In this study we investigate the effect of detector size in the dosimetry of small fields and steep dose gradients with a particular emphasis on IMRT measurements. Comparisons of calculated and measured cross-profiles and absolute dose values of IMRT treatment plans are presented. As a consequence of the finite size of the detector that was used for the commissioning of the IMRT tool, local dis...

Proven conventional dosimetry techniques do not provide accuracy and precision in the measurement of inverse planned intensity modulated radiation therapy (IMRT) fields. Dynamic and step-and-shoot multileaf collimation (DMLC/SMLC) challenge current ionization chamber dosimetry practices. Ionization chamber performance in these fields is evaluated for three cylindrical chambers of varying volume...

The purpose of this work was to perform a comprehensive comparison of static field intensity modulated radiation therapy (IMRT) for patient specific quality assurance (QA) in order to investigate commissioning of a XiO treatment planning system (TPS). QA measurements were evaluated for three of four test geometries provided in American Association of Physicists in Medicine (AAPM) Task Group Rep...

introduction intensity-modulated radiotherapy (imrt) is becoming an increasingly routine treatment method. imrt can be delivered by use of conventional multileaf collimators (mlcs) and/or physical compensators. one of the most important factors in selecting an appropriate imrt technique is integral dose. integral dose is equal to the mean energy deposited in the total irradiated volume of the p...

background: to analyze the dosimetric and radio biologic advantages between intensity modulated radiotherapy (imrt) and 3 dimensional conformal radiotherapy (3dcrt) and selection of optimal photon energy for imrt treatments. material and methods: 24 patients with localized prostate carcinoma were planned for 3dcrt and imrt techniques. radiation dose of 54 gy with 2 gy/fraction, was planned to p...

background: external beam radiotherapy (ebrt) is mainstay of treatment in patients with locally advanced cervical carcinoma (lacc). three dimensional conformal radiotherapy (3dcrt) and intensity modulated radiotherapy (imrt) are mainly used in ebrt. however which one is superior is still controversial. materials and methods: forty patients of lacc treated with imrt were selected for this study....

Background: We have validated the monitor unit calculations from a commercially available treatment planning system (TPS) for three intensity modulated radiotherapy (IMRT) planning techniques for tangential breast irradiation by using ionization chamber measurements. Materials and Methods: Treatment plans were generated for forty-two breast patients by a forward planned field in field ...

background: 3dcrt (three-dimensional conformal radiotherapy) and imrt (intensity-modulated radiotherapy) has provided us with tools to delineate the radiation dose distribution of tumor targets. however, the precision of radiation can be compromised by respiratory motion, which usually limits the geometric and dosimetric accuracy of radiotherapy. the purpose of this study is to evaluate the imp...

background: identify the optimal technique of radiotherapy for patients with high grade glioma. our initial year of experience with rapidarc radiation therapy. materials and methods: planning ct scans of 50 patients with grade iv glioma were reviewed and three plan sets by 3d conformal radiotherapy (3dcrt), intensity modulated radiotherapy (imrt) and rapid arc (ra) were generated and the plans ...

background: we have validated the monitor unit calculations from a commercially available treatment planning system (tps) for three intensity modulated radiotherapy (imrt) planning techniques for tangential breast irradiation by using ionization chamber measurements. materials and methods: treatment plans were generated for forty-two breast patients by a forward planned field in field technique...