NEW ORLEANS – Stimulation of a specific area of the posterior hypothalamus reduced and reversed aggressive behavior, according to a case series of two patients presented at the annual meeting of the American Association of Neurological Surgeons.
Giovanni Broggi, M.D., professor and chairman of the department of neurosurgery, Istituto Tumori Besta, Milan, Italy, reported results of stimulation in two patients.
Surgery on the posterior hypothalamus was first attempted and reported in the 1960s, said Dr. Broggi. But it was not widely accepted, as there were concerns about inducing irreversible damage. At his institute in Milan, Dr. Broggi and his colleagues have used chronic stimulation of the area to help treat intractable pain in cluster headaches.
Some have observed that patients with these headaches sometimes engage in aggressive behavior, said Dr. Broggi.
Extending the potential use for stimulation, Dr. Broggi and his colleagues implanted stereotactic bilateral electrodes in the medial portion of the triangle of Sano in two patients who had been institutionalized for psychosis with aggressive behavior. Stimulation was begun one day after surgery to implant the electrodes.
One patient, aged 34 years, had intractable epilepsy in addition to aggressive behavior and had been sedated for 4 years.
After surgery and stimulation, the patient had a 50% decrease in seizures and went home to live with his family.
The other patient's aggressive behavior also resolved, said Dr. Broggi.
At 1 year after implantation, both patients continued to do well. There were no acute or long-term side effects, he said.
Dr. Broggi said he would continue to investigate deep-brain stimulation to control aggression, noting that it had been proved as a reversible, safe surgical method in Parkinson's disease.
In discussing the paper at the meeting, Aviva Abosch, M.D., of Emory University, Atlanta, said that stimulation could be an option for truly medically refractory patients. “The changes described are dramatic,” but, she added, the report was lacking many details, such as whether the device was ever turned off, and if so, if the aggression returned. Dr. Broggi also did not report on any monitoring or testing that might describe any side effects, she said.
Use of deep-brain stimulation to control aggression raises many ethical questions because it could be considered psychosurgery, said Dr. Abosch.