AIM: To compare the clinical efficacy, vault, and rotational stability of horizontal, oblique, and vertical implantation of Toric implantable collamer lens(TICL).

METHODS: Retrospective cohort study. A total of 92 cases(120 eyes)who underwent TICL implantation from July 2018 to March 2022 and had regular follow-up for at least 1 a postoperatively(1 d, 1 wk, 1, 3, 6 mo, and 1 a)at Wuhan Bright Eye Hospital were collected. The patients were divided into three groups, with 34 cases(45 eyes)in horizontal implantation group, 25 cases(29 eyes)in oblique implantation group(29 cases), and 33 cases(46 eyes)in vertical implantation group. Uncorrected distance visual acuity(UDVA), corrected distance visual acuity(CDVA), diopters, vault, and rotation angle(deviation of the actual axis of TICL from the expected axis).

RESULTS: All surgeries were uneventful, and there were no complications such as infection, secondary glaucoma, or cataract opacity. Safety and efficacy of the surgery: the CDVA of the three groups of patients was better than or equal to the preoperative CDVA at 1 a postoperatively, and there was no statistically significant differences in postoperative UDVA and CDVA of the three groups(P>0.05). The safety index at 1a postoperatively was 1.34±0.21, 1.34±0.17, and 1.31±0.18 for the horizontal, oblique, and vertical groups, respectively. The efficacy index was 1.26±0.21, 1.33±0.18, and 1.27±0.16 for the three groups, respectively, both with no statistically significant differences(P>0.05). Vault: there was a significant difference in postoperative vault among the three groups(P=0.003), with the vertical group having the lowest vault, followed by the horizontal group and the oblique group. The vaults at different follow-up time points within each group showed significant differences(P<0.001), and all decreased over time. Residual astigmatism: there was no significant difference in residual astigmatism among the three groups(P=0.130), but there were differences at different follow-up time points within each group(P<0.001). Rotation angle: no significant differences in rotation angle were observed among the three groups(P=0.135), but there were differences at different follow-up time points within each group(P<0.001).

CONCLUSION: The implantation of TICL in different orientations has good safety and efficacy, the postoperative rotational stability is good, and the appropriate angle can be selected to implant TICL according to the clinical situation.