Hemodynamic Response of the Three Macular Capillary Plexuses in Dark Adaptation and Flicker Stimulation Using Optical Coherence Tomography Angiography
Autor: | Peter L. Nesper, Amani A. Fawzi, Alaa E. Fayed, Hee Eun Lee, Gregory W. Schwartz, Fei Yu |
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Jazyk: | angličtina |
Rok vydání: | 2019 |
Předmět: |
Adult
Male genetic structures Haemodynamic response neurovascular coupling Visual Acuity Hemodynamics Photopsia Dark Adaptation optical coherence tomography angiography Retina Constriction 03 medical and health sciences chemistry.chemical_compound Young Adult 0302 clinical medicine Optical coherence tomography medicine Humans Macula Lutea Fluorescein Angiography Retrospective Studies medicine.diagnostic_test Flicker flicker stimulation Retinal Vessels Retinal General Medicine Blood flow Healthy Volunteers Capillaries chemistry OCT Regional Blood Flow 030221 ophthalmology & optometry Female sense organs medicine.symptom 030217 neurology & neurosurgery Blood Flow Velocity Photic Stimulation Tomography Optical Coherence Biomedical engineering |
Zdroj: | Investigative Ophthalmology & Visual Science |
ISSN: | 1552-5783 0146-0404 |
Popis: | Purpose To assess retinal microvascular reactivity during dark adaptation and the transition to ambient light and after flicker stimulation using optical coherence tomography angiography (OCTA). Methods Fifteen eyes of 15 healthy participants were dark adapted for 45 minutes followed by OCTA imaging in the dark-adapted state. After 5 minutes of normal lighting, subjects underwent OCTA imaging. Participants were then subjected to a flashing light-emitting diode (LED) light and repeat OCTA. Parafoveal vessel density and adjusted flow index (AFI) were calculated for superficial (SCP), middle (MCP), and deep capillary plexuses (DCP), and then compared between conditions after adjusting for age, refractive error, and scan quality. SCP vessel length density (VLD) was also evaluated. Between-condition capillary images were aligned and subtracted to identify differences. We then analyzed images from 10 healthy subjects during the transition from dark adaptation to ambient light. Results SCP vessel density was significantly higher while SCP VLD was significantly lower during ambient light and flicker compared to dark adaptation. There was a significant positive mean value for DCP "flicker minus dark or light," suggesting more visible vessels during flicker due to changes in flow, dilation, or vessel recruitment. We found a significant, transient increase in SCP and decrease in both MCP and DCP vessel density during the transition from dark to light. Conclusions We show evidence suggesting constriction of deeper vessels and dilation of large SCP vessels during the transition from dark to light. This contrasts to redistribution of blood flow to deeper layers during dark adaptation and flicker stimulation. |
Databáze: | OpenAIRE |
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