Current state-of-the art digital C-arm medical linear accelerators are capable of delivering radiation treatments with high level of automation, which affords coordinated motions of gantry, couch, and multileaf collimator (MLC) with dose rate modulations. The new machine capacity has shown the potential to bring substantially improved radiation dosimetry and/or delivery efficiency to many chall...

Quantification of the setup errors is vital to define appropriate setup margins preventing geographical misses. The no-action-level (NAL) correction protocol reduces the systematic setup errors and, hence, the setup margins. The manual entry of the setup corrections in the record-and-verify software, however, increases the susceptibility of the NAL protocol to human errors. Moreover, the impact...

With the purpose of reducing stray radiation dose (SRD) in out-of-field region (OFR) during radiotherapy with 6 MV intensity-modulated radiation therapy (IMRT), a body-shielding device (BSD) was prepared according to the measurements obtained in experimental testing. In experimental testing, optimal shielding conditions, such as 1 mm lead, 2 mm lead, and 1 mm lead plus 10 mm bolus, were investi...

background: the presence of small intestine in the radiation field during pelvic cancers treatment causes an interruption in radiotherapy. a non-invasive method was developed to exclude small intestine during conventional radiotherapy. materials and methods: the incidence of the radiation therapy interruption is highly dependent upon the area of the small intestine included in the portals and i...

A positioning QA procedure for Varian's 2D/2D (kV/MV) and 3D/3D (planCT/CBCT) matching was developed. The procedure was to check: (1) the coincidence of on-board imager (OBI), portal imager (PI), and cone beam CT (CBCT)'s isocenters (digital graticules) to a linac's isocenter (to a pre-specified accuracy); (2) that the positioning difference detected by 2D/2D (kV/MV) and 3D/3D(planCT/CBCT) matc...

Leterrier’s recent blockbuster, Clash of the Titans (2010), tells the story of the most famous adventures of Perseus, son of Zeus and the mortal Danaë, as he defeats the Gorgon Medusa before rescuing Andromeda, daughter of king Cepheus, from the gigantic sea monster. The basic details of these mythical adventures can be found in ancient sources. Furthermore, the film pays an immediate tribute t...

Purpose: To study the effect of Qfix kVue Calypso-compatible couch top on dosimetry Spine Stereotactic Body Radiation Therapy (SBRT). Methods and Materials: The computed tomography (CT) data set for with rails were imported into treatment planning system (TPS). Nine patients who underwent spine SBRT selected this study. inclusion criteria included treated a stereotactic linear accelerator 5 fra...

With conventional diagnostic X-ray machines with over couch X-ray tubes, it is not possible to obtain anteroposterior (AP) and lateral (Lat) radiographs without changing the posture of the patients. In an old 300 mA X-ray machine with a fluoroscopy screen (12.4 kg) (1995 model), by substituting the screen with suitable counterweight and making provision to take the hoist pillar up to the edge o...

Carboxylation Reactions and Photosynthesis: 5 _ _ Sevtero Ochoa and Wolf Vishniac .... ................ . . 997 James Fitton Couch: 1888-1951: B. A. Brice ....301 News and Notes International Statistical Conference: N. R. Sriuirasan ... 302 Technical Papers Relation of Prothrombin to the Prolongation of Clotting Timiie in Aestivating Ground Squirrels: Arthur Svihla, Howard Bowman, and Ruth Rite...

abstract background: adjacent treatment fields are commonly used in external beam radiation therapy, such as mantle and inverted-y fields for the treatment of hodgkin’s disease and craniospinal fields used in the treatment of medulloblastoma and head and neck tumors when the lateral neck fields are placed adjacent to the anterior supraclavicular field. in each of these situations, there is a po...