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Out-of-plane motion compensation in multislice spin-echo MRI
J K Riek1, A M Tekalp, W E Smith
1Eastman Kodak Co., Rochester, NY.
IEEE Transactions on Medical Imaging
|January 1, 1995
Summary
Patient motion in magnetic resonance imaging (MRI) degrades image quality. This study introduces a novel method to correct for out-of-plane motion (z-motion) artifacts and reduce blurring, enhancing MRI image resolution.
Area of Science:
- Medical Imaging
- Biophysics
- Image Processing
Background:
- Patient motion significantly degrades magnetic resonance imaging (MRI) quality.
- While in-plane motion (x-y) is studied, out-of-plane (z-motion) effects remain less understood.
- Out-of-plane motion causes artifacts and blurring in the slice-selection direction.
Purpose of the Study:
- To develop a model for out-of-plane motion in multislice MRI data.
- To correct motion artifacts and reduce slice-direction blurring.
- To improve overall MRI image resolution and quality.
Main Methods:
- Modeling the effect of rigid, translational out-of-plane motion on MR data.
- Utilizing nonlinear postprocessing via projection onto convex sets (POCS) for model inversion.
- Testing the method on simulated and real MRI data.
Main Results:
- Successful correction of out-of-plane motion artifacts.
- Reduction of blurring along the slice-selection direction.
- Demonstrated feasibility on actual clinical MRI data.
Conclusions:
- The proposed model and POCS inversion effectively address out-of-plane motion in MRI.
- This technique enhances image resolution and quality.
- The method is viable for real-world MRI applications.
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