Subcortical arteriosclerotic encephalopathy: brain stem findings with MR imaging.

Magnetic resonance images of 44 patients who had varying degrees of supratentorial signal abnormalities compatible with subcortical arteriosclerotic encephalopathy (SAE) were reviewed for posterior fossa findings. Brain stem lesions frequently accompanied supratentorial SAE and were seen as multiple, fairly symmetric areas of poorly defined, increased signal intensity on axial T2-weighted images. Involvement was generally confined to the central portions of the mid and upper pons. The typical appearance of brain stem involvement by SAE and its probable pathogenesis are reviewed.