Free-breathing pediatric MRI with nonrigid motion correction and acceleration

Area of Science:

• Medical Imaging
• Magnetic Resonance Imaging (MRI)
• Pediatric Radiology

Background:

• High-resolution abdominal MRI in children is challenging due to respiratory motion.
• Free-breathing acquisitions improve patient comfort but often suffer from motion artifacts.
• Efficient motion correction is crucial for diagnostic image quality in pediatric populations.

Purpose of the Study:

• To develop and evaluate novel motion correction techniques for free-breathing, high-resolution pediatric abdominal volumetric MRI.
• To enhance scan efficiency while maintaining diagnostic image quality.

Main Methods:

• Incorporated variable-density sampling and radial-like phase-encode ordering in 3D Cartesian acquisition.
• Utilized intrinsic multichannel butterfly navigators for respiratory motion estimation.
• Applied motion estimates for data-consistency reconstruction and nonrigid motion correction.

Main Results:

• Significantly improved overall image quality (mean score 4.7/5) compared to no correction (3.4/5) and motion-weighted accelerated imaging (3.9/5).
• Achieved comparable image quality to conventional prospective triggered acquisitions (4.5/5) with a substantially reduced scan time (28s vs. 91s).

Conclusions:

• The proposed motion correction methods enable diagnosable, high-resolution abdominal volumetric MRI in free-breathing pediatric patients.
• This advancement offers a more efficient and effective approach to pediatric abdominal imaging.