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Quality Assurance

Chapter

Abstract

Treatment planning systems are computer software trying to predict the real dose absorbed by the patient using experimental data. Technologic progress in recent years has made it possible to obtain planning techniques for high-dose gradients by using inverse planning techniques. Obtained doses from three dimensional conformal radiotherapy (3D-CRT) can be validated by calculation of doses at different points. However, more knowledge and skill are expected from intensity modulated radiotherapy (IMRT) planning systems. Unlike the 3D-CRT, the IMRT field is made of many small, asymmetrical and irregular subfields. Subfields correctively obtained as a result of leaf positions are more important than in 3D-CRT. As subfields are created with multileaf collimators, naturally, accuracy of the multileaf collimator becomes more important. Multileaf collimator positioning error in IMRT causes worse results than in 3D-CRT. Furthermore, leaf transmission, output linearity, and similar data affect IMRT results much more than 3D-CRT results. Therefore, medical physicists must check the reality of results predicted by the planning system and each clinic must have its own specific quality assurance (QA) procedure [1].

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Copyright information

© Springer Science+Business Media New York 2013

Authors and Affiliations

  1. 1.Department of Radiation OncologyNear East UniversityNicosiaCyprus
  2. 2.Department of Radiation OncologyHacettepe UniversityAnkaraTurkey

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