An open-source motion platform that replicates time synchronised internal and external patient motion for real-time...

Area of Science:

• Medical Physics
• Radiotherapy Technology
• Quality Assurance

Background:

• Real-time Image-guided Radiotherapy (IGRT) requires precise tracking of intra-fractional tumor motion.
• Robust quality assurance (QA) devices are essential for the clinical implementation of real-time IGRT.

Purpose of the Study:

• To develop and characterize a novel time-synchronized motion platform for QA of real-time IGRT systems.
• To create a device capable of monitoring combined internal and external patient motion.

Main Methods:

• Development of the Internal-External Robotic Actuator (IntERAct) QA device.
• Integration of a 6-degree-of-freedom (6DoF) robotic arm for internal motion and a 1-degree-of-freedom (1DoF) actuator for external motion.
• Validation using patient-measured lung and liver motion traces.

Main Results:

• The IntERAct device successfully replicated internal and external motion.
• Synchronization of internal and external motions achieved within 0.1 seconds.
• Geometric accuracy under two millimeters demonstrated.

Conclusions:

• The IntERAct device provides a robust and repeatable solution for QA of real-time IGRT.
• The open-source availability of the device facilitates its adoption by the medical physics community.
• This QA platform supports the safe and effective clinical use of advanced radiotherapy techniques.