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based on electrode location using MRI and CT images. Short duration pulses are normally employed to reduce charge injection and increase the therapeutic window with non-damaging stimulation. Some examples of stimulus parameters include frequencies of 0-15 HZ, pulse widths of 60-450 microseconds and voltages up to 10.5 volts. Some short-term adverse effects of DBS are paresthesias, headache, dysarthria, paresis, gait disturbances and ataxia. These adverse effects can usually be managed by adjusting the stimulation parameters.

Therapeutic Brain Stimulation

Reconstruction of DBS electrodes implanted in the substantia nigra and subthalamic necleus.

Parkinson’s disease (PD). Medtronic was one of the first manufactures to develop neural stimulators for French neurosurgeons to treat movement disorders in 1987. Canada, Europe and Australia approved the use of Medtronic’s IPG for movement disorders in 1993. The United States Food and Drug Administration approved DBS of thalamic nuclei for

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Sierra Sacramento Valley Medicine

PD-related tremors in 1997, followed in 2003 for the subthalamic nucleus (STN) and globus pallidus (GP). PD is a neurodegenerative disease characterized by symptoms of rigidity, tremor, bradykinesia and postural instability. DBS is only recommended for patients with medically-refractory PD who demonstrate no symptoms of cognitive impairment. The STN is currently the optimal stimulation target for reducing the occurrence of movement disorders. The patient is still required, in most instances, to maintain a schedule of medications at a reduced dosage. Most patients with PD who have undergone DBS experience an improved quality of life with a reduction of dyskinesias. Tourette’s Syndrome (TS). Tourette’s, which is characterized by multiple motor tics, is observed more frequently in pediatric populations and generally disappears by adulthood. DBS is not recommended as a functional neurosurgical treatment for children, and consequently is reserved only for intractable TS adult patients. There are multiple effective DBS target sites in the thalamus, including the centromedian (CM) as well as the globus pallidus (GP). TS patients receiving DBS have a 37-82 percent favorable response rate with sustained tic reduction for up to 10 years following surgery. Obsessive Compulsive Disorder (OCD). OCD is characterized by timeconsuming intrusive thoughts (obsessions) and compulsions that interfere with the individual’s level of social and occupational functioning. OCD affects approximately 1-2 percent of the population with 40 percent of those responding unfavorably to

2015-Sep/Oct - SSV Medicine  

Sierra Sacramento Valley Medicine is the official journal of the Sierra Sacramento Valley Medical Society (SSVMS) and promotes the history,...

2015-Sep/Oct - SSV Medicine  

Sierra Sacramento Valley Medicine is the official journal of the Sierra Sacramento Valley Medical Society (SSVMS) and promotes the history,...