Deep Brain Stimulation (DBS) was pioneered in the 1990s by neurosurgeons Benabid, Pollak, and Gao, et al., as a means to provide relief from Parkinson's disease (PD) symptoms related to degeneration of body movements and tremor activity. A startling 92 percent of the surgical procedures performed showed fewer falls related to muscle rigidity and significantly less to obsolete tremor activity.
Identification
DBS is a surgical procedure used to initiate cognitive (thought processes) and motor-skill functioning in advanced cases of PD. The "Journal of the American Medical Association" (JAMA) suggests that this procedure is one of two surgical options available for advanced stages. The remaining option is ablation (a method of heating the tip of an electrode and inserting it into the target area, creating scar tissue (lesions) and cauterizing the overactivity and output signals responsible for tremors and rigidity of the muscles). DBS is the surgical placement of an implanted electrode which delivers a high-frequency stimulation to the affected areas without creating scar tissue. Similar to ablation however, this procedure helps to curb tremor activity and rigidity of the muscles which lead to difficulty walking, standing or carrying out daily activities without falling.
History
Deep brain stimulation as it is performed today began in the 1990s. JAMA mentions that the concept of stimulating certain affected brain areas via manipulation began in the 1950s with the thalamotomy (a process of cauterization in the thalmus region in the brain) and the pallidotomy (the same process only aimed at the globus pallidus internus region of the brain) to reduce tremor activity and with the hope of alleviating daily hassles related to muscle rigidity. This was prior to the scientific advancements made in drug therapy (i.e. levadopa for PD), now recommended for the first stages of PD (roughly the first five to 10 years). While it is not unusual to see thalamotomy and pallidotomy performed on patients with a predominant set of symptoms (either tremor or rigidity), deep brain stimulation has become a fairly common practice.
Significance
The latest news on DBS published by the "Journal of Neurology" suggests that the procedure used while the patient is in advanced stages of PD has shown significant improvements to decreasing susceptibility to falls. A group of neurologists in Toronto, Canada performed a two-part double-blind pilot study involving six PD patients who had considerable fall activity. This fall activity is due to gait (walking) and postural (standing) difficulty paired with the rigidity of muscles resulting from major dopamine (a brain chemical responsible for smooth muscle movements) loss or depletion. The pilot study produced findings linked to a reduction in fall activity and improved conditions for the six patients. Due to the positive response received with the use of DBS in this study, they are now considering DBS for Progressive Supranuclear Palsy (often misdiagnosed with PD).
What to Expect With Surgery
Surgery is performed by an experienced neurosurgeon. According to the Surgery Encyclopedia, the patient remains awake throughout the duration of the procedure and is provided a local anesthetic to numb the area. Using stereotactic magnetic resonance imaging (MRI) technology or a computed tomography scan prior to the procedure, the surgeon then makes a puncture hole in the skull that will be used for recording activity, to locate scar tissue, and to determine the exact location where the electrodes are to be placed for optimal benefit. The electrodes are inserted in either a single or double method.
Follow-Up Care and Potential Problems After Surgery
According to the Surgery Encyclopedia and the Annals of Neurology, there is a considerable potential for risks and complications following an invasive procedure in the brain. Being an implanted device (beneath the skin and deep into the brain) complications have involved cerebral hemorrhage (up to 10 percent), encephalitis (6 percent), malfunctioning of the device (9 to 17 percent), need for replacements (8 to 9 percent), headaches (25 percent) and seizure activity (3 percent). However, these risks are monitored for closely by the neurosurgeon and remedied rather quickly. Mortality rates involved with DBS are below 1 percent of the population which has undergone this procedure, deeming it predictably "safe" for use by the U.S. Food and Drug Administration.
References
- "Journal of Neurology: News on Treatment: From Antiepileptics in Childhood Absence Epilespy to Improvement of Falls in Parkinson's Disease by Deep Brain Stimulation;" Strupp, M; March 2010
- "The Journal of the American Medical Association [JAMA]: Surgical Treatment of Parkinson's Disease;" Eskandar, MD, E, Cosgrove, MD, FRCSC, R & Shinobu, MD, PhD, L A; December 2001
- Parkinson's Disease Foundation: Deep brain stimulation for Parkinson's disease
- Surgery Encyclopedia: Deep brain stimulation
- "Annals of Neuropsychology: No tissue damage by chronic deep brain stimulation in advanced PD
