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On the confounding effect of temperature on chemical shift-encoded fat quantification
Diego Hernando1, Samir D Sharma, Harald Kramer
1Department of Radiology, University of Wisconsin, Madison, Wisconsin, USA.
Magnetic Resonance in Medicine
|October 15, 2013
Summary
Temperature significantly impacts chemical shift-encoded fat quantification accuracy. Uncorrected temperature variations lead to substantial errors in fat measurements, particularly with standard modeling techniques.
Area of Science:
- Medical Imaging
- Biophysics
Background:
- Proton resonance frequency of water is temperature-dependent.
- This dependency affects fat (triglyceride) quantification in chemical shift-encoded MRI (CSE-MRI).
Purpose of the Study:
- To investigate and characterize the confounding influence of temperature on CSE-MRI fat quantification.
- To evaluate the accuracy of different fat quantification methods under varying temperatures.
Main Methods:
- Simulated CSE-MRI fat-water signals at various temperatures and echo times.
- Acquired phantom and ex vivo human liver data using spectroscopy and CSE imaging across a temperature range (0-40°C).
- Performed fat-water reconstructions using magnitude and complex fitting with standard and temperature-corrected signal models.
Main Results:
- Magnitude fitting with standard signal modeling produced significant fat quantification errors, especially near specific echo times.
- Complex fitting reduced temperature-related errors.
- Temperature-corrected signal modeling successfully avoided quantification errors.
Conclusions:
- Temperature is a critical confounding factor in fat quantification using CSE-MRI.
- Failure to account for temperature can lead to substantial errors in phantom and ex vivo studies.
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