Magnetic Resonance Imaging (MRI) Fat Quantification of the Liver

Study Overview
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Brief Summary
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Fatty liver in the obese is a common finding; some cases develop steato-hepatosis which in the long-term can lead to liver cirrhosis. The effect of bariatric surgery on fat distribution in the liver has so far been studied with liver biopsies and single voxel MR techniques. With this trial investigators present a new, whole organ MR-quantification of liver fat and describe changes after bariatric surgery in visceral and subcutaneous fat.

Detailed Description
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Currently, liver biopsy is still regarded as the gold-standard in the diagnosis of non-alcoholic fatty liver disease and monitoring of progression. However, accuracy of diagnosis is not perfect with a certain risk of sampling error depending on biopsy quality and a more or less homogeneous distribution of liver tissue alterations. Complications are rare; however, the method is invasive and carries the risk of bleeding. Therefore, non-invasive methods (such as serum biomarkers or imaging techniques) are sought for accurate diagnosis and safe monitoring of disease progression. Unidimensional transient elastography (TE; FibroScan®) is a non-invasive technique, which can be a helpful tool here: however, accuracy of diagnosis is depending on the stage of fibrosis and lower grades of fibrosis (stage 1 and 2) are difficult to assess. Moreover, in obese patients this method cannot be applied. In recent years, the development of fat-water magnetic resonance imaging has enabled non-invasive assessment of fat and water content in tissues. In addition, modern MRI devices allow brief breath holding, which reduces motion artifacts and provides us with excellent data and therefore MRI has become an important tool for fat quantification. Up to date only a few studies have focused on fat quantification before and after bariatric surgery: patients treated with laparoscopic gastric banding (a purely restrictive procedure) and patients undergoing metabolic surgery such as sleeve gastrectomy and gastric bypass have been examined pre- and postoperatively by means of MRI fat quantification. However, in these studies single voxel spectroscopy was used. In contrast, in this current trial investigators aim to assess full organ volume, which hopefully will provide more accurate data.

Official Title
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MRI Fat Quantification of the Liver, Subcutaneous and Visceral Fatty Tissue in Patients Before and After Bariatric Surgery

Conditions
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Non-alcoholic Fatty Liver Disease, Obesity

Intervention / Treatment
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* Other: MR Abdomen


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: morbidly obese patients with BMI over 35, scheduled for bariatric surgery (either sleeve gastrectomy or gastric bypass) Exclusion Criteria: Smoking substance abuse Diabetes history of gastrointestinal disorders pace-maker claustrophobia

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 60 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Laparoscopic gastric bypass<br>MR Abdomen in morbidly obese patients receiving gastric bypass | Other: MR Abdomen<br> <br> |
| Active Comparator: Laparoscopic sleeve gastrectomy<br>MR Abdomen morbidly obese patients receiving sleeve gastrectomy | Other: MR Abdomen<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Liver fat quantification | change in fat quantification; measurement of fat rate in the organ | within 3, 6 and 12 months of surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Visceral fat quantification | change in fat quantification visceral; 2-point Dixon technique for volumetric fat imaging | within 3, 6 and 12 months of surgery | 
| Subcutaneous fat quantification | change in fat quantification subcutaneous; 2-point Dixon technique for volumetric fat imaging | within 3, 6 and 12 months of surgery |