Abstract
Purpose: :
To determine the usefulness of multifocal electroretinography (mfERG) in the evaluation of patients with uveitis whose visual loss is not explained by findings on clinical examination and optical coherence tomography (OCT).
Methods: :
Retrospective, consecutive, non-comparative case series. Patients with a history of uveitis, visual loss > 1 mo not explained by clinical findings, and without evidence of cystoid macular edema on OCT (STRATUS OCT, Carl Zeiss MicroImaging, Thornwood, NY) underwent mfERG with the VERIS system (Electro-Diagnostic Imaging, San Mateo, CA). The trace array for the first-order kernel component and the three-dimensional response density topography were evaluated for central depression. Center point thickness was determined by OCT.
Results: :
Fourteen eyes of seven patients (5 females, 2 males) with mean age 37.3 years (range 19 - 64) were evaluated. Ten eyes demonstrated unexplained visual loss, with visual acuity ranging from 20/40 - 20/400. Diagnoses included pars planitis (n=5 eyes of 4 patients), anti-retinal antibodies (n=2 eyes of 1 patient), anti-retinal antibodies and sarcoidosis (n=2 eyes of 1 patient), and retinal vasculitis of unclear etiology (n=1). No eyes with visual loss demonstrated cystoid macular edema on OCT at the time of mfERG. The mean center point thickness was 225 microns (range 205 microns - 251 microns). All ten eyes with visual loss had marked central depression on both the first-order kernel trace array and three-dimensional response density topography. Unaffected fellow eyes of patients with unilateral disease did not demonstrate any mfERG abnormalities.
Conclusions: :
The central depression in mfERG of eyes with visual loss suggests that inflammation has led to dysfunction of the outer retinal layers that was not demonstrable by clinical examination or OCT. This suggests a role for mfERG in the evaluation of unexplained visual loss in patients with uveitis.
Keywords: electroretinography: clinical • macula/fovea