title: Investigation of Readout RF Pulse Impact on the Chemical Exchange Saturation Transfer Spectrum.
abstract: Chemical exchange saturation transfer magnetic resonance imaging (CEST-MRI) is capable of both microenvironment and molecular imaging. The optimization of scanning parameters is important since the CEST effect is sensitive to factors such as saturation power and field homogeneity. The aim of this study was to determine if the CEST effect would be altered by changing the length of readout RF pulses. Both theoretical computer simulation and phantom experiments were performed to examine the influence of readout RF pulses. Our results showed that the length of readout RF pulses has unremarkable impact on the Z-spectrum and CEST effect in both computer simulation and phantom experiment. Moreover, we demonstrated that multiple refocusing RF pulses used in rapid acquisition with relaxation enhancement (RARE) sequence induced no obvious saturation transfer contrast. Therefore, readout RF pulse has negligible effect on CEST Z-spectrum and the optimization of readout RF pulse length can be disregarded in CEST imaging protocol.
authors.affiliation: Department of Biomedical Engineering and Environmental Sciences, National Tsing Hua University, Hsinchu 30013, Taiwan.
authors.forename: Sheng-Min
authors.initials: SM
authors.lastname: Huang
authors.affiliation: Health Physics Division, Institute of Nuclear Energy Research, Lungtan, Taoyuan 32546, Taiwan.
authors.forename: Meei-Ling
authors.initials: ML
authors.lastname: Jan
authors.affiliation: Health Physics Division, Institute of Nuclear Energy Research, Lungtan, Taoyuan 32546, Taiwan.
authors.forename: Hsin-Chin
authors.initials: HC
authors.lastname: Liang
authors.affiliation: Health Physics Division, Institute of Nuclear Energy Research, Lungtan, Taoyuan 32546, Taiwan.
authors.forename: Chia-Hao
authors.initials: CH
authors.lastname: Chang
authors.affiliation: Center for Advanced Molecular Imaging and Translation, Chang Gung Memorial Hospital, Taoyuan 333, Taiwan.
authors.forename: Yi-Chun
authors.initials: YC
authors.lastname: Wu
authors.affiliation: Graduate Institute of Applied Physics, National Chengchi University, Taipei 11605, Taiwan.|Research Center for Mind, Brain and Learning, National Chengchi University, Taipei 11605, Taiwan.
authors.forename: Shang-Yueh
authors.initials: SY
authors.lastname: Tsai
authors.affiliation: Department of Biomedical Engineering and Environmental Sciences, National Tsing Hua University, Hsinchu 30013, Taiwan.
authors.forename: Fu-Nien
authors.initials: FN
authors.lastname: Wang