Posters

Corneal collagen cross-linking for extreme keratoconus with ultra-thin corneas: three year follow-up

Poster Details

First Author: J.Frucht-Pery ISRAEL

Co Author(s):    B. Rosin   D. Landau   E. Strassman   S. Frenkel   D. Wajnsztajn  

Abstract Details

Purpose:

To report the 3 year outcomes of standard corneal collagen crosslinking (CXL) treatment for keratoconus (KC) in corneas thinner than 400μm pre-epithelium abrasion.

Setting:

Hadassah Medical Center - Hebrew University Hospital, Ophthalmology Department, Jerusalem, Israel

Methods:

We retrospectively reviewed all files of patients with corneas thinner than 400μm who had CXL for KC (August 2007 to March 2013). Principal outcomes were best corrected visual acuity (BCVA, in LogMAR), topography derived maximum keratometry (Kmax), topographic cylinder, mean keratometry (mean K, central 3mm zone) during the first 3 years post-CXL. Procedures were done using Dresden protocol with hypotonic riboflavin (UV-X &trade Specifications, IROC, Zurich, Switzerland). Statistical analysis was performed by Wilcoxon Rank Sum Test using Matlab 2013b, The Mathworks Inc, Natick MA.

Results:

Forty four eyes of 38 patients (30 males) aged 24.6±6.6 yrs (range: 11-40 yrs) had CXL for KC in corneas thinner than 400μm pre-treatment (mean 368.6±20.8 μm, range: 316-399μm). After abrasion and application of hypotonic riboflavin, mean pachymetry was 448.7±50.8μm (378-575μm). After 1 year (n=42 eyes) Kmax, mean K, topographic cylinder, and BCVA changed from 62.4±4.9D to 59.5±4.9D (p = 0.0121), from 57±4.8D to 55.2±5D (p=0.1472), from 3.75±2.2D to 3.05±1.5D (p= 0.2374) and 0.46±0.3 to 0.43±0.26 (p=0.86) respectively. After 2 years (n=24 eyes) Kmax, mean K, topographic cylinder, and BCVA changed from 61.9±4.5D to 58.4±5.7D (p=0.0328), from 56.9±5.1D to 54.4±5.3D (p=0.0928), from 3.77±2.2D to 3.13±2D (p=0.0928) and 0.41±0.2 to 0.4±0.2 (p=0.8584) respectively. After 3 years (n=6 eyes) Kmax, mean K, topographic cylinder, and BCVA changed from 61.8±3.6D to 55.25±6.6D (p=0.0931), from 55.6±5D to 51.5±6.3D (p=0.1797), from 4.47±3.2D to 3.2±1.3D (p=0.5087) and 0.35±0.3 to 0.4±0.2 (p= 0.9714) respectively. Two eyes lost 2 lines and 2 eyes lost 3 lines of BCVA. Nine eyes had epithelium delayed healing, 2 eyes had sterile contact lens-related infiltrates and 1 eye had microbial keratitis. Two eyes had mild haze.

Conclusions:

CXL is an efficacious treatment for very advanced KC with thin corneas. However, post-operative complications are common in this group of patients. FINANCIAL INTEREST: NONE