br,me Lrncler the gttidiince o1' Dr. tIDAY SIIIDIIAR MtJLG[JNID. rr.s. Associate Profbssor. tr)cpartttrcttt o1'Ophthahrolosr'. Karnataka hrstitute of N{edical Scierrccs. Hubballi.
("; JLa-*-ka--r'' Date:.25f rolr+ - Dr. I{AVI SIIANI(AIi M
Place: HLrbballi. [)ost graclLratc stuc]ent- I)epartnrent of Ophthahlologr'.
Iian-ratalia InstitLrte of Medical Sciences Htrbballi. KARNATAKA INSTITUTE OF MEDICAL SCIENCES,
HUBBALLI.
CERTIFICATE BY THE GUIDE
This is to certify that the dissertation entitled "A PROSPECTM STUDY OF
VISUAL OUTCOME OF OPEN GLOBE OCULAR INJURIES AT KIMS
HUBLT" is a bonafide research work done by Dr. RAVI SHANKAR M in partial fulfi11ment of the requirement for degree of MASTER oF SURGERY in OPIITHALMOLOGY.
Date:.d.S-/LoltV Dr. UDAY SRIDHAR VIULGUND, nr.s. Place: Hubballi. Associate Professor, Department of Ophthahnology, I(an-rataka Institute of Medical Sciences, Hubballi. -.uoay ,rv Sridhuro',ri. Mulcund. Dr. i',r. o. r\1, s. Asscciate Prr'[cssttf ol OPirrn'i'mit;lS!' DePart'tnt tu K I tYl s' HU tlt'r'
ilt KARNATAKA INSTITUTE OF MEDTCAL SCIENCES, HUBBALLI
E]\DORSEMT]i\T BY THE HOD , PRIi\CIPAL/HEAD OF THE
I]\STITUTION
'l his is to cerlil'r'that the ciisseltation entitled ",\ PI{OSPEC'l'lVF. S'ftlD\'
OI.'\'[SI]AI, OU'I'COMIi OIi OPEN GI,ORE OCTII,AR INJLIRTES AT KIMS llUBLl" is a bonaticle research rvork clone br Dr. RAVI SIIANKAR NI. Lurcler the guiclance o1' Dr. tIDAY SRIDfIAR ivltll,Gt-lND. rr.s. Associate Ploltssor"
I)epartnrcnt ol'Ophthalnroloqr.Itarnatal,a InstitLrtc o1'\'leclica] Sciences. Hubballi. v --D- .-/Y{'^
f B BTTAJAN'I'*{, Dr. K. F. KAMMAR
Prol'essor aird I Ieac1. Principal,
Department Of Ophthalmology Karnataka Institute of Medical Sciences, Karnataka lnstitute of Medical Sciences Hubballi. HubbSi,efessor & HOt) PRINCIPAL. Iamalala Iustilute ol Medical Sclenq;, tiffi.$.:- HUBLI-22,
Dare: 26, lo'17 Date: a6l'olt+ Place : I-iubballi Place : HLrbballi COPY RIGHT
DECLARATTOT{ BY THE CANDIDATB
t l)r. RAVI SIIANKAR M, of KARNA'I'AI(A rNS'r'II'{rr.E oli MEDICAL s(lll'lN(ll'.S. IttrltllALLI, herebv cleclare that the Rajii Clanclhi Itniversitr o1'lJe.lth Sciences' I(arllataka shall ha'e Lhe right tci preserve. use ancl clissepipate the I)issertatiorlithesis ancl ;rrint in electronic torrnat fbr acaciemic/Research purpose.
o '(Aoin''" -f av't- '-' Ilare.4rf ia I tl Dr. I{AVI SIIANKAIT VI
Place: IJtrbballi. Postsraduate Str_rdent-
Department of Ophthaintologl .
Kalnatalia htstitute of Nlcclical Sciences HLrbballi.
O Rajiv Gandhi Universiff of Health Sciences, Karnataka. ACKNOWLEDGEMENT
The journey throughout the dissertation was a period of intense learning for me in many aspects which will be carried with me in my future.
At this point of the end of my dissertation, I would like to thank many people who were my support pillars and have helped and guided me throughout my journey.
My sincere gratitude to Dr UDAY SRIDHAR MULGUND n.s, Associate
Professor, Department of Ophthalmology, Karnataka Institute of Medical Sciences,
Hubballi for giving me all the necessary facilities to undertake my dissertation and I am extremely grateful to him as my guide, for his wisdom and excellent guidance. He has always taken out his precious time for me even in his busy schedule. He helped and encouraged me in every aspect to complete this work.
I take this opportunity to express my profound gratitude and deep regards to my beloved teacher Dr. Y B BHAJANTRI u.s, Professor and Head, Department of
Ophthalmology, Karnataka Institute of Medical Sciences, Hubballi, for his exemplary guidance, monitoring and constant encouragement throughout the course of this thesis. The blessing, help and guidance given by him time to time shall carry me a
long way in the journey of life.
I would also like to thank my teachers Dr Savitha Kanakpur, Dr Rajashekar Dyaberi, Dr SatishShet , Dr Venkataram Katti,
Dr Damayanthi, Dr Seethalakshmi, Dr Vivekananda jivanagi, Dr Varsha,
Dr Pooja, Dr Shobha and others who have helped and encouraged me to finish my
dissertation successfully My special thanks to my parents Mr Mahalingappa B V, Mrs Basammanni
B N , my son Kailash and my brother Dr Rajendra Prasad M and family , who always had faith in me and have supported me in my entire curriculum till date.
Without their hard work and struggle I would not be able to achieve and be the person who I am today.
I would like to thank all my patients who have given consent for this study without whom, this study would have been impossible.
I would like to acknowledge the constant help and support of my friends
Dr Deepthi, Dr Vidya, Dr Manohar, Dr Divya, Dr Jyothi, Dr Roopesh and Dr Roshan also my juniors Dr Vardhaman, Dr Abilash, Dr Akanth, Dr Mrudhula, Dr Polomi, Dr
Arpitha and others.
I would like to thank O T staff sisters Sunanda , Safinna ,brother Mohan and others
Department office staff Mahanthesh, Yellamma, Annapoorna who have all helped me whenever I needed, my humble thanks to them too.
,;) ('l- i-* k-, '' d-u )/' J' oate: QSf rcf >o t ? DT. RAVI SHANKAR M
Place: Hubballi. Postgraduate student,
Department of Ophthalmology,
Karnataka Institute of Medical Sciences,
Hubballi.
ii
“A PROSPECTIVE STUDY OF VISUAL OUTCOME OF OPEN GLOBE OCULAR INJURIES AT KIMS HUBLI”
LIST OF ABBREVIATIONS USED
Abbreviation Expansion
A S C O T A Severity Characterisation of Trauma
B E T T Birmingham Eye Trauma Terminology
I O F B Intra-Ocular Foreign Body
O T S Ocular Trauma Score
R A P D Relative Afferent Pupillary Defect
T R I S S Trauma and Injury Severity Score
V E P Visual-Evoked Potential
I S O T International Society for Ocular Trauma
W H O World Health Organisation
i
LIST OF TABLES
Page No. Tables No.
New standardized classification of ocular trauma 1. terminology 17
Ophthalmic effects of contusion or concussion 2. injury 21
International Society for Ocular Trauma classification 3. of an Open Globe Injury and closed globe injury. 48
OTS Score Variables with raw points at initial 4. examination 68
The OTS score and the patients probability of 5. attaining a specific visual acuity (determined from the raw score). 69
6. Graft materials in sclera patch graft. 92
7. Age distribution frequency. 103
Frequency table for the visual acuity at presentation, 8. presence of an afferent pupillary defect, zone of injury and type of injury 109
Visual outcome classified according to classification of 9. visual impairment by the World Health Organisation 112
10. Frequency table for the outcome measure. 112
i
Significance of age, sex, residence and relation to work 11. as a prognostic Factors 115
12. Significance of left or right eye as a prognostic factor 117
13. Significance of grade of injury as a prognostic factor 117
14. Significance of type of injury as a prognostic factor 118
15. Significance of zone of injury as a prognostic factor 118
16. Significance of pupil as a prognostic factor 119
17. Significance of length of wound as a prognostic factor 120
18. Significance of hyphaema as a prognostic factor 121
19. Significance of retinal status as a prognostic factor 121
Significance of delaying surgery more than 24 hours 20. as a prognostic factors 122
Significance of the requirement for a second surgery 21. as a prognostic Factor 123
Scoring system based on the ISOT classification of 22. open-globe injuries 124
Results of the scoring system using all the four factors 23. (grade, type, zone and pupil) 124
24. Pre operative Ocular trauma score OTS grades 125
25. OTS predicted final visual acuity of category 1 126
26. OTS predicted final visual acuity of category 2 127
ii
27. OTS predicted final visual acuity of category 3 127
28. OTS predicted final visual acuity of category 4 128
29. OTS predicted final visual acuity of category 5 128
Scoring system based on the ISOT classification of 30. open-globe injuries. 146
iii
LIST OF FIGURES
Page No. Photographs and Figures No.
Painting in the tomb of the master builder Ipwy at 1. Thebes 5
2. Bones forming orbital cavity 13
3. Left orbital roof fracture 23
4. An orbital blow out fracture of the floor of left orbit. 24
5. 7 rings of tissues that expand resulting in tears. 28
Overview of the terminology and classification of globe injuries accepted by the International Society of Ocular 6. Trauma. 45
7. Zone of injury for open globe injuries 49
8. Zone of injury for closed globe injuries 50
9. Corneal landmarks that facilitate anatomic realignment 79
Corneal suturing : The distance from the wound margin to the entry site (A) is the same as the distance from the 10. wound margin to the exit site(B) 81
11. Corneal Suturing of a shelved laceration 82
The box suture is a compromise structure for an 12. interrupted suture. 82
i
Sutures should be placed at right angles to the wound at 13. the point of the suture/wound inters section. 84
14. The Rowsey-Hays technique of central wound closure 84
The “Close as You Go” technique for Exploration and 15. Primary Closure of a Scleral Wound. 90
The anatomic Land marks identified in the 16. corneoscleral wound. 91
17. Granite foreign body in a stone cutting mason 99
18. Age distribution of thirty-eight patients (Bar chart) 104
19. Sex distribution of open globe injuries. (Pie chart) 105
Background distribution of open globe injuries. (Pie 20. chart) 105
21. Location of occurrence of injury (Bar chart) 106
22. Eye involved in injury (Pie chart) 108
23. Follow up vision (Pie Chart) 113
Significance of age, sex, residence and relation to work as a prognostic Factors (Bar Chart) showing final visual 24. acuity 115
Significance of left or right eye as a prognostic factor 25. (Bar chart) 117
Pre operative Ocular trauma score OTS grades (Bar 26. chart) 126
27. Zone 1 injury 129
ii
28. Lens disruption 129
29. Zone I injury with iris prolapsed 130
30. Zone I injury: Siedel’s Test – Positive 130
31. Globe Rupture with Phacocoele 131
32. Zone 2 injury with iris prolapsed 131
33. Zone 3 injury 132
34. Traumatic cataract 132
35. Subluxation of lens 132
Bar chart showing the outcome of the different grades of 36. injury 137
Bar chart showing the outcome with and without a 37. relative afferent pupillary defect 138
Bar chart showing the outcome of different types of 38. injury 139
Bar chart showing the outcome of different zones of 39. injury 141
iii
STRUCTURED ABSTRACT WITH KEY WORDS
“A PROSPECTIVE STUDY OF VISUAL OUTCOME OF OPEN GLOBE OCULAR INJURIES AT KIMS HUBLI”
Background and Objectives: Many factors that carry either a good or poor prognosis for visual outcome in open globe injuries have been studied in numerous retrospective studies in the past.
The recent classification of eye injuries accepted by the International Society of Ocular Trauma made the description of eye injuries less ambiguous, and has set the stage for prospective clinical studies.
To prospectively evaluate all patients with open globe injuries presenting to Karnataka institute of medical sciences Hubli over a one year period from January 2016 to December 2016 and study a list of factors with respect to the final visual outcome.
Methods: We evaluated the final visual acuity of thirty eight open globe injuries with a minimum follow-up period of six months. The anatomical and functional factors of each injury was analyzed with respect to the final visual outcome.
Results: We found that the factors that were statistically significant prognosticators of the final visual outcome were the grade of injury, afferent pupillary response, zone of injury, retinal detachment and wound length. Although the time interval of less than 24 hours between injury and surgery was associated with a better visual outcome, the association was found to be statistically significant.
Interpretation and Conclusion: We found that factors describing the functional status of the eye were more important in predicting the final outcome when compared to those related to the anatomy of the injury. We also established a pre-operative scoring system based on the internationally accepted factors used to classify an open-globe injury, which could accurately predict the visual outcome. Predicted the final visual outcome with ocular trauma score .
KEY WORDS
Cornea injuries ; Sclera injuries; Penetrating Eye Injuries ; Globe rupture ; Perforating eye injuries ; Eye Injuries classification ; Intraocular Foreign Bodies ; Trauma Severity Indices ;
Prospective Studies ; Ocular Trauma Score .
“A PROSPECTIVE STUDY OF VISUAL OUTCOME OF OPEN GLOBE
OCULAR INJURIES AT KIMS HUBLI”
INTRODUCTION
Vision is the most precious gift given by God and is the most cared for function of the human. This is possible only with healthy eyes.
An injury to the eye or its surrounding tissues is the most common cause for attendance at an eye hospital emergency department. The extent of trauma may range from simple superficial injuries to devastating penetrating injuries of the eyelids, lacrimal system, and the globe. The surgical management of such injuries is directed primarily at the restoration of normal ocular anatomy. The ultimate goal is to prevent secondary complications and maximize the patient’s visual prognosis.
The most significant cause of monocular blindness, globally is trauma.1,2 WHO stated that about 55 million eye injuries cause restriction of daily activities, among whom 1.6 million go blind every day.3 Ocular trauma counts for 7% of all bodily injuries and 10-15% of all diseases of eye.2 Ocular injuries represent 10-27% of cases examined in an outpatient department, 38-65% of cases in emergency department and 5-16% of admissions in eye hospitals.4 Ocular trauma results from redistribution of the incident energy, which affects both organic as well as inorganic tissues.5 Ocular trauma is preventable under certain precautions.6
Ocular trauma, not only, causes visual impairment, but also, is responsible for significant morbidity with relation to pain, psychosocial and financial stress.6 Different causative agents of ocular trauma are emerging and there is a change in epidemiology of ocular trauma depending
1 on many factors including population under study, location of injury, activity involved during injury, etc.4,7,8 Ocular injuries can be prevented and hence, it is necessary to understand the epidemiology and the risk factors for ocular trauma which can be avoided by increasing the awareness within the local population. This data regarding the Indian population is scarce and actual prevalence of ocular trauma in India is not known.3
There are controversies regarding the management of severely traumatized eyes, particularly the approach towards the condition. Hence, it is important to study the functional outcome of patients with severe ocular trauma. This will prove as an important guide to predict the prognosis of patients with severe ocular trauma. There is lack of data about the prediction of functional outcome by use of ocular trauma score established by Kuhn et al in Indian patients.
Ocular injuries (both open globe and closed globe) are relatively common, but open globe injuries more often result in a poor visual outcome.9
Kuhn et al (2002) analysed the evidence on several factors of prognostic importance in mechanical eye injuries.10 The factors studied were age, sex, laterality of eye injured, cause of injury, type of injury, facial fractures, initial visual acuity, wound location, extent of wound, hyphaema, intraocular foreign body, presence or absence lens injury, retinal detachment, vitreous haemorrhage tissue prolapse, VEP and ERG. They noted that studies on these prognostic factors are difficult to interpret as they often give contradicting results or have different cut off values for the same factor.
Kuhn F et al (2002) analysed over a hundred factors in 2500 injured eyes to judge the prognostic value of each of them.11 Of the variables analysed, only a few were found to be reliable in predicting the long-term visual acuity as well as being easy to determine during initial
2 clinical examination or surgery. These factors were found to be initial visual acuity, type of injury (with more significance to rupture and perforating injuries), the presence of an afferent pupillary defect, the presence of a retinal detachment and the presence of endophthalmitis. The zone (posterior extent) of injury is also an important criteria in the prognosis as posterior injuries generally carry a graver prognosis.12 Literature shows that visual acuity at the time of presentation and the presence of a relative afferent pupillary defect are the most accurate predictors of visual outcome.13,14,15
Until recently, studies on ocular trauma were plagued by the lack of a common language to share eye injury information. A standard for this has been suggested by Kuhn and associates16,
17 in 1996 and adopted by the International Society of Ocular Trauma in1997.18This has made classification of eye injuries less ambiguous, and has set the stage for prospective clinical studies to evaluate the efficacy of current or future treatment modalities. Our study strives to meet that demand, as most of the previous studies which evaluate the factors affecting the visual outcome of open globe injuries have been retrospective and non-comparative. This study aimed at studying the epidemiology regarding the causes and risk factors of open globe ocular trauma with emphasis on the functional outcome of patients with open globe ocular injuries.
3
AIMS AND OBJECTIVES
AIMS
A. To study the causation and management of Open globe injuries.
B. To evaluate the final visual outcome and sequelae of Open globe injuries.
OBJECTIVES
• To study various functional and anatomical factors of an open globe injury with respect to
the final visual outcome, as recorded by the last visual acuity after 6 months of the injury
• To use probability models to determine which of those factors correlate best to the final
visual outcome.
• To study various factors of treatment modalities (such as time of initial repair and necessity
for a second surgical procedure) with respect to the final visual outcome.
• To suggest an approach to improve the prognosis for open globe injuries.
4
REVIEW OF LITERATURE
Historical review
The history of Ocular Injuries began when one primitive man fought with the another. When he first walked through forest and chipped a flint to make his primitive tool. At a much later date, that is about the year 1200 BC. One artist painted a picture of removal of foreign body from the eye of a workman on a tomb.
Figure 1: Painting in the tomb of the master builder Ipwy at Thebes
Sir.William Tindall Lister (1868-1944) has contributed most richly to the knowledge of ocular injuries.
5
The earliest statistics of the incidence of Ocular trauma of all types among ophthalmic patients were correlated by Zander and Geissler19(1864) they found the estimate to vary from 1.8 to 9% of all eye diseases.
In subsequent studies the figures have varied Weidmann20 (1888) among
30,000 ophthalmic patients he found total incidence of 4.89%. According to Arnold
Sorsby21 (1972) the incidence is 10% in non Industrial areas and 30 to 50% in the
Industrial Areas.
Epidemiology of Eye Trauma
Shukla and Verma (1979) conducted a clinical study of ocular injuries in
Raipur (India).22They found that the third decade was the most common age for ocular injuries. Males formed 83.25% of the study group. Perforating injuries accounted for 12.5% of the injuries (including injuries with a foreign body). An analytical study of ocular injuries by Jain and Soni (1987) in Jansi (India) found that
63% of those injured were between 16 and 30 years of age and 61% were male.23Perforating injuries accounted for 26% of the injuries.
In a retrospective study conducted in Los Angeles, USA by Liggett et al
(1990) at a large metropolitan hospital during a six-month period, the demographic and clinical data on 1132 patients of ocular and adnexal trauma were studied.24 Most of patients analyzed were in the first 3 decades of life, peaking at the age of 21 to 25 years. They found that 82% of those injured were males.
Voon LW et al The epidemiology of ocular trauma in Singapore; Perspective from the emergency service of a large tertiary hospital 25prospective survey was conducted over a 3 month period (August to October 1997) on all patients seen at the 6 ophthalmic unit at the Singapore General Hospital's emergency service. Data on clinical presentation, type and cause of injury and use of eye protective devices (EPD) were collected via a standardized interview and examination. A total of 870 persons presented with a diagnosis of ocular trauma, out of the 1631 patients seen during the study period. Compared with non-trauma cases, trauma cases were more likely to be male (odds ratio (OR): 4.2, 95% confidence interval (95% CI): 3.2, 5.4), non- residents (OR: 6.2 , 95% CI: 3.7, 10.5), younger than 40 years of age (OR: 3.2, 95%
CI: 2.7, 4.1) and less likely to require follow-up or hospital admission (OR: 0.2, 95%
CI: 0.2, 0.3). The three most common types of injuries were superficial foreign body
(58.2%), corneal abrasion (24.9%) and blunt trauma (12.6%), while open globe injury occurred in only 17 cases (2%). Comparison with a 10% random sample of all cases seen in the previous 9 months (n = 284) revealed no significant time variation in the types of injuries (p = 0.63). Work-related injuries accounted for 590 (71.4%) cases, where grinding, cutting metal and drilling were the specific activities in more than
90% of the cases. In appropriate settings, only 21.7% of patients with work-related injuries used EPD; 43.7% were provided with EPD, but did not use them at the time of injury; and the remaining 34.6% reported that EPD were not provided. Concluded that Ocular trauma at the emergency service level in Singapore involved mainly young non-resident men, were work-related and associated with well-defined activities, and were generally minor. The low prevalence of EPD use reinforces the need for a review of the design and implementation of occupational eye safety programmes, especially among non-resident workers.
Ocular trauma is also an important cause for ocular morbidity in South India.
Dandona L et al (2000)26 published the results of the population-based Andhra
7
Pradesh Eye Disease Study which showed that ocular trauma affects one in 25 people in the urban population in South India, and one in 167 people in this population are estimated to be blind in at least one eye due to trauma. The Aravind Comprehensive
Eye Survey, a population-based South Indian study by Nirmalan et al
(2004),27showed that the lifetime prevalence of ocular trauma is higher than that reported for glaucoma, age-related macular degeneration, or diabetic retinopathy from this population.
Visual Outcome in Open Globe Injuries
Although ocular trauma is still a leading cause for visual loss in the world, many authors have pointed to an improved prognosis over the last few decades.12
Snell in 1945 reported that only 30% of the injuries resulted in a visual acuity of 6/12 or better.28 With the advent of microsurgical techniques, Eagling (1976) reported that
62% of those with open globe injuries resulted in a final visual acuity of at least
6/12.29Vitreoretinal surgical techniques were introduced in the 1970‟s and de Juan et al (1983) reported that 71% of patients with penetrating injuries had a final visual acuity of 6/18 or better.30
In a study of the surgical results in posterior segment ocular injuries, Brinton et al (1982) found that out of the 106 eyes studied only 55 eyes (52%) achieved functional success (defined as a final visual acuity of 6/30 [20/100] or better or as a postoperative improvement in visual acuity from light perception or worse to 6/240
[5/200] or better), 16 (15%) attained anatomic success (attached retinas and generally clear media) but were functional failures, and 35 (33%) were both anatomic and functional failures.31
8
Krishnan and Srinivasan (1988) studied the visual outcome of 309 patients hospitalised with ocular injuries in Pondicherry (South India).32 They studied 77 cases of blunt injuries and 173 cases of perforating injuries and found that 70% of the penetrating injuries had a vision worse than 6/60 when compared to 62% of the blunt injuries. In a South Indian study by Gothwal et al (1999) it was reported that with the present microsurgical capabilities, prompt and meticulous surgical treatment restored vision to 6/18 or better in 60.5% of patients.33
Rahman et al. Open globe injuries: factors predictive of poor outcome .Repair of an open globe injury from 1 January 1998 to 1 January 2003 at the Manchester Royal
Eye Hospital. Case notes were examined to determine demographic data, mechanisms of injury, influence of alcohol/drugs, and location of injury. The Snellen visual acuity on presentation and initial clinical signs were recorded. In total, 115 cases of open globe injury were identified of which 107 cases notes were available for review.
Injury to the eye with a sharp object accounted for 71/107 (66%) and blunt mechanisms for 30/107 (28%) cases. In six (6%) cases the cause of injury was unknown. The rate of secondary enucleation in our series of 107 open globe injuries was 13/107 (12%). Significant risk factors on presentation associated with eventual enucleation included relative afferent pupillary defect (P<0.001), absence of a red reflex (P<0.001), presence of a lid laceration (P<0.02), a blunt mechanism of injury
(P<0.02), and an initial VA worse than 6/60 (P=0.03). Concluded that from this retrospective study, have identified several factors that may aid the clinician in deciding on the prognostic value of primary repair. Blunt injuries associated with adnexal trauma, with poor initial visual acuity, the presence of an RAPD or retinal
9 detachment, and the absence of a red reflex are associated with a significantly higher rate of subsequent enucleation34.
In study done by university of cape town and groote schuur hospital,south
Africa.visual outcomes as a result of time delays from trauma to surgery in cases of open globe injuries ,conclussion was the mean time from injury to surgical treatment was around 3.3 days for all cases (median 2.125days).only zone 1 injuries with surgery delayed beyond 72 hours had worse outcomes
Sharma T, Agarwal P, Gopal L, Badrinath S S, Murugesan R at Vision
Research Foundation, Madras, studied 100 children with penetrating injury with broomstick bows and arrows. They found that successful reconstruction of the globe with attached retina was attained in 85% of the eyes. Improvement in visual acuity of two Snellen lines in eyes with measurable pre operative acuity or improvement to at least 2 / 60 with pre operative acuity of PL or HM, was attained in 62% of the eyes; acuity of 6/9 or better was achieved in 28%. Predictors of poor anatomical success were injuries involving both anterior and posterior segment, endophthalmitis and presence of retinal detachment.35
In a study done by Imtiaz A, Choudhry et al, who studied visual outcome of endophthalmitis associated with IOFB, it was found that delayed removal of IOFB following trauma significantly increased the chances of endophthalmitis.36
Purkayastha S et al reported that the institution of prompt treatment of open- globe injuries has an important effect on the final outcome. An open eye should be repaired as soon as possible and repair of a rupture or penetrating wound should always be attempted.37
10
A Prospective observational study done by Dr lavanya g rao institute of ophthalmology ,Kasturba medical college ,Manipal, India, on ocular survival ,visual outcome and prognostic factors in open globe injuries. This was a prospective observational study of 80 cases of penetrating trauma which presented to our hospital between November 2004 and August 2006. Relevant history included patient details, mechanism, and time since injury. Examination was done to detect initial visual acuity (Snellen's acuity), length of wound, zone of injury, presence of iris prolapse, afferent pupillary defect, cataract, hyphema, retinal detachment, vitreous hemorrhage, intraocular foreign body. These factors were categorized according to ocular trauma classification system. Primary repair was done under general anesthesia. Patients were reviewed at one, three and six months. Assessment included best corrected visual acuity, wound status, intraocular pressure (IOP), fundus examination and B- scan ultrasonography. Final visual acuity was graded according to World Health
Organization (WHO) visual impairment categories: ≥ 20/70, (good visual outcome),
<20/70 – 20/200, <20/200 – 20/400, <20/400 (low visual outcome) Eleven eyes were lost to follow-up and 69 eyes were included for statistical analysis. Eight eyes had only one month follow-up. Univariate analysis was done using Chi Square test, multivariate analysis was done to find prognostic significance. P value <0.05 was considered significant 38 concluded ocular survival was 97%.initial visual acuity, hyphema, zone and length of injury ,retinal detachment and vitreous hemorrhage are statistically significant factors affecting outcome in open globe injuries.
Zhang et al Endophthalmitis following open globe injury 39The study post- traumatic endophthalmitis following open-globe injury and identify factors affecting its frequency in order to gain further knowledge about possible risk factors for the
11 development of endophthalmitis. open globe injury cases (4968 eyes in 4865 inpatients) in 15 tertiary referral hospitals in China over 5 years (January 2001 to
December 2005) were retrospectively reviewed. The information was collected from a standardised database of eye injuries from which a detailed analysis of factors influencing the incidence of endophthalmitis was performed. Concluded that early primary repair, tissue prolapse and self-sealing of wounds are independent protective factors against the development of endophthalmitis following open-globe injuries.39.
CLINICAL ANATOMY OF THE EYE
The eye is a delicate sense organ that is surrounded by specialized structures and protected by the bony orbit, soft tissue, and eyelids. The globe itself is composed of three primary layers or “coats”: the sclera, the uvea, and the retina. Anteriorly, the cornea covers the central area of the eye, and the conjunctiva covers the sclera. The iris, the ciliary body, and the choroid constitute the uvea. The crystalline lens separates the anterior and posterior chambers from the vitreous body. The optic nerve transmits images from the retina to the brain.
Clinical Anatomy of the orbit
The orbit is a four-sided conical structure with its base directed forwards and apex projecting medially towards the optic foramen. The base or the orbital rim is outlined by thick strong bone: the supra-orbital arch of the Frontal bone above, the
Zygoma and Maxilla inferiorly, the Zygoma laterally and the frontal process of the
Maxilla medially. The walls of the orbit consist of relatively thin bone. The orbital volume is about 30ml and the orbital depth is approximately 4.5cm. Consequently slight change in the bony orbit will be reflected on soft tissue and globe position.
12
Figure 2: Bones forming orbital cavity
Orbital Bones contributing to each wall
Roof
• Frontal bone
• Lesser wing of the Sphenoid bone
Medial wall
• Frontal process of the Maxillary bone
• Lacrimal bone
• Ethmoid bone
• Body of the Sphenoid bone
Floor
13
• Maxillary bone
• Zygomatic bone
• Palatine bone
Lateral Wall
• Zygomatic bone
• Greater wing of Sphenoid bone
Eye lids
The eyelids protect the surface of the eye and also contain glands that
contribute components to the tear film. The upper eyelid can be divided into two
lamellae:
Anterior: Skin, orbicularis.
Posterior: Tarsus, levator aponeurosis, Muller‟s muscle, palpebral conjunctiva.
Conjunctiva
The conjunctiva is a clear, vascular, mucous membrane composed of non-
keratinized epithelium with goblet cells and underlying loose stromal tissue.
Conjunctiva is divided into:
i. The Bulbar conjunctiva – covers the anterior sclera and is loosely adherent except
at its attachment to the corneo-scleral junction, where it fuses with Tenon‟s capsule.
14 ii. The Palpebral (or Tarsal) conjunctiva-- covers the inner surface of the eyelids, where it is firmly attached to the tarsal plates. iii. The Fornices (Superior fornix and inferior fornix) are blind pouches where the conjunctiva reflects upon itself between the bulbar and palpebral surfaces.
Sclera
The sclera is the tough, avascular, outer fibrous layer of the eye that forms a protective coating. It is composed of dense collagen fibrils that are not highly organized. The sclera is covered by fascia and conjunctiva anteriorly and fat posteriorly.
Uvea
The uvea refers to the pigmented layer of the eye and is made up of three distinct structures: the iris, the ciliary body, and the choroid.
The iris divides the anterior chamber and the posterior chamber. The ciliary body is the 6mm portion of uvea between the iris and choroid, and is attached to the sclera at the scleral spur. It is composed of two zones, the anterior 2mm pars plicata, which contains the ciliary muscles, vessels and processes, and the posterior 4mm pars plana.
The choroid is the tissue between the sclera and the retina, and is attached to the sclera at the optic nerve and scleral spur. This highly vascular tissue supplies nutrition to the RPE and outer retinal layers.
Lens
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The crystalline lens, located between the posterior chamber and the vitreous cavity, separates the anterior and posterior segments of the eye. The lens grows by elongation and transformation of the epithelial cells into lens fibers.
Vitreous
The vitreous humour is a viscous, gel like substance that fills the posterior segment of the eye between the lens and the retina. The vitreous is composed mainly of water, but also contains collagen fibers, mucopolysaccharides and hyaluronic acid.
Retina
The retina is the delicate transparent light sensing inner layer of the eye that functions like film in a camera. Light travels through the retina to the photoreceptors in the outermost layer. The rod and cone photoreceptor cells convert the light into neural signals that pass back through the retina to the ganglion cells whose axons form the optic nerve.
Optic nerve
The optic nerve is essentially a cable of many wires that transmits images from the eye to the brain where they can be interpreted. The nerve contains approximately 1.2 million axons formed from the retinal ganglion cells in the retina and appears as a yellow – orange circle, nasal to the fovea.
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NEW STANDARDIZED CLASSIFICATION OF OCULAR TRAUMA
TERMINOLOGY
Term Definition
Eye wall Sclera and cornea
The eye wall does not have a full thickness wound (eye Closed-globe injury wall not opened).
Open globe injury The eye wall does have a full thickness wound.
Full thickness eye wall wound caused by a blunt object.
The impact results in a momentary increase of IOP and Rupture an inside-out mechanism.
Full thickness wound of the eye wall usually caused by a sharp object. The wound occurs at the impact site by Laceration an outside-in mechanism.
Single laceration of the eye wall, usually caused by a Penetrating injury sharp object.
Intra-ocular foreign body Retained foreign object(s) causing entrance (IO-FB) laceration(s).
Two full thickness lacerations (entrance plus exit) of Perforating injury eye wall usually caused by sharp objects as missiles.
Table 1: New standardized classification of ocular trauma terminology
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OCULAR MANIFESTATIONS OF TRAUMA
Injury to the eye lid may be divided into blunt or penetrating trauma.
Blunt Trauma
Ecchymosis and edema are the most common presenting signs of blunt trauma. A haematoma (black eye) is the most common result of blunt injury to the eyelid or forehead and is generally innocuous.
Penetrating Trauma
These can be classified as: i. Laceration not involving eye lid margin ii. Laceration involving the eye lid margin
Superficial eyelid laceration involving just the skin and orbicularis muscle usually require only skin suture. The presence of orbital fat in the wound means that the orbital septum has been violated. Superficial or deep foreign bodies should be searched for meticulously before these deeper eyelid lacerations are repaired. Copious irrigation lavages away contaminated material in the wound. Orbital fat prolapse in the upper eyelid wound is an indication for levator exploration.
Trauma involving the canthal soft tissue
Trauma to the medial or lateral canthal areas is usually the result of horizontal traction on the eyelid, causing eye lid avulsion at its weakest point, the medial or lateral canthal tendon.
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Lacerations in the medial canthal area demand evaluation of the lacrimal drainage apparatus, which is always involved in an avulsion injury. Canalicular involvement is usually confirmed by inspection and gentle probing. Trivial medial canthal injuries result in canalicular lacerations.
Contusion and concussion injury
Concussion occurs due to sudden acceleration or deceleration imparted by impact of a blunt force sustained by a blow from a large object or in a collision or fall. Concussion indicates that there is no disorganization of tissue and the changes are reversible. Contusion injury indicates there is disorganization of tissues, like bruising, perivascular haemorrhage etc, with intact surface integument.
As a general rule, either the anterior segment of the eye in front of the iris-lens diaphragm, or the posterior half is preferentially affected.
Mechanism of concussion injury
When a force impinges upon the cornea this tissue is thrust inwards and may even be forced against the lens and iris, the wave of aqueous pushes these structures backwards, the compression wave rebounds from the back of the eye and they are thrust forward again. They may thus be severely traumatized.At the same time, there is a horizontal wave of pressure striking the retina and choroid as well as the angle of the anterior chamber, which may do considerable damage.
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Ophthalmic effects of contusion or concussion injury
Ocular tissue involved Clinical manifestations
Orbit Blowout fracture of medial wall or floor
Orbital haematoma
Carotid – cavernous fistula
Eye lids Haematoma
Avulsion of the lower lid
Conjunctiva Subconjutival haemorrhage
Anterior uvea Hyphaema
Tears of the iris sphincter and iridodiolysis
• Angle recession and cyclodialysis
Lens • Rosette cataract
• Subluxation of the lens
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• Rupture of the anterior or posterior capsule
Sclera • Rupture, commonly at the limbus or behind the
insertion of the recti
Vitreous • Haemorrhage
Choroid • Choroidal rupture
• Suprachoroidalhaemorrhage
Retina • Retinal or subretinalhaemorrhage
• Retinal oedema, commotio retinae
• Retinal dialysis
• Macular oedema or hole
Optic nerve • Optic nerve avulsion
• Haemorrhage of the optic nerve sheath.
Table 2: Ophthalmic effects of contusion or concussion injury
21
Orbital fractures
Orbital trauma can damage both the facial bones and the adjacent soft tissue.
Fractures may be associated with injuries to orbital contents, intracranial structures, and paranasal sinuses.
Zygomatic fractures
Zygomatico – maxillary complex fractures are called tripod fractures, although the Zygoma is usually fractured at four of its articulations with the adjacent bones
(Lateral orbital rim, Zygomatic arch, and lateral wall of the maxillary sinus). The zygomatico – maxillary complex fracture involves the orbital floor to varying degrees.
Orbital Apex Fractures
Orbital Apex fractures usually occur in association with other fractures of the face, orbit, or skull and may involve the optic canal, superior orbital fissure, and structures that pass through them. Possible associated complications include damage to the optic nerves with decreased visual acuity, cerebrospinal fluid leaks, and carotid cavernous sinus fistula.
Orbital roof fractures
Orbital roof fractures are usually caused by blunt trauma and are more common in young children who do not yet have pneumatized frontal sinus. Frontal trauma in older patients tends to be absorbed by the frontal sinus, which acts as a crumple zone, preventing extension along the orbital roof. Complications include
22 intracranial injuries, cerebrospinal fluid rhinorrhea, pneumocephalus, subperiosteal hematoma, ptosis, and extraocular muscle imbalance.
Figure 3 : Coronal ( A ) and oblique sagittal ( B ) reformations show cranial displacement of left orbital roof fracture fragment ( arrows ). Note pneumocephalus ( dotted arrows ) implying violation of the dura.
MEDIAL ORBITAL FRACTURES
Direct (Naso-orbital – ethmoidal) fractures
These fractures result from the force striking solid surfaces. These fractures commonly involve the frontal process of maxilla, the lacrimal bone, and the ethmoid bones along the medial wall of the orbit. Patients characteristically have a depressed bridge of the nose and traumatic telecanthus.
Indirect (blowout) fractures
These are frequently extensions of blow out fractures of the orbital floor.
Isolated blowout fractures of the medial orbital wall also may occur. Emphysema of the eyelids and orbit is commonly associated with fractures of the medial orbital wall.
23
The risk of enophthalmos is greatest when both the floor and the medial wall are fractured and displaced.
Orbital floor fractures
Direct fractures of the orbital floor can extend from fractures of the inferior orbital rim. Indirect fractures of the orbital floor are not associated with fracture of the inferior orbital rim
Figure 4 : An orbital blow out fracture of the floor of left orbit.
Past theory held that blow out fractures resulted from sudden increase in intraorbital pressure resulting from the application of force by a non penetrating object, usually smaller in diameter than the orbital entrance. According to this theory, the contents of the orbit are compressed posteriorly towards the apex of the orbit and the orbital bones break at their weakest point, usually the posterior medial part of the floor in the maxillary bone. The orbital contents may be entrapped or may prolapse through the fracture in the maxillary sinus. A more recent theory, however, is that the striking object causes a compressive force at the inferior rim, which leads directly to buckling of the orbital floor. The degree of increased orbital pressure determines 24 whether or not orbital contents are pushed down through the fracture into the maxillary antrum.
The patient may present with
1. Eyelid signs: Ecchymosis and edema of the eyelids may be seen, but external
signs of injury can be absent.
2. Diplopia with limitation on upgaze, downgaze, or both.
3. Enophthalmos of the globe and ptosis.
4. Hypoaestheisa in the distribution of the infra orbital nerve.
5. Emphysema of the orbit and eyelids.
Conjunctiva
A blunt injury may produce subconjuctival haemorrhages, chemosis or lacerations of the conjunctiva. But in mild injury, no damage is done.
Sub-conjunctival Haemorrhage
Following an injury, the blood vessels of the conjunctiva are torn, giving rise to bleeding into the sub conjunctival tissues. The haemorrhage may vary in size, from a petechiae to a large extravasation. Sometimes, producing a “bag of blood” appearance protruding over the lid margin. The haemorrhage frequently occurs in the bulbar conjunctiva, and rarely in the palpebral area, because of the anatomical predisposition. A subconjunctival haemorrhage frequently conceals a scleral rupture.
The extent of sub-conjunctival haemorrhage is graded by dividing the area of bulbar conjunctiva into 4 quadrants.
25
Grade I: Haemorrhage involving one quadrant
Grade II: Haemorrhage involving two quadrants
Grade III: Haemorrhage involving three quadrants
Grade IV: Haemorrhage involving four quadrants
This grading is described by R.C.Gupta.
Chemosis
It occurs rarely. There is an accumulation of transudate in the sub-conjunctival tissue. The conjunctiva then bulges, and may even fold over the cornea, or protrude between the lids.
Conjunctival laceration
The conjunctiva is very thin and gets lacerated following a direct impact. This is rarely extensive, as conjunctiva is freely mobile.
Cornea
Corneal abrasion involves a breach of the epithelium, which stains with fluorescein. If over the pupillary area, vision may be grossly impaired. This is an exquisitely painful condition.
Blunt Trauma
Although blunt injury of insufficient force to rupture the globe can cause severe intraocular damage, its effects on the cornea are usually transient. A direct, focal, concussive blow causes mechanical deformation injury to the surrounding 26 endothelium, evident as a ring of corneal edema. Such localized contusion resolves with recovery of the injured cells or their replacement by adjacent endothelium. In more severe corneal contusion, ruptures of Descemet‟s membrane with concomitant breach of the endothelial barrier result in acute hydrops with massive stromal edema.Although the decrease in vision and the acute appearance of corneal edema may be capable of healing such defects by sliding over the area of retracted
Descemet‟s membrane and restoring the normal endothelial pump and barrier to maintain corneal deturgescence. Specular microscopy of the corneal endothelium after blunt trauma may reveal a significant decrease in the endothelial cell population and increased cellular pleomorphism compared to the fellow eye.
Corneal rupture is an uncommon consequence of blunt trauma and typically occurs only in eyes predisposed by a corneal stromal thinning disorder, such as extreme Terrien‟s marginal degeneration, or by prior surgery such as Keratoplasty or radial keratotomy.
Dante J Pieramici, Leonard M parver (1995) stated that there are 7 rings of tissues that expand resulting in tears.
1. Sphincter pupillae
2. Iris base to Ciliary body.
3. Anterior face of ciliary body.
4. Attachment of ciliary body to scleral spur.
5. Trabecular mesh work.
6. Lens Zonules
7. Attachment of vitreous and retina
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Figure 5: 7 rings of tissues that expand resulting in tears.
Traumatic Hyphaema
An accumulation of blood in the anterior chamber is known as hyphaema.
Trauma producing bleeding into the anterior chamber of the eye is common.
Hyphaema can be primary, secondary and recurrent.
Primary Hyphaema
It occurs at the time of the injury. The bleeding is self – limiting, irrespective of whether it occurs from a small vessel or a large vessel. This is because
1. Equilibrium is maintained between the vascular and the intraocular pressure.
2. Once a vessel of the iris ruptures, there is immediate contraction of its wall. This is also the reason why there is no bleeding following an iridectomy. If the haemorrhage
28 is large, it suggests that a larger size vessel near the root of the iris or, in the ciliary body is torn.
Secondary Hyphaema
Following an injury at the onset, there may not be any haemorrhage. But, the haemorrhage occurs on the 2nd to 5th day. Secondary haemorrhages usually produce small hyphaemas. Incidence of secondary haemorrhage is variable: 5% to 30%19.
Secondary haemorrhage is more common when the amount of blood initially is large.
Recurrent Hyphaema
Rarely, haemorrhage into the anterior chamber recurs for weeks or months.
Recurrent hyphaema following a blunt injury to the eye may at times be associated with a more severe prognosis than occurring from the initial trauma.
The complications which can develop are : higher risk of secondary glaucoma, corneal blood staining, poor visual activity.
The presence of fresh blood in the anterior chamber, or an increase in the amount of blood in the anterior chamber is considered indicative of a recurrent bleeding. The risk factors which are associated with the development of recurrent haemorrhage are not well defined, and the exact mechanism is not known. It is hypothesized, that, once the initial vasospasm is relieved or after fibrinolysis occurs, the platelets can no longer adhere to the vessel wall or cannot aggregate without the persistence of the tissue pressure found else where in the solid tissue of the body. The initial clot which is formed is expressed into the low – resistance anterior chamber producing further haemorrhage.
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Grading scheme for traumatic Hyphaema
Grade Size of hyphaema (fraction of anterior chamber filled with blood)
I < 1/3
II 1/3 – ½
III ½ - near total
IV Total (Eight –ball)
Associated ocular findings
Angle recession, a separation between the longitudinal and circular muscle fibres of the ciliary muscle, is the most important associated anterior segment finding in traumatic hyphaema The amount of angle recession does not necessarily correlate with the size of the hyphaema or degree of acute IOP elevation. The incidence of angle recession is variably reported as 30% to 85%.
More extensive recession is associated with a higher incidence of late onset glaucoma, and it is estimated that approximately 6% to 10% of hyphaema patients will develop angle recession glaucoma.
A cyclodialysis cleft with separation of the scleral spur from its ciliary body attachments occurs less commonly and may cause post injury hypotony.
Traumatic iritis invariably accompanies hyphaema. Furthermore, pigment liberation may result in endothelial pigment dusting and increases trabecular meshwork pigmentation. Iris atrophy occurs less commonly, and a Vossius ring, signifying compression of the pupillary margin on the anterior lens capsule, may develop.
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Guidelines for surgical intervention in Traumatic Hyphaema
To prevent optic atrophy
• Operate before IOP averages > 50mm Hg for 5 days
• Operate before IOP averages > 35mm Hg for 7 days
To prevent corneal blood staining
• Operate before IOP averages >25mm Hg for 6 days
• Operate if there is any indication of early blood staining To prevent peripheral anterior synechiae.
• Operate before a total hyphaema persists for 5 days
• Operate before a diffuse hyphaema involving most of the anterior chamber angle persists for 9 days.
In hyphaema patients with sickle cell haemoglobinopathies
• Operate if IOP averages ≥ 25mm Hg for 24 hours
• Operate if IOP has repeated transient elevations > 30mm Hg.
Traumatic Mydriasis and Miosis
Blunt trauma to the globe may result in traumatic mydriasis or, less commonly, miosis. Traumatic mydriasis is often associated with iris sphincter tears that can permanently alter the shape of the pupil. Miosis tends to be associated with anterior chamber inflammation. Pupillary reactivity may be sluggish in both situations.
Traumatic Iritis
Traumatic iritis is often associated with diminished vision and perilimbal conjunctival injection. The anterior chamber reaction can be surprisingly minimal but is usually present if carefully sought.
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Iridodialysis
Iridodialysis
Blunt trauma may cause traumatic separation of the iris root from the ciliary body. Frequently, anterior segment haemorrhage ensues, and the iridodialysis may not be recognized until hyphaema has cleared. A small iridodialysis requires no treatment. A large dialysis may cause polycoria and monocular diplopia, necessitating early surgical repair before the tissue becomes fibrotic.
Cyclodialysis
Traumatic cyclodialysis is characterized by a separation of the ciliary body from its attachment to the scleral spur, resulting in a cleft. Gonioscopically, this cleft appears at the junction of the scleral spur and the ciliary body band. Sclera may be visible through the disrupted tissue. A cyclodialysis cleft can cause increase uveoscleral outflow and aqueous hypo secretion, leading to chronic hypotony and macular edema.
Glaucoma Associated with blunt injury to the Angle
Glaucoma can occur either early or late following blunt injury and with or without angle recession. The great majority of these glaucoma‟s are associated with recession, with or withouthyphaema. These glaucomas can be classified as i. Acute glaucoma with Haemorrhage ii. Acute glaucoma without Haemorrhage iii. Chronic glaucoma with recession (Angle recession glaucoma) iv. Chronic glaucoma without recession.
32 i. Acute glaucoma with Haemorrhage
This glaucoma is due to trabecular meshwork obstruction by RBCs, platelets fibrin, and due to direct damage to the outflow channels. ii. Acute Glaucoma without Haemorrhage
Immediately following blunt injury, the intraocular pressure may often be slightly depressed. This may be due to decreased aqueous production by the traumatized and inflamed ciliary body or due to increased outflow either through the conventional pathway or the uveoscleral pathway. Occasionally, however, the pressure may be immediately elevated in association with the presence of inflammatory cells in the anterior chamber, which transiently obstruct the intertrabecular spaces. In addition, this elevation is usually associated with severe angle recession, although it is rare to have recession without haemorrhage. The increased resistance to outflow, in association with significant recession, is presumed to be due to associated trabecular meshwork disruption. Acute, severe, and often permanent glaucoma will rarely ensue without persistent inflammation and without visible angle recession. iii. Chronic Glaucoma with Angle Recession
Almost all patients who develop hyphaema following blunt injury have some degree of either recession or direct trabecular meshwork damage. If hyphema recovers without complication and the pressure normalizes, the patient should be examined gonioscopically approximately 6 weeks following the initial injury. If more than 1800 of the angle is recessed, there is upto a 10% chance of subsequent development of chronic glaucoma. Glaucoma that develops years later is believed to
33 be due to direct trabecular meshwork damage at the time of injury with subsequent scarring. iv. Chronic glaucoma without recession
Raised IOP can occur in the absence of angle recession due to post inflammatory pupil seclusion due to posterior synechiae and peripheral anterior synechiae.
Ghost cell glaucoma can also occur following 1 to 3 weeks of injury where fresh blood cells in vitreous convert to less pliable khaki colored ghost cells which block the trabecular meshwork and elevate the IOP.
Lens Injuries
Lens injury is a major complication of blunt ocular trauma. Contusion cataracts may occur as either early or late sequelae of the injury. Contusion cataracts are not invariably progressive, some remain stable and do not require surgery.
Pathophysiology
The pathogenesis of lens changes following blunt ocular trauma has been suggested by Wolter and by Weidenthal and SchepensThese authors have descried
“Coup” and “Contrecoup” injuries, along with equatorial expansion of the globe due to trauma, or the pathophysiological mechanisms responsible for ocular damage.
“Coup” refers to direct damage resulting in abrasion or laceration; “contrecoup” denotes injury occurring along a plane of trajectory, causing damage at a distal site as a result of shock waves.Contusion cataract formation, for instance, may result from contrecoup damage following a blow to the orbital area. Shock waves pass through
34 the eye, possibly rupturing the anterior or posterior lens capsule with subsequent lens opacification. The equatorial expansion theory suggests that blunt trauma applied to the globe in an anterior or posterior direction causes shortening of that meridian, with concomitant equatorial stretching. The equatorial expansion may cause rupture in the lens capsule or equator, resulting in lens opacification. Zonular disruption during a sudden increase in an equatorial meridian causes incomplete and asymmetric lens support, with resultant dislocation or subluxation.
Traumatic rosette shaped opacity
A rosette shaped opacity is also known as a stellate cataract, filiform cataract, or radiating sub-capsular cataract. They occur following blunt or perforating injuries.
These opacities were initially described by Dyer in 1986. There are two types of rosette shaped opacities.
Early rosette and Late rosette . i. Early rosette These opacities may be evident within a few hours after the injury, or may take weeks or a few months to develop. Following an injury to the lens capsule (anterior, posterior), fluid droplets accumulate between the radiating lens fibers in the subcapsular region appearing as feathery parallel rays, which run away from the suture lines, and appear to branch out from the axial region towards the equator, giving a rosette appearance. The feathery parallel rays around a central suture give the appearance of “Petal” and many such petals give the appearance of a
“rosette”.They have a uniform thickness. ii. Late rosette opacities These are noticed by the examining ophthalmologist some years following an injury. It may be that the patient has forgotten the injury as it may 35 have been trivial or when minimal amount of damage is produced in the subcapsular region, the damage becomes clinically apparent at a mean later date. These opacities lie deep in the cortex, or in the adult nucleus. The overlying lens fibres are clear.
Vitreous
Changes in the vitreous body after a concussion of any severity are invariable.
Vitreous Haemorrhage .
Vitreous haemorrhage may develop as a result of blunt trauma, causing minimal to severe visual loss. The bleeding occurs as a result of damage to ciliary body, retinal, or choroidal blood vessels. Vitreous haemorrhage from blunt trauma may be associated with retinal tear, and indirect ophthalmoscopy with scleral depression should be performed with great care in attempting to identify retinal abnormalities. Vitreous haemorrhage often is limited immediately after injury, with the initial fundus examination allowing best visualization of retinal details.
Subsequent diffusion of the haemorrhage or further bleeding may compromise later examinations. If the surgeon suspects an occult scleral rupture, scleral depression should be deferred. In general, patients with a non penetrating ocular injury and a vitreous haemorrhage should be observed for several months. In case of minimal diffuse haemorrhage, bed rest with the head of the bed elevated should be suggested to allow settling of the blood with gravity and permit indirect ophthalmoscopy.
However, if the blood does not settle, the patient should be followed every 4-6 weeks with ultrasonography repeated to confirm retinal attachment. If retinal detachment is seen or suspected on ultrasonography, pars planavitrectomy should be performed; otherwise, vitrectomy usually should be deferred for 3-6 months to permit spontaneous resorption of the haemorrhage. 36
Vitreous Base Avulsion
Trauma to the globe may disinsert the vitreous base from the peripheral retina and pars plana. Avulsion of the vitreous base results in minimal ocular symptoms, although the patient may complain of floaters associated with a partial vitreous detachment. Vitreous base avulsion alone does not have to be treated, but examination must be performed for associated traumatic ocular damage such as retinal dialysis, giant retinal tear, angle recession, or subluxated crystalline lens.
Retina
Several posterior pole retinopathies may result for blunt injury.
I. Commotio retinae
Commotio retinae (Berlin‟s oedema), first described by Berlin in 1873, is characterized by a transient, gray white opacification at the level of the deep sensory retina occurring after blunt trauma. This opacification may be confined to the macula or may involve extensive areas of the peripheral retina. The reasons for this retinal opacification are disputed, with some attributing it to extracellular oedema, however, experimental and histopathological studies have shown that disruption of the photoreceptor cells‟ outer segment and damage to the retinal pigment epithelium accounts for the retinal whitening.Vision can be markedly decreased with commotio retinae but vision most often improves as the swelling resolves over a 3-4 week period. However, the macula can develop an atrophic appearance with granular hyperpigmentation associated with decreased vision. In addition, the cystoid areas can coalesce to form a long cyst, which can lead to macular hole formation .
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Choroidal rupture
Choroidal ruptures, first described by von Graefe in 1854, are tears of the choroid, Bruch‟s membrane, and RPE resulting from non penetrating ocular trauma and are usually associated acutely with subretinal or Sub RPE – haemorrhage.
Direct choroidal rupture occurs anteriorly at the site of impact and are oriented parallel to the oraserrata; indirect choroidal ruptures occur posteriorly, away from the site of impact, and are generally crescent shaped with orientation concentric to the optic disc. The mechanism of choroidal rupture is thought to be primarily mechanical, although vascular damage may play a role. The sclera is somehow protected from mechanical compression and from sudden hyper expansion of the globe by its tensile strength, as the retina, is protected by its elasticity. However, Bruch‟s membrane lacks both strength and elasticity and thus is most likely to rupture. Patients with angioid streaks are particularly vulnerable to choroidal rupture because of increased fragility of Bruch‟s membrane. A major cause of poor vision resulting from choroidal rupture, other than extension of the rupture into the fovea is late development of subretinal neovascularization.
Traumatic Retinal tears and detachment
Retinal tears resulting from trauma are usually the result of damage to the retina at the vitreous base, although some tears may result from either direct blunt damage or indirect contrecoup injuries. Blunt trauma also can cause retinal breaks by transmission of the force to the vitreous, leading to acute severe vitreo-retinal traction. Rapid displacement of the vitreous can tear the retina in various ways, including retinal dialysis with or without avulsion of the vitreous base, operculated
38 retinal tear, macular hole; and horseshoe-shaped retinal tears at the posterior margin of the vitreous base, at the edge of a meridional fold, or at the equator.
Pathogenesis
The initiating event in the pathogenesis of retinal detachment resulting from blunt trauma is the forceful anteroposterior compression of the globe, which causes a lateral expansion of the equatorial area and tractional forces on the vitreous base.For a retinal detachment to occur after blunt trauma, a combination of two pathological changes must be present. First, retinal breaks may occur because of direct contusion or subsequent tissue necrosis as a result of vitreo-retinal traction following lateral equatorial expansion of the globe. Second, traumatic synersis of the vitreous gel overlying the retinal break may occur either immediately or months after blunt trauma. This liquefied vitreous may then dissect under the retinal break and cause a retinal detachment. Blunt trauma accounts for 70% to 86% of traumatic retinal detachments and characteristically occurs in young males.
Tasman reported 52 consecutive patients with ocular contusion examined within the first 3 weeks after injury and followed prospectively for 2 years. Retinal dialysis was found to be a common feature and was diagnosed within 3 weeks of injury in nine patients. Other Retinal Breaks Cooling described small, radial, slit like retinal tears located in the paravascular area between the posterior pole and the equator after contusion injuries. These tears occur at areas of strong perivascular vitreoretinal adhesion after forceful traumatic separation of the vitreous from the retina and may be associated with vitreous haemorrhage. Traumatic Macular Holes
Most traumatic macular holes result from closed – globe contusion injuries.
Possible mechanism for traumatic macular hole includes post contusion necrosis,
39 subfoveal haemorrhage, and acute vitreoretinal traction as a result of a contrecoup injury. Margherias and Schepens reported 10 (1.3%) macular breaks in 758 eyes with traumatic retinal detachments. A traumatic macular hole rarely leads to retinal detachment.
Optic nerve Avulsion
Optic nerve avulsion is an uncommon yet visually devastating event that usually occurs after non-penetrating ocular trauma, typically when an object intrudes between the globe and the orbital wall and displaces the eye. The avulsion injuries may occur as an isolated lesion. The optic nerve is forcibly disinserted from the retina, choroid and vitreous, and the lamina cribrosa is retracted from the scleral rim.
Both complete and partial avulsions have been described. Complete avulsion results in a blind eye with a fixed and dilated pupil. Sudden extreme rotation of the globe may be the major mechanism in some cases of optic nerve avulsion. Other postulated mechanisms include a sudden marked rise of intraocular pressure that forces the nerve out of the scleral canal or a sudden anterior displacement of the globe.There is no effective medical or surgical treatment for this condition
Sclera
Ruptures of the sclera:
Ruptures are due to a direct impact on the globe by a slowly moving blunt force, which is sufficiently powerful to burst it. There are two types of contusion ruptures based on the mechanism. They are
40
1. Direct ruptures
2. Indirect ruptures.
Direct scleral ruptures:
It is seen over the anterior part of the sclera and is more common when the sclera is thin due to an old inflammation, high myopia, staphyloma, buphthalmos.
Mechanism:
When the force hits the eye with sufficient intensity, the site of impact is suddenly indented and ruptures. This is of two types
Complete direct rupture: When all the layers of the sclera are ruptured.
Incomplete direct rupture: when only part of the scleral thickness is ruptured.
It is common for the inner layers of the sclera to rupture. It is clinically difficult to prove whether a scleral rupture is complete or incomplete.
Incomplete ruptures commonly occur in the region of the canal of Schlemm and usually follows a minor trauma at the limbus from light bodies e.g. a small piece of metal, pencil etc
Indirect ruptures
They occur following a severe blunt trauma to the globe. They are usually associated with grave intraocular damage and the complications are severe.
The rupture always occurs away from the site of impact.
They are of two types
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Complete indirect ruptures: They are relatively common. This is more common in old patients because of the loss of resilience of the sclera as age increases, or in a diseased sclera eg. staphyloma, buphthalmos, high myopia. In a diseased sclera, a less severe injury can produce a rupture.
Indirect incomplete ruptures: They are rare. The inner layers of the sclera undergo a rupture. According to the pathological anatomy, there are two types of ruptures:
Typical ruptures: They start internally in the extreme periphery of the anterior chamber, traverse the trabecular meshwork and the canal of Schlemm and run through the sclera, posteriorly and obliquely reaching the surface of the globe 3-4mm behind the cornea. Commonly, some amount of intraocular tissue is incarcerated in the rupture.
Atypical ruptures: They start internally as mentioned above and after traversing the canal of Schlemm, they run in an obliquely forward direction, to appear externally at the limbus, or on the cornea. They are usually 2-4mm in length. They have a good prognosis, partly because of their small size and partly because the prolapse of the intraocular structures is confined to the iris.
Clinical features of a ruptured globe:
There is pain, excessive lacrimation, loss of vision, shock.
1. Cardinal sign-softness and collapse of the globe.
2. Lids-swollen, bruised and often, it is difficult to open the eye.
42
3. Proptosis with orbital hemorrhage.
4. The conjunctiva may be torn or may be intact. Often, a massive sub
conjunctival haemorrhage obscures the scleral rupture.
5. Once the subconjunctival hemorrhage is absorbed, the scleral rupture is
visible.
There is a gape in the sclera, with eversion of its edges. The uveal tissue is seen to bulge into the gape as a black tissue. In a complete rupture if the conjunctiva is also torn, the contents of the globe are extruded outside. In a less severe trauma, the following features are seen:
1. The iris may be intact.
2. The lens may be dislocated.
If it gets incarcerated in the rupture, it may prevent extensive prolapse of the intraocular tissues. Very rarely, the lens may remain in its normal anatomical position.
Prognosis: The prognosis in general is poor.
1. The best prognosis is in small limbal ruptures in which the ciliary body is not
involved. The final vision is good.
2. Prognosis is also good in cases where not much damage has occurred to the
ocular structures.
43
3. The prognosis is very poor in cases with severe trauma. The vision is severely
impaired due to vitreous opacities and proliferation of fibrous tissue in the
posterior segment of the globe.
Sympathetic ophthalmia has been known to occur rarely.
Prognosis of Open-Globe Injuries
In any review of trauma patients, it becomes obvious that certain types of injuries carry a better prognosis than others. Many anatomical and pathological factors that carry either a good or poor prognosis have been studied in numerous studies in the past.10 Despite major advances in microsurgical techniques and an improved prognosis for traumatized eyes, the factors that cause poor vision have remained largely unchanged.12 Most of the studies of these factors were plagued by the lack of a common terminology to share eye injury information. The Birmingham
Eye Trauma Terminology (BETT)16,17 has now standardized the language used by ophthalmologists to describe a traumatized eye.
Terminology and Classification of Ocular Trauma
A standard language for ocular trauma, called the Birmingham Eye Trauma
Terminology, was suggested by Kuhn and associates16,17 in 1996 and adopted by the
International Society of Ocular Trauma in 1997.18 Its aim was to provide a clear definition for all injury types and to place each injury type within the framework of a comprehensive system. Figure 6 describes an overview of the internationally accepted classification of injuries to the globe.
44
Figure 6: Overview of the terminology and classification of globe injuries accepted by the International Society of Ocular Trauma.16,17
According to the BETT an „Open Globe Injury‟ refers to „a full thickness wound of the eye wall (cornea and/or sclera)‟. Although technically the eye-wall has three coats posterior to the limbus, for clinical and practical purposes violation of only the most external structure was taken into consideration. Any injury that is not a full thickness injury would have been considered as a „Closed Globe Injury‟, and these injuries were not included our study.
An open globe injury could be further classified as a laceration or a globe rupture. The term „rupture‟ refers to a full-thickness wound of the eye-wall caused by a blunt object. The term „laceration‟ refers to a full-thickness wound of the eye-wall caused by a sharp object. This does not include partial thickness wounds of the eye- wall, which would be considered a „closed globe injury‟. According to the BETT, a partial thickness laceration of the eye-wall is referred to as a „lamellar laceration‟.
45
An open laceration of the eye wall is classified further as a penetrating injury, perforating injury or an injury with a retained foreign object. A penetrating injury refers to an open globe injury with an entrance wound only. If more than one wound is present, each must have been caused by a different agent. On the other hand a perforating injury consists of entrance and exit wounds caused by the same agent. A globe injury with a retained foreign object is technically a penetrating injury, but grouped separately because of different clinical implications. Such injuries are grouped as „Intra-Ocular Foreign Body‟ (IOFB) injuries.
Some injuries remain difficult to classify. For instance, an intravitreal ball- bearing pellet is technically an IOFB injury. However, since this is a blunt object that requires a huge impact force to enter the eye, there is an element of rupture involved.
In such situations, the ophthalmologist is encouraged to describe the injury as
"mixed" (ie., rupture with an IOFB) or select the most serious type of the mechanisms involved.
The Ocular Trauma Classification Group (1997)18 proposed the now widely accepted method of classifying mechanical injuries to the globe with the aim of standardising the assessment of ocular trauma such that outcome measurement can be divided into comparable groups. The basis for classification was the anatomical and physiological factors that have been shown to be prognostic of visual outcome in ocular injuries.
The Ocular Trauma Classification Group drew inspiration from the „Trauma and Injury Severity Score‟ (TRISS) and „A Severity Characterisation of Trauma‟
(ASCOT) scores.18 The TRISS40 and ASCOT41 were developed for classifying injuries into prognostic categories for the purpose of assessment of outcomes of 46 trauma care provided by hospitals. The ocular adaptation of this was inspired by the classification of proliferative vitreoretinopathy and retinopathy of prematurity, both of which are based on outcome related anatomical and physiological factors.18
The ocular trauma classification assesses four specific variables: one anatomical, two physiological and one etiological. The variables were chosen for assessment such that a combination of these will adequately describe the nature and extent of injury. They can be assessed clinically on initial ophthalmic evaluation or during the initial surgery. If, for any reason, the intraocular structures are not fully assessed, this system needs the assistance of ancillary testing (such as computed tomography or echography) to classify the injury.
The four variables of the classification proposed by the Ocular Trauma
Classification Group were:
1. Type of injury
2. Grade of injury
3. Presence of a relative afferent pupillary defect
4. Zone of injury
47
Open globe injury classification Closed globe injury classification
Type Type
·Rupture ·Contusion
·Penetrating ·Lamellar laceration
·Intraocular foreign body ·Superficial foreign body
·Perforating ·Mixed
·Mixed
Grade Grade
Visual acuity Visual acuity
·> 20/40 ·> 20/40
·20/50-20/100 ·20/50-20/100
·19/100-5/200 ·19/100-5/200
·4/200 to light perception ·4/200 to light perception
·No light perception ·No light perception
Table 3: International Society for Ocular Trauma classification of an Open Globe
Injury and closed globe injury.
Zone of injury 48
Pieramici et al elaborated the zones of injury for open and closed globe injuries.
Zone of injuries for open globe injuries
The zone of injury is defined by the location of the most posterior full-thickness aspect of the globe in open injuries.
Figure 7: Zone of injury for open globe injuries
Zone I (yellow): Opening of globe is isolated to cornea or corneoscleral limbus.
Zone II (red): Injuries involving anterior 5 mm of sclera, (in most eyes, this does not extend behind the pars plana).
Zone III (blue): Injuries extending full thickness into scelra>5mm posterior to corneoscleral limbus.
49
Zone of injuries for closed globe injuries
Zones in closed globe injuries are related to anteroposterior anatomic location of injury. As these do not involve full thickness wounds, injuries are zoned according to tissues injured.
Figure 8: Zone of injury for closed globe injuries
Zone I (yellow): Superficial injuries limited to bulbar conjunctive, sclera, or cornea.
Zone II (red): Structures involving anterior segment up to and includes lens apparatus and the lens, zonules and pars plicata.
Zone III (blue): Posterior injuries involving pars plana, choroid, retina, vitreous or optic nerve.
The type of injury 50
Ideally refers to the circumstance of injury as reported by the patient or witnesses to the incident. In situations where the patient in unconscious and there are no witnesses to the injury, the typing will be based on the overall findings from examination. If the presence or absence of an intraocular foreign body cannot be confirmed by clinical examination, ancillary testing is warranted.
The grade of injury
Is based on the visual acuity of the injured eye at initial examination, and should be attempted on patients who are able to cooperate. In intoxicated or comatose patients or patients who are too young, classification of the injury based on this variable is impossible. The testing is done at a distance (using Snellen acuity chart) or near-by (using a Rosenbaum card). All testing should be done with the patient‟s corrective lenses, with and without pinhole. If the acuity improves with the pinhole, that is recorded as the visual acuity at initial examination. Light perception is tested using a bright light source, such as an indirect ophthalmoscope set at the highest intensity.
The presence of a relative afferent pupillary defect is assessed with the swinging flashlight test. If the pupil of the injured eye is mechanically or pharmacologically not reactive or the pupil is not visible, the consensual response of the fellow eye should be assessed.
Important Prognosticating Factors in Open Globe Injuries
Ophthalmologists cannot rely on most of the existing scientific data to predict the visual outcome of an injured eye. They are most often confused by the data, in part due to ambiguous terminology (before the advent of BETT) and in part due to the 51 conflicting results of the studies. Kuhn F et al. (2002) analysing over a hundred factors in 2500 injured eyes for the development of the Ocular Trauma Score11. Of the variables analysed, only a few were found to be reliable in predicting the long- term visual acuity as well as easy to determine during initial clinical examination or surgery. These factors were found to be initial visual acuity, type of injury (with more significance to rupture and perforating injuries), the presence of an afferent pupillary defect, the presence of a retinal detachment and the presence of endophthalmitis.
Recent studies in South India by Gothwal et al (1999)33 have echoed the importance of initial visual acuity, endophthalmitis and retinal detachment as factors associated with visual impairment (visual acuity less than 6/18). The factors which are proven predictors of final visual acuity will be reviewed first, as these are the key factors being studied. The zone of injury has been included into the discussion of the key factors as it constitutes a part of the classification of open globe injuries. A discussion on other factors that have been studied as predictors of visual acuity in open globe injuries will follow.
Key Factors Affecting the Visual Outcome
In this part of the scientific literature review, the following factors will be discussed:
1. Visual Acuity at Presentation (Grade of Injury)
2. Afferent Pupillary Defect (RAPD: Positive or Negative)
3. Type of Injury
4. Zone of Injury
52
5. Presence of Retinal Detachment
6. Presence of Endophthalmitis
1. Visual Acuity at Presentation:
Visual acuity at the time of presentation appears to be the single most important factor in predicting the final visual acuity in open globe injuries. In a review of 453 patients, de Juan et al (1983) found that 97% with an initial visual acuity of 5/200 or better regained a final visual acuity of 5/200 or better. 30 When the initial visual acuity was worse than 5/200, there was only a 36% chance of regaining a vision of better than 5/200. A subsequent multivariate analysis of the data by
Sternberg et al (1984) showed that the initial visual acuity was found to be the most important factor in determining the final visual acuity. 15 Eyes with an initial acuity of
5/200 or better were 28 times more likely to have a final visual acuity at that level than eyes with initial acuity worse than 5/200. Barr (1983), in his analysis of corneo- scleral lacerations, found initial visual acuity and visual acuity at discharge to be good predictors of final vision. 42 In his study,87% of those with an initial acuity of better than 6/30 had a vision of 6/12 or better after six months and 54% of those with an initial acuity of worse than hand movements did not improve to better. Hutton and
Fuller (1984) studied the post-operative visual acuity in 191 corneoscleral lacerations and found that a vision of 5/200 tended to fare better and those with less than 5/200 tended to have a less predictable outcome. 43 Furthermore, they suggested that prediction of the visual outcome in those injuries that present with poor vision need to be based on other factors.
53
In the ISOT classification of an open globe injury the visual acuity of the injured eye at initial examination is indicated by five grades of injury. 18 The prognostic significance of the open globe injury classification was described in a recent study by Pieramici et al (2002). 13 In the first study of this kind, it was found that a vision of better than 20/50 was achieved in 95% patients with grade 1 and 75% with grade 2 injuries. This was achieved in only 70% of grade 3, and 34% of grade 4 injuries. None of those with grade 5 injuries could achieve the same results. The eyes with the most unpredictable outcome were those with a grade 4 injury. In that group a vision of better than 20/40 was regained in 34%, between 20/50 to 5/200 in 20%, between 5/200 to light perception in 25% and no light perception in 2%. The remaining 19% of the eyes of group 4 were enucleated. Additionally, the odds of attaining vision worse than 20/40 were determined for the different groups taking grade 1 injuries to be the reference. It was found that the odds of the final vision being worse than 20/40 was 5.18 for grade 2 injuries, 8.14 for grade 3 injuries and
48.56 for grade 4 injuries.
2. Afferent Pupillary Defect:
The assessment of a relative afferent pupillary defect (RAPD) in the injured eye, as with the measurement of acuity, is a functional test. These variables are physiological parameters that measure function and are not directly descriptive of the injury. It has been previously noted that the characteristics of grade (visual acuity) and pupil (presence of RAPD) were the most accurate predictors of visual outcome.13,14,15
Pupillary examination has been called the “poor man‟s” visual evoked potential. 12 54
In the study by Hutton and Fuller (1984) they found that Flash Visual-Evoked
Potential (VEP) correlated better than both initial visual acuity and bright flash electroretinography as an indicator of the final visual acuity. They noted that the response to Flash VEP was reduced when the macula or optic nerve were involved in the damage. The test does not require contact with the eye and can be done in the presence of an opaque media. This makes it similar to pupillary examination, which can also determine damage to the macula and optic nerve when done correctly.
In the study by de Juan et al (1983) the presence of an afferent pupillary defect was associated with a poor visual outcome30. Of the 13 eyes with an afferent pupillary defect, only 2 of them (14%) regained vision of 5/200 or better, as opposed to 59 of 84 eyes (74%) without an afferent pupillary defect. Unfortunately, in the retrospective analysis of the 453 patients studied, afferent pupillary response was documented in only 97 patients (21%).
In the ISOT classification of an open globe injury “pupil positive” refers to the presence of a relative afferent pupillary defect in the injured eye and “pupil negative” refers to a normal response. 18 The prognostic significance of the pupillary response being “pupil positive” was studied in a recent study by Pieramici et al
(2002). 13 It was found that after a three month period a vision of better than 20/50 was achieved in 62% of “pupil negative” eyes while only 11% of those who were found to be “pupil positive”could attain a similar visual results. It was observed that
41% of the “pupil positive” eyes required enucleation while only 8% of the “pupil negative” eyes required enucleation. The study also noted that the pupillary response was not recorded in 42 of the 290 eyes studied (14%). The reason for not being able to studying an afferent pupillary response could the result of bilateral efferent
55 pupillary defects or the patient being monocular. However the authors opined that it was more likely that no attempt was made to measure or record the pupillary response.
3. Type of Injury
The type of injury is defined by the mechanism of injury. Hutton and Fuller
(1984) retrospectively analysed 191 eyes treated by vitrectomy and found that the type of injury sustained was a statistically significant predictor of final visual acuity.
43In a study of the types of injuries and visual results in perforating ocular injuries de
Juan et al (1983) concluded that the prognosis of an injury is strongly influenced by the nature of injury. 30 Both those studies classified the injuries into three categories
(lacerations, foreign body injuries and blunt injuries) according to the etiology of injury. According to the ISOT classification of mechanical globe injuries 17,18, open globe injuries can be
Classified into the following five types:
A. Globe Rupture
B. Penetrating Injury
C. Intraocular foreign body
D. Perforating Injury
E. Mixed
A. Globe Rupture:
56
It has been demonstrated previously that blunt forces result in ocular rupture and carry a poor prognosis. In a study of corneoscleral lacerations Barr (1983) found that 35% of injured eyes which were a result of a blunt injury were enucleated as opposed to 13% of those which were due to sharp objects. 42 He also found that 52% of the blunt injuries resulted in a vision that was hand movements or worse, when compared to only 25% of those due to a sharp injury. Further analysis demonstrated that the difference was statistically insignificant. Esmaeli et al (1995) found that enucleation following a blunt injury was responsible for 65% of the enucleations that were required after a penetrating eye trauma while only 13% of enucleations were the result of a sharp injury and 41% were the result of a missile (foreign body) injury. 44
When compared to sharp injuries the difference was found to be statistically significant, whereas when compared to missile (foreign body) injuries the difference was not significant. In a study of the types of penetrating (open globe) ocular injuries de Juan et al (1983) showed that injuries from a blunt force had a worse prognosis which was statistically significant when compared to both sharp injuries and missile
(foreign body) injuries. 30
In studies that were done after in accordance with the terminology proposed by the Birmingham Eye Trauma Terminology, Type A injuries referred to a „Globe
Rupture‟ which is an open globe injury sustained after a blunt injury. Kuhn et al
(2002) listed out the importance of various factors for the prognosis of open globe injuries and found that a globe rupture carried a worse prognosis when compared to a perforating injury. 11Sobaci et al (2000) studied 228 eyes injured in military confrontation and found that 100% of all Type A injuries had an unfavourable outcome (defined as a visual acuity of less than counting fingers at one meter,
57 including evisceration or enucleation). 45 In a study comparing the types of injuries,
Pieramici et al (2003) found that in eyes with a Type A injury 27% ended up with a visual acuity of better than 20/40 while 29% required enucleation. The odds of having a visual outcome worse than 20/40 were calculated to be 4.09 times more with a Type
A injury than that with a Type B (Penetrating) injury.13 This was attributed to the fact that a more diffuse injury causes a force to be transmitted throughout the globe, and significant ocular wall deformation can result in injury which is away from the site of impact.
B. Penetrating Injury:
In general, injuries that result from a sharp force carry a much better prognosis. This has been attributed to the fact that sharp forces that result in a more localized transmission of force. Barr (1983), in an analysis of 106 corneoscleral lacerations, found that out of the 75 patient with a sharp injury 47% had a final visual acuity of 6/12 or better, 25% achieved a vision of hand movements or worse and only
13% were enucleated. 42Esmaeli et al (1995) found that 80% of the injured eyes that resulted in a good visual acuity (better than 20/200) were due to sharp injuries and enucleation following a sharp injury was responsible for only 13% of the enucleations that were required.44In a study of the types of penetrating (open globe) ocular injuries de Juan et al (1983) showed that injuries that the difference in outcome between an injury due to a sharp force and that due to a missile (foreign body) was not statistically significant. 30
Prior to the advent of the terminology proposed by the Birmingham Eye
Trauma Terminology the term „sharp injury‟ was used in many studies. The term
„sharp injury‟ could mean a penetrating, perforating injury or even a lamellar 58 laceration (now classified as a closed globe injury). In the ISOT classification of open globe injuries, a „Type B‟ injury referred to a „Penetrating Injury‟ which is an open globe injury sustained by a sharp force, excluding perforating (Type D) injuries and injuries with a foreign body (Type C). Sobaci et al (2000) studied 228 eyes injured in military confrontation and found that 73% of all Type B injuries had a favourable outcome (defined as a visual acuity of better than counting fingers at one meter, which usually permits unaided ambulation). 45 None of the Type A injuries could achieve the same, while 8% of Type E, 23% of Type D and 45% of Type C could achieve the same. Pieramici et al (2003) found that after a 3 month period in eyes with a Type B injury, 60% had a visual acuity of better than 20/40, 18% were between 20/50 to 5/200, 7% were between 5/200 to a vision of light perception and
1% had no perception of light. In the study, only 14% of Type B injuries required enucleation.13
C. Intraocular Foreign Bodies:
Several investigators have studied the importance of the presence of an intraocular foreign body (IOFB) with respect to prognosis. A variety of surgical advances have lead to an improved capability for managing most foreign bodies so that eyes with intraocular foreign bodies seem to have a good prognosis. 12 In a study of posterior segment injuries requiring vitrectomy, Brinton et al (1982) found that eyes with intraocular foreign bodies had a better prognosis than the others. 31 63% of the injuries studied with intraocular foreign bodies had a visual acuity of 6/30 or better when compared to only 46% in the other group. A delayed surgical removal of the foreign body resulted in worse prognosis. In a retrospective review of 105 eyes with retained foreign bodies, Williams et al (1988) reported that 60% of them
59 achieved a final visual acuity of 20/40 or better while 20% achieved between 20/50 to
5/200 and 15% were worse than 5/200. 46Esmaeli et al (1995) found that more eyes with an IOFB had a final visual acuity of better than 20/60. 44 In the retrospective case study of 75 patients by Greven et al (2000), 71% achieved a final visual acuity of better than 20/40 and 85% had ambulatory vision (better than 5/200). 47 Better prognosis in eyes with a foreign body has been attributed to the fact that most eyes with foreign bodies have anterior entry sites, small lacerations and a relatively good initial acuity12
In a case series of 105 eyes analysed by Williams et al (1988), 80% of the cases had posterior segment foreign bodies and 23% of the cases had foreign bodies in the anterior segment. (Some eyes contained multiple foreign bodies in different locations.) Of the posterior segment foreign bodies 61% of the foreign bodies were found to be located in the vitreous cavity, 14% were intraretinal and 5% were subretinal. 15% of the foreign bodies in the anterior segment were found in the anterior chamber. In the study by Greven et al (2000), 88% of the foreign bodies found were in the posterior segment (36% in the vitreous cavity) and 12% were found in the anterior segment (10% in the anterior chamber). 46
The nature of the foreign body was found to be related to the prognosis of the injury. In a study of intraocular foreign bodies, Greven et al (2000) found that foreign body injuries as a result of hammering metal on metal were statistically associated with a better prognosis. 47 In the study conducted by de Juan et al (1983) 65% of the eyes with a foreign body had as opposed to 58% without. 30 The prognosis was worse when the foreign body was a BB gun pellet, and excluding those injuries 75% of the eyes had ambulatory vision. Hutton and Fuller (1984) and Sternberg et al (1984)
60 found that eyes injured with BB gun pellets fared worse than those with other foreign bodies. 15,43
Magnetic foreign bodies tended to do better when compared to non-magnetic ones.12 Shock and Adams (1985) found that use of a magnet to remove the foreign body resulted in a better prognosis when compared to those that were removed manually. 48 They noticed that iatrogenic injury was less when a foreign body magnet was used.
Of 105 eyes with retained intraocular foreign bodies analysed by Williams et al (1988), 13% of cases were associated with an endophthalmitis. 46 Bacillus related endophthalmitis had the worst prognosis. In a study of ocular injuries with foreign bodies Jonas et al (2000) found that 5.4% of the injuries were associated with endophthalmitis. 49 The nature of the foreign body was an important factor in determining the chance of occurrence of endophthalmitis. Of the 4 injuries with wooden foreign bodies, 2 (50%) developed endophthalmitis and of the 123 injuries with metallic foreign bodies, 5 (4.1%) developed endophthalmitis. The difference was found to be statistically significant. They found that the occurrence of post traumatic endophthalmitis was more when the foreign body was removed 24 hours after the injury.
In the ISOT classification of open globe injuries, a „Type C‟ injury referred to an injury with an intraocular foreign body. Two-hundred and twenty eight eyes injured in military confrontation were studied by Sobaci et al (2000). 45 One-hundred and fifty four (67.5%) of these were of Type C. They found that 55% of all Type C injuries had an unfavourable outcome (defined as a visual acuity of less than counting fingers at one meter, including evisceration or enucleation). In contrast, Pieramici et 61 al (2003) found that in eyes with a Type C injury, 53% ended up with a visual acuity of better than 20/40 while 7% required enucleation.13 The odds of having a visual outcome worse than 20/40 was only 1.31 times more with a Type C injury than that with a Type B (Penetrating) injury. The difference was analysed and found to be statistically insignificant. The difference was attributed to the injuries caused by a BB gun or pellet injuries. They explained that BB gun pellets have a significant blunt force, which result in a diffuse destruction of the globe.
D. Perforating Injuries
Perforating injuries of the globe have been recognised as having a different prognosis and approach for management when compared to other open globe injuries.
18It was for this reason that Kuhn et al (1996) included this as a different type of injury while classifying open globe injuries. 16 Such injuries are now classified as
„Type D‟ in the ISOT classification of open globe injuries. In a perforating (through- and- through) injury there would have to be two full thickness defects in the eye wall
(entry wound and exit wound), both caused by the same object or foreign body. By this definition the object must not be within the globe at the time of examination
(excluding all injuries with an intraocular foreign body). Previously, authors have referred to such injuries as “double-perforating” or “double-penetrating” injuries, which is anatomically incorrect. 50
In a study of 106 eyes with posterior segment trauma, Brinton et al (1982), 16 eyes with perforating injuries were studied. Of these, 63% of the eyes achieved functional success. 31 In a study of 51 eyes with perforating injuries treated by vitrectomy, Martin et al (1991) found that the final visual acuity is most often worse than 5/200. 50 The authors noted that the initial visual acuity was also poor in these 62 patients, being limited to hand movements or light perception in 89% of the cases.
The final visual acuity correlated best with the post-operative status of the macula.
They reported a functional success rate of 63%. They attributed the improved prognosis to vitrectomy, stating that vitreous surgery helps salvage and restore useful vision in these eyes. They also suggested that vitrectomy be delayed to seven days after a perforating injury as a posterior leakage of fluid through the exit site and a lack of separation of vitreous from the retina hampered early surgery.
In a study of deadly-weapon related open-globe injuries by Sobaci et al
(2000), 77% of the Type D injuries resulted in an unfavourable outcome. 45 In a study of the prognostic significance of the classification of open globe injuries by Pieramici et al (2003), it was determined that a perforating injury (Type D) had the least probability of achieving a good visual outcome. 13 Type D injuries were 12.00 times more likely to have a visual outcome of worse than 20/30 when compared to a penetrating (Type B) injury. Fifty-six percent of the Type D injuries achieved a final visual acuity between 5/200 to light perception, 22% achieved between 20/50 to
5/200 and 11% achieved a vision better 20/50. Eleven percent of the eyes required primary enucleation.
E. Mixed injuries
Mixed injuries are those that involve multiple mechanisms. Such injuries are classified as „Type E‟ in the ISOT classification of open globe injuries. Sobaci et al
(2000) studied 183 patients with deadly-weapon related open globe injuries. 45Only
13 eyes were classified as having an injury with mixed etiology, 12 of them having an unfavourable outcome.
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4. Zone of Injury
As mentioned before, the zone of injury is defined as the most posterior part of the globe involved in the open globe injury. 16,17 Zone I refers to injuries that are isolated to the cornea (including the limbus). Zone II injuries refers to injuries between the corneosclerallimbus to a point 5mm posterior to the sclera and Zone III refers to any injury posterior to the anterior 5mm of the sclera. A study by Mukherjee et al found that purely corneal lacerations dominated their series (62.21%). 51
Posterior injuries generally carry a graver prognosis.12 This was attributed to the fact that injuries involving sclera are more likely to violate the integrity of the vitreous, damage the retina and ciliary body. The possibility of causing a retinal detachment or loss of ciliary function gives posterior injuries a graver prognosis. In a study of the surgical results in posterior segment ocular injuries, Brinton et al (1982) found that out of the 106 eyes studied only 55 eyes (52%) achieved functional success
(defined as a final visual acuity of 6/30 [20/100] or better or as a postoperative improvement in visual acuity from light perception or worse to 6/240 [5/200] or better). 31 In a study by de Juan et al, (1983) they describe the importance of the location of an injury to the visual outcome.30 They found that found that 83% of the injuries limited to the cornea could regain a vision of better than 5/200, while 48% of the corneoscleral injuries and 40% of the scleral injuries could achieve the same.
With injuries involving the sclera, they found that 60% those limited anterior to the rectus muscle insertion regained ambulatory vision as opposed to only 28% those extending behind it.
In a recent study, Pieramici et al (2003) found that the zone of injury was a statistically significant predicting variable for visual outcome.13 A three month 64 follow-up visual acuity of 20/40 was achieved in 62% of those with Zone I injuries while 39% of Zone II and 25% of Zone III injuries could achieve the same. They concluded that once the retina or optic nerve gets involved the damage is invariably irreversible hence carrying a worse prognosis.
5. Retinal Detachment
Development of a retinal detachment is a poor prognostic sign. In a study of
B-mode ultrasound examination in ocular trauma by Rubsamen et al (1994), 65% of the eyes examined demonstrated a retinal detachment at presentation. 52In a study of deadly- weapon related open globe injuries, Sobaci et al (2000) found that 74% of the open- globe injuries with retinal detachment had unfavourable outcomes. 45Greven et al (2000) found that retinal detachment was one of the factors associated with a poor prognosis in eyes with a retained intraocular foreign body, but this was not found to be statistically significant when adjusted for presenting visual acuity. 47Pieramici et al
(1997) recognized that retinal detachments often occur weeks to months after trauma, and is very rarely due to the injury itself. 18
In a study of traumatic retinal detachments Matthews et al (1998) found that the number of quadrants involved was one of the statistically significant predictive factors of the final visual outcome and ocular survival.53 Eighty-eight percent of the eyes with a four quadrant retinal detachment had a poor visual outcome and 55% were enucleated. The other factors were which predicted the outcome in these patients were visual acuity at presentation, location of injury and mechanism of injury. It was also found that post- traumatic retinal detachments were complicated by proliferative vitreoretinopathy, persistent retinal detachment, macular scar and optic atrophy, and these resulted in significant post-operative morbidity. 65
6. Endophthalmitis
Endophthalmitis is an uncommon condition but an import one due to its association with a poor visual function. Sobaci et al (2000) found endophthalmitis in
8.3% of 228 eyes with open globe injuries. 45 In a study of post-traumatic endophthalmitis by Thompson et al (1995), they found that endophthalmitis occurred in 13 (6.3%) of the 205 eyes with a sharp injury54 None of the blunt injuries were associated with an endophthalmitis. They also found that the presence of lens disruption was the most significant risk factor for endophthalmitis. It was found that
54% of patients with post-traumatic endophthalmitis achieved a vision of 20/400 or better, with 27% achieving better than 20/50. The best visual outcome was associated with endophthalmitis caused by coagulase-negative Staphylococci, while Bacillus cereus was the organism associated with the worst outcome.
As mentioned before, in eyes with retained intraocular foreign bodies, 13% of cases analysed by Williams et al (1988) were associated with an endophthalmitis, as compared to 5.4% by Jonas et al (2000). 46,49 Bacillus related endophthalmitis carried the worst prognosis. 46 Wooden foreign bodies were associated with endophthalmitis significantly more than metallic foreign bodies. 49 The occurrence of post traumatic endophthalmitis was more when the foreign body was removed later than 24 hours after the injury.
The Ocular Trauma Score
After statistical analysis of more than 2500 injuries and evaluating more than
100 variables in them, Kuhn et al (2002) were successful in listing six key factors which can predict the outcome of an injured eye. 11 The factors were brought together
66 to form the Ocular Trauma Score (OTS), which aims to provide a single probability estimate of the vision that might be achieved six months after the trauma. The OTS is designed to be used as an aid in the counseling and treatment of eye injury patients, and is able to direct attention toward resource needs and rehabilitation during the treatment process.
The key factors involved in determining the Ocular Trauma Score are visual acuity at presentation, the presence or absence of a globe rupture, the presence or absence of endophthalmitis, the presence or absence of a perforating injury, the presence or absence of retinal detachment and the presence or absence of a relative afferent pupillary defect. A certain raw number has been assigned to each of the factors. The number depends on the influence of each factor on the final visual acuity.The score can be calculated using the following tables (Table 4 and Table 5):
Variable Raw points
A) Initial vision
No light perception 60
Light perception/ Hand motion 70
1/200 – 19/200 80
20/200-20/50 90
67
> 20/40 100
B) Rupture -23
C) Endophthalmitis -17
D) Perforating injury -14
E) Retinal detachment -11
F) Afferent pupillary defect -10
Table 4: Variables with raw points at initial examination
Raw score sum = sum of raw points
To calculate the ocular trauma score:
1. Determine the patient‟s initial visual acuity after the injury and their tissue diagnoses.
2. Assign a raw point value for initial visual acuity from row A from Table 2. Then subtract the appropriate raw points for each diagnosis from rows B to F. Example: a patient with an initial visual acuity of 1/200, scleral rupture, and retinal detachment would receive a raw OTS score of 80-23- 11= 46.)
3. Higher OTS scores tend to indicate a better prognosis.
68
4. To provide an estimate of the patient‟s probability of attaining a specific visual acuity range at a six-month follow-up, locate the row in Table 3 corresponding to the patient‟s OTS.
Sum of OTS No light Light 1/200- 20/200- >
raw perception perception/hand 19/200 20/50 20/40 points motion
0-44 1 74% 15% 7% 3% 1%
45-65 2 27% 26% 18% 15% 15%
66-80 3 2% 1% 15% 31% 41%
81-91 4 1% 2% 3% 22% 73%
92-100 5 0% 1% 1% 5% 94%
Table 5: The OTS score and the patients probability of attaining a specific visual
acuity can be determined from the raw score. (Obtained from Table 4)
Other Factors Affecting Visual Outcome:
69
Other anatomic and physiological factors have also been identified as prognostic factors for open globe injuries. Kuhn et al (2002) listed several variables of prognostic importance that have been published in various studies. 10 The factors listed were age, sex, laterality of eye injured, cause of injury, type of injury, facial fractures, initial visual acuity, wound location, extent of wound, hyphaema, IOFB, presence or absence of lens, lens injury, retinal detachment, vitreous haemorrhage tissue prolapse, VEP and ERG. They also mentioned that the studies sometimes contradicted each other, while others had different cut off values for the same factor.
Other than the six key factors previously discussed, Pieramici et al (1997) have identified the ones of prognostic significance to be size of the wound, presence or absence of vitreous haemorrhage and lenticular involvement. 18
Length of Laceration
Hutton and Fuller (1984) showed that lacerations greater than 12mm carried a graver prognosis. 43 De Juan et al (1983) showed used 10mm as the definition of a large laceration and found that lacerations longer than this tended to be predictors of a poor visual outcome. 30 However, in both series, they concluded that factors describing the functional status of the eye were more important than those related to anatomic factors such as laceration length. In a study of the surgical results in posterior segment ocular injuries, Brinton et al (1982) analysed a combination of location and length and found that 25% eyes with scleral lacerations greater than 5 mm carried a graver prognosis when compared to the others. 31Pieramici et al (1997) considered the location of the wound to be more important than wound length. 18
They also thought that wound length reporting would be redundant.
Vitreous Haemorrhage 70
In experimental models using the rhesus monkey, Cleary and Ryan (1979) found that retinal detachment was more likely to occur in the presence of a vitreous haemorrhage, and (in 1981) went on to demonstrate that vitrectomy decreased the chances of developing retinal detachment. 55,56 Others have also recognised the clinical implication of vitreous haemorrhage, and it has been identified as a significant prognostic factor in these injuries. 57, 30, 42 Brinton et al (1982) demonstrated that eyes with moderate to severe vitreous haemorrhage had a 48% functional success rate as opposed to 67% in eyes with mild or no haemorrhage.
31Rubsamen et al (1994) noted that the diagnosis of vitreous haemorrhage in a penetrating ocular injury often requires ancillary testing with B-mode ultrasonography. 52Pieramici (1997) recognised that this may be inappropriate or not available during the initial assessment of globe injuries. 18
Hyphaema
Hyphaema was found to signify a poor prognosis in the analysis of corneoscleral lacerations by Barr et al (1983). 42 However, other studies have shown the association tobe less important. 58,59Chiquet et al (1998) studied 40 injuries with intraocular foreign bodies and found that the presence of hyphaema was not associated with either a good or bad visual outcome.58Khatry et al (2004) found that although hyphaema was associated with a poor vision at presentation, its association with poor vision at follow- up was less significant.
Lenticular Involvement
The involvement of the crystalline lens has been identified as a poor prognostic factor in numerous studies. 30,42,54,57 However, Pieramici et al (1997)
71 considered this factor to be of limited importance because of the difficulty in confirming the extent and nature of lenticular involvement in open globe injuries.18
Risk factors for ocular trauma
Age: The incidence of ocular trauma shows a bimodal curve with peaks at two extremes of life, children and older persons.
Gender: Males show higher incidence of ocular trauma compared to females as compared females.
Socioeconomic status: More eye injuries have been found to be associated with low socioeconomic status.
Lifestyle and personal behavior: In urbanized and industrialized countries, high risk of ocular injuries are present, along with lifestyle habits of sports practice, motor vehicle crashes, etc.
Domestic eye injury: About 7-60% injuries may be due to domestic causes, like domestic trauma or children activities.
Warfare: There is an increase in incidence of ocular injuries about 20-50 times compared to civilian situations.
Assault related: These represent 1-53% of reported ocular injuries.
Special Situations
1. Occupational Injuries
72
Occupational settings provide an important source of severe ocular injuries. 60
The incidence of occupational eye injuries vary from region to region. The United
States Eye Injury Registry found that 21% of all ocular injuries were work related. 61
A population-based survey in New England (USA) by Glynn et al (1988) showed that
59% of the eye injuries occurred at work.62A retrospective study conducted in Los
Angeles, USA by Liggett et al (1990) found that only 8% of the eye injuries in their series occurred at the work place. 24Most western studies seem to show a decrease in the incidence of occupational eye injuries over the past few years. 61 Indian studies have also shown a variation in the incidence of occupational injuries. Shukla and
Verma (1979) found that occupational injuries accounted for 29% of all ocular injuries studied in Raipur. Mukherjee et al (1984) found that 52% of perforating eye injuries in Goa were occupational injuries. 51 A large proportion of these injuries were related to agriculture orforestry (24%).
A retrospective record review of 128 open-globe injuries by Vasu et al (2001) in our institute showed that 33% of the injuries were occupationally related. 63They found that 76.7% of those studied were not wearing the recommended protective eyewear, and that 13.9% were under the influence of alcohol. The visual outcome was also found to be poor in this group, with 93% of the moderate and severe injuries resulting in a vision of worse than 6/60.
Adequate eye protection in the workplace can prevent many serious eye injuries and more attention needs to be directed toward the development of comfortable protective eyewear for use in a wide variety of occupational settings.60
2. Paediatric Open Globe Injury
73
In India, ocular injuries have been identified as the major cause of acquired monocular blindness in children. 64 Children are more vulnerable to ocular trauma because of the ignorance, immature motor skills and natural curiosity.
In a retrospective cross-sectional survey conducted by Cascairo et al (1994), they found that 54% of the perforating injuries resulting in a final visual outcome of
20/200 or worse. 65 Rudd et al (1994) retrospectively reviewed 46 children with a ruptured globe and found that 36% of the patients in their series achieved a final visual acuity of 20/400 or worse.66Vasnaik et al (2002) retrospectively reviewed the effect of mechanical eye injuries on children and found that 24.5% of the patients had a final visual acuity of 6/60 or worse. 64 Of the broom stick injuries studied by
Sharma et al (1994), they found that 29% of the children studied attained a final visual acuity of 6/36 or worse. 67
In terms of etiology, Rudd et al (1994) in their retrospective review found that that 59% of the perforating injuries in children were related to recreational activities.
66 Broomstick bow and arrow injuries in children were studied by Sharma et al
(1994).67 These injuries are unique to India, and were very common during the screening of the Mahabharata and Ramayana television serials. Most injuries reviewed by Cascairo et al(1994) were found to be preventable by adult supervision. 65
Open Globe Injuries-
Primary Repair of Corneoscleral Injuries
Ophthalmic Evaluation a complete and thorough ocular examination, keeping in mind the clues obtained from the history is the next vital cog in the trauma 74 management wheel. This should include flash light examination; Slit lamp examination and fundus examination whenever possible. Poor presenting visual acuity and relative afferent pupillary defect are the most significant prognostic factors that can be detected on presentation. Signs such as diffuse chemosis; massive subconjunctival haemorrhage; asymmetric deepening of anterior chamber; Low intraocular pressure; “uveal show” under the conjunctiva; hemorrhagic choroid detachment etc especially in combination should make one think of and actively search for a scleral rupture which may be trying to escape detection owing to the intact conjunctiva or chemosis above it or due to its posterior location or location beneath the muscle insertion. If the initial examination still fails to exclude a rupture or a hidden full thickness scleral wound and even an iota of suspicion remains, then don‟t hesitate to do an exploration in the OT after doing the necessary peritomy. In case of children this of course means general anesthesia.
Imaging in Ocular Trauma CT Scan is the imaging modality of choice in the acute setting of an Ophthalmic trauma were we are suspecting an Open globe injury.
This can uncover or give corroborative evidence in cases of Occult globe rupture; detect IOFBs; give an idea of the orbital pathologies like retro bulbar hemorrhage;
Orbital wall fractures . The B Scan Ultrasound is also very useful and is definitely a better test than CT to evaluate posterior segment structures, but it‟s use in Open
Globe injury on presentation is limited due to the necessity of contact of the probe with the cornea or lid. However following the primary repair it definitely has a role and can even identify some non metallic foreign bodies sometimes missed in the CT
Scan like glass or wood. In fact not doing it in spite of having the facility may have serious medico legal implications. Magnetic Resonance imaging even though can be
75 more sensitive and accurate than CT, is severely limited by the fact that it can‟t be used when we are suspecting a metallic foreign body. But consider a situation where the patient is pregnant and the possibility of a magnetic foreign body is not very high.
MRI may be the answer. When state of the art imaging modalities like the above cannot be employed due to non availability or due to economic reasons then the Plain film Radiograph is still valuable.
Documentation Accurate and methodical documentation of all the relevant details in the history and evaluation is extremely important for clinical and medico legal reasons
Timing of Intervention in Open globe injuries The risk of endophthalmitis does not significantly increase in the first 24 or 36 hours after the injury. So if appropriate equipment ,staff or anesthetist is not available immediately, it is justifiable or even advantageous to wait for a few hours. However if the same is not an issue then it can be done immediately, done within 12 hours. Interventions like lens removal if necessary, IOFB s without much risk of endophthalmitis; repair of retinal detachment etc can be done as a second planned procedure.
Anesthesia General Anesthesia is usually preferred, as it will avoid retro bulbar/peribulbar injections which can induce or aggravate prolapse of intraocular tissues with a lot of undesirable consequences. However systemic risks in some patients; and a lot of practical considerations combine together to result in local anesthesia via the peribulbar or retro bulbar route, still being widely used in many centers. .Topical Anesthesia supplemented by IV sedation can also be used in selected cases .
76
Primary Repair of Injuries Involving Cornea
Self Sealed Corneal Wounds We call them self sealed corneal wounds which on slit lamp examination appears exactly as described by the term with the full thickness wound appearing as an irregular line with good anterior chamber depth , no iris in between the wound lips, rule out the presence of an intraocular foreign body.
As far as primary repair is concerned. Conservative management with only prophylactic antibiotics and no surgical repair is enough for very small self sealed corneal wounds of 2 mm or less ,provided there is no other intraocular tissue at the wound, no other ocular structures are involved , no foreign material is present in the wound and Seidel‟s test is negative. In such cases where it has been decided not to suture, it is always better to place a bandage contact Lens over the cornea and to leave it there for 2-3 wks. Topical Antibiotics and steroids can be continued.
For Larger Self Sealed Lacerations- There are 2 options.
1. Routine surgical repair
2. Cyanoacrylate Tissue glue with Bandage contact Lens.
Corneal Lacerations with Flaps When the wound is not full thickness or only approaching full thickness in a very small area so that it is well sealed, the aim should be to see that whether the flap can be kept well apposed in its correct anatomical location without sutures, as suture in such case may only induce additional astigmatism and may not be of any benefit in the wound healing. So if it is not displaced a bandage soft contact Lens is all that is required. However if the flap is displaced, it has to be repositioned and secured with sutures. In such cases make sure that sutures are partial thickness through the surrounding stroma .The tightness and 77 number of sutures should be just enough to hold the flap in place. Some cases which present late (after 24 hours), may have epithelial growth underneath the flap and this has to be debrided off before suturing. Any way in a displaced flap it is a good idea to irrigate the bed and undersurface of the flap to clean off any debris, foreign body particles etc.
Principles of Surgical repair of Corneal Lacerations
Our aim here should be the restoration of the optically clear, smooth surface and curvature of the cornea as even small irregularities in the curvature can lead to significant visual disability. The plan is of course based on the initial evaluation findings. So during the initial slit lamp examination itself the surgeon should be on the look out for the normal anatomical land marks and other features that will aid in apposing the edges of the wound correctly and restoring the displaced tissues to their correct anatomical location. The idea is that apposition of the edges of the laceration with properly placed sutures should first happen at these land marks. Once this is done correctly the chances of incorrect apposition of the remainder of the laceration are minimal and suturing can proceed smoothly. Such land marks which can be found in a corneal laceration are illustrated in Figure 1 below.
1. Limbus
2. Stellate Edges
3. Pigmentation Lines in the Epithelium
4. Sharp angles of the laceration
78
Figure 9 : Corneal landmarks that facilitate anatomic realignment: the limbus, epithelial pigmentation lines (e.g. iron lines), and stellate would edges/angIes of the wounds(3) (Taken from Text book of Ocular Trauma Principles and Practice-Ferenc
Kuhn; Dante j Pieramici)
It is very unusual to get a corneal Laceration without at least one of the above
.Irrespective of whether he /she has made a plan taking in to consideration all these in the initial evaluation, a reassessment should be done on the table after cleaning off the debris if any from the wound edges and making the wound lips free of any extraneous tissue including iris (by repositioning/abscising as the case may be), vitreous etc.
Based on this a final strategy on how to proceed with the wound repair should be made and executed.
Basic Suturing Techniques
Suturing techniques
Interrupted Sutures The most preferred suturing method to appose the wound edges is interrupted suturing placed with 10-0 or 11-0 nylon with spatulated needle.
Ideally a round suture loop should be placed in a single plane so that the 2 edges will
79 be having a layer to layer apposition. Suture passes should be approximately 1.5 to 2 mm total in length (15) i.e. 0.75 to 1 mm on either side. In case of edematous or macerated wound edges slightly longer passes may be required to incorporate healthy tissue by the suture. Equal amount of tissue should be incorporated on each side of the wound. The depth of the sutures should be 85-90% of full thickness, which would mean that the needle passes over the Descemet‟s membrane. Full thickness corneal lacerations generally have one of the following 2 anatomical configurations .
1. A more or less Vertical (perpendicular) laceration
2. An oblique (shelved or beveled) laceration
The 2 types require 2 slightly different approaches to suturing so as to facilitate correct wound edge apposition without any overriding or distortion. In vertical Lacerations the suture entry and exit sites should be equidistant from the wound margins so that the corneal suture is centered over the wound (See Fig 2).
However we don‟t have to worry whether it is centered with respect to the anterior aspect of the wound or posterior aspect of the wound as both would be in the same perpendicular line. If any of the limbs of the suture is longer than the other, the wound edge on that side will override the other edge when tightened.
80
Figure 10: The distance from the wound margin to the entry site (A) is the same as the distance from the wound margin to the exit site(B) (Adapted from 101 Pearls in
Refractive, Cataract, and Corneal Surgery second edition Edited by Samir A. Melki and Dimitri T. Azar)
In beveled or shelved lacerations a slightly different approach is required.
Here if you are taking the bites equidistant from the anterior aspect of the wound margin, there will be wound overriding and tissue distortion. To prevent this care should be taken to ensure that the suture is centered on the posterior aspect of the wound margin. This means that the suture entry and exit sites will be displaced with respect to the anterior aspect of the laceration but will be equidistant with respect to the posterior aspect. (See Fig 11)
81
Figure 11 : Suturing of a shelved laceration. The distance from the anterior margin of the wound to the suture entry site (A) is not equal to that from the same point to the suture exit site (B). But what matters here is the distance from the entry and exit sites to the posterior margin of the wound (C &D), which is equal (C=D). (Adapted from
101 Pearls in Refractive, Cataract, and Corneal Surgery second edition Edited by
Samir A. Melki and Dimitri T. Azar)
Figure 12 (Top and bottom) The box suture is a compromise structure for an interrupted suture. The suture is placed full thicknes. With tightening, the tissue is compressed but the wound alignment is not altered. The surface effects of the suture are relieved with suture removal, (Taken from Text book of Ocular Trauma Principles and Practice-Ferenc Kuhn; Dante j Pieramici)
Note that ideal depth through which the suture should pass is 90% which should take it just over the Descemet‟s membrane.
An important factor to be taken into account during suturing of corneal lacerations is the issue of edematous wound edges frequently seen when the time gap between the injury and time of suturing is more than a few hours. This results in 2 problems
1.Because of the corneal edema being localized, we may end up with 2 opposing edges differing significantly in thickness .
2. Once the corneal edema decreases in the immediate post op period aided significantly by the topical anti-inflammatory drops that we invariably give, some of the sutures which we thought were of the correct tensile strength and producing good
82 apposition are suddenly found wanting in doing the job they were entrusted with-viz holding the wound edges in close approximation.
A solution suggested by some authors for the first problem is to employ full thickness box suturing (See Figure 12) as when the full thickness of the corneal edges are incorporated in the suture loop ,there is anyway going to be good approximation – almost layer to layer irrespective of whether there is thickness difference or not. To achieve the same approximation with a partial thickness suture in such a situation will require considerable skills from the surgeon. However there is the risk, even though minimal of the suture acting as a conduit, enabling microorganisms or epithelial cells to enter the eye. The 2nd issue has to be kept in mind when the sutures are tightened and that allowance has to be given. Care must be taken to see that the sutures are always placed at right angles to the wound edge to avoid wound slippage (See fig 13).
Tightening of the suture will cause compression of the tissues, but if correctly done there will not be any eversion or inversion of the edges. The tissues on either side of the laceration will be well apposed without any displacement and the chances of slippage later are minimal.
83
Figure 13 : A and B. Sutures should be placed at right angles to the wound at the point of the suture/wound inters section. Sutures at acute angles will cause wound slippage with tightening as illustrated (11) (Taken from Text book of Ocular Trauma
Principles and Practice-Ferenc Kuhn; Dante j Pieramici)
Rowsey-Hay’s Technique of Corneal Suturing and its importance
Restoring the previous corneal curvature by your suturing well that is attempting to recreate the exquisite work of the creator. Our aim should be rather to provide the patient with a central cornea with uniform spherical contour rather than trying very hard at recreating the previous contour. This is facilitated by the Rowsey-
Hay‟s technique of corneal wound closure illustrated in Figure 14
Figure 14: The Rowsey-Hays technique of central wound closure. The periphery of the wound is closed with long tight compressive suture bites. This results in flattening of the periphery and compensatory steepening of the corneal centre. The centre is then closed with short, spaced, minimally compressive suture bites to preserve the central steepening as much as possible. This will result in a flattened periphery with a
84 spherical center.(Taken from Text book of Ocular Trauma Principles and Practice-
Ferenc Kuhn; Dante j Pieramici)
Some sort of a qualitative keratometry can be utilized to ensure that the central corneal curvature is uniform. An easily available instrument in the OT for this will be a Fleringa ring. If that is not available a hinge spring of a safety pin may suffice. After the initial suturing, the surgeon can hold this ring over the cornea and utilizing the co axial illumination, its reflection from the epithelial surface is examined. The ideal reflection should be a round circle. If there is some astigmatism induced, the ring appears oval or distorted. In such case the surgeon can then tighten or loosen some sutures keeping in mind the Rowsey-Hay principle so as to get an ideal reflection.
Special Situations
Loose fragments
Full thickness corneal wounds with a lot of loose fragments often displaced in impossible angles, can be really tough to repair. However all these fragments have to be patiently and meticulously repositioned into their normal anatomic position
.Having done this the next big problem is how to keep them there? As a first step try to place sutures through the edges of the fragments .If it works, good .If not then consider the following additional options
1. Oversewing
2. Using Bandage contact Lens as a splint
3. Glue
85
Stellate Wounds
Next to loss of tissue, this is the most difficult problem in corneal wound repair. They may require a combination of sutures and tissue adhesive, and sometimes, a patch graft for a proper closure. A purse string technique has been proposed by Eisner. In some cases, the additional use of cyanoacrylic glue can be helpful.
Injuries to LASIK Flaps
The corneal flaps created during LASIK are vulnerable to traumatic dehiscence and dislocation, even years after the procedure. A partially displaced flap can be managed with a bandage contact Lens while a completely displaced flap should be repositioned and secured with sutures. It is always better to get the help of a refractive surgeon in these cases
Loss of Tissue
This situation is extremely rare and in most cases the missing piece of the puzzle (tissue) will be there –mostly turned down as a flap into the anterior chamber or just displaced from its normal site. So before allowing the alarm bells to ring, do a careful examination of the full thickness of each of the wound edges, if necessary with the help of a blunt instrument like an iris repositor to detect and reposition such corneal fragments or displaced flaps. Once that is done all that is remaining will be to apply a few well placed sutures.
However wounds with loss of tissue can occur in a few cases of trauma with high speed missiles as in gunshot wounds or explosions. If the defect is small, the
86 area can be closed with tight sutures even though it can result in significant amounts of tissue distortion and wound tension and may later cause significant irregular astigmatism. However when such tissue loss exceeds 5 mm in diameter a corneal patch graft is usually required. Full-thickness patch graft is technically easier to perform but requires a donor cornea. A lamellar patch graft is effective and may be performed with a corneal auto graft or donor sclera. These grafts are often located outside of the visual axis; therefore, graft clarity may not be essential for good postoperative vision
Some general considerations while repairing corneal wounds
1. Handling of tissue should be kept to minimum. Repeated attempts at grasping the wound edges can lead to maceration especially as the tissue might be edematous and fragile. The surgeon will be making his job more and more difficult by doing this
.The spatulated needle point of the 10-0 should be prevented from touching any other tissue other than the wound edge as it can easily get blunt and would make suturing more difficult, there by forcing the surgeon to do just what he should not be doing i.e. grasping and regrasping the tissue. Many a time maintaining the anterior chamber with a tight air bubble lets you do the suturing without needing to grasp the wound edges with forceps or by just fixing the globe gently by grasping at the perilimbal episcleral tissue. An exquisitely sharp spatulated tip for the suture needle is absolutely necessary for this.
2. Options to be considered when wound leak persists in spite of suturing
i. Bandage Contact Lenses
ii. Tissue adhesives 87
iii. Patch graft
3. Avoid putting sutures in the visual axis as far as possible. If unavoidable make sure that the suture limbs are kept very short.
Scleral and Corneoscleral Injuries
The main goals in the management here include
1. Restoration of integrity of the globe
2. Avoidance of Further injury to Ocular tissues
3. Prevention of Corneal scarring and astigmatism
Very small scleral defects as in a puncture wound by a sharp thin wire or the common broom stick, without uveal prolapse can be managed conservatively with appropriate antibiotic therapy. However most of the larger scleral wounds require surgical repair. Unlike the purely corneal injuries, scleral wounds especially ruptures can sometimes be missed since they can be hidden by the intact conjunctiva and /or large subconjunctival hematoma. So there has to be a high index of suspicion in cases with suspicious signs and typical history (see evaluation). Any lingering doubts are to be settled by a globe exploration under the appropriate anesthesia. If necessary a 360 degree peritomy is made as in RD surgery so as to retract the conjunctiva and provide good exposure of the sclera. Special attention is to be given to the areas of muscle insertions and the areas in between them as this is one of the most common sites for a rupture.
General Principles of Closure of Scleral Wounds
88
Full thickness scleral wounds are generally apposed with interrupted sutures with “8-0” or “9-0” Silk or Nylon .A needle with a spatulated end is to be used.
1. Ensure proper exposure and visibility of the wound edges. A common mistake
by many of us is the involvement of the tenon‟s or even the conjunctiva in the
suture supposed to approximate the scleral wound edges .Worse there might
be only tenonsand no sclera. Best way to ensure this doesn‟t happen is to clear
the tenons and conjunctiva completely off the wound edges before passing the
suture
2. Involvement of any prolapsed or prolapsing tissue (uvea, retina or vitreous) in
the suture is also to be diligently avoided. So it follows that any such tissue
must be gently reposited back or abscised away as the case may be before
passing the suture. Vitreous of course should be amputated at the scleral
surface. When doing this any unnecessary traction on the vitreous should be
avoided. The wound edges may be raised gently with forceps while passing
suture bites so as to keep any uveal tissue from being impaled by the suture
needle. Using viscoelastics to reposition uveal tissue in a scleral laceration
may not be a good idea as the viscoelastics may enter the sub retinal space
from where it is only poorly absorbed resulting in excessive inflammation and
increased risk of Retinal detachment.
3. Scleral wounds are generally closed from anterior to posterior direction. Just
as in the cornea here also suturing should begin from a recognizable land
mark. If the Limbus is involved then without doubt that is where the first
suture should go. Otherwise we start from a recognizable landmark like the
apex of the laceration. 89
4. Large wounds extending posteriorly, it is better to employ a “Close as You
Go” strategy as illustrated in Figure 15. Also if you leave the last tied suture
ends long, these ends can be used to exert some traction on the globe so as to
rotate it anteriorly so as to expose more of the posterior portion of the wound.
Figure 15: The “Close as You Go” technique for Exploration and Primary Closure of a Scleral Wound. Here the visible anterior portion of the wound is exposed and sutured first and having reached the visible end a little more of the wound is exposed by opening the conjunctiva and Tenons there and sutures are applied to this exposed area. Having finished this more of the wound is progressively exposed and sutured.
This ensures that the still to be sutured, open part of the laceration is supported by the periorbita and this will prevent the intraocular contents from prolapsing out. . (Taken from Text book of Ocular Trauma Principles and PracticeFerenc Kuhn; Dante j
Pieramici)
5. But even with this method there is a limit to the posterior limit up to which
you can go in a wound extending posterior to the equator. In such cases some
portions of the posterior most portions of the wound might have to be left
90
unsutured. It is better to do so than to cause additional damage and further
tissue prolapse with extreme manipulations.
6. Following the same principles an isolated posterior scleral wound near the
optic nerve may be best left alone unsutured, trusting the surrounding orbital
tissue to give good tamponade as the wound heals.
7. In cases where the scleral wound extends through or under an extra ocular
muscle, an assistant can retract the muscle gently using a muscle hook to aid
in exposure. If more exposure is needed especially if the laceration is under
the insertion of the muscle, the same may need to be temporarily disinserted
so as to allow the suturing. Following the closure of the scleral defect the
muscle may be reinserted. Corneoscleral Wounds We just need to combine the
principles of corneal and scleral wound repair here. Commonsense dictates
that the major landmark here is the Limbus and so that is the area to be
apposed first. Next continue with repair of the corneal aspect followed by the
scleral aspect adhering to the principles already discussed. See Figure 8 for
illustration
Figure 16: Left side fig shows the anatomic Land marks identified in the corneoscleral wound. These are Limbus (1) and the angles of the wound (2, 3). So
91 first suture at (1), then corneal part and then scleral part. (Taken from Text book of
Ocular Trauma Principles and Practice-Ferenc Kuhn; Dante j Pieramici).
Special Situations
Scleral Defects Not repairable by suturing alone This can occur in severe trauma to the globe or even not so severe trauma involving areas already thinned out or weakened by previous infections ; inflammations or degenerations (egstaphyloma in high myopia) .In such cases repair using a scleral patch graft is indicated. Depending upon the size of the defect and need for structural support, a variety of materials can be used for grafting as follows
Table 6: Graft materials in sclera patch graft
Controversies
1. Reconstruction Vs Enucleating in No PL Eyes
The current thinking is that even if the globe appears very badly damaged and vision is NO PL , every effort should be made to preserve the globe in the emergency management setting . In such cases secondary enucleating can be considered if later the eye despite all the reconstructive attempts remain No PL and the risk of sympathetic ophthalmitis is perceived to be higher than usual. The decision can then
92 be taken after discussion with other colleagues and also the patients and relatives. The psychological trauma inflicted on the patient by an enucleation in the acute period can be tremendous and is best avoided.
2. Timing of Primary repair- Immediate Vs Delayed
This has already been discussed. The gist of the matter is that several studies have proved that the risk of endophthalmitis in open globe injuries does not significantly increase in the first 24 or even 36 hours. So if a few hours delay can improve the quality of the surgery and patient care, then it is better that way.
However where the risk of infection is high as in large uveal prolapse ; certain types of Intra ocular foreign bodies such a delay may not be prudent.
3. Primary Wound Closure Vs Comprehensive Reconstruction
In the former the primary management is limited to a proper wound toilette; management of the prolapsed intraocular tissue (repositioning or abscising) ;
Removal of any obvious anterior chamber and wound lip foreign bodies and apposition of the wound by suitable sutures. The advantages are that things are kept very simple requiring only average skill and expertise. A thorough evaluation can be carried out in the post operative period including B scan; CT scan and even electrophysiology and further management involving complicated procedures like
Vitreo -Retinal procedures can be planned and executed in consultation with other colleagues or even other centers. On the other hand a truly comprehensive management involves tackling the other co existing pathologies like cataract,
Posterior segment IOFB , Posteriorly dislocated Lens or IOL, Retinal detachment
Vitreous hemorrhage etc and depends on the availability of ophthalmologists who are
93 fully trained to work in the anterior as well as the posterior segment of the eye or a comprehensive team of Anterior and Posterior Segment surgeons along with the proper infrastructure and technical support.
So even though the first is definitely more practical and also the only option in many centers, the latter approach has some advantages some of which are as follows
1) Comprehensive management is less expensive.
2) Comprehensive management offers potential prevention of endophthalmitis by removing the inoculated media (eg an Intravitrealnon metallic foreign body)
3)Comprehensive management offers the potential reduction of post-injury inflammation and the prevention of scar tissue formation, such as proliferative vitreoretinopathy (PVR), again by removing stimulating factors (cytokines) present in the vitreous cavity.
4) Comprehensive management offers earlier visual rehabilitation
Research is still going on in this field and may ultimately settle this question in favour of one of the approaches.
4. Role of Prophylactic Cryotherapy in Corneoscleral Injuries
Prophylactic cryo done by a few surgeons in the hope that it might prevent a retinal detachment. However this might be counterproductive as it may trigger increased intraocular inflammation and fibrosis thereby increasing the chance of a detachment . If retinal view is there a barrage laser should be considered.
5. Role of Prophylactic Scleral Buckle
94
Despite numerous studies, there are no substantial data to indicate whether a scleral buckle might decrease the subsequent risk of retinal detachment or even reduce the need for secondary surgical intervention. However, if the scleral and retinal laceration extends posterior to the oraserrata, if the peripheral retina cannot be visualized, and in case of retinal incarceration, a prophylactic scleral buckle should be considered.
Management of Intraocular Foreign Bodies
Given the risk of endophthalmitis, prompt evaluation and treatment are essential. But even when managed properly, IOFBs associated with traumatic eye injuries may lead to severe vision loss. While foreign objects can be composed of almost any substance, most are metal, glass, wood, stone, etc. Intraocular foreign bodies (IOFBs) may become embedded in any ocular structure, from the anterior chamber to the retina. Given the risk of endophthalmitis, prompt evaluation and treatment are essential.
Evaluating the Patient
IOFBs should be suspected in all open globe injuries. The preoperative evaluation should include a focused history to determine the time and mechanism of the injury along with detailed information about the composition of the object. it is important to note whether the injury occurred in the workplace and whether the patient was wearing protective eyewear when the injury occurred.
A careful ocular examination, minimizing pressure to the globe to avoid further expulsion of its contents, is essential. If the view to the posterior pole is
95 limited, gentle B-scan ultrasonography to ensure that no pressure is applied to the globe.
CT scans may aid in identifying objects and further evaluating the globe, orbital bones and retrobulbar space. False-negative CT results may occur with IOFBs that are small or of wooden, vegetable, plastic or ceramic content. MRI is contraindicated in the presence of a metallic object.
Indications for Removal
As a general rule, if the IOFB is accessible, then removal is the best option
Moreover, some IOFBs can be tolerated when left in the eye, including those made of glass, plastic, pencil lead (graphite), stone, aluminum or gold. However, metal objects with low redox potential or objects contaminated with organic matter can cause significant morbidity. Issues to consider include the following:
Toxicity. Metallic objects consisting of iron, lead or copper and its alloys should be removed because of well documented toxic effects on intraocular tissues.
For instance, siderosis bulbi, caused by intraocular toxicity from ionized iron, is characterized by a rust colored corneal stroma, iris heterochromia with brownish- discoloration, a dilated and nonreactive pupil, orange deposits in the lens epithelium and anterior cortex, and retinal degeneration. The toxic effects of copper in the eye depend on the percentage of copper in the IOFB. Acute chalcosis occurs with metals with a copper content of 85 percent or more and is characterized by sterile endophthalmitis, corneal and scleral melting, hypopyon and retinal detachment. Other clinical findings include a Kayser-Fleischer ring, iris heterochromia with greenish discoloration, a “sunflower” cataract and retinal degeneration. Chronic chalcosis may 96 be seen with metals containing less than 85 percent copper, but this finding rarely leads to blindness.
Contamination. In an outdoor setting, IOFBs are often contaminated with vegetable matter, increasing the risk of infectious endophthalmitis.
Management
The goal in managing an IOFB is to achieve the best visual outcome possible by identifying and closing the entry and exit sites, reconstructing the eye and, and removing the object.
Ideally, an IOFB should be removed within 24 hours of the time of injury, and the object and the surrounding ocular tissue should be sent for culture, to prevent endophthalmitis.
Most IOFBs are extracted from a new opening unless the entrance wound is large. Two types of instruments are used: an intraocular magnet and a forceps. The choice of instrument depends on the foreign body. A magnet can remove an object of any size, shape and weight with a ferrous content. For other IOFBs, a variety of forceps may be required depending on the object‟s size and shape.
The surgical approach depends on the object‟s location in the eye:
Anterior chamber placement. The anterior chamber is maintained with viscoelastic.
If the object is visible, a limbal incision can be made over the object. Alternatively, an incision is created 90 to 180 degrees from the object for better access with forceps.
97
If the IOFB is hidden in the angle, an endoscope, inserted through an incision
180 degrees from the object, may be used for visualization. And the IOFB may be removed with a magnet or forceps through an incision created 90 degrees from the object.
Intralenticular placement. An inert IOFB embedded in a lens with no cataract may be observed. The lens may or may not be salvageable after the object is removed.
If a cataract is present, the lens may be removed during primary or secondary repair. If the lens is removed, IOL placement should be deferred when vitreoretinal damage is suspected, since an IOL may interfere with the view of the posterior segment. IOL placement should also be deferred when endophthalmitis is present or is at high risk of developing. If an IOL will be placed during primary repair, the integrity of the lens capsule and its zonules should be evaluated.
Posterior segment placement. A hyphema, cataract or vitreous hemorrhage that interferes with the view to the posterior segment should be removed. If the IOFB is visible and free-floating in the vitreous cavity, a pars plana vitrectomy with removal of the object with a magnet and/or forceps may be attempted. A 20-gauge pars plana vitrectomy is the preferred procedure. However, a smaller-gauge vitrectomy may be feasible in cases involving an object between 0.3 and 0.5 mm in diameter in a globe that can tolerate elevated IOP.
The posterior hyaloid is detached and removed to eliminate any tractional component, and vitreous strands and or the fibrous capsule of the IOFB are released to facilitate its removal. Enlarging a pars plana incision site allows for extraction of the object.
98
Figure 10: Granite foreign body in a stone cutting mason
99
METHODOLOGY
Source of Data
The materials for the present study will be drawn from patients attending outpatient department of ophthalmology and casualty at KIMS HUBLI with open globe ocular injuries from January 2016 to December 2016,who meet the inclusion and exclusion criteria of this study.
Inclusion Criteria:
All patients with open globe injury presenting to Karnataka institute of medical sciences
Hospital between January 2016 to December 2016.
Exclusion criteria:
The following patients of open-globe injuries will be excluded from the study:
1. Patients presenting with unstable vital signs and/or altered sensorium.
2. Patients presenting with associated severe maxillo-facial injuries.
3. Eyes with previously impaired vision
4. Patients refusing admissions.
Outcome Measure
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The outcome measure was the final visual acuity (six months after the primary surgical procedure). The case would be excluded for outcome analysis if the follow-up period was less than six months after the primary surgery. Those eyes which underwent destructive procedures or those with phthisis documented at follow-up were not excluded, even if the follow-up period fell short of six months as there would not be a change in their visual acuity.
Data Collection
All patients selected for the study underwent a complete ophthalmic examination and the findings were recorded in a Performa. A list of the presence or absence of the prognostic factors being studied was recorded prior to surgery. Along with a case history (including situation and source of injury) and ocular findings the following was recorded for all patients:
1. Identification (serial number, chart number and name)
2. Demographic data (age, sex, rural/urban location)
3. Injury data (work related, left/right eye)
4. Ocular data (initial visual acuity, grade, type, zone and pupil status)
5. Details of open globe (laceration length, hyphaema, retinal status)
6. Surgery details (duration from injury, nature of surgery)
7. Follow up details (final visual acuity, follow-up diagnosis)
8. Second surgery details (if present: reason, nature of surgery)
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SAMPLE SIZE OF ESTIMATION
All patients with open globe injury presenting to Karnataka institute of medical sciences
Hospital between January 2016 to December 2016 who met the inclusion and exclusion criteria are included in the study.
The data was charted on a spread sheet, and all factors were subjected to primarily analysis using the software SPSS (ver. 20.1) to see if the outcome resulted in visual impairment.
Statistical analysis
SPSS version 20 was used for statistical analysis.
Descriptive statistics were calculated.
The tabulated data was regrouped (to overcome sparse cell counts) and subjected to a univariate analysis (Chi squared test) and Fisher exact test.
The factors which had a statistically significant association with the final visual acuity were subjected to a final scoring pattern to determine their collective importance in determining the visual outcome
Association was studied using Chi square test.
A p value < 0.05 was considered to be significant.
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RESULTS
A total of 38 open globe injuries were treated by the Department of Ophthalmology in Karnataka institute of medical sciences (Hubli) during the one year period (1st January 2016 to 31st
December 2016). All 38 cases (100%) met the inclusion criteria and were included in the study..
The details of the patients will be presented as epidemiology, clinical presentation, details of surgery and follow-up data with visual outcome analysis.
Age group Number Age group Number
0 to 5 0 36 to 40 5
6 to 10 2 41 to 45 2
11 to 15 4 46 to 50 4
16 to 20 2 51 to 55 0
21 to 25 3 56 to 60 3
26 to 30 8 61 to 65 2
31 to 35 3 65 to 70 0
Table 7: Age distribution frequency
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Figure 18: Age distribution of thirty-eight patients with a bar graph
Epidemiology
Demographic Data:
In the total study population of 38 patients, the mean age was 33.89 years (median of
32years, ranging from 8 years to 62 years). 28 (73.68%) were males, and 10 (26.31%) were female. The frequency table for age shows a peak in the age range of 26 to 30 years (see Figure
18). Out of 38 total patients , 22(57.89%) patients were from rural background. 16(42.10%)
patients from urban background.
104
Figure 19: Sex distribution of open globe injuries.
Figure 20: Background distribution of open globe injuries
105
Cause of Injury:
Agriculture linked injuries accounted for 15 injuries (39.4%). The injuries occurred in an industrial setting accounted for 7 injuries (18.4%), while the others occurred on a street/highway/road traffic accidents accounted for 5 injuries (13.15%), at school accounted for
5 injuries ( 13.5%). Injuries at home were 4 (10.5%), or assault related injuries accounted for 2
(5.2%) (see Figure 21).
Figure 21: Location of occurrence of injury.
Intent of Injury:
Most of the injuries 36 (94.73%) were unintentional, while the other 2 (5.2%) injuries were the result of assault.
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Source of Injury:
The source of injury was a metallic object in 10 cases (26.31%), consisting of metal shrapnel, spring and nail. Wood piece, broomstick, and thorn in 9 cases (23.6%) The other sources of injury included stones and gravel in 6 cases (15.7%), Glass was the source of injury in
3 cases (7.8%). The source of some blunt forces causing a globe rupture included 3 (7.8%) bull gore injury, 2 injuries (5.26%) were due to a hand or fist. The source of five injuries (13.15%) remained unknown.
Use of Eye Protection:
Three of the 38 patients (7.8%) said that protective wear was available in the premises during the time of injury, but none of them had worn any form of protection when they were injured.
Alcohol Consumption:
Only 2 patients (5.2%) were under the influence of alcohol during the time of injury.
There was no history of alcohol consumption in the occupational group.
Clinical Presentation
Eye Involved:
The right eye was affected in 20 patients (52.66%) and the left eye in 18 patients
(47.36%). None of the cases suffered from bilateral open globe injuries
107
Figure 22: Eye involved in injury.
Association with Other Injuries:
Open globe injuries were associated with injuries to other parts of the face in 3 cases
(7.8%) and other parts of the body in 2 more cases (5.2%).
Ocular Examination:
The visual acuity at presentation, presence of an afferent pupillary defect, zone of injury and type of injury were noted in all patients and classified according to the ISOT classification of open globe injuries .Their incidences have been listed in Table 8.
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GRADE TYPE ZONE PUPIL
% % % %
No No No No
1 3 7.89 A 8 21.05 1 17 44.7 Neg 26 68.4
2 4 10.52 B 19 50.00 11 11 28.9 Pos 12 31.5
3 8 21.05 C 11 28.94 111 10 26.3
4 17 44.73 D ---
5 6 15.78 E ---
Table 8: Frequency table for the visual acuity at presentation, presence of an afferent pupillary defect, zone of injury and type of injury
Lid oedema was present in 4 patients (10.52%), lid abrasions in 1 patient (2.6%), and lid laceration in 10 patients(26.31) , 4 patients (10.52%) without involvement of the lid margin, and
6 patients (15.78%) with involvement of the lid margin. Orbital fractures were present in 2 patients (5.26%). The lids and adnexal tissues were not involved in (22 patients; 57.89%).
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The mean corneal laceration was 3.97mm, median 5mm The mean scleral laceration was
4.57mm ,median 2.5mm The mean total length of the globe laceration (including both cornea and sclera) was 8.55mm (median: 7mm;). The cornea was spared in 10 patients (26.31%), a single (linear) corneal laceration was present in 13 patients (34.21 %), single irregular laceration in 11 patients (28.91%) and multiple corneal laceration in 3 patients (7.89%).
Hyphaema was present in 10 patients (26.3%), 7 patients (18.42%) with a hyphaema
50% or more and 3 patients (7.8%) with a hyphaema of less than 50%.The lens was found to be opaque at presentation in 17 patients (44.73%), subluxated in 2 patients (5.2%) and dislocated in
1 patient (2.6%)
. The sclera was not involved in 18 patients (47.36%), while a single (linear) scleral laceration was present in 5 patients (13.15%), single irregular laceration in 10 patients (26.31%) and multiple scleral lacerations in 6 patients (15.78%). Vitreous haemorrhage was detected pre- operatively in 4 patients (10.52%) and a vitreous haze was detected in 6 patients (15.78%). The status of the retina was not assessed preoperatively in 8 patients (21.05%) due to media opacities. Retinal detachment was found in 3 patients (7.8%), one with macula involved.
Choroidal rupture was detected in 1 patient (2.6%).
Of the 11 patients who had intraocular foreign bodies, the final location of the foreign body was the anterior segment in all 11 patients (28.94%). In total, 3 metal foreign bodies
(7.89%) were present, while 3 were stone (7.89%), 3 foreign bodies (7.89%) were wood and 2 was a broomstick (5.26%).
Details of Surgery: The mean duration between the injury and surgical intervention was 31.78 hours (median: 20 hours; mode of 16 hours;). 35 patients underwent primary reparative surgery.
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Six patients underwent anterior vitrectomy only. Intraocular lenses were implanted in the secondary procedure in 14 patients .11 patients (26.63%) underwent foreign body removal. Of the 3 metallic foreign bodies removed from the anterior segment without a magnet.
Follow-Up Data
The mean duration of follow-up was 9±3months (ranging from 6 months to 12 months).
Of the 38 cases followed up, 21 cases (55.26%) had a visual acuity of 6/18 or better, fulfilling the WHO definition for mild or no visual impairment.68 (See Table 9)
WHO Category Visual Acuity No %
0. Mild or no visual impairment 6/18 or better 21 55.26
1. Moderate visual impairment 6/19 to 6/60 7 18.4
2. Severe visual impairment 6/60 to 3/60 0 0
3. Blindness 3/60 to 1/60 2 5.26
4. Blindness 1/60 to light perception 1 2.63
5. Blindness No light perception 7 18.4
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Table 9: Visual outcome classified according to classification of visual impairment bythe World
Health Organisation68
Of those who did not achieve a vision of better then 6/18, 3 had corneal scars
(17.6%),and 1 had posterior capsular opacities (5.88%). In those patient who were followed up, the irreversible causes of reduced visual acuity were retinal damage in 6 patients (35.29%), phthisis in 4 patients (12.24%) and 3(17.6%) eyes that have undergone destructive procedures,
(Eviscerated). Secondary procedures were required in 14 cases.
Outcome Analysis : The outcome measure was the final visual acuity (six months after the primary surgical procedure). The eyes which underwent destructive procedures or those with documented phthisis were not excluded, even if the follow-up period fell short of six months as there would not be a change in their visual acuity.
Outcome Analysis
(38 patients)
Factor Variable No. %
Follow-Up Visual Acuity 6/18 or better 21 55.2
Worse than 6/18 17 44.7
Table 10: Frequency table for the outcome measure
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Figure 23: Follow up visual acuity ( pie chart)
The outcome was analysed with respect to the following factors:
1. Epidemiological factors (age , sex, rural/urban location, work related)
2. Injury Factors (left/right eye, initial visual acuity, grade, type, zone and pupil status)
3. Associated factors (length of wound, hyphaema, retinal status)
4. Surgical factors (duration from injury, second surgery done/not done)
To ensure that the cases excluded did not result in a bias, we compared each of the analysed factors of the outcome group with the total group. We found the difference to be statistically insignificant in every factor (p > 0.05).
113
Epidemiological factors: We compared the final visual acuity with each of the epidemiological factors and found all the factors to be statistically insignificant as prognostic factors. The details of the analysis are given in Table 11.
Final Visual Acuity
6/18 or better Worse than 6/18
Age No. % No. %
12 yrs or less 3 100 0 0
More than 12 yrs 18 51.4 17 48.57
Sex No. % No. %
Male 13 46.4 15 53.57
Female 8 80 2 20
Residence No. % No. %
Rural 13 59.09 9 40.9
Urban 8 50 8 50
Work Related No. % No. %
No 12 52.17 11 47.8
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Yes 9 60 6 40
Table 11: Significance of age, sex, residence and relation to work as prognostic factors.
A) Age ;The Fisher exact test statistic value is 0.238265. The result is not significant at p < .05.
B) Sex; The Fisher exact test statistic value is 0.136493. The result is not significant at p < .05.
C) Residence; The chi-square statistic is 0.3097. The p-value is .577894. This result is not
significant at p < .05.
D) Work related ;The chi-square statistic is 0.2249. The p-value is .635318. This result is not
significant at p < .05.
Figure 24: Significance of age, sex, residence and relation to work as a prognostic Factors
(Bar Chart) showing final visual acuity
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Injury Factors:
We compared the final visual acuity with each of the injury factors. Grade, zone and type of injury were divided into two groups each and compared. This was done because of the sparse counts found in some cells. The laterality of injury was statistically insignificant as factors for prognosis. The zone of injury was statistically very significant in predicting a favourable outcome, however the statistical significance was poor when it was grouped (Isolated corneal vs.
Scleral). The grouping was essential due to sparse cell counts.
The grouped variable of grade (3 or less vs. more than 3) was statistically significant as a prognosticating factor. The grouped variable of type (A vs. B and C; ie: Blunt vs. Sharp) was statistically significant as a prognosticating factor. Pupil (positive vs. negative) was statistically significant as a prognosticating factor.
The details of the analysis are given in Tables 12 to 16.
Final Visual Acuity
6/18 or better Worse than 6/18
Eye No. % No. %
Right 12 60 8 40
Left 9 50. 9 50
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Table 12: Significance of right /left eye as a prognostic factor .The chi-square statistic is
0.3832. The p-value is .535899. This result is not significant at p < .05.
Figure 25 : Significance of left or right eye as a prognostic factor (bar chart)
Final Visual Acuity
6/18 or better Worse than 6/18
Grade No. % No. %
1 3 100.0 - -
2 4 100.0 - -
3 6 75.0 2 25.0
4 8 47.05 9 52.94
5 - - 6 100
Table 13: Significance of grade of injury as a prognostic factor The chi-square statistic is
9.8856. The p-value is .001666. This result is significant at p < .05. Note: Grouped as 1 to 3 grades vs. grades 4 and 5 due to sparse cell count.
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Final Visual Acuity
6/18 or better Worse than 6/18
Type No. % No. %
A 2 25 6 75
B 12 63.1 7 36.8
C 7 63.6 4 36.36
Table 14 : Significance of type of injury as a prognostic factor The Fisher exact test statistic value is 0.106576. The result is not significant at p < .05. Note: Grouped as type A (blunt) vs. types B and C (sharp) due to sparse cell counts. No type D and type E injuries were seen.
Final Visual Acuity
6/18 or better Worse than 6/18
Zone No. % No. %
I 14 82.3 3 17.6
II 6 54.4 5 45.5
III 1 10 9 90
Table 15: Significance of zone of injury as a prognostic factor
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Grouped;The chi-square statistic is 9.1311. p-value is .002513.This result is significant at p < .05
Ungrouped; The chi-square statistic is 13.3353. The p-value is .001271. The result is significant at p < .05.
Note: Grouped as zone I (corneal) vs. zones II and III (scleral) due to sparse cell count
Final Visual Acuity
6/18 or better Worse than 6/18
Eye No. % No. %
Negative 20 76.9 6 23.07
Positive 1 8.3 11 91.6
Table 16: Significance of pupil as a prognostic factor.
The chi-square statistic is 15.6239. The p-value is .000077. This result is significant at p < .05.
Associated Factors:
We compared the final visual acuity with each associated factor. Hyphema and retina score were divided into two groups each and compared. This was done because of the sparse counts found in some cells. Hyphaema (less than 50% vs. more than 50%) was statistically insignificant as factor for prognosis. The grouped variable of retina (attached retina v detached retina) was statistically significant as a prognosticating factor. The length of the wound (10mm
119 or less vs. more than 10mm) was statistically significant as a prognosticating factor. The details of the analysis are given in Tables 17 to 19.
Final Visual Acuity
6/18 or better Worse than 6/18
Length of wound No. % No. %
10mm or less 22 75.8 7 24.1
More then
10mm - - 9 100.0
Table 17: Significance of length of wound as a prognostic factor The Fisher exact test statistic value is 7E-05. The result is significant at p < .05.
Final Visual Acuity
6/18 or better Worse than 6/18
Hyphaema No. % No. %
50% or less 21 60 14 40
120
More than
50% 0 0 3 100
Table 18: Significance of hyphaema as a prognostic factor .The Fisher exact test statistic value is 0.080607. The result is not significant at p < .05.
Final Visual Acuity
6/18 or better Worse than 6/18
Retina No. % No. %
Attached 19 73 7 27
Detached 0 4
Not Visible 2 16.6 6 83.3
Table 19: Significance of retinal status as a prognostic factor .The chi-square statistic is
10.5678. The p-value is .001151. This result is significant at p < .05. Note: Grouped as (attached retina) vs. (detached or not visible) due to sparse cell count.
Surgical Factors:
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We compared the final visual acuity with each surgical factor. We analysed the roll of the time duration between injury and surgery in detail. When we analysed the outcome of those injuries that were operated within a 24 hours period and outside the 24 hours period we found that the difference was statistically significant .
The requirement for a second surgery was statistically insignificant in predicting the visual outcome. The details of the analysis are given in Tables 16 and 17.
Final Visual Acuity
6/18 or better Worse than 6/18
Delay of
Surgery No. % No. %
Less than 24 hrs 21 84 4 16
24 hrs or more 0 0 13 100
Table 20: Significance of delaying surgery more than 24 hours as a prognostic factors The
Fisher exact test statistic value is 0. The result is significant at p < .05.
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Final Visual Acuity
6/18 or better Worse than 6/18
Second Surgery No. % No. %
No 15 62.5 9 37.5
Yes 6 42.85 8 57.14
Table 21: Significance of the requirement for a second surgery as a prognostic Factor The chi-
square statistic is 1.38. The p-value is .240109. This result is not significant at p < .05
Pre-operative scoring of an Open Globe Injury:
Each factor associated with the ISOT classification of open globe injuries was put together in the format of a score and analysed. Each factor was assigned a score (0 or 1) and the combination of these were then compared with the final visual outcome. The scores for each of the factors are described in Table 18.
FACTOR 0 1
GRADE 1 TO 3 4 OR 5
TYPE B AND C (SHARP INJURY) A (BLUNT INJURY)
ZONE 1 (ISOLATED TO CORNEA) 11 AND 111 SCLERAL
123
PUPIL NEGATIVE POSITIVE
Table 22: Scoring system based on the ISOT classification of open-globe injuries.
The scoring system was tested first with all four factors and found to be very significant in the prognosis of open globe injuries. The details of this are as described in Table 23.
Final Visual Acuity
6/18 or better Worse than 6/18
Score No. % No. %
0 9 81.8 2 18.18
1 8 88.8 1 11.1
2 2 40 3 60.0
3 2 28.5 5 71.4
4 0 - 6 100
Table 23: Results of the scoring system using all the four factors (grade, type, zone and pupil)
Results of the scoring system score 0,1,2 grouped vs score 3 & 4 using all the four factors(grade,
124 type, zone and pupil) (p < 0.05) due to sparse cell count. The chi-square statistic is 16.087. The p-value is .001088. The result is significant at p < .05.
Pre operative Ocular trauma score OTS grades (Table 24)
OTS grade OTS RAW SUM Frequency Percentage
SCORE
1 0-44 6 15.7
2 45-65 9 23.68
3 66-80 9 23.68
4 81-91 11 28.94
5 92-100 3 7.8
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Figure 26: Pre operative Ocular trauma score OTS grades (Bar chart) Most of patients were of
OTS grade 4 , followed by grade 2 ,3, 1 and 5 .
Association of variable in OTS score with final visual outcome
Presence of RAPD : All the patients with RAPD had OTS grade 1 or 2
Presence of retinal detachment: All the patients with retinal detachment had OTS grade 1 or 2
Presence of blunt injury
All the patients with blunt injury had OTS grade 1 or 2 or 3
Comparison of prognostic value of OTS grading system
All cases with OTS score category 1 with score of 0-44 had NO PL
Category 1 Predicted by OTS Findings in present study
No light perception 74% 6 (100%)
Light perception/ hand motion 15% -
<6/60 7% -
6/60-6/15 3% -
> 6/12 1% -
Table 25 : OTS predicted final visual acuity of category 1
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Cases with OTS score category 2 with score of 44-65
Category 2 Predicted by OTS Findings in present study
No light perception 27% 1 (11.1%)
Light perception/ hand motion 26% 1(11.1%)
<6/60 18% 2 (22.2%)
6/60-6/15 15% 5 (55.5%)
> 6/12 15% -
Table 26 : OTS predicted final visual acuity of category 2
Cases with OTS score category 3 with score of 66-80.
Category 3 Predicted by OTS Findings in present study
No light perception 2% -
Light perception/ hand motion 1% -
<6/60 15% -
6/60-6/15 31% 8 (88.8%)
> 6/12 41% 1 (11.1%)
Table 27 : OTS predicted final visual acuity of category 3
127
Cases with OTS score category 4 with score of 81-91 .
Category 4 Predicted by OTS Findings in present study
No light perception 1% -
Light perception/ hand motion 2% -
<6/60 3% -
6/60-6/15 22% 7 (63.63%)
> 6/12 73% 4 (36.36%)
Table 28 : OTS predicted final visual acuity of category 4
All cases with OTS score category 5 with score of 92-100 had visual acuity of >6/12
Category 5 Predicted by OTS Findings in present study
No light perception 0 -
Light perception/ hand motion 1% -
<6/60 1% -
6/60-6/15 5% -
> 6/12 94% 3 (100%) Table 29 : OTS predicted final visual acuity of category 5
128
Figure 27 : Zone 1 injury
Figure 28 : Lens Disruption.
129
Figure 29 : Zone 1 injury with iris prolapsed.
Figure 30 : Zone I injury: Siedel’s Test – Positive
130
Figure 31 : Globe Rupture with Phacocoele
Figure 32: Zone 2 injury with iris prolapsed
131
Figure 33 : Zone 3 injury
Figure 34 : Traumatic cataract
Figure 35 : Subluxation of lens
132
DISCUSSION
Introduction
In our prospective analysis of patients with open globe injuries, we see that 21 patients
55.26% achieved a final acuity of 6/18 or better (after an average follow-up of (6+3=9) months), fulfilling the WHO criteria for no or mild visual impairment.68 Compared to literature published within the last two decades, the visual outcome of our study is inferior to that published in western literature.30,69 However the results are comparable with Indian reports33,70. Eagling
(1976)69 reported that 62% of those with open globe injuries resulted in a final visual acuity of at least 6/12 and with the advent of modern vitreoretinal surgical techniques, de Juan et al (1983)30 reported that 71% of patients with penetrating injuries had a final visual acuity of 6/18 or better.
Gothwal et al (1999)33 reported that with the present microsurgical capabilities in India, prompt and meticulous surgical treatment restored vision to 6/18 or better in 60.5% of patients.
Epidemiology
Demographic data:
In our case series of 38 patients, the mean age was 33.89 years. The frequency shows a peak in the age range of 26 to 30 years. This is similar to the findings of international 24, 61 and
Indian studies.22,23,51 All the studies have shown that males are more prone to injuries. Our case series showed a higher male preponderance 28 (73.68%) males and 10 (26.31%) females when compared to other national22,23,51 and international studies.24,61 Our study represents the rural and urban population of Hubli & Dharwad district and north Karnataka districts of South India, as
22 (57.89%) are rural background and 16 (42.10) are from an urban background.
133
Cause of Injury:
Occupationally linked injuries accounted 57.8% of the injuries in our study. out of which agriculture related injuries 15 cases (39.4%) and industrial related injuries 7 cases (18.4%).
Liggett et al (1990) from USA have reported that only 8% injuries occurred at work.24 Indian studies in general report more occupationally linked injuries when compared to the western literature, but the proportion was higher in our study.22,51 Our series shows an incidence of agriculture related injuries 15 cases (39.4%).
Intent of Injury:
In our series, 2 cases (5.2%) of the injuries were linked to assault with getting injured by
24 a hand or fist. In the case series by Liggett et al assault accounted for 41% of the injuries.
Source of Injury:
In a study of penetrating eye injuries by Mukherjee et al (1984) the injuries were classified according to the source and it was found that 33% of the injuries were by a metallic
34 object, 23% by a wooden object, 12% by glass and 15% by a stone. In our series, the source of injury was a metallic object in 10 (26.31%) glass in 3 (7.8%), stones and gravel in 6 ( 15.7.)% and organic (wood piece, broomstick, and thorn) in9 (23.6%), while the exact source of injuries in 5 (13.15%) was unknown.
Use of Eye Protection:
None of the cases in our series used protective eyewear although protection was available in 3(7.8%) of the cases. The importance of wearing protective eye wear was stressed by Vasu et
134
63 al (2001) in their retrospective study of occupational open globe injuries. They noted that
76.74% were not wearing protective eyewear at the time of injury. For the prevention of occupational eye injuries, the World Health Organisation recommends improving the features of machines, providing adequate illumination, good selection workers and, most significantly,
71 encouraging the use of protective devices.
Alcohol Consumption:
2 (5.2%) were under the influence of alcohol during the time of injury in our series.
There was no history of alcohol consumption in the occupational group. This differs from the
63 finding of Vasu et al (2001) who noted that 14% were under the influence of alcohol.
Clinical Presentation
Eye involved:
Ligget et al found that 11% of all ocular injuries were bilateral, while 43% sustained
24 injuries to the right eye only and 45% to the left eye. Bilateral open globe injuries are common
63 in injuries associated with the mining industry, usually due to an accidental dynamite blast. A bilateral injury is usually the result of significant force and is therefore related to a poor vision.
We did not have any patients with bilateral injuries in this series. Although, the right eye 20
(52.66%) was affected more often than the left eye 18 (47.36%), we found no significant difference in their outcome.
Association with Other Injuries:
135
The eye has been found to be more prone to injuries, despite it accounting for only 0.1%
45 of the entire frontal surface area of the body. This has been attributed to the preferential exposure of the head during various activities. In our series, open globe injuries were associated with injuries to other parts of the face in 3 (7.8%) and other parts of the body in 2 (5.2%).
Multiple injuries usually signify a more severe force causing the injury. We did not analyse this further due to the small numbers.
Nature and Extent of Ocular Involvement
The initial visual acuity, the type of injury, the location of injury and the presence or absence of a relative afferent pupillary defect have been identified by The Ocular Trauma
18 Classification Group as important variables in the description of an ocular injury. These four specific variables of ocular injuries have been previously identified by a number of retrospective reviews as being important factors of prognostic significance. We studied these factors in detail to establish their importance in the prognosis of open globe injuries.
Grade of Injury:
Various retrospective reviews have shown that visual acuity at presentation has been the single most significant factor in predicting the final visual acuity in an open globe injury.15,30,42,43
The outcome of grade 1 and grade 2 injuries showed that all of them had mild or no visual impairment at the end of 6 months. All grade 5 injuries had a final visual acuity of worse than
6/18. In a retrospective study, Pieramici et al (2003) found that the final visual acuity of up to
13 20/40 was achieved in 95% of those with grade 1 injuries, and 75% with grade 2 injuries. Our study results appear to have better results for the first two grades, but as our study population
136 consists of only 38 cases (as compared to 150 patients by Pieramici et al) we cannot place much importance on that.
Figure 36: Bar chart showing the outcome of the different grades of injury
For analytical purposes, we grouped the cases into those having grade 1 to 3 injuries in one group and those with grade 4 and 5 in the second group and found that the grade of injury at presentation was very significant p-value is <.001666. in its association with final visual acuity.
With a study population of 38 cases the individual groups did not have adequate cell counts.
Hence grouping of these was essential for statistical analysis.
Presence of a Relative Afferent Pupillary Defect:
Pieramici et al (2003) noted that the pupillary response was not recorded in 14% of the eyes retrospectively studied by them.13 In the retrospective analysis of the 453 patients by de
137
Juan et al (1983) the afferent pupillary response was documented in only 97 patients (21%).30
Our study, being prospective, the presence of a relative afferent pupillary defect was looked for with the swinging flashlight test in all the cases. This was possible because none of our patients had bilateral efferent pupillary defects and none of them were monocular with the only eye injured.
Figure 37: Bar chart showing the outcome with and without a relative afferent pupillary defect
In our case series, 11(91.7%) cases of those who presented with a relative afferent pupillary defect had a final vision of worse than 6/18. The presence of relative afferent pupillary defect was found to be statistically very significant (P < .000077) in predicting the outcome, with the
“pupil negative” (without an afferent pupillary defect) group having the best prognosis.
Type of Injury:
138
In the analysis of type of injury,19 ( 50.0%) of the injuries belonged to type B
(penetrating injury), 11 (28.94% )were of type C (intraocular foreign body) and 8 (21.05%) belonged to type A (globe rupture). We did not have any type D or type E injuries. Type A injuries resulted in the worse prognosis with 75.0% of the cases having moderate to sever degrees of visual impairment after six months.
Figure 38: Bar chart showing the outcome of different types of injury
Sharp vs. Blunt Force Injuries:
With a small study population the individual types of injury did not have adequate numbers. Hence grouping of these was essential for statistical analysis. We grouped them and compared sharp injuries (type B and C) against blunt injuries (type A). In our case series we found that 12 (63.1%) of the type B injuries and 7(63.6%) of type C injuries had a vision of 6/18
139 or better, while only 2 (25.0%) of type A injuries achieved the same. The analysis showed statistically insignificant difference between blunt and sharp injuries. Sharp injuries resulted in a better outcome when compared to those with a blunt force.
Our results agree with the existing evidence. Most observers have concluded that blunt injuries carry a worse prognosis when compared to injuries with a sharp agent.30,42,44 In their retrospective analysis of the IOTC classification of open globe injuries, Pieramici et al (2003) showed that type B injuries (penetrating injury) carried the best prognosis while type A injuries
(globe rupture) were 4 times more likely to result in a poor final visual acuity.13 Our results concur with their hypothesis that a more diffuse injury causes a force to be transmitted throughout the globe which can result damage away from the site of impact.
Intraocular Foreign Body:
Of the 11 patients who had intraocular foreign bodies (Type C injuries), the foreign body was found in the anterior segment in 11(100%) cases. In total, 3 (27.27%) of the foreign bodies were metal, 3 (27.27%) were stone, 3 (27.27%) were wood, 2(18.18%) were broomstick .All the metal foreign bodies extracted from the anterior segment were removed without a magnet. We did not have any case of endophthalmitis in the type C group.
In our case series we found that 7 (63.6%) of the injuries with an intraocular foreign body (type C) resulted in a visual acuity of 6/18 or better. Brinton et al (1982) found that eyes with intraocular foreign bodies had a better prognosis than the others.31Pieramici et al (2003) showed that type C injuries (injuries with an intraocular foreign body) are only 1.31 times more likely to result in a worse outcome when compared to type B injuries. A variety of surgical advances have lead to an improved capability for managing most foreign bodies so that eyes
140 with intraocular foreign bodies seem to have a good prognosis.12 Further analysis of intraocular foreign bodies was impaired by the small study population.
Zone of Injury:
Evidence shows that posterior injuries generally carry a graver prognosis when compared to more anterior injuries.12,31,30 Like the case series described by Mukherjee et al51, our series was predominated by isolated corneal injuries (Zone I injury). In our series, 14 (82.3%) of „Zone
I‟ injuries achieved a final visual acuity of 6/18 or better while 6 (54.4%) of those with Zone II and 1 (10%) of those with Zone III injuries. In the case series described by Pieramici et al
(2003), a follow-up acuity of 20/40 was achieved in 62% of those with Zone I injuries while
39% of Zone II and 25% of Zone III injuries achieved the same.13
Figure 39: Bar chart showing the outcome of the different zones of injury
141
On further analysis, the zone of injury was found to be statistically very significant in Grouped
The p-value is .002513. This result is significant at p < .05 .Ungrouped the p-value is .001271.
The result is significant at p < .05. when associated with visual outcome. This meant that Zone I injuries fare better Zone II which fare better than Zone III, in that order of progression.
However, due to a small study population and sparse cell counts we had to group the variables for accurate analysis.
Associated Ocular Factors:
Retinal Detachment:
In our series, retinal detachment was found in 4 (10.52%). The status of the retina could not be preoperatively assessed in 8 (21.05%) due to media opacities. On follow-up analysis, we found that 73.0% of those detected to have an attached retina had a good visual outcome. It was found that the association between the detection of a preoperatively attached retina and a final vision of at least 6/18 was statistically significant .The p-value is .001151. This result is significant at p < .05.
Evidence shows that the presence of retinal detachment is associated with a poor prognosis.11In a study of traumatic retinal detachments Matthews et al (1998) found that post- traumatic retinal detachments were complicated by proliferative vitreoretinopathy, persistent retinal detachment, macular scar and optic atrophy, and these resulted in significant post- operative morbidity.53
Endophthalmitis: The presence of endophthalmitis is associated with a poor prognosis.11None of the cases in our series presented with an endophthalmitis. Sobaci et al (2000) found
142 endophthalmitis in 8.3% of those with open globe injuries.45 Thompson et al (1995) found that endophthalmitis occurred in 6.3% of the cases studied.54
Length of Laceration:
In general, open globe injuries that are associated with a wound length more than 10mm are associated with a poorer outcome.15,30,31,43 In our series, the mean total length of the globe laceration (including both cornea and sclera) was 8.55mm (median: 7mm; range from ). We found that 21 ( 65.6%) of those injuries with a wound measuring 10mm or less were associated with a final visual acuity of 6/18 or better. All the injuries measuring more than 10mm were associated with a final visual acuity of worse than 6/18. In concordance with the existing literature, we found this association to be statistically significant at p < .05.
Vitreous Haemorrhage:
Many studies have recognised the clinical significance of a vitreous haemorrhage, and it has been identified as a significant prognostic factor in open-globe injuries.57,30,42 However, the diagnosis of vitreous haemorrhage in a penetrating ocular injury often requires ancillary testing with B-mode ultrasonography.52 We did not perform a B-mode ultrasound on patients with an open-globe injury, with the exception of those in which we suspect the presence of a radiolucent intraocular foreign body. We agree with Pieramici et al (1997) in that B-mode ultrasonography may be inappropriate or not available during the initial assessment of the injuries.18
Hyphaema:
The presence of hyphaema was found to signify a poor prognosis in the case series by
Barr et al.42 In our case series, we found that 21 (60%) of those with a hyphaema of less than
143
50% achieved a final visual acuity of 6/18 or better. However, this was found to be statistically insignificant P is 0.080607. The result is not significant at p < .05.
Lenticular Involvement:
The involvement of the crystalline lens has been identified as a poor prognostic factor in numerous studies.57,30,42,54 We found that the lens was detected to be opaque at presentation in 17 patients (44.73%), subluxated in 2 patients (5.2%) and dislocated in 1 patient (2.6%). Pieramici et al (1997) considered this factor to be of limited importance because of the difficulty in confirming the extent and nature of lenticular involvement in open globe injuries.1
Surgical Factors
Lag period between injury and surgery:
A retrospective study by Khatry et al (2004) found that a delay in seeking medical attention was associated with a worse visual outcome.59 Essex et al (2004) also found that a delayed primary repair was associated with the development of post-traumatic endophthalmitis.72 We analysed the outcome of those injuries that were operated within a 24 hours period and outside the 24 hours period. . The result is significant at p < .05.
We need a larger study population to establish the true significance of the time factor.
Requirement for a Second Surgery:
The requirement of a second surgery was found to be associated with a poor visual outcome in previous studies.63,64 In our case series, the requirement for a second surgery was
144 statistically insignificant in predicting the visual outcome The p-value is .240109. This result is not significant at p < .05
Ocular Trauma Score (OTS)
The ocular trauma score was developed by Kuhn et al (2002) to help in grading the severity of an injury and to provide information on the predicted outcome of a given injury. The score was designed for its use during initial clinical examination or surgery. The method of calculation has been discussed in detail in the previous section. The main factors that make up the score are grade of injury (initial visual acuity), type of injury (perforating or globe rupture), afferent pupillary defect, retinal detachment and endophthalmitis. The first three factors are those used in classifying an open globe injury. With regard to the latter factors, Pieramici et al
(1997) recognized that retinal detachments often occur weeks to months after trauma, and is very rarely due to the injury itself.18Also, we often find that endophthalmitis is a delayed complication of trauma.72 The delay in detection of these two factors makes the Ocular Trauma
Score more reliable in the post-operative period.
In the international classification of open globe injuries, the four variable chosen for assessment were such that the description of a combination of these will adequately describe the nature and extent of injury.18 While designing the classification, the Ocular Trauma
Classification Group chose those factors that are of prognostic importance as well as easy to evaluate at presentation. Hence, clubbing the factors together in a score for use in the assessment of the prognosis of an injury was considered.
Pre-Operative Scoring of an Open Globe Injury
145
Each factor associated with the ISOT classification of open globe injuries was put together in the format of a score. The variable of each factor was assigned a score (0 or 1) and the sum of these were calculate. (See Table 21) For example, a patient with a grade 2, type A, zone I, pupil negative injury would be given a score of 0 + 1 + 0 + 0 = 1. The total score was then compared with the final visual outcome and its correlation was analysed.
SCORE
FACTOR 0 1
GRADE 1 TO 3 4 OR 5
TYPE B AND C (SHARP INJURY) A (BLUNT INJURY)
ZONE 1 (ISOLATED TO CORNEA) 11 AND 111 SCLERAL
PUPIL NEGATIVE POSITIVE
Table 30: Scoring system based on the ISOT classification of open-globe injuries.
The maximum score that was possible was 4 and the minimum score that was possible was 0. It was found that 9 (81.8%) cases with a score of 0 achieved a final visual acuity of 6/18 or better and 2(18.18%) cases , 8 (88.8%) cases with score of 1 achieved a final visual acuity of
6/18 or better. 2 (40%) cases out of 5 cases with score of 2 achieved final visual acuity of 6/18 or better. 5(71.4%) cases out of 7 with score of 3 attained a final visual acuity of worse than 6/18,
146 and all those 6 (100.0%) with a score of 4 attained a final visual acuity of worse than 6/18. The scoring system with all four factors was analysed score 0,1,2 vs 3,4 due to sparse count and found to be very significant (p < 0.05) in predicting the visual outcome.
Preoperative predicition of final visual outcome by Ocular Trauma Score
The findings in patients with OTS grades 1 and 2 were studied in detail to estimate the risk and prognostic factors. According to Kuhn et al, OTS grades 1 and 2 are associated with poor functional outcome. Most of the studies of ocular trauma consider the initial and final visual acuity of all patients for assessing the functional outcome, without paying any heed to different categories as per OTS. In the present study, visual acuity improved at regular time intervals compared to visual acuity at initial presentation. The visual acuity at presentation was strongly correlated with final visual outcome at 6 months. Thus, a better visual acuity at presentation will correspond to a better final visual acuity at 6 months, and vice-versa. In all patients of ocular trauma, a strong correlation was found between the initial visual acuity and final visual acuity.
As per WHO criteria, all the patients with OTS category 1 had blindness at 6 months, with no light perception in 100% of OTS 1 patients.
In patients of OTS category 2, blindness at 6 months was present in 22.2% patients.
In patients of OTS category 3 ,moderate to severe visual impairment at 6 months was present in
88.8%.
In patients with OTS category 4 , moderate to severe visual impairment at 6 months was present in 63.63%.
147
In patients with OTS category 5, all patients 100% had mild or no visual impairment.
OTS takes into consideration endophthalmitis, RAPD, retinal detachment, rupture of globe and perforating injury as prognostic variables of the final visual outcome. In our study no cases of endophthalmitis, and perforating injury .
RAPD, retinal detachment , and globe rupture were present in patients of OTS 1 and 2 and 3 grades, resulted always in worst visual outcome. The presence of rupture of globe was found to be associated with the worst final visual outcome. Thus, these variables can be used to predict the final visual outcome in patients with OTS grades 1 and 2 and grade 3 . These findings are similar to the findings by Kuhn et al, who formulated the OTS based on these variables.
The OTS could predict approximate prediction of no light perception among the patients of OTS 1 comparable to that in our study (74% vs 100%).
Recommendations
Variables stated in OTS should be used to predict the final visual outcome in patients open globe ocular injuries .Younger adults, specially males, should be made aware of risk of ocular trauma and should be educated about precautionary measures to prevent it.
Ophthalmologist should use the variables stated in the OTS to predict the final visual outcome in patients with OTS scores and grade. Though all patients with grade 1 OTS will be blind, treatment should not be denied.
148
Limitations of the Study
The ideal statistical analysis for determining the value of a factor in predicting the visual outcome would have been a multivariate analysis, which can accurately determine the importance of each factor in causing a poor outcome. This analysis could not be carried out as our study was prospective in nature and hence had a small sample size and with a large number of factors studied.
A small study population has also resulted in a limitation of the spectrum of injuries assessed by us. For example, we have no cases of type D or type E injuries in this case series. Hence, describing the value of the type of injury as a prognostic factor will not be comprehensive.
A wealth of data should be collected over an extended period of time by continuing the study in order to overcome its present limitations.
149
SUMMARY AND CONCLUSION
CONCLUSION
With the advent of a better understanding of the pathology of ocular trauma and advanced surgical techniques, the prognosis of an open globe injury is improving. Standardisation of the terminology and a consensus for a system of classification of these injuries was accomplished only recently. Our study has prospectively evaluated some of the important prognostic factors of open globe injuries. In general, we found that factors describing the functional status of the eye were more important in predicting the final outcome when compared to those related to the anatomy of the injury.
In the study of the prognostic significance of the factors used to classify an open-globe injury, we found that a good initial visual acuity and the absence of a relative afferent pupillary defect could accurately predict a good visual outcome. The zone of injury was also found to be a significant factor in predicting the visual outcome, with more posterior injuries having poorer prognoses. Our data was inadequate to evaluate the prognostic significance of the type of injury as defined by the international society of ocular trauma classification. However, open globe injuries caused by blunt trauma carry a poorer prognosis when compared to those caused by a sharp object.
Independently, we found that a wound measuring less than 10mm and the absence of a retinal detachment were significant predictors of a good visual outcome. Our data also suggested an interval of less than 24 hours between injury and surgery lead to a favourable outcome.
However, a larger number of injuries would need to be studied to establish its statistical significance.
150
The Ocular Trauma Score is considered to be a valuable tool in establishing the severity of an open-globe injury. However, as the presence of endophthalmitis and retinal detachment are delayed complications of trauma, the value of the score in pre-operative evaluation of an open globe injury is uncertain. We have established a sensitive pre-operative scoring system based on the internationally accepted factors used to classify an open-globe injury. When tested on our data, the scoring system could accurately predict the outcome.
151
SUMMARY
A standard language to share eye injury information has been developed by Kuhn and associate in 1996 and adopted by the International Society of Ocular Trauma in 1997.11This made classification of eye injuries less ambiguous, and has set the stage for prospective clinical studies. Many anatomical and pathological factors that carry either a good or poor prognosis have been studied in numerous retrospective studies in the past. We prospectively evaluated all patients with open globe injuries presenting to Karnataka institute of medical sciences Hospital between January 2016 to December 2016 over 1 year period and studied a list of factors with respect to the final visual outcome. Some factors which had a statistically significant association with the final visual acuity were subjected to a scoring system to determine their collective importance in determining the visual outcome.
We found that the factors that were statistically significant prognosticators of the final visual outcome were grade of injury, afferent pupillary response, zone of injury, retinal detachment and wound length. Although the time interval of less than 24 hours between injury and surgery was associated with a better visual outcome, the association was found to be statistically significant. We also established a pre-operative scoring system based on the internationally accepted factors used to classify an open-globe injury, which could accurately predict a favourable outcome.
152
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160
INFORMED CONSENT FORM
“A PROSPECTIVE STUDY OF VISUAL OUTCOME OF OPEN GLOBE
OCULAR INJURIES AT KIMS HUBLI”
Subject identification number for this study ______
I have received the information sheet on the above study and have read and / or understood the
Written information. I have been given the chance to discuss the study and ask questions.
I consent to take part in the study and I am aware that my participation is voluntary.
I understand that I may withdraw at any time without this affecting my future care. I understand that the information collected about me from my participation in this study and sections of any of my medical notes may be looked at by responsible persons (ethics committee members / regu latory authorities). I give access to these individuals to have access to my records. I understand
I will receive a copy of the patient information sheet and the informed consent form
Signature / Thumb Impression of subject Signature / Thumb Impression of legally
Date of signature accepted representative
Name of the subject Date of signature
Name of the representative Ifu\RNATAIiT INSTITUTE OF MEDICAL SCIENCES HUBBALLI - 580021
Ref No.
To, The Registraro RGUHS, Jayanagarr 4th block, Bangalore-56001 I
Respected Sir, Subject: Departmental Ethical clearance.
With regards to the subject mentioned above, the dissertation subject titled ,iA pRoSpECTIvE STuDY OF vISUAL oUTCOME oF OPEN GLOBE OCULAR INJIruES AT KIMS HUBLI" is justifiable and has taken ethical clearance from the department.
Thanking you.
Yours sincerely, f---' E *- :,,;j-"#;;i t,*f#'** :wS'"-m-rfu " PROFESSoR AND _*X#; "' SUODIi * -#..:5 DEPARTMENT OF OPHTHALMOLOGY K[MS, HUBBALLI.
Date: {41t,;2orf Place: Hubballi KARI{ATAXJT INSTITUTE OF MEDICAL SCIENCES HUBBALLI - 580021
Ref No.
To, The Registrar, RGIIHS, Jayanagar,4th block, Bangalore-560011
Respected Sir,
Subject: Institutional Ethical clearance.
With regards to the subject mentioned above, the dissertation subject titled I'A PROSPECTIVE STUDY OF VISUAL OUTCOME OF OPEN GLOBE OCULAR INJIIRIES AT KIMS HUBLI" is justifiable and has taken ethical clearance from the institution.
Thanking you.
Yours sincerely,.,_.,'ffii';;ti;:i' r.in.ip#Effi' Wu{$:ur"
Date: Q-.?/, t lao,t Place: Hubballi STUDY PERFORMA FORMAT
“A PROSPECTIVE STUDY OF VISUAL OUTCOME OF OPEN GLOBE
OCULAR INJURIES AT KIMS HUBLI”
Name: Age:
Sex : Male / Female Op No : Ip No:
Address:
Contact No: Urban / Rural Education:
History Of Injury:
Date : Time: Am/Pm
Location: Road Traffic Accidents / Industrial / Farm / Agricultural / Home / School /
College / Recretion / Sport / Street / Highway / Public Building / Unknown / Others.
Intent : Unintentional / Assault / Self Inflicted / Unknown.
Work Related: Yes / No / Unknown.
Alcohol Abuse: Yes / No / Unknown.
Eye Protection : 1)Available / Used / Not Used / Unknown.
2) Not Available.
Source Of Injury:
Any Other Injuries: (Not To The Eye).
161
Description Of Injured Eye:
Eye Being Described: Right Eye Prior To Injury
:Normal/Abnormal
Left Abnormal( ).
Nature Of Injury:
Visual Acuity : Injured Eye Date:
Patient Co-Operation : Good / Average / Poor.
R A P D : Absent / Present.
Zone : Zone 1. Isolated To Cornea (Including The Limbus ).
Zone 2. Corneosclearl Limbus To A Point 5mm Posterior To Limbus
Zone 3. Posterior To The Anterior 5mm To Sclera.
Type : / Penetrating / Perforating / Rupture / IOFB.
Tissue Involved:
Periorbital Area:
Lacrimal Apparatus:
Lids :
Conjunctiva:
Cornea: Total Wound Length:
162
Sclera:
Anterior Chamber: Hypeaema:
Iris :
Pupil:
Lens:
Vitreous:
Retina : Attached / Detached / Not Visible.
Macula:
I O F B :
Extra Occular Movements: Normal / Restricted
Others;
B-Scan :
X-Ray:
Ct/Mri: 163
Initial Repair /Procedure:
Surgery:
Surgeon: Date And Time:
Secondary Repair /Procedure: Date And Time:
Follow Up Visual Acuity :
Comments :
Guide : Dr Uday Sridar Mulgund .
Signature:
Head Of The Department : Dr Y B Bhajanthi.
Signature:
164
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Figure 10: Granite foreign body in a stone cutting mason
165
Figure 27 : Zone 1 injury
Figure 28 : Lens Disruption.
166
Figure 29 : Zone 1 injury with iris prolapsed.
Figure 30 : Zone I injury: Siedel’s Test – Positive
167
Figure 31 : Globe Rupture with Phacocoele
Figure 32: Zone 2 injury with iris prolapsed
168
Figure 33 : Zone 3 injury
Figure 34 : Traumatic cataract
169
Figure 35 : Subluxation of lens
170