A Comparative Study to Assess Surgically  Induced Corneal Astigmatism in Superior  and Temporal Scleral Incision in Manual  Small Incision Cataract Surgery

Dr.R.S.Umadevi; Dr.Kirthi Raj

Volume : II, Issue : VII, July - 2013

A Comparative Study to Assess Surgically Induced Corneal Astigmatism in Superior and Temporal Scleral Incision in Manual Small Incision Cataract Surgery

Dr. R. S. Umadevi, Dr. Kirthi Raj

Abstract :

Background and objectives: Cataract is a public health problem in many developing countries. Astigmatism forms a major cause of unsatisfactory visual results after cataract surgery using manual SICS (small incision cataract surgery) technique and is mainly of corneal origin. This study was taken up to assess the role of superior and temporal incision in surgically induced corneal astigmatism among patients undergoing manual small incision cataract surgery. Materials and Methods: In our study, 30 cases were randomly assigned for temporal scleral group(Group1) and other 30 cases were allotted to superior scleral incision manual SICS with PCIOL (posterior chamber intraocular lens) implantation were performed through unsutured 6.5mm scleral incision(Group2). In all 60 patients were examined pre and post operatively 1st day, 2nd week, 4th week and 6th week after surgery SIA (surgically induced astigmatism) was calculated using SIA calculator 2.1. Results: Post operatively after 6 weeks in superior incision group a drift of +26.7% was seen towards the ATR(against the rule) astigmatism and in the temporal incision group +33.3% of the patients drifted towards WTR(with the rule) astigmatism. The mean SIA centroid was found to be reduced in the temporal incision group (0.48x86) compared to superior incision group (1.11x1.78). After 6 weeks 33.3% of patients in superior had visual acuity better than 20/30 and in temporal group 80% of the patient had visual acuity better than 20/30. Conclusion: The superior incision is likely to induce about 1.11D of astigmatism as suggested by the centroid (1.11x178o ). Temporal scleral incision is recommended except in patients with pre-existing WTR astigmatism. Visual rehabilitation is better and early in temporal incision than superior.