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Differentiating supraclavicular from gluteal adipose tissue based on simultaneous PDFF and T2 * mapping using a
Daniela Franz1, Maximilian N Diefenbach1, Franziska Treibel1
1Department of Diagnostic and Interventional Radiology, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany.
Journal of Magnetic Resonance Imaging : JMRI
|January 27, 2019
Summary
Increasing MRI echoes improves adipose tissue T2* mapping precision. A 20-echo sequence enhances differentiation between white and brown fat, unlike proton density fat fraction (PDFF) quantification.
Area of Science:
- Magnetic Resonance Imaging (MRI)
- Biomedical Engineering
- Radiology
Background:
- Adipose tissue (AT) comprises white and brown/beige subtypes.
- Water-fat MRI techniques map proton density fat fraction (PDFF) and T2*.
- Brown AT exhibits lower PDFF and shorter T2* than white AT, but T2* values vary.
Purpose of the Study:
- To improve T2* measurement accuracy using an optimized experimental design.
- To investigate gluteal and supraclavicular AT T2* and PDFF using a 20-echo acquisition.
- To explore the relationship between AT T2* and PDFF.
Main Methods:
- Simulated ground truth signal evolution using a single-T2* water-fat model.
- Performed in vivo 20-echo gradient-echo MRI at 3T in 21 healthy subjects.
- Analyzed supraclavicular and gluteal AT PDFF and T2* using complex-based water-fat separation.
Main Results:
- Both PDFF and T2* significantly differed between supraclavicular and gluteal AT with 6 and 20 echoes.
- 20-echo T2* mapping showed higher precision (lower standard deviation, narrower range) than 6-echo.
- Strong correlations found between PDFF and T2* in both AT compartments (R²=0.63–0.86).
Conclusions:
- Increasing echoes beyond 6 does not impact AT PDFF quantification.
- A 20-echo acquisition significantly improves AT T2* precision.
- Multiparametric analysis with 20 echoes may enhance MR-based differentiation of AT subtypes.
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