Modular Dynamic Torso Motion Phantom for MRI

Motivation: The development of motion tracking and correction methods requires suitable motion phantoms. Goal(s): The design, fabrication, assembly and testing of a modular dynamic torso phantom. Approach: The phantom consists of a saline-filled acrylic shell, with dimensions comparable to a human torso and three distinct interior motion modules. Two linear piezo stages are used to mimic breathing motion of the chest wall and the abdominal organs including the heart, respectively. A pneumatic system is used to move a heart mock-up to represent cardiac motion. Results: The motion capabilities and MR compatibility of the phantom are validated in 3 T MRI experiments. Impact: This work presents the development of a dynamic torso phantom for MR applications, i.e. a scientific instrument that can serve as ground truth for the investigation and characterization of novel motion compensation and tracking methods.