A Steady Hand: Deep Brain Stimulation for Essential Tremor
For patients with essential tremor, deep brain stimulation treatments can be life changing.
Mary Unkel has had quite a life. Vice president for an East Coast advertising agency. Head of her own company serving nonprofits. Even a classical pianist. And through much of it, she has contended with essential tremor, a neurological disorder that affects muscle movement, most commonly in the hands. She first noticed it 37 years ago, in the middle of a client presentation.
“I didn’t know what was happening,” Mary said. “Everyone, including me, thought it was the stress. But it wasn’t. It would come and go and got progressively worse.”
Deep Brain Stimulation
In 1994, Mary and her husband, Bob, relocated to Wisconsin for his job. As time went by, her condition advanced markedly. It was a challenge to hold a cup of coffee without spilling it and she could barely write her name. Plus, she was experiencing dystonia, involuntary spasms of the vocal cords that make speaking clearly difficult. In 2014, she made an appointment with Karen Blindauer, MD, neurologist, movement disorders specialist and Medical College of Wisconsin faculty member.
“We began by using medication to control the tremor,” Dr. Blindauer said. “Over time, she was not getting any substantive benefit from the medication, so we proposed a surgical intervention — deep brain stimulation.”
Deep brain stimulation, or DBS, involves placing one or more electrodes in the brain and connecting them to a device called a neurostimulator that is implanted in the chest. The neurostimulator is then programmed to deliver electrical signals to help control abnormal brain activity. Most patients with essential tremor experience a 70%-80% reduction in their tremor. DBS is also used to treat the symptoms of Parkinson’s disease.
“The electrode has four different active contacts that are separated by a couple of millimeters, allowing us to stimulate slightly different locations in the brain,” Dr. Blindauer said. “In the part of the thalamus we target to suppress the tremors, stimulating a certain area could worsen coordination or speech. We have to pick the contact that suppresses the tremor, but doesn’t cause any of those effects.”
Comprehensive Evaluation for DBS
Mary was open to the idea of DBS, but said getting it was no slam-dunk. Like all patients seeking the treatment, she had a thorough pre-op work-up, which included an evaluation from Alissa Butts, PhD, neuropsychologist and MCW faculty member.
“We test a patient’s cognitive functioning — memory, problem-solving, language skills,” Butts said. “People who have significant cognitive impairment prior to DBS are at higher risk for experiencing further decline after the procedure. While this is not a psychiatric evaluation, we do assess the patient’s emotional well-being and quality of life before proceeding to ensure we are setting them up for a good outcome.”
DBS Surgery and Follow-Up
Mary was cleared for surgery, and in August 2022, electrodes were implanted in her brain by Peter Pahapill, MD, PhD, neurosurgeon and MCW faculty member, and Ryan Brennan, DO, neurologist and MCW faculty member. DBS patients need to be able to communicate with the physicians during the surgery, so only a local anesthetic is used to numb the scalp where the surgeon makes a small opening. Using computerized technology, the medical team then tracks brain activity and targets areas where the electrodes need to be implanted.
A week later, under general anesthesia, Mary’s neurostimulator was implanted. Shortly afterward, Dr. Blindauer programmed the device.
“Over time, the tremor can change, requiring an adjustment in the frequency or amplitude of the electrical signal,” Dr. Blindauer said. DBS patients receive a handheld programmer that allows them to check the neurostimulator status, monitor battery life, turn the therapy on or off, and make small adjustments preset by their doctor.
While tremor can affect both sides of the body, doctors begin by addressing a patient’s dominant side — in Mary’s case that was her right hand.
“If a person needs two steady hands to do activities or to have the quality of life they are aiming for, we’ll perform surgery on each side of the brain,” Dr. Blindauer said. “Generally, patients are satisfied with surgery on one side.”
That has been Mary’s experience. After the initial programming, she was able to drink from a cup using one hand and was able to write again.
“We were targeting the hand tremor, but Mary even had some improvement in her ability to speak,” Dr. Blindauer said. “She has had a stellar outcome, above and beyond what we would hope for.”
For Mary, the outcome has been life changing.
“Dr. Blindauer has always listened intently and with compassion throughout my journey,” Mary said. “She has been my advocate and the quarterback of this amazing production. I can’t express strongly enough my appreciation for the life the team has given back to me.”
Our expert Neurosurgery and Neurology teams are skilled at helping people with movement disorders. For more information about DBS, visit froedtert.com/dbs.
See the Difference Before and After DBS
Mary provided us with these videos to show us what a difference DBS made in her day-to-day life.