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OcularOcular Trauma Trauma Traumatic Retinal

Detachment Monika Kapoor MS

Monika Kapoor MS, Rohan Chawla FRCS (Glasg), Koushik Tripathy MD, Ravi Bypareddy MD, Babulal Kumawat MD, Subodh Kumar Singh MD, Pradeep Venkatesh MD, Rajpal Vohra MD, Yog Raj Sharma MS

Dr. Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi

rauma accounts for up to 12% of all rhegmatogenous 2. Peripheral : Iridodialysis retinal detachments (RRD) and is the most common T 3. Angle recession: tear between the longitudinal and cause of RRD in children. circular fibers of the ciliary muscle According to the USEIR (United States Registry): 4. Cyclodialysis: Separation of from the Retinal involvement is seen in up to 31 % among all serious injuries. Retinal involvement is seen in 34% of closed 5. Trabecular meshwork: Trabecular meshwork tear injuries (CGI) compared to 29% in open globe injuries (OGI). OGI is defined as presence of full thickness wound 6. Zonules/: Zonular tears with possible lens in ocular coats ( and ). In CGI there is no full subluxation thickness wound of the ocular coats. Vitreous involvement 7. Retinal dialysis: Separation or disinsertion of the is seen in 31% of all serious injuries. Vitreous involvement from the ora serrata almost doubles in open globe injuries as compared to closed (40% vs 22%). Rate of vitreoretinal involvement One must be aware and watchful of these trauma among all serious injuries is 44%. related sight threatening complications particularly angle recession. Gonioscopic evaluation of the angle in all Traumatic is most common in the 20-39 patients of blunt trauma must be done. Lifelong intraocular age group (nearly 50%) and is seen more in males (80%). pressure monitoring may be called for in patients with Closed Globe Injury angle recession. Globe deformation in four phases can explain the result of Mechanisms responsible for retinal break formation: the impact • Vitreous base avulsion: may occur at the anterior 1. Compression; attachment or posterior attachment of vitreous base. 2. Decompression; • Abnormal sites of vitreoretinal adhesion (e.g., lattice degeneration). 3. Overshooting; • Coup injury: Local trauma at the site of scleral impact 4. Oscillations. leads to a full thickness necrosis of the overlying retina. Ocular features of blunt trauma • Contrecoup injury- at a location opposite to the site of Campbell1 classically described the seven rings of blunt impact. trauma • Sudden posterior vitreous detachment induction. 1. Central iris: Sphincter tear

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Figure 1: Total RRD with subretinal bands.

Types of Breaks Figure 2: GRT with inverted flap. Ocular contusion may result in numerous types of retinal breaks, including horseshoe tears, operculated holes, large within 8 months, and 80% within 24 months4. irregular retinal breaks, macular holes, and, most often, Therefore one must do a complete peripheral examination retinal dialyses. and follow up the patient until media clears or 360° Retinal dialysis indentation indirect ophthalmoscopy is possible. Visualization of the peripheral retina will allow early It is defined as the disinsertion of retina from non diagnosis and treatment. In the young and uncooperative pigmented epithelium of the ciliary body at the ora serrata. patient general anaesthesia may be necessary. Repeated It is most commonly seen in inferotemporal quadrant, examinations may be needed if vitreous haemorrhage or accounting for almost 66% of cases, superotemporal in pre-retinal blood obscures the view. Sometimes the dialysis 10% and inferonasal in 4% cases and 6% in more than may be difficult to appreciate because of minimal separation one quadrant2. Though inferotemporal dialysis is the between retinal and ora. Particular attention should be commonest location of traumatic dialyses, superonasal given to the superonasal and inferotemporal quadrants. dialysis is pathognomonic of trauma. The inferotemporal Index of suspicion is warranted in case there is vitreous dialysis can also be seen in bilateral inferotemporal dialysis base avulsion which is classically described as a “bucket of young without a history of trauma. handle”. Occasionally, a dialysis may seal spontaneously Indirect ophthalmoscopy and scleral depression is due to a chorioretinal response to the insult. indispensable to rule out a dialysis and should be performed repeatedly until 360 degree ora can be visualised. The Peripheral retinal breaks clinical presentation of the traumatic retinal detachment The location and configuration of flap horseshoe or “U” is usually delayed as they occur most commonly in the tears tend to mimic those associated with a spontaneous young individuals. This may be attributed to well-formed posterior vitreous detachment. Tears from full-thickness vitreous being attached to the edge of the break. Typically retinal necrosis are usually slower to evolve and also tend there is no posterior vitreous detachment. Most frequently to be large, more irregular, and located at the site of direct the traumatic RRDs occur due to inferotemporal dialysis ocular contusion especially temporally where globe is which progress slowly, usually with multiple subretinal exposed maximally to external trauma. bands, multiple demarcation lines, intraretinal macrocysts (Figure 1) and patient notes its presence only when fovea is Giant retinal tears (GRT) involved. The superior field defect caused by inferior RRD GRT is defined as retinal tear involving 90° or more of is also rarely detected by the individuals as most routine the circumference of the globe (Figure 2). Myopic males works involve central and inferior visual fields. 12% of appear to be at a higher risk of developing giant retinal tears traumatic detachments are found immediately3. Thirty from blunt trauma. These are associated with significantly percent of traumatic RRD presents within 1 month, 50% more inflammation, hypotony, choroidal detachments, and

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proliferative vitreoretinopathy (PVR). PVR can progress retinal breaks may also occur because of vitreous traction very rapidly in a GRT. Vitreoretinal surgery in GRT requires bands which have resulted from the disturbance of the special considerations to prevent slippage of the posterior vitreous; these breaks tend to occur on the opposite side flap for which perfluorocarbon liquids (PFCL) are of great of the retina from the perforation site. The formation of the help. retinal breaks may be delayed for months or even years. Repeated fundus examination for a period of at least one Is contusion really the cause for retinal detachment? year should be carried out to allow early diagnosis of the Confusion arises because of coexisting causes of retinal retinal breaks before retinal detachment occurs. detachment namely trauma and pre-existing vitreoretinal degeneration. The one severe enough to cause RD, at Eitiopathogenesis times remains difficult to detect which may be important to Penetrating ocular injuries incite a sequence of events which differentiate particularly for medicolegal purposes. can ultimately lead to tractional and/or rhegmatogenous retinal detachment. This question was answered by Cox3 by giving the famous “Cox’s Postulates”. • Ocular wound leads to breakdown of the blood–retinal barrier and initiation of an inflammatory response. 1. ‘Unilateral retinal detachment preceded by ocular contusion. • Then cytokines are liberated which recruit retinal pigment epithelial (RPE) cells, fibroblasts, and glial 2. Objective signs of contusion in the affected eye. cells that proliferate within the eye. 3. Absence of visible vitreoretinal degeneration of the • These cells produce collagenous extracellular matrix types known to cause retinal breaks in both the affected in the vitreous and on the retinal surfaces causing it to and fellow eyes’. contract. At least one of the following objective signs of ocular • When the normal adhesive forces between the contusion is required to call the trauma significant: neurosensory retina and the RPE are overcome by • Vitreous haemorrhage the contractile forces, a tractional retinal detachment ensues • • Over weeks, the intraocular proliferation progresses, • Traumatic chorioretinal atrophy / pigmentation leading to the formation of cyclitic, epiretinal, and • Traumatic / subluxation retroretinal membranes. • Lid laceration/echymosis • Posterior vitreous separation generally occurs during the first 2 weeks of injury. • Corneal abrasion/scarring • Presence of vitreous haemorrhage expedites the • Iridiodiaylsis process. • Cycldialysis Here it is important to note that intervention in form of • Angle recession vitrectomy for penetrating trauma (in view of vitreous haemorrhage, metallic intraocular foreign body) should be Management undertaken immediately around this 2 week period for best Breaks without retinal detachment prognosis. This interval gives time for posterior vitreous detachment, better visualisation and better wound stability As the adage goes ’prevention is the best cure’ in posterior without significant proliferative changes. segment injuries too prophylactic treatment is advised in order to maintain good vision. It is imperative to localise Management of traumatic retinal detachment and treat all breaks with laser retinopexy which may be Traumatic retinal detachment is treated like any other done either on slit lamp with a or with the retinal detachment. The treatment options being: help of LIO in case of peripheral breaks or dialysis. The aim is to surround the break with 2 to 3 rows of moderate • Pneumatic retinopexy (for superior breaks, within 1 intensity burns. Cryoretinopexy may be used in case laser clock hour, if patient can maintain position, phakic is not available, media is hazy, very anterior break or it is patients) not possible to properly surround the break with laser. • Scleral buckling Open Globe Injuries • Vitreoretinal surgery In penetrating trauma retinal detachment can take place The choice of surgery mainly depends location of breaks / from linear breaks caused by the perforation itself. And amount of proliferative vitreo- and the surgeon’s

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preference. Below mentioned are the most acceptable • Traumatic , options. • Vitreous haemorrhage • Scleral buckling: may be the preferred surgery in • Type of break: GRTs are associated with more PVR cases of retinal dialysis, anterior breaks with fresh detachments especially inferior. Drainage may be done • Type of detachment: macula on vs macula off in long standing inferior detachments commonly seen • PVR following blunt trauma. It is also preferred in phakic young patients. For retinal dialysis this procedure has • anatomical success rate of 90-95%. • • Vitreoretinal surgery: vitrectomy may be preferred in • Intraocular foreign body cases with multiple breaks, posterior breaks, GRT and significant PVR. Penetrating globe injuries leading to Conclusion detachment are usually dealt with vitrectomy; this also includes detachments with retained intraocular foreign Traumatic retinal detachments present a different variety body. Dealing with PVR may be challenging and may of RRD which is usually seen with phakic young patients. require use of PFCL, relaxing retinotomy/ retinectomy, As dialysis is the commonest cause most cases can be removal of subretinal membranes and encirclage for successfully reattached with good visual recovery with anterior PVR. scleral buckling alone. Visual outcomes are better when the macula is on, the References height of macular detachment is less, and the macula is 1. Campbell DG. In Shingleton BJ, Hersh OS, Kenyon KR (eds), Eye detached for a short duration (less than 7-10 days). Trauma. St Louis, Mosby 1991. Prognosis depends on multiple factors: 2. Zion VM, Burton TC. Retinal dialysis. Arch Ophthalmol.1980;98: 1971–74. • Presenting visual acuity 3. Cox MS, Schepens CL, Freeman HM. Retinal detachment due to ocular contusion. Arch Ophthalmol 1966;76: 678-85 • RAPD 4. American Academy of , Basic and Clinical Science • Concomitant ocular trauma Course, Section 12: Retina and Vitreous. 2011; 278. • Macular hole, • Subfoveal/juxtafoveal choroidal rupture, • Sclopetaria,

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