[Pontine infarction presenting non-paralytic pontine exotropia--evaluation of its clinical course and its MRI findings].

We report two patients with brainstem infarction who presented non-paralytic pontine exotropia (NPPE) in acute phase. Case 1 was a 76-year-old woman. NPPE observed 3 hours after the onset disappeared two days later. Case 2 was a 60-year-old man. Paralytic pontine exotropia was observed 4 hours after the onset of his stroke. NPPE was noted on the next day and left medial longitudinal fasciculus (MLF) syndrome was still present on the third day. Seven days later, the disturbances of ocular movement was disappeared. T2-weighted cranial MRI showed high signal intensity lesions in the paramedian portion of the mid-pontine tegmentum beneath the fourth ventricle in both cases. Although it has been thought that NPPE is a rare clinical symptom, we think that NPPE is by no means a rare symptom in the acute stage of brainstem infarction.