In the last print edition of Neurosciences News, you learned about deep brain stimulation (DBS) surgery and how University of Minnesota researchers are working to make it safer for patients.
The FDA already has approved the therapy to treat Parkinson’s disease and essential tremor, and it has also granted humanitarian device exemptions for treating dystonia and obsessive compulsive disorder.
But University experts believe DBS can do more for more people.
For example, DBS could be a good treatment for the one-third of epilepsy patients who don’t respond to anti-seizure medication, says University neurology professor Thomas Henry, M.D.
When medications cannot control seizures, an alternative therapy involves surgically removing a small part of the brain that is responsible for the seizures—if the surgery won’t significantly impair other critical brain functions such as cognition, language, and memory.
Epilepsy surgery is an excellent option for some of that third of epilepsy patients who don’t respond to medication, Henry says. But the surgery cannot be offered to other patients for a variety of reasons, such as if seizures begin too close to brain areas that are essential to movement or cognition or if seizures begin independently on both sides of the brain.
That’s where DBS comes into play, Henry says. The treatment delivers a “counter shock” to the brain to control seizures, and surgeons can implant electrical lead wires (controlled by a single pacemaker-like device) in both sides of the brain—leaving the organ fully intact.
Using DBS to treat epilepsy is currently under FDA consideration. Henry believes it’s the leading experimental therapy for the disease.
“We have the technologies,” he says. “Now we need to do the research. So I think we’re partway there.”
The University is also joining a clinical trial to examine whether DBS could help people who have severe depression. University neurosurgeon and associate professor Aviva Abosch, M.D., Ph.D.—who will co-lead the University’s portion of the trial with psychiatrist Barry Rittberg, M.D.—hopes to begin enrolling patients who have severe depression for which first-line therapies such as counseling and medication haven’t been effective by the end of the summer.
Other researchers around the country are exploring “a long list” of conditions that might be treatable with DBS, says Jerrold Vitek, M.D., Ph.D., a leader in the field and chair of the University’s Department of Neurology. That list includes addiction, schizophrenia, obesity, Alzheimer’s disease, autonomic nervous system disorders, autism, and Tourette syndrome, among others.
So what do these conditions have in common that makes DBS a potentially viable treatment option for all of them?
“The commonality of all of these conditions is that they are network disorders,” explains Abosch, meaning that they disrupt networks of brain cells responsible for essential functions such as movement, memory, and mood, for example.
The electrical stimuli delivered by DBS change the pattern of activity in the brain to improve those functions and restore the way that information should be transmitted to the body, Vitek says. He believes the therapy could have major implications in the future.
“Anything that is a circuit disorder could be amenable to deep brain stimulation,” he says.