A case of hemichorea occurring after intravenous alteplase middle cerebral artery recanalization

Abstract

An 86-year-old woman was admitted to our hospital with impaired consciousness and right hemiplegia. We diagnosed her with left MCA occlusion and administered intravenous alteplase (rt-PA). Her condition improved immediately thereafter, and left MCA recanalization was observed by magnetic resonance angiography. However, she developed hemichorea on the fifth day of hospitalization. Cranial magnetic resonance imaging showed no lesions in the left corpus striatum, and ¹²³I-N-isopropyl-p-iodoamphetamine single-photon emission computed tomography revealed decreased blood flow in the left MCA and the left putamen. We treated her with haloperidol and the hemichorea immediately improved. Seven cases to date have been reported of hemichorea and hemiballismus caused by MCA recanalization. We suspected that the hemichorea associated with hypermetabolism within the contralateral basal ganglia after recanalization might affect the cortico-basal ganglia loop. We must recognize that t-PA recanalization may cause hemichorea.