Isolated Infarction of the Medullary Pyramid - A Rare Pure Motor Stroke

Abstract

Acute pure motor hemiparesis can occur due to a vascular insult along the cortico spinal pathway. Rarely such a stroke can occur as a result of involvement of the pyramids located on the ventral aspect of the medulla. Neurological localization can be difficult in such strokes and moreover they can also pose imaging challenges since they are missed on the CT scans. So far only 4 such cases have been reported in literature. Here we present two cases of pure motor strokes caused by infarction of the medullary pyramids. We have described the anatomical correlates of the symptoms and signs and also highlight the importance of MRI in picking up these rare strokes.

Keywords: Corticospinal tracts; Hemiparesis; Hypoglossal nerve; Medullary strokes; Pure motor strokes; Pyramidal infarction.