High Order Aberration Outcomes of Corneal Collagen Crosslinking in Eyes with Keratoconus and Post-LASIK Ectasia

Abstract

ABSTRACT Purpose To evaluate the effect of riboflavin and ultraviolet- A-induced corneal collagen crosslinking (CXL) on high order aberrations (HOA) up to third-order at 6 months using the iTrace wavefront aberrometer in patients with progressive keratoconus and post-LASIK ectasia. Materials and methods Ongoing retrospective chart review of patients having undergone CXL. The iTrace (Tracey Technologies, Houston, TX) was used to evaluate HOA. Patient data was collected from a single clinical site pre- and 6 months postoperatively. Data collected included logMAR uncorrected distance visual acuity (UDVA), logMAR corrected distance visual acuity (CDVA), manifest refraction, and HOA measurements. Data was analyzed with paired two-tailed student's t-test. Results 18 eyes (9M:4F, mean age 29.2 years, range 16-45) had 6 months of follow-up. Total HOAs, total coma and total trefoil were significantly reduced at 6 months by 16, 33 and 26% respectively (p < 0.05). Nonsignificant trends toward improvement were seen in spherical aberration, secondary astigmatism and UDVA. There were no statistically significant changes in manifest refraction or CDVA. Conclusion Improvement in high order aberration profile is one mechanism by which corneal collagen crosslinking enhances visual function in ectatic corneas. Total HOA and total coma measures are the most commonly reported improvements in HOA measures in previous studies, while total trefoil has only been observed in one other study. The improvements seen in HOAs remain fairly modest which likely accounts for the lack of measureable improvement in high-contrast visual acuity measures, such as Snellen UDVA and CDVA. This study is the first to report HOA outcomes with the iTrace wavefront aberrometer. How to cite this article Muzychuk A, Penner V, Rocha G. High Order Aberration Outcomes of Corneal Collagen Crosslinking in Eyes with Keratoconus and Post-LASIK Ectasia. Int J Kerat Ect Cor Dis 2014;3(3):107-112.