Clinical efficacy of implantation of toric intraocular lenses with different incision positions: a comparative study of steep-axis incision and non-steep-axis incision

BACKGROUND: To compare the clinical outcomes after implantation of AcrySof Toric IOLs with different clear corneal incisions. METHODS: Sixty cataract patients with regular corneal astigmatism who underwent phacoemulsification combined with implantation of an AcrySof Toric IOL were enrolled. They were divided into two groups according to the position of the clear corneal incision: steep-axis and non-steep-axis. Main outcome measurements included visual acuity, residual astigmatism and changes of corneal astigmatism 3 months postoperatively. Deviation of IOL axis according to the re-calculation using the actual surgically induced astigmatism (SIA) and visual function 3 months after surgery were also evaluated. RESULTS: The corneal astigmatism decreased significantly in steep-axis group 3 months postoperatively (P < 0.05). Besides, more patients in non-steep-axis group were with irregular corneal astigmatism after the surgery (43.33% vs 10%, P = 0.004). The deviation of IOL axis according to the re-calculation using the actual SIA was significantly larger in non-steep-axis group than that of steep-axis group (P < 0.001). Moreover, the postoperative visual function was better in eyes of steep-axis group in various measurements, including point spread function, modulation transfer function and high-order aberrations. CONCLUSION: Steep-axis clear corneal incision could reduce the cylinder power of toric IOL and lower the chance of postoperative irregular astigmatism, which may consequently improve the postoperative visual quality.