Prospective 2 year study of changes in corneal density following corneal collagen cross-linking for keratoconus

Session Details

Session Title: Presented Poster Session: Cross-Linking

Venue: Poster Village: Pod 2

First Author: : M.Ziaei NEW ZEALAND

Co Author(s): :    A. Gokul   H. Vellara   J. Meyer   D. Patel   C. McGhee           

Abstract Details

Purpose:

To compare the corneal densitometry changes after transepithelial (t-ACXL), epithelium-off continuous (c-ACXL) and epithelium-off pulsed (p-ACXL), accelerated corneal collagen crosslinking for patients with progressive keratoconus.

Setting:

University hospital tertiary referral center.

Methods:

Prospective, interventional case series. Seventy-three patients with progressive keratoconus were included. Three groups of eyes received treatment; 33 eyes received t-ACXL with pulsed illumination using 45 mW/cm2 for 5 minutes and 20 seconds for a surface dose of 7.2 Jcm2, 20 eyes received c-ACXL at 30 mW/cm2 for 4 minutes for a surface dose of 7.2 J/cm2 and 20 eyes received p-ACXL at 30 mW/cm2 for 8 minutes (1 sec. on/1 sec. off) for a surface dose of 7.2 J/cm2. Corneal tomography, densitometry, corrected and uncorrected distance visual acuity were evaluated preoperatively and up to 24 months postoperatively.

Results:

Total densitometry values of the total layer over the annular diameters 0 to 12mm showed no significant change after t-ACXL and p-ACXL but increased significantly after c-ACXL at 1month (16.76±2.38, P value <0.01) and 3 months (16.12±2.22, P value 0.04), returning to baseline levels at month 6 (14.97±2.13, P value 0.99) and remained stable until final followup. At 1 month, the mean change in total densitometry value of the t-ACXL group (-0.53±2.08) was significantly lower than the p-ACXL (0.70±1.96 P value 0.04) and c-ACXL (1.97±2.65 P value <0.01).

Conclusions:

Continuous epithelium-off accelerated cornea crosslinking appears to induce more corneal haze than pulsed epithelium off and transepithelial cornea crosslinking in the early postoperative period. Differences resolve by six-months.

Financial Disclosure:

None