Quantitative analysis of iris translucency in Fuchs' heterochromic cyclitis

Abstract

Purpose: To measure intraocular stray light and to quantify translucency of the iris and the surrounding ocular wall in both eyes of patients with Fuchs' heterochromic cyclitis; to investigate whether differences in paired eyes could be measured in patients without heterochromia or with a minimal degree of iris atrophy.

Methods: Intraocular stray light was measured by means of the direct compensation technique. A modification of this technique was used to quantify translucency of the iris and the surrounding ocular wall.

Results: Intraocular stray light proved to be significantly higher in all patients with Fuchs' heterochromic cyclitis (both eyes) than in normal control subjects. Translucency of the iris and the ocular wall around it were increased in the patients with Fuchs' heterochromic cyclitis, including patients without heterochromia or with a minimal degree of iris atrophy.

Conclusions: Quantitative analysis of translucency was used to determine iris depigmentation in vivo in patients with Fuchs' heterochromic cyclitis. This technique showed that the process of atrophy and depigmentation in patients with Fuchs' heterochromic cyclitis is probably not restricted to the iris, but also occurs in the surrounding ocular wall. More studies, including other uveitis groups, are necessary to investigate if this technique can be used as a diagnostic tool in Fuchs' heterochromic cyclitis.