Radio-luminescent imaging for rapid, high-resolution eye plaque loading verification

Area of Science:

• Medical Physics
• Radiation Oncology
• Ophthalmology

Background:

• Eye plaque brachytherapy is a standard treatment for intraocular cancers.
• Current quality assurance (QA) relies on visual inspection due to a lack of practical seed radioactivity measurement techniques.
• This limits personalized treatment, as uniform seed activity is typically used to prevent loading errors.

Purpose of the Study:

• To develop a rapid, cost-effective radio-luminescent imaging and dose calculation system.
• The system aims to verify seed activity distribution for differential loading in brachytherapy plaques.
• This facilitates intensity-modulated radiation therapy (IMRT) for customized cancer treatment.

Main Methods:

• A proof-of-concept system using a scintillator sheet coupled to a camera was constructed.
• Radio-luminescent signals from I-125 seeds in plaques were captured.
• Monte Carlo simulations predicted dose distributions, and gamma analysis compared measured signals to predicted doses.

Main Results:

• High gamma passing rates (3%/0.3 mm) were achieved for correct seed loadings.
• Incorrect loadings showed low passing rates, indicating the system's ability to detect errors.
• The QA process was significantly faster than current methods.

Conclusions:

• Radio-luminescent QA is effective for ensuring accurate, customized plaque loading.
• This technology supports the implementation of intensity-modulated, personalized brachytherapy.
• It enhances quality assurance for advanced radiation oncology techniques.