False positive-false negative CT scan in late epileptic seizure: a meningioma-glioblastoma association.

A false-negative finding on initial CT is reported in a case of supratentorial glioma. This observation was peculiar because the first CT revealed a meningioma which might initially have been related to the clinical symptoms. The term false positive-false negative CT is proposed. The reasons for such CT failures are discussed. The accuracy of clues as to the localization of the glioma provided by EEG is emphasized.