Production of neutrons in laminated barriers of radiotherapy rooms: comparison between the analytical methodology and Monte Carlo simulations.

abstract：PURPOSE:To provide insight into the types of questions asked to medical physicists by patients during one-on-one physicist-patient consults at one institution. MATERIALS AND METHODS:Medical physicists trained in patient communication techniques met with patients to provide an overview of the treatment planning and del...

journal_title：Journal of applied clinical medical physics

authors： Atwood TF,Brown DW,Juang T,Moore KL,McConnell KA,Steers JM,Murphy JD,Mundt AJ,Pawlicki T

更新日期：2020-08-01 00:00:00

abstract：:We report our technique for hemibody skin electron irradiation with a custom-made plywood shield. The technique is similar to our clinical total skin electron irradiation (TSEI), performed with a six-pair dual field (Stanford technique) at an extended source-to-skin distance (SSD) of 377 cm, with the addition of a ply...

journal_title：Journal of applied clinical medical physics

authors： Rivers CI,AlDahlawi I,Wang IZ,Singh AK,Podgorsak MB

更新日期：2016-11-08 00:00:00

abstract：:The aim of this study was to report a single-institution experience and commissioning data for Elekta VersaHD linear accelerators (LINACs) for photon beams in the Eclipse treatment planning system (TPS). Two VersaHD LINACs equipped with 160-leaf collimators were commissioned. For each energy, the percent-depth-dose (P...

journal_title：Journal of applied clinical medical physics

authors： Zhang Y,Le AH,Tian Z,Iqbal Z,Chiu T,Gu X,Pugachev A,Reynolds R,Park YK,Lin MH,Stojadinovic S

更新日期：2019-10-01 00:00:00

abstract：:Monte Carlo simulations are widely used for calculation of the dosimetric parameters of brachytherapy sources. MCNP4C2, MCNP5, MCNPX, EGS4, EGSnrc, PTRAN, and GEANT4 are among the most commonly used codes in this field. Each of these codes utilizes a cross-sectional library for the purpose of simulating different elem...

journal_title：Journal of applied clinical medical physics

authors： Zaker N,Zehtabian M,Sina S,Koontz C,Meigooni AS

更新日期：2016-03-08 00:00:00

abstract：:The purpose of this study was to evaluate the dose differences introduced by the TMR 10 and the convolution dose calculation algorithms in GammaPlan version 10, as compared to the TMR classic algorithm in the previous versions of GammaPlan. Computed axial tomographic images of a polystyrene phantom and a human head we...

journal_title：Journal of applied clinical medical physics

authors： Xu AY,Bhatnagar J,Bednarz G,Niranjan A,Flickinger J,Lunsford LD,Huq MS

更新日期：2014-09-08 00:00:00

abstract：PURPOSE:To investigate the effect of the marker placement on the correlation relationship between the motions of external markers and the internal target under different breathing patterns for several lung cancer patients. METHOD AND MATERIAL:To monitor and record simultaneous motions of internal target and associated...

journal_title：Journal of applied clinical medical physics

authors： Yan H,Zhu G,Yang J,Lu M,Ajlouni M,Kim JH,Yin FF

更新日期：2008-04-16 00:00:00

abstract：:We have developed a treatment planning protocol for intensity-modulated radiation therapy of the prostate using commercially available inverse planning software. Treatment plans were developed for ten patients using the Corvus version 3.8 planning system, testing various prescription options, including tissue types, d...

journal_title：Journal of applied clinical medical physics

authors： Ezzell GA,Schild SE,Wong WW

更新日期：2001-04-01 00:00:00

abstract：:Chest wall radiation therapy treatment delivery was monitored using a 5 mm thick radiochromic poly(vinyl alcohol) cryogel that also provided buildup material. The cryogels were used to detect positioning errors and measure the impact of shifts for a chest wall treatment that was delivered to a RANDO phantom. The phant...

journal_title：Journal of applied clinical medical physics

authors： Eyadeh MM,Weston MA,Juhasz J,Diamond KR

更新日期：2016-09-08 00:00:00

abstract：:The American Association of Physicists in Medicine Task Group 36 (AAPM TG-36) data can be used to estimate peripheral dose (PD) distributions outside the primary radiation field. However, the report data does not apply to linear accelerators equipped with a multileaf collimator (MLC) and universal wedge (UW). Tertiary...

journal_title：Journal of applied clinical medical physics

authors： Mutic S,Esthappan J,Klein EE

更新日期：2002-10-01 00:00:00

abstract：:This study extends the 'zero scan' method for CT imaging of polymer gel dosimeters to include multislice acquisitions. Multislice CT images consisting of 24 slices of 1.2 mm thickness were acquired of an irradiated polymer gel dosimeter and processed with the zero scan technique. The results demonstrate that zero scan...

journal_title：Journal of applied clinical medical physics

authors： Kakakhel MB,Kairn T,Charles P,Trapp JV

更新日期：2014-07-08 00:00:00

abstract：OBJECTIVE:To evaluate the accuracy of a deep learning-based auto-segmentation mode to that of manual contouring by one medical resident, where both entities tried to mimic the delineation "habits" of the same clinical senior physician. METHODS:This study included 125 cervical cancer patients whose clinical target volu...

journal_title：Journal of applied clinical medical physics

authors： Wang Z,Chang Y,Peng Z,Lv Y,Shi W,Wang F,Pei X,Xu XG

更新日期：2020-12-01 00:00:00

abstract：:The American Association of Physicists in Medicine (AAPM) is a nonprofit professional society whose primary purposes are to advance the science, education and professional practice of medical physics. The AAPM has more than 8,000 members and is the principal organization of medical physicists in the United States. The...

journal_title：Journal of applied clinical medical physics

authors： Smilowitz JB,Das IJ,Feygelman V,Fraass BA,Kry SF,Marshall IR,Mihailidis DN,Ouhib Z,Ritter T,Snyder MG,Fairobent L,AAPM Medical Physics Practice Guideline Task Group.

更新日期：2015-09-08 00:00:00

abstract：:For most computed tomography (CT) simulators, radiation therapists must remove the flat couch top to perform daily CT quality assurance (QA), and then use separate tools to perform localization-laser QA. This process wastes time and effort and creates the opportunity for accidents to occur. In this study, we tested a ...

journal_title：Journal of applied clinical medical physics

authors： Liu RR,Prado K,Gillin M

更新日期：2009-06-17 00:00:00

abstract：:As proton therapy becomes increasingly popular, so does the need for Monte Carlo simulation studies involving accurate beam line modeling of proton treatment units. In this study, the 24 beam configurations of the Mevion S250 proton therapy system installed recently at our institution were modeled using the TOolkit fo...

journal_title：Journal of applied clinical medical physics

authors： Prusator M,Ahmad S,Chen Y

更新日期：2017-05-01 00:00:00

abstract：:We have investigated the combined effect of tissue heterogeneity and its variation associated with geometric error in stereotactic body radiotherapy (SBRT) for lung cancer. The treatment plans for eight lung cancer patients were calculated using effective path length (EPL) correction and Monte Carlo (MC) algorithms, w...

journal_title：Journal of applied clinical medical physics

authors： Kang KM,Jeong BK,Choi HS,Yoo SH,Hwang UJ,Lim YK,Jeong H

更新日期：2015-09-08 00:00:00

abstract：:In this study, we compared the amount of lung tissue irradiated when respiratory gating was imposed during expiration with the amount of lung tissue irradiated when gating was imposed during inspiration. Our hypothesis was that the amount of lung tissue spared increased as inspiration increased. Computed tomography (C...

journal_title：Journal of applied clinical medical physics

authors： Butler LE,Forster KM,Stevens CW,Bloch C,Liu HH,Tucker SL,Komaki R,Liao Z,Starkschall G

更新日期：2004-01-01 00:00:00

abstract：:Flattening filter-free (FFF) beams are becoming the preferred beam type for stereotactic radiosurgery (SRS) and stereotactic ablative radiation therapy (SABR), as they enable an increase in dose rate and a decrease in treatment time. This work assesses the effects of the flattening filter on small field output factors...

journal_title：Journal of applied clinical medical physics

authors： Tyler MK,Liu PZ,Lee C,McKenzie DR,Suchowerska N

更新日期：2016-05-08 00:00:00

abstract：:Relative dose measurements with small ionization chambers in combination with an electrometer placed in the treatment room ("internal electrometer") show a large dependence on the polarity used. While this was observed previously for percent depth dose curves (PDDs), the effect has not been understood or preventable. ...

journal_title：Journal of applied clinical medical physics

authors： Wegener S,Sauer OA

更新日期：2018-11-01 00:00:00

abstract：:The nonphysical wedge is a modality that uses computer-controlled jaw motion to generate wedge-shaped dose distributions. There are Varian enhanced dynamic wedges (EDWs) and Siemens virtual wedges (VWs). We recently commissioned dynamic wedges on both Varian and Siemens LINACs. The beam data, acquired with a Wellhofer...

journal_title：Journal of applied clinical medical physics

authors： Shao H,Wu X,Luo C,Crooks A,Bernstein A,Markoe A

更新日期：2004-10-01 00:00:00

abstract：:Increasingly, the advent of multislice CT scanners, volume CT scanners, and total body spiral acquisition modes has led to the use of Multi Planar Reconstruction and 3D datasets. In considering 3D resolution properties of a CT system it is important to note that both the in-plane (x,y) and z-axis (slice thickness) inf...

journal_title：Journal of applied clinical medical physics

authors： Goodenough D,Levy J,Kristinsson S,Fredriksson J,Olafsdottir H,Healy A

更新日期：2016-09-08 00:00:00

abstract：:Highly attenuating radiation treatment couches are no longer useful in the present era of radiotherapy utilizing IMRT and IGRT. Carbon fibers couch tops with its high tensile strength and low density present a useful alternative. The objective of the current study was to quantify the attenuation of megavoltage photons...

journal_title：Journal of applied clinical medical physics

authors： Njeh CF,Raines TW,Saunders MW

更新日期：2009-06-02 00:00:00

abstract：PURPOSE:To determine the optimal dose-volume constraint for laryngeal sparing using three commonly employed intensity modulated radiation therapy (IMRT) approaches in patients with oropharyngeal cancer treated to the bilateral neck. MATERIALS AND METHODS:Thirty patients with stage II-IVA oropharynx cancers received de...

journal_title：Journal of applied clinical medical physics

authors： Wilke C,Takiar V,Wang H,Moreno AC,Tung SS,Quinlan-Davidson SR,Garden AS,Rosenthal DI,Fuller CD,Gunn GB,Reddy JP,Morrison WH,Wang C,Zhao G,Hutcheson KA,Phan J

更新日期：2020-12-05 00:00:00

abstract：:TomoEDGE is an advanced delivery form of tomotherapy which uses a dynamic secondary collimator. This plan comparison study describes the new features, their clinical applicability, and their effect on plan quality and treatment speed. For the first 45 patients worldwide that were scheduled for a treatment with TomoEdg...

journal_title：Journal of applied clinical medical physics

authors： Katayama S,Haefner MF,Mohr A,Schubert K,Oetzel D,Debus J,Sterzing F

更新日期：2015-03-08 00:00:00

abstract：:We assessed interfraction positional variation in pancreatic tumors using daily breath-hold cone-beam computed tomography at end-exhalation (EE) with visual feedback (BH-CBCT). Eleven consecutive patients with pancreatic cancer who underwent BH intensity-modulated radiation therapy with visual feedback were enrolled. ...

journal_title：Journal of applied clinical medical physics

authors： Nakamura M,Akimoto M,Ono T,Nakamura A,Yano S,Nakata M,Itasaka S,Mizowaki T,Shibuya K,Hiraoka M

更新日期：2015-03-08 00:00:00

abstract：PURPOSE:To report our early experiences with failure mode and effects analysis (FMEA) in a community practice setting. METHODS:The FMEA facilitator received extensive training at the AAPM Summer School. Early efforts focused on department education and emphasized the need for process evaluation in the context of high ...

journal_title：Journal of applied clinical medical physics

authors： Schuller BW,Burns A,Ceilley EA,King A,LeTourneau J,Markovic A,Sterkel L,Taplin B,Wanner J,Albert JM

更新日期：2017-11-01 00:00:00

abstract：:We have developed a method to improve the setup accuracy of a Varian Clinac 6/100 couch for delivering conformal arc therapy using a tertiary micro multileaf collimator (MLC) system. Several immobilization devices have been developed to improve the mechanical stability and isocenter alignment of the couch: turn-knob h...

journal_title：Journal of applied clinical medical physics

authors： Li K,Yu CX,Ma L

更新日期：2004-07-01 00:00:00

abstract：:The purpose of this work is to prospectively assess the setup accuracy that can be achieved with a stereotactic body localizer (SBL) in immobilizing patients for stereotactic intensity-modulated radiotherapy (IMRT) for prostate cancer. By quantifying this important factor and target mobility in the SBL, we expect to p...

journal_title：Journal of applied clinical medical physics

authors： Wang L,Jacob R,Chen L,Ma C,Movsas B,Feigenberg S,Konski A

更新日期：2004-04-01 00:00:00

abstract：:Longitudinal partial volume effects (z-axial PVE), which occur when an object partly occupies a slice, degrade image resolution and contrast in computed tomography (CT). Z-axial PVE is unavoidable for subslice objects and reduces their contrast according to their fraction contained within the slice. This effect can be...

journal_title：Journal of applied clinical medical physics

authors： Monnin P,Sfameni N,Gianoli A,Ding S

更新日期：2017-01-01 00:00:00

abstract：:This study evaluated unexpected dosimetric errors caused by machine control accuracy, patient setup errors, and patient weight changes/internal organ deformations. Trajectory log files for 13 gynecologic plans with seven- or nine-beam dynamic multileaf collimator (MLC) intensity-modulated radiation therapy (IMRT), and...

journal_title：Journal of applied clinical medical physics

authors： Utena Y,Takatsu J,Sugimoto S,Sasai K

更新日期：2021-01-10 00:00:00

abstract：PURPOSE:To assess the impact of isocenter shifts due to linac gantry and table rotation during cranial stereotactic radiosurgery on D98 , target volume coverage (TVC), conformity (CI), and gradient index (GI). METHODS:Winston-Lutz (WL) checks were performed on two Elekta Synergy linacs. A stereotactic quality assuranc...

journal_title：Journal of applied clinical medical physics

authors： Wack LJ,Exner F,Wegener S,Sauer OA

更新日期：2020-05-01 00:00:00