Comparison of single-band versus multi-band phase contrast MRI for the estimation of pulse transit time as a measure of neurovascular stiffness

Motivation: Neurovascular pulse wave velocity (PWV) measurements have the potential to quantify vascular risk locally in the brain but are limited by the long acquisition time of sequential single-band scans. Goal(s): We aim to compare the reproducibility of neurovascular pulse transit time (PTT) measurements in single-band and multi-band phase contrast MRI (PC-MRI) acquisitions. Approach: Four subjects were scanned at 3T with repeated single-band and multi-band PC-MRI scans. The differences in repeated PTT measurements are compared across acquisition types for multiple vascular paths. Results: The full time-efficiency improvement of multi-band acquisition was achieved with no significant difference in PTT reproducibility. Impact: Phase contrast MRI scans for the assessment of neurovascular stiffness can be accelerated by a factor of five through a simultaneous multi-slice acquisition without a significant difference in the reproducibility of pulse transit time measurements.