POSTTRAUMATIC AMNESIA - STILL A VALUABLE YARDSTICK

Records of coma and post-traumatic amnesia (PTA) were collected for a group of 38 patients with closed head injury. The results confirmed ea rlier studies indicating that patients may have short or negligible co ma but report prolonged PTA. Comparison of eight patients with prolong ed PTA (>7 days) and short coma (<6 hours) with the rest of the group on MRI in the acute stage showed that these patients had significantly more extensive hemispheric damage. In the group as a whole both coma and PTA were related to the number of areas in central brain structure s in which lesions were detected, but only PTA was significantly relat ed to the number of hemispheric areas in which lesions were found. It is concluded that although both coma and PTA are related to brain dama ge they reflect disparate patterns of lesions. Assessment of PTA can t hus provide additional information concerning severity of injury.