A new workflow of the on-line 1.5-T MR-guided adaptive radiation therapy.

Purpose: The aim of this study was to develop a new workflow for 1.5-T magnetic resonance (MR)-guided on-line adaptive radiation therapy (MRgART) and assess its feasibility in achieving dose constraints.

Materials And Methods: We retrospectively evaluated the clinical data of patients who underwent on-line adaptive radiation therapy using a 1.

Delivery accuracy of VMAT on two beam-matched linacs provided by accelerated go live service.

Introduction: Dosimetric accuracy is critical when a patient treated with volumetric modulated arc therapy (VMAT) is transferred to another beam-matched linac. To evaluate the performance of Accelerated Go Live (AGL) service, the measured beam characteristics and patient specific quality assurance (QA) results between two AGL-matched linacs were compared.

Materials And Methods: Two VersaHD linacs were installed using the AGL service.

Independent assessment of source position for gynecological applicator in high-dose-rate brachytherapy.

Purpose: The aim of this study is to describe a phantom designed for independent examination of a source position in brachytherapy that is suitable for inclusion in an external auditing program.

Material And Methods: We developed a phantom that has a special design and a simple mechanism, capable of firmly fixing a radiochromic film and tandem-ovoid applicators to assess discrepancies in source positions between the measurements and treatment planning system (TPS). Three tests were conducted: 1) reproducibility of the source positions ( = 5); 2) source movements inside the applicator tube; 3) changing source position by changing curvature of the transfer tubes.

Initial experience of radiotherapy plus cetuximab for Japanese head and neck cancer patients.

In Japan, cetuximab with concurrent bioradiotherapy (BRT) for squamous cell carcinoma of head and neck (SCCHN) was approved in December 2012. We herein report our initial experience of BRT, with special emphasis on acute toxicities of this combination therapy. Thirty-one non-metastatic SCCHN patients who underwent BRT using cetuximab between July 2013 and June 2014 were retrospectively evaluated.

Examination of beam profile measurement using an imaging plate by the light exposure fading method for quality assurance of external radiation therapy.

High-resolution film dosimetry has been used for several decades to check and to measure two-dimensional dose distributions. However, in recent years, the automatic processor has been replaced by the spread of computed radiography, or has been little used hospitals. In this study, we measured the off-center ratio (OCR) of the open field, after an irradiating radiation beam was delivered to the imaging plate (IP) under conditions in which the IP was exposed to a fixed amount of light with fading, and compared these data with the OCR measured by an ionization-chamber dosimeter, which is the standard method used for measuring radiation dose.

[Characteristic evaluation of a real-time silicon dosimeter and measurement of entrance surface dose at radiography].

It is important to grasp how much radiation exposure has occurred through radiation diagnosis, in respect to patient explanations and radiation protection. In this examination, we used a patient skin dosimeter (PSD) that measures entrance surface dose (ESD) in real time using a fluoroscopy procedure. The PSD has the ability to display results beginning at 1 microGy.