Fast Absolute Quantification of In Vivo Water and Fat Content with Magnetic Resonance Imaging

Abstract

Quantitative water fat imaging offers a non-invasive method for monitoring and staging diseases associated with changes in either water or fat content in tissue. In this work absolute water and fat mass density measurement with in vivo Magnetic Resonance Imaging (MRI) is demonstrated. T1 independent, T2* corrected chemical shift based water-fat separated images are acquired. By placing a phantom with known mass density in the field of view for signal intensity calibration, absolute water or fat mass density can be computed, assuming the B1+ (transmit) and B1- (receive) fields can be measured. Phantom experiments with known water fat concentration were conducted to validate the feasibility of proposed method and in vivo data was collected from healthy volunteers. Results show good agreement with known values of in vivo water density. Each measurement was within one breath hold. Fast absolute quantification of water and fat with MRI is feasible in the abdomen