Giant Retinal Tears

A comprehensive account on the current management trends of giant retinal tears

1. GIANT RETINAL TEARS DULEEPA BARANAGE Senior Registrar in Vitreo -Retinal Surgery

2. INTRODUCTION Full thickness, circumferential tears of more than 90⁰ of retina Associated with vitreous detachment Can occur spontaneously, but often associated with number of conditions

3. INCIDENCE / AEITIOLOGY 1.5% of RRDs Average age – 42 years Males 72% Causes Idiopathic - 54% High myopia – 25% Hereditary conditions – 14% Mafans’s , Stickler-Wagner, Ehrler Danlos Xd Trauma – 12.3% Bilateral in 12.8% Incidence – 0.05/100,000 per year

4. PATHOGENESIS Liquefaction of central vitreous Peripheral vitreous condensation Concomitant traction at the vitreous base The neurosensory retina tears circumferentially in the area of the posterior vitreous base Vitreous gel attached to the anterior flap Posterior flap moves freely and can fold upon itself [In retinal dialyses the vitreous is adherent to the posterior aspect of the retinal tear, therefore the retina is not very mobile – laser/ scleral buckle]

5. MANAGEMENT Perfluorcarbon liquids were described by Stanely Chang in 1987 Increased the primary attachment rate from 58% to over 94% (inverted surgical beds/ retinal tracks/ sutures..) Options… Laser photocoagulation Scleral buckle Primary vitrectomy with PFCL Vitrectomy + buckle Combined phaco / vitrectomy

6. Laser When the retina is attached Edge of the tear is treated with 2-4 rows of photocoagulation Particularly the radial edges of the tear, treat anteriorly up to the ora serrata Scleral buckle If the edge is not inverted Good option in children (lens protection/ positioning) Support of the edges + cryo /laser PPV + PFCL + gas/ SiO tamponade To unroll and reposition a folded retina PPV + buckle In PVR

7. 25‑gauge vitrectomy… ADVANTAGES Less trauma Smaller incisions Reduced sclerotomy complications Shortened surgical times CHALLENGES Slower removal of vitreous Some difficulty reaching the anterior retina and vitreous near the ora serrata Flexible instruments More prolonged aspiration time during the air/ fluid exchange (crucial to prevent retinal slippage)

8. SURGICAL TECHNIQUES

9. Removal of all the vitreous posteriorly and injection of perfluoro‑octane liquid over the optic nerve Done slowly with a dual bore cannula (to prevent trauma and IOP elevation) PFCL as a single bubble (prevent fish eggs)

10. 2. Once the retina is stabilized posteriorly, the anterior vitreous and the anterior retinal flap are removed Chandelier illumination and scleral depression aid in the visualization Paramount to remove all the vitreous, esp. the corners (to prevent redetachment )

11. 3. More PFCL is added to further flatten the retina over the level of the edge of the tear Keep the PFCL level below the infusion to avoid the formation of fish eggs Retina can be unfolded with forceps, with a soft‑tip cannula or with a vitreous rake loop

12. 4. All of the anterior flap and vitreous need to be thoroughly removed Especially all possible vitreous traction on the corners since this is the area where any residual vitreous traction can cause proliferation, traction and redetachment

13. 5. If epiretinal membranes, star folds, or macular holes are present, membranes and the ILM can be peeled through the PFCL Staining can be done prior to injecting PFCL

14. 6. Laser is applied to the corners and edge of the tear Two to three rows up to the ora serrata Using a curved laser probe Rest of the retina should be checked for small breaks etc..

15. 7. Fluid – Air Exchange Aspiration of all fluid anterior to the PFCL meniscus with a soft tip cannula To prevent retinal slippage Residual PFCL aspirated over the optic nerve Eye filed with minimally expanding conc. of gas If SiO used direct PFCL/ SiO exchange preferred to prevent retinal slippage

16. PHAKIC EYES PRESERVE THE LENS Chandelier illumination – scleral depression can be used to remove the anterior flap without causing trauma to the lens Advantage- accurate lens calculations/ risk of losing pupillary dilatation from lens removal is avoided Disadvantage – technically difficult to clear the anterior vitreous and retinal flap PHACOEMULSIFICATION / PARS PLANA LENSECTOMY Concomitant / secondary IOL Advantage – easier access to anterior vitreous Disadvantage – extra procedures / imprecise lens calculation / poor visibility due to pupillary miosis

17. PROLIFERATIVE VITREORETINOPATHY Not uncommon in GRT RPE dispersion + VH Occur in 45% More in trauma / chronic Pre-placing an encircling silicone scleral buckle (#41/#42) Removal of all fibrous proliferation on both surfaces of the retina Subretinal before and on the surface after PFCL injection Scleral buckle is placed and vitrectomy done as described above Scleral buckle NOT ROUTINELY RECOMMENDED in eyes without PVR Creation of retina redundancy > guttering > retinal slippage

18. COMPLICATIONS Retinal slippage during PFCL removal Retinal folds associated with slippage, SB or high myopia Residual PFCL Cataract progression Recurrent RD with PVR Re-detachment Causes : Anterior traction and re-proliferation at the corners Missed breaks away from the tear Concomitant macular holes PVR (old/ blood/ pre-existing membranes/ pre-existing PVR)

19. RESULTS Rate of reattachment following single procedure is 80 - 90% Final reattachment rate 94-100% In PVR – visual prognosis poor (despite reattachment and anatomical success)

20. OTHER EYE 12.8% develop bilateral GRTs High risk in: High myopes White without pressure Vitreous condensation Peripheral pathology should be treated with laser Prophylactic buckle – controversial

21. THANK YOU