The dynamic nature of IMRT delivery poses unique problems relating to the accurate and reproducible quality assurance of dose delivery. The usefulness of point detectors is limited to static fields and regions within low dose-gradients for treatment verification. However, dose distributions generated in intensity modulated radiation therapy (IMRT) often have complex shapes with high dose gradie...

Introduction Dosimetric accuracy is a major issue in the quality assurance (QA) program for treatment planning systems (TPS). An important contribution to this process has been a proper dosimetry method to guarantee the accuracy of delivered dose to the tumor. In brachytherapy (BT) of gynecological (Gyn) cancer it is usual to insert a combination of tandem and ovoid applicators with a complicat...

In order to provide automatic IMRT dose delivery with an add-on MMLC a technical integration of a MMLC system with a linear accelerator was realized. The principle of this integration and the changes and enhancements of the existing hard- and software are briefly described. The system was tested by the automatic delivery of an IMRT plan designed for a head and neck phantom. A verification of do...

An integrated treatment delivery system for conformal stereotactic radiosurgery (CSRS) and radiotherapy (CSRT) has been developed through a collaboration involving Siemens Medical Systems, Inc., Tyco/Radionics, Inc., and The University of Texas M. D. Anderson Cancer Center. The system consists of a 6-MV linear accelerator (LINAC) equipped with a Tyco/Radionics miniature multileaf collimator (mM...

Helical tomotherapy is a rotational delivery technique that uses intensity-modulated fan beams to deliver highly conformal intensity-modulated radiation therapy (IMRT). The beam-on time needed to deliver a given prescribed dose can be up to 15 times longer than that needed using conventional treatment delivery. As such, there is concern that this delivery technique has the potential to increase...

at the present, many drugs are used for inhibition of uterine contractions, but the proportions of preterm labors are increasing. although magnesium sulfate is the most commonly prescribed parenteral tocolytic agent, but its optimal use has yet to be delineated. in this study a high-dose protocol for magnesium sulfate tocolytic therapy was compared with a low-dose regimen. one-hundred patients ...

introduction dosimetric accuracy is a major issue in the quality assurance (qa) program for treatment planning systems (tps). an important contribution to this process has been a proper dosimetry method to guarantee the accuracy of delivered dose to the tumor. in brachytherapy (bt) of gynecological (gyn) cancer it is usual to insert a combination of tandem and ovoid applicators with a complicat...

Introduction: Stereotactic body radiotherapy delivers hypofractionated irradiation with high dose per fraction through complex treatment techniques. The increased complexity leads to longer dose delivery times for each fraction. The purpose of this study is to investigate the impact of prolonged fraction delivery time with high-dose hypofractionation on the killing of cultured ACHN cells.Method...