Design and manufacturing of a dynamically deformable liver phantom for radiotherapy

Area of Science:

• Medical Imaging and Radiation Therapy
• Biomedical Engineering
• Phantom Development

Background:

• Accurate anatomical deformation simulation is crucial for advancing dynamic radiotherapy techniques.
• Existing phantoms often lack the ability to replicate patient-specific respiratory motion.
• Developing realistic phantoms is essential for improving treatment precision and patient outcomes.

Purpose of the Study:

• To create a novel deformable liver phantom (DELP) capable of simulating human respiratory motion.
• To enable synchronized and repeatable motion modeling for dynamic treatment investigations.
• To evaluate the performance of the DELP in radiotherapy applications.

Main Methods:

• Fabrication of an artificial silicone liver within a mold.
• Integration of a stepper motor for controlled inferior compression simulating respiratory motion.
• Inclusion of reference markers (fiducials) for movement verification and deformation calculation.
• Dynamic deformation testing with varying amplitude movements (5 mm and 10 mm).

Main Results:

• The DELP successfully simulated synchronized and repeatable respiratory motion.
• The greatest deformation occurred in the edge regions of the silicone liver.
• Average deformation measured 3.45 ± 0.93 mm at 5 mm amplitude and 5.98 ± 0.01 mm at 10 mm amplitude.
• Dosimetric equipment confirmed the phantom's suitability for radiotherapy evaluation.

Conclusions:

• The dynamically DEformable Liver Phantom (DELP) provides a reproducible method for simulating liver respiratory motion.
• The phantom's design allows for human-specific respiratory modeling, enhancing dynamic treatment research.
• DELP demonstrates potential for improving radiotherapy accuracy and efficacy through realistic motion simulation.