[Bietti's crystalline retinopathy].

The authors previously reported four cases with crystalline retinopathy and suggested that it be classified into three stages: 1) retinal pigment epithelium (RPE) atrophy in the posterior pole, 2) choriocapillaris atrophy appearing in the enlarged areas of RPE atrophy, and 3) prominent diffuse atrophy of both the RPE and choriocapillaris. We followed up 4 cases, including 2 cases which were previously been reported, and have now evaluated the clinical features of this disease. The results indicated that the above classification was clinically useful. Enlargement of the RPE atrophy from stage 2 to 3 was due to enlargement and confluence of the RPE atrophy between the posterior pole and the periphery. In addition, disturbances in ERG and color vision were thought to correlate with secondary dysfunction at the level of the photoreceptor cell layer within the diseased lesions.