Functional and anatomical connectivity in Complex Regional Pain Syndrome: A Multi-modal magnetic resonance imaging study

Abstract

Pain processing relies on a distributed network of cortical regions. It is therefore proposed that cortical connectivity analyses may be useful for examining the abnormal cortical network interactions that modulate pain perception, and other symptoms, in chronic pain conditions. The present study used functional magnetic resonance imaging and diffusion weighted magnetic resonance imaging to investigate differences in functional and anatomical connectivity between healthy controls and patients with complex regional pain syndrome (type 1). It was hypothesised that this chronic pain condition would associate with changes in functional connectivity within resting-state networks, as well as changes in fractional anisotropy in white matter tracts. Results suggested that there is increased functional connectivity between regions of the sensorimotor resting-state network, and that there is decreased fractional anisotropy in the portion of the superior longitudinal fasciculus connecting these regions. These regions correspond to primary and secondary somatosensory cortices, which have been implicated in the sensory-discriminative aspect of pain processing. This supports the hypothesis that there are both functional and anatomical changes within pain processing networks, in patients with complex regional pain syndrome.