Non‐uniform gastric wall kinematics revealed by 4D Cine magnetic resonance imaging in humans

Abstract

Background Assessment of gastric function in humans has relied on modalities with varying degrees of invasiveness, which are usually limited to the evaluation of single aspects of gastric function, thus requiring patients to undergo a number of often invasive tests for a full clinical understanding. Therefore, the development of a non‐invasive tool able to concurrently assess multiple aspects of gastric function is highly desirable for both research and clinical assessments of gastrointestinal (GI) function. Recently, technological advances in magnetic resonance imaging (MRI) have provided new tools for dynamic (or “cine”) body imaging. Such approaches can be extended to GI applications. Methods In the present work, we propose a non‐invasive assessment of gastric function using a four‐dimensional (4D, volumetric cine imaging), free‐breathing MRI sequence with gadolinium‐free contrast enhancement achieved through a food‐based meal. In healthy subjects, we successfully estimated multiple parameters describing gastric emptying, motility, and peristalsis propagation patterns. Key Results Our data demonstrated non‐uniform kinematics of the gastric wall during peristaltic contraction, highlighting the importance of using volumetric data to derive motility measures. Conclusions & Inferences MRI has the potential of becoming an important clinical and gastric physiology research tool, providing objective parameters for the evaluation of impaired gastric function.

Automatic assessment of human gastric motility and emptying from dynamic 3D magnetic resonance imaging

“…29 In a recent paper (submitted for publication around the same time as this paper), Sclocco and colleagues introduced a semi-automated processing protocol to quantify gastric emptying and motility indices from 4D cine MRI of the stomach. 30 In their study, the first MRI volume in each session was manually segmented; subsequent volumes…”

“…31 A bright intra-gastric intensity is essential to facilitate automated image segmentation. While the most common contrast meal used in gastric MRI studies is a soupbased diet or caloric liquid nutrient (eg, Ensure) with the addition of paramagnetic MRI contrast agents (eg, gadolinium chelates), 32 some studies have proposed to use naturalistic contrast meal such as blueberry or pineapple juice because they contain a high level of manganese 30,33,34 ; the use of naturalistic contrast meal is advantageous because it avoids potential safety concerns of an otherwise fabricated contrast agent. Here, we identified that firm tofu is also a high manganese food that contains 1.2 mg of manganese per 100 g tofu.…”

“…However, when imaging continuously with a free-breathing protocol, respiration often causes bulk motion, disturbs image quality, and confounds motility assessment. To mitigate this challenge, potential solutions rely on either off-line processing 38 or pulse sequences 30,39 for online correction. In this study, we explored the off-line approach for motion correction.…”

“…It is also noteworthy that our MRI data was acquired with isotropic spatial resolution (ie, 1.9 mm) rather than thick-slice image acquisition protocols that are typically used in other gastric MRI studies. 30,40 Isotropic image acquisition not only reduces partial volume effect but can also facilitate more accurate 3D reconstruction of the stomach, which are both critical for surface-based motility analysis. It is foreseeable that a similar analysis may be developed for quantification of lower GI motility, to complete the methodological framework for assessing the physiology and pathological changes in the complete GI system.…”

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

“…However, no study to date has directly linked mechanoreceptive gastric afference, approximated by MRI metrics of gastric kinematics, to brainstem viscerosensory connectivity in patients with FD. In this study, we combined our previously validated 4D cine MRI gastric imaging technique 17 with brain fMRI in order to examine stomach function and the central processing of gastric afference in FD.…”