To begin, educate the patients about the procedure's magnetic properties and risks upon their arrival. Instruct patients to remove all personal metallic items. Then orient the patient headfirst in a supine position on the 0.55T 1.5T or 3T system.
Provide hearing protection, an emergency bell, padding, and a blanket for safety and comfort. Next position a multi-channel flex coil just beneath the patient's chin to ensure optimal coil sensitivity across all lung areas, and secure the coils placement without hindering the patient's breathing. Then instruct the patient to close their eyes and mark the center of the lung with the MR laser.
After aligning the lung center at the isocenter, scan the initial localizers to establish a general orientation and conduct a transversal morphological scan to identify the tracheal bifurcation. Then anchor the first coronal slice at the tracheal bifurcation as a landmark to ensure reproducibility. Depending on the scan protocol, either capture three slices spaced at 100%of slice to slice distance, or acquire multiple slices covering the entire lung at 20%or 33%distance.
Next, retrieve the acquired phase resolved functional lung MRI images. Select the main path and click process to separate DICOM images based on slice location, and temporal sequence using header information, select either ANTsPy's sin with cross correlation metric, or Forsberg polynomial expansion with elastic and fluid regularization as the registration algorithm. The functional lung imaging maps of a 30-year-old healthy female showed a homogeneous distribution of the parenchymal values and low defect percentages, while those of a 60-year-old male COPD patient showed a heterogeneous distribution of the parenchymal values and high defect percentages.
