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Treatment plan complexity metrics for predicting IMRT pre-treatment quality assurance results

  • S. B. CroweEmail author
  • T. Kairn
  • J. Kenny
  • R. T. Knight
  • B. Hill
  • C. M. Langton
  • J. V. Trapp
Scientific Paper

Abstract

The planning of IMRT treatments requires a compromise between dose conformity (complexity) and deliverability. This study investigates established and novel treatment complexity metrics for 122 IMRT beams from prostate treatment plans. The Treatment and Dose Assessor software was used to extract the necessary data from exported treatment plan files and calculate the metrics. For most of the metrics, there was strong overlap between the calculated values for plans that passed and failed their quality assurance (QA) tests. However, statistically significant variation between plans that passed and failed QA measurements was found for the established modulation index and for a novel metric describing the proportion of small apertures in each beam. The ‘small aperture score’ provided threshold values which successfully distinguished deliverable treatment plans from plans that did not pass QA, with a low false negative rate.

Keywords

Quality assurance Beam complexity Radiation therapy 

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Copyright information

© Australasian College of Physical Scientists and Engineers in Medicine 2014

Authors and Affiliations

  • S. B. Crowe
    • 1
    Email author
  • T. Kairn
    • 1
    • 2
  • J. Kenny
    • 3
  • R. T. Knight
    • 2
  • B. Hill
    • 2
  • C. M. Langton
    • 1
  • J. V. Trapp
    • 1
  1. 1.Science and Engineering FacultyQueensland University of TechnologyBrisbaneAustralia
  2. 2.Genesis Cancer Care QueenslandBrisbaneAustralia
  3. 3.Epworth Radiation OncologyMelbourneAustralia

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