Effects of two different femtosecond laser surgeries for the treatment of thin corneal myopic astigmatism
- VernacularTitle:2种不同飞秒激光术治疗薄角膜近视散光的效果分析
- Author:
Chuanhai ZHOU
1
;
Lijun WANG
;
Yuanxu HE
;
Dong QIN
Author Information
- Keywords: femtosecond laser-assisted in situ keratomileusis; small incision lenticule extrac-tion; thin cornea; myopia; astigmatism; visual acuity
- From: Journal of Clinical Medicine in Practice 2024;28(20):48-54
- CountryChina
- Language:Chinese
- Abstract: Objective To explore the effect of femtosecond laser-assisted in situ keratomileusis(FS-LASIK)and small incision lenticule extraction(SMILE)femtosecond laser in the treatment of myopic astigmatism with thin cornea.Methods From September 2022 to September 2023,128 pa-tients with thin cornea myopic astigmatism in the hospital were selected and randomly divided into FS-LASIK group(64 cases,128 eyes,receiving FS-LASIK)and SMILE group(64 cases,124 eyes,receiving SMILE).The visual acuity[uncorrected visual acuity(UCVA),best corrected visual acuity(BCVA)]before surgery and at 1 year after surgery,refractive parameter spherical equivalent(SE)at 3,6 and 12 months after surgery,corneal surface morphology[average corneal curvature(KAve),surface regularity index(SRI),surface asymmetry index(SAI)]before surgery and at 1 year after surgery,corneal biomechanic indicators[corneal expansion comprehensive deviation analysis index(BAD-D),corneal biomechanical index(CBI),total biomechanical index(TBI)]and corneal injury degree[corneal endothelial cell count,corneal endothelial cell size,coefficient of variation(C V)]and differences in postoperative astigmatism correction vector indicators[magnitude of error(ME),angle of error(AE),correction index(CI),and index of success(IOS)]were compared.Residual stromal bed thickness and the incidence of complications after surgery were recorded.Results One year after surgery,both UCVA and BCVA in both groups were improved compared with preoperation(P＜0.05),but there were no significant between-group differences(P＞0.05).At 3,6,and 12 months postoperatively,the SE levels in both groups were higher than preoperation(P＜0.05);however,there were no statistically significant differences in SE levels between the groups at above time points(P＞0.05).One year after surgery,KAve,SRI,and SAI in both groups were lower than preoperative levels,and the SMILE group was lower than those in the FS-LASIK group(P＜0.05).One year after operation,BAD-D and TBI in both groups were higher than preoperative levels,while CBI was lower than preoperative levels;however,BAD-D and TBI in the SMILE group were lower than those in the FS-LASIK group,and CBI was higher than that in the FS-LASIK group(P＜0.05).One year after surgery,corneal endothelial cell counts in both groups were lower than preop-erative levels,and CV of corneal endothelial cell size was higher than preoperative levels;however,corneal endothelial cell count in the SMILE group were higher than those in the FS-LASIK group,and the CV of corneal endothelial cell size was lower than that in the FS-LASIK group(P＜0.05).There were no statistically significant differences in ME,AE,CI,and IOS between the two groups(P＞0.05).The residual stromal bed thickness was(302.01±55.03)μm in the FS-LASIK group and(310.23±46.03)μm in the SMILE group after surgery,with no statistically significant be-tween-group difference(t=1.284,P=0.200).One year after surgery,there were 5 cases of dry eye in the FS-LASIK group and 2 cases in the SMILE group,with no statistically significant differ-ence in incidence of dry eye between the two groups(x2=1.227,P=0.268).Conclusion For patients with myopic astigmatism with thin cornea,both FS-LASIK and SMILE can achieve satisfac-tory improvement in visual acuity and refractive state,and the latter one has a relatively small impact on the integrity of corneal structure,biomechanical stability and surgical injury.
