Effect of 2.2 mm opposite clear corneal incisions post phacoemulsification on total corneal astigmatism in a tertiary eye hospital of Eastern India

PURPOSE: To determine the change in total corneal astigmatism (ΔTK) in patients undergoing cataract surgery with 2.2 mm opposite clear corneal incisions (OCCIs). DESIGN: Retrospective cohort study. METHODS: This study determined the change in ΔTK in patients undergoing phacoemulsification with monofocal intraocular lens implantation with 2.2 mm OCCIs using an image-guided system over 1 month and 3 months postoperatively from 1st January 2023 to 30th June 2024 at a tertiary eye hospital. Manifest astigmatism and final uncorrected visual acuity (UCVA) were analyzed at the 3rd month postoperatively. The secondary objective was to elicit the change in astigmatism from baseline to the 3rd month in different astigmatism groups: Mild (1-1.5 diopters [D]), moderate (1.6-2 D), and severe (>2D). RESULTS: A total of 39 eyes were included in the analysis. This study showed that 2.2 mm OCCIs significantly reduced astigmatism in mild (ΔTK: 1.22 ± 0.17-0.87 ± 0.25 D; P < 0.001) and moderate (ΔTK: 1.67 ± 0.15-1.27 ± 0.41 D; P < 0.001) groups from baseline to 1st month and 3rd month. Manifest refraction showed no significant astigmatism change at 1 month but a significant reduction occurred by 3 months. UCVA improved significantly in the mild group from 25.6% to 48.7%, achieving 0-0.2 Logarithm of the Minimum Angle of Resolution (LogMAR) by 3 months, while the moderate and severe groups showed no significant changes. CONCLUSION: Using a 2.2 mm keratome for the main incision as well as OCCIs during phacoemulsification stands out as a safe, effective, and notably low-cost method for correcting a mild-to-moderate degree of astigmatism.