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Movement Retraining using Real-time Feedback of Performance
Published on: January 17, 2013
Hybrid prospective and retrospective head motion correction to mitigate cross-calibration errors
Murat Aksoy1, Christoph Forman, Matus Straka
1Department of Radiology, Stanford University, Stanford, California 94305-5488, USA. maksoy@stanford.edu
Magnetic Resonance in Medicine
|August 10, 2011
Summary
This study introduces hybrid prospective and retrospective MRI motion correction. This method improves image quality despite calibration errors, reducing the need for precise cross-calibration.
Area of Science:
- Medical Imaging
- Magnetic Resonance Imaging (MRI)
Background:
- External motion tracking devices offer emerging solutions for head motion correction in MRI.
- Cross-calibration between external trackers and MRI scanners presents a significant practical challenge.
Purpose of the Study:
- To present hybrid prospective and retrospective methods for head motion correction in MRI.
- To evaluate the effectiveness of these methods in the presence of cross-calibration errors.
Main Methods:
- Developed two hybrid methods combining optical-based prospective motion correction with retrospective entropy-based autofocusing.
- Investigated the impact of cross-calibration errors on image quality.
Main Results:
- Hybrid correction significantly improved image quality even with cross-calibration errors.
- The need for high-quality calibration scans was substantially reduced.
- External prospective motion tracking became feasible with only crude cross-calibration approximations.
Conclusions:
- Hybrid prospective and retrospective motion correction offers a robust solution for MRI.
- This approach relaxes stringent calibration requirements, enhancing practical applicability.
- The motion tracking system also benefits the retrospective autofocusing component.
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