Associations among Cognitive Functions, Plasma DNA, and Diffusion Tensor Image along the Perivascular Space (DTI-ALPS) in Patients with Parkinson’s Disease

Figure 2

(a) DTI color map shows the direction of the projection fibers (blue; -axis), association fibers (green; -axis), and the subcortical fibers (red; -axis). Three ROIs are placed to measure diffusivities of the three fibers. (b) Schematic diagram presents the relationship between the direction of the perivascular space (gray cylinders), the fibers, and the formula of the ALPS-index. Note that the direction of the perivascular space is perpendicular to both projection and association fibers.

(a)

(b)