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Updated: Mar 10, 2026
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Referenceless one-dimensional Nyquist ghost correction in multicoil single-shot spatiotemporally encoded MRI
Ying Chen1, Yupeng Liao2, Lisha Yuan1
1Center for Brain Imaging Science and Technology, Zhejiang University, Hangzhou, China.
Magnetic Resonance Imaging
|December 6, 2016
Summary
This study introduces a new method to eliminate Nyquist ghosts in single-shot spatiotemporally encoded (SPEN) MRI. The technique corrects artifacts without extra scans, improving image quality for faster MRI scans.
Area of Science:
- Magnetic Resonance Imaging (MRI)
- Medical Imaging Physics
Background:
- Single-shot echo planar imaging (EPI) offers speed but suffers from distortion artifacts.
- Nyquist ghosts, caused by echo inconsistencies, are a significant artifact in EPI and SPEN MRI.
- Single-shot spatiotemporally encoded (SPEN) MRI provides reduced distortion compared to EPI.
Purpose of the Study:
- To theoretically analyze Nyquist ghosts in single-shot SPEN MRI.
- To develop and validate a ghost correction method for SPEN MRI.
- To enable artifact-free, high-efficiency imaging using SPEN MRI.
Main Methods:
- Theoretical analysis of Nyquist ghost formation in SPEN MRI.
- Development of a 1D ghost correction scheme for SPEN MRI.
- Implementation of a multi-channel receiver coil data correction technique.
Main Results:
- A ghost-free image reconstruction method directly from even and odd echoes was developed.
- The proposed correction scheme effectively removes Nyquist ghosts without blurring image features.
- Experimental validation on simulation, in vivo rat, and human brain data confirmed the method's effectiveness.
Conclusions:
- The developed processing pipeline successfully corrects Nyquist ghosts in single-shot SPEN MRI.
- The method is robust and applicable to multi-channel coil data, enhancing image quality.
- This advancement facilitates more accurate and efficient MRI through artifact reduction in SPEN techniques.
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