Chorioretinal scars in Fuchs' heterochromic iridocyclitis.

To determine the incidence of chorioretinal lesions in patients with Fuchs' heterochromic iridocyclitis, we reviewed the records of all patients with this disease seen at the Indiana University Uveitis Service, Indianapolis, since 1963. For comparison the records of age- and sex-matched patients with HLA-B27-positive iritis were also reviewed. The incidence of chorioretinal lesions in one or both eyes of patients with Fuchs' heterochromic iridocyclitis was significantly higher than in the patients with HLA-B27-positive iritis or than expected in the general population. Among the types of lesions manifested, the most notable increase was in toxoplasmosislike lesions. However, two of the five patients with these lesions had negative indirect hemagglutination assays for toxoplasmosis, down to undiluted serum. The reason for the high incidence of chorioretinal lesions in patients with Fuchs' heterochromic iridocyclitis is unclear and may be related to immunologic changes in these patients.