In vivo dose verification of IMRT treated head and neck cancer patients.

نویسندگان

  • Per E Engström
  • Pia Haraldsson
  • Torsten Landberg
  • Hanne Sand Hansen
  • Svend Aage Engelholm
  • Håkan Nyström
چکیده

An independent in vivo dose verification procedure for IMRT treatments of head and neck cancers was developed. Results of 177 intracavitary TLD measurements from 10 patients are presented. The study includes data from 10 patients with cancer of the rhinopharynx or the thyroid treated with dynamic IMRT. Dose verification was performed by insertion of a flexible naso-oesophageal tube containing TLD rods and markers for EPID and simulator image detection. Part of the study focussed on investigating the accuracy of the TPS calculations in the presence of inhomogeneities. Phantom measurements and Monte Carlo simulations were performed for a number of geometries involving lateral electronic disequilibrium and steep density shifts. The in vivo TLD measurements correlated well with the predictions of the treatment planning system with a measured/calculated dose ratio of 1.002+/-0.051 (1 SD, N=177). The measurements were easily performed and well tolerated by the patients. We conclude that in vivo intracavitary dosimetry with TLD is suitable and accurate for dose determination in intensity-modulated beams.

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عنوان ژورنال:
  • Acta oncologica

دوره 44 6  شماره 

صفحات  -

تاریخ انتشار 2005