Characterization of human brain IVIM signal using two-dimensional T2-diffusivity spectrum analysis based on multi-echo diffusion MRI

Motivation: It is still controversial whether the parameters derived from conventional IVIM data measured in brain tissue truly arise from vascular compartments. Concerns have been raised about biases introduced by contamination from CSF due to partial volume effects. Goal(s): Removing CSF contamination and characterizing human brain IVIM signals. Approach: A two-dimensional T2-diffusivity spectrum analysis based on multi-echo diffusion MRI was used to separate distinct compartments. Results: The results indicate the existence of a blood and both a fast and slow CSF component. CSF contamination can be effectively removed with this approach. Impact: We demonstrated that CSF contamination in human brain IVIM signals can be effectively removed with a two-dimensional T2-diffusivity spectrum analysis based on multi-echo diffusion MRI. Whether the extracted blood compartment can reveal microvascular flow information will require further studies.