Dopaminergic deficiency syndrome in the picture of severe brain injury in the presence of protracted depression of consciousness

Abstract

Objective: to determine the clinical and electroencephalographic (EEG) signs of dopaminergic deficiency (DD) when recovering consciousness in patients with severe brain injury (SBI).Patients and methods. Thirty-five patients (23 men and 12 women; mean age 29±13 years), who had experienced SBI accompanied by coma (mean duration 17±6 days) and treated at the Acad. N.N. Burdenko Research Institute of Neurosurgery, were examined. The comprehensive examination included neurological and mental status evaluation and EEG with dynamic assessment of the pattern.Results and discussion. The authors defined a constellation of neurological symptoms as increased extrapyramidal muscle tone, resting tremor, and specific autonomic dysfunction, which was characteristic of autonomic status and some forms of mutism, and, in accordance with the data available in the literature, was defined as DD syndrome. The latter accompanied by characteristic EEG changes: its pattern’s higher synchronized β-activity (13–14 Hz) enhanced in the frontal and anterior temporal regions. The administration of amantadine sulfate was followed by an increase (even as compared with the normal value) in the dynamics of the power of mainly of β3 (at frequencies of 17–23 Hz) and θ2 (5.9–7.4 Hz) bands along the anterior regions more frequently on the right; by the amplification of intrahemispheric connections (in the occipitotemporal regions) in the β3 band (more often on the right) and θ one (5.9–7.4 Hz) in the right occipitotemporal region. The agent had no significant effect on the SBI outcome assessed 12 months after injury, but it affected the clinical symptoms of DD.

Keywords

• dopaminergic deficiency syndrome
• dopaminergic system
• electroencephalography
• severe brain injury
• neurotransmitters
• amantadine sulfate