Parkinson Disease: Ready… Aim… Implant!
Many long-time sufferers of Parkinson disease are finally getting the help they need with the implantation of a Deep Brain Stimulator. During implantation, neurosurgeons aim for an exact location in the brain, but two questions remained, How close to this ideal spot are they really getting? and How much does it matter? Dr. Guy McKhann from our Center for Movement Disorders was among researchers* who set out to answer these questions in a retrospective study published in the Journal of Clinical Neuroscience.
Parkinson disease is a chronic degenerative disease of the brain that causes the body to “freeze up,” making limbs stiff and movement slow. People with Parkinson disease often have a tremor when they are resting, and initiating purposeful movement (like walking) takes a bit longer than usual. You can’t rush someone with this condition, nor should you, because the disease often affects balance and increases the risk of falling.
In the 1960s the drug L-Dopa was introduced and radically changed the lives of many Parkinson disease sufferers by almost eliminating their symptoms. Unfortunately, this drug doesn’t help everyone all the time. Sometimes after years of working well, with progression of the disease, the drug no longer helps. For these patients, the authors say that implanting a deep brain stimulator in a part of the brain called the subthalamic nucleus, can be the most beneficial surgical intervention.
With deep brain stimulation (DBS) surgery, a small electrode is placed in the critical parts of the brain that help to control movement. The electrode is attached to a small battery in the chest wall and is connected by wires that are placed under the skin. The stimulator is then turned on and interrupts the normal flow of information in the brain and can help to decrease symptoms of Parkinson disease. —Columbia Neurosurgery page on Parkinson disease
The subthalamic nucleus is tiny, and implanting an electrode in the part of it that controls movement can be tricky, and it takes a lot of preparation. The area is targeted using sophisticated imaging techniques, then surgeons pick the safest part of the brain to enter, and with incredible precision, they aim right at the spot they want. This way, they can go straight in without disrupting any more of the brain than they have to.
The authors* of this study wanted to look at patients who had already had this surgery and see how close to the target their surgeons had gotten. They also wanted to see if the distance away had any effect on the outcome. In particular they looked at whether it affected movement in the legs.
The authors found that surgeons were consistently within two millimeters of their target, and the distances from the target were not related to how the patient fared. In other words, even when they didn’t hit the target exactly, the patient wasn’t the worse for it.
To learn more see the authors’ paper, Typical Variations of Subthalamic Electrode Location do not Predict Limb Motor Function Improvement in Parkinson’s Disease in the Journal of Clinical Neuroscience.
*List of the research paper’s authors: Shearwood McClelland III, Blair Ford, Patrick B. Senatus, Steven J. Frucht, Linda M. Winfield, Qiping Yu, Yunling E. Dud, Seth L. Pullman, Guy M. McKhann II, Robert R. Goodman
Originally published on Jan 14, 2010
Updated on April 14, 2017
In Blog, Brain Tumor Blog, Epilepsy Blog, Gamma Knife Blog, Movement Disorders Blog Tags: , brain stimulator, DBS, Deep Brain Stimulator, Dr. McKhann, Subthalamic Nucleus