Inter- and Intrasubject Variability of Total Gastric Volumes in Response to Isocaloric Liquid Meals in Functional Dyspepsia and Health

Abstract

Aims: Measurement of gastric emptying by scintigraphy, ultrasound or breath test has a considerable interindividual variability. However, data on the reproducibility of non-invasive total gastric volume measurements are sparse. Aims: To compare gastric volume responses to ingestion of isocaloric liquid meals and document the inter- and intraindividual reproducibility of gastric volume measurement using a validated MRI technique in patients with functional dyspepsia (FD) and healthy controls (HC). Methods: 8 healthy controls and 8 dyspeptic patients underwent a MRI study on two different occasions after an eight hour fast. MR images of the gastric region were acquired in seated position in a 0.5T open configuration MR system before and at regular intervals until 120 minutes after administration of a liquid meal (200ml, 300 kcal), labeled with 500µmol/l Gd-DOTA. Meal emptying curves were fitted to a non-linear model. Total gastric volumes before (V0) and immediately after meal ingestion (V1) and meal half-emptying times (T½ meal) were determined. The coefficient of variation for inter- and intrasubject variability (CVinter, CVintra) of these parameters and Pearsons correlation coefficient of intraindividual measurements (expressed as r2) were calculated. Bland–Altman plot displayed data on repeated studies and paired t-test compared total gastric volumes and T½ meal. Results: T½ meal (mean±SD) on the two occasions were 113±28 and 121±30 min for HC and 127±31 and 128±37 min for FD (n.s.). For controls, CVinter[%]/CVintra[%]/r2 were 31/23/0.24 for total gastric volume in fasting condition (V0), 13/7/0.46 for total gastric volume immediately after meal ingestion (V1) and 25/7/0.80 for T1/2 meal. For patients with FD these parameters were for V0: 42/41/0.01, for V1: 18/10/0.16 and for T1/2 meal: 26/10/0.70. SUMMARY: Stomach volumes in fasting condition show a considerable intersubject and day-to-day variability within subjects. Nevertheless, there is a high intraindividual reproducibility for total gastric volume measurements after meal ingestion and for meal emptying half-times. Conclusions: These findings show that the stomach accommodates to the ingested meal, resulting in similar postprandial total gastric volumes within and between subjects.