Comparison of astigmatism correction following straight and frown incisions in manual small incision cataract surgery
Materials and methods: A prospective interventional cross-sectional study was conducted in the Department of Ophthalmology. 100 patients admitted for cataract surgery between the age group of 45 to 70 years were only considered for the study.
Results: The observation of astigmatism in diopters preoperatively revealed 48% had astigmatism -0.25 D, 36% has astigmatism range from 0.26 to 0.50 D, 14% had astigmatism range from 0.51 to 0.75 D, and 2% had astigmatism range from 0.76 to 1.00 D. The course of post-operative astigmatism in relation to preoperative status in patients with frown incision revealed majority showed shift toward WTR astigmatism in the first postoperative week, then the ATR astigmatism increases progressively up to 3 weeks and starts stabilizing at 3 weeks. However, in straight incision, the patients showed a shift toward WTR astigmatism at first postoperative week; then the ATR astigmatism increases progressively up to 3 weeks and stabilizes at 4 to 6 weeks. The best corrected visual acuity at 6 weeks of 6/9 or better following frown and straight SICS were 50 and 37% respectively, 1st week postoperatively; 77 and 53% respectively, 3rd week postoperatively; and 83 and 77% respectively, 6th week postoperatively. In our study, we found that frown incision had significantly better (p < 0.001) mean net astigmatism as compared with the straight incision.
Conclusion: We conclude that small incision size and absence of suture are the most important factors that contribute to less astigmatism and faster stabilization of SICS. The duration for stabilization of postoperative astigmatism in straight incision group is 6 weeks, whereas it is 3 weeks in frown incision