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Abstract #4015

Empirical Modeling of B1 Inhomogeneity Correction for Absolute Quantitation of Hepatic Glycogen Using Non-Localized 13C MRS

Navin Michael1, Pola Arunima2, Sendhil S. Velan2, 3, Adam Schwarz4

1Singapore Institute for Clinical Sciences, 30 , Medical Drive, Singapore; 2Singapore Institute for Clinical Sciences, 30, Medical Drive, Singapore; 3Clinical Imaging Research Centre, 14, Medical Drive, Singapore; 4Eli Lilly and Company, Indianapolis, IN, United States

The different thickness of subcutaneous fat is a confounding factor in the absolute quantitation of hepatic glycogen using non localized 13C spectroscopy, due to the B1 field inhomogeneity of the 13C surface coils.This makes the comparison of glycogen levels across different subjects difficult. In this work, a new empirical B1 correction model is proposed that can be used to compensate the effect of the B1 inhomogeneity for different coil-liver distances. The proposed model has the advantage of being easily incorporated into post-processing protocols and does not require additional B1 field mapping sequences during the in-vivo scans.

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Keywords

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