In silico evaluation of multi-contrast MR fingerprinting for quantification of blood-brain barrier water exchange

Motivation: Blood-brain barrier (BBB) permeability is measurable using T1-contrast MR Fingerprinting (MRF), but incorporating multiple contrasts may improve measurement accuracy and precision, enhancing quantification of BBB water exchange (WEX). Goal(s): Our goal was to evaluate the potential of leveraging longitudinal and transverse relaxation to measure cerebral blood volume and intravascular residence time using MRF. Approach: We extended and optimised a BBB WEX simulation to include T2 effects, simulating a fast imaging with steady-state precession (FISP) MRF sequence, and performed dictionary matching on simulated signals with and without noise Results: Including multiple contrasts improves sequence sensitivity to intravascular residence time, with good parameter matching capability. Impact: Preliminary simulations indicate that using multi-contrast MRF for water-exchange measurements improves sensitivity to intravascular residence time, yielding the potential for enhanced quantification of BBB permeability. Further optimisation and noise reduction will further improve matching accuracy.