Correlation of EEG, computerized tomography, and clinical findings. Study of 100 patients with focal delta activity

One hundred consecutive patients with continuous, focal, polymorphic delta activity on EEG who were also studied by computerized cranial tomography (CT) were reviewed. Sixty-eight percent showed focal structural lesions on CT, with stroke being the most frequent etiologic factor. Tumors occurred less often and trauma more frequently than in previous studies. Convulsions were the most frequent cause of focal delta activity with a normal scan.