Outcomes of excimer laser surface ablation prior to, simultaneously or after cross-linking in keratoconic eyes

Session Details

Session Title: Cross-Linking

Session Date/Time: Tuesday 10/10/2017 | 14:00-16:30

Paper Time: 14:18

Venue: Room 4.6

First Author: : A.Bardan UK

Co Author(s): :    D. Healy   M. Nanavaty                 

Abstract Details

Purpose:

To evaluate the outcomes of Excimer laser surface ablation (ELSA) prior to, simultaneously or after crosslinking (CXL) in keratoconus corneas.

Setting:

literature review of 23 studies published on pubmed on ELSA and CXL use in keratoconus and comparison of results of simultaneous and sequential protocols. Inclusion criteria were, at least 20 eyes, 12 months follow-up and proven diagnosis of keratoconus. Exclusion criteria, studies on post laser surgery ectasia, Pellucid Marginal degeneration.

Methods:

Studies with epithelial on and off, conventional and rapid CXL were included. The data was further divided into 3 broad categories: studies with CXL followed by sequential ELSA (Category 1) n=3; simultaneous ELSA and CXL (Category 2) n=13 and ELSA followed by CXL (Category 3) n=7. Data on pre and postoperative LogMAR uncorrected (UCVA) and best corrected visual acuity (BCVA), manifest refraction, maximum keratometry (Kmax), thinnest local pachymetry, complications, progression, need for glasses or contact lenses and any additional procedures within 1 year of primary procedure were noted.

Results:

In category 1, the logMAR UCVA and BCVA improved from 0.92±0.38 to 0.41±0.27 and from 0.38±0.24 to 0.15±0.20 respectively, mean spherical equivalent (SEQ) improved by 2.37 D, mean Kmax decreased by 2.70 D. In category 2, the mean UCVA improved from 0.59±0.29 to 0.30±0.22, BCVA improved from 0.32±0.21 to 0.28±0.14, mean SEQ improvement was 1.54 D, mean Kmax decreased by 2.97 D. In category 3, the mean UCVA improved from 0.64 to 0.09, mean BCVA improved from 0.05 to 0.03, mean SEQ improvement was 2.69 D, mean Kmax decreased by 1.91 D.

Conclusions:

Simultaneous ELSA and CXL showed more improvement in BCVA, whereas ELSA followed by CXL showed more improvement in SEQ. CXL followed by ELSA showed maximum reduction of pachymetry. Only one study with ELSA followed by CXL reported progression post procedures. There remains a clear uncertainty on which protocol is better and larger scale comparative trials are required.

Financial Disclosure:

NONE