Real-time distortion correction of spiral and echo planar images using the gradient system impulse response function
Adrienne E Campbell-Washburn1, Hui Xue1, Robert J Lederman1
1Pulmonary and Cardiovascular Branch, Division of Intramural Research National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA.
Magnetic Resonance in Medicine
|June 27, 2015
Summary
This study introduces a real-time distortion correction framework for fast MRI imaging techniques like spiral and echo planar imaging (EPI). This advancement enables high-frame-rate MRI for interventional procedures.
Area of Science:
- Magnetic Resonance Imaging (MRI)
- Medical Imaging Technology
Background:
- Interventional MRI requires high frame rate imaging.
- Fast imaging techniques like spiral and echo planar imaging (EPI) are appealing but suffer from distortions.
Purpose of the Study:
- To implement a real-time distortion correction framework for fast MRI acquisitions.
- To enable the use of spiral and EPI imaging for MRI-guided interventions.
Main Methods:
- Utilized gradient impulse response function (GIRF) measured by standard equipment to correct distortions.
- Calculated predicted k-space trajectories at runtime using GIRF calibration file.
- Modified off-resonance reconstruction frequency in real time to deblur spiral images.
Main Results:
- Achieved real-time distortion correction for arbitrary orientations in phantoms and volunteers.
- Demonstrated close matching between GIRF-predicted and measured k-space trajectories for spiral imaging.
- Visibly improved spiral and EPI image distortion, with stable correction over time and temperature variations.
Conclusions:
- The developed framework enables high frame rate imaging methods for MRI-guided interventions.
- Real-time distortion correction enhances the utility of spiral and EPI imaging in interventional settings.
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