Computed tomography (CT) dosimetry normally uses an ionization chamber 100 mm long to estimate the computed tomography dose index (CTDI), however some reports have already indicated that small devices could replace the long ion chamber to improve quality assurance procedures in CT dosimetry. This paper presents a novel dosimetry system based in a commercial phototransistor evaluated for CT dosi...

Background: In vivo dosimetry is a method for estimation of overall error in the delivered dose to the patients at the end of radiotherapy process. In this research, two methods for target dose calculation were evaluated on midline and central axis of photon beams in in vivo dosimetry of thorax fields. Materials and Methods: Entrance and exit doses for anterior and lateral fields of thorax were...

Background: The formalism recommended by Task Group 60 (TG-60) of the American Association of Physicists in Medicine (AAPM) is applicable for β sources. Radioactive biocompatible and biodegradable 153Sm glass seed without encapsulation is a β- emitter with a short half life and delivers a high dose rate to the tumor in the millimeter range. In this work the dosimetry parameters of the ...

At the present time three most common approaches are used for planning of radionuclide therapy: administration fixed activity in radiopharmaceutical, or normalized per unit body mass surface. That may lead to significant deviations between prescribed and real absorbed doses healthy organs tissues. These associated with differences biodistribution pharmacokinetics radiopharmaceutical models pati...

The Technical Report Series 398 (TRS-398), Electron Dosimetry Working Party (EWDP), and Task Group 51 (TG 51) are the most important protocols for reference dosimetry. In case of electron beam dosimetry, these recommend using parallel-plate ionization chambers beams with R50 values below specific thresholds. However, recent papers suggested cylindrical dosimetry all energies. Here we compared d...

background: stereotactic radiosurgery is an important clinical tool for the treatment of small lesions in the brain, including benign conditions, malignant and localized metastatic tumors. a dosimetry study was performed for elekta ‘synergy s ’ as a dedicated stereotactic radiosurgery unit, capable of generating circular radiation fields with diameters of 1-5 cm at isocentre using the beam/egs4...

background: in vivo dosimetry is a method for estimation of overall error in the delivered dose to the patients at the end of radiotherapy process. in this research, two methods for target dose calculation were evaluated on midline and central axis of photon beams in in vivo dosimetry of thorax fields. materials and methods: entrance and exit doses for anterior and lateral fields of thorax were...

background: polymer gel dosimetry is still the only dosimetry method for direct measuring of threedimensional dose distributions. mri polymer gel dosimeters are tissue equivalent and can act as a phantom material. in this study the obtained isodose maps with pagat polymer gel dosimeter were compared to those calculated with egsnrs for singleshot irradiations of 8 and 18 mm collimators of gamma ...

In this paper we give an analysis of the neutron transmission through iron sphere using Monte Carlo and transport theory methods based on ENDF/B-VII.1 general purpose library. The motivation for investigation comes from a well-known deficiency in inelastic data older library evaluation (ENDF/B-V), giving concern fast flux underestimation within reactor pressure vessels. order to benchmark next-...