Abstract
Purpose :
The mechanism for nutritional amblyopia remains debated, but is thought to be a maculopathy or an optic neuropathy due to an underlying nutritional deficiency necessary for normal functioning of the optic nerve and/or retina. We report mfERG changes in patients with nutritional amblyopia as there is little to no current literature on it with a hope to better understand the underlying electrophysiology changes in patients with nutritional amblyopia.
Methods :
Single center, retrospective chart review of patients diagnosed with nutritional amblyopia with a basic 103 hexagon mfERG performed were isolated. Five patients total with the diagnosis were identified, and four patients who had obtained the above electrophysiology testing were analyzed.
Results :
Four patients with nutritional amblyopia had visual acuities that ranged from 20/40 to 20/200 due to folate deficiency, malabsorption syndrome, and chronic alcohol and tobacco abuse. All four mfERGs performed at the time of diagnosis revealed notable bilateral depressed foveal cone function and depressed amplitudes at the area of the optic nerve head. Three of the four patients exhibited delayed synaptic transduction bilaterally. Two patients who were followed with subsequent mfERGs after initiating nutrition supplementation treatment showed marked improvement of cone depression which correlated with clinical visual acuity. One of the two patients who had a BCVA 20/200 prior to initiating folate treatment improved to 20/25 with treatment initiation and a follow-up mfERG revealed a 42% improvement in foveal peak of mfERG.
Conclusions :
Our electrophysiology findings indicate that the most common mfERG pattern noted in patients with nutritional amblyopia is a foveal depression of the cones, depressed amplitudes at the optic nerve head, and delayed synaptic transduction. Our two patients who had follow up after treatment initiation with folate, Vitamin B complex, and CoQ10 show that clinical improvement correlated with mfERG improvement. Multifocal ERG testing may be useful in diagnosing and monitoring treatment response in patients with nutritional amblyopia.
This is an abstract that was submitted for the 2017 ARVO Annual Meeting, held in Baltimore, MD, May 7-11, 2017.