Rosie Goodburn1, Tom Bruijnen2, Wajiha Bano1, Uwe Oelfke1, and Andreas Wetscherek1
1Radiotherapy and Imaging, The Institute of Cancer Research, London, United Kingdom, 2Department of Radiotherapy, University Medical Center Utrecht, Utrecht, Netherlands
1Radiotherapy and Imaging, The Institute of Cancer Research, London, United Kingdom, 2Department of Radiotherapy, University Medical Center Utrecht, Utrecht, Netherlands
UTE images acquired on an MR Linac using a multi-echo stack-of-stars sequence showed higher image quality when offline reconstruction was based on k-space trajectories that were corrected with gradient delays and measured GIRFs.
Figure 4: Phantom UTE images reconstructed with GIRF/delay correction a) off/off; b) off/on; c) on/off; d) on/on. Note artifacts: halo (solid arrows), dark boundaries (dotted arrows), and bright boundaries (dashed arrows).
Figure 3: First-order GIRFs in frequency space measured for the MR-Linac at our institution. Represented in terms of magnitude (arbitrary units) and complex phase components for physical X, Y, and Z gradients of the system.