Retinal Oxygen Saturation during Hyperoxia in Healthy Individuals

Abstract

Purpose: : To detect whether hyperoxia affects oxygen saturation in retinal arterioles and venules in healthy individuals. To test the sensitivity of a retinal oximeter.

Methods: : Retinal vessel oxygen saturation was measured in 31 healthy individuals with a spectrophotometric retinal oximeter (Oxymap ehf., Reykjavik, Iceland). Oximetry was performed during breathing of room air, during breathing of 100% O₂ (10 minutes, 6L/min) and then again during breathing of room air (10 minutes recovery). Statistical analysis was performed with Student’s t-test for paired measurements.

Conclusions: : The retinal oximeter measures stable baselines and is sensitive to changes in O₂ saturation and vessel diameter. Breathing 100% O₂ increases oxygen saturation in retinal arterioles and venules and constricts them compared to normoxic levels.

Keywords: oxygen • retina • imaging/image analysis: clinical