3D Fast Spin Echo Acquisition for Combined Amide Proton Transfer and Elecric Properties Tomography

Mariya Doneva¹, Ulrich Katscher¹, Christian Stehning¹, Osamu Togao², Jochen Keupp¹

Amide proton transfer (APT) and electric properties tomography (EPT) are two novel MR methods for molecular and quantitative imaging of tissue properties. The APT signal is defined by the asymmetry of the magnetization transfer (MT) at +3.5ppm relative to water and reflects the concentration of endogenous cytosolic proteins or peptides as well as local pH. EPT is based on the curvature of the transceive phase (B1 field) of a fast spin echo (FSE) or balanced steady state free precession (bSSFP) image and reflects the electric conductivity of the tissue. Both elevated protein levels and tissue conductivity are related to pathological changes in tumors. Acquisition of the two contrasts in the same imaging sequence could potentially deliver complementary information for tumor tissue characterization and reduce the scan time compared to acquiring APT and EPT in separate scans. In this work, we propose an FSE acquisition, which allows the reconstruction of APT and EPT data from the same imaging sequence and demonstrate its feasibility in phantom and in vivo experiments.