MRI-compatible abdomen phantom to mimic respiratory-triggered organ movement while performing needle-based...

Area of Science:

• Biomedical Engineering
• Medical Imaging
• Materials Science

Background:

• In vivo studies for medical device validation are costly, complex, and ethically scrutinized.
• Anthropomorphic phantoms offer a solution for medical education and R&D of image-guided interventions.
• Existing phantoms may lack the necessary customization and realistic anatomical/physiological simulation.

Purpose of the Study:

• To present an MRI-compatible, customizable motion phantom for simulating respiratory-triggered organ movement and human anatomy.
• To develop a low-cost, modularizable phantom for medical education and medical device development.
• To reduce reliance on in vivo experiments in medical research.

Main Methods:

• Utilized polyvinyl alcohol cryogel (PVA-C) to create abdominal tissues (muscles, liver, kidneys, tumors) with tunable properties.
• 3D-printed a semi-flexible rib cage and developed a motion unit (MU) with a stepper motor to simulate respiration.
• Integrated components into an abdominal phantom body (APB) for MRI compatibility and motion simulation.

Main Results:

• The PVA-C based APB successfully mimicked human tissue properties (relaxation times, dielectricity, elasticity).
• The phantom demonstrated resistance to mold and resealable properties after needle punctures.
• The motion unit accurately simulated physiological organ displacement without compromising MRI quality, despite minor long-term material changes.

Conclusions:

• A novel, modular, and low-cost PVA-C based APB effectively mimics fundamental organ motion.
• Further optimization of PVA-C composition is required for enhanced long-term use and motion realism.
• This phantom provides a valuable tool for medical training and the R&D of medical devices, potentially reducing in vivo testing.