RISK FACTORS FOR RETINAL DETACHMENT AFTER PROPHYLACTIC LASER TREATMENT OF RETINAL LESIONS

Prevention of rhegmatogenous retinal detachment (RD) in susceptable eyes is necessary. In order to evaluate the role of signs and symptoms of the treated eyes in preventing RD, this study performed in prophylactically laser treated (PLT) eyes in Rasul-e Akram Hospital from 1991 to 1999.This is an exisiting data study from the records of the patients who underwent PLT around the retinal lesion and had at least 1 year follow up. Collected data were age, sex, refractive error, kind of retinal lesion patients symptoms, previous history of trauma or surgery on the eye, aphakia, noticed decreased visual acuity (VA), floaters and flashing, trauma to the eye. According to VA, the eyes divided in 3 groups of less than 1/10, 1/10-6/10 and more than 6/10. According to the refractive errors they are divided in 3 groups of non-myopic, myopia of less than 5.75 diopters and more than 6, and according to the type of retinal lesions that were treated divided in horse shoe tear (HST), Hole, lattice and dialysis. Collected data were classified and analysed by X2 test to evaluated the role of each factor for chance of post treatment RD. One hundred and twenty-one eyes from 114 patients that had 13 to 92 months (mean 23 months) follow up were considered for this study. Age distribution was 19-74 years(mean 50 years). From 121 treated eye 13.2%(16) developed RD. The rate of RD was 7.3%(2/41) in eyes with history of RD in the other eye, 20.7%(6/24) eyes with decreased VA due to vitreous hemorrhage, 15%(3/20) in aphakics, 11.8%(2/17) in eyes with floaters, 28.5%(2/7) with flashing, 14.2%(2/7) with history of trauma to the eye, with a significant statistical relation between these symptoms and chance of RD (X2, P = 0.002). Rate of RD was 21.6%(8/37), 9.6%(3/31), 6%(2/33) in eyes with VA of less than 1/10, 1/10-6/10 and more than 6/10 respectively, with no significant statistical differences. RD chance was 17%(9/52) in eyes with more than 6 diopter myopia, 11.4%(4/35) of myopia less than 5.75 diopters, and no RD in non myopic eyes, 16.2%(7/43) for HST, 7.4%(2/27) for retinal hole, 12%(3/25) of lattice and 16.6%(1/6) eyes with dialysis, but no significant statistical differences was observed. Although PLT could prevent RD in susceptable eyes but its prophylactic effect is not 100%. Chance of RD is higher in eyes with photopsia, history of trauma, HST, high myopia and VA of lees than 1/10. Further clinical trial to prevent RD in recomended.