The HRM predicts bolus movement more accurately than conventional manometry and identifies clinically relevant oesophageal dysfunction not detected by other investigations including conventional manometry.

No abstract

No abstract

The effects of macronutrients on gastric volume changes, emptying, and gastrointestinal symptoms are incompletely understood. Three liquid meals of 500 ml (fat emulsion, 375 kcal; protein solution, 375 kcal; glucose solution, 400 kcal) were infused into the stomach of 12 healthy volunteers on three occasions. Studies were performed in seated body position using an open-configuration magnetic resonance imaging (MRI) system. MRI imaging sequences, assessing stomach and meal volumes, were performed prior to and at times t = 0, 3, 6, 9, 12, 15, 25, 35, 45, 60, 75, and 90 min after meal administration. Areas under the curve for the early emptying phase (0-15 and 0-45 min) were calculated, and characteristics of the volume curves were analyzed by a gastric emptying model. Gastrointestinal symptoms were assessed by a self-report scale. Initial (t = 0 min) and early postprandial gastric volumes were highest for glucose because of lower initial emptying. However, in the early emptying phase the characteristics of the volume curves for stomach and meal were uniform for all macronutrients. Perceptions of fullness and satiety were linearly associated with postprandial gastric volumes, but not with macronutrient composition. Isovolumic macronutrient meals modulate gastric volume response by initial meal emptying patterns. Macronutrient specific accommodation responses, as shown in barostat studies, are not reflected as gastric volume responses under noninvasive conditions.

Purpose:To quantify healthy postprandial: 1) propagation, periodicity, geometry, and percentage occlusion by distal antral contraction waves (ACWs); and 2) changes in ACW activity in relationship to gastric emptying (GE).Materials and Methods: Using 1.5-T MR scanner, nine healthy fasted volunteers were examined in the right decubitus position after ingestion of 500 mL of 10% glucose (200 kcal) with 500 M Gd-DOTA. Total gastric (TGV) and meal volumes (MV) were assessed every five minutes for 90 minutes, in and interspersed with dynamic scan sequences (duration: 2.78 minutes) providing detailed images of distal ACWs.Results: TGV increased by 738 Ϯ 38 mL after ingestion (t 0 ), subsequently decreasing in parallel to GE. The mean GE rate and half-emptying time were 24 Ϯ 3 mL/5 minutes and 71 Ϯ 6 minutes, respectively. Accompanying ACWs reached a periodicity of 23 Ϯ 2 seconds at t 35 and propagated at an unvarying speed of 0.27 Ϯ 0.01 cm/second. Their amplitude of 0.70 Ϯ 0.08 cm was constant, but the width decreased along the antral wall by 6 Ϯ 2%/cm (P ϭ 0.003). ACWs were nonocclusive (percentage occlusion 58.1 Ϯ 5.9%, t 0 at the pylorus) with a reduction in occlusion away from the pylorus (P Ͻ 0.001). No propagation and geometry characteristics of ACWs correlated with the changes of MV (mL/5 minutes; R 2 Ͻ 0.05). Conclusion:Our results indicate that ACWs are not imperative for emptying of liquids. This study provides a detailed quantitative reference for MRI inquiries into pharmacologically-and pathologically-altered gastric motility.