Three-dimensional Time-of-flight MRA Imaging

Three-dimensional time-of-flight MRA imaging was performed using a 1.5 T MRI unit (Vantage Orian; Canon Medical Systems). The imaging parameters for obtaining the MRA images were as follows: repetition time, 21 ms; echo time, 6.8 ms; flip angle, 20 degrees; number of averages, 1; field of view, 200 × 200 mm; acquisition matrix, 384 × 208; pixel bandwidth, 122 Hz; pixel size, 0.2604 mm; slice thickness, 1.1 mm; slice interval, 0.55 mm; parallel reduction factor, 3; and receive coil, Atlas Head Neck (16 channel). MRA source images were reconstructed with and without the DLR technique (Advanced Intelligent Clear IQ Engine; Canon Medical Systems) (DLR images and non-DLR images, respectively) [18 (link)].
All the MRA source images were anonymized and exported from the picture archiving and communication system in Digital Imaging and Communications in Medicine format. Maximum intensity projection (MIP) images with coronal and axial views were generated using ImageJ software (https://imagej.nih.gov/ij/) from the source MRA images.