PET data were compared with the results of computerized tomography (CT) and the neurological status of patients. The areas of decreased local cerebral blood flow (LCBF) and reduced local cerebral metabolic glucose rates exceeded those of brain injury shown by CT predominantly in patients with brain posttraumatic cysts. In a group of patients with posttraumatic atrophy documented by CT, PET demonstrated cortical and/or subcortical lesions in most cases, providing objective evidence for neurological symptoms. PET is a useful technique to demonstrate regional brain dysfunction in the presence of morphological integrity as assessed by CT.