Correlation of in-vivo confocal microscopy (IVCM) findings with clinical severity of aniridia-related keratopathy (ARK)

Session Details

Session Title: Presented Poster Session: Cornea – Medical

Session Date/Time: Saturday 05/09/2015 | 09:30-11:00

Paper Time: 10:20

Venue: Poster Village: Pod 4

First Author: : N.Mandal UK

Co Author(s): :    A. Shortt              

Abstract Details

Purpose:

The aim of this study was to determine whether the clinical signs of ARK correlate with changes in the corneal epithelium, anterior stromal keratocyte population and sub-epithelial nerve plexus observed using IVCM.

Setting:

Cornea and External Disease Service, Moorfields Eye Hospital NHS Foundation Trust, London UK. Department of Ocular Biology and Therapeutics, UCL Institute of Ophthalmology, London UK

Methods:

3 normal subjects and 8 patients with ARK of varying degrees of severity were prospectively recruited. Clinical photographs all corneas were graded using the Clinical Outcome Assessment in Surgical Trials of Limbal stem cell deficiency (COASTL) tool developed by our group. Corneal epithelial haze, superficial corneal neovascularisation and corneal epithelial irregularity was graded from 0 (normal) to grade 3 (severe) and then summated to give a score of overall severity. IVCM volume scans were performed to obtain average corneal basal epithelial cell density (cells/mm2), average anterior stromal keratocyte cell density (cells/mm2) and describe the morphological characteristics for each patient.

Results:

Mean(±SD) and median COASTL scores=4.27(±2.3) and 6.5 respectively. All controls COASTL score=0. Mean density of both basal epithelial cells and of anterior stromal keratocytes was significantly lower in aniridia patients than in controls. There was a negative correlation between basal epithelial cell density and COASTL scores from both normal and aniridic patients (N=7, Pearson's correlation co-efficient=-0.79, r squared=0.58, p<0.05). There was a negative correlation between anterior stromal keratocyte density and COASTL scores from both normal and aniridic patients (N=7, Pearson's correlation co-efficient=-0.951, r squared=0.81, p<0.01). Epithelial cell sub-basal nerve morphology and distribution were affected at all levels in aniridic patients.

Conclusions:

Our study supports previous findings of significant reductions in both basal epithelial cell and anterior stromal cell densities in ARK patients when compared to normal controls and that these reductions become greater the more severe the disease. IVCM is a promising tool to identify and evaluate corneal epitheliopathy in aniridia patients and the COASTL grading correlates well with these findings. Our qualitative descriptions also confirm previous findings. We add to the mounting evidence that deficiency of limbal epithelial stem cells is not the primary cause of ARK but rather a secondary phenomenon related to corneal epithelial and keratocyte cell interactions

Financial Interest:

NONE