Development of a Deformable 3D-Printed Thorax Phantom for Workflow Simulation In CBCT-Guided Bronchoscopy
Abstract
Purpose
Cone-beam CT (CBCT) guided bronchoscopy enables precise navigation and sampling of suspicious pulmonary nodules but can be associated with a steep learning curve that limits definitive diagnosis. Existing commercial phantoms are predominantly static and lack deformable, realistic airway-lung mechanics, limiting their utility for CBCT protocol development and procedural training under motion. This work aims to develop and evaluate a programmable and deformable, anthropomorphic thorax phantom to enable realistic CBCT-guided bronchoscopy workflow simulation.
Methods
An anthropomorphic thorax phantom was fabricated featuring a rigid spine, ribcage, deformable foam lungs, and 3D-printed airways. The airway system was specifically designed to realistically integrate a bronchoscope and biopsy needle. Respiratory mechanics were simulated using a programmable motion stage inducing a reproducible 14 mm craniocaudal diaphragm displacement. The phantom was assessed by two experienced interventional pulmonologists. Assessment utilised a structured questionnaire evaluating four specific domains (Face Validity, Navigation, Usability, and Training Value) on a 5-point Likert scale, alongside Global Ratings for Realism and Training Usefulness on a 10-point scale.
Results
Fluoroscopic assessment confirmed that the programmable diaphragm motion induced repeatable airway deformation and realistic bronchoscope interaction. The pulmonologists reported mean Global Ratings of 8.0/10 for Realism and 9.0/10 for Training Usefulness. Mean domain scores demonstrated high Training Value (4.33/5) and Navigation (4.0/5), indicating effective reproduction of procedural challenges encountered during CBCT-guided bronchoscopy. Usability (4.0/5) and Face Validity (3.1/5) scores identified material limitations, primarily excessive airway wall stiffness, highlighting opportunities for further material optimization.
Conclusion
We have demonstrated the feasibility of a novel, deformable 3D-printed thorax phantom that simulates respiratory motion during CBCT-guided bronchoscopy. This approach provides realistic workflow and navigation challenges across different operator experience levels while maintaining reproducible imaging conditions. Future work will optimise material properties, specifically focusing on airway wall compliance and thickness, to facilitate realistic needle puncture and biopsy interaction.