For those individuals with Parkinson’s Disease (PD) who face medication-resistant symptoms, Deep Brain Stimulation (or DBS) can offer a renewed hope for some patients. Once considered a last resort, this surgical procedure is now a well-established treatment for eligible patients, helping to reduce severe symptoms and improve quality of life.
Understanding Parkinson’s and DBS
Parkinson’s disease affects more than one million people in the United States and millions worldwide. In its early stages, symptoms such as tremors and rigidity are often effectively managed with medication. However, as the disease progresses, some patients develop motor complications, including “on/off” fluctuations and dyskinesia, that medications alone can no longer control. Deep brain stimulation provides a more advanced alternative. Common symptoms improved by DBS include tremor, bradykinesia (slowness of movement), rigidity, and medication-induced involuntary movements. However, the procedure does not address balance issues, freezing of gait, speech problems, or cognitive decline. Typically, DBS allows for a reduction in medication, averaging 30 to 50 percent depending on the patient, but does not eliminate the need for medication entirely.
What is the process?
The first stage is usually an outpatient procedure: While under general anesthesia, the doctor will place small screws called fiducials at four points on the skull. These will serve as landmarks to guide the brain scans during the procedure. Combined with the patient’s previously taken MRI, these scans are used to precisely identify the target areas for lead placement. The surgeon also implants an Implantable Pulse Generator (IPG), a device that powers the DBS system, by making a small horizontal incision in the upper chest. The patient can choose which side to operate on, and the device is inserted beneath the skin. The brain leads will be connected to the IPG during the second stage of surgery.
The fiducials are left in place until the patient returns for Stage 2, when the leads are implanted into the brain. While most of the surgery is performed with the patient awake, the scalp is numbed with local anesthesia, and since the brain doesn’t feel pain, patients generally tolerate the procedure well.
First, the surgeon drills a dime-sized hole into the side of the skull. A customized frame created from imaging data during Stage 1 is secured to the head to keep the DBS lead stable throughout the operation. Using this guide, the surgeon carefully implants the lead into the targeted brain area. Once in place, stimulation is activated to assess symptom improvement and monitor for side effects. Any side effects during testing are temporary and cease once stimulation is turned off. The neurologist and surgeon work together to ensure optimal placement. After confirming correct placement, the surgeon secures the lead with bone cement, removes the frame, and takes out the fiducial screws. The lead remains implanted and will connect to the pulse generator placed during Stage 1.
Patients stay overnight in the hospital for observation, and there may be some discomfort around the chest incision. These effects usually subside after three to four weeks of recovery. A follow-up appointment is scheduled after a month to begin initial programming of the DBS.
Neurologists use advanced imaging and “on/off” medication testing to identify effective stimulation zones. Patients often receive a handheld controller to manage the DBS device at home, allowing basic adjustments as directed by their care team.
A Win For Some
Not everyone with Parkinson’s is a candidate for DBS. A comprehensive evaluation includes Medication Response Testing(also known as pharmacogenetic or pharmacogenomic testing, is the process of analyzing a person’s genes to predict how they will respond to certain medications) to confirm whether symptoms improve with medications, even temporarily. A Neurocognitive Assessment (a diagnostic procedure that involves the assessment of cognitive functions, such as memory, attention, language, and problem-solving skills. These tests are designed to evaluate brain function and identify potential cognitive impairments or disorders.) is also performed to check for memory or mood issues that could worsen with surgery, and MRI scans are used to guide surgical planning and ensure brain structure suitability. If someone has mental health challenges, memory loss, or dementia-like symptoms, it’s important to consult with their doctor first, as the risks can be higher in those cases.
Upkeep, Risks, and Safety Considerations
During the device’s lifetime, battery replacement will be needed. Doctors monitor battery levels and recommend replacement under general anesthesia, which takes less than an hour.
While DBS is generally safe, there are risks associated with the procedure that patients should be aware of. There is about a one percent chance of a brain bleed, which could result in neurological issues later. The risk of infection around the chest incision is approximately five percent, usually treatable with antibiotics. Rarely, removal and replacement of the DBS implants are necessary if complications arise. Some patients might experience mood changes, and in rare cases, seizures can occur shortly after the procedure. Fortunately, these effects typically resolve on their own within a few weeks or months.
Important warning: although rarely used today, a treatment called diathermy—used in physical therapy—can dangerously heat DBS leads. It must be strictly avoided, as it can cause severe complications like stroke or even death.
Deep Brain Stimulation can significantly improve the quality of life for some Parkinson’s patients, but it isn’t a cure. Regular follow-up with your physician for neurological assessments and device maintenance enables patients to maintain a fairly normal life with minimal restrictions. For those who qualify, DBS can mean the difference between merely coping with Parkinson’s and regaining meaningful control over life.
Contact your neurologist or a movement disorder specialist to learn more about deep brain stimulation and whether it may be right for you.
AI generated photo by Adobe for Chris Denny