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Benign retinal vasculitis. Clinical and fluorescein angiographic study.

Central retinal vein occlusion occurs predominantly in the older age groups, and an increased incidence has been reported in association with systemic vascular disease (Paton, Rubinstein, and Smith, I964), chronic simple glaucoma (Smith, 1955), high viscosity syndromes (Rowlands and Vaizey, I938), and malignant disease (Ellis, Hamer, Hunt, Lever, Lever, Peart, and Walker, I 964) . Central retinal vein thrombosis under the age of 40 years is infrequent (Vannas and Raitta, I966), and both clinical (Lyle and Wybar, I96I) and pathological studies (Ballantyne and Michaelson, I947) have suggested an inflammatory aetiology. The appearances in both groups are similar, but the visual loss and retinal changes are less severe in younger patients. The first description (Lyle and Wybar, i96i), comprised six patients whose ages ranged from I4 to 49 years, who had minimal visual symptoms in spite of a florid retinopathy. The process was unilateral in five cases, and after resolution of the retinopathy mild sheathing of the veins and increased vascularity at the disc was seen in three cases. The sixth patient had cells in the anterior chamber in both eyes with a central vein occlusion on one side and a peripheral haemorrhagic retinopathy on the other. Lyle and Wybar postulated that the condition was mainly inflammatory, since the peripheral changes were similar to those of Eales's disease, and suggested the term retinal vasculitis. A further report of five cases (Lonn and Hoyt, I966) substantiated the benign unilateral course of the condition and stressed the absence of inflammatory signs. Cogan (I 969) divided his series into three groups according to the degree of severity and contributed both pathological and aetiological evidence on several cases. This paper presents a clinical and fluorescein angiographic study of nine cases of the syndrome of unilateral central retinal vasculitis occurring in patients under the age of 40 years. Patients with peripheral involvement and vitreous haemorrhages (Eales's disease) were excluded.