ABSTRACT
A stystematic neurological and electroencephalographical follow-up study in 344 head injured adults gave the following results: 1. 52% of all the hospitalized (mostly primarily amnesic) patients had a cerebral contusion. A contusion was assumed in cases with focal neurological signs (13%), amnesias of more than 8 hours (16%) and/or EEG-abnormalities lasting for more than 24 hours (49%). 2. Traumatic EEG-abnormalities were general slowing (43%) and foci (32%). In 40% of the cases with general slowing the slowing (greater than or equal to 1.5/sec) was within the alpha-frequency band and could only retrospectively be assed. 3. The EEG was invariably abnormal in cases with an amnesia exceeding 8 hours. If the amnesia exceeded 1 hour abnormalities were found in 73%. 4. Among the patients with contusion 6.5% had no amnesia, 48% less than 30 minutes and only 30% an amnesia for more than 8 hours. In 75% of the patients with concussion amnesia lasted less than one hour. 5. Skull fractures were mostly combined with contusion (74%). 6. Impaired drive, reduced ability to concentrate, memory deficits, headache and dizziness were significantly more frequent 6 months after contusion than after concussion. 7. 21% of the patients with traumatic dizziness (44%) had a labyrinthine contusion. 8. Among the contusions diagnosed with the aid of EEG recordings 58% would have been missed after exclusive neurological examination and 82% after application of the classical criteria used by surgeons and general practitioners.
