FIG 3. Case 4.

A and B, Coronal T2-weighted images (3648/99/2) of adjacent sections, A posterior to B, show nearly symmetrical involvement of the corticospinal tract from the cortex (A) to the brain stem (B) (asterisks).

C, Axial T2-weighted image (2100/90/2) at pontine level shows symmetrical pyramidal involvement (arrowhead).