This study explores how the metal materials of the applicator influence the dose distribution when performing brachytherapy for cervical cancer. A pinpoint ionization chamber, Monte Carlo code MCNPX, and treatment planning system are used to evaluate the dose distribution for a single Ir-192 source positioned in the tandem and ovoid. For dose distribution in water with the presence of the tande...

Introduction: Polymer gels are modern dosimeters providing three dimensional dose distributions. These dosimeters can be used in brachytherapy in which the tumor dimension is relatively small and the dose gradient is high. In this study, the ability of the MAGICA polymer gel was investigated for assessing the absolute dose values as well as the dose distribution of low dose rate (LDR) Ir-192 wi...

Source positioning close to the tumour in high dose rate (HDR) brachytherapy is not instantaneous. An increment of dose will be delivered during the movement of the source in the trajectory to its static position. This increment is the transit dose, often not taken into account in brachytherapeutic treatment planning. The transit dose depends on the prescribed dose, number of treatment fraction...

P"rpse: To investigate the clinical and histological toxicity of the exposure of the :rabbit cornea1 endothelium to anterior chamber injection of liposome-encapsulated 5-fluorouridine (LS-FUR) at concentrations of 1 mg/ml and 0.38 mg/ml and intravitreal injection of I.5FUR at 1 mg/ml. M*thOdS : A total of 12 New Zealand white rabbits were divided in three groups: A) Anterror chamber rnjectian o...

A comprehensive review for the in-air calibration of an Ir-192 high-dose-rate brachytherapy source in terms of air kerma strength (AKS) and reference air kerma rate (RAKR) using the Farmer chamber was conducted. The reviewed calibration methods include the National Physical Laboratory (NPL) calibration standard in the UK, the 7-distance technique with the standard calibration of the National In...

PURPOSE To observe the efficiency of reirradiation with high dose rate intraluminal brachytherapy in symptomatic palliation of recurrent endobronchial tumors. MATERIALS AND METHODS Between January 1994 and June 1998, 21 patients diagnosed with recurrent endobronchial tumors following external beam radiotherapy were treated palliatively with high dose rate intraluminal irradiation at Hacettepe...

The selection and use of any method to be used for radiography depends on a number of considerations, these in general being: a) The size, shape, orientation and distribution of imperfection in the weld. b) The dimensions, geometry and physical properties of the weld and material. c) The radiographic sensitivity required by the Standard, Code or Specification. d) Cost of radiography. e) The loc...

tope has recently been proposed as a hypothetical brachytherapy source due to its high specific activity, appropriate half-life (272 days) and medium energy photons (114.17 keV on average). In this study, Task Group No. 43 dosimetric parameters were calculated and reported for a hypothetical 57Co source. Material and methods: A hypothetical 57Co source was simulated in MCNPX, consisting of an a...