To assess the safety and efficacy of two SCOLI designs (Yang's I/II) for astigmatism correction in manual cataract surgery and define incision size-astigmatism relationships.A total of 72 eyes from 64 cataract patients who accept manual cataract extraction surgery via a SCOLI technique. The two different types of incision: Yang's I and II incisions were applied in this study. The patients were divided into four groups based on corneal topography: Group 1 (0.25-1.5D), Group 2 (1.5-2.5D), Group 3 (2.5-3.5D), and Group 4 (>3.5D). In both groups, the incisions of different lengths were made on the steepest axis. 1 day, 1 week, 1 month, and 3 months after surgery, the postoperative corneal topography was examined, and the surgically induced astigmatism (SIA) was computed by an open-source software SIA calculator.Seventy-two eyes of 64 cataract patients were analyzed in this study. The difference in average K preoperative (44.29 ± 1.68) and 3 months postoperative (44.32 ± 1.71) was not statistically significant (P = 0.529). The mean SIA at 3 months was 0.67 ± 0.16 D (Group 1), 1.54 ± 0.42D (Group 2), 2.04 ± 0.35D (Group 3), and 3.74 ± 1.83 D (Group 4). Statistically significant SIA changes were found among different groups (all P < 0.05). The SIA at 1 day was statistically significant compared to the SIA at 3 months (P = 0.013). The DAP plots showed displacement of the centroid from the periphery toward the center in all groups.SCOLI merges refractive precision with manual cataract extraction, offering a suture-free, adaptable solution for astigmatism correction (0.25-4.5 D). Its cost-effectiveness and safety profile make it particularly viable for resource-limited settings.Copyright © 2025 Indian Journal of Ophthalmology.