The Effect of Mitomycin C on Corneal Crosslinking in Keratoconus Patients

Theme: Cornea, external disease & refractive surgery
What: Cornea, external disease & refractive surgery
Part of: Cornea III: Refractive surgery and keratoconus / Cornée III: Refractive surgery and keratoconus
When: 5/31/2024, 04:15 PM - 05:45 PM
Where: Room | Salle 713 AB

Abstract

Purpose: Corneal crosslinking (CXL) is the principal treatment offered for the stabilization of corneal ectatic disorders. Corneal haze commonly develops after CXL and may impact visual acuity outcomes. Mitomycin C (MMC) has been shown to reduce corneal haze following refractive surface ablative procedures. However, the role of MMC in CXL for ectatic disorders needs further evaluation. This study examines the outcomes of MMC application in keratoconus patients undergoing CXL.

Study design: This is a retrospective single-centre study for patients with keratoconus undergoing CXL with or without MMC between January 2021 and June 2022.

Methods: Corneal haze was quantified using Pentacam densitometry values obtained from Scheimpflug images and expressed as grayscale units (GSU). The central zones were analyzed and compartmentalized into the anterior 120-micron depth and total corneal depth. Clinical assessment and topography values were analyzed pre- and post-operatively at 3, 6 and 12 months. Independent and paired samples t tests were performed as appropriate.

Results: Twenty-one eyes of 18 patients were analyzed in each study group. Mean follow-up was 12 months in both groups. Anterior 0-2 mm central densitometry values were similar at baseline between the two groups (mean of 31 in the CXL with MMC group vs 30 in the CXL without MMC group; p=0.8) while they were significantly higher in the CXL with MMC group at 3 months post-operatively (42 vs 36; p=0.03), with no significant change in best-corrected visual acuity. However, there was no significant difference at 6 and 12 months post-operatively (41 vs 39 at 12 months; p=0.8). Baseline pre-operative Kmax and Kmean values were higher in the CXL with MMC group compared to the CXL without MMC group (65D vs 60D for Kmax and 54D vs 49D for Kmean). Kmax values significantly decreased by 2D (p=0.03) in the CXL with MMC group at 1 year post-operatively compared to baseline pre-operatively while Kmax values decreased by 0.4D in the CXL without MMC group. At 1 year, Kmean values decreased by an average of 1D in both groups. Pachymetry measurements remained stable in both groups.

Conclusions: MMC use with CXL for keratoconus patients may result in a transient increase in early post-operative haze with no impact on visual acuity. The increased corneal flattening effect observed with MMC may be partially due to the steeper corneal measurements at baseline in the MMC group and should be explored further in future studies.

Presenter(s)

Presenting Author: Jack Mouhanna

Additional Author(s):

Johanna Choremis, University of Montreal, McGill Univeristy

Michael Mina, University of Montreal

Reem Alnabulsi, University of Montreal

Isabelle Brunette, University of Montreal

Tanguy Boutin, University of Montreal

Michele Mabon, University of Montreal

Julia Talajic, University of Montreal

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