Voxel-wise DCE-MRI model selection impacts estimates of blood-brain barrier leakage in stroke

Motivation: Different models of DCE-MRI tracer leakage may fit better in different brain regions in cerebrovascular disease and could provide additional insight into BBB function. Goal(s): Demonstrate the utility of voxel-wise DCE-MRI model selection in stroke. Approach: Fit the Extended Tofts, Patlak, and Intravascular models of DCE-MRI tracer leakage to data from controls, ischaemic stroke, and intracerebral haemorrhage patients on a voxel-wise basis, and select the best-fitting model for each voxel using the Akaike Information Criterion. Results: Different models are preferred in different tissue types and disease groups. Model selection increases inter-patient variance of Ktrans compared to Patlak alone. Impact: The Patlak model may not be the most appropriate model for DCE-MRI measurements of blood-brain barrier leakage in ischaemic stroke. Best-fitting model maps could help delineate the extent of “leaky” vs “non leaky” regions based on nested model assumptions.