Functional Imaging of Central Nervous System Involvement in Complex Regional Pain Syndrome

A, Contrast map of the general linear model (GLM) calculated by subtracting the tapping condition of controls (right hand) from the tapping condition in patients (CRPS-affected side [ie, right hand]). Brain sections are referred to by the superior-inferior level in millimeters relative to a line through the anterior and posterior commissure. Z-score indicates level of significance. B, Contrast map of the GLM calculated by subtracting the tapping condition on the unaffected side (ie, left hand) from the affected side (ie, right hand) in patients with CRPS. Brain sections are referred to by the superior-inferior level in millimeters relative to a line through the anterior and posterior commissure. Z-score indicates level of significance. C, Implementation of the individual degrees of motor impairment (z-values of tapping frequencies [ie, values of the individual maximum tapping frequencies normalized to the mean maximum tapping frequencies of controls]) as regressors in the GLM model for the condition “tapping on the CRPS-affected side.” With this approach, brain areas correlating with the degree of motor impairment are isolated. Key areas of activations are indicated according to the following abbreviations: SFC indicates superior frontal cortex; MFC, middle frontal cortex; IFC, inferior frontal cortex; AIP, anterior intraparietal area, MIP, medial intraparietal area; mtc, middle temporal cortex; loc, lateral occipital complex. Reprinted with permission of Oxford University Press from Maihöfner et al.⁴⁸