Acute pseudobulbar mutism due to discrete bilateral capsular infarction in the territory of the anterior choroidal artery

Abstract

Pseudobulbar mutism is rarely attributed to bilateral discrete posterior limb internal capsule-medial globus pallidus infarction. Few cases of bilateral anterior choroidal (AchA) artery territory infarction have been reported. We present 8 patients with ischaemic stroke in this location and vascular distribution who have a characterizable syndrome. All had the abrupt onset of inability to speak, swallow or phonate, accompanied by varying degrees of facial diplegia, hemiparesis, hemisensory loss, lethargy, neglect and change in affect. The appearance of clinical signs depends upon the presence of a new infarct contralateral to an older lesion in mirror position. The pathogenesis and progression of neurological deficit appears to be intimately related to hypertension. The role of intrinsic intracranial vascular pathology related to diabetes mellitus, embolism of cardiac origin and atherosclerosis is currently undefined. The prognosis for recovery is poor. Half of our patients died within a year of onset of symptoms. Capsular pseudobulbar mutism is recognized by the abrupt appearance of neurological deficit consistent with internal capsular pathology and is confirmed by CT scan or MRI.