A 76-year-old hypertensive man was admitted with an acute left ataxic hemiparesis. Neurological examination found a left-sided hemiparesis and cerebellar ataxia without proprioceptive impairment (admission National Institute of Health Stroke Scale score = 4). Diffusion-weighted imaging disclosed a lacunar ischemic lesion within the right ventroposterolateral thalamic nucleus and an equivocal signal within the right cerebral peduncle. No significant cerebellar or temporo-occipital involvement was observed. Basilar and right posterior cerebral artery occlusions were found on magnetic resonance angiography. Perfusion-weighted imaging was performed with gradient-echo echoplanar imaging using the bolus passage-of-contrast method. The time-to-peak map, generated from the concentration time curve, confirmed an extensive perfusion delay in posterior fossa and right posterior cerebral artery territory, with a nearly complete diffusion-weighted imaging–perfusion-weighted imaging mismatch (Figure). The patient was treated with intravenous tissue plasminogen activator, administered 155 minutes after symptom onset. Outcome was favorable, with only mild left upper limb ataxia. The patient was discharged on day 3 (National Institute of Health Stroke Scale score = 1).
Cho T, Hermier M, Derex L, Trouillas P, Nighoghossian N. Ataxic HemiparesisThe Benefit of Acute Multiparametric Magnetic Resonance Imaging. Arch Neurol. 2010;67(1):116-117. doi:10.1001/archneurol.2009.300