Reported abdominal pain is associated with gastric motility in functional dyspepsia patients

Abstract

Functional dyspepsia (FD) is a common gastrointestinal (GI) disorder of the upper GI tract associated with a variety of symptoms, such as abdominal pain and bloating, but lacking identifiable organic abnormalities. Altered motility patterns in FD occur in the stomach, pylorus and small intestine during digestive or interdigestive periods, and up to 30% of symptoms are associated with migrating motor complexes-like activity, thus suggesting a link between gastric motility and sensory disturbances. However, gastric functional impairments have proven to be challenging to assess using conventional abdominal imaging, which typically evaluated anatomy at a single time point and relied on a variety of modalities with varying degrees of invasiveness. Magnetic Resonance Imaging (MRI) represents a promising tool for non-invasive assessment of multiple aspects of gastric function, which can be linked with pain intensity. We applied a novel 4D (volume + time), free-breathing MRI sequence at 3T with contrast enhancement achieved through a food-based meal in order to assess human gastric function. Twelve (12) FD patients were asked to consume a high-caloric meal (470 ml semi-solid pudding) containing pineapple as contrast agent. 4D cine-MRI gastric scans were collected continuously for 5 minutes (temporal resolution: 7s) at 3 post-meal times (+15, +45, +75 minutes). Ratings of abdominal pain were collected prior to each scan using a numerical rating scale ranging from 0 (“unnoticeable”) to 100 (“unbearable”). MRI gastric volumes were segmented and a gastric motility index was extracted by dividing gastric wall deformation by gastric volume. This index showed a significant positive correlation with abdominal pain ratings (r=0.39, p-value=0.018). No significant correlations were found between abdominal pain and gastric volume or ingested meal volume, supporting the importance of dynamic gastric measurements. Our results support 4D cine-MRI as a clinically relevant tool for the identification of gastric abnormalities associated with FD symptomatology. NIH NIDDK R21-DK116029, NIH Office Of The Director OT2-OD023867.