Clinical Significance of T2 Sagittal Image and the Flow Void of Basilar Artery in Pontine Infarction

ABSTRACT

BACKGROUND: Pontine infarction extending to the basal surface has been reported to possess different characteristics from deep pontine infarction without extending to the basal surface. METHODS AND RESULTS: We studied 54 patients ; 30 patients with pontine infarction extending to the basal surface (group SE) and 24 patients with deep pontine infarction without extension (group DL) based on the site of the infarcts on precontrast sagittal T2WI. We assessed angiographic findings(MRA, 54; DSA, 31), risk factors, clinical features and the effectiveness of the intraluminal signal changes on spin-echo MRI in the diagnosis of occlusion or stenosis of the basilar artery. The incidence of basilar artery stenosis or occlusion in MRA or DSA in group SE(60%) was significantly more frequent than group DL(12.5%), whereas the incidence of vertebral artery stenosis or occlusion was not different between two groups. A noteworthy finding was that five patients (17%) of the group SE had not been extended to the basal surface on axial T2WI. The risk factors were similarly distributed between the two groups. The effectiveness of abnormal signal void of axial MRI was poor in the diagnosis of basilar artery occlusion or stenosis. CONCLUSIONS: Our results suggest that the two types of pontine infarction may be caused by different arterial pathology. Although the presence of abnormal flow void on MRI cannot predict the stenosis or occlusion of basilar artery, sagittal T2WI and angiographic study help to evaluate the patients with pontine infarction.