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Chemical exchange saturation transfer effect in blood
Shaokuan Zheng1, Imramsjah M J van der Bom, Zhongliang Zu
1Department of Radiology, UMASS Medical School, Worcester, Massachusetts, USA.
Magnetic Resonance in Medicine
|May 11, 2013
Summary
Blood can be used as a Chemical Exchange Saturation Transfer (CEST) agent for medical imaging. This study demonstrates its feasibility in vivo, showing clear contrast against surrounding tissues.
Area of Science:
- Biomedical Imaging
- Magnetic Resonance Imaging (MRI)
- Chemical Exchange Saturation Transfer (CEST)
Background:
- Chemical Exchange Saturation Transfer (CEST) is a sensitive MRI technique.
- Developing novel contrast agents is crucial for advanced medical imaging.
- Blood's potential as an endogenous CEST agent requires investigation.
Purpose of the Study:
- To investigate the feasibility of using blood as a Chemical Exchange Saturation Transfer (CEST) agent.
- To evaluate the CEST effect of blood ex vivo and in vivo.
- To establish proof-of-concept for in vivo blood imaging using CEST.
Main Methods:
- CEST effect of porcine blood was analyzed using 3.0 T MRI and 14.1 T NMR.
- In vivo experiments were conducted on healthy volunteers.
- CEST imaging was applied to the femoral artery and the M1 segment of the middle cerebral artery.
Main Results:
- Maximum CEST Magnetization Transfer Ratio asymmetry (MTRasym) values of approximately 12% were observed in blood samples.
- CEST signal from blood in vivo was significantly higher than surrounding muscular (2%) and brain tissue (3%).
- Multiple blood components likely contribute to the observed CEST effect.
Conclusions:
- Blood serves as a viable endogenous CEST agent.
- Sufficient CEST contrast is generated by blood relative to surrounding tissues.
- CEST imaging holds promise for visualizing blood in vivo.
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