Acute midbrain infarction in a child with intracranial carotid artery hypoplasia and aberrant cerebral vasculature: a case report.

Strokes identified in older children typically present with sudden hemiparesis, frequent association with seizures, and occasional accompaniment of hemisensory signs or visual field defects. In this case of a left cerebral peduncle infarction, initially the patient was not found with evident right-side hemiparesis but with right-side paresthesia and mild worsening of her underlying left-side weakness, including weakness of left facial expression and left ptosis. Her right limbs became gradually weaker in the first 2 days. These bizarre clinical presentations, the mild worsening of the underlying left-side weakness, and the delayed presentation of right-side hemiparesis added to the difficulty of making a diagnosis and of the initial localization. In addition, the magnetic resonance angiography incidentally found an abnormal vessel, which was additional and serpiginous to the right posterior fossa. The right internal carotid artery was markedly smaller than the left one, and a defect was seen around the area of the presumed distal right internal carotid artery. The abnormal cerebral vasculature might be the cause of the unique clinical presentation and might be the contributing factor to the recurrence of her stroke. In conclusion, the authors report a special case of recurrent stroke on the basis of aberrant cerebral vasculature.