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Updated: Oct 28, 2025
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Quantitative Magnetic Resonance Imaging of Skeletal Muscle Disease
Published on: December 18, 2016
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Multiple-echo steady-state (MESS): Extending DESS for joint T2 mapping and chemical-shift corrected water-fat
Frank Zijlstra1,2, Peter R Seevinck1,3
1Image Sciences Institute, University Medical Center Utrecht, Utrecht, The Netherlands.
Magnetic Resonance in Medicine
|July 16, 2021
Summary
The multiple-echo steady-state (MESS) sequence enables robust water-fat separation comparable to existing methods, without increasing scan time. This advanced MRI technique offers a promising alternative for improved imaging.
Area of Science:
- Magnetic Resonance Imaging (MRI)
- Medical Physics
- Biomedical Engineering
Background:
- Double echo steady-state (DESS) sequences are widely used in MRI.
- Accurate water-fat separation is crucial for quantitative MRI analysis.
- Existing methods often require water-selective excitation, increasing scan time or complexity.
Purpose of the Study:
- To extend the DESS sequence for chemical-shift corrected water-fat separation.
- To introduce the multiple-echo steady-state (MESS) sequence.
- To evaluate MESS performance against water-selective DESS for cartilage imaging.
Main Methods:
- Developed the MESS sequence with modified readouts and bipolar gradients.
- Utilized an iterative fitting approach for joint water-fat separation and T2 estimation.
- Acquired MESS and water-selective DESS images in five volunteers for comparison.
Main Results:
- MESS achieved robust water-fat separation comparable in quality to water-selective DESS.
- T2 estimation with MESS was similar to DESS, with slightly increased variability.
- Signal-to-noise ratio (SNR) in MESS was comparable to DESS, despite local variations.
Conclusions:
- MESS provides effective water-fat separation within the same acquisition time as DESS.
- MESS offers comparable SNR in reconstructed water and fat images.
- MESS presents a promising alternative to DESS, providing additional image contrasts.
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