A review of recent developments in the imaging of disorders of gut-brain interaction

Abstract

A number of factors have been recently associated with the development of disorders of gut-brain interaction (DGBI), including genetic predisposition, early-life environment, intestinal microbiota, infection, microinflammation, and increased mucosal permeability. In addition, impaired gastrointestinal motility is important not only as a cause of DGBI but also as a consequent final phenotype. Gastrointestinal motor measurements are the predominant method for the assessment of and therapeutic intervention into motor abnormalities. As such, these measurements should be considered for DGBI patients who do not respond to first-line approaches such as behavioral therapy, dietary modifications, and pharmacotherapy. This comprehensive review focuses on the functional changes in the upper gastrointestinal tract caused by DGBI and describes ongoing attempts to develop imaging modalities to assess these dysfunctions in the esophageal and gastric regions. Recent advances in imaging techniques could help elucidate the pathophysiology of DGBI, with exciting potential for research and clinical practice.

Keywords: cine MRI; disorders of gut-brain interaction; endoscopic ultrasonography; onigiri esophagography; transnasal endoscopy.

Fig. 1.

Evaluation of esophageal wall motion after jelly swallowing. Esophageal wall motion was classified into resting, distension, contraction, and relaxation phases, and esophageal muscle layers were measured by classifying them as circular or longitudinal smooth muscle. Changes over time were analyzed, along with the esophageal lumen area.

Fig. 2.

A representative series of barium onigigography with obstruction level 0–4. White arrows indicate the upper level of the swallowed onigiri or liquid barium. White outlined arrows indicate the lower level of swallowed onigiri. OL: Obstruction level.

Fig. 3.

Comparison of the proportion of obstruction levels between functional dysphagia and healthy groups. OL: obstruction level.

Fig. 4.

Evaluation of gastric peristalsis using cine magnetic resonance imaging. A. Magnetic resonance imaging (MRI) of a healthy control in the preprandial state. The short-axis diameter of the stomach was small and no gastric peristalsis was observed. B., C. MRI image of a healthy control in the postprandial state. Compared with the preprandial state, both the short-axis diameter of the stomach and peristaltic activity of the antrum and body were greater. D. MRI image of a functional dyspepsia patient in the preprandial state. The short-axis diameter of the stomach was small and no gastric peristalsis was observed. E. MRI image of a functional dyspepsia patient in the postprandial state. Compared with those of a postprandial healthy control patient, the short-axis diameter of the stomach was smaller and gastric peristaltic activity was lower.