Early postoperative astigmatism in 2-mm manual small incision cataract surgery with phacofracture

Abstract

Purpose: India's cataract surgery rate has been hovering around a creditable 6000 per million population but the coverage is variable across the geography and demography with sharp urban rural divide. Smaller incisions in manual small incision cataract surgery (MSICS) with phacofracture have been credited with lower astigmatism and faster recovery, which is especially useful for patients traveling for surgeries. Methods: In this retrospective chart analysis based observational study of 66 eyes, we describe the early postoperative results with 2 mm MSICS with phacofracture. Results: The mean spherical equivalent of the autorefractor measured astigmatic error changed marginally to -0.51 diopters (SD = 0.58) from -0.44 diopters (SD = 0.42) (t = -8.410, P = 0.0) translating to mean change in astigmatism of 0.14 DCyl when the axis was ignored. The keratometric difference between steepest and flattest axis of the anterior surface of the central 3 mm zone of the cornea changed from a mean of 0.89 diopters (SD = 0.55) to 1.39 diopters (SD = 1.03). The visual acuity improved to mean logarithm of the minimum angle of resolution (logMAR) score of 0.27 (SD = 0.33) at 1 week and 0.007 (SD = 0.04) which corresponds to 6/6P on Snellen's acuity at 1 month or more. Conclusion: A 2 mm MSICS with phacofracture can deliver low astigmatism and good visual recovery in cataract surgery. The study underlines the need for considering the refraction at anterior and posterior corneal interfaces when the triplanar incision with separate interfaces is used.