IMRT QA requires, among other tests, a time-consuming process of measuring the absorbed dose, at least to a point, in a high-dose, low-dose-gradient region. Some clinics use a technique of measuring this dose with all beams delivered at a single gantry angle (collapsed delivery), as opposed to the beams delivered at the planned gantry angle (rotated delivery). We examined, established, and opti...

BACKGROUND This study investigates the effect of gantry speed on 4DCBCT image quality and dose for the Varian On-Board Imager®. METHODS A thoracic 4DCBCT protocol was designed using a 125 kVp spectrum. Image quality parameters were evaluated for 4DCBCT acquisition using Catphan® phantom with real-time position management™ system for gantry speeds varying between 1.0 to 6.0°/s. Superior-inferi...

In proton therapy, high dose rates can reduce treatment delivery times, allowing for efficient mitigation of tumor motion, as well increased efficiency and patient throughput. cyclotron-based facilities, however, are difficult to achieve at low-energies. current the emittance after degrader is matched in both transversal planes using circular collimators; this does not provide an optimal matchi...

The dedicated new medical facility PROSCAN has restarted the treatment of deep seated tumours with proton beams at Gantry 1. The beam lines to the new gantry 2 for the further development of the spot-scanning technology, as well as to the replacement of the long established OPTIS facility for the treatment of eye melanoma, and to a material irradiation area, are in the commissioning phase. An o...

We developed a novel low-radiation-absorbent lok-bar (HM-bar) that is used to secure the immobilizers to the couch. The aim of this study was to investigate the X-ray scattering and absorption properties of the HM-bar in computed tomography (CT) simulation and radiotherapy dose delivery using the Varian Exact™ lok-bar (VL-bar) as a benchmark. CT images were obtained with or without lok-bar, and...

A software tool is developed, given a new treatment plan, to predict treatment delivery time for radiation therapy (RT) treatments of patients on ViewRay magnetic resonance image-guided radiation therapy (MR-IGRT) delivery system. This tool is necessary for managing patient treatment scheduling in our clinic. The predicted treatment delivery time and the assessment of plan complexities could al...

A novel three-dimensional unicursal irradiation technique "Dynamic WaveArc" (DWA), which employs simultaneous and continuous gantry and O-ring rotation during dose delivery, has been implemented in Vero4DRT. The purposes of this study were to develop a commissioning and quality assurance procedure for DWA irradiation, and to assess the accuracy of the mechanical motion and dosimetric control of...

A kind of parametric finite element analysis system for the L type gantry crane’s gate frame is developed by making use of the secondary development on the platform of ANSYS, MATLAB through VC++ programming. The interface technology of VC++, ANSYS, and MATLAB is employed as well as the encapsulation on APDL. To input parameter in the VC++ and to calculate the quality of the L type gantry crane ...

Robots are coming to conquer new domains of everyday life. They are used in fields such as education, entertainment and housekeeping more than ever. Roboshark, a gantry robot capable of playing pool games, can be used for both training amateur pool players and entertaining amateur or professional ones. Roboshark belongs to gantry robots family. It is located directly above the pool table – a cm...

Purpose: The aim of this study was to develop a method for the direct measurement of electron beam width and distribution at the scattering foil on the carrousel in a medical linear accelerator gantry head, which differs from an existing indirect method for measuring the focal spot size using a camera or metallic slit located outside the gantry head. Methods: The electron beam emitted by the li...