Screening electro-oculography protocol as a part of full-field electroretinography

To simplify the electro-oculography (EOG) method and integrate it into the full-field electroretinogram (ffERG) protocol for screening purposes.

20 control subjects and 5 patients with Best vitelliform macular dystrophy (BVMD) underwent EOG recording according to both the standard protocol and screening EOG protocol that was integrated as part of ffERG testing. Mean values of light peak-to-dark trough ratio (LP:DT ratio) were compared between both protocols using the Student's t-test, sensitivity and specificity for the detection of RPE dysfunction were evaluated with ROC analysis and a survey on the difficulty of each protocol was completed by each subject.

With the standard EOG mean LP:DT ratio was 2.67 ± 0.61 in controls and 1.12 ± 0.16 in BVMD patients (p < 0.001). With the screening protocol mean LP:DT ratio was 1.98 ± 0.33 in controls and 1.02 ± 0.14 in BVMD (p < 0.001). A comparison of LP:DT ratios showed significant difference between the standard and the screening protocol (p < 0.01 in controls; p = 0.02 in BVMD), however both protocols showed 100% sensitivity and 100% specificity for detection of BVMD. Patients stated that participation in the screening protocol was easier and less uncomfortable.

Screening EOG performed as part of ffERG gives comparable results to standard EOG, examination is patient-friendly, time saving and can be used as a preliminary test for the assessment of RPE function.