Purpose (extract): “To clinically implement an MRI-only planning (MROP) workflow for both X-ray and MRI-guided systems.”
Methods (extract): “MROP implementation involved optimizing MRI simulation protocols developing a deep learning-based sCT generation method, and automating fiducial marker detection. A multichannel CycleGAN model was trained using T1-weighted Dixon images to generate sCT. For SBRT cases, the immobilization device was auto-inserted into sCT images. Fiducial markers were detected using a quantitative susceptibility mapping (QSM) method.”
“Detection efficiency and location accuracy were tested in a cohort of 22 patients, each with three gold FMs of∼0.3 mm diameter (Gold Anchor™, Naslund Medical AB) implanted in the prostate prior to MRI/CT simulation.”
Results (extract): “The QSM-based fiducial detection achieved a 95.5% success rate (63/66 markers) and reduced detection time from∼10 to 2 min per patient.”
“The 3 FMs not detected were at the very edge of the prostate.”
Conclusion:(extract): “We successfully implemented an MROP workflow for prostate cancer EBRT, eliminating the need for CT, reducing radiation exposure, and improving clinical efficiency. Over 500 patients have been treated to date using this approach on both C-arm and MR-guided systems.”