A computerized remote table control for fast on-line patient repositioning: implementation and clinical feasibility

Area of Science:

• Medical Physics
• Radiation Oncology
• Medical Engineering

Background:

• Accurate patient positioning is critical in radiation therapy to ensure precise tumor targeting and minimize dose to healthy tissues.
• Online setup corrections during treatment can significantly improve treatment accuracy by compensating for patient movement and setup variations.
• The Siemens ZXT treatment couch is a key component in delivering radiation therapy, and its precise control is essential.

Purpose of the Study:

• To investigate the feasibility of a computerized remote control system for the Siemens ZXT treatment couch for online setup corrections.
• To evaluate the accuracy and speed of the treatment couch's movements in response to remote commands.
• To establish the system's suitability for real-time adjustments during radiation therapy sessions.

Main Methods:

• A computerized remote control system was implemented, communicating with the Siemens ZXT treatment couch via a serial line.
• The system was tested using "goto" commands for translations (±4 cm) and rotations (±4 degrees) in single directions and simultaneously in three dimensions.
• Accuracy was assessed by measuring deviations from target positions, and movement times were recorded for various scenarios, including simulated clinical setup errors.

Main Results:

• Single-direction movements showed high accuracy with no systematic deviations, achieving 0.6 mm (1 SD) for translations and 0.04 degrees (1 SD) for rotations.
• Simultaneous 3D movements, including rotations, resulted in a 3D vector length error of 0.96 mm (1 SD).
• Movement times were efficient, with 95% of translations completed in under 11 seconds without rotations and under 16 seconds with rotations.

Conclusions:

• The computerized remote control system for the Siemens ZXT treatment couch provides accurate and rapid movements.
• The system's performance is suitable for implementing online setup corrections in daily clinical radiation therapy practice.
• This technology enhances the precision and efficiency of radiation delivery, potentially improving patient outcomes.