LASIK for correcting irregular astigmatism and asymmetrical astigmatism guided by corneal topography

Abstract

Objective To discuss the effect of laser in situ keratomileusis (LASIK) for correcting irregular astigmatism and asymmetrical astigmatism guided by corneal topographic map.Methods There were 58 cases( 108 eyes) with compound myopic astigmatism,asymmetric or irregular corneal astigmatism accepted LASIK under MEL- 70 excimer laser that guided by TOMEY-Ⅲ corneal topography.49 patients (97 eyes) received their first operation on the eye.9 patients ( 11 eyes) with irregular astigmatism due to uneven cutting,eccentric cutting or central island received the second operation on the same eye.The preoperative best corrected visual acuity was on average of 0.98 ± 0.32,Sphere ( - 4.59 ± 1.68 ) D,Cylinder ( - 1.62 ± 0.78) D.Results 108 operations were successfully finished without intraoperative or postoperative complications.Corneal topography showed the centra 3 mm cutting was depth uniform,smooth.One week Postoperatively,uncorrected visual acuity was on average of 1.03 -± 0.29.Diopter:Sphere:- 0.50 D ～ +0.75 D with an average of( -0.35 ±0.29) D; Cylinder:0 ～ -0.75 D with an average of ( -0.38 -±0.24) D.Conclusion TOMEY - Ⅲ corneal topography could capture the corneal curvature information accurately,it is fit for guiding personalized LASIK in correcting irregular astigmatism and asymmetrical astigmatism. Key words: Astigmatism, irregular; Astigmatism, asymmetrical; Corneal topography; Excimer laser; Customized ablation