Fig. 2.

Plots showing the correlation of all signal changes for PET (x-axis) and fMRI (y-axis). A) shows the correlation of absolute values of signal change showing a weak, but significant correlation (r = 0.35, p = 0.001). B–D) shows values calculated as the quotient of absolute values in the respective vascular territories and signal of the cerebellum with strong correlation. B) depicts territories of all patients (r = 0.71, p < 0.001), C) of all patients with preoperative (r = 0.61, p < 0.001) and D) of all patients with postoperative imaging (r = 0.76, p < 0.001).