Introduction: Nowadays new radiochromic films have an essential role in radiotherapy dosimetry. Properties such as high sensitivity, good reproducibility, high spatial resolution, easy readout and portability have made them attractive for dosimetry, especially in high-dose-gradient regions. Material and Methods: In this study, electron-beam dose distributions in homogenous and heterogeneous pha...

conclusions using the maximum dose depth from pdd curves and the inverse square law, the required ssdeff to calculate the dose distribution of the electron beam can be calculated. objectives the aim of this study was to determine the effective source-surface distance (ssdeff) of an electron linear accelerator (linac), and its dependence on energy and depth. materials and methods a varian linac ...

PURPOSE Historically, treatment of malignant surface lesions has been achieved with linear accelerator based electron beams or superficial x-ray beams. Recent developments in the field of brachytherapy now allow for the treatment of surface lesions with specialized conical applicators placed directly on the lesion. Applicators are available for use with high dose rate (HDR)(192)Ir sources, as w...

Electron-beam therapy is used to treat superficial tumors at a standard 100 cm source-to-surface distance (SSD). However, certain clinical situations require the use of an extended SSD. In the present study, Monte Carlo methods were used to investigate clinical electron beams, at standard and non-standard SSDs, from a Siemens Oncor Avant Garde (Siemens Healthcare, Erlangen, Germany) linear acce...

Lead or cerrobend blocking strips are used to shape electron treatment fields when an appropriate custom insert is not available. For the Varian 2100C accelerator, the structural supports of the electron applicators impede the free placement of these field-shaping strips on the open custom insert frame while placement at the top of the applicator is unimpeded. We have investigated the dosimetri...

Model-based dose calculation algorithms have recently been incorporated into brachytherapy treatment planning systems, and their introduction requires critical evaluation before clinical implementation. Here, we present an experimental evaluation of Oncentra® Brachy Advanced Collapsed-cone Engine (ACE) for a multichannel vaginal cylinder (MCVC) applicator using radiochromic film. A uniform dose...

A custom balloon applicator was created to deliver intracavitary high-dose-rate brachytherapy to a patient with a superficial vaginal cancer. The patient was unable to be treated conventionally due to an extremely narrow introitus that prevented the introduction of a conventional cylinder applicator. The custom applicator was constructed by inserting a straight titanium tandem applicator throug...

The microwave processing of wood is a widely used as high intensity microwave treatment creates changes in wood structure, which might significantly contribute to the development needs of timber industry, by accelerating wood drying time, relieving of growth stresses, facilitating preservative impregnation and enabling the production of solid wood products. Microwave wood modification requires ...

PURPOSE The potential of P-32 ophthalmic applicator irradiation after pterygium excision has been demonstrated as an alternative to Sr∕Y-90 irradiation. This study aimed to provide the clinical dosimetry for this new applicator. METHODS The prototype of a cylindrical P-32 applicator was fabricated according to the Monte Carlo (MC)-based design study. At a nominal activity of 6 mCi (0.22 GBq),...

The specific design of the mobile dedicated intraoperative radiotherapy (IORT) accelerators and different electron beam collimation system can change the dosimetric characteristics of electron beam with respect to the conventional accelerators. The aim of this study is to measure and compare the dosimetric characteristics of electron beam produced by intraoperative and conventional radiotherapy...