Peripheral pigmented lesions in Stargardt disease

Abstract

Purpose : Stargardt disease (STGD) is caused by pathogenic variants in the ABCA4 gene and has characteristic fundus findings such as macular atrophy and flecks at the posterior pole, which tend to extend peripherally. Fundus autofluorescence (FAF) has proven to be valuable tool in the diagnosis and surveillance of this condition. Standard 30⁰ field imaging is generally utilized with these patients, however limiting evaluation to the posterior pole. Using wide-field fundus photography (WF-P) and wide-field fundus autofluorescence (WF-FAF), we studied peripheral retinal changes in patients with mutation-proven Stargardt disease.

Methods : A retrospective chart review was performed for patients with a clinical diagnosis of STGD and with two or more variants in the ABCA4 gene that were classified by the genetic testing lab as either pathogenic or likely pathogenic. We excluded patients without WF-P, defined as either Optos 200^o retinal imaging (Optos 200 Tx, Optos PLC, Dunefermline, United Kingdom) or composites of 50^o fundus photographs. Age of symptoms, disease duration, full-field electroretinogram (ffERG) and WF-FAF were examined.

Results : Of 145 patients with a molecular diagnosis of SGDT, 97 had WF imaging. Among those, 12 (12.37%) presented with peripheral pigmented retinal lesions. All patients presented with early-onset disease (mean age 9.33 years, range 7-13), with mean disease duration of 16 years (range 6-29). 53.8% were female. Rod-cone loss on ERG was observed in 91.3%. On WF-P, all peripheral lesions were pigmented, and on WF-FAF, most lesions were hypoautofluorescent, except for a newly formed one that was hyperautofluorescent with some mottled hypoautofluorescence in the center. In 6 patients with follow-up images, 4 showed growth of those lesions including one patient who developed new lesions.

Conclusions : Pigmented peripheral lesions may occur in patients with early-onset STGD, seem to be acquired and may progress. These lesions mostly present as hypoautofluorescent lesions on FAF, although in early stages might be hyperautofluorescent. These lesions can be mistaken for congenital hypertrophy of retinal pigment epithelium. .

This is an abstract that was submitted for the 2017 ARVO Annual Meeting, held in Baltimore, MD, May 7-11, 2017.

 

Upper: baseline WF-P showing peripheral retinal pigmented lesions in the left eye. Lower: follow-up showing newly developed lesions in both eyed and growth of pre- existent lesion.

 

WF-FAF showing both hypo and hyperautofluorescent lesions compatible with the lesions seem on WF-P.