ABSTRACT

Objective:

Full-field electroretinography (ERG)is the only available technology to provide objective, quantifiable and global assessment of retinal function. Laboratory-based Flicker ERG has previously been described as a reliable tool in quantifying retinal dysfunction in diabetic retinopathy (DR). We evaluated the inter-session reproducibility of the office-based Diopsys NOVA Flicker ERG in patients with mild-to-moderate NPDR. We also examined correlations among clinical, imaging and flicker parameters.

Methods:

This was a single practice, observational case series. We included patients with mild-to-moderate NPDR and BCVA of 20/50 or better. Ultra-widefield angiography (UWFA) was performed on all eyes with images being sent to a Reading Center for grading by a masked reader. An ischemic index was determined for each eye. Fixed and multi-luminance flicker ERG was repeated on both eyes on 4 separate days, at least 7 days apart, using 2 Diopsys machines located in 2 offices in different states. Consistency of recordings was assessed using coefficients of variation (CV) and intra-class correlation coefficients (ICC). Pearson correlation coefficients were also calculated.

Results:

20 consecutive patients were evaluated. The Reading Center graded 82.5% and 17.5% of eyes with mild and moderate NPDR, respectively; 90% had high confidence scores. Fixed- and multi-luminance magnitude values and fixed-luminance phase values were highly reproducible; fixed-luminance phase values were the most reproducible (ICC=0.949; p<0.001). There were significant negative correlations between fixed-luminance phase and log-corrected ischemic index values (-0.426; p=0.015) and between fixed-luminance magnitude and HbA1c values (-0.436; p=0.010).

Conclusions:

Office-based, fixed-luminance flicker ERG phase values are highly reproducible and negatively correlate with the degree of retinal ischemia in DR. This technology holds the potential to initially quantify global retinal dysfunction in diabetes and possibly monitor eyes with mild-to-moderate NPDR.


CONTACT DETAILS

John J. Wroblewski
Cumberland Valley Retina Consultants
Hagerstown, Maryland
United States
Email : johnw@retinacare.net
Cell Phone: +13014810765
Work Phone: +13016651712