Measurement of proximal and distal gastric motility with magnetic resonance imaging

Abstract

The precise motor mechanisms associated with gastric emptying of nutrient liquids are unclear, in part because of difficulties in measuring the motility from the proximal and distal stomach simultaneously. We have now examined proximal and distal gastric motility, using a novel magnetic resonance imaging (MRI) technique. In seven healthy volunteers (4 males, 3 females; 27-37 yr), gastric emptying and motility were determined on two occasions after ingestion of 500 ml 10% and 25% dextrose labeled with 1 mM gadolinium tetraazacyclododecane tetraacetic acid, using a 1.5-tesla Philips Gyroscan ACS II scanner. Gastric emptying was determined every 15 min with a series of transaxial scans. After each series of transaxial scans, 120 coronal scans, 1.2 s apart, were performed through the antrum and proximal stomach. For each coronal slice the diameters of the proximal stomach and the antrum were measured to determine the number of contractions per minute and depth (%basal diameter). Gastric emptying (half-emptying time) was faster after ingestion of 10% compared with 25% dextrose (49 +/- 15 vs. 118 +/- 37 min; P < 0.01). After both meals, the diameter of the proximal stomach remained relatively constant, whereas there were marked fluctuations in the diameter of the antrum. Mean (+/- SD) frequency (2.8 +/- 0.6 vs. 2.0 +/- 0.8/min; P < 0.001) and depth (40 +/- 17% vs. 34 +/- 16%; P < 0.04) of antral contractions were higher after 10% dextrose compared with 25% dextrose. Rapid MRI techniques allow simultaneous measurement of both gastric emptying and motor function of different gastric regions. The increase in the frequency and depth of distal gastric contractions during ingestion of 10% compared with 25% dextrose supports the concept that the antrum contributes to the regulation of gastric emptying of nutrient liquids.

Exploring gastrointestinal variables affecting drug and formulation behavior: Methodologies, challenges and opportunities

“…Cine-MRI can image the GI tract with sufficient speed to visualize motility. This can be done on the stomach looking at antral motility frequency and amplitude (Kunz et al, 1998;Marciani et al, 2001;Schwizer et al, 1994Schwizer et al, , 1996Wright et al, 1999). More recently, the technique has been extended to the small bowel (Hahnemann et al, 2015;Menys et al, 2014;Odille et al, 2012) and to the colon (Buhmann et al, 2005;Menys et al, 2014).…”

Hydro-MRI for the visualization of gastric wall motility using RARE magnetic resonance imaging sequences

“…Current functional imaging techniques of the stomach are based on barium-contrast X-ray [7], ultrasonography [8,9] and contrast-enhanced MRI [1][2][3][4]. Excellent anatomical and temporal resolution is achieved by barium X-ray studies.…”

“…This MR technique is mainly based on the positive contrast of ingested superpara-(e.g., ferumoxides) or paramagnetic (e.g., Gd-DOTA) contrast agents, and several protocols have been proposed in literature [1][2][3][4]. Alternatively, the use of ingested intralipids has been reported.…”

“…For positive contrast, these studies used contrast agents including gadolinium complexes [1][2][3][4] or lipid-containing meals [2]. Under these circumstances ultrafast imaging was performed with strongly T1-weighted types of imaging sequences.…”

Validation of a rapid, semiautomatic image analysis tool for measurement of gastric accommodation and emptying by magnetic resonance imaging

“…Magnetic resonance (MR) imaging (MRI) provides wide-field, three-dimensional (3D) images with excellent soft tissue contrast without the use of harmful ionizing radiation. Researchers have developed and validated MRI techniques to assess a wide range of digestive functions such as gastric accommodation, motility, and emptying (2,3,7,8,13,18,20,24,25,(27)(28)(29)(30)(31). Recent studies have applied these techniques to gain insight into the pathophysiology of gastroesophageal reflux disease (11, 19), dyspepsia (13, 14, 34), gastric emptying disorders (2,7,24), and the irritable bowel syndrome (15,23).…”