AIM: To evaluate the efficacy and safety of limbal relaxing incision(LRI)for correcting corneal astigmatism during implantable collamer lens(ICL)surgery.

METHODS: A total of 185 eyes of 105 patients with high myopia and corneal keratometric astigmatism were included in the study. ICL surgery with concomitant relaxing incision was performed in 105 eyes of 60 patients in LRIs group(Group A). Eighty eyes of 45 patients only underwent ICL surgery were in control group(Group B). All patients undergone ophthalmic examination that included uncorrected visual acuity(UCVA), best-corrected visual acuity(BCVA), Pentacam analysis system to observe the changes of corneal astigmatism before and 1wk, 1 and 3mo after surgery.

RESULTS: Respectively comparing UCVA between two groups in 1 and 3mo postoperatively, the P values were considered statistically significant(P<0.05). But, respectively comparing BCVA between two groups in 1wk, 1 and 3mo postoperatively, the P values were considered no statistically significant(P>0.05). Preoperative corneal astigmatism was 1.52±0.55D in group A and 1.48±0.57D in group B, there was no statistically significant difference(P>0.05). One week postoperatively, the astigmatism was 0.55±0.41D in group A and 1.20±0.48D in group B. One month postoperatively, the astigmatism was 0.60±0.38D in group A and 0.93±0.47D. Three months postoperatively, the astigmatism was 0.51±0.32D in group A and 0.96±0.40D in group B. The difference between the two groups were statistically significant(P<0.05). The difference value of corned astigmatism before surgery and 1wk, 1 and 3mo after surgery had statistical significance(P<0.05). In LRIs group, at preoperative and postoperative time points, the average corneal astigmatism changes were also considered statistically significant difference(P<0.05).

CONCLUSION: LRIs performed during ICL surgery appeared to be an effective and safer procedure to reduce pre-existing corneal astigmatism and improve UCVA as well as the visual quality.