Comparative Study of Surgically Section Induced Astigmatism in Manual Small Incision Cataract Surgery

Introduction: Various types of incisions have been adopted and applied in Manual Small Incision Cataract Surgery (MSICS) with the primary objective to attain minimum postoperative Surgically Induced Astigmatism (SIA).

Aim: To evaluate and compare the postoperative visual acuity and to determine SIA in Batwing incision and Frown incision in MSICS.

Materials and Methods: The present study was a prospective, cross-sectional, interventional, comparative descriptive study in which a total of 380 patients aged 40 years and above with senile, uncomplicated cataract, undergoing MSICS were included. Patients were randomly divided into: Group B (Batwing incision), and Group F (Frown incision). Patients were compared on 6th week postoperatively for Uncorrected Visual Acuity (UCVA), Best Corrected Visual Acuity (BCVA) and SIA (performed using SIA Calculator Version 2.1). The data was collected in terms of demographic, clinical and biochemical characteristics that were expressed as range, mean and median and subjected to statistical analysis to obtain results.

Results: In group F, total 04 (2.11%) patients showed no astigmatism, 115 (60.53%) patients showed 0-0.5D of SIA, 64 (33.68%) were seen with 0.5-1D of SIA and 07 (3.68%) patients with 1-1.5 D SIA, no patient showed SIA more than 1.5 D. In Group B 01 (0.52%) patient showed no SIA, in 61 (32.11%) 0-0.5D of SIA was seen, in 79 (41.58%) patients 0.5-1D of SIA was seen and 45 (23.68%) patients had presented with 1-1.5D of SIA while 04 (2.11%) patients with more than 1.5D of SIA. In group F, average preoperative astigmatism preoperatively was 0.55±0.36D and average astigmatism at six weeks postoperatively was 0.46±0.33D. In Group B, average preoperative astigmatism was 0.49±0.39D and average astigmatism six weeks postoperatively was 0.54±0.40D.

Conclusion: The present study showed the superiority of Frown incision over Batwing incision in terms of less SIA and improved postoperative unaided visual results.