Effects of image brightness and contrast dynamic altering stimuli (DAS) when viewing video content on ocular blood flow.

Background/aim: Blood flow deficiencies of the retinal and retrobulbar circulations have been previously reported in open-angle glaucoma (OAG) and other eye diseases. Herein we investigated the effects of image brightness and contrast dynamic altering stimuli (DAS) when viewing a video content on ocular blood flow, intraocular pressure (IOP) and ocular perfusion pressure (OPP) in OAG and healthy subjects.
Methods: Thirty-five subjects, 25 with OAG (mild to moderate) and 10 healthy controls, were evaluated for blood pressure, IOP, OPP and retinal capillary blood flow before, immediately after, 30 min after and 60 min after using ReviView (a dichoptic video goggles device), which stimulates one eye with a DAS video image that is brighter and with greater contrast than the fellow eye (duration of exposure 30 min). Differences between each subject's eyes and between OAG and healthy subjects were evaluated using repeated-measures analysis of variance with p<0.05 considered statistically significant.
Results: All subjects demonstrated a significant increase in OPP in both eyes immediately following viewing. In all DAS eyes, retinal capillary blood flow rose immediately after stimulation and remained elevated for an hour postviewing. Viewing DAS increased retinal blood flow compared with control eyes (p=0.0014, 0.0135 superiorly and p=0.0094, 0.0001 inferiorly, at 30 and 60 min, respectively). OAG eyes had a significant reduction in the number of dormant retinal capillaries (p=0.0174), while healthy eyes demonstrated a larger increase in retinal capillary blood flow (p=0.0006 and p=0.0093 at 60 min, superior and inferior, respectively) following DAS viewing.
Conclusion: Viewing DAS video for 30 min using ReviView increased retina blood flow both in healthy subjects and in patients with OAG.
Trial Registration Number: NCT02959593.
Competing Interests: Competing interests: AH would like to disclose that he receives remuneration from CIPLA, AdOM and Shire for serving as a consultant. AH also holds an ownership interest in AdOM and Oxymap. All relationships listed above are pursuant to Indiana University’s policy on outside activities.​ The contribution of ACVV was supported by Fondazione Roma and by the Italian Ministry of Health.
(© Author(s) (or their employer(s)) 2019. No commercial re-use. See rights and permissions. Published by BMJ.)