Table of Contents
ISRN Oncology
Volume 2014, Article ID 901436, 5 pages
Research Article

Comparative Study between Measurement Data and Treatment Planning System (TPS) in Small Fields for High Energy Photon Beams

1Radiation Oncology Department, Faculty of Medicine, Al Azhar University, Egypt
2Biophysics Branch, Physics Department, Faculty of Sciences (Girls), Al Azhar University, Egypt
3National Cancer Institute (NCI), Cairo University, Egypt

Received 11 January 2014; Accepted 18 February 2014; Published 6 May 2014

Academic Editors: R.-J. Bensadoun and O. Hansen

Copyright © 2014 Khaled El Shahat et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


To achieve tumor control for radiotherapy, a dose distribution is planned which has a good chance of sterilizing all cancer cells without causing unacceptable normal tissue complications. The aim of the present study was to achieve an accurate calculation of dose for small field dimensions and perform this by evaluating the accuracy of planning system calculation. This will be compared with real measurement of dose for the same small field dimensions using different detectors. Practical work was performed in two steps: (i) determination of the physical factors required for dose estimation measured by three ionization chambers and calculated by treatment planning system (TPS) based on the latest technical report series (IAEATRS-398) and (ii) comparison of the calculated and measured data. Our data analysis for small field is irradiated by photon energy matched with the data obtained from the ionization chambers and the treatment planning system. Radiographic films were used as an additional detector for the obtained data and showed matching with TPS calculation. It can be concluded that studied small field dimensions were averaged 6% and 4% for 6 MV and 15 MV, respectively. Radiographic film measurements showed a variation in results within ±2% than TPS calculation.