A 9-YEAR-OLD GIRL presented with a 5-day history of a mild frontal headache. She had undergone a craniotomy 1 year earlier for a right frontal and intraventricular low-grade astrocytoma. At surgery, a right ventricular shunt was placed for hydrocephalus. Two months postoperatively, the shunt-dependent child required shunt revision for a loculated right lateral ventricle. The patient was receiving no medications, had no recent history of trauma, and was doing well in school.