Non-invasive blood brain barrier integrity mapping in patients with high-grade glioma and metastasis by time-encoded arterial spin labelling

High-grade glioma are known to cause blood brain barrier (BBB) disruption, facilitating molecular leakage from inside the vessels into tissue. Current methods to probe BBB integrity are either not quantitative or, by using Gadolinium, insensitive to subtle changes. Here, we present first data of arterial spin labelling (ASL)-based BBB mapping of water exchange time (Texch) in brain tumour patients. Results show faster exchange (shorter Texch) in tumorous and even normal-appearing tissue compared to healthy subjects. This highlights the potential of ASL-based water exchange mapping as a proxy measure for BBB integrity, and its potential sensitivity to even subtle impairments.