Ocular Motility

Total Page:16

File Type:pdf, Size:1020Kb

Ocular Motility 10 Ocular Motility C. Denise Pensyl, William J. Benjamin linicians are faced with the challenge of differenti­ approximately 2 rnm, below which the effects of Cating the etiologies of asthenopia, blur, diplopia, reduced retinal illuminance and diffraction outweigh and headaches associated with the use of the eyes by the beneficial aspects ofan increase in depth offield and their patients. Oculomotor deficiencies can be one of reduction of ocular spherical aberration. The entrance several possible causes of such symptoms and are the pupil also controls blur circle size at the retina for object result of defects in the central nervous system, afferent rays not originating from the far point plane of the eye. or efferent nerve pathways, or local conditions of a The entrance pupil averages 3.5 mm in diameter in nature so as to impede appropriate oculomotor func­ adults under normal illumination but can range from tion. Oculomotor function will be extensively analyzed 1.3 mm to 10 mm. It is usually centered on the optic during phorometry (see Chapter 21) in terms of binoc­ axis of the eye but is displaced temporally away from ularity and muscle balance after the subjective refraction the visual axis or line of sight an average of 5 degrees. has been completed. This chapter focuses on clinical The entrance pupil is decentered approximately procedures that are typically used to analyze oculomo­ 0.15 mm nasally and 0.1 mm inferior to the geometric tor function before the subjective refraction is per­ center ofthe cornea. J This amount ofdecentration is not formed, though in some cases the practitioner may distinguished in casual observation or by the clinician's decide to use a few of these tests after the refraction is normal examination ofthe pupils. In general, the diam­ determined. eter of the pupil gradually becomes smaller after about By using primarily handheld devices or instruments, the age of 12 to 18 years. This appears to be a linear the normality or abnormality of the functions of the relationship in which pupil size for light-adapted and ocular muscles are estimated: the iris sphincter and dark-adapted eyes at age 20 (means nearly 5 mm and dilator muscles, the eyelid muscles involved in mainte­ 8 mrn, respectively) both diminish to about 2 mm and nance ofthe palpebral aperture, the extraocular muscles, 2.5 mrn, respectively, at age 802.3 (see Figure 25-4). The and the ciliary muscles. Hence, ocular motility is progressive change in size is known as senile miosis and assessed by observation of (1) the pupils and pupillary is shown in Table 10-1. It is not totally explained by reflexes, (2) the palpebral apertures and eyelid move­ increased iris rigidity or loss of muscle fibers in the iris, ments, (3) monocular and binocular eye movements, but apparently also includes a progressive delayed (4) monocular and binocular eye alignment, and (5) latency of response time, indicating some neurological accommodative amplitudes and facility. involvement. 2 Aging is presumed to cause a reduction in sympathetic tone." Because it is only the entrance pupil that can be examined noninvasively by the prac­ THE PUPILS AND PUPILLARY titioner, in clinical parlance the word "entrance" is REFLEXES dropped from the term and the single word "pupil" is meant to apply to that which is observed, which is the The pupil controls retinal illumination and determines entrance pupil. retinal image quality. The entrance pupil of the eye is Pupil size is always changing in the normal eye formed by refraction of the real pupil by the cornea and because of convergence/accommodation (near or triad is just over 3 mm behind the anterior corneal surface. response), pupillary responses to light and small, Retinal illumination is proportional to the square ofthe regular oscillations from fluctuations in the sympathetic pupillary diameter. Depths of field and focus for clear and parasympathetic nervous systems. Pupil size can be vision are inversely proportional to pupil diameter. The influenced by drugs and medications (see Chapter 12) lower limit of pupil size for optimal visual acuity is and is slightly larger in persons with light irises 356 Ocular Motility Chapter 10 357 Pupil size is controlled by smooth muscles inner­ TABLE 10-1 Approximate Pupil Diameters vated by the autonomic nervous system. An effective According to Age competition between the radial dilator muscle, which is sympathetically innervated and acts to dilate the pupil, Photopic Scotopic and the annular sphincter muscle, which is parasympa­ Age (years) Diameter [mm] Diameter (mm) thetically innervated and acts to constrict the pupil, 20 5.0 8.0 determines the pupil size. The parasympathetic inner­ 40 4.0 6.0 vation has more control over the pupil size, because the 50 3.5 5.5 sphincter muscle is the stronger of the two. The dilator 60 3+ 4.25 muscle acts in opposition such that mydriasis occurs 70 2.5 3.0 when the sphincter tone is released. As a result, con­ 80 2+ 2.5 striction of the pupil to light (miosis) is slightly faster than dilation (mydriasis) when the light is extinguished. The unstable equilibrium reached between the sphinc­ ter and dilator muscles creates small continuous varia­ compared with dark irises. Pupils become mydriatic in tions in the pupil size, which are normal and called response to large sensory, emotional, or psychological pupillary unrest or hippus," The normal function of the stimuli. Hyperthyroidism and ingestion of lead can pupil and its innervation are extensively covered in produce mydriasis. Various medications, including anti­ Chapter 4, and pharmacological manipulation of the histamines, over-the-counter decongestants, anticholin­ pupil is covered in Chapter 12. The reflexes controlling ergics, phenothiazines, amphetamines, cocaine, and pupil size are important in the diagnosis of neuro­ antianxiety agents, may also enlarge the pupils.v" The ophthalmic conditions. pupils become miotic in response to pain or irritation The principal sensor for the pupillary light response within the globe as a result of the oculopupillary reflex is the photopic system (the cones); therefore, illumina­ during keratitis, iritis, or trauma." However, pain else­ tion of the fovea is the primary determinant of the where in the body tends to cause pupil dilation. Long­ pupillary light reflex. The retinal nerve fibers that relay standing diabetes, sleep, and intraocular inflammation information for pupillary control travel through the produce miosis. The pupils ofinfants and the elderly are optic nerve to the optic chiasm. Here, approximately small." Medications, including cholinergic agents used half of the afferent (sensory) fibers decussate to the to treat glaucoma, chlorpromazine, cholinesterase contralateral optic tract, and the remaining half con­ inhibitors (found in insecticides and toxic nerve gases), tinue in the ipsilateral tract. The afferent fibers follow and morphine derivatives, constrict the pupil.t" Under the brachium ofthe respective superior colliculus to the ordinary circumstances, the pupils of females may be midbrain, where they synapse with a pretectal nucleus larger than those of males, and the pupils of myopes in the hypothalamus. Here, the fibers undergo semide­ larger than those ofhyperopes. However, the pupil sizes cussation. Each ofthe pretectal nuclei sends crossed and of females and males are no different, and of myopes uncrossed intercalated neurons through the posterior and hyperopes no different, when specialized condi­ commissure to the Edinger-Westphal nucleus, the tions ensure that accommodative differences have been origin of the efferent (motor) fibers that control pupil accounted for." size." Therefore, the photopic information given to one The pupils should appear round, roughly centered eye is normally transmitted to both pupils, creating within the iris, and of equal size in the normal patient. direct and consensual (indirect) responses. Both of The irises should be of the same coloration. The clini­ these responses, the direct pupillary light reflex and the cian should be aware of deviations from this norm, consensual pupillary light reflex, should be evaluated which could appear in the form of a unilateral or bilat­ when the pupillary responses are examined. eral irregular pupil (a nonround pupil), ectopic pupil The parasympathetic innervation to the iris, starting (significantly decentered pupil), polycoria (more than in the Edinger-Westphal nucleus, travels with the third one pupil in an eye), anisocoria (pupils ofdifferent sizes cranial nerve, emerging from the brain ventrally between in the two eyes), or heterochromia (irises of different the cerebral peduncles. The nerve then follows a course color or lightness/darkness in the two eyes). In ocular along the posterior communicating arteries to pierce the albinism and oculocutaneous albinism, the irises of the wall of the cavernous sinus. Here it is close to the first two eyes appear to contain little or no color and scat­ and second divisions ofthe fifth nerve. The nerve enters tered light enters the eye through the iris, such that the the orbit via the superior orbital fissure. The pregan­ pupil is not allowed to perform its optical functions. glionic parasympathetic fibers deviate from the third In aniridia, the iris is absent or only partially present; cranial nerve and synapse at the ciliary ganglion. therefore, the pupil does not exist or is considered to be Postganglionic fibers reach the iris sphincter muscle via expanded to the ciliary body. the short ciliary nerves.' The overwhelming majority of 358 BENJAMIN Borishs Clinical Refraction these parasympathetic fibers innervate the ciliary muscle mination are made, is an ideal time to make the assess­ for control of accommodation, whereas only 3% of the ment. The room should be illuminated well enough to fibers innervate the iris sphincter muscle. II clearly see the pupils, but light should not be beamed The iris dilator muscle receives innervation from the directly at the eyes. The patient is asked to fixate a dis­ sympathetic system, which begins in the posterior hypo­ tance target, and the diameter of each pupil is measured thalamus.
Recommended publications
  • Vision Screening Training
    Vision Screening Training Child Health and Disability Prevention (CHDP) Program State of California CMS/CHDP Department of Health Care Services Revised 7/8/2013 Acknowledgements Vision Screening Training Workgroup – comprising Health Educators, Public Health Nurses, and CHDP Medical Consultants Dr. Selim Koseoglu, Pediatric Ophthalmologist Local CHDP Staff 2 Objectives By the end of the training, participants will be able to: Understand the basic anatomy of the eye and the pathway of vision Understand the importance of vision screening Recognize common vision disorders in children Identify the steps of vision screening Describe and implement the CHDP guidelines for referral and follow-up Properly document on the PM 160 vision screening results, referrals and follow-up 3 IMPORTANCE OF VISION SCREENING 4 Why Screen for Vision? Early diagnosis of: ◦ Refractive Errors (Nearsightedness, Farsightedness) ◦ Amblyopia (“lazy eye”) ◦ Strabismus (“crossed eyes”) Early intervention is the key to successful treatment 5 Why Screen for Vision? Vision problems often go undetected because: Young children may not realize they cannot see properly Many eye problems do not cause pain, therefore a child may not complain of discomfort Many eye problems may not be obvious, especially among young children The screening procedure may have been improperly performed 6 Screening vs. Diagnosis Screening Diagnosis 1. Identifies children at 1. Identifies the child’s risk for certain eye eye condition conditions or in need 2. Allows the eye of a professional
    [Show full text]
  • Strabismus, Amblyopia & Leukocoria
    Strabismus, Amblyopia & Leukocoria [ Color index: Important | Notes: F1, F2 | Extra ] EDITING FILE ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Objectives: ➢ Not given. Done by: Jwaher Alharbi, Farrah Mendoza. ​ ​ Revised by: Rawan Aldhuwayhi ​ Resources: Slides + Notes + 434 team. ​ ​ NOTE: F1& F2 doctors are different, the doctor who gave F2 said she is in the exam committee so focus on her notes Amblyopia ● Definition Decrease in visual acuity of one eye without the presence of an organic cause that explains that decrease ​ ​ in visual acuity. He never complaints of anything and his family never noticed any abnormalities ​ ● Incidence The most common cause of visual loss under 20 years of life (2-4% of the general population) ● How? Cortical ignorance of one eye. This will end up having a lazy eye ​ ● binocular vision It is achieved by the use of the two eyes together so that separate and slightly dissimilar images arising in each eye are appreciated as a single image by the process of fusion. It’s importance 1. Stereopsis 2. Larger field If there is no coordination between the two eyes the person will have double vision and confusion so as a compensatory mechanism for double vision the brain will cause suppression. The visual pathway is a plastic system that continues to develop during childhood until around 6-9 years of age. During this time, the wiring between the retina and visual cortex is still developing. Any visual problem during this critical period, such as a refractive error or strabismus can mess up this developmental wiring, resulting in permanent visual loss that can't be fixed by any corrective means when they are older Why fusion may fail ? 1.
    [Show full text]
  • Genes in Eyecare Geneseyedoc 3 W.M
    Genes in Eyecare geneseyedoc 3 W.M. Lyle and T.D. Williams 15 Mar 04 This information has been gathered from several sources; however, the principal source is V. A. McKusick’s Mendelian Inheritance in Man on CD-ROM. Baltimore, Johns Hopkins University Press, 1998. Other sources include McKusick’s, Mendelian Inheritance in Man. Catalogs of Human Genes and Genetic Disorders. Baltimore. Johns Hopkins University Press 1998 (12th edition). http://www.ncbi.nlm.nih.gov/Omim See also S.P.Daiger, L.S. Sullivan, and B.J.F. Rossiter Ret Net http://www.sph.uth.tmc.edu/Retnet disease.htm/. Also E.I. Traboulsi’s, Genetic Diseases of the Eye, New York, Oxford University Press, 1998. And Genetics in Primary Eyecare and Clinical Medicine by M.R. Seashore and R.S.Wappner, Appleton and Lange 1996. M. Ridley’s book Genome published in 2000 by Perennial provides additional information. Ridley estimates that we have 60,000 to 80,000 genes. See also R.M. Henig’s book The Monk in the Garden: The Lost and Found Genius of Gregor Mendel, published by Houghton Mifflin in 2001 which tells about the Father of Genetics. The 3rd edition of F. H. Roy’s book Ocular Syndromes and Systemic Diseases published by Lippincott Williams & Wilkins in 2002 facilitates differential diagnosis. Additional information is provided in D. Pavan-Langston’s Manual of Ocular Diagnosis and Therapy (5th edition) published by Lippincott Williams & Wilkins in 2002. M.A. Foote wrote Basic Human Genetics for Medical Writers in the AMWA Journal 2002;17:7-17. A compilation such as this might suggest that one gene = one disease.
    [Show full text]
  • Ocular Rotations and the Hirschberg Test
    Pacific University CommonKnowledge College of Optometry Theses, Dissertations and Capstone Projects 3-1-1977 Ocular rotations and the Hirschberg test A John Carter Pacific University Recommended Citation Carter, A John, "Ocular rotations and the Hirschberg test" (1977). College of Optometry. 448. https://commons.pacificu.edu/opt/448 This Thesis is brought to you for free and open access by the Theses, Dissertations and Capstone Projects at CommonKnowledge. It has been accepted for inclusion in College of Optometry by an authorized administrator of CommonKnowledge. For more information, please contact [email protected]. Ocular rotations and the Hirschberg test Abstract The Hirschberg test is an objective means of determining the angle of strabismus by noting the distance the corneal reflex of a light source is from the center of the entrance pupil. A scale factor is used in converting the amount the reflex distance is in millimeters ot prism diopters. Recent studies have demonstrated this factor to be 22 prism diopters for each millimeter. This study notes how axial length would effect this scale factor. Using ultrasound axial lengths of thirty eyes were measured and compared to the results of a Hirschberg simulation. A small effect results from this comparison. The mean values of scale factor determination noted twenty-three prism diopters per millimeter. Degree Type Thesis Degree Name Master of Science in Vision Science Committee Chair Niles Roth Subject Categories Optometry This thesis is available at CommonKnowledge: https://commons.pacificu.edu/opt/448 Copyright and terms of use If you have downloaded this document directly from the web or from CommonKnowledge, see the “Rights” section on the previous page for the terms of use.
    [Show full text]
  • Prevalence of Amblyopia in Congenital Blepharoptosis: a Systematic Review and Meta-Analysis
    Int J Ophthalmol, Vol. 12, No. 7, Jul.18, 2019 www.ijo.cn Tel: 8629-82245172 8629-82210956 Email: [email protected] ·Meta-Analysis· Prevalence of amblyopia in congenital blepharoptosis: a systematic review and Meta-analysis Jia-Ying Zhang1,2, Xiao-Wei Zhu1,2, Xia Ding1,2, Ming Lin1,2, Jin Li1,2 1Department of Ophthalmology, Shanghai Ninth People’s and management of amblyopia should be integral to the Hospital, Shanghai Jiao Tong University School of Medicine, treatment of congenital ptosis. Shanghai 200011, China ● KEYWORDS: amblyopia; congenital ptosis; blepharophimosis; 2Shanghai Key Laboratory of Orbital Diseases and Ocular systematic review Oncology, Shanghai 200011, China DOI:10.18240/ijo.2019.07.21 Correspondence to: Jin Li. Department of Ophthalmology, Shanghai Ninth Peolple’s Hospital, Shanghai Jiao Tong Citation: Zhang JY, Zhu XW, Ding X, Lin M, Li J. Prevalence of University School of Medicine, No.639, Zhizaoju Road, amblyopia in congenital blepharoptosis: a systematic review and Shanghai 200011, China. [email protected] Meta-analysis. Int J Ophthalmol 2019;12(7):1187-1193 Received: 2018-09-25 Accepted: 2019-03-05 INTRODUCTION Abstract ongenital blepharoptosis is an eyelid disorder that ● AIM: To conduct a systematic review and Meta-analysis of C is characterized by an involuntary drooping of the the published literature to evaluate the pooled prevalence upper eyelid since birth. Etiologically, myogenic factors are rate of amblyopia in patients with congenital ptosis. most common, referring to dysgenesis or weakness of the ● METHODS: We searched the PubMed, Embase, the levator muscle and sometimes the superior rectus muscle. Cochrane Central Register of Controlled Trials, China The etiological subtypes of congenital ptosis include simple National Knowledge Infrastructure, Wanfang Data, and congenital ptosis, blepharophimosis-ptosis-epicanthus inversus Chongqing VIP databases for studies reporting the syndrome (BPES), Marcus Gunn jaw-winking syndrome prevalence of amblyopia in patients with congenital ptosis.
    [Show full text]
  • The Paediatric Ophthalmic Examination Examination of a Child’S Eye Can Be Challenging and Traumatic but Could Save the Child’S Sight Or Even His Life
    The paediatric ophthalmic examination Examination of a child’s eye can be challenging and traumatic but could save the child’s sight or even his life. A du Bruyn,1 MB ChB, Dip (Ophth), FC (Ophth); D Parbhoo,2 MB ChB, FC (Ophth) 1Consultant Ophthalmologist, St Aidan’s Hospital, University of KwaZulu-Natal, Durban, South Africa 2Consultant Ophthalmologist, Parklands Hospital and Inkosi Albert Luthuli Central Hospital, University of KwaZulu-Natal, Durban, South Africa Correspondence to: A du Bruyn ([email protected]) Twenty-ve thousand children in South • proptosis • 1 - 2 years: A child should be able to Africa are blind, mainly because of • ptosis pick up hundreds and thousands with congenital cataracts, congenital glaucoma, • epiphora ease (dierent size sweets can be used). malignant tumours (retinoblastoma), • buphthalmos or microphthalmos Teller’s and Cardi acuity cards can be retinopathy of prematurity, inammation • red eyes used. and injuries. Strabismus, amblyopia and • cloudy cornea • 2 - 3 years: At this age they can name refractive errors cause many more children • pupil abnormalities pictures and any of the picture charts to have reduced vision. Unfortunately, half • leucocoria. can be used (Kay pictures, Allen’s picture of these children who go blind will die cards, Bailey-Hall). Hundreds and within 2 years, mainly due to accidents. Visual assessment thousands may still be useful. Visual milestones • 3 - 5 years: Matching optotypes (use Fiy per cent of childhood blindness can be A child’s vision is developing and to establish the illiterate E chart, Landolt’s C test, prevented by early detection and treatment, visual acuity in a child is challenging for Sheridan- Gardener’s test, Lea charts).
    [Show full text]
  • PG Series Ophthalmology Buster
    PG Series Ophthalmology Buster PG Series Ophthalmology Buster E Ahmed Formerly Head, Department of Ophthalmology Calcutta National Medical College Consultant, Eye Care and Research Centre Kolkata JAYPEE BROTHERS MEDICAL PUBLISHERS (P) LTD New Delhi Published by Jitendar P Vij Jaypee Brothers Medical Publishers (P) Ltd B-3, EMCA House, 23/23B Ansari Road, Daryaganj New Delhi 110 002, India Phones: +91-11-23272143, +91-11-23272703, +91-11-23282021, +91-11-23245672, Rel: 32558559 Fax: +91-11-23276490, +91-11-23245683 e-mail: [email protected] Visit our website: www.jaypeebrothers.com Branches • 2/B, Akruti Society, Jodhpur Gam Road Satellite, Ahmedabad 380 015 Phones: +91-079-26926233, Rel: +91-079-32988717, Fax: +91-079-26927094 e-mail: [email protected] • 202 Batavia Chambers, 8 Kumara Krupa Road, Kumara Park East, Bangalore 560 001 Phones: +91-80-22285971, +91-80-22382956, Rel: +91-80-32714073, Fax: +91-80-22281761 e-mail: [email protected] • 282 IIIrd Floor, Khaleel Shirazi Estate, Fountain Plaza, Pantheon Road, Chennai 600 008 Phones: +91-44-28193265, +91-44-28194897, Rel: +91-44-32972089 Fax: +91-44-28193231 e-mail: [email protected] • 4-2-1067/1-3, 1st Floor, Balaji Building, Ramkote Cross Road, Hyderabad 500 095 Phones: +91-40-66610020, +91-40-24758498, Rel:+91-40-32940929 Fax:+91-40-24758499, e-mail: [email protected] • No. 41/3098, B & B1, Kuruvi Building, St. Vincent Road, Kochi 682 018, Kerala Phones: +91-0484-4036109, +91-0484-2395739, +91-0484-2395740 e-mail: [email protected] • 1-A Indian Mirror Street, Wellington Square, Kolkata 700 013 Phones: +91-33-22451926, +91-33-22276404, +91-33-22276415, Rel: +91-33-32901926 Fax: +91-33-22456075, e-mail: [email protected] • 106 Amit Industrial Estate, 61 Dr SS Rao Road, Near MGM Hospital, Parel, Mumbai 400 012 Phones: +91-22-24124863, +91-22-24104532, Rel: +91-22-32926896 Fax: +91-22-24160828, e-mail: [email protected] • “KAMALPUSHPA” 38, Reshimbag, Opp.
    [Show full text]
  • 20-OPHTHALMOLOGY Cataract-Ds Brushfield-Down Synd Christmas
    20-OPHTHALMOLOGY cataract-ds BrushfielD-Down synd christmas tree-myotonic dystrophy coronaRY-pubeRtY cuneiform-cortical(polyopia) cupuliform-post subcapsular(max vision loss) Elschnig pearl, ring of Soemmering-after(post capsule) experimenTal-Tyr def glassworker-infrared radiation grey(soft), yellow, amber, red(cataracta rubra), brown(cataracta brunescence), black(cat nigrans)(GYARBB)-nuclear(hard) heat-ionising radiation Membranous-HallerMan Streiff synd morgagnian-hypermature senile oildrop(revers)-galactossemia(G1PUT def) post cortical/bread crumb/polychromatic lustre/rainbow-complicated post polar-PHPV(persistent hyperplastic prim vitreous) radiational-post subcapsular riders-zonular/lamellar(vitD def, hypoparathy) roseTTe(ant cortex)-Trauma, concussion shield-atopic dermatitis snowstorm/flake-juvenile DM(aldose reductase def, T1>T2, sorbitol accumulat) star-electrocution sunflower/flower of petal-Wilson ds, chalcosis, penetrating trauma syndermatotic-atopic ds total-cong rubella zonular-galactossemia(galactokinase def) stage of cataract lamellar separation incipient/intumescence(freq change of glass) immature mature hypermature Aim4aiims.inmorgagnian sclerotic lens layer ant capsule ant epithelium lens fibre[66%H2O, 34%prot-aLp(Largest), Bet(most aBundant), γ(crystalline, soluble)] nucleus embryonic(0-3mthIUL) fetal(3-8mthIUL)-Y shape(suture) infantile(8mthIUL-puberty) adult(>puberty) cortex post capsule thinnest-post pole>ant pole thickest, most active cell-equator vitA absent in lens vitC tpt in lens by myoinositol H2O tpt in lens
    [Show full text]
  • Change of Eye Position in Patients with Orthophoria and Horizontal Strabismus Under General Anesthesia
    Korean J Ophthalmol Vol. 19:55-61, 2005 Change of Eye Position in Patients with Orthophoria and Horizontal Strabismus under General Anesthesia Hee Chan Ku, MD1, Se-Youp Lee, MD2, Young Chun Lee, MD1 Department of Ophthalmology, Uijongbu St. Mary's Hospital, College of Medicine, The Catholic University of Korea1, Seoul, Korea Department of Ophthalmology, Dongsan Medical Center College of Medicine, Keimyung University of Korea2, Deagu, Korea We studied the relationship between eye position in the awakened state and in the surgical plane of anesthesia in orthophoric and horizontal strabismus patients. We classified 105 orthophoric and horizontal strabismus patients into 5 groups, measured the eye position at the primary position by photographic measurement of the corneal reflex positions and undertook a quantitative study of eye po sitio n. U nder general anesthesia, the mean diverg ence w as 3 9.7± 8 PD fo r the eso tro pia gro up, 36 .6 ±11.7 PD for exophoria, 27.4±8.1 PD for orthophoria, and 11.1±10.2 PD for exotropia I (≤30 PD). Therefore, the esotropia group had the largest amount of divergence among the groups, but the eye position of the exotropia II (>30 PD) group was rather convergent at 11.0±6.5 PD. According to the eye position of the fixating and nonfixating eyes in the esotropia group, both eyes converged with an angle deviation of 14.4±4.8 PD divergent and 14.1±4.8 PD divergent, respectively (P=.71). In the exotropia groups (I, II), the fixating eye diverged but the nonfixating eye rather converged.
    [Show full text]
  • Ocular Trauma Occupational Ocular Trauma
    AOCOPM Midyear Educational Meeting March 8-11, 2018 I. Introduction II. Objectives Epidemiology of Ocular Injuries Michael B. Miller, D.O., O.D., M.P.H. Review of Anatomy Wellstar Occupational Medicine Examination of eye Atlanta, GA Examine eye for trauma and foreign bodies Manage chalazia, styes, corneal abrasions, foreign bodies Ocular Trauma Occupational Ocular Trauma “Epidemiological data on eye injuries In US, 280,000 work-related tx in ED are still rare or totally lacking in large 1999 (Am J Ind Med 2005) parts of the world.” J Clin Ophth Res 2002, BLS est 65,000/year 2016 2009, BLS est. 2.9/10,000 full time 90 % are preventable workers requiring 2 or more days off Prevalence rates vary a great deal (5- NIOSH Work-RISQS query shows 15%) 134,000 in 2015 Approx 50% work-related Non-traumatic ocular illnesses (allergic conjunctivitis) grossly underreported Occupational Ocular Trauma Risk Factors- Ocular Trauma Majority are males BLS est. 60% fail to wear proper eye Most are in age 25-44 protection incl. side/top shields Metalworkers at highest risk Use of tools (unskilled use increases risk 48X) Others: agriculture, construction, manufacturing Performing unusual task (< 1 day/week) Types of injuries: Abrasions, FB/splash, Working overtime (3X inc risk) Conjunctivitis, Burns, Contusion, Distraction, fatigue, Rushed Open/Penetrating wound, Assoc with sleep duration not stat signif F - 1 AOCOPM Midyear Educational Meeting March 8-11, 2018 PPE Effect- Ocular Trauma Anatomy 44% reported eye injury despite PPE (Occ Med, Jan 2009) Reported increase use of PPE during work following eye injury (from median 20% to 100%) (Workplace Health Safety, 2012) Role of provider education in prevention….Yuge! Anatomy of the orbital septum Anatomy of the eye and surrounding structures IV.
    [Show full text]
  • Amblyopia Strabismus
    7 Strabismus, Amblyopia & Leukocoria Color index: 432 Team – Important – 433 Notes – Not important [email protected] Objectives (Weren’t provided) Strabismus Amblyopia Leukocoria Esotropia Pseudostrabismus Exotropia Strabismus Definition: Abnormal alignment of the eyes; the condition of having a squint. (Oxford dictionary) Epidemiology: 2%-3% of children and young adults. Prevalence in males=females Causes: Inherited pattern. Most patients fall under this category, so it is important to ask about family history. Idiopathic. Binocular Single Vision can be: Neurological conditions (Cerebral palsy, Hydrocephalus & -Normal – Binocular Single brain tumors). vision can be classified as Down syndrome. normal when it is bifoveal and Congenital cataract, Eyes Tumor. there is no manifest deviation. -Anomalous - Binocular Single Why we are concerned about strabismus? vision is anomalous when the 1. Double vision. Mainly in adults. because images of the fixatedchildren object and infants have a suppression feature which are projected from the fovea is not found in adults of one eye and an extrafoveal 2. Cosmetic. area of the other eye i.e. when 3. Binocular single vision. the visual direction of the retinal elements has changed. Consequences A small manifest strabismus is therefore always present in Amblyopia (lazy eye). In children anomalous Binocular Single Double vision. Usually in adults but you may vision. see it in children. E.g: if they have a tumor and they present with sudden esotropia and diplopia Tests for deviation: 1. Hirschberg test: 1mm from pupil center=15PD (prism diopter) or 7o. also known as corneal light reflex you shine the light at one arm length into both eyes and see the corneal reflex.
    [Show full text]
  • Frontalis Sling: a Modified Simple Technique
    Br J Ophthalmol: first published as 10.1136/bjo.69.6.443 on 1 June 1985. Downloaded from British Journal of Ophthalmology, 1985, 69, 443-445 Frontalis sling: a modified simple technique S M BETHARIA From Dr Rajendra Prasad Centrefor Ophthalmic Sciences, Ansari Nagar, New Delhi 110029, India SUMMARY A modified simple technique of brow suspension by using 4-0 Supramid (non- absorbable thread) suture and only one skin incision is described in 25 eyes of 15 cases of ptosis, including cases of congenital and mechanical ptosis and ptosis with Marcus Gunn phenomenon. This technique avoids the use of any special instruments such as the Reese ptosis knife and Wright needle. A sling operation is by far the easiest of all ptosis with the Marcus Gunn phenomenon after disinser- operations to perform. Though it may have im- tion of levator muscle from the tarsal plate (Table 1). portant disadvantages, such as the risk of lagophthal- mos and lid lag in down gaze, it is the operation of SURGICAL PROCEDURE choice for certain cases of gross bilateral ptosis with The operation is carried out under general anaes- poor levator function as seen in the blepharophimosis thesia. The first step is to lift the lid with the help of syndrome, cases of mechanical ptosis, and in severe the index finger just medial to the centre of the upper unilateral ptosis covering the pupillary area to pre- lid and observe the contour of the lid margin in vent amblyopia before a definitive levator operation relation to the limbus. This gives an approximate idea can be carried out.
    [Show full text]