Surgical Induced Astigmatism in Superior vs Temporal Incision in Small Incision Cataract Surgery- A Comparative Study

Abstract

BACKGROUND Cataract surgery is a boon in itself. With all the possible modalities of cataract surgery, we try to give a normal vision. But Surgically Induced Astigmatism (SIA) is one of the causes of a poor quality of vision. We have studied SIA in 2 different sites of incision in Manual Small Incision Cataract Surgery (SICS). The objective of this study is to compare the amount of surgically induced astigmatism in superior and temporal incisions in manual small incision cataract surgery. MATERIALS AND METHODS Hundred patients were studied. The patients were randomly assigned to any of the two groups. The two groups had 50 patients each. The patients in Group A underwent manual SICS with a superior incision. The patients in Group B underwent manual SICS with a temporal incision. The patients were examined on the post-operative weeks 1, 3 and 6. The uncorrected and the bestcorrected visual acuity was recorded and a slit-lamp examination and auto-refractometer and keratometry examinations were also done. RESULTS In our study at 6 weeks post-operatively we found almost 80% people with astigmatism < 0.5D in temporal section, while there were 20% people in superior section. We also found that in temporal sclera group, there was reduction of pre-operative ATR astigmatism from 66% to 64% and there was no change in pre-operative WTR astigmatism which was 30% pre-and postoperative (6 weeks). CONCLUSION SICS which is done with a temporal approach provides a better quality of vision due to a significantly less SIA than the superior approach.