Simultaneous Temperature Mapping in Fat and Water Using Two Point Dixon Hybrid PRF-T1 in 3D Segmented Flyback EPI

Mahamadou Diakite¹, Henrik Odeen¹, Nick Todd², Dennis L. Parker²

Accurate temperature mapping in tumor and surrounding tissue throughout a thermal therapy procedure is essential to ensure the safety and efficacy of the treatment. Methods based on the temperature dependency of the water proton resonance frequency (PRF) shift have shown the best ability to quantify temperature rises in aqueous tissues. Unfortunately, the PRF shift with temperature does not apply to lipid protons, since there is no hydrogen bonding among the methylene protons that supply the bulk of the fat signal. However, the temperature sensitivity of the spin-lattice relaxation time, T1, has been measured for a number of fatty tissues, and was found to obey a linear relationship with the temperature [1]. In the present work, we show a sequence implementation for 3D fat and water temperature imaging based on a Two Point Dixon (2PD) fat and water separation and the Variable Flip Angle (VFA) T1 mapping techniques [2].