Effects of Noise on Blood-Brain Barrier Permeability Measurement Error in Diffusion Weighted and Multi-Echo Arterial Spin Labeling MRI

Arterial spin labeling (ASL) MRI is noninvasive and has the potential to become a sensitive, clinically useful way to measure blood-brain barrier (BBB) permeability. Here, we focused on two different ASL sequences, diffusion-weighted (DW) and multi-echo (T2), and performed simulations to compare the robustness of BBB permeability (Texch) measurement to different levels of noise. We conclude that the Texch fitting for DW ASL is more robust to noise at a physiological arterial transit time (ATT) of 1000ms at the expense of being more vulnerable to bias when the assumed ATT deviates from the true underlying ATT.