Fig. 2.

Percent change in laser Doppler flow as a function of the measured sagittal sinus O₂ saturation in the hypoxia-only group (HYP), hypoxia plus unilateral carotid artery occlusion group (UCAO), and hypoxia plus bilateral carotid artery occlusion group (BCAO). *P < 0.05, ***P ≤ 0.001, and ****P ≤ 0.0001 from 30 to 100% oxygen saturation by unpaired t-test. HYP group was statistically significantly different from the UCAO and BCAO groups in the range of 15–30% measured O₂ saturation (P = 0.0036 and 0.0237, respectively) and also in the range of 0–15% O₂ saturation (P = 0.0001).