A Comparison of the Distortion in the Same Field MRI and MR-Linac System With a 3D Printed Phantom.

Purpose: A 3D printed geometric phantom was developed that can be scanned with computed tomography (CT) and magnetic resonance imaging (MRI) to measure the geometric distortion and determine the relevant dose changes.

Materials And Methods: A self-designed 3D printed photosensitive resin phantom was used, which adopts grid-like structures and has 822 1 cm squares. The scanning plan was delivered by three MRI scanners: the Elekta Unity MR-Linac 1.

BOLD signal simulation and fMRI quality control base on an active phantom: a preliminary study.

Blood-oxygen-level-dependent (BOLD) signal has been commonly used in functional magnetic resonance imaging (fMRI) to observe the activity in different areas of the brain or other organs. This signal is difficult to simulate, because its amplitude is nearly 1~3% and it is influenced by multiple factors. This study aimed to design and construct an active BOLD simulation phantom and test its stability and repeatability.