Parkinson’s Disease (PD) is a complex neurodegenerative brain disorder where there is a depletion of dopamine, a neurotransmitter, in the brain. Dopamine is produced in an area of the brain called the substantia nigra and it helps to carry messages between neurons in the brain thereby regulating smooth coordinated movements.
In those with PD, there is a loss of dopamine-producing brain cells being produced in the brain. Therefore, neurons in the brain are not able to function properly leading to poor control of movements. It is often when one loses 60-80% of these dopamine-producing cells that PD symptoms are noticed. The loss of cells is described as neurodegeneration.
Symptoms of Parkinson's Disease
The most common symptoms of Parkinson’s Disease include:
- Tremor (shakiness)
- Rigidity (stiffness)
- Bradykinesia (slowness of movements)
- Postural instability (impaired balance and coordination)
Parkinson’s symptoms often progress gradually in most people and signs and symptoms vary among those who suffer from this disease. As the disease progresses, other symptoms, aside from those listed above, may be seen. These symptoms may include difficulty swallowing, trouble speaking, urinary incontinence, altered sleep, constipation, depression, and emotional changes. As the disease advances, cognitive decline may be seen.
There is no specific laboratory test or scan that can be done to diagnose Parkinson’s Disease. Along with the medical history of the patient, the neurological exam must have the presence of two of the three cardial signs of PD: tremor at rest, rigidity, and/or bradykinesias. The final diagnosis is made after ruling out all other potential causes of such symptoms such as certain medications causing symptoms or another disease process.
There is no cure for PD. At this time, there have not been any medications or treatments that have conclusively been shown to reverse the disease process. The initial treatment is medication that replaces dopamine deficit in the brain. There are other medications that also assist in alleviating the symptoms that one may experience with PD.
Deep brain stimulation has been a successful surgical treatment option for those that suffer from PD. DBS acts like a brain pacemaker. It releases high frequency electrical stimulation to a particular target area of the brain causing reorganization of the imbalanced neurotransmitters circuit thereby reducing the motor symptoms seen in PD. Again this is not a cure for the disease but a highly successful treatment option that alleviates some of the PD symptoms.
Is DBS Right for You?
There are 9 general criteria that we look for in a patient with Parkinson’s Disease to be eligible for DBS. They are as follows:
- Clear diagnosis of idiopathic PD: Patients with atypical Parkinsonism or "Parkinson’s plus" syndromes do not respond to DBS. Atypical Parkinson’s may include a very rapid progression of symptoms or early features of the PD including autonomic failure or postural instability. Surgery is contraindicated in these cases as well as those with signs of cerebellar or pyramidal dysfunction or an MRI suggesting an atypical syndrome.
- Intact cognitive function: Dementia is common in patients with Parkinson’s disease and often seen with advanced age and progression of disease symptoms. Those with cognitive dysfunction usually do not deal well with the intrinsic complexity of DBS therapy, and often have little overall functional gain even if motor performance is improved. When patients with PD that have dementia, it is often indicative of advanced disease process. Research has shown that those with advanced PD often are less responsive to DBS therapy. Secondly, the surgery is done awake and cognitive dysfunction may prevent one from tolerating and cooperating during surgery. In addition, there is a certain level of cognition and cooperation that is necessary for patients to partake in programming after surgery. Impaired cognition may inhibit patients from recognizing and verbalizing their symptoms and may cause difficulty participating in DBS programming or medication adjustments. Finally, if one has cognitive impairments pre-operatively, these may worsen after DBS surgery.In order to obtain a detailed understanding of each patient’s cognition and to further help in determine if one is a candidate for DBS, we may request that patients to obtain a formal neuropsychological evaluation.
- Clear evidence of motor improvement with Sinemet: How well a patient’s symptoms respond to dopaminergic medications, especially levadopa (Sinemet), often correlates to how well their symptoms will respond to DBS. When one has good motor function in the best on-medication state suggests they may respond well to DBS. Patients who fluctuate between good motor function while "on" and poor motor function while "off" are usually good surgical candidates.
In general, surgery makes the "off" states more like the "on" states (with medication) but rarely does better than the best (medicated) "on" state, therefore if you have poor function in the best "on" state (for example, non-ambulatory in best "on" state) you may be a poor surgical candidate.
- Lack of co-morbidities: Serious cardiac disease, uncontrolled hypertension, or any other major chronic systemic illness increases the risk and decreases the benefit of surgery. Pre-existing mood disorders including severe depression or anxiety can worse after DBS surgery and therefore, would not be advised.
- Realistic expectations: DBS surgery does not treat or cure the disease. DBS helps with some of the symptoms that PD causes. We encourage patients and family members to be realistic about what the outcome will be after surgery. It is also important to recognize what symptoms may be most bothersome and those symptoms that will likely not improve with DBS therapy. Those that expect complete resolution of symptoms or a miracle may be disappointed or frustrated with the complexity of DBS therapy.
- Patient age: Currently there is much debate on this topic. We do know that the benefits of DBS for PD decline with advanced disease process that often progresses with age. In addition, the risks associated with DBS surgery do increase with age. While age is considered, we do not have a specific age limit for DBS therapy. We take into account all the criteria that would make one a candidate and weigh this with the age of the patient. Patients over 75 are informed that their benefits are likely to be modest, mainly due to the advanced disease state. However, we have, in rare circumstances, implanted patients over the age of 80.
- Screening MRI of the brain: Before confirming one would be a candidate for DBS surgery, we would like to have an MRI of the Brain. This is to evaluate that the brain is free of severe vascular disease, atrophy that is out of proportion to age, or signs of atypical Parkinsonism.
- Degree of disability: The best time to surgically intervene is when the patient is just beginning to lose the ability to perform activities meaningful to him/her, in spite of optimal medical therapy. In a patient who is still working, the time to intervene is before the patient is forced to retire on disability.
While DBS may not be appropriate for early PD when the symptoms are very well controlled on medical therapy, DBS is a not appropriate to rescue someone with end stage PD.
It is important to note that speech dysfunction, difficulty swallowing, handwriting difficulties, instability of body, and freezing of gait are rarely responsive to DBS therapy. If these are your most debilitating symptoms with PD, you may not be an ideal candidate.
- Ability to remain calm and cooperative during awake brain surgery: A helpful "screening test" for how well one may tolerates surgery may be how well the patient tolerates an MRI scan. Surgery will last two to four hours for each side of the brain. Our nurses and operating room staff will be at your side talking to you throughout the entire surgery but overall we do need patients to remain calm and cooperative during the pre-operative MRI and surgery itself.
Coping with Parkinson's Disease
These free land and water classes are designed to benefit people with Parkinson’s by using exercise to help manage symptoms.
Emphasis is placed on exercises to improve balance, posture, flexibility, range of motion, coordination and gait. All levels of fitness ability are welcome.
Land: Tuesday, Thursday, 1-2 p.m.
Water: Friday, 1-2 p.m.
Please call 630-978-6280 for more information, the next class date or to register.
The Parkinson’s Support Group provides information about living with Parkinson’s disease. You’ll learn about resources and programs that can help enhance your quality of life and have the opportunity to share your experiences with others. Join us to be part of our comforting and understanding community.
- Rush-Copley Heart Institute
2088 Ogden Avenue, Aurora
First Wednesday of every month
10 to 11:30 a.m.
- Rush-Copley Healthcare Center
1100 W. Veterans Parkway, Yorkville
Third Wednesday of every month
1:30 to 3 p.m.