Source localization in intracavitary 60Co therapy with semiconductor and TL detectors

Area of Science:

• Medical Physics
• Oncology
• Radiotherapy

Background:

• Intracavitary brachytherapy is crucial for treating cervical cancer.
• Accurate source localization is essential for effective radiation dose delivery and minimizing side effects.
• Traditional methods like X-ray films have limitations in precise source positioning verification.

Purpose of the Study:

• To evaluate the accuracy of thermoluminescence and p-type semiconductor detectors for source localization in intracavitary brachytherapy.
• To compare detector-based localization with conventional X-ray film methods.
• To analyze the deviation patterns of intracavitary radiation sources in patients with advanced cervical cancer.

Main Methods:

• Utilized thermoluminescence and p-type semiconductor detectors for real-time source localization.
• Employed the modified Stockholm method for intracavitary treatment.
• Compared detector readings with standard X-ray film images for validation.
• Analyzed patient data from Stage III to IV carcinoma cervix uteri cases.

Main Results:

• Thermoluminescence and semiconductor detectors showed good agreement with X-ray films for source localization.
• Optimal agreement was achieved when detectors were placed bilaterally.
• Intracavitary sources exhibited symmetrical deviation probabilities to either side.
• Source deviation followed a Gaussian distribution with a mean of zero and a standard deviation of 8mm.

Conclusions:

• Thermoluminescence and p-type semiconductor detectors are reliable tools for intracavitary source localization.
• Bilateral detector placement enhances localization accuracy.
• Understanding source deviation patterns aids in optimizing treatment planning and dose delivery for cervical cancer patients.