White matter changes in young and middle-aged males with chronic prostatitis/chronic pelvic pain syndrome: Tract-based spatial statistics analysis.

The supraspinal mechanism plays a key role in developing and maintaining chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS). However, it is not clear how white matter changes in young and middle-aged males with CP/CPPS. In this cross-sectional study, 23 CP/CPPS patients and 22 healthy controls (HCs) were recruited. Tract-based spatial statistics was applied to investigate the differences in diffusion tensor imaging metrics, including fractional anisotropy (FA), mean diffusion (MD), radial diffusion (RD) and axial diffusion (AD), between CP/CPPS patients and HCs. The study also examined the association between white matter alterations and clinical variables in patients using correlation analysis. Compared with HCs, patients showed decreased FA, MD, RD and AD in the body and genu of the corpus callosum and right anterior corona radiata. In addition, they showed increased FA along with decreased MD, RD and AD in the left posterior limb of the internal capsule (PLIC-L), left external capsule and left cerebral peduncle. The FA of PLIC-L was negatively correlated with disease duration (r = -.54, corrected p = .017), while MD and RD were positively correlated (r = .45, corrected p = .042; r = .57, corrected p = .017). These results suggest that CP/CPPS is associated with extensive changes in white matter tracts, which are involved in pain processing. In particular, the FA, MD and RD values in the PLIC-L were correlated with the disease duration, indicating that the long-term course of CP/CPPS may have effects on the white matter microstructure of the pain perception pathways.

The functional connectivity of the basal ganglia subregions changed in mid-aged and young males with chronic prostatitis/chronic pelvic pain syndrome.

Background: The Basal ganglia (BG) played a crucial role in the brain-level mechanisms of chronic pain disorders. However, the functional changes of BG in chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) are still poorly understood. This study investigated the BG subregions' resting-state functional connectivity (rs-FC) in CP/CPPS patients compared with healthy controls. Methods: Twenty eight patients with CP/CPPS and 28 age- and education-matched healthy males underwent clinical measurements and 3T brain MR imaging, including T1-weighted structural images and resting-state functional imaging. The data were analyzed by the seeded-based rs-FC analysis. Then, a machine learning method was applied to assess the feasibility of detecting CP/CPPS patients through the changed rs-FC. Results: Compared with healthy males, patients presented decreased rs-FC between the BG subregions and right middle cingulate cortex, and correlated with pain (r = 0.51, p-uncorrected = 0.005) and urinary symptoms (r = -0.4, p-uncorrected = 0.034). The left superior temporal gyrus and right supramarginal gyrus showed decreased rs-FC with the BG subregions as well. The area under the receiver operating characteristic curve of 0.943 (accuracy = 80%, F1-score = 80.6%) was achieved for the classification of CP/CPPS patients and healthy males with support vector machine (SVM) based on the changed rs-FC. Conclusion: These findings provide evidence of altered BG subregions' rs-FC in CP/CPPS, which may contribute to our understanding of the BG's role in CP/CPPS.

The relationship between putamen-SMA functional connectivity and sensorimotor abnormality in ESRD patients.

The basal ganglia (BG) are composed of several nuclei involved in neural processing associated with integration of sensory and motor information. Recent neuroimaging studies implicated its key role in control of voluntary motor function. As the sensorimotor abnormality is common among the end-stage renal disease (ESRD) population, in the current study, we aimed to investigate the abnormal structure and functional connectivity patterns of BG in ESRD patients. Twenty-nine ESRD and twenty-nine age and gender-matched healthy controls (HC) were enrolled to compare the volume of the subsets in the BG (e.g., caudate nucleus, putamen and globus pallidus) by using the VBM analysis; resting-state functional connectivity was analyzed by a seed-based method. Compared with the HC group, ESRD patients had a smaller volume in the right putamen. Taking the right putamen as a seed region, we further found reduced functional connectivity in patients mainly between the putamen and supplementary motor area (SMA), insula, posterior mid-cingulate gyrus, and primary motor cortex. In ESRD group, the severity score of restless legs syndrome was negatively correlated with putamen-SMA functional connectivity, while the hemoglobin level was positively correlated with functional connectivity degree between the putamen and SMA. Our results revealed an abnormal volume of the putamen and its decreased functional connectivity patterns during resting state in ESRD with sensorimotor abnormalities. These preliminary results indicated that the decreased functional connectivity in putamen-SMA was associated with sensorimotor abnormalities, and anemia was correlated with this abnormal functional pattern in ESRD patients.

Abnormal structure and functional connectivity of the anterior insula at pain-free periovulation is associated with perceived pain during menstruation.

Neuroimaging studies have demonstrated the critical role of the insula in pain pathways and its close relation with the perceived intensity of nociceptive stimuli. We aimed to identify the structural and functional characteristics of the insula during periovulatory phase in women with primary dysmenorrhea (PDM), and further investigate its association with the intensity of perceived pain during menstruation. Optimized voxel-based morphometry and functional connectivity (FC) analyses were applied by using 3-dimensional T1-weighted and resting functional magnetic resonance imaging (fMRI) in 36 patients at the peri-ovulation phase and 29 age-, education-, and gender-matched healthy controls (HC). A visual analogue scale (VAS) was used to examine the intensity of the abdominal pain at periovulation and menstruation. In our results, PDM patients had significant higher VAS-rating during menstruaion than periovulation. Compared with the HC, PDM patients had lower gray matter density in the left anterior insula (aINS). Taken the left aINS as a seed region, we further found hypoconnectivity between aINS and medial prefrontal cortex (mPFC), which showed negative relation with the VAS during menstruation. As the aINS is a key site of the salience network (SN) and the mPFC is a critical region in the default mode network (DMN), it's implicated a trait-related central-alteration that communications between pain attention and perception networks were disrupted without the ongoing menstrual pain. Moreover, result of correlation analysis, at least in part, suggested a possible role of altered FC (pain-free period) in predicting pain perception (menstruation).