17 documents found

Article / Chapter
CC BY 4.0
2019-10-22

Pulsed electrical stimulation of the human eye enhances retinal vessel...

Recent studies indicate therapeutic benefits of electrical stimulation in cases of specific ophthalmic diseases that are associated with dysfunctional ocular microcirculation. This suggests effects of electrical stimulation on vascular functions. In the present study, we investigated the effects of electrical...
Lausanne: Frontiers Research Foundation, 2019-10-22
Article / Chapter
CC BY-NC-ND 4.0
2019-07

The effect of different flicker contrasts on the Dynamic Vessel Analysis

Purpose : Retinal arterioles and venules dilate when stimulated with flickering light. This phenomenon is described as functional hyperemia and closely associated with neurovascular coupling. The flicker causes a short period of heightened cellular metabolism which increases the need for blood. As a...
Rockville, Md.: ARVO, 2019-07
Article / Chapter
CC BY-NC-ND 4.0
2019-07

Amplitude changes in the electrophysiological response of retinal cells...

Purpose : Ocular electrical stimulation exhibit potential for the treatment of neurodegenerative ocular diseases. However, the underlying mechanism in the retinal cells remains subject of research. Studies applying transcranial electrical stimulation show that direct current stimulation (DCS) over...
Rockville, Md.: ARVO, 2019-07
Article / Chapter
All rights reserved
2019-03-01

Bleaching effects and fluorescence lifetime imaging ophthalmoscopy

This study investigates the influence of photopigment bleaching on autofluorescence lifetimes in the fundus in 21 young healthy volunteers. Three measurements of 30° retinal fields in two spectral channels (SSC: 498–560 nm, LSC: 560–720 nm) were obtained for each volunteer using fluorescence lifetime...
Washington, DC: OSA, 2019-03-01
Article / Chapter
CC BY-NC-ND 4.0
2018-07

The effect of different rest periods on the Dynamic Vessel Analysis

Purpose : Retinal vessels dilate when stimulated with flickering light. This phenomenon is described as functional hyperemia and closely associated with neurovascular coupling. Flicker light stimulation and investigation of the induced retinal vasodilation, known as dynamic vessel analysis (DVA), is...
Rockville, Md.: ARVO, 2018-07
Article / Chapter
CC BY-NC-ND 4.0
2018-07

Dynamic Vessel Analysis using surface-mount device LEDs as light source

Purpose : In human retinal blood flow research dynamic vessel analysis (DVA) with the Retinal Vessel Analyzer (Imedos Systems UG) is the Gold standard to measure alterations in vessel diameter. However, vessel contrast is often reduced due to stray light caused by illumination of lash, lid, or opaque...
Rockville, Md.: ARVO, 2018-07
Article / Chapter
CC BY-NC-ND 4.0
2018-07

Retinal vessel diameter variations and their correlation to arterial blood...

Purpose : The risk for cardiovascular diseases can be evaluated by the measuring of the retinal blood vessel diameters. Temporal variations in vessel diameter lead to uncertainties. Mayer waves are cyclic variations in cardiovascular system, which can be seen in arterial blood pressure. A link to retinal...
Rockville, Md.: ARVO, 2018-07
Article / Chapter
CC BY-NC-ND 4.0
2018-07

Dark-adapted versus bleached state in fluorescence lifetime imaging ophthalmoscopy

Purpose: The (early) detection of diseases based on metabolic changes in the retina is the goal of the novel autofluorescence lifetime ophthalmoscopy (FLIO) technique. These metabolic changes can be detected as alterations in the fundus autofluorescence (FAF) lifetimes. The influences of the photopigment...
Rockville, Md.: ARVO, 2018-07
Article / Chapter
CC BY-NC-ND 4.0
2017-06

The effect of different adaptation conditions on the dynamic vessel analysis

Purpose : Retinal arterioles and venules dilate when stimulated with flickering light. This phenomenon is described as functional hyperemia. Flicker light stimulation is an established noninvasive means of assessing the endothelial function and the retinal autoregulation by continuous measurement of...
Rockville, Md.: ARVO, 2017-06
Article / Chapter
CC BY-NC-ND 4.0
2017-06

Dynamic retinal vessel analysis using a spatial light modulator for stimulation

Purpose : Dynamic vessel analysis (DVA) with the Retinal Vessel Analyzer (Imedos Systems UG) is the Gold standard to measure alterations in retinal vessel diameter in health and disease. The DVA guidelines provide flicker stimulation of 12.5 Hz in a 30° field of view [1] (fixed full-field). However,...
Rockville, Md.: ARVO, 2017-06
Article / Chapter
CC BY-NC-ND 4.0
2016-09

Scotoma simulation in healthy subjects

Rockville, Md.: ARVO, 2016-09