White Matter Microstructural Similarity and Diversity of Functional Constipation and Constipation-predominant Irritable Bowel Syndrome

Abstract

Background/AimsThe Rome III criteria separated chronic constipation into functional constipation (FC) and constipation-predominant irritable bowel syndrome (IBS-C), but some researchers questioned the partitioning and treated both as distinct parts of a continuum. The study aims to explore the similarity and diversity of brain white matter between FC and IBS-C. MethodsThe voxel-wise analysis of the diffusion parameters was used to quantify the white matter changes of female brains in 18 FC patients and 20 IBS-C patients compared with a comparison group with 19 healthy controls by tract-based spatial statistics. The correlations between diffusive parameters and clinical symptoms were evaluated using a Pearson's correlation. ResultsIn comparison to healthy controls, FC patients showed a decrease of fractional anisotropy (FA) and an increase of radial diffusivity (RD) in multiple major fibers encompassing the corpus callosum (CC, P = 0.001 at peak), external capsule (P = 0.002 at peak), corona radiata (CR, P = 0.001 at peak), and superior longitudinal fasciculus (SLF, P = 0.002 at peak). In contrast, IBS-C patients showed FA and RD aberrations in the CC (P = 0.048 at peak). Moreover, the direct comparison between FC and IBS-C showed only RD differences in the CR and SLF. In addition, FA and RD in the CC were significantly associated with abdominal pain for all patients, whereas FA in CR (P = 0.016) and SLF (P = 0.040) were significantly associated with the length of time per attempt and incomplete evacuation separately for FC patients. ConclusionThese results may improve our understanding of the pathophysiological mechanisms underlying different types of constipation.

Patients With Chronic Migraine Without History of Medication Overuse Are Characterized by a Peculiar White Matter Fiber Bundle Profile

“…Of note, the presently observed neuroradiological ndings are similar to those found in relation to other types of cephalic and extra-cephalic chronic pain, such as trigeminal neuralgia [38], chronic musculoskeletal pain [39], irritable bowel syndrome [40]. This consistency further supports the hypothesis that WM ber bundles mediate pain perception and control, and that chronic pain of any type may account for the widespread disruption of WM integrity in the brain.…”

“…The headache severity was also related to the DTI metrics in the present study; the subjective perception of headache intensity was negatively correlated with FA and positively correlated with MD in the overlapping WM tracts of the right PCR in patients with CM and MO, respectively. Since the PCR forms part of the central pain modulatory circuit, and because a similar correlation was previously found in other chronic pain disorders [38,40], it is possible that an abnormal microstructural integrity of the PCR compromises the perception of pain severity. However, since this was not a longitudinal study, we cannot exclude the possibility that, conversely, the intensity of the pain itself caused the microstructural integrity anomalies.…”

Patients with chronic migraine without history of medication overuse are characterized by a peculiar white matter fiber bundle profile

“…Of note, the presently observed neuroradiological ndings are similar to those found in relation to other types of cephalic and extra-cephalic chronic pain, such as trigeminal neuralgia [38], bromyalgia [39], chronic musculoskeletal pain [40], and irritable bowel syndrome [41]. This consistency further supports the hypothesis that WM ber bundles mediate pain perception and control, and that chronic pain of any type may account for the widespread disruption of WM integrity in the brain.…”

Understanding Neurogastroenterology From Neuroimaging Perspective: A Comprehensive Review of Functional and Structural Brain Imaging in Functional Gastrointestinal Disorders

“…93 Comparing functional constipation, constipation-predominant IBS (IBS-C), and HC, the genu of the corpus callosum showed a negative association with abdominal pain or discomfort intensity in functional connectivity and IBS-C. On the other hand, functional connectivity exhibits more regions of WM changes than IBS-C, such as the corona radiate, which includes projection fibers associated with the corticopontine tract. 94…”