Abstract
Purpose:
Congenital aniridia consists in a complex malformation of the eye with congenital absence of iris. This genetic rare disease can cause severe visual impairment occurring from various mechanisms as glaucoma, limbal insufficiency and foveal hypoplasia. PAX6 gene is involved in the disease. The aim of the study is to describe iridocorneal angle with anterior segment imaging analysis and to evaluate glaucoma in congenital aniridia patients.
Methods:
Retrospective study of 22 congenital aniridia patients, range 2 to 61 years-old.They were evaluated with a complete ocular examination. Patients had an anterior segment analysis with Scheimpflug imaging (Pentacam) and Visante OCT. Also was performed corneal topography, non contact pachymetry and macular OCT. All images were recorded and analysed to measure the angle and evaluate iris aplasia or hypoplasia.
Results:
Of the 22 aniridia patients, OCT Visante and Scheimpflug imaging appreciated iris aplasia or hypoplasia. Fifteen presented an iris stub complicated of a glaucoma in 7 cases (47%) and 12 presented a treated glaucoma (54.5%). Of the twelve patients with glaucoma, 5 had no iris stub visible to Visante OCT (41%). Of the 7 patients with no iris stub, 5 presented a glaucoma (71%). The twelve patients were 20 years-old or more and 9 patients presented a bilateral glaucoma (75%).Central pachymetry measurements were evaluated for 16 patients and 14 presented a corneal thickness superior to 600 microns.
Conclusions:
Congenital aniridia is a panocular disease with developmental abnormalities, limbal stem cell deficiency and trabeculum dysgenesia. Risk factor of glaucoma in aniridic eye is a common complication difficult to evaluate precisely and an evaluation of central cornea meets a an increase thickness and allows to estimate the exact ocular pressure. Specific anterior segment analysis is required for the follow-up of aniridia patients in order to get a better evaluation of glaucoma risks and treatment.