Infra-red transillumination stereophotography of the iris in Fuchs's heterochromic cyclitis.

The structural pattern of the iris in 13 patients with Fuchs's heterochromic cyclitis (FHC) was studied by infra-red transillumination stereophotography. All eyes with FHC showed atrophic changes of the iris. Extensive iris atrophy appeared as light, even translucence of the iris, associated in some cases with occasional dense small patches or pigment clumps. Moderate punctate, patchy or radiate, or extensive atrophy of the sphincter muscle was seen in all eyes with FHC. Radial contraction folds of Schwalbe, structural folds of Schwalbe, and circular contraction folds on the posterior surface of the iris were visualised in few eyes with FHC, whereas they were seen in most contralateral eyes. The results suggest that infra-red transillumination sterophotography can be used as a diagnostic method in FHC.