Comparison between opposite clear corneal incision versus toric intraocular lens in correcting astigmatism.

PURPOSE

To compare the visual outcomes and efficacy of opposite clear corneal incision (OCCI) and toric intraocular lens (IOL) implantation in correcting preexisting astigmatism (PEA) in patients undergoing phacoemulsification.

METHODS

This prospective interventional comparative study was conducted between June 2022 and January 2023 in patients having cataract with PEA undergoing phacoemulsification. Patients were divided into two groups - group A underwent phacoemulsification with OCCI and group B underwent phacoemulsification with toric IOL implantation. Uncorrected distance visual acuity (UDVA), manifest refractive cylinder, and corneal astigmatism using corneal tomography were measured preoperatively and at 6 weeks postoperatively. The eyes were categorized into three groups with PEA ranging from 1 to 1.5 D, 1.6 to 2 D, and 2.1 to 3 D. Depending upon the white-to-white corneal diameter, the eyes were also categorized into four groups with corneal diameter ranging from 10.5 to 10.9 mm, 11 to 11.4 mm, 11.5 to 11.9 mm, and 12 to 12.4 mm.

RESULTS

Sixty eyes of 60 patients were studied. At postoperative 6 weeks, 83.3% (25 eyes) in the OCCI group and 96.7% (29 eyes) in the toric IOL group achieved UDVA of 6/9 or better. No statistically significant difference was noted between the groups ( P = 0.37). The reduction in mean corneal astigmatism was 0.63 ± 0.37 D in the OCCI group and 0.15 ± 0.12 D in the toric IOL group ( P < 0.001). The residual mean refractive cylinder was 0.60 ± 0.38 D in the OCCI group and 0.05 ± 0.15 D in the toric IOL group at 6 weeks ( P = 0.007).

CONCLUSION

Both OCCI and toric IOL are effective in correcting PEA. However, in a resource-limited setting, OCCI is a better alternative surgical option for correcting astigmatism of 1-1.5 D during phacoemulsification without requiring additional skills or instruments.