[Comparison of astigmatism correction after limbal relaxing incisions combined with ICL implantation and Toric ICL implantation in patients with high myopia].

Objective: To investigate the efficacy and safety of limbal relaxing incisions (LRI) combined with implantable Collamer lens (ICL) implantation and Toric ICL (TICL) implantation in correcting high myopia with astigmatism. Methods: A prospective nonrandomized controlled clinical study was conducted. Patients with high myopia and astigmatism who underwent ICL implantation at Beijing Tongren Eye Center of Beijing Tongren Hospital Affiliated to Capital Medical University from March 1, 2022 to February 15, 2023 were enrolled in this study. These patients were divided into the TICL group (TICL implantation) and the LRI group (LRI combined with ICL implantation). The uncorrected distance visual acuity (UDVA) and corrected distance visual acuity (recorded as the logarithm of the minimum resolution angle), refractive power, corneal and anterior chamber conditions, surgically induced astigmatism, and target-induced astigmatism before and 1 and 3 months after surgery were observed. The correction index, efficiency index, and safety index were calculated, and predictability was observed. Statistical analysis was conducted using the independent sample t-test, Mann Whitney U test, and linear regression equation. Results: Twenty patients (20 right eyes) were included in the TICL group, and 17 patients (17 right eyes) were included in the LRI group. There was no statistically significant difference in preoperative visual acuity, refractive error, corneal astigmatism, corneal and anterior chamber conditions between the two groups (all P>0.05). At 1 and 3 months postoperatively, the UDVA of the TICL group [-0.10 (-0.10, 0.00), 0.00(-0.08, 0.00)] showed statistically significant differences compared to the preoperative value [1.30 (1.11, 1.49)] (both P<0.05). The postoperative UDVA in the LRI group [-0.10 (-0.10, 0.00), -0.08 (-0.08, -0.04)] also showed statistically significant differences compared to the preoperative value [1.30 (1.22, 1.46)] (both P<0.05). The difference in UDVA between the LRI group and the TICL group at 3 months postoperatively was statistically significant (P<0.05). The corneal astigmatism degree in the LRI group at 3 months postoperatively [(-0.87±0.47) D] was significantly different from that before surgery [(-1.32±0.91) D] (P<0.05). There was no statistically significant difference in the safety index (1.17±0.17 and 1.16±0.14) and efficacy index (1.12±0.18 and 1.18±0.16) between the two groups at 3 months postoperatively (both P>0.05). The achieved correction of refractive power of all operated eyes in both groups was within ±0.50 D of the attempted correction of refractive power at 3 months. There was no statistically significant difference in surgically induced astigmatism and target-induced astigmatism between the two groups (both P>0.05), and the correction index of both groups was slightly greater than 1. There were no complications during or after the surgical treatment in both groups. Conclusion: For high myopia with low to moderate astigmatism, LRI combined with ICL implantation has good efficacy, safety, and predictability in the early to mid-term postoperative period.