Posters

Evaluation of visual performance in keratoconic patients undergoing simultaneous conventional photorefractive keratectomy followed by corneal cross-linking

Poster Details

First Author: A.Plaka GREECE

Co Author(s):    N. Tsakalis   G. Kontadakis   S. Plainis   H. Ginis   G. Kymionis  

Abstract Details

Purpose:

To evaluate visual performance in keratoconic patients undergoing simultaneous conventional photorefractive keratectomy (PRK) followed by corneal crosslinking (CXL)

Setting:

Institute of Vision and Optics, University of Crete

Methods:

Prospective, interventional, case series. 15 patients (18 eyes) with progressive keratoconus were included. There was performed preoperative and postoperative evaluation of retinal straylight (C-Quant, Oculus GmbH) for two eccentricities (7o and 3,5o), cycloplegic manifest refraction with 6 mm artificial pupil, monocular and binocular cycloplegic corrected ETDRS visual acuity with 3 and 6 mm artificial pupil, cycloplegic contrast sensitivity assessment in a dark room (FΑCT, Vision Sciences Research Corp.) using an 6 mm artificial pupil and cycloplegic wavefront analysis for 3 and 6 mm pupil (iTrace; Tracey Tech, Houston, Texas, USA)

Results:

Preoperatively mean retinal straylight value at 7ο was 1.06 ± 0.26 log units and at 3.5ο 1.198 ± 0.15 log units. Postoperatively mean retinal straylight value increased to 1.13 ± 0.11 log units at 7ο (p=0.26) and at 1.338 ± 0.12 log units at 3.5ο (p=0.04). Visual acuity improved at the statistical significant level of 5%. Contrast sensitivity improved postoperatively at all spatial frequencies in mesopic and photopic conditions. RMS values of total, low and high order aberrations as well as 3rd order aberrations, coma, defocus and astigmatism show significant reduction.

Conclusions:

Combined photorefractive keratectomy and corneal crosslinking seem to result in better visual performance by improving corrected visual acuity and contrast sensitivity as well as by reducing visual impairment caused by aberrations. Retinal straylight is increased due to corneal structural changes and posterior haze formation. Further follow-up and additional cases are needed in order to obtain final conclusions regarding visual performance of keratoconic patients after combined treatment. FINANCIAL DISCLOUSRE: NONE