Subretinal Deposits and Abnormal ERG Findings in Extensive Macular Atrophy With Pseudodrusen-Like Appearance (EMAP)

Abstract

Purpose: : Extensive Macular Atrophy with Pseudodrusen-like appearance (EMAP) occurs in middle-aged patients and rapidly leads to legal blindness. Pathophysiology of this disease is unknown. We sought to explore the retinal function in EMAP patients and to localize the pseudodrusen.

Methods: : Prospective spectral domain OCT and electrophysiological study. Eighteen patients with an EMAP retinal disease were re-examined and underwent a second full-field ERG following the ISCEV guidelines except for a prolonged 2-hour dark adaptation time. The macular area was re-analysed using a spectral domain optical coherent tomography (Heidelberg Spectralis) including a point to point correlation to the combined near infrared frames.

Results: : Spectralis OCT findings:

Conclusions: : These results suggest that in EMAP, unlike in atrophic AMD, there is a major rod dysfunction without significant cell death. Rod impairment could be linked to the diffuse subretinal deposits located between the retinal pigment epithelium and the outer segments of the photoreceptors, thus delaying regeneration of the visual pigment.

Keywords: macula/fovea • electrophysiology: clinical • degenerations/dystrophies