Among the more than 500 patients who have undergone deep brain stimulation (DBS) — the implantation of a “brain pacemaker” and electrodes to ease symptoms of movement disorders — one of the common observations is that “they wish they had done it earlier,” says Nader Pouratian, MD, director of UCLA’s Neurosurgical Movement Disorders Program.
In the United States, an estimated 10-million people have essential tremor and 1 million have Parkinson’s disease. While DBS does not cure or change the trajectory of either disease, it is a safe and effective procedure that provides symptomatic relief to many patients, Dr. Pouratian says. The procedure has most recently been approved for two more conditions, dystonia (characterized by involuntary muscle contractions) and obsessive-compulsive disorder. It is also being studied for its potential to help in a number of other conditions.
In DBS, electrodes are strategically placed in the brain while a battery-powered generator is implanted in the chest to emit continuous pulses, correcting the abnormal patterns of brain activity for patients with neurological disease.
The surgery is most commonly performed as an asleep-awake-asleep procedure. The patient is asleep and anesthetized at the start of the procedure and awakened after the brain is exposed so he or she can respond to verbal commands with feedback that assists the surgical team in optimal placement of the electrodes. Afterward, the patient is put to sleep again as the final stage of the operation is completed. Since there are no pain receptors within the brain, patients experience no discomfort while awake during the operation.
The goal of DBS “is to improve function and quality of life,” Dr. Pouratian explains. That is best achieved by being able to interact with the patient during surgery “to make sure we’re getting the benefits from the stimulation while limiting the side effects,” he says. “If the electrode is not in the optimal position, that’s our opportunity to move it.” However, for patients who are uncomfortable with the idea of being awake, the surgery can be performed under image guidance while they remain asleep throughout, Dr. Pouratian says.
Medications remain the first treatment option for movement disorders and can be effective in many patients. But patients who either don’t receive satisfactory benefits from their drugs or who experience intolerable side effects should be evaluated to determine whether DBS is an option, Dr. Pouratian says. At UCLA, a patient-centered approach features a multidisciplinary team, with the neurosurgeon and neurologist Yvette Bordelon, MD, working closely together before, during and after the surgery.
“We have excellent large, long-term studies showing that overall, those who are candidates for the surgery experience significant improvement in their quality of life, well beyond what patients receive from the available medications,” Dr. Pouratian says. “This is not a cure, but it’s quite clear that patients spend much more of their day in a better condition — able to participate in many more activities and to enjoy their lives more.”