Purchase this article with an account.
Iman Goharian, Shawn M Iverson, Rosa Catalina Ruiz, Krishna S Kishor, David S Greenfield, Mitra Sehi; Retinal Oxygen Saturation in Treated Glaucomatous Eyes. Invest. Ophthalmol. Vis. Sci. 2014;55(13):4732. doi: https://doi.org/.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
To prospectively examine retinal oxygen saturation levels and measurement reproducibility in treated glaucomatous eyes compared with normal controls.
Glaucoma patients and normal controls were included. Exclusion criteria for both groups were visual acuity <20/30, unreliable visual fields, thyroidopathies, hemoglobinopathies, cardiovascular and pulmonary diseases. Retinal oximetry was performed twice consecutively on one randomly selected eye of glaucoma patients and normal controls using spectrophotometric retinal oximeter (Oxymap ehf., Iceland). Superior and inferior temporal and nasal arteries and veins were separately analyzed. The average oxygen saturation in arteries (a.SO2) and veins (v.SO2) and the arteriovenous difference (ΔSO2) representing oxygen usage were calculated. Coefficients of variability (CoV), and intraclass correlation coefficients (ICC) were calculated. Analysis of variance and regression analyses were performed.
23 glaucoma patients (mean age 68.3±10.8 yrs) and 22 normal controls (mean age 61.5±18.2 yrs; p=0.14) were included. The intraocular pressure (IOP) and mean ocular perfusion pressure (MOPP) in glaucoma (14.4±4.2mmHg; 45.8±5.8mmHg) and controls were similar (14.3±3.3mmHg; 45.8±6.1mmHg; p>0.05). In the glaucoma group, the a.SO2 had a CoV of 1.6% and an ICC of 0.97; and the v.SO2 had a CoV of 5.9% and an ICC of 0.96. In normals, the a.SO2 had a CoV of 0.98% and an ICC of 0.97; and v.SO2 had a CoV of 4.8% and an ICC of 0.93. In glaucomatous eyes, the ΔSO2 was higher than controls (47.6±8.2%; 42.1±6.2%; p=0.015).There was no significant difference between glaucomatous eyes and controls for a.SO2 (92.9±6.7%; 90.1±4.9% respectively; p=0.11) or v.SO2 (45.4±11.0%; 48.0±7.7% respectively; p=0.36). There was an inverse correlation between a.SO2 and age (r= 0.53; p=0.009) in glaucoma. The a.SO2 and visual field pattern standard deviation were correlated (r=0.46; p=0.03) in glaucoma. Diabetes and systemic hypertension had no association with a.SO2, v.SO2 or ΔSO2 (p>0.05) in either group.
Retinal oximetry measurements are highly reproducible in both glaucomatous and normal eyes. Retinal oxygen usage is higher in treated glaucomatous eyes compared with age-matched normal controls.
This PDF is available to Subscribers Only