الفهرس 
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Abstract
In Mansoura University Hospitals, a well-selected patients suffering from malignant bone twnors were treated by intraoperative extracorporeal irradiation and reimplantation of autogenous bone grafts (ECI). The intraoperative electron beam therapy (IOERT) with lyon intraoperative system was used to treat patients with muscle-invasive cancer bladder.
The aim of thiS study was to investigate the main dosimetric characteristics of these techniques and to develop a suitable Q A program for them. In this study the dosimetry procedures of ECl and IOERT techniques were reported for bone twnor and cancer bladder under specific geometry conditions, by using the energy of 6 MV photon beam and 15 MeV electron beam.
different dosimetric measurements of 6 MV photon beam and 15 MeV beam from Elekta SI-15 linear accelerator were perfonned in MP3-S water photon (PTW) with Markus, dual 0.125 and 0.6 cm3 ion chambers. First group of ECI bone twnor specimens were irradiated at shortened source-to-center of tumor distance (= 65 cm) to obtain a high dose rate and to reduce the irradiation time of a high prescribed dose (300 Gy). Second group were treated at normal source-to-center of tumor distance (= 100 cm) and normal prescribed dose of 50 Gy.
The measuted central axis percent depth dose (PDD) data of all conventional applicators reveals that, the depth of maximwn dose (dm), the depth of 90% and 50% (R90and R50) were increased with increasing the applicator size from 6x6 to lOx10cm2 and there was no significant change in these parameters for the larger applicators (> 1Ox10 cm2 applicator). It was found that, the surface dose (Ds) of the applicators 6x6 was higher than that of all other applicators. The width and depth of 95% isodose line was found to be increased with increasing in the applicator size.
The measured output factors for a set of conventional applicators were found to be doing not vary smoothly with the applicator size