Progressive Fundus Autofluorescence Patterns in Achromatopsia

Abstract

Purpose: To describe the progression of fundus autofluorescence (FAF) patterns in patients with achromatopsia and the associated findings on optical coherence tomography (OCT).

Methods: A restrospective review was conducted of eight patients with achromatopsia caused by mutations in CNGA3 or CNGB3. Patients were evaluated with best-corrected visual acuity (BCVA), ophthalmoscopy, Goldmann visual field (GVF), OCT, full-field electroretinography (ffERG), and FAF photography. FAF patterns were compared and correlated with patient age and foveal changes on OCT.

Results: Patients fell into two dichotomous age groups at the time of evaluation, with 5 patients ranging from 11 to 23 years old and 3 patients ranging from 52 to 63 years old. All patients had severely reduced photopic ffERG parameters. The younger patients had mild to no foveal atrophy on OCT, and four out of five demonstrated focal foveal or parafoveal hyperfluorescence on FAF. In addition, a 7 month-old child with compound heterozygous mutations in CNGA3 demonstrated similar parafoveal hyperfluorescence. The older patients had advanced foveal atrophy with cavitation on OCT, and all three demonstrated punched-out foveal hypofluorescence with discreet borders on FAF imaging.

Conclusions: In our cohort, achromatopsia patients demonstrate a unique pattern of foveal hyperfluoresence with age-dependent progression to foveal hypofluoresence that correlates with outer retinal atrophy and cavitation on OCT. Foveal hyperfluorescence may be an early sign of pathologic change that should prompt further diagnostic testing for achromatopsia. Furthermore, FAF patterns in achromatopsia may be useful in charting the natural course of disease and in defining a therapeutic window for treatment in future investigations.

Keywords: 696 retinal degenerations: hereditary • 539 genetics • 552 imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound)