Accelerated corneal collagen cross-linking treatment for keratoconus: a one year analysis

Session Details

Session Title: Cross-Linking Protocols

Session Date/Time: Monday 24/09/2018 | 14:00-16:00

Paper Time: 15:26

Venue: Room A3, Podium 3

First Author: : Y.Chen UK

Co Author(s): :    R. Rana-Rahman   D. Ting   J. Danjoux   S. Morgan   S. Ghosh   O. Baylis     

Abstract Details

Purpose:

Collagen crosslinking (CXL) has emerged as the standard of care for progressive keratoconus over the last decade. The traditional protocol involves 30 minutes of riboflavin instillation followed by 30 minutes of ultraviolet-A (UVA) illumination at 3 mW/cm2. This lengthy duration requirement has encouraged the development of accelerated CXL protocols as an alternative technique, where higher energy settings are used to permit a shortening of the overall exposure time while maintaining the total radiant exposure. This study aims to examine the long-term efficacy and safety data one year following accelerated CXL and to analyse risk factors associated with progression post treatment.

Setting:

Sunderland Eye Infirmary - single tertiary referral centre in the UK

Methods:

Retrospective case series review of 53 eyes of 51 patients with progressive keratoconus. All patients underwent accelerated cross-linking using an UVA exposure with energy release of 9 mW/cm2 for 10 minutes, between January 2015 and December 2016. All patients had a minimum of 12 months follow up post CXL treatment. Best corrected visual acuity (BCVA), corneal topography measurements including the maximum K (K max), K mean and corneal astigmatism were evaluated preoperatively then at 6 months and 12 months postoperatively.

Results:

Thirty-two male and 19 female patients were included, mean age 24.4±6.8 years. Fifty-one (93%) patients maintained or improved their vision (<2-line loss). From preoperative to 1-year postoperative, there were non-significant improvements in Kmax (60.5±7.35 D vs. 59.45±7.31 D; p=0.55), Kmean (49.2±4.59 vs. 49.1±4.45 D; p=0.94) and astigmatism (3.29±1.86 D vs. 2.95±2.45 D; p=0.43). There were 5 (9.1%) cases of corneal haze post CXL, which settled by 6 months postoperatively. Negative prognostic factors for significant post-treatment progression of keratoconus included preoperative Kmax>57D (p=0.015), preoperative Kmean>48D (p=0.005), and >1D change in Kmax from preoperative to 6 months post-CXL (p=0.001).

Conclusions:

Our study demonstrates the long-term effectiveness and safety of accelerated CXL on halting the progression of keratoconus, and the prognostic factors associated with progression post CXL. Accelerated CXL may provide more stabilising effect on the milder form of keratoconus, highlighting the potential benefit of early treatment. Large prospective randomised controlled trials with longer term follow up is required to evaluate whether accelerated CXL is superior to the traditional protocol.

Financial Disclosure:

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