Summary:
Α software tool (BrachyGuide) was developed for the automatic preparation of
the Monte Carlo (MC) input files. Subsequently, a user-oriented QA procedure
was developed for two commercially available MBDCAs, based on computational
dosimetry. The reference dose distributions were generated using MC simulation
with input files prepared using BrachyGuide. The comparison of MC and MBDCA
results was found in accordance with corresponding studies in the literature,
while the data and tools presented are freely distributed via the web. In
addition, an experimental-based QA procedure was developed using the novel
TruView™ radiochromic gel with Optical Tomography. The dosimetric test
performed for a TPS employing an MBDCA using TruView™ dosimeter and Optical
Tomography showed that the MBDCA provides improved dosimetric accuracy relative
to the TG-43 algorithm, in line with previously published data. Furthermore,
treatment plan cohorts of breast, head and neck and lip patients treated with
HDR brachytherapy were pooled. TG-43 data and corresponding MC calculations
using BrachyGuide were compared for each patient. Results showed that the TG-43
algorithm presents a generally significant, yet small, dose overestimation
relative to MC simulation which is not considered of major clinical
significance in terms of plan acceptance criteria.
Keywords:
Brachytherapy, TG43 algorithm, Monte Carlo simulation, Model-Based Dose Calculation algorithms, Commissioning assurance test
