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.