Evaluation of mechanical accuracy for couch-based tracking system (CBTS)

Area of Science:

• Medical Physics
• Radiation Oncology
• Biomedical Engineering

Background:

• Accurate tumor tracking is crucial in radiation therapy to minimize damage to healthy tissues.
• Existing tracking systems face challenges with real-time motion compensation during treatment.

Purpose of the Study:

• To evaluate the mechanical accuracy and performance of an in-house-developed couch-based tracking system (CBTS).
• To assess the CBTS's suitability for clinical application in radiation therapy, specifically for tumor tracking.

Main Methods:

• The study evaluated the CBTS using sinusoidal waveforms and real patient respiratory motion data.
• Accuracy, reproducibility, and loading effects were assessed across X, Y, and Z axes.
• Root mean square (rms) error was calculated for key performance metrics.

Main Results:

• The overall delay time of the CBTS was determined to be 0.251 seconds.
• Accuracy and reproducibility in the Z-direction showed high rms errors with real patient data.
• Loading effect results were consistently within 1.0 mm across all directions.

Conclusions:

• The developed CBTS demonstrates potential for clinical use in radiation therapy.
• Further optimization is needed to improve Z-direction accuracy and reproducibility for real patient motion.
• The system's low loading effect suggests good mechanical stability.