Virtual 3D surface imaging system for the validation of tumor tracking algorithm used in surface-guided radiotherapy

Area of Science:

• Medical Physics
• Computer Simulation
• Radiotherapy Technology

Background:

• Surface-Guided Radiotherapy (SGRT) requires accurate tumor tracking.
• Developing SGRT algorithms often relies on idealized surface imaging data.
• Real-world 3D surface reconstruction can be costly and time-consuming.

Purpose of the Study:

• To develop a novel 3D surface reconstruction simulation system.
• The system integrates Phase Measurement Profilometry (PMP) with the Unity physics engine.
• To validate its feasibility for assisting Surface-Guided Radiotherapy (SGRT) tumor tracking algorithm development.

Main Methods:

• Structured-light-based 3D reconstruction simulation using PMP within Unity.
• Investigated parameter influences (distance, angle, light intensity) on reconstruction.
• Validated simulation by comparing real-world and virtual surface imaging of a torso model.

Main Results:

• Simulation results for light intensity and object positioning align with real-world studies.
• Sub-millimeter accuracy (RMSE 0.46-0.52 mm) achieved in surface imaging point clouds.
• Simulation system supports SGRT algorithm development, avoiding over-idealized surface data.

Conclusions:

• A cost-effective PMP-based simulation system using Unity is proposed for 3D surface reconstruction.
• The system allows diverse measurement condition simulations in a virtual environment.
• It effectively supports SGRT tumor tracking algorithm validation and advancement.