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

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.