[The factors influencing posttraumatic epilepsy; multicentric cooperative study. Japan Follow-up Group for...

A multicentric cooperative study was performed to investigate the factors influencing posttraumatic epilepsy. The patients with fresh head injury from 1983 through 1990 were entered in this study. The cases were divided into two groups and followed-up for five years; the patients with severe head injury and who satisfied the criteria belonged to group I. Those with mild head injury were classified into group II. The criteria for group I was that the patients had one or more of the following risks; disturbance of consciousness, bloody cerebrospinal fluid, focal neurological sign, depressed fracture or basal fracture, abnormal CT, dural tear, early convulsion and/or linear fracture. After drop-out cases were excluded, 191 cases out of 241 were analyzed. The number of cases was 126 (66.0%) for group I and 65 (34.0%) for group II. Sixteen patients (12.7%) of group I developed seizure, whereas nobody of group II experienced seizure. The difference between the patients with and without seizures was analyzed. The statistical significant difference was discovered in the following factors; disturbance of consciousness (GCS and the duration), focal and generalized neurological sign, abnormal CT, multiple risks, intracerebral hematoma, surgery, alcohol drinking and abnormal EEG a month after the injury. The relative risk rates were calculated. The highest risk for posttraumatic seizure was disturbance of consciousness extending over more than one month. This was followed by five other indicators of risk; abnormal EEG at one month, surgery, focal neurological sign, alcohol drinking, generalized neurological sign, and intracerebral hematoma.(ABSTRACT TRUNCATED AT 250 WORDS)