Fuchs' heterochromic cyclitis is characterized by a chronic, low-grade non-granulomatous anterior uveitis with widely scattered small keratic precipitates, a variable degree of atrophy and depigmentation of the iris, and no synechiae. It is usually unilateral, although bilateral involvement has been reported in up to 10 % of cases. Fuchs' heterochromic cyclitis occurs in approximately 5 % of all patients with uveitis and is regarded as a distinct nosological entity. The typical age of onset is in the third or fourth decade, and there is an equal incidence among men and women. Because not all characteristic clinical signs are present at the same time, the diagnosis of Fuchs' heterochromic cyclitis is often difficult to make, especially in the earlier stages of the disease. No minimal clinical diagnostic criteria, pathognomonic for this eye disease, have been internationally accepted yet, and no laboratory tests are available to confirm the diagnosis of Fuchs' heterochromic cyclitis. Fuchs' heterochromic cyclitis may even be considered as the most commonly misdiagnosed form of uveitis. Cataract and glaucoma are two major complications in Fuchs' heterochromic cyclitis. A subcapsular cataract develops in almost all cases, whereas glaucoma occurs in approximately 20 % of the cases. Cataract extractions with or without intraocular lens implantation currently have excellent results. Glaucoma is considered to be the most serious complication, because the therapy of glaucoma (medical and surgical), as reported in the literature, has a poor outcome. The origin of Fuchs' heterochromic cyclitis is still unknown and many hypotheses for the etiology of this eye disease have been proposed since Ernst Fuchs presented his theory in 1906. In chronological order, these theories are the following: Sympathetic Theory, Hereditary Theory, Association with Toxoplasmosis, Vascular Theory and Immunologic Theory. Until now. no definite proof has been obtained to accept or to reject any of these theories. AIM OF THE THESIS The aim of this thesis was to study the clinical aspects and etiology of Fuchs' heterochromic cyclitis. An update of the literature on Fuchs' heterochromic cyclitis is presented in chapter 2. Clinical Aspects Based on an analysis of clinical findings in 51 patients, clinical diagnostic criteria for Fuchs' heterochromic cyclitis are proposed in chapter 3. In chapter 4, the severity and prognosis{ of secondary glaucoma are evaluated, based on a larger series of patients with Fuchs' heterochromic cyclitis who needed medical and surgical intervention for glaucoma. Iris translucency, an important clinical feature, is quantified in patients with Fuchs' heterochromic cyclitis by a modification of the direct compensation technique for the measurement of intraocular stray light in chapter 5. Etiology Different approaches have been used to study the various etiological theories on Fuchs' heterochromic cyclitis. One case report and a short review of the literature to support the sympathetic theory and the association between Fuchs' heterochromic cyclitis and the Parry Romberg syndrome are presented in chapter 6. Two cases with Fuchs' heterochromic cyclitis and a definite (congenital) ocular toxoplasmosis (chapter 7 and 8), and clinical and laboratory examinations for ocular toxoplasmosis in a larger series of patients with Fuchs' heterochromic cyclitis (chapter 9) are reported to elucidate the association between Fuchs' heterochromic cyclitis and toxoplasmosis-like chorioretinal lesions. The alternative hypothesis for the chorioretinal lesions in Fuchs' heterochromic cyclitis, namely that of autoimmunity directed against retinal antigens, was evaluated in chapter 10. Chapter 11 describes the detection of circulating autoantibodies against the anterior segment (uvea, cornea) of the eye in patients with Fuchs' heterochromic cyclitis. In chapter 12 the hypothesis of an immune complex vasculitis of the iris vessels was assessed with an immunofluorescence technique on peripheral iridectomies of patients with Fuchs' heterochromic cyclitis.

Uveitis, cataract, glaucoma, ophthalmology
P.T.V.M. de Jong (Paulus) , A. Kijlstra Prof. Dr
Erasmus University Rotterdam
Erasmus MC: University Medical Center Rotterdam

La Heij, E.C. (1993, November 3). Clinical aspects and etiology of Fuchs' heterochromic cyclitisKlinische aspecten en etiologie van de heterochrome cyclitis van Fuchs. Erasmus University Rotterdam. Retrieved from http://hdl.handle.net/1765/38451