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Methodological and physiological test-retest reliability of 13 C-MRS glycogen measurements in liver and in skeletal muscle of patients with type 1 diabetes and matched healthy controls

2016; Wiley; Volume: 29; Issue: 6 Linguagem: Inglês

10.1002/nbm.3531

1099-1492

Tania Buehler, Lia Bally, Ayşe Sıla Dokumacı, Christoph Stettler, Chris Boesch,

Cardiovascular Function and Risk Factors

NMR in BiomedicineVolume 29, Issue 6 p. 796-805 Research article Methodological and physiological test–retest reliability of 13C-MRS glycogen measurements in liver and in skeletal muscle of patients with type 1 diabetes and matched healthy controls Tania Buehler, Tania Buehler Department of Clinical Research and Department of Radiology, University of Bern, SwitzerlandLia Bally and Tania Buehler share first authorship.Search for more papers by this authorLia Bally, Lia Bally Division of Endocrinology, Diabetes and Clinical Nutrition, Inselspital Bern, SwitzerlandLia Bally and Tania Buehler share first authorship.Search for more papers by this authorAyse Sila Dokumaci, Ayse Sila Dokumaci Department of Clinical Research and Department of Radiology, University of Bern, SwitzerlandSearch for more papers by this authorChristoph Stettler, Christoph Stettler Division of Endocrinology, Diabetes and Clinical Nutrition, Inselspital Bern, SwitzerlandSearch for more papers by this authorChris Boesch, Corresponding Author Chris Boesch orcid.org/0000-0001-8498-8543 Department of Clinical Research and Department of Radiology, University of Bern, Switzerland Correspondence to: Chris Boesch, Department of Clinical Research and Department of Radiology, University of Bern, Switzerland. E-mail: chris.boesch@insel.chSearch for more papers by this author Tania Buehler, Tania Buehler Department of Clinical Research and Department of Radiology, University of Bern, SwitzerlandLia Bally and Tania Buehler share first authorship.Search for more papers by this authorLia Bally, Lia Bally Division of Endocrinology, Diabetes and Clinical Nutrition, Inselspital Bern, SwitzerlandLia Bally and Tania Buehler share first authorship.Search for more papers by this authorAyse Sila Dokumaci, Ayse Sila Dokumaci Department of Clinical Research and Department of Radiology, University of Bern, SwitzerlandSearch for more papers by this authorChristoph Stettler, Christoph Stettler Division of Endocrinology, Diabetes and Clinical Nutrition, Inselspital Bern, SwitzerlandSearch for more papers by this authorChris Boesch, Corresponding Author Chris Boesch orcid.org/0000-0001-8498-8543 Department of Clinical Research and Department of Radiology, University of Bern, Switzerland Correspondence to: Chris Boesch, Department of Clinical Research and Department of Radiology, University of Bern, Switzerland. E-mail: chris.boesch@insel.chSearch for more papers by this author First published: 13 April 2016 https://doi.org/10.1002/nbm.3531Citations: 11 Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat Abstract Glycogen is a major substrate in energy metabolism and particularly important to prevent hypoglycemia in pathologies of glucose homeostasis such as type 1 diabetes mellitus (T1DM). 13C-MRS is increasingly used to determine glycogen in skeletal muscle and liver non-invasively; however, the low signal-to-noise ratio leads to long acquisition times, particularly when glycogen levels are determined before and after interventions. In order to ease the requirements for the subjects and to avoid systematic effects of the lengthy examination, we evaluated if a standardized preparation period would allow us to shift the baseline (pre-intervention) experiments to a preceding day. Based on natural abundance 13C-MRS on a clinical 3 T MR system the present study investigated the test–retest reliability of glycogen measurements in patients with T1DM and matched controls (n = 10 each group) in quadriceps muscle and liver. Prior to the MR examination, participants followed a standardized diet and avoided strenuous exercise for two days. The average coefficient of variation (CV) of myocellular glycogen levels was 9.7% in patients with T1DM compared with 6.6% in controls after a 2 week period, while hepatic glycogen variability was 13.3% in patients with T1DM and 14.6% in controls. For comparison, a single-session test–retest variability in four healthy volunteers resulted in 9.5% for skeletal muscle and 14.3% for liver. Glycogen levels in muscle and liver were not statistically different between test and retest, except for hepatic glycogen, which decreased in T1DM patients in the retest examination, but without an increase of the group distribution. Since the CVs of glycogen levels determined in a “single session” versus “within weeks” are comparable, we conclude that the major source of uncertainty is the methodological error and that physiological variations can be minimized by a pre-study standardization. For hepatic glycogen examinations, familiarization sessions (MR and potentially strenuous interventions) are recommended. Copyright © 2016 John Wiley & Sons, Ltd. Citing Literature Volume29, Issue6June 2016Pages 796-805 RelatedInformation