[Progressive cerebral infraction initially presenting with pseudo-ulnar nerve palsy in a patient with severe internal carotid artery stenosis].

A 63-year-old man with hypercholesterolemia developed sensory and motor disturbances in the ulnar side of the right hand, and over three days the weakness evolved to entire right arm. Examination on the 6th day after onset showed mild lower facial palsy in addition to the upper limb weakness on the right. The weakness involved entire right arm sparing shoulder girdle muscles, which was worse in the 4th and 5th digits with claw hand deformity of the hand. Magnetic resonance imaging showed multiple small infracts in the centrum semiovale as well as in the medial side of the precentral knob on the left. Magnetic resonance angiography, ultrasonography, and 3D-CT angiography of the neck showed severe stenosis associated with unstable plaque of the left internal carotid artery. Hemodynamic mechanisms including microemboli and hypoperfusion associated with severe internal carotid artery stenosis are likely to cause stroke in evolution after initial presentation of pseudo-ulnar palsy in the present case.