抄録
Patients with acute epidural hematoma (AEH) may develop cerebral dysfunction secondary to compression of normal brain by the extracerebral mass. Fifty-four patients who developed AEH within 3 days of head trauma were studied in terms of the relationship between neurological symptoms and hematoma volume. The hematoma volume was measured by semiautomatic analysis of computed tomographic (CT) scans. The volume V (ml) was roughly estimated by the formula: V=2π (5.5d2 d3/3), where 2d (cm) represents the maximum thickness. Disturbance of consciousness and hemiparesis developed as the hematoma volume increased. Beyond 6 hours after trauma, patients with an AEH below 55 ml in volume had little or no disturbance of consciousness, whereas those with an AEH of more than 70 ml had hemiparesis and impaired consciousness with Glasgow Coma Scale scores 12 or less. Descending tentorial herniation was demonstrated by CT in cases where the AEH was greater than 50 ml, and advanced herniation was observed when the AEH exceeded 150 ml. Nearly all of the patients with uncomplicated AEH showed good recovery within 6 months following evacuation of the hematoma; however, those whose hematomas were over 140 ml had poor outcomes.