Three-dimensional magnetic resonance imaging of the upper abdomen at high spatial resolution during free breathing

MRI is a powerful, non-invasive technique for imaging soft tissues, but scans of the upper abdomen are often affected by breathing and other body motion. To reduce motion artifacts, patients are usually asked to hold their breath, which is difficult for many and limits scan quality and duration.

This thesis focuses on developing MRI methods that allow patients to breathe freely while still producing sharp, high-resolution images. By using a motion-robust radial scanning strategy and a new data-sorting approach, motion effects caused by breathing can be corrected after the scan. This results in clearer and more reliable images without increasing discomfort for the patient.

The methods were successfully applied at both standard and ultra-high magnetic field strengths, showing improved image quality and higher signal-to-noise compared to conventional MRI. Finally, these techniques were used to improve the non-invasive detection of lymph nodes in the abdomen, including after the use of specialized contrast agents.

Overall, this work demonstrates that high-quality MRI of the upper abdomen during free breathing is feasible and has strong potential to improve clinical diagnosis and disease staging.