Vector analysis of correction of astigmatism by Epi-LASIK and the relationship between the result of analysis and the change in visual quality

Abstract

AIM: To evaluate the outcome of astigmatism correction after epipolis laser in situ keratomileusis(Epi-LASIK)by standardized vector analysis, and to investigate the relationship between the result of analysis and the change in contrast sensitivity function(CSF). METHODS: Totally 68 myopic astigmatism eyes treated with Epi-LASIK. The myopic diopter was range from -5.00D to -9.00D, and the astigmatic diopter was range from -1.00D to -3.00D. The following-up period was for 6 months. The outcome of astigmatism correction was evaluated by the standardized vector analysis which was recommended by the American National Standards Institute. The photopic without glare CSF with best spectacle-corrected visual acuity was examined by CSV-1000E. RESULTS: The CSF of all spatial frequency in 1 month postoperatively were significant lower than that preoperatively(PPPr=0.537, 0.674, PCONCLUSION: There was decrease in high spatial frequency contrast sensitivity under photopic without glare of myopic and astigmatic eyes with midrange and high diopter within 6 months after Epi-LASIK. The SIRC might have correlation with the decrease in contrast sensitivity.

Keywords

• vector analysis
• astigmatism
• epipolis laser <i>in situ</i> keratomileusis
• contrast sensitivity