Dorsal Root Ganglion Stimulation: A Target for Neuromodulation Therapies

Abstract

As the cellular basis of the sensory nervous system was being mapped, the anatomy and physiology of the primary sensory neurons was quickly recognized to be important. The dorsal root ganglion (DRG) is more than a common pathway by which sensory information is transmitted from the periphery proximally to spinal and supraspinal regions. Research in the past 10 years has demonstrated the importance of the primary sensory neurons housed in the DRG with regard to the development and maintenance of chronic pain conditions. Alterations in the neurophysiology of these cells are manifested in several ways, and many of these alterations are specific to the cell soma in the DRG and not to other regions along the path of the pseudounipolar projections. Since the DRG is a potentially important target for treatment, various techniques such as local pharmacologic injections and delivery of radiofrequency energy have been utilized. These techniques provide relatively short-term pain relief. A new method for stimulating the DRG has been developed, the goal of which is to produce long-term neuromodulation of cells in the ganglion to treat chronic pain conditions. This technique uses specialized equipment and low-energy output to produce therapeutic result. Specific potential advantages to this approach are discussed.