Electroretinographic findings in retinal vasculitis

Abstract

Purpose : In this case series, we aim to describe electroretinographic responses and assess their correlation with clinical and angiographic findings in retinal vasculitis.

Methods : Medical records of patients who were diagnosed with retinal vasculitis at a tertiary eye center from December 2017 to May 2021 were reviewed. Cases in which both fluorescein angiography (FA) and electroretinography (ERG) were done within one month were included. Cases with other retinal diagnoses or significant media opacities were excluded. FAs were graded according to the Angiography Scoring for Uveitis Working Group scoring system from 0 to 40, where 0 is normal. Individual ERG waves were graded for both timing and amplitude, based on their corresponding Z (standard deviation) scores from 0 to 5, where 5 is normal and 0 is absent response. General ERG score was determined by mean of individual scores plus 1 point if the oscillatory potential was present. Relevant clinical data were obtained. General and individual ERG scores were correlated with FA scores and clinical findings.

Results : 34 eyes of 20 patients were included. Mean age was 43.9 ± 19.8 years; 70% were female. Underlying ocular diagnoses were isolated vasculitis (70%), intermediate uveitis (20%) and panuveitis (10%). Median (range) best corrected visual acuity (BCVA) was 0.8 (0.08-1). Optical coherence tomography was normal in 59% of eyes. Mean FA severity score was 12.6 ± 6.5. Median general ERG score was 5 (0 to 6). 68% and 91% of eyes had responses with general scores ≥ 5 & 4, respectively. Among ERG parameters, flicker timing was the most commonly and severely affected.
FA scores weakly correlated with delayed photopic cone b wave and flicker timing (P = 0.03 and 0.016, respectively). FA scores did not correlate with general ERG or any other individual wave scores. Vitreous haze gradings moderately correlated with delayed cone b wave timing (P < 0.001), delayed flicker timing (P = 0.002) and weakly correlated with lower flicker amplitude (P = 0.03). Lower BCVA weakly correlated with delayed cone b wave timing (P=0.046).

Conclusions : Retinal vasculitis is not frequently associated with severe retinal dysfunction. Lower BCVA, higher FA scores, and vitreous haze gradings are weakly correlated with cone related ERG abnormalities. ERG may provide functional assessments not otherwise predicted by clinical or angiographic finding in retinal vasculitis.

This abstract was presented at the 2022 ARVO Annual Meeting, held in Denver, CO, May 1-4, 2022, and virtually.