ABSTRACT
Functional neurosurgery treats neurological disorders by changing the activity of neural circuitry. Deep brain stimulation (DBS) is a form of electrical neuromodulation that involves chronic implantation of an electrode within various sites of the human brain. By 2006, more than 40,000 stimulators were implanted worldwide (Benabid et al., 2006). The most common indication is the treatment of symptoms of movement disorders, but conditions such as depression, obsessive-compulsive disorder and chronic neuropathic pain are other frequent targets. The last of these, chronic pain, is a huge burden to society and to those individuals affected. It results from a wide variety of conditions, such as trauma, cancer, stroke and failed surgery (Ashburn and Staats, 1999), with a suspected prevalence of over 20% (Gureje et al., 1998). DBS for chronic pain has been shown to in¬uence not only pain pathways, but also the autonomic nervous system with which it is intimately associated. In this chapter, we describe the application of heart rate variability (HRV) in the intra-operative and post-operative assessments of functional neurosurgery procedures, in particular, DBS for chronic neuropathic pain, and novel applications of DBS.
