Clinical question: 17-year-old male with Chiari malformation. Status post shunt placement. Now with mental status change, concerned for stroke. Signs and symptoms: Altered mental status. Non-enhanced CT of brain:A catheter traversing the midline at the level of the foramina magnum and enters the foot ventricle which is nearly completely collapsed. The catheter extends superiorly to the level of quadrigeminal plate. This is believed to be within the aqueduct. No change since prior exam.Images through supratentorial space demonstrate normal size of lateral ventricles and with no change since prior examination. There is no evidence of intracranial hemorrhage, edema, mass effect, midline shift or hydrocephalus. Cortical sulci, ventricular system and all CSF cisterns remain within normal.Two punctate area of subcortical low attenuation symmetrically and bilateral posterior frontal lobes are again identified and are believed to represent prominent perivascular spaces as were noted on prior MRI exam.
No evidence of acute new findings and stable exam since prior study.