Theta Pattern Coma, a Variant of Alpha Pattern Coma

Abstract

Electroencephalograms with a dominant rhythmic areactive 5Hz theta activity are reported in two comatose patients with fatal outcome. This pattern was followed by isoelectric EEG and death in the first patient, who suffered multiple injuries including severe cerebral concussion and later tentorial herniation. The second patient died eight hours after the second EEG recording, both EEGs having shown a very rhythmic 5-6 Hz activity which was maximal anteriorly. He died two days after a severe cerebral hypoxic episode due to acute respiratory failure. Both patients were in their late sixties. It is suggested that the dominant areactive theta activity is a variant of malignant "alpha pattern coma".