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Updated: Aug 9, 2026

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Human Fetal Blood Flow Quantification with Magnetic Resonance Imaging and Motion Compensation
Published on: January 7, 2021
Self-supervised reconstruction framework via motion- and physics-informed learning for four-dimensional magnetic
Chenyang Liu1, Lu Wang2, Xiang Wang1
1Department of Health Technology and Informatics, The Hong Kong Polytechnic University, 999077, Hong Kong Special Administrative Region of China.
Medical Image Analysis
|August 7, 2026
Summary
A new self-supervised deep learning method, SS-4DMRF, reconstructs motion-resolved liver tissue maps faster and more accurately. This advances precision in liver cancer radiotherapy using quantitative MRI.
Area of Science:
- Medical Imaging
- Radiotherapy
- Artificial Intelligence in Medicine
Background:
- Four-dimensional magnetic resonance fingerprinting (4DMRF) offers precise, motion-resolved tissue quantification for liver cancer radiotherapy.
- Clinical adoption is limited by long reconstruction times and the lack of ground-truth 4D data for deep learning acceleration.
Purpose of the Study:
- To develop the first self-supervised reconstruction framework (SS-4DMRF) for 4DMRF, enabling motion-resolved tissue map reconstruction without supervised labels.
- To accelerate 4DMRF reconstruction time while maintaining or improving accuracy for clinical translation.
Main Methods:
- Proposed SS-4DMRF framework utilizing a temporal low-rank-constrained registration (TelReg) network for motion modeling.
- Employed self-supervision using undersampled k-space data and subspace images, leveraging respiratory motion's low-rank property.
- Implemented a physics-informed pattern matching (PiPM) network with Swin Transformers and Bloch-equation-guided denoising for motion-informed compensation and tissue quantification.
Main Results:
- SS-4DMRF demonstrated superior accuracy in tissue quantification and motion measurement compared to state-of-the-art methods on phantom and patient data.
- Achieved significantly reduced normalized root-mean-square error (NRMSE) in 4D tissue property quantification and improved inter-phase motion repeatability (p<0.001).
- Showcased a 10-fold acceleration in reconstruction time, with accurate tumor motion trajectory correlation (r=0.939±0.057).
Conclusions:
- SS-4DMRF provides rapid, precise, and motion-resolved quantitative MRI, enhancing liver cancer radiotherapy precision.
- Establishes a clinically feasible platform for accelerated abdominal quantitative MRI in oncology.
- Overcomes limitations of supervised deep learning by enabling self-supervised reconstruction from undersampled data.
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