Central Corneal Thickness in Patients with Congenital Aniridia

Purpose: To compare the mean central corneal thickness (CCT) in patients with congenital aniridia to that of a group of age-matched control subjects. The findings of specular and confocal microscopy in a patient with aniridia are discussed.

Methods: The mean values of five consecutive pachymetry measurements of patients with aniridia and control subjects were used for analysis. Statistical analysis was performed with a Mann-Whitney rank sum test. Specular microscopy was performed on one patient with aniridia using a Konan Specular Microscope Noncon ROBO CA (Hyogo, Japan). Confocal microscopy through focusing was performed with the Tandem Scanning Confocal Microscope (Reston, VA).

Results: Mean CCT measured 691.8 +/- 75.4 mum for patients with aniridia (16 eyes of 10 patients) and 548.2 +/- 21.2 mum for control subjects (P < 0.001). Specular microscopy in a patient with aniridia showed normal endothelial cell counts and structure. Confocal microscopy through focusing of this patient showed normal-appearing keratocytes and a thick corneal stroma.

Conclusions: Patients with congenital aniridia have significantly thicker corneas than do age-matched control subjects. This difference can have important implications for the treatment of those patients who develop secondary glaucoma. The increased CCT in patients with aniridia is not a result of endothelial dysfunction but appears to be the result of the production of a thickened but otherwise healthy cornea by the mutated PAX6 gene.