ESCRS - FPS02.02 - Evaluation Of Corneal Parameters For The Progression Of Keratoconus

Evaluation Of Corneal Parameters For The Progression Of Keratoconus

Published 2022 - 40th Congress of the ESCRS

Reference: FPS02.02 | Type: Free paper

Authors: Dharshana Ramanathan* 1 , Zahra Ashena 1 , Shaira Doherty 1 , Akilesh Gokul 2 , Charles McGhee 2 , Mohammed Ziaei 2 , Mayank Nanavaty 1

1Ophthalmology,Sussex Eye Hospital,Brighton,United Kingdom, 2Ophthalmology,The University of Auckland,Auckland,New Zealand

Purpose

Corneal topography is an important tool in the detection and progression of ectatic changes. Several parameters have been argued as being more superior in evaluating the progression of keratoconus. A recent multicentre study suggested mean corneal power in the steepest meridian (K2) to be the most useful parameter for progress compared to maximum anterior sagittal curvature (Kmax). To study this further, we evaluated if keratoconus progression is best monitored through the assessment of K2 versus Kmax following crosslinking for keratoconus.

Setting

Sussex Eye Hospital, University Hospitals Sussex NHS Foundation Trust, Brighton. United Kingdom.

Methods

A retrospective analysis was performed of 201 eyes that had undergone crosslinking at two centres (Sussex Eye Hospital, University Hospitals Sussex NHS Foundation Trust, Brighton & Department of Ophthalmology, University of Auckland, New Zealand). All patients had computerised corneal topography using the Pentacam HR® pre-operatively and at 12 months. Primary outcome measure: mean difference in K2 vs mean difference in Kmax at 0 and 12 months. Secondary outcome measures: Apical corneal thickness.

Results

The mean K2 pre-operatively was 51.0 D ± 5.22 and at 12 months 50.0 D ± 5.00 (p=0.00). Mean Kmax was 58.0 D ± 7.66 pre-operatively and 57.0D ± 7.50 at 12 months (p=0.00). The mean difference in K2 pre-operatively and at 12 months was 0.42 ±1.22 (95% CI [0.37, 0.48]) and of Kmax 1.02±1.74 (95% CI [0.94, 1.10] (p=0.00). Mean apical corneal thickness pre-operatively was 461µm ±38 and at 12 months, 454µm ±40 (p=0.00).

Conclusions

Our results show that the Kmax difference is higher with a wider 95% confidence interval post-operatively compared to K2. Therefore, Kmax is likely to pick up progression earlier than K2, making an evaluation of Kmax better than K2 for the assessment of keratoconus.