Monte Carlo simulation of wax compensating filters for radiotherapy of the head and neck

  • E. Spezi
  • D. G. Lewis
  • K. Gray
  • C. W. Smith
Conference paper


The use of individualised compensating filters has long been established in radiotherapy to modify dose distributions to allow for contour and tissue variations [1]. Compensators are designed to replace the missing tissue required to produce a uniform patient surface but are retracted away from the skin in order to preserve the skin-sparing effect in megavoltage photon beams. Compensators, made from tissue-equivalent or from higher density materials, are commonly used for radiotherapy of the head and neck. The dose to the patient can be calculated by modelling measured data for the reduction in dose due to loss of scattered radiation from the missing tissue [2] [3]. However the anatomical complexity of the treatment region and the tissue inhomogeneities present requires an accurate calculation of the effects of scattered radiation and electron contamination produced when modelling the thickness of compensator material required [4] [5]. Moreover there is a clinical need to etablish more firmly 3D dose distribution in patient arising by using wax compensators [6], for a better evaluation of Intensity Modulated Radiation Therapy benefits.


Depth Dose Monte Carlo Code Percentage Depth Dose Retraction Factor Monte Carlo Dose Calculation 
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Copyright information

© Springer-Verlag Berlin Heidelberg 2000

Authors and Affiliations

  • E. Spezi
    • 1
  • D. G. Lewis
    • 1
  • K. Gray
    • 1
  • C. W. Smith
    • 1
  1. 1.Department of Medical PhysicsVelindre HospitalCardiffUK

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