Figure 6. Directional diffusivity in the evaluation of a family with leukodystrophy.
From left, fluid-attenuation inversion recovery, rotational atherectomy map with ellipsoid and color tensor encoding, and the corresponding radial diffusivity parameter maps. This subject is a gene carrier in a family with Pelizaeus–Merzbacher’s disease. Unlike chronic microangiopathy of the elderly, which presents with small periventricular T2 hyperintense lesions on fluid-attenuation inversion recovery and T2-weighted images, which are characterized by elevations in both axial and radial diffusivity, this subject has more peripheral lesions (circled on the fluid-attenuation inversion recovery image and corresponding radial diffusivity map), which have elevated radial diffusivity and preserved axial diffusivity. These findings are expected in a carrier of a leukodystropy gene defect.
Reproduced with permission from [3].