Use of functional magnetic resonance imaging in patients with irritable bowel syndrome and functional dyspepsia

Functional dyspepsia assessment - current diagnostic methods and new promising techniques

Functional Dyspepsia (FD) is a disorder of gut-brain interaction (DGBI) characterized by chronic symptoms without an organic cause. Diagnosis follows the Rome IV criteria, requiring symptoms for at least six months. FD affects up to 20% of the population, significantly impacting the quality of life and healthcare systems. Upper gastrointestinal endoscopy is often performed to rule out organic disorders but has limited utility in typical FD cases. FD's etiology involves gastric motility alterations, dysbiosis, and immune and central nervous system dysfunction. This review summarizes FD diagnostic methods. A PubMed search was conducted using keywords: Functional Dyspepsia, Gastric Motility Assessment, ROME IV, and Gastric Emptying (GE). Relevant studies were manually reviewed, excluding those unrelated to FD or gastric motility assessment. Despite extensive research on organic gastrointestinal diseases, FD's pathophysiology remains unclear, necessitating further studies. Diagnostic methods include the rapid water and nutrient drink tests for assessing impaired gastric accommodation, hypersensitivity, and delayed gastric emptying. Drinking-ultrasonography and three-dimensional ultrasound evaluate gastric motor and sensory functions. MRI-based assessments provide detailed stomach volume and geometry insights. Gastric emptying scintigraphy and the 13C-gastric emptying breath test measure gastric emptying rates. High-resolution electrogastrography (HR-EGG) assesses gastric myoelectrical activity, while EndoFLIP measures sphincter function. Functional MRI and PET scans analyze brain activity related to FD symptoms.  These methodologies enhance the understanding and management of FD by providing objective measures of gastric motility, accommodation, and sensory function. The integration of these advanced techniques into clinical practice holds the potential to move beyond symptom-based diagnosis, allowing for a more precise, individualized approach to treatment. Standardizing these diagnostic modalities will be crucial in optimizing patient care and alleviating the burden of FD on healthcare systems.

Clinical diagnosis, prevention, and treatment of neurodyspepsia syndrome using intelligent medicine

Against the backdrop of rapid social economy and scientific and technological development, intelligent medical technology expanded based on the Internet plays a crucial role in the innovation and development of the modern medical industry. Intelligent medical technology has completely changed the fixed medical methods of the past, and it can solve the isolated defects between various unit systems, greatly improving the overall informatization level of hospitals. This article analyzed the clinical diagnosis, prevention, and treatment of neurodyspepsia syndrome (NDS) in intelligent medicine. Dyspepsia can cause palpitations, vomiting, abdominal distension, dizziness, and other symptoms so that it can cause discomfort and pain in the middle or around the epigastric region. Therefore, it is necessary to make a correct diagnosis of neurodyspepsia in order to reduce the discomfort of patients. Intelligent medical technology is of great significance in improving patients' symptoms. This study sets up a control group and an experimental group for the experiment. The control group used conventional medication technology, while the experimental group used intelligent medical technology to analyze the patient samples taken. By comparing the factors that affect patients with NDS, it was found that the physical function score of the experimental group was 6.3% lower than that of the control group. Intelligent medical technology has high diagnostic efficiency and can achieve rapid diagnosis of NDS, meeting the clinical diagnosis and prevention requirements of NDS.

Central Regulation of Eating Behaviors in Humans: Evidence from Functional Neuroimaging Studies

Neuroimaging has great potential to provide insight into the neural response to food stimuli. Remarkable advances have been made in understanding the neural activity underlying food perception, not only in normal eating but also in obesity, eating disorders, and disorders of gut-brain interaction in recent decades. In addition to the abnormal brain function in patients with eating disorders compared to healthy controls, new therapies, such as neurofeedback and neurostimulation techniques, have been developed that target the malfunctioning brain regions in patients with eating disorders based on the results of neuroimaging studies. In this review, we present an overview of early and more recent research on the central processing and regulation of eating behavior in healthy and patient populations. In order to better understand the relationship between the gut and the brain as well as the neural mechanisms underlying abnormal ingestive behaviors, we also provide suggestions for future directions to enhance our current methods used in food-related neuroimaging studies.

Aberrant resting-state functional connectivity and topological properties of the subcortical network in functional dyspepsia patients

Functional dyspepsia (FD) is a disorder of gut-brain interaction. Previous studies have demonstrated a wide range of abnormalities in functional brain activity and connectivity patterns in FD. However, the connectivity pattern of the subcortical network (SCN), which is a hub of visceral information transmission and processing, remains unclear in FD patients. The study compared the resting-state functional connectivity (rsFC) and the global and nodal topological properties of SCN between 109 FD patients and 98 healthy controls, and then explored the correlations between the connectivity metrics and clinical symptoms in FD patients. The results demonstrated that FD patients manifested the increased rsFC in seventeen edges among the SCN, decreased small-worldness and local efficiency in SCN, as well as increased nodal efficiency and nodal degree centrality in the anterior thalamus than healthy controls (p < 0.05, false discovery rate corrected). Moreover, the rsFC of the right anterior thalamus-left nucleus accumbens edge was significantly correlated with the NDSI scores (r = 0.255, p = 0.008, uncorrected) and NDLQI scores (r = −0.241, p = 0.013, uncorrected), the nodal efficiency of right anterior thalamus was significantly correlated with NDLQI scores (r = 0.204, p = 0.036, uncorrected) in FD patients. This study indicated the abnormal rsFC pattern, as well as global and nodal topological properties of the SCN, especially the bilateral anterior thalamus in FD patients, which enhanced our understanding of the central pathophysiology of FD and will lay the foundation for the objective diagnosis of FD and the development of new therapies.

Psychological stress in inflammatory bowel disease: Psychoneuroimmunological insights into bidirectional gut–brain communications

Inflammatory bowel disease (IBD), mainly including ulcerative colitis (UC) and Crohn’s disease (CD), is an autoimmune gastrointestinal disease characterized by chronic inflammation and frequent recurrence. Accumulating evidence has confirmed that chronic psychological stress is considered to trigger IBD deterioration and relapse. Moreover, studies have demonstrated that patients with IBD have a higher risk of developing symptoms of anxiety and depression than healthy individuals. However, the underlying mechanism of the link between psychological stress and IBD remains poorly understood. This review used a psychoneuroimmunology perspective to assess possible neuro-visceral integration, immune modulation, and crucial intestinal microbiome changes in IBD. Furthermore, the bidirectionality of the brain–gut axis was emphasized in the context, indicating that IBD pathophysiology increases the inflammatory response in the central nervous system and further contributes to anxiety- and depression-like behavioral comorbidities. This information will help accurately characterize the link between psychological stress and IBD disease activity. Additionally, the clinical application of functional brain imaging, microbiota-targeted treatment, psychotherapy and antidepressants should be considered during the treatment and diagnosis of IBD with behavioral comorbidities. This review elucidates the significance of more high-quality research combined with large clinical sample sizes and multiple diagnostic methods and psychotherapy, which may help to achieve personalized therapeutic strategies for IBD patients based on stress relief.

Cine gastric MRI reveals altered Gut-Brain Axis in Functional Dyspepsia: gastric motility is linked with brainstem-cortical fMRI connectivity

BACKGROUND

Functional dyspepsia (FD) is a disorder of gut-brain interaction, and its putative pathophysiology involves dysregulation of gastric motility and central processing of gastric afference. The vagus nerve modulates gastric peristalsis and carries afferent sensory information to brainstem nuclei, specifically the nucleus tractus solitarii (NTS). Here, we combine MRI assessment of gastric kinematics with measures of NTS functional connectivity to the brain in patients with FD and healthy controls (HC), in order to elucidate how gut-brain axis communication is associated with FD pathophysiology.

METHODS

Functional dyspepsia and HC subjects experienced serial gastric MRI and brain fMRI following ingestion of a food-based contrast meal. Gastric function indices estimated from 4D cine MRI data were compared between FD and HC groups using repeated measure ANOVA models, controlling for ingested volume. Brain connectivity of the NTS was contrasted between groups and associated with gastric function indices.

KEY RESULTS

Propagation velocity of antral peristalsis was significantly lower in FD compared to HC. The brain network defined by NTS connectivity loaded most strongly onto the Default Mode Network, and more strongly onto the Frontoparietal Network in FD. FD also demonstrated higher NTS connectivity to insula, anterior cingulate and prefrontal cortices, and pre-supplementary motor area. NTS connectivity was linked to propagation velocity in HC, but not FD, whereas peristalsis frequency was linked with NTS connectivity in patients with FD.

CONCLUSIONS & INFERENCES

Our multi-modal MRI approach revealed lower peristaltic propagation velocity linked to altered brainstem-cortical functional connectivity in patients suffering from FD suggesting specific plasticity in gut-brain communication.

Selected personality traits and emotional disorders of women diagnosed with gastrointestinal disease - a pilot study

Introduction

There are many studies on the influence of psychological factors in the appearance of symptoms and their treatment among gastroenterological patients. It is increasingly indicated that these factors are of great importance also for the quality of life of people struggling with a chronic disease.

Aim

To evaluate personality traits and emotional disorders in female patients with gastrointestinal conditions such as functional dyspepsia (FD), irritable bowel syndrome (IBS), or inflammatory bowel disease (IBD).

Material and methods

The sample of 28 patients was verified in terms of the disease using the GAST questionnaire and assessed by personality questionnaires and psychological tests: the Spielberger State-Trait Anxiety Inventory (STAI), EAS Temperament Survey, Eysenck Personality Inventory (EPQ-R), Coping Inventory for Stressful Situations (CISS); Beliefs about Pain Control Questionnaire (BPCQ), General Self-efficacy Scale (GSES), and Satisfaction with Life Scale (SWLS).

Results

The control group was recruited from female university students declaring full health. The conducted statistical analysis showed that there is a significant relationship between personality traits, psychological predispositions, and both the experience of illness and satisfaction with life among this specific group of patients.

Conclusions

This pilot study demonstrated the need for a personalized approach to gastroenterological patients, also based on their personality characteristics. Such an approach may increase the effectiveness of therapy and bring benefits in long-term treatment.

Altered Resting Brain Functions in Patients With Irritable Bowel Syndrome: A Systematic Review

Background

The neural activity of irritable bowel syndrome (IBS) patients in the resting state without any intervention has not been systematically studied. The purpose of this study was to compare the resting-state brain functions of IBS patients with healthy controls (HCs).

Methods

The published neuroimage studies were obtained from electronic databases including PubMed, EMBASE, PsycINFO, Web of Science Core, CNKI Database, Wanfang Database, VIP Database, and CBMdisc. Search dates were from inception to March 14th, 2022. The studies were identified by the preidentified inclusion and exclusion criteria. Two independent reviewers compiled the studies and evaluated them for quality and bias.

Results

Altogether 22 fMRI studies were included in this review. The risk of bias of the included studies was generally low. The findings indicated that in IBS patients, increased or decreased brain areas were mostly associated with visceral sensations, emotional processing, and pain processing. According to brain network research, IBS may exhibit anomalies in the DMN, CEN, and emotional arousal networks. The fluctuations in emotion (anxiety, sadness) and symptoms in IBS patients were associated with alterations in the relevant brain regions.

Conclusion

This study draws a preliminary conclusion that there are insufficient data to accurately distinguish the different neurological features of IBS in the resting state. Additional high-quality research undertaken by diverse geographic regions and teams is required to reach reliable results regarding resting-state changed brain regions in IBS.

Cerebral Metabolic Analysis of Patients With Colorectal Cancer and Chronic Enteritis: Inquiry Into Gut-Brain Crosstalk

Gut-brain crosstalk has been demonstrated previously. However, brain metabolic patterns of colorectal cancer and chronic enteritis remain unclear. A better understanding of gut-brain crosstalk from a radiological perspective is necessary. We conducted a retrospective study in which we acquired ¹⁸F-fluorodeoxyglucose positron emission tomography in 45 colorectal cancer cases, 45 age- and sex-matched chronic enteritis patients, and 45 age- and sex-matched healthy controls. We calculated a scaled sub-profile pattern based on principal component analysis and metabolic connectivity to explore the brain metabolic model and analyzed correlations between various brain regions and cancer to identify potential neuroimaging markers for non-pharmaceutical therapies. We found a characteristic cerebral metabolic pattern in colorectal cancer patients, which mainly involved visceral sensation and both affective and cognitive psychological processes. The metabolic patterns of patients with colorectal cancer and chronic enteritis were similar but not identical. The metabolic connectivity of the postcentral gyrus and paracentral lobule was found to be significantly different between the controls and patients with colorectal cancer (p < 0.05, false discovery rate correction). The maximal standard uptake value of the cancer focus in colorectal cancer patients was negatively correlated with the dorsolateral superior frontal gyrus (p < 0.05). Patients with colorectal cancer may show abnormal glucose cerebral metabolism characterized by “point-line-surface.” This preliminary study revealed the cerebral metabolic characteristics and neurobiological mechanisms of colorectal cancer and chronic enteritis (ChiCTR2000041020; registered December 16, 2020).