Correlation between Clinicoradiological Findings and Prognosis in Paramedian Pontine Infarction

ABSTRACT

BACKGROUND: To clarify the clinicoradiological correlation and prognosis of acute ischemic stroke involving para-median territory of pons. METHODS: We studied 37 patients with first-ever ischemic stroke involving paramedian terri-tory of pons and divided them based on the shape and level of lesion shown in their MRI. The clinical features, MRI findings, and prognosis were assessed. RESULTS: The paramedian infarctions extending to the basal surface were found in 28 patients (76%), and small infarctions separated from the basal surface were found in 9 patients (24%). In patients with infarction extending to the basal surface, 23 patients (82%) had progressive or fluctuating onset, whereas all patients with small infarction separated from the basal surface had non-progressive onset. In the group with upper pon-tine lesion (14 patients), dysarthria-clumsy hand syndrome was found in 4 patients, ataxic hemiparesis (AH) in 3, pure motor hemiparesis (PMH) in 2, and pure sensory stroke in 1. In the group with middle and lower pontine lesion (22 patients), PMH was found in 9, AH in 3, and sensory motor stroke in 2. The mean Modified Rankin Disability Scale scores on admission and after follow-up (mean 29 months) of the group with upper pontine lesion were 2.36 +/-0.50 and 1 . 0 0 +/-0.55, those with mid-lower pontine lesions, 3.48 +/-0.51 and 1.17 +/-0.49 (P0.05 respectively). CONCLUSIONS: Paramedian pontine infarction extending to the basal surface usually presents with progressive onset. Paramedian pontine infarction most often produces classic lacune syndrome of which PMH is the most common. In our study, patients with mid-lower paramedian pontine infarction had more severe initial neurological deficits than those with upper paramedian pontine infarction. However, a late outcome was found to be favorable in both groups.