Comparing short-duration electro-oculogram with and without mydriasis in controls

Purpose In order to obtain artefact-free EOG recordings the subject’s cooperation is necessary. The aim of our study is to evaluate recording characteristics of the short-duration EOG and to compare the effect of mydriasis on EOG recordings in a cohort of controls. Methods EOG recordings were performed on a LED stimulus screen using a RETI-port gamma plus2 system (RETIscanTM, Roland Consult). Dark phase included: pre-adaptation (6min), alternate fixation (4min), fixation-rest (20sek), 100 sweeps. Light phase included: light adaptation (4min), alternate fixation (10min), fixation-rest (20sek), 250 sweeps. Amplifier was band pass filtered at 0.1-50Hz. Background illumination in mydriasis was 100cd/m2 and in miosis 450cd/m2. Fast oscillations were set at 1.5sek (6 cycles; total duration 75sek). Results A total of 55 controls divided in three age-groups participated (number; mean (years, y); ±SD): group 1: 18- 20y (19; 19.49y; ±0.89); group 2: 20-40y (18; 27.91y; ±5.39) and group 3: 40-60y (18; 48.66y; ±4.00). Arden ratio (AR), dark-trough (DT) and light-peak (LP) did not differ between recordings with or without mydriasis (p=0.885; p=0.860; p=0.776, linear mixed-effects model). Age did not influence the AR, DT, LP (p= 0.206; p=0.112; p=0.155). AR, DT, LP were comparable between eyes tested (p=0.998; p=0.196; p=0.324). Conclusion Short-duration EOG allows successful recording, where the application of mydriasis does not influence the quality of the recording.