Corneal changes after collagen crosslinking for keratoconus using dual scheimpflug imaging

Purpose: to evaluate corneal changes after collagen crosslinking (cxl) therapy for keratoconus (kcn) using the galilei dual scheimpflug analyzer. methods: this prospective,nonrandomized clinical study included 35 eyes of 32 keratoconus patients who had undergone cxl. the eyes were saturated with riboflavin solution and were subjected for 30 minutes to ultraviolet-a (uv-a) light with irradiance of 3 mw/cm2. effectiveness of the treatment was assessed by measuring uncorrected visual acuity (ucva),best-corrected visual acuity (bcva),manifest cylinder/sphere,keratometry,pachymetry,posterior and anterior elevations by the galilei dual scheimpflug analyzer. prior to treatment and 8 months after therapy,scheimpflug analysis was performed using the galilei system. the four sets of data including keratometry values,pachymetry,elevation parameters and surface indices were statistically analyzed and compared. results: mean patient age was 22.3 ± 3.8 years and mean postoperative follow-up was 8.1 ± 3.2 months. there was a significant increase in ucva (0.54 ± 0.35 log mar preoperatively to 0.49 ± 0.34 logmar postoperatively,p = 0.01) and bcva (0.21 ± 0.19 log mar preoperatively to 0.16 ± 0.17 logmar postoperatively,p = 0.01). mean cycloplegic spherical equivalent refractive error was -4.13 ± 2.65 diopter (d) preoperatively and - 4.67 ± 2.96 d postoperatively (p < 0.001). during the follow-up period,no significant difference was observed in pachymetric and elevation data postoperatively. conclusion: corneal stabilization could be achieved by collagen crosslinking therapy for keratoconus in terms of corneal thickness,keratometry values,elevation parameters and surface indices. © 2015 journal of ophthalmic and vision research | published by wolters kluwer - medknow.