Clinical and electroretinographic profile of 27 patients with Stargardt disease treated at a hospital in Brazil

Abstract

Purpose: Stargardt disease is the most common type of juvenile-onset macular dystrophy. It is bilateral and symmetrical in appearance, affects the macula, and its main characteristic is the loss of central vision that starts in the first or second decade of life. The purpose of this study was to describe the profile of the patients evaluated at the Complexo Hospital de Clínicas da Universidade Federal do Paraná, as well as describe the electroretinographic findings with the full-field electroretinogram in these patients. Methods: An observational, retrospective study was performed by analysis of records and electroretinographic examinations of 27 patients with Stargardt disease and fundus flavimaculatus who were treated at the Complexo Hospital de Clínicas da Universidade Federal do Paraná’s Department of Ocular Electrophysiology and Neuro-Ophthalmology between 1997 and 2014. The patients included in this study presented clinical features, fundus examination and/or electroretinographic findings compatible with Stargardt disease. Results: The visual acuity in the best eye varied from 0 to 1.6 logMAR (20/20 to 20/800) with an average of 0.89 ± 0.42 logMAR. The age at onset of symptoms varied from since birth to 36 years old (average 19.2 ± 9.2) with the majority of patients having symptom onset in the first or second decade of life. The mean time from the disease’s first symptoms until the diagnosis was 7.3 years. In the fundus examination, every patient presented some kind of abnormality. In the electroretinogram analysis, the majority of patients had results that differed from those of sample controls, i.e., reduced amplitude and increased implicit time in the photopic and scotopic phases. Conclusions: The visual acuity and the age at symptoms onset in this study were compatible with the natural history of this dystrophy. The typical fundus appearance of Stargardt disease and altered electroretinogram were more frequent because of the delay until diagnosis. New prospective studies are necessary to evaluate these patients based on emergent technologies.