Neurostimulation

• Neurostimulation, or electrical therapy of the brain, is now commonly used to treat neurological disorders such as Parkinson’s Disease and Essential Tremor.  Recently, new inroads have been made in the use of neurostimulation devices for epilepsy.
• Medtronic has completed clinical trials using Deep Brain Stimulation (DBS) for patients with treatment resistant partial epilepsy.  Electrodes which deliver electrical impulses are implanted by a neurosurgeon in the anterior thalamus (a deep structure in the brain) on both sides of the brain.  Improvements in seizure control on average were modest for the duration of the study, but improved as subjects were followed over a longer period.  Approximately 10% developed infections related to the surgery, and a small number of subjects developed small bleeds around the electrodes which were not noticeable to the subject or treating physician.   A higher rate of depression, anxiety, and subjective memory difficulties was associated with active treatment, but these symptoms were usually transient.
• Neuropace, Inc. has completed clinical trials with its Responsive Neurostimulator (RNS)® device.  This device was tested in patients with treatment resistant partial epilepsy with one or two well-defined seizure generating regions (seizure foci) of the brain (this determination was made by the medical treatment team).  Electrodes were placed by a neurosurgeon over the seizure foci(s), which connected to a small computer implanted in the skull.  This computer was then trained by the medical team to recognize seizure activity and respond by delivering electrical impulses to attempt to stop the abnormal electrical activity of the seizure.  In the pivotal trial, seizure frequency reduction of 37.9 percent was seen in those receiving active therapy vs. 17.3 percent with sham therapy (the device was initially turned off).  Greater reductions of seizure frequency were seen over a longer period.
• At present, these devices are not available for clinical use and are under review by the Food and Drug Administration (FDA).  Although these methods hold promise, few are rendered seizure free, and most likely, these therapies will be used in combination with other treatments such as medical therapy.