Abnormal cerebral vascular morphology Cerebral perivascular enhancement pattern Focal, regional or diffuse magnetic resonance imaging (MRI) enhancement of intracranial perivascular spaces (PVS). This enhancement pattern is recognizable by its topography that follows PVS distribution, particularly identifiable in regions where PVS predominate (centra semiovalia, basal ganglia and the brachium pontis)15 although it can be found throughout the whole brain. Depending on the perpendicular or parallel orientation of MRI sections to the long axis of PVS, enhanced PVS appear as dots or curvilinear elements respectively. Depending on the causal pathology, PVE may appear more linear or nodular. Perivascular enhancement pattern Perivascular spaces (PVS) are fluid-filled structures that form the immediate peripheral environment of small cerebral vessels. They are a central component of the glymphatic system, which plays a crucial role in maintaining cerebral homeostasis.