Neurochemical Imaging as a Probe of Chronic Pain and Its Treatment

PAINWeek Podcasts

Accumulating evidence suggests that widespread pain syndromes such as fibromyalgia display a generalized disturbance in central nervous system pain processing. Multiple lines of research have identified that the locus for many functional chronic pain disorders, including fibromyalgia, pelvic pain, and irritable bowel syndrome, is within the central nervous system, and the brain more specifically. Brain neuroimaging techniques have heralded a revolution in our understanding of chronic pain, as they have allowed researchers to noninvasively evaluate brain structure and function. In addition, growing interest has turned to proton magnetic resonance spectroscopy (1H-MRS), a noninvasive magnetic resonance imaging technique that can quantify the concentration of glutamate and GABA, the brain's main excitatory and inhibitory neurotransmitters, respectively, within the living human brain. During this presentation, we will explore the ability and utility of 1H-MRS to identify brain neurotransmitter concentrations in chronic pain patients. Moreover, we will examine how 1H-MRS may provide insight into the mechanism(s) of action of pharmacologic as well as nonpharmacologic therapies. A key question: Are alterations in neurotransmitter levels along the causal pathway for the development/ maintenance of chronic pain, or are they simply a response to sustained peripheral input?