PURPOSE Linac parameters potentially influencing the delivery quality of IMRT and VMAT plans are investigated with respect to threshold ranges, consequently to be considered in a linac based quality assurance procedure. Three commercially available 2D arrays are used to further investigate the influence of the measurement device. METHODS Using three commercially available 2D arrays (Mx: Matri...

BACKGROUND The modalities for performing stereotactic radiotherapy (SRT) on the brain include the cone-based linear accelerator (linac), the flattening filter-free (FFF) volumetric modulated arc therapy (VMAT) linac, and tomotherapy. In this study, the cone-based linac, FFF-VMAT linac, and tomotherapy modalities were evaluated by measuring the differences in doses delivered during brain SRT and...

The authors report the first magnetic resonance (MR) images produced by their prototype MR system integrated with a radiation therapy source. The prototype consists of a 6 MV linac mounted onto the open end of a biplanar 0.2 T permanent MR system which has 27.9 cm pole-to-pole opening with flat gradients (40 mT/m) running under a TMX NRC console. The distance from the magnet isocenter to the li...

Two bunching schemes are considered in the frame of the CPS Linac, one with a single buncher, the other with a double-drift harmonic buncher. The matching of the beam to the Linac acceptance in six phase-space dimensions is achieved by computer programs in an iterative way: zero current solutions are found first, and then the intensity is progressively raised until 200 mA are trapped into the L...

background: the advancement of technology in recent decades has been lead to use the electrophysiology cardiac devices. although these devices are used increasingly, but the frequency of subclinical infection is unknown. we investigate bacterial infections due to implantable cardioverter defibrillator (icds) in patients with endocarditis. m aterials and methods: population of the study was cons...

Background: During intensity modulated radiation therapy (IMRT) technique, theoretically, presence of flattening filter (FF) across the beamline of clinical linear accelerator (linac) is not essential to obtain uniform lateral profiles due to intensity modulation of photon beams by multileaf collimators (MLCs). The aim of this study was to investigate the dosimetrical properties of 18 MV photon...

Introduction: In clinical electron beams, most of bremsstrahlung radiation is produced by various linac head structures. This bremsstrahlung radiation dose is influenced by the geometry and construction of every component of the linac treatment head structures. Thus, it can be expected that the amount of the contaminated photon dose due to bremsstrahlung radiation varies among different linacs,...