Assessment of gastric motor function by cine magnetic resonance imaging

Background and Aim: The aim of the present study was to evaluate gastric motor function by magnetic resonance imaging (MRI) and investigate whether this examination is a useful tool for therapeutic efficacy or postoperative gastric motor function. Methods: Twenty-five healthy volunteers and 10 gastric cancer patients with pylorus-preserving gastrectomy (PPG) underwent cine-MRI. Gastric volume was determined by 3D-volumetry. Gastric motility was quantified by calculating the gastric motility index (GMI). Results: The image acquisition and analysis were successfully carried out for all subjects. In healthy volunteers, mean frequency, amplitude, velocity of gastric peristaltic waves and GMI 30 min after the intake of jelly were 3/min, 8.8 mm, 2.2 mm/s and 19.6 mm(2)/s, respectively. Mean amplitude (8.8 vs 10.4 mm, P = 0.027), velocity (2.2 vs 2.6 mm/s, P < 0.001) of peristaltic waves, and GMI (19.6 vs 26.7 mm(2)/s, P < 0.001) significantly increased at 30 min after giving mosapride citrate (MS). Mean gastric volume after MS administration was significantly decreased; 0 min (317.3 vs 272.9 mL, P = 0.021), 45 min (263.4 vs 206.4 mL, P = 0.004) and 60 min (228.7 vs 165 mL, P = 0.001). PPG patients with postprandial symptoms were observed having antiperistalsis-like contraction waves and reflux of gastric contents from the pyloric region into the upper part of the stomach. Mean gastric volume in PPG patients with postprandial symptoms at 30 min after intake of jelly tended to be greater than in those without such symptoms. Conclusions: The present study demonstrates that cine-MRI is a sensitive and non-invasive imaging technique for simultaneously measuring gastric motility and emptying.