Gastric Emptying Validation Pilot Study (MRI Val) (MRIVal)

A Pilot, Validation Study to Assess Sequential MRI Scanning on a 0.5 Tesla Upright Scanner as a Method to Determine Gastric Emptying Rate

The primary aim of this study is to assess (in healthy volunteers) the rate at which a glucose drink leaves the stomach by sequential magnetic resonance imaging (MRI) of the stomach contents using a 0.5 tesla upright MRI scanner, and comparing with the rate derived from a standard method which uses a stable isotope tracer and breath testing. The main question it aims to answer are:

• Do MRI derived images of stomach contents at low magnetic field (0.5 Tesla) have sufficient resolution to provide a reproducible assessment of gastric emptying
• What is the agreement and relationship between the rate of gastric emptying determined from the 2 methods Participants will be asked to attend the imaging centre on one occasion in the morning after fasting from midnight and to sit within an upright MRI scanner for a period of approximately 140 minutes. Images of their stomach will be taken before and for 2 hours after consuming a drink containing glucose and a small amount of sodium acetate which contains a heavier form of carbon. Before each image is taken, participants will be asked to exhale into a 500ml bag to collect a breath sample.

Study Overview

• Status: Completed
• Conditions: Gastrointestinal Dysfunction
• Intervention / Treatment: Diagnostic test: Oral glucose tolerance test

Detailed Description

The rate at which food empties from the stomach is a key assessment made in appetite and metabolic research, as well as studies investigating gastrointestinal function in health and disease. This assessment can be achieved by measuring the volume of the stomach contents at timepoints after eating using magnetic resonance imaging (MRI) and calculating the gastric emptying rate from the decrease in volume which occurs over time. However, these measures are traditionally made when the individual is lying supine within the bore of the MRI machine and this postural position may impact the rate that food empties from the stomach. A low-field 0.5 Tesla 'upright' MRI scanner could address the problem of measuring gastric emptying rate when supine. However, the resolution of the images obtained are poorer than those obtained at higher field strengths (e.g. at 3 Tesla). The primary aim of this study is to compare gastric emptying kinetics assessed by sequential MR imaging of the stomach with a standard method which uses a stable isotope tracer (13-Carbon labelled sodium acetate) and breath testing. Twelve healthy, non-obese volunteers (18 to 60 years old) will attend the imaging centre on one occasion in the morning after fasting from midnight and sit within an upright MRI scanner for a period of approximately 140 minutes. Images of their stomach will be taken before and every 5 minutes for 1 hour, and every 10 minutes for the following hour, after consuming a drink containing glucose and 150mg of sodium acetate which contains a heavier (non-radioactive) form of carbon (carbon-13). Before each image is taken, participants will exhale into a 500ml bag to enable a breath sample to be collected. Breath samples will subsequently be analysed for carbon-13 enrichment of expired carbon dioxide (CO2) using mass spectrometry.

• Study Type: Observational
• Enrollment (Actual): 12
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United Kingdom
  • Notts
    • Nottingham, Notts, United Kingdom, NG72UH
      • Sir Peter Mansfield Imaging Centre

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 60 years (Adult)
• Accepts Healthy Volunteers: Yes

• Sampling Method: Non-Probability Sample

Study Population

Healthy male and female adults

Description

Inclusion Criteria:

• Healthy (health status will be confirmed at screening).
• Able to fully comprehend the informed consent process and give informed consent.
• BMI <30 kg/m2

Exclusion Criteria:

• Known contraindication to MRI scanning (for example, pacemaker/implanted defibrillator, aneurysm clips, implanted programmable device, intra-ocular metallic fragment, claustrophobia)
• Major psychiatric, cognitive or mood disorder.
• Any other significant chronic medical conditions, including diabetes (type 1 and 2), asthma and epilepsy.
• Any acute major illness or surgery within one year prior to participation.
• Glucose intolerance (as assessed by a finger-prick test at screening).
• Having taken part in a research study in the last 3 months involving invasive procedures, ionising radiation or an inconvenience allowance.

Study Plan

How is the study designed?

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Healthy adults; Healthy male and female participants	Diagnostic test: Oral glucose tolerance test; A drink containing 75g of glucose together with 150mg carbon-13 sodium acetate in 300ml water

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
MRI gastric emptying rate (T50)	Gastric emptying rate (ml/min) derived from the decrease in volume of gastric contents	assessment made over 120 minutes (timepoints from 0 minutes to 120 minutes after consuming test drink)
13-Carbon labelled Sodium Acetate Breath test gastric emptying rate (T50)	Gastric emptying rate derived (ml/min) from the rate of appearance of carbon 13 labelled CO2 in the breath	assessment made over 120 minutes (timepoints from 0 minutes to 120 minutes after consuming test drink)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Volume of gastric contents	Volume of gastric contents determined from MRI images (ml)	assessed at timepoints from 0 minutes to 120 minutes after consuming the test drink (timepoints 0,5,10,15,20,25,30,35,40,45,50,55,60,70,80,90,100,110,and 120 minutes)
Carbon 13-enrichment of breath CO2	carbon 13 labelled CO2 content in the breath measured using mass spectrometry	assessed at timepoints from 0 minutes to 120 minutes after consuming the test drink (timepoints 0,5,10,15,20,25,30,35,40,45,50,55,60,70,80,90,100,110,and 120 minutes)

Collaborators and Investigators

• Sponsor: University of Nottingham
• Investigators: Principal Investigator: Luca Marciani, PhD, University of Nottingham

Study record dates

Study Major Dates

• Study Start (Actual): October 1, 2022
• Primary Completion (Actual): March 28, 2023
• Study Completion (Actual): March 28, 2023

Study Registration Dates

• First Submitted: February 16, 2023
• First Submitted That Met QC Criteria: February 28, 2023
• First Posted (Actual): March 13, 2023

Study Record Updates

• Last Update Posted (Actual): July 13, 2023
• Last Update Submitted That Met QC Criteria: July 11, 2023
• Last Verified: July 1, 2023

More Information

Terms related to this study

• Keywords: Magnetic resonance imaging; gastric emptying; '13-C acetate' breath test
• Other Study ID Numbers: 40-0822

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: anonymised data only shared where specific consent for data use in further studies has been given by the participants

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No