Oregon’s contribution to tremor relief through Deep Brain Stimulation
By Shannon Anderson, MPAS, PA-C
The exam room was quiet. The patient sat apprehensively in the exam chair, a rest tremor shaking his limbs unrelentingly. It was only a few weeks following his brain surgery. Though I had walked my patient through each of the steps we would take during the visit, his nervousness persisted. I switched on the neurostimulator. At first, nothing. Carefully, gradually, I increased the voltage, and the tremor gradually slowed until finally disappearing completely. Calm. For the first time in years, this man stopped shaking.
Deep brain stimulation (DBS) is a procedure involving the delivery of high frequency stimulation to specific areas of the brain.
Most commonly it is used in the treatment of movement disorders such as Parkinson’s disease and Essential Tremor.
DBS for additional disorders such as obesity, dementia and depression is an active area of research.
The story of DBS begins in the 1980s in Grenoble, France with a neurosurgeon by the name of Alim-Louis Benabid. Prior to the procedure’s development, lesion surgeries were performed to alleviate disabling tremor. In order to locate the target, the neurosurgeon applied low frequency stimulation to the planned target as well as surrounding structures and observed the patient’s symptoms while the patient was awake. Dr. Benabid noticed that the patient’s tremor would often respond positively to this stimulation prior to the lesion even being made. He postulated that the application of stimulation may alleviate symptoms without requiring the destruction of tissue. DBS for movement disorders was born.
-Intraoperative image from a deep brain stimulation procedure, composed of the patient's pre-operative MRI fused with the intraoperative CT scan. Yellow and green lines demonstrate the planned trajectory, while the red dot denotes the planned target (in this case, the globus pallidus pars interna). The DBS electrode appears as a white hyperdensity beneath the target dot.
Equally important to the procedure is the management of the post-DBS patient. This involves programming the neurostimulator, which is analogous to finding the right dose. The DBS electrode is placed in a specific nucleus in the brain: for Parkinson’s disease this can be either the globus pallidus pars interna (GPi) or the subthalamic nucleus (STN).