Refractive changes after two years accelerated corneal cross-linking in patients with keratoconus

Abstract

Purpose: To describe the visual and topographical changes after accelerated corneal collagen cross-linking (ACXL) in keratoconus-affected eyes. Methods: Clinical records of patients with keratoconus-affected eyes that underwent ACXL treatment and had 24 months of follow-up were reviewed. Data regarding demographics, visual acuity (VA), refraction and Sheimpflug values before and post ACXL were analyzed. We included patients with keratoconus older than 12 years old, with corneal thickness greater than 400 microns and steepest keratometry <60 diopters by Sheimpflug (Pentacam), with reported uncorrected distant visual acuity (UDVA), manifest refraction and best-corrected visual acuity (BCVA) evaluation pre ACXL and 24 months after surgery. The exclusion criteria were: history of ocular trauma, anterior segment surgery, retinal detachment or any type of maculopathy. Results: 21 eyes were included. Mean age was 27 years. Mean uncorrected distant VA (UDVA) before the procedure was 1.01 logMAR (20/200 Snellen) and after 24 months improved significantly to 0.62 logMAR (20/83 Snellen) with a p value of 0.005. No statistical significant difference was found between preoperative and postoperative refractive, keratometric and pachymetric data. Induced astigmatism value was -1.11 D (range 0.13 D – 2.28 D). Conclusions: ACXL is a technique to prevent the progression of keratoconus, however refractive and VA changes could be expected after procedure. The observed changes must be considered when performing the procedure together with refractive surgery.