For instance, in patients with AD, structural MRI data has shown an increase in CP volume with disease severity [12–14], arterial spin labelling (ASL) MRI and dynamic contrast enhanced (DCE) MRI have shown alterations in CP blood flow [14] and permeability to contrast agent, respectively [12], while dynamic PET has revealed a reduction in CSF clearance of tau and amyloid tracers [15–17]. Here, CP is linked to Alzheimer disease.