Ontology highlight
ABSTRACT: Purpose
To detect how systemic hyperoxia affects oxygen saturation in retinal arterioles and venules in healthy individuals.Methods
Retinal vessel oxygen saturation was measured in 30 healthy individuals with a spectrophotometric retinal oximeter (Oxymap T1). Oximetry was performed during breathing of room air, 100% oxygen (10 minutes, 6L/min) and then again room air (10 minutes recovery).Results
Mean oxygen saturation rises modestly in retinal arterioles during 100% oxygen breathing (94.5%±3.8 vs. 92.0%±3.7% at baseline, p<0.0001) and dramatically in retinal venules (76.2%±8.0% vs. 51.3%±5.6%, p<0.0001). The arteriovenous difference decreased during 100% oxygen breathing (18.3%±9.0% vs. 40.7%±5.7%, p<0.0001). The mean diameter of arterioles decreased during 100% oxygen breathing compared to baseline (9.7±1.4 pixels vs. 10.3±1.3 pixels, p<0.0001) and the same applies to the mean venular diameter (11.4±1.2 pixels vs. 13.3±1.5 pixels, p<0.0001).Conclusions
Breathing 100% oxygen increases oxygen saturation in retinal arterioles and more so in venules and constricts them compared to baseline levels. The dramatic increase in oxygen saturation in venules reflects oxygen flow from the choroid and the unusual vascular anatomy and oxygen physiology of the eye.
SUBMITTER: Olafsdottir OB
PROVIDER: S-EPMC4456093 | biostudies-literature | 2015
REPOSITORIES: biostudies-literature
Olafsdottir Olof Birna OB Eliasdottir Thorunn Scheving TS Kristjansdottir Jona Valgerdur JV Hardarson Sveinn Hakon SH Stefánsson Einar E
PloS one 20150604 6
<h4>Purpose</h4>To detect how systemic hyperoxia affects oxygen saturation in retinal arterioles and venules in healthy individuals.<h4>Methods</h4>Retinal vessel oxygen saturation was measured in 30 healthy individuals with a spectrophotometric retinal oximeter (Oxymap T1). Oximetry was performed during breathing of room air, 100% oxygen (10 minutes, 6L/min) and then again room air (10 minutes recovery).<h4>Results</h4>Mean oxygen saturation rises modestly in retinal arterioles during 100% oxyg ...[more]