Screening for diabetic retinopathy using new mydriasis-free, full-field flicker ERG recording device

Abstract

Diabetic retinopathy (DR) is a leading cause of blindness among working-age adults. Therefore, it is important to detect DR accurately during mass screening. The purpose of this study was to determine whether a small, hand-held, mydriasis-free, full-field flicker electroretinographic (ERGs) device called RETeval can be used to screen for DR. To accomplish this, we recorded full-field flicker ERGs with this device from 48 normal eyes and 118 eyes with different severities of DR in patients with diabetes mellitus (DM). This system delivered a constant flash retinal luminance by adjusting the flash luminance that compensated for changes in the pupil size. Our results showed that there were significant correlations between the severity of DR and the implicit times (P < 0.001; r = 0.55) and the amplitudes (P = 0.001; r = −0.29). When the implicit time was used for the index, the area under the receiver operating characteristic curve was 0.84 for the detection of DR, and was 0.89 for the detection of DR requiring ophthalmic treatments. These results suggest that the implicit times of the flicker ERGs recorded by the small, mydryasis-free ERG system can be used as an adjunctive tool to screen for DR.

Factors Affecting Mydriasis-Free Flicker ERGs Recorded With Real-Time Correction for Retinal Illuminance: Study of 150 Young Healthy Subjects

“…Therefore, we believe that the differences of 1.5 ms associated with pupil size or axial length are substantial when considering the classification of patients for flicker ERGs. 23 There are three limitations in this study. The first limitation is that we measured mainly the fundamental component of flicker ERGs while the measurements of the peak implicit times or peak-to-peak amplitudes are more generally used in clinical situations.…”

“…The components of the RETeval system have been described in detail. [16][17][18][19][20][21][22][23] In brief, full-field stimuli are presented with a 60-mm diameter dome, and the white stimuli are created by a combination of three colored light emitting diodes. The frequency of the flicker stimulus was 28.306 Hz, and the pulse duration was less than 1 msec.…”

“…This system can record flicker ERGs without mydriasis because the device delivers stimulus flashes with constant retinal illuminance (Td-s) by adjusting the luminance (cd-s/m 2 ) to compensate for changes in the pupillary area (mm 2 ) in real time. Two recent studies 22,23 reported that the implicit time of fundamental component of flicker ERG recorded by RETeval was a useful index of retinal function with high sensitivity of detecting diabetic retinopathy (DR) or DR requiring ophthalmic treatment. However, it has not been determined what factors can affect the implicit times or amplitudes of the fundamental component of the flicker ERGs obtained by RETeval in healthy subjects.…”

Temporal Frequency Abnormalities in Early-Stage Diabetic Retinopathy Assessed by Electroretinography

“…In later stages of the disease, the photopic single-flash b-wave and flicker ERG can become reduced in amplitude and/or delayed. 20 – 23 Given these findings, as well as the recent availability of a portable instrument for recording the flicker ERG, there has been renewed interest in the flicker ERG as a tool to screen for sight-threatening DR. 24 – 26 Previous studies of the flicker ERG in diabetes have almost exclusively elicited the response by using full-field periodic flashes of light at a flicker rate of approximately 30 Hz, the frequency recommended by international standards. 27 However, a recent report from our group has shown value in recording the ERG elicited by higher flicker rates.…”

Supernormal Flicker ERGs in Eyes With Central Retinal Vein Occlusion: Clinical Characteristics, Prognosis, and Effects of Anti-VEGF Agent

“…There are several reports of the presence of supernormal ERG amplitudes in eyes with retinal vascular disorders including eyes with diabetic retinopathy 17,18 and CRVO. [19][20][21][22] In 1992, Gouras and Mackay 21 reported that 4 of 12 eyes with a CRVO had supernormal single-flash cone ERGs when conventional white flash stimuli were used.…”