When medication has ceased to be effective or the side effects from these drugs have become no longer tolerable, surgery might be an option your Doctor will consider and advise to help alleviate your symptoms and improve your quality of life. However not all sufferers of Parkinson’s will be a candidate for surgery, an example would be a person who didn’t respond very well to Levodopa treatment.
Of all the people suffering from this disease it is thought that only around 10% of them could be classed as possible suitable candidates for surgery. Another factor to consider when thinking of surgery is that while improvements could be gained there is also the risk factor to take into account that surgery of any kind has.
There is also the risk that the surgery might not make any improvements and could in fact make the symptoms worse. There are three main types of surgery which can be used in the treatment of Parkinson’s disease; these are ablative, stimulation, deep brain stimulation, transplantation and restorative surgeries.
Overview of Surgical Procedures
Some of the surgical procedures for Parkinson’s disease have been discussed below. Deep brain stimulation has been discussed in greater detail, however, this does not infer a preference for the procedure.
This type of surgery aims to locate, target and then destroy the defined area of the brain which is affected by the disease. The aim is get rid of all the tissue which produces the abnormal electrical or chemical impulses which in turn produce the symptoms of tremor in the patient.
This type of surgery is performed by inserting an electrode into the part of the brain affected by the disease; this method is often very difficult to guess correctly for if too much tissue is taken then it could lead to stroke or paralysis while if too little is taken the tremor might not be eliminated or could return.
The patient will remain awake during this procedure with a local anaesthetic being given to dull the feeling in the outer part of the brain. The brain itself cannot feel pain so it can be probed without any discomfort to the patient.
Transplantation or restorative surgery
This type of surgery relies on the implantation of dopamine producing cells being implanted directly into the striatum. Cells used for this process are taken from a variety of sources which include the patients own body, human embryos and pig embryos.
Deep brain stimulation
Deep brain stimulation is a surgical procedure which can help greatly with the symptoms most commonly associated with Parkinson’s disease such as rigidity, stiffness, slowed movement and problems with walking and movement. However deep brain stimulation at the present is only an option for those sufferers whose medication doesn’t adequately control their symptoms.
What’s involved with deep brain stimulation?
The surgery is performed by inserting a battery operated device which is called a neurostimulator, the stimulator then sends out pulses to targeted areas of the brain that control the patients movement. This in turn blocks the abnormal brain signals which cause the tremors commonly associated with Parkinson’s disease.
Before the surgery can be performed the neurosurgeon will perform an MRI scan to determine the area within the brain where nerve signals generate the symptoms of Parkinson’s. The areas which are generally targeted are the thalamus, subthalamic nucleus and the globus pallidus.
The entire system used for the stimulation consists of three major parts the lead or electrode, the extension and the neurotransmitter itself. A small opening in the skull is made and then the electrode is inserted and implanted into the brain, with the tip of the electrode positioned within the targeted area of the brain.
The extension is then passed just underneath the skin of the neck, head and shoulder and attached to the neurostimulator. The neurostimulator which is the source of energy or the battery pack is then located under the skin near to the collar bone, or in some cases in the chest.
Having made sure the entire system is in place electrical impulses are then sent from the neurostimulator along the extension and lead up to the brain. These impulses then block the signals that cause the symptoms of Parkinson’s disease.
What is the prognosis?
Many patients who have undergone the surgery do say that their symptoms are considerably reduced and while they can significantly reduce the amount of medication needed they still need to take it. The actual amount of reduction varies greatly from person to person but all have said it has been a considerable amount.
Currently research is continuing in deep brain stimulation to determine its reliability, safety and effectiveness as a treatment for Parkinson’s disease. Scientists are in particular studying the areas of the brain where the surgery would be most effective in the reducing symptoms.