A Statistical Study on Routine Clinical EEG Findings in 5,000 Cases

Abstract

Abnormal EEG findings at the time of initial examinations--paroxysmal abnormal findings in particular--were studied. 1. Paroxysmal abnormal findings were found in 266 patients with epilepsy, 67 patients with head injury, 29 patients with headache as chief complaint and 82 patients with other disorders in a total of 444 patients (8.9% of all patients examined). 2. Paroxysmal patterns were found only in 266 patients with epilepsy, corresponding to 40.2% of the 661 patients with this disorders on whom EEG was performed. When paroxysmal patterns are not found at the time of initial tracing suspected of epilepsy in a patient clinically, EEG should be repeatedly traced, both routine EEG and the activation with pentetrazol, bemegride, monosodium trichlorethyl phosphate or other drugs. 3. The incidence of paroxysmal patterns in patients with head injury of Araki II to IV types were significantly higher than those in patients of Araki I type (p<0.005). 4. The subjects of this study included as many as 1,634 patients with head injury, corresponding to 32.7% of all subjects, and it appears that the social situation in which traffic accidents and labor hazards have recently been on the increase, reflects this high incidence of head injury.