Motivation: Blood-oxygenation-level-dependent cerebrovascular reactivity (BOLD-CVR) is increasingly used to assay impairment in moyamoya disease, however BOLD-CVR response to surgery has not been fully characterized with a fixed inspiration stimulus. Goal(s): To fully characterize the temporal BOLD-CVR response to revascularization surgery in MMD patients and test the relative sensitivities of a time-shift regression analysis against an exponential model of BOLD-CVR to revascularization surgical changes. Approach: Time-shift regression and exponential model analysis were applied in 33 brain hemispheres of moyamoya participants before and after revascularization surgery. Results: With a fixed-hypercapnic stimulus, the temporal BOLD-CVR response was highly sensitive to changes due to revascularization surgery. Impact: Cerebrovascular reactivity (CVR) response times in both time-shifted and exponential models were significantly decreased in response to revascularization surgery in moyamoya patients, motivating the utilization of CVR response times as a biomarker to evaluate treatment in moyamoya disease.
Richerson et al. (Tue,) studied this question.