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Temperature mapping using the water proton chemical shift: self-referenced method with echo-planar spectroscopic
K Kuroda1, R V Mulkern, K Oshio
1Research Institute of Science and Technology, Tokai University, Hiratsuka, Kanagawa, Japan. kagayaki@ridt.u-tokai.ac.jp
Magnetic Resonance in Medicine
|February 19, 2000
Summary
A new echo-planar spectroscopic imaging method offers faster temperature mapping than 3D-MRSI. This technique uses internal references, like tissue lipid, to accurately visualize temperature changes and reduce motion artifacts.
Area of Science:
- Biomedical Imaging
- Magnetic Resonance Imaging
- Spectroscopy
Background:
- Accurate temperature mapping is crucial for various medical applications.
- Conventional methods like 3D-MRSI are time-consuming.
- Phase mapping methods often require image subtractions and are sensitive to motion.
Purpose of the Study:
- To introduce a novel echo-planar spectroscopic imaging method for rapid and accurate temperature mapping.
- To overcome limitations of existing MRSI and phase mapping techniques.
- To validate the method using an internal reference for temperature error reduction.
Main Methods:
- Developed an echo-planar spectroscopic imaging sequence for temperature mapping.
- Utilized tissue lipid as an internal reference for water proton chemical shift measurement.
- Compared the proposed method with conventional phase mapping regarding speed and motion artifact reduction.
- Applied the method to a porcine liver sample for in vitro temperature visualization.
Main Results:
- The echo-planar spectroscopic imaging method demonstrated significantly faster acquisition times compared to 3D-MRSI.
- Temperature changes in the porcine liver sample were clearly visualized using the internal reference.
- The proposed method showed reduced temperature errors caused by translational motion compared to phase mapping.
- Image subtractions were not required when an internal reference was detectable.
Conclusions:
- The internally referenced echo-planar spectroscopic imaging method is a faster and more robust alternative for temperature mapping.
- This technique offers improved accuracy by minimizing temperature errors from motion artifacts.
- The use of endogenous tissue components as internal references enhances practical applicability in biological tissues.
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