Until the discovery of levodopa in the 1960s, surgery was one of the few treatments available to treat people with Parkinson’s disease. Once levodopa became an established therapy, the use of surgery was largely discontinued, except to help people who had drug-resistant symptoms.
Nowadays, medication is the main treatment for Parkinson’s disease. Various types are available – see the section on Medication. These offer effective symptom control for many people, but are not perfect treatments, especially for people who are in the more advanced stages of Parkinson’s. For this reason, and because there have been many advances in surgical techniques, neuroimaging and computer technology that make surgery more viable, in recent years there has been a revival of interest in surgery.
Surgery is mainly used to treat people with advanced Parkinson’s who are finding that medication does not offer the same level of symptom relief as it used to do and those who have drug-resistant symptoms. Surgery does have some risks and some people will not be suitable for this type of treatment, particularly anyone with psychiatric problems, dementia, cerebrovascular disease, uncontrolled high blood pressure or who is 75 years or more.
Although some surgical techniques have provided good symptom control in some people, it is important to remember surgery is not a cure and it does not slow down the progression of Parkinson’s. Most people continue to take Parkinson’s medication after surgery although sometimes the dose they take can be reduced.
What types of surgery are of interest to researchers?
There are several surgical techniques currently being researched. These include:
This section has been adapted, with kind permission of the author, from the chapter on surgery contained inLiving with Parkinson’s diseaseby Bridget McCall. Published by Sheldon Press (London, UK) 2006.
The progressive deterioration in intellectual and cognitive abilities including impairment of memory, inability to pay attention and learn, make decisions and solve problems. This typically has an adverse effect on emotions, and learning capabilities and may affect language, personality and abstract reasoning and judgement.
Dementia is not a disease in itself, but a generic term given to a group of symptoms that characterize other diseases and conditions.
The main type of drug prescribed to treat Parkinson's disease and has been in use since the late 1960s. The aim is to increase the levels of dopamine in the brain. Dopamine cannot be directly replaced because it cannot cross the blood-brain barrier that prevents potentially harmful substances in the blood from entering the brain. Levodopa is a chemical compound that can cross this barrier and is then converted into dopamine.
See also Types of medication available.
Medical imaging techniques that enable doctors to study structures and functioning within the brain and nervous system.
Pallidotomy is a surgical operation where a tiny electrical probe is placed in the globus pallidus internus (GPi), one of the basal ganglia of the brain involved with the control of movement, in order to destroy a small area of brain cells. This reduces the brain activity in that area, which may help relieve motor symptoms such as tremor and stiffness (rigidity ).
Before surgery, detailed brain scans using MRI are carried out to identify the precise location for treatment. The probe heats surrounding tissue by emission of radio waves and the heat destroys nearby tissue.
Until the late 1990s, pallidotomy was the most common type of Parkinson's disease surgery. Doctors now rarely perform pallidotomy due to risks involved. Instead, doctors use deep brain stimulation, a procedure that does not destroy brain tissue and has fewer risks than pallidotomy.
A surgical operation in which a specific groups of cells within the thalamus that controls some involuntary movements is surgically destroyed.
Before surgery, detailed brain scans using a CT scan or MRI are done to identify the precise location for treatment. This procedure is often poorly tolerated because of increased complication and risk, including vision and speech problems. The positive effects on tremor are immediate. Other less destructive procedures are preferred, such as subthalamic deep brain stimulation (DBS), since this procedure can also improve tremor and other symptoms of Parkinson's disease.
