This procedure locates, targets, and then destroys (ablates) a clearly-defined area of the brain affected by Parkinson's disease. The goal of this surgery is to destroy tissue that produces abnormal chemical or electrical impulses that result in tremors and dyskinesias.
In ablative surgery, a heated probe or electrode is inserted into the targeted area. During the procedure, it may be difficult to determine how much tissue to destroy and the amount of heat to use. It is safer to treat a small area and risk the tremor returning or not being eliminated, than to treat a larger region and risk serious complications, such as paralysis or stroke.
Types of ablative surgery include pallidotomy or thalamotomy. Pallidotomy—ablation in the part of the brain called the globus pallidus—involves putting a hole (i.e., otomy) in the globe-shaped structure located deep inside the brain. This procedure is performed to eliminate uncontrolled dyskinesias. Thalamotomy—ablation of brain tissue in the thalamus—involves creating an otomy in the structure located below the globus pallidus. The procedure is performed to eliminate tremors. A related procedure, called cryothalamotomy, uses a supercooled probe that is inserted into the thalamus to freeze and...
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