Use of a radioactive check device for redundancy check of ionization chambers.

abstract：:Measurement of cumulative dose ƒ(0,150) with a small ionization chamber within standard polymethyl methacrylate (PMMA) CT head and body phantoms, 150 mm in length, is a possible practical method for cone-beam computed tomography (CBCT) dosimetry. This differs from evaluating cumulative dose under scatter equilibrium c...

journal_title：Journal of applied clinical medical physics

authors： Abuhaimed A,Martin CJ,Sankaralingam M,Oomen K,Gentle DJ

更新日期：2015-11-08 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：:During volume-modulated arc therapies (VMAT), dosimetric errors are introduced by multiple open dynamic leaf gaps that are present in fixed diaphragm linear accelerators. The purpose of this work was to develop a methodology for adjusting the rounded leaf end modeling parameters to improve out-of-field dose agreement ...

journal_title：Journal of applied clinical medical physics

authors： Young LA,Yang F,Cao N,Meyer J

更新日期：2016-11-08 00:00:00

abstract：:This is a proof-of-concept study demonstrating the capacity for modulated electron radiation therapy (MERT) dose distributions using 3D printed bolus. Previous reports have involved bolus design using an electron pencil beam model and fabrication using a milling machine. In this study, an in-house algorithm is present...

journal_title：Journal of applied clinical medical physics

authors： Su S,Moran K,Robar JL

更新日期：2014-07-08 00:00:00

abstract：:Dental amalgams are a common source of artifacts in head and neck (HN) images. Commercial artifact reduction techniques have been offered, but are substantially ineffectual at reducing artifacts from dental amalgams, can produce additional artifacts, provide inaccurate HU information, or require extensive computation ...

journal_title：Journal of applied clinical medical physics

authors： Branco D,Kry S,Taylor P,Rong J,Zhang X,Peterson C,Frank S,Followill D

更新日期：2020-08-01 00:00:00

abstract：:Atlas-based autosegmentation is an established tool for segmenting structures for CT-planned head and neck radiotherapy. MRI is being increasingly integrated into the planning process. The aim of this study is to assess the feasibility of MRI-based, atlas-based autosegmentation for organs at risk (OAR) and lymph node ...

journal_title：Journal of applied clinical medical physics

authors： Wardman K,Prestwich RJ,Gooding MJ,Speight RJ

更新日期：2016-07-08 00:00:00

abstract：:Optimal choice of beam energy in radiation therapy is easy in many well-documented cases, but less obvious in some others. Low-energy beams may provide better conformity around the target than their high-energy counterparts due to reduced lateral scatter, but they also contribute to overdosage of peripheral normal tis...

journal_title：Journal of applied clinical medical physics

authors： St-Hilaire J,Sévigny C,Beaulieu F,Gingras L,Tremblay D,Beaulieu L

更新日期：2009-09-03 00:00:00

abstract：:Significant controversy surrounds the 2012 / 2014 decision announced by the Trustees of the American Board of Radiology (ABR) in October of 2007. According to the ABR, only medical physicists who are graduates of a Commission on Accreditation of Medical Physics Education Programs, Inc. (CAMPEP) accredited academic or ...

journal_title：Journal of applied clinical medical physics

authors： Mills MD,Thornewill J,Esterhay RJ

更新日期：2010-04-12 00:00:00

abstract：:Radiographic film dosimetry provides fast, convenient 2-D dose distributions, but is challenged by the dependence of film response on scatter conditions (i.e., energy dependence). Verification of delivered dose in the surface buildup region is important for intensity modulated radiation therapy (IMRT) when volumes of ...

journal_title：Journal of applied clinical medical physics

authors： Roberson PL,Moran JM,Kulasekere R

更新日期：2008-10-24 00:00:00

abstract：:A patient with a cardiac ventricular assist device (VAD) with computer-controlled driver presented to our department for radiation therapy. The treatment plan was 4500 cGy to the rectum over 25 fractions with 15MV photon beams. All beams avoided the pump and leads. The response to electromagnetic interference (EMI) wa...

journal_title：Journal of applied clinical medical physics

authors： Lasher DE,Wojcicka JB,Malcom R,Shears LL

更新日期：2008-10-29 00:00:00

abstract：INTRODUCTION:Aim of this study is to dosimetrically characterize a new inorganic scintillator designed for magnetic resonance-guided radiotherapy (MRgRT) in the presence of 0.35 tesla magnetic field (B). METHODS:The detector was characterized in terms of signal to noise ratio (SNR), reproducibility, dose linearity, an...

journal_title：Journal of applied clinical medical physics

authors： Cusumano D,Placidi L,D'Agostino E,Boldrini L,Menna S,Valentini V,De Spirito M,Azario L

更新日期：2020-09-01 00:00:00

abstract：:Many head-and-neck cancer (HNC) patients treated with radiotherapy suffer significant anatomical changes due to tumor shrinkage or weight loss. The purpose of this study was to assess dose changes over target volumes and organs at risk during intensity-modulated radiotherapy for HNC patients. Sixteen HNC IMRT patients...

journal_title：Journal of applied clinical medical physics

authors： Beltran M,Ramos M,Rovira JJ,Perez-Hoyos S,Sancho M,Puertas E,Benavente S,Ginjaume M,Giralt J

更新日期：2012-11-08 00:00:00

abstract：:The purpose of this study was to develop and evaluate filmless quality assurance (QA) tools for helical tomotherapy by using the signals from the on-board megavoltage computed tomography (MVCT) detector and applying a dedicated step-wedge phantom. The step-wedge phantom is a 15 cm long step-like aluminum block positio...

journal_title：Journal of applied clinical medical physics

authors： Althof V,van Haaren P,Westendorp R,Nuver T,Kramer D,Ikink M,Bel A,Minken A

更新日期：2012-01-05 00:00:00

abstract：:A wide variety of existing combinations of target and filter materials (target/filter combinations) are used in mammography equipment. The patient dose depends on the X-ray quality that is derived from the target/filter combination, and a calibration of the dosimeter that is used in the measurement that corresponds to...

journal_title：Journal of applied clinical medical physics

authors： Sekimoto M,Katoh Y,Katoh T

更新日期：2015-11-08 00:00:00

abstract：:It is important to improve the magnitude of dose variation that is caused by the interplay effect. The aim of this study was to investigate the impact of the number of breaths (NBs) to the dose variation for VMAT-SBRT to lung cancer. Data on respiratory motion and multileaf collimator (MLC) sequence were collected fro...

journal_title：Journal of applied clinical medical physics

authors： Kubo K,Monzen H,Tamura M,Hirata M,Ishii K,Okada W,Nakahara R,Kishimoto S,Kawamorita R,Nishimura Y

更新日期：2018-03-01 00:00:00

abstract：:Precise radiation therapy (RT) for abdominal lesions is complicated by respiratory motion and suboptimal soft tissue contrast in 4D CT. 4D MRI offers improved con-trast although long scan times and irregular breathing patterns can be limiting. To address this, visual biofeedback (VBF) was introduced into 4D MRI. Ten v...

journal_title：Journal of applied clinical medical physics

authors： To DT,Kim JP,Price RG,Chetty IJ,Glide-Hurst CK

更新日期：2016-05-08 00:00:00

abstract：:The purpose of this study is to find the uncertainties in the reconstruction of MR compatible ring-tandem intracavitary applicators of high-dose rate image-based brachytherapy treatment planning using rigid registration of 3D MR and CT image fusion. Tandem and ring reconstruction in MR image based brachytherapy planni...

journal_title：Journal of applied clinical medical physics

authors： Oinam AS,Tomar P,Patel FD,Singh L,Rai B,Bahl A

更新日期：2014-03-06 00:00:00

abstract：:Treatment planning for breast cancer has been traditionally based on clinical landmarks. The Radiation Therapy Oncology Group (RTOG) published consensus guidelines on contouring target volumes (TV) for the breast/chest wall and draining lymphatics. The effect of these guidelines on dosimetric parameters in surrounding...

journal_title：Journal of applied clinical medical physics

authors： Rudra S,Al-Hallaq HA,Feng C,Chmura SJ,Hasan Y

更新日期：2014-03-06 00:00:00

abstract：:We describe a method for independently verifying the dose distributions from pre- and post-implant brachytherapy source distributions. Monte Carlo calculations have been performed to characterize the three-dimensional dose distribution in water phantom from a low-energy brachytherapy source. The calculations are perfo...

journal_title：Journal of applied clinical medical physics

authors： DeMarco JJ,Solberg TD,Agazaryan N

更新日期：2003-01-01 00:00:00

abstract：:We examined the dose distributions generated by Pinnacle3 (Philips Radiation Oncology Systems, Milpitas, CA) for intensity-modulated radiotherapy (IMRT) plans using a cubic-block-piled compensator as the intensity modulator for 4-MV and 10-MV photon beams. The Pinnacle treatment planning system (TPS) uses an algorithm...

journal_title：Journal of applied clinical medical physics

authors： Sasaki K,Obata Y

更新日期：2006-06-16 00:00:00

abstract：:The impact of the treatment couch on a radiotherapy plan is rarely fully assessed during the treatment planning process. Incorporating a couch model into the treatment planning system (TPS) enables the planner to avoid or dosimetrically evaluate beam-couch intersections. In this work, we demonstrate how existing TPS t...

journal_title：Journal of applied clinical medical physics

authors： Van Prooijen M,Kanesalingam T,Islam MK,Heaton RK

更新日期：2010-04-19 00:00:00

abstract：:Recently, specific computed tomography (CT) scanners have been equipped with organ-based tube current modulation (TCM) technology. It is possible that organ-based TCM will replace the conventional dose-reduction technique of reducing the effective milliampere-second. The aim of this study was to determine if organ-bas...

journal_title：Journal of applied clinical medical physics

authors： Matsubara K,Sugai M,Toyoda A,Koshida H,Sakuta K,Takata T,Koshida K,Iida H,Matsui O

更新日期：2012-03-08 00:00:00

abstract：:A new version of progressive resolution optimizer (PRO) with an option of air cavity correction has been implemented for RapidArc volumetric-modulated arc therapy (RA). The purpose of this study was to compare the performance of this new PRO with the use of air cavity correction option (PRO10_air) against the one with...

journal_title：Journal of applied clinical medical physics

authors： Kan MW,Leung LH,Yu PK

更新日期：2013-11-04 00:00:00

abstract：:The purpose of this study was to investigate amplitude gating combined with a coached breathing strategy for 10 MV flattening filter-free (FFF) volumetric-modulated arc therapy (VMAT) on the Varian TrueBeam linac. Ten patient plans for VMAT SABR liver were created using the Eclipse treatment planning system (TPS). The...

journal_title：Journal of applied clinical medical physics

authors： Viel F,Lee R,Gete E,Duzenli C

更新日期：2015-07-08 00:00:00

abstract：:Physical and dosimetric characteristics of HDMLC were studied for SRS6, 6, and 10 MV X-rays from Novalis Tx. This in-built tertiary collimator consists of 60 pairs (32 × 0.25 cm; 26 × 0.5 cm and 2 × 0.7 cm) of leaves. Properties of HDMLC studied included alignment, readout and radiation field congruence, radiation pen...

journal_title：Journal of applied clinical medical physics

authors： Sharma DS,Dongre PM,Mhatre V,Heigrujam M

更新日期：2011-04-14 00:00:00

abstract：:Substantial disagreement exists over appropriate PET segmentation techniques for non-small cell lung cancer. Currently, no segmentation algorithm explicitly considers tumor motion in determining tumor borders. We developed an automatic PET segmentation model as a function of target volume, motion extent, and source-to...

journal_title：Journal of applied clinical medical physics

authors： Riegel AC,Bucci MK,Mawlawi OR,Ahmad M,Luo D,Chandler A,Pan T

更新日期：2014-01-06 00:00:00

abstract：:A new calculation algorithm has been developed for independently verifying doses calculated by the TomoTherapy Hi.Art treatment planning system (TPS). The algorithm is designed to confirm the dose to a point in a high dose, low dose-gradient region. Patient data used by the algorithm include the radiological depth to ...

journal_title：Journal of applied clinical medical physics

authors： Gibbons JP,Smith K,Cheek D,Rosen I

更新日期：2009-02-05 00:00:00

abstract：:In this work, the feasibility of using flattening filter free (FFF) beams in volumetric modulated arc therapy (VMAT) total body irradiation (TBI) treatment planning to decrease protracted beam-on times for these treatments was investigated. In addition, a methodology was developed to generate standardized VMAT TBI tre...

journal_title：Journal of applied clinical medical physics

authors： Frederick R,Hudson A,Balogh A,Cao JQ,Pierce G

更新日期：2020-03-01 00:00:00

abstract：:A method to evaluate the electron beam energy constancy by employing the computed radiography (CR) system has been developed. In this method, a right triangular plastic wedge is used to produce a curve of the CR storage phosphor plate signal versus the wedge thickness. The curve, which resembles the percentage depth i...

journal_title：Journal of applied clinical medical physics

authors： Cai YC,Ge Y,Bernard D,Turian J,Chu JCH

更新日期：2009-10-15 00:00:00

abstract：:A patient specific quality assurance (QA) should detect errors that originate anywhere in the treatment planning process. However, the increasing complexity of treatment plans has increased the need for improvements in the accuracy of the patient specific pretreatment verification process. This has led to the utilizat...

journal_title：Journal of applied clinical medical physics

authors： Defoor DL,Stathakis S,Roring JE,Kirby NA,Mavroidis P,Obeidat M,Papanikolaou N

更新日期：2017-07-01 00:00:00