Radiological Physics and Technology

, Volume 8, Issue 1, pp 146–152 | Cite as

Factors affecting the chemical exchange saturation transfer of Creatine as assessed by 11.7 T MRI

  • Shigeyoshi Saito
  • Yuki Mori
  • Nobuyoshi Tanki
  • Yoshichika Yoshioka
  • Kenya Murase


Chemical exchange saturation transfer (CEST) is a new contrast enhancement approach for imaging exogenous or endogenous substances such as creatine (Cr), amide protons, and glutamate in the human body. An increase in field strength is beneficial for CEST imaging because of the increased chemical shift and longer longitudinal relaxation time (T1). In high-field magnetic resonance imaging (MRI), establishing and evaluating the CEST effect is important for optimizing the magnetization transfer (MT) saturation radio frequency (RF) pulses. In this study, the CEST effect on Cr was evaluated at different concentrations in pH phantoms by appropriately selecting MT saturation RF pulses using 11.7 T MRI. The results showed that the CEST efficiency increased gradually with increasing applied saturation RF pulse power and that it was affected by the number of saturation RF pulses and their bandwidths. However, spillover effects were observed with higher saturation RF pulse powers. In conclusion, we successfully performed in vitro Cr CEST imaging under optimized conditions of MT saturation RF pulses.


Chemical exchange saturation transfer Creatine Magnetization transfer Spillover effect 



Chemical exchange saturation transfer




Magnetic resonance imaging


Magnetic resonance spectroscopy


Magnetization transfer


Magnetization transfer ratio


Rapid acquisition with relaxation enhancement


Radio frequency


Longitudinal relaxation time


T2-weighted images



The authors would like to thank Mr. Junpei Ueda, Mr. Hisato Sasahara and Mr. Isamu Yabata (Graduate School of Medicine, Osaka University, Japan) for technical assistance. This work was partly supported by Grants-in-Aid for Scientific Research (Kakenhi, Nos. 24791299 and 24300167) by the Japan Society for the Promotion of Science (JSPS).

Conflict of interest

The authors declare that they have no conflicts of interest.


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Copyright information

© Japanese Society of Radiological Technology and Japan Society of Medical Physics 2014

Authors and Affiliations

  • Shigeyoshi Saito
    • 1
    • 2
  • Yuki Mori
    • 2
    • 3
  • Nobuyoshi Tanki
    • 4
  • Yoshichika Yoshioka
    • 2
    • 3
  • Kenya Murase
    • 1
    • 2
  1. 1.Department of Medical Physics and Engineering, Division of Medical Technology and Science, Faculty of Health Science, Graduate School of MedicineOsaka UniversitySuitaJapan
  2. 2.Center for Information and Neural Networks (CiNet)National Institute of Information and Communications Technology and Osaka UniversitySuitaJapan
  3. 3.Biofunctional Imaging Laboratory, Immol/Lunology Frontier Research Center (WPI-IFReC)Osaka UniversitySuitaJapan
  4. 4.RIKEN Center for Life Science Technologies (CLST)KobeJapan

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