Deep Brain Stimulation (DBS) is a relatively new treatment for a number of neurological conditions, including essential tremor, dystonia, and Parkinson’s Disease. DBS was FDA approved in 1997. Research into DBS’s potential applications continues, but already evidence suggests that DBS may be useful for the treatment of other conditions, including:
- Cluster headaches
- Epilepsy (epileptic seizures)
- Chronic pain
- Tourette syndrome
- Major depression that isn’t adequately controlled by medication
DBS is particularly promising for the treatment of Parkinson’s Disease, which affects hundreds of thousands of Americans. Parkinson’s Disease can severely impact the quality of life over the course of its progression over many years. While DBS can’t cure the disease or reverse neurodegenerative processes, it can measurably improve quality of life for patients with moderate Parkinson’s symptoms. The benefits of DBS have been shown to be sustained over at least 5 years in a randomised controlled trial. On average patients experience 5 more hours of “ON time” following DBS.
DBS Is Like a Pacemaker for Your Brain
It’s helpful to think of DBS treatment as a pacemaker for your brain. In fact, the treatment does involve a pacemaker device that is broadly similar to the devices used to treat arrhythmias and other heart problems.
According to the National Institutes for Health, “DBS uses a surgically implanted, battery-operated medical device called an implantable pulse generator (IPG) – similar to a heart pacemaker and approximately the size of a stopwatch – to deliver electrical stimulation to specific areas in the brain that influence movement, thus blocking the abnormal nerve signals that cause PD symptoms”. Some researchers compare PD to having the brakes in a car intermittently stuck on. DBS can reduce this effect.
The DBS “pacemaker” is typically implanted underneath the skin in the patient’s upper torso in an initial surgery. In a second surgery, the device is connected by a thin, flexible wire to an electrode implanted in the brain.
To determine the ideal location for the electrode, the surgical team uses both magnetic resonance imaging (MRI) and computed tomography (CT) imaging. In some cases, a technique known as microelectrode recording, which uses a small wire to monitor and record the activity of small groups of nerve cells, is employed as well. Although the precise region varies patient by patient, DBS electrodes are typically implanted in these locations:
- The globus pallidus
- The thalamus
- The subthalamic nucleus
DBS procedures usually involve one or two electrodes. The electrodes influence the function of the opposite side of the body. Patients with symptoms affecting both the right and left side often receive bilateral implants.
An electrode’s tip is positioned in the appropriate brain region and begins delivering impulses generated by the pacemaker-like device. These impulses block abnormal brain signals caused by the progression of Parkinson’s Disease, improving brain function and reducing the impact of Parkinson’s symptoms.
DBS changes neural firing patterns in the brain, and not the underlying causes of abnormal firing patterns or the overall progression of neurodegenerative disease. This is similar to the way in which a pacemaker corrects abnormal heart rhythms without curing or improving the underlying causes of those rhythms.
Is DBS Right for You?
DBS offers promise for the treatment of Parkinson’s Disease. When used properly in the right candidates for the procedure, DBS can meaningfully improve brain function and reduce certain Parkinson’s symptoms.
As with all surgical treatments for serious neurological conditions, however, it’s important to keep DBS’s benefits in perspective. The procedure requires two separate surgeries. All surgical procedures have risks. Although adverse surgical outcomes are uncommon, candidates and their families need to understand these risks. Possible side effects and surgical complications include:
- Post-surgical infection
- Device breakage or malfunction
- Movement of the device(s) in the body and brain
Although an accurate determination of one’s suitability for DBS intervention is only possible after a thorough, in-person evaluation of the candidate’s symptoms and risk profile, good DBS candidates generally:
- Exhibit symptoms that are no longer adequately controlled by medication
- Experience long “off” stretches, during which motor function and control are severely impacted
- suffer from frequent “on – off” fluctuation
- experience debilitating dyskinesia, often made worse by medication
- suffer from frequent freezing
- Have not progressed to the point that dopamine has little to no effect
- Do not exhibit signs of dementia or cognitive loss
- Are not being treated for severe depression
- Are not being treated for a condition that requires future MRIs
A Treatment, Not a Panacea
DBS candidates and their families need to understand that while DBS is a promising treatment for Parkinson’s Disease and certain other neurological conditions, it’s not a panacea.
We tell our patients that they should never expect to feel better than their best “on” day, even with DBS. DBS doesn’t reverse the progression of Parkinson’s Disease or improve function during “on” periods. Rather, DBS simply extends the length of the “on” period and allows patients to take full advantage of the function that they enjoy during this time.
After DBS surgery, patients should begin to see immediate effects. However, we typically continue to consult with patients, at decreasing frequencies, in the months following the procedure. These consultations allow for the adjustment of the pacemaker device’s signal strength and stimulative effects, as well as medication dosing.
Finally, DBS is indicated only for classic Parkinson’s Disease, and not for Parkinsonian (sometimes called Parkinson’s Plus) conditions that present some of the same symptoms of classic PD, but tend to have different (often more aggressive) progressions, causative factors, and treatment options. If you’re facing a Parkinson’s-like condition, ask your physician or holistic treatment professional about options that apply specifically to your situation.