An isocenter detection and verification device for use in proton therapy

Area of Science:

• Medical Physics
• Radiation Oncology

Background:

• Accurate isocenter alignment is critical for precise radiation delivery in proton therapy.
• Existing methods for isocenter verification can be time-consuming and complex.

Purpose of the Study:

• To develop and evaluate a novel device for comprehensive isocenter detection and verification in proton therapy settings.
• To assess the device's accuracy and efficiency compared to standard procedures.

Main Methods:

• The new device was used to verify isocenters of room lasers, digital radiography systems, and rotational gantries.
• Visual agreement was assessed for room laser and digital radiography system isocenters.
• The star-shots method with Gafchromic film and a 2 mm slitted 200 MeV proton beam was employed for rotational gantry isocenter verification.

Main Results:

• The developed device demonstrated good agreement between room laser and digital radiography system isocenters.
• Isocenter size distribution using the star-shots method was <2 mm, meeting AAPM TG-142 recommendations.
• The device significantly reduced working time to approximately 30 minutes, including preparation.

Conclusions:

• The new device provides a comprehensive solution for isocenter detection and verification across multiple proton therapy equipment.
• Implementation of this device can decrease measurement uncertainty and improve the accuracy of daily treatments.
• The device offers a time-efficient and accurate method for quality assurance in proton therapy.