Retinal Oxygen Saturation is Affected in Central Retinal Vein Occlusion

Abstract

 

Purpose

 

To evaluate the effect of central retinal vein occlusion (CRVO) on retinal vessel oxygen saturation.

 

Methods

 

The Oxymap T1 retinal oximeter (Oxymap ehf., Reykjavik, Iceland) is based on a fundus camera and analysis software. It simultaneously captures images of the retinal vessels at 570 nm and 600 nm for calculation of hemoglobin oxygen saturation. The mean oxygen saturation in retinal arterioles and venules of both eyes was measured in 11 patients with unilateral CRVO before treatment. One patient was followed over a period of five months.

 

Results

 

In the 11 CRVO eyes, the mean venular oxygen saturation was 24 ± 22% (mean±standard deviation) compared with 57 ± 8% in fellow eyes (p= 0.004, paired t-test). In the CRVO eye with the greatest variability, the venous saturation ranged from 8% to 63%. In CRVO eyes, the mean retinal arteriolar oxygen saturation was 96 ± 6 % vs. 94 ± 6 % in fellow eyes (p=0.3).

 

Conclusions

 

CRVO eyes had lower mean oxygen saturation in retinal venules than fellow eyes. The variation of venular oxygen saturation was substantial within each eye. The difference in arteriolar saturation was not significant. The reduction in venular saturation indicates compromised retinal blood flow following a central retinal vein occlusion.

 

 

The figure shows oxygen saturation in the CRVO eye and the fellow eye in the same patient.

 

 

The figure shows the mean oxygen saturation in retinal vessels.

 

Keywords: 635 oxygen • 688 retina • 550 imaging/image analysis: clinical