Relationship between Retinal Oxygen Saturation and the Severity of Visual Field Damage in Glaucoma

Précis: Increased oxygen saturation (StO 2 ) was significantly associated with the severity of visual field (VF) damage in patients with glaucoma. Objective: To investigate the association between retinal StO 2 percentage and the severity of VF loss in glaucoma. Methods: A total of 198 eyes from 131 patients with glaucoma were included in this cross-sectional study. Participants underwent imaging using ocular oximetry (Zilia) and 24-2 Swedish Interactive Threshold Algorithm standard VF (Carl Zeiss-Meditec). StO 2 (%) was measured at 2 locations of the peripapillary optic nerve head (superotemporal, and inferotemporal). Measurements were reported as the mean of at least 5 measurements in each location. Associations between the severity of VF loss, reported as mean deviation, and StO 2 (%) were calculated. Results: A total of 198 eyes of 131 patients (mean (95% CI) age, 71.1 (68.9,73.3) years, 68 females (51.9%), and 63 males (48.1%) were analyzed. In univariable analysis, higher StO 2 −0.06 (−0.12, 0.00) was associated with severity in all hemifields ( P = 0.047). Multivariate regression analysis showed that each 1% increase in StO 2 was associated with −0.06 (−0.12, -0.00) dB loss in mean deviation in all hemifields ( P = 0.043). In multivariate regression analysis in the superior hemifields, higher StO 2 −0.07 (−0.16, 0.01) tended to be associated with superior hemifield severity ( P = 0.09). Conclusions: Retinal oximetry enabled the continuous quantitative measurement of retinal StO 2. Increased StO 2 was significantly associated with the severity of VF damage in patients with glaucoma.