Insular hypometabolism in a patient with fibromyalgia: a case study.

BACKGROUND: Neuroimaging studies have demonstrated differential involvement of a variety of brain centers in fibromyalgia both at baseline and in response to stimulation. The insular cortex is one such structure. FINDINGS: A 46-year-old woman with chronic widespread pain underwent positron emission tomography utilizing 18F-fluorodeoxyglucose while participating as a healthy control subject in a brain imaging study. Analysis of the scan revealed metabolic hypoactivity within the left insular cortex as an incidental finding. Soon after her scan, she underwent further clinical evaluation and was subsequently diagnosed with fibromyalgia. DISCUSSION: The potential contribution of insular dysfunction to the development of hyperalgesia has been demonstrated in rat models via local manipulations of dopaminergic, gamma-aminobutyric acid (GABA) ergic, and opioidergic neurotransmission within this region. Thus, our demonstration of insular hypometabolism in this patient's case may have bearing on her experience of chronic widespread pain.