The purpose of this study was to implement the Monte Carlo method for clinical radiotherapy dose calculations. We used EGS4/BEAM code obtain phase-space data 6-20 MeV electron beams and 4, 6, 15 MV photon Varian Clinac 1800, 2100C, 2300CD accelerators. A multiple-source model reconstruct both beams, which retained accuracy beam data. reduced storage requirement by a factor 1000 accelerator simulation time 10 or more. Agreement within 2% achieved between calculations measurements...

In summary, SRS and SBRT require a team-based approach, staffed by appropriately trained credentialed specialists. training should become required part of radiation oncology residency Accreditation Medical Physics Educational Programs accredited clinical medical physics training. significant resources in personnel, specialized technology, implementation time. A thorough feasibility analysis to achieve the technical goals must be performed discussed with all including center administration....

A Monte Carlo user code, MCDOSE, has been developed for radiotherapy treatment planning (RTP) dose calculations. MCDOSE is designed as a calculation module suitable adaptation to host RTP systems. can be used both conventional photon/electron beam and intensity modulated (IMRT) planning. uses multiple-source model reconstruct the phase space. Based on simulated or measured data acquired during commissioning, source-model parameters are adjusted through an automated procedure. Beam modifiers...

This report is part of a series white papers commissioned for the American Society Radiation Oncology (ASTRO) Board Directors as ASTRO's Target Safely Campaign, focusing on role peer review an important component broad safety/quality assurance (QA) program. Peer one most effective means assuring quality qualitative, and potentially controversial, patient-specific decisions in radiation oncology. summarizes many areas throughout therapy that may benefit from application review. Each oncology...

Purpose: Incident learning plays a key role in improving quality and safety wide range of industries medical disciplines. However, implementing an effective incident system is complex, especially radiation oncology. One current barrier the lack technical standards to guide users or developers. This report, product initiative by Work Group on Prevention Errors Radiation Oncology American Association Physicists Medicine, provides recommendations for content structure databases Methods: A panel...

To develop a quality assurance (QA) program for the On‐Board Imager (OBI) system and to summarize results of these QA tests over extended periods from multiple institutions. Both radiographic cone‐beam computed tomography (CBCT) mode operation have been evaluated. The programs four institutions combined generate series evaluating performance Imager. consists three parts: (1) safety functionality, (2) geometry, (3) image quality. Safety functionality evaluate features clinical entire during...

The purpose of this work was to use Monte Carlo simulations verify the accuracy dose distributions from a commercial treatment planning optimization system (Corvus, Nomos Corp., Sewickley, PA) for intensity-modulated radiotherapy (IMRT). A has been implemented clinically improve and calculations. Further modifications were made compute in patient multiple fixed-gantry IMRT fields. experimental phantoms patients calculated used optimized plans generated by Corvus system. agreed with...

Photon beams of 4, 6 and 15 MV from Varian Clinac 2100C 2300C/D accelerators were simulated using the EGS4/BEAM code system. The modelled as a combination component modules (CMs) consisting target, primary collimator, exit window, flattening filter, monitor chamber, secondary ring photon jaws protection window. A full phase space file was scored directly above upper analysed beam data processing software, BEAMDP, to derive characteristics, such planar fluence, angular distribution, energy...

Every quality assurance process uncovers random and systematic errors. These errors typically consist of many small a very few number large that dominate the result. Quality practices in radiotherapy do not adequately differentiate between these two sources error. The ability to separate types would allow dominant source(s) error be efficiently detected addressed. In this work, statistical control is applied for purpose setting action thresholds theoretical development implementation...

Surface image guided, Linac-based radiosurgery (SIG-RS) is a modern approach for delivering that utilizes optical stereoscopic imaging to monitor the surface of patient during treatment in lieu using head frame immobilization. Considering novelty SIG-RS and severity errors associated with delivery large doses per fraction, risk assessment should be conducted identify potential hazards, determine their causes, formulate mitigation strategies. The purpose this work investigate combined...

We have investigated the tongue-and-groove effect on IMRT dose distributions for a Varian MLC. compared calculated using intensity maps with and without effect. Our results showed that, one intensity-modulated treatment field, maximum could be up to 10% of in distributions. For an multiple gantry angles (⩾5), difference between was hardly visible, less than 1.6% two typical clinical cases studied. After considering patient setup errors, were smoothed reduced insignificant differences plans...

This work investigates the feasibility of optimizing energy- and intensity-modulated electron beams for radiation therapy. A multileaf collimator (MLC) specially designed modulated radiotherapy (MERT) was investigated both experimentally by Monte Carlo simulations. An inverse-planning system based on dose calculations developed to optimize beam energy intensity achieve conformity target volumes near surface. The results showed that an MLC with 5 mm leaf widths could produce complex field...

Recently, energy- and intensity-modulated electron radiotherapy (MERT) has garnered a growing interest for the treatment of superficial targets. In this work, we carried out comparative dosimetry study to evaluate MERT, photon beam radiation therapy (IMRT) conventional tangential beams breast cancer. A Monte Carlo based planning system been investigated, which consists set software tools perform accurate dose calculation, optimization, leaf sequencing plan analysis. We have compared plans...

A new EGS4/PRESTA Monte Carlo user code, MCDOSE, has been developed as a routine dose calculation tool for radiotherapy treatment planning. It is suitable both conventional and intensity modulated radiation therapy. Two important features of MCDOSE are the inclusion beam modifiers in patient simulation implementation several variance reduction techniques. Before this can be used reliably clinical calculation, it must properly validated. The validation performed by comparing distributions...

Our aim was to correlate patterns of failure with target volume delineations in patients head and neck squamous cell carcinoma (HNSCC) treated intensity-modulated radiation therapy (IMRT) report subjective xerostomia outcomes after IMRT as compared conventional (CRT).Between January 2000 April 2005, 69 newly diagnosed nonmetastatic HNSCC underwent curative parotid-sparing at Stanford University. Sites included were oropharynx (n = 39), oral cavity 8), larynx hypopharynx unknown primary 6)....

Currently, high-precision delivery in stereotactic radiosurgery (SRS) is achieved via target localization and rigid patient immobilization. Rigid immobilization can result in, however, discomfort, which exacerbated by the long duration of SRS treatments may induce movement. To address this issue, we developed a new technique that aimed to minimize discomfort while maintaining treatment, based on less-rigid combined with continuous motion monitoring. In paper, examine feasibility technique....