Nevin Manimala Statistics

Effect of two different preoperative calculation schemes on visual outcomes of patients after toric intraocular lens implantation

Int Ophthalmol. 2022 Aug 6. doi: 10.1007/s10792-022-02447-7. Online ahead of print.


PURPOSE: To compare the postoperative visual outcomes of two different preoperative corneal incision schemes in TECNIS toric intraocular lens (IOL) implantation.

METHODS: In this randomized controlled study, patients with preoperative corneal astigmatism greater than 1.0 diopter (D) were included. These patients were grouped according to the different preoperative schemes: steep-axis group and minimum-residual refractive astigmatism group. The outcome measurements were the residual refractive astigmatism, visual acuity, changes of corneal astigmatism, and high-order aberration at 1 month postoperatively.

RESULTS: This study consisted of 90 eyes (45 eyes steep-axis group, 45 eyes minimum-residual refractive astigmatism group). 1 month after surgery, the refractive astigmatism was statistically lower in the minimum-residual refractive astigmatism group compared with the steep-axis group (0.58 ± 0.40D vs 0.38 ± 0.37D, P = 0.021). The minimum-residual refractive astigmatism group had a smaller difference vector (0.56 ± 0.38D vs 0.36 ± 0.35D; P = 0.047) and a smaller prediction error (0.60 ± 0.44D vs 0.37 ± 0.35D; P = 0.004). In the steep-axis group, corneal astigmatism significantly decreased compared with preoperative value (1.65 ± 0.57D vs 1.17 ± 0.64D; P < 0.001). In the minimum-residual refractive astigmatism group, the changes of corneal astigmatism before and after surgery were not significant. Moreover, total aberration and second astigmatism in ocular aberration were lower in the minimum-residual refractive astigmatism group compared with the steep-axis group (1.86 ± 1.09 vs 1.37 ± 0.95; P = 0.035 and 0.47 ± 0.28 vs 0.31 ± 0.19; P = 0.015, respectively).

CONCLUSION: Minimum-residual refractive astigmatism incision had better astigmatism correction and more accurate prediction. The corneal astigmatism was stable 1 month after surgery. It might lead to better visual quality in the early postoperative stage. Trial registration number for prospectively registered trials: NCT04006912, 07/02/2019.

PMID:35932419 | DOI:10.1007/s10792-022-02447-7

By Nevin Manimala

Portfolio Website for Nevin Manimala