HDR quality assurance methods for personal digital assistants

Area of Science:

• Medical Physics
• Radiotherapy
• Quality Assurance

Background:

• Clinical high-dose-rate (HDR) brachytherapy requires robust quality assurance (QA) for treatment plan verification.
• Existing QA methods can be time-consuming, necessitating efficient and reliable verification procedures.
• The AAPM TG59 report recommends independent verification of HDR brachytherapy treatment plans.

Purpose of the Study:

• To describe dosimetric methods and software for a departmental HDR brachytherapy QA program using personal digital assistants (PDAs).
• To develop a practical, user-friendly QA tool for verifying HDR treatment plans, including MammoSite applications.
• To ensure high probability of detecting significant errors in HDR treatment planning efficiently.

Main Methods:

• Developed general-purpose PDA applications for linear, planar, and volume HDR implants, estimating total dwell time.
• Incorporated modified Paterson-Parker (PP) and Greenfield-Tichman-Norman (GTN) radium tables for HDR calculations.
• Created a MammoSite-specific application using AAPM TG43 formalism and optional balloon volume dosimetry, accounting for source decay.

Main Results:

• PDA software enables effortless, general-purpose HDR QA by providing quick total dwell time verification.
• For MammoSite treatments, TG43-based calculations on PDAs are practical and equivalent to interpolating PP/GTN tables up to 5 cm.
• The software utilizes PDA features like clock/calendar for decay correction and touch screen for intuitive data entry.

Conclusions:

• PDA-based software offers an efficient and practical solution for HDR brachytherapy QA, improving accuracy and reducing verification time.
• This approach makes independent treatment plan verification accessible and effortless for HDR brachytherapy programs.
• The developed software provides a valuable tool for ensuring patient safety in HDR brachytherapy, especially for specialized applications like MammoSite.