Reproducibility of retinal oximetry measurements in healthy and diseased retinas

Acta Ophthalmol. 2015 Sep;93(6):e439-45. doi: 10.1111/aos.12598. Epub 2014 Nov 27.

Abstract

Purpose: Retinal oximetry (RO) has been established as a non-invasive method to analyse oxygen saturation in retinal vessels. The aim of our study was to determine the reproducibility of RO images in healthy and in diseased retinas.

Methods: A total of 61 right eyes (244 RO images) in 61 subjects (35♀, 26♂) were examined: 22 controls, 18 patients with glaucoma and 21 patients with inherited retinal diseases (IRDs). Four test-retest RO images were obtained in each subject. Oxygen saturation was measured with the oxygen saturation measurement tool of the Retinal Vessel Analyser (RVA; IMEDOS Systems UG, Jena, Germany). The test-retest standard deviation within the subject's (±SDw ) measurements (the mean vessel oxygen saturation in retinal venules and arterioles), its coefficient of variation (CoV) and the intraclass correlation coefficients (ICC) were analysed.

Results: The average test-retest SDw in venules was ±2.52% (CoV = 4.35%) and in arterioles was ±1.67% (CoV = 1.76%). Among controls, glaucoma eyes and eyes with IRDs, the test-retest SDw in venules were ±2.33% (CoV = 4.48%), ±2.85% (CoV = 4.71%) and ±2.43% (CoV = 3.90%) (SDw p = 0.366 (CoV p = 0.452); one-way anova). The test-retest SDw in arterioles were ±1.65% (CoV = 1.80%), ±1.83% (CoV = 1.92%) and ±1.54% (CoV = 1.56%), respectively [SDw p = 0.762 (CoV p = 0.686)]. The ICCs in venules were 0.76 in controls, 0.69 in patients with glaucoma and 0.82 in patients with IRD. The ICCs in arterioles were, respectively, 0.92, 0.70 and 0.93.

Conclusion: The reproducibility of RO in healthy, as well as in diseased retinas, is excellent. In the glaucoma group, the lower standard deviation between subjects (SDb ) for arterioles contributes to the lower ICCs. Nevertheless, the measurements of oxygen saturation in arterioles seem more reliable when compared to venules.

Keywords: controls; glaucoma; inherited diseases of the retina; oxygen saturation; reproducibility; retinal vessel oximetry.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Arterioles / physiology
  • Female
  • Glaucoma / physiopathology*
  • Humans
  • Male
  • Middle Aged
  • Oximetry / standards*
  • Oxygen / blood*
  • Oxygen Consumption
  • Reproducibility of Results
  • Retinal Degeneration / physiopathology*
  • Retinal Vessels / physiology*
  • Venules / physiology
  • Young Adult

Substances

  • Oxygen