Patient setup and verification for intensity-modulated radiation therapy (IMRT)

Area of Science:

• Radiation Oncology
• Medical Physics

Background:

• Intensity Modulated Radiation Therapy (IMRT) is a widely adopted technique in radiation oncology.
• IMRT enables complex dose distributions, facilitating dose escalation to tumors while sparing surrounding normal tissues.
• The implementation of IMRT necessitates changes in the roles and workflows of physicists, dosimetrists, and physicians.

Purpose of the Study:

• To describe a standardized Intensity Modulated Radiation Therapy (IMRT) process from simulation through planning and treatment delivery.
• To highlight the importance of quality assurance (QA) procedures in IMRT.
• To provide insights into overcoming common challenges in IMRT planning and delivery.

Main Methods:

• Standardization of simulation procedures to decrease setup times and collision risks.
• Utilizing pseudo-DRRs and multiple-exposure port films for patient positioning verification.
• Implementing a treatment delivery QA program with film and MOSFET detectors in a phantom.

Main Results:

• Standardized simulations led to reduced setup times and fewer collisions.
• Established methods for confirming patient positioning accuracy on the linear accelerator.
• Developed a robust QA program for verifying treatment delivery accuracy.

Conclusions:

• A standardized IMRT process, incorporating rigorous QA, is crucial for safe and accurate treatment delivery.
• Addressing common issues like isocenter location, collision avoidance, and dose confirmation is essential for successful IMRT implementation.
• The described process provides a framework for other institutions to adopt and adapt for their IMRT programs.