UCLA researchers have developed a subject-specific, deformable lung phantom that mimics both the mechanical (elastic) and radiological (attenuation) properties of a real human lung. The phantom is designed to replicate lung deformation during respiration, integrate imaging and computational fluid dynamics (CFD) data, and be used in radiotherapy quality assurance to improve treatment planning and patient outcomes.
For radiation therapy, accurately modeling how the lung and tumor move during breathing is critical to minimize radiation delivered to healthy tissue while ensuring the target receives the intended dose. Existing phantoms either approximate lung deformation poorly, lack accurate radiological properties (i.e. how they absorb/attenuate radiation), or are not tailored to specific patients. Also, imaging‐based deformation models (from CT or 4D‐CT) often lack validation and cannot always capture realistic mechanical behavior. There is a need for tools that more faithfully simulate patient-specific lung mechanics and radiological response for better QA of radiotherapy.
This invention combines:
A material system comprising polymer nanocomposites embedding nanoparticles to achieve both lung-like elasticity and proper radiation attenuation.
Use of imaging data (4D CT scans) from individual patients to reconstruct 3D lung geometry.
Computational fluid dynamics (CFD) and flow–structure interaction (FSI) models to simulate spatio‐temporal lung deformation during breathing.
A mathematical data fusion approach (using Tikhonov regularization) that fuses imaging (inverse estimation) data with CFD predictions to optimize and validate deformation models for specific lung anatomy.
Fabrication of a physical lung phantom (including subject-specific elastic and radiological properties) that deforms in response to airflow or respiratory motion and behaves in imaging and radiation delivery consistent with modeled predictions.
Custom, subject‐specific lung phantom that better matches patient lung geometry and elasticity.
Dual fidelity: both mechanical deformation and radiological attenuation properties are realistic.
Enables more accurate QA for radiotherapy planning and delivery, especially under motion (breathing)
Improves trust in deformation models by incorporating CFD and imaging fusion.
Allows testing and validation of radiotherapy plans, equipment, and delivery methods under realistic deforming conditions.
Radiotherapy planning and quality assurance for lung cancer patients, especially those with high respiratory motion.
Validation of dose calculation algorithms that account for breathing motion or deformation.
Development and testing of motion compensation strategies (e.g., gating, tracking).
Use in training and calibration of imaging/radiotherapy devices.
Research into lung mechanics, respiratory motion, and deformable image registration.
US 10,290,233 B2 — Physical Deformable Lung Phantom with Subject-Specific Elasticity Google Patents