Helen Parker1,2,3,4, Caroline L Hoad1,2,5, Emily Tucker1,2, Carolyn Costigan1,5, Luca Marciani1,2,5, Penny Gowland5, Mark Fox1,2,3. 1. NIHR Nottingham BRC, Nottingham University Hospitals NHS Trust and the University of Nottingham, Nottingham, UK. 2. Nottingham Digestive Diseases Centre, School of Medicine, University of Nottingham, Nottingham, UK. 3. Zürich Neurogastroenterology and Motility Research Group, Department of Gastroenterology and Hepatology, University Hospital Zürich, Zürich, Switzerland. 4. Institute of Health and Society, Newcastle University, Newcastle upon Tyne, UK. 5. Sir Peter Mansfield Imaging Centre, School of Physics and Astronomy, University of Nottingham, Nottingham, UK.
Abstract
BACKGROUND: Current investigations of gastric emptying rarely identify the cause of symptoms or provide a definitive diagnosis in patients with dyspepsia. This study assessed gastric function by magnetic resonance imaging (MRI) using the modular "Nottingham test meal" (NTM) in healthy volunteers (HVs). METHODS: The NTM comprises (a) 400 mL liquid nutrient (0.75 kcal/mL) labeled with Gadolinium-DOTA and (b) an optional solid component (12 agar-beads [0 kcal]). Filling sensations were documented. MRI measurements of gastric volume, emptying, contraction wave frequency, and secretion were obtained using validated methods. KEY RESULTS: Gastric function was measured in a population of 73 HVs stratified for age and sex. NTM induced moderate satiety and fullness. Labeled fluid was observed in the small bowel in all subjects after meal ingestion ("early-phase" GE). Secretion was rapid such that postprandial gastric content volume was often greater than meal volume (GCV0 > 400 mL), and there was increasing dilution of the meal during the study (P < 0.001). Gastric half-time was median 66-minutes (95% reference interval 35 to 161-minutes ["late-phase" GE]). The number of intact agar beads in the stomach was 7/12 (58%) at 60-minutes and 1/12 (8%) at 120-minutes. Age, bodyweight and sex had measurable effects on gastric function; however, these were small compared to inter-individual variation for most metrics. CONCLUSIONS AND INFERENCES: Reference intervals are presented for MRI measurements of gastric function assessed for the mixed liquid/solid NTM. Studies in patients will determine which metrics are of clinical value and also whether the reference intervals presented here offer optimal diagnostic sensitivity and specificity.
BACKGROUND: Current investigations of gastric emptying rarely identify the cause of symptoms or provide a definitive diagnosis in patients with dyspepsia. This study assessed gastric function by magnetic resonance imaging (MRI) using the modular "Nottingham test meal" (NTM) in healthy volunteers (HVs). METHODS: The NTM comprises (a) 400 mL liquid nutrient (0.75 kcal/mL) labeled with Gadolinium-DOTA and (b) an optional solid component (12 agar-beads [0 kcal]). Filling sensations were documented. MRI measurements of gastric volume, emptying, contraction wave frequency, and secretion were obtained using validated methods. KEY RESULTS: Gastric function was measured in a population of 73 HVs stratified for age and sex. NTM induced moderate satiety and fullness. Labeled fluid was observed in the small bowel in all subjects after meal ingestion ("early-phase" GE). Secretion was rapid such that postprandial gastric content volume was often greater than meal volume (GCV0 > 400 mL), and there was increasing dilution of the meal during the study (P < 0.001). Gastric half-time was median 66-minutes (95% reference interval 35 to 161-minutes ["late-phase" GE]). The number of intact agar beads in the stomach was 7/12 (58%) at 60-minutes and 1/12 (8%) at 120-minutes. Age, bodyweight and sex had measurable effects on gastric function; however, these were small compared to inter-individual variation for most metrics. CONCLUSIONS AND INFERENCES: Reference intervals are presented for MRI measurements of gastric function assessed for the mixed liquid/solid NTM. Studies in patients will determine which metrics are of clinical value and also whether the reference intervals presented here offer optimal diagnostic sensitivity and specificity.
Authors: Peng Du; Amelia Mazzone; Stefan Calder; Anna Qian; Simon J Gibbons; Gianrico Farrugia; Arthur Beyder Journal: Conf Proc IEEE Eng Med Biol Soc Date: 2019-07