Abstract
Purpose :
Static automated perimetry is ubiquitously utilized in visual function assessment for glaucoma diagnosis, but can be limited by subjectivity in patient responses, requirement of expensive, bulky equipment and a trained technician, and patient dislike for the testing paradigm. This study evaluated the diagnostic performance of a sinusoidal flicker stimulus test at various frequencies using a portable handheld electroretinography (ERG) device in glaucoma vs control participants. We hypothesized that higher frequency stimuli would have greater discriminatory ability because the OFF pathway, which may predominate at higher frequencies, is more susceptible in glaucoma.
Methods :
In this cross-sectional study, participants with a glaucoma diagnosis and controls were recruited from ophthalmology and optometry clinics. The RETeval device (LKC Technologies), a handheld ERG recording system, was used to administer a sinusoidal flicker stimulus modulated at 14 frequencies from 1 to 50 Hz, and the first harmonic frequency response amplitudes were collected. Logistic regression models with glaucoma diagnosis as the outcome and amplitude responses at various frequencies as the explanatory variables were trained using data from 67% of participants; models were then tested on the remaining 33% of participants. Receiver operating characteristic curves demonstrating model performance on the testing set were generated and area under the curve (AUC) was calculated.
Results :
117 eyes from 72 participants (18 control, 54 glaucoma, mean age [SD]=70.4[12.2] years, 51.4% female) were included. Among glaucomatous eyes, average(SD) mean deviation was -4.61(5.55) dB. In a model using the combined effects of the amplitude responses measured at all frequencies, the AUC was 0.57 (95% CI:0.37-0.78). In a model using measurements from frequencies only 30Hz and greater, where the OFF pathway may predominate, the AUC was 0.81 (95% CI:0.66-0.97). In this higher frequency model, sensitivity was 80% and specificity was 74% at the Youden’s J cutoff.
Conclusions :
These results demonstrate evidence supporting handheld electroretinography to diagnose glaucoma by measuring retinal amplitude responses to sinusoidal flicker stimuli at frequencies between 30 and 50Hz, supporting the hypothesis that the OFF pathway may be more susceptible in glaucoma.
This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.