Pallidotomy (posteroventral pallidotomy) for Parkinson's disease
Surgery Overview
In Parkinson's disease, a part of the brain called the globus pallidus is overactive, which causes a decrease in the activity of a different part of the brain that controls movement.
In a pallidotomy, the surgeon destroys a tiny part of the globus pallidus by creating a scar. This reduces the brain activity in that area, which may help relieve movement symptoms such as tremor and stiffness (rigidity).
Before surgery, detailed brain scans using MRI are done to identify the precise location for treatment.
The person is awake during the surgery, but the scalp area where instruments are inserted is numbed with a local anesthetic. The surgeon inserts a hollow probe through a small hole drilled in the skull to the target location. An extremely cold substance, liquid nitrogen, is circulated inside the probe. The cold probe destroys the targeted brain tissue. The probe is then removed, and the wound is closed.
Surgery on one side of the brain affects the opposite side of the body. If you have tremor in your right hand, for instance, the left side of your brain will be treated. The procedure can be repeated on the other side of the brain if needed.
What To Expect After Surgery
The surgery usually requires a 2-day hospital stay. Most people recover completely within about 6 weeks.
Why It Is Done
Pallidotomy may be considered when a person with advanced Parkinson's disease has:
- Developed severe motor fluctuations, such as dyskinesias and on-off responses, as a result of long-term levodopa treatment.
- Severe or disabling tremor, stiffness (rigidity), or slow movement (bradykinesia) that medication can no longer control.
Pallidotomy probably is not a good choice for treatment when a person has not responded to levodopa. Some studies suggest that people with parkinsonian symptoms who do not improve with levodopa therapy do not gain much benefit from pallidotomy.
How Well It Works
The most striking effect of pallidotomy is a reduction in the involuntary movements (dyskinesias) that are caused by long-term levodopa therapy. This improvement can be seen almost immediately. By reducing these side effects, pallidotomy enables some people to adjust their levodopa dosage, which allows for better symptom control.
Pallidotomy may reduce tremor, muscle rigidity, slow movement, and other motor symptoms. Balance and speech may be improved.
It is not known how long the effects of pallidotomy can be expected to last. Benefits may fade over time in some people.
Doctors rarely perform pallidotomy anymore. Instead, doctors use deep brain stimulation, a procedure that does not destroy brain tissue and has fewer risks than pallidotomy.
Risks
This type of brain surgery has less risk today than in the past because technology allows the surgeon to identify with great precision the area of the brain that will be treated. Serious permanent complications are not common, although less serious side effects are.1
Complications of pallidotomy can include a stroke caused by bleeding in the brain, which may result in:
- Partial loss of vision on one side.
- Temporary facial paralysis.
- Weakness, loss of sensation, or loss of voluntary movement (paralysis) on one side of the body.
- Loss of speech, or slurred speech and difficulty swallowing. (This is more common when pallidotomy is done on both sides of the brain.)
- Temporary balance problems.
- Numbness around the mouth (leading to drooling) and in the hands.
- Death in some cases.
Many people who have a stroke recover fully and benefit from pallidotomy. Pallidotomy has caused problems with thought and memory (cognitive impairment) in some people.
Other risks include:
- Infection.
- Seizures.
What To Think About
The effectiveness, lower risk, and nondestructive nature of deep brain stimulation have made it the preferred option for most people who are considering surgery to treat advanced Parkinson's disease. However, pallidotomy may be considered in some cases when medication has failed to control symptoms adequately and deep brain stimulation is not appropriate. Like deep brain stimulation, pallidotomy neither cures Parkinson's disease nor eliminates the need for medication. After surgery, treatment with levodopa and other medications will be continued and the doses adjusted as needed.
Complete the surgery information form (PDF)
(What is a PDF document?) to help you prepare for this surgery.
| Author: | Douglas Dana Monica Rhodes | Last Updated: February 12, 2007 |
| Medical Review: | Anne C. Poinier, MD - Internal Medicine E. Gregory Thompson, MD - Internal Medicine Colin Chalk, MD, CM, FRCPC - Neurology | |
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| Topic Contents | |
| Surgery Overview | |
| What To Expect After Surgery | |
| Why It Is Done | |
| How Well It Works | |
| Risks | |
| What To Think About | |
| References | |