Retinal oximetry using ultrahigh-resolution optical coherence tomography

Abstract

Background

The purpose of this study was to investigate the repeatability of retinal oximetry using slit-lamp adapted ultrahigh-resolution optical coherence tomography (SL-UHR-OCT).

Methods

SL-UHR-OCT was developed and fringe patterns were obtained for a major retinal artery and a major retinal vein. A-scans at the central wavelengths of 805 nm and 855 nm were analyzed for calculating optical density ratios (ODRs), from which the percentage oxygen saturation was calculated. Measurements were made on two occasions for each person. Repeatability and coefficients of repeatability were calculated.

Results

The mean ODRs of the artery were 0.79 ± 0.86 and 0.88 ± 0.97 in sessions 1 and 2, respectively. The mean ODRs of the vein were −0.08 ± 0.69 and 0.14 ± 0.77 between the two sessions, and were significantly lower than that of the artery (P < 0.05). The coefficients of repeatability were 1.44 and 1.81 for the artery and vein, respectively. The mean oxygen saturation of the major retinal artery was 94% ± 45% and 98% ± 51% in sessions 1 and 2, respectively, and the mean oxygen saturation of the major retinal vein was 48% ± 36% and 60% ± 40% between sessions.

Conclusion

Optical coherence tomographic oximetry for evaluating retinal oxygen saturation was subject to variation, although the averaged measurements in repeated sessions were matched. Further work on reducing variation will be needed.

Keywords:

• ultrahigh-resolution optical coherence tomography
• oximetry

Acknowledgments

This study was in part supported by research grants from the National Institutes of Health (P30EY014801, R01EY020607, R01EY020607S) and from Research to Prevent Blindness.

Disclosure

The authors report no conflicts of interest in this work.