CT and MR Imaging Features of Pyogenic Ventriculitis

BACKGROUND AND PURPOSE: Pyogenic ventriculitis is an uncommon manifestation of severe intracranial infection that might be clinically obscure. We hypothesized that determining characteristic imaging features of pyogenic ventriculitis in patients with appropriate risk fac-tors might improve recognition of this severe infection. METHODS: Review of the medical records from 1990 to 2000 revealed 17 cases (12 men, five women) that satisfied inclusion criteria of abscess (n 5 3) and/or positive cultures or increased white cells and protein in ventricular (n 5 12) or cisternal (n 5 1) cerebrospinal fluid. In one case, the diagnosis of ventriculitis was based on the combination of bacterial growth in lumbar cerebrospinal fluid and follow-up imaging. Staphylococcus species and En-terobacter species were the most common organisms. Two neuroradiologists independently eval-uated imaging studies for hydrocephalus, ventricular debris, periventricular attenuation or signal abnormality, ependymal enhancement, and signs of meningitis or abscess. Sixteen studies in 11 patients were performed after the intravenous administration of contrast material