MRI pontine hyperintensity after supratentorial ischemic stroke relates to poor clinical outcome

Abstract

Background and Purpose - MRI studies in patients with atherosclerosis often reveal ill-defined hyperintensity in the pons on T2-weighted images. This pontine hyperintensity (PHI) does not fulfill the criteria of a brain infarct, and its clinical relevance is not established. We examined the frequency, as well as the radiological and clinical correlates, of PHI in poststroke patients. Methods - Three hundred nineteen patients were studied 3 months after supratentorial ischemic stroke with the use of 1.0-T MRI. Brain infarcts, atrophy, white matter hyperintensities, and PHI were registered. The clinical outcome was assessed 3 and 15 months after the stroke. Results - Of the patients, 152 (47.6%) had PHI. The risk factors for stroke did not differ in patients without or with PHI. PHI was related to a higher frequency (P=0.002) and larger volume (P<0.001) of supratentorial brain infarcts, to parietal (P=0.020) and temporal (P=0.002) atrophy, to central atrophy (P≤0.040), and to white matter hyperintensity grade (P<0.001). Brain infarcts that affected the corpus striatum (putamen, caudate, and pallidum) (P≤0.011) or pyramidal tract (P<0.001) were more frequent in patients with PHI. The 3- and 15-month outcomes were worse in patients with PHI (P≤0.004). The total volume of brain infarcts (OR 1.22), mean atrophy (OR 3.59), and PHI (OR 3.76) were independent correlates of a poor 15-month outcome. Conclusions - PHI after supratentorial ischemic stroke deserves attention because it relates to poor clinical outcome.