Long-term follow-up of Stargardt's disease and fundus flavimaculatus

Abstract

Objective: To understand better the shared characteristics of Stargardt's macular dystrophy (SMD) and fundus flavimaculatus (FF) by reviewing the clinical morphologic and retinal function changes in a large group of affected patients.

Design: The study design was a retrospective case review.

Participants: Fifty-two patients with SMD and 48 patients with FF were observed from 1 to 22 years.

Intervention: Visual acuity (VA), visual fields (VFs), fundus photographs (FPs), fluorescein angiography (FA), electro-oculography (EOG), and electroretinography (ERG) were studied at various intervals.

Main outcome measures: Changes of VA, VF, FP, FA, EOG ratio, and ERG amplitudes and implicit time at different periods in patients with SMD and patients with FF were measured.

Results: Visual acuity decreased gradually in both the SMD and FF groups, and once the 20/200 level was reached, little further change occurred. The yellowish flecks associated with these entities faded with time, and areas of retinal pigment epithelial (RPE) and choriocapillary atrophy developed. In advanced longstanding disease, retinal vessel attenuation and peripheral pigmentary changes were noted. Ninety-four percent of patients with FF were noted to have macular dystrophy at their last visit. Patients who had only central lesions did not have peripheral lesions develop. Intrafamilial variation in the funduscopic pattern was shown in four families. The EOG ratio was abnormal in 2.6% of the patients with SMD and in 48.6% of the patients with FF. An abnormal scotopic ERG was noted in 21.1% of the patients with FF and in none of the patients with SMD. The photopic ERG was abnormal in 32.4% of the patients with FF and in 5.4% of the patients with SMD. In patients with FF, a statistical dependence was noted between the duration of the disease and the ERG results, but no such correlation was seen in the SMD group.

Conclusions: Morphologic changes and retinal function deterioration are more severe in patients with FF than in patients with SMD. The duration of the disease has a greater effect on patients with FF than on patients with SMD. These clinical morphologic and physiologic data may be used to supplement laboratory molecular biologic studies and aid in the further classification of these entities.