Background: This study aimed to compare changes in central corneal thickness (CCT) and endothelial cell count following small incision cataract surgery between immature and mature cataracts.

Methods: A hospital-based observational study was conducted on 60 patients (51.7% male, 48.3% female) who underwent manual small incision cataract surgery. The study population comprised 30 immature and 30 mature cataract patients. The patients were evaluated preoperatively and on days 1, 1 week, 6 weeks, and 12 weeks postoperatively.

Results: Postoperative CCT increased on day 1 (immature: 544.33µm, mature: 555.43µm) and then gradually decreased to near preoperative levels by the 6th week (immature: 494.9µm, mature: 495.83µm). The immature cataract group exhibited a higher mean preoperative endothelial cell count (2574.03 cells/mm²) than the mature group (2447.46 cells/mm²). Although both groups experienced a decrease in endothelial cell count, the immature group maintained a higher count throughout the postoperative period, reaching 2276.23 cells/mm² by the 3rd month, compared to 2072.43 cells/mm² in the mature group. Visual acuity showed significant improvement postoperatively, with 96.7% of immature and 90% of mature cataract patients achieving a visual acuity of 6/6 to 6/18 at the 6th week.

Conclusion: Small incision cataract surgery has a minimal long-term impact on corneal thickness and results in a manageable decrease in endothelial cell count in both immature and mature cataracts.