Objective: To investigate the brain functional connectivity (FC) changes of the periaqueductal gray (PAG) in right classical trigeminal neuralgia (CTN) patients using resting state functional MRI (rs-fMRI). Methods: rs-fMRI data were acquired in 21 right CTN patients and 35 healthy controls (HC).PAG was selected as region of interest (ROI).The linear correlation between PAG and whole brain was calculated and the FC changes were compared between groups.Furthermore,correlation analysis was performed to study whether illness duration and/or pain ratings were related to the abnormal FCs in right CTN group. Results: Compared with the controls,PAG in right CTN group showed a significantly increased FC with bilateral anterior cingulate cortex (ACC) and right supramarginal gyrus (GRF correction for multiple comparisons, P <0.01).Besides,the FC between PAG and bilateral ACC was positively related to the illness duration ( P =0.007),pain sensory rating ( P = 0.005) and pain affective rating ( P =0.006) in right CTN group. Conclusion: This study provides imaging evidence of brain functional integration impairments in right CTN patients,which may contribute to further understanding of the possible central neural mechanisms of CTN.
Magnetic resonance imaging