Abstract #4258

Optimization of Saturation Pulse Length in Parallel Transmission Based Amide Proton Transfer MRI for Oncology Applications

Jochen Keupp¹, Osamu Togao², Jinyuan Zhou³, Yuriko Suzuki⁴, Takashi Yoshiura²

¹Philips Research, Hamburg, Germany; ²Department of Clinical Radiology, Kyushu University, Fukuoka, Japan; ³Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, MD, United States; ⁴Philips Electronics Japan, Tokyo, Japan

Amide proton transfer (APT) offers a novel route to sensitive MR molecular imaging of endogenous cytosolic proteins and is expected to play an important role in delineation/classification of active tumor tissue for therapy planning/monitoring. The length of RF saturation (T_sat) is a key for sensitivity, in particular at low protein concentrations. With novel parallel transmission based techniques, T_sat>1s is possible on clinical scanners. A thorough protocol optimization is needed for tumor contrast and contrast-to-noise ratio. In a phantom study and acquiring first exemplary clinical brain tumor data, the effect of T_sat on the APT contrast is studied in the range of T_sat=0.5s up to 4s.