Effect of electron contamination on in vivo dosimetry for lung block shielding during TBI.

abstract：:The purpose of this study is to simulate random and systematic RapidArc delivery errors for external beam prostate radiotherapy plans in order to determine the dose sensitivity for each error type. Ten prostate plans were created with a single 360° arc. The DICOM files for these treatment plans were then imported into...

journal_title：Journal of applied clinical medical physics

authors： Oliver M,Bush K,Zavgorodni S,Ansbacher W,Beckham WA

更新日期：2011-05-20 00:00:00

abstract：:In radiation therapy, a secondary independent dose verification is an important component of a quality control system. Mobius3D calculates three-dimensional (3D) patient dose using reference beam data and a collapsed cone convolution algorithm and analyzes dose-volume histogram automatically. There are currently no pu...

journal_title：Journal of applied clinical medical physics

authors： Kodama T,Saito Y,Hatanaka S,Hariu M,Shimbo M,Takahashi T

更新日期：2019-05-01 00:00:00

abstract：:To estimate the lung tumor position from multiple anatomical features on four-dimensional computed tomography (4D-CT) data sets using single regression analysis (SRA) and multiple regression analysis (MRA) approach and evaluate an impact of the approach on internal target volume (ITV) for stereotactic body radiotherap...

journal_title：Journal of applied clinical medical physics

authors： Ono T,Nakamura M,Hirose Y,Kitsuda K,Ono Y,Ishigaki T,Hiraoka M

更新日期：2017-09-01 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：:The Vero4DRT (MHI-TM2000) is capable of performing X-ray image-based tracking (X-ray Tracking) that directly tracks the target or fiducial markers under continuous kV X-ray imaging. Previously, we have shown that irregular respiratory patterns increased X-ray Tracking errors. Thus, we assumed that audio instruction, w...

journal_title：Journal of applied clinical medical physics

authors： Nakamura M,Sawada A,Mukumoto N,Takahashi K,Mizowaki T,Kokubo M,Hiraoka M

更新日期：2013-09-06 00:00:00

abstract：:Two patients with multiple lung metastases (≥ 5) were treated using frameless stereotactic body radiation therapy (SBRT) on an Elekta Axesse linear accelerator equipped with an interdigitation-capable multileaf collimator and four-dimensional cone-beam CT (4D CBCT). The technique and the early clinical outcomes were e...

journal_title：Journal of applied clinical medical physics

authors： Li Q,Mu J,Gu W,Chen Y,Ning Z,Jin J,Pei H

更新日期：2014-07-08 00:00:00

abstract：:The objectives of this project are to quantify the dose reduction effect provided by a lead shield for patients with cardiac implantable electronic devices (CIED) during a clinically realistic radiation treatment on phantom and to provide a simple model of dose estimation to predict dose received by CIED in a wide ran...

journal_title：Journal of applied clinical medical physics

authors： Bourgouin A,Varfalvy N,Archambault L

更新日期：2015-11-08 00:00:00

abstract：:The management of a pregnant patient in radiation oncology is an infrequent event requiring careful consideration by both the physician and physicist. The aim of this manuscript was to highlight treatment planning techniques and detail measurements of fetal dose for a pregnant patient recently requiring treatment for ...

journal_title：Journal of applied clinical medical physics

authors： Labby ZE,Barraclough B,Bayliss RA,Besemer AE,Dunkerley DAP,Howard SP

更新日期：2018-09-01 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：BACKGROUND:We study the changes in organs-at-risk (OARs) morphology as contoured on serial MRIs during chemoradiation therapy (CRT) of glioblastoma (GBM). The dosimetric implication of assuming non-deformable OAR changes and the accuracy and feasibility of semi-automatic OAR contour propagation are investigated. METHO...

journal_title：Journal of applied clinical medical physics

authors： Lee S,Stewart J,Lee Y,Myrehaug S,Sahgal A,Ruschin M,Tseng CL

更新日期：2019-12-01 00:00:00

abstract：:Varian (Palo Alto, California, United States) recently released an online adaptation treatment platform, Ethos, which has introduced a new Dose Preview and Automated Plan Generation module despite sharing identical beam data with the existing Halcyon linac. The module incorporates a preconfigured beam model and the Ac...

journal_title：Journal of applied clinical medical physics

authors： Hu Y,Byrne M,Archibald-Heeren B,Collett N,Liu G,Aland T

更新日期：2020-12-01 00:00:00

abstract：:Stereotactic body radiation therapy (SBRT) has been increasingly used as an efficacious treatment modality for early-stage non-small cell lung cancer. The accuracy of dose calculations is compromised due to the presence of inhomogeneity. For the purpose of a consistent prescription, radiation doses were calculated wit...

journal_title：Journal of applied clinical medical physics

authors： Zhuang T,Djemil T,Qi P,Magnelli A,Stephans K,Videtic G,Xia P

更新日期：2013-03-04 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：: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：:Routine constancy checks of electron energy are often time consuming because of the necessity to measure a dose at two depths. A technique is described that uses a double-wedge shaped phantom positioned on a Profiler diode array for measuring an electron energy constancy metric similar to R(50). The double-wedge elect...

journal_title：Journal of applied clinical medical physics

authors： Wells DM,Picco PJ,Ansbacher W

更新日期：2003-07-01 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：PURPOSE:The weighted CT dose index (CTDIw ) has been extended for a nominal total collimation width (nT) greater than 40 mm and relies on measurements of CTDIfreeair. The purpose of this work was to compare three methods of measuring CTDIfreeair and subsequent calculations of CTDIw to investigate their clinical appropr...

journal_title：Journal of applied clinical medical physics

authors： Bujila R,Kull L,Danielsson M,Andersson J

更新日期：2018-07-01 00:00:00

abstract：:This paper aims to evaluate the impact of spectral filtration on image quality in a microcomputed tomography (micro-CT) system. A mouse phantom comprising 11rods for modeling lung, muscle, adipose, and bones was scanned with 17 s and 2min, respectively. The current (μA) for each scan was adjusted to achieve identical ...

journal_title：Journal of applied clinical medical physics

authors： Ren L,Ghani MU,Wu D,Zheng B,Chen Y,Yang K,Wu X,Liu H

更新日期：2016-01-08 00:00:00

abstract：:Using a plane-parallel advanced Markus ionization chamber and a stack of water-equivalent solid phantom blocks, percentage surface and build-up doses of Elekta 6 MV flattening filter (FF) and flattening-filter-free (FFF) beams were measured as a function of the phantom depth for field sizes ranging from 2 × 2 to 10 × ...

journal_title：Journal of applied clinical medical physics

authors： Imae T,Takenaka S,Watanabe Y,Aoki A,Matsuda K,Sasaki K,Saegusa S,Nawa K,Nakagawa K,Abe O

更新日期：2020-12-01 00:00:00

abstract：:A thorax phantom was used to assess radiotherapy dose deviations induced by respiratory motion of the target volume. Both intensity modulated and static, non-modulated treatment plans were planned on CT scans of the phantom. The plans were optimized using various CT reconstructions, to investigate whether they had an ...

journal_title：Journal of applied clinical medical physics

authors： Sande EPS,Acosta Roa AM,Hellebust TP

更新日期：2020-04-01 00:00:00

abstract：PURPOSE:To assess the noise characteristics of the new adaptive statistical iterative reconstruction (ASiR-V) in comparison to ASiR. METHODS:A water phantom was acquired with common clinical scanning parameters, at five different levels of CTDIvol . Images were reconstructed with different kernels (STD, SOFT, and BONE...

journal_title：Journal of applied clinical medical physics

authors： De Marco P,Origgi D

更新日期：2018-03-01 00:00:00

abstract：:We investigate the sensitivity of IMRT commissioning using the TG-119 C-shape phantom and credentialing with the IROC head and neck phantom to treatment planning system commissioning errors. We introduced errors into the various aspects of the commissioning process for a 6X photon energy modeled using the analytical a...

journal_title：Journal of applied clinical medical physics

authors： McVicker D,Yin FF,Adamson JD

更新日期：2016-01-08 00:00:00

abstract：INTRODUCTION:The purpose of this study was to present the optimization process of CT parameters to reduce patient exposure during bone SPECT/CT without affecting the quality of SPECT images with attenuation correction (AC). MATERIAL AND METHODS:A fillable phantom reflecting realistic bone scintigraphy conditions was d...

journal_title：Journal of applied clinical medical physics

authors： Tulik M,Tulik P,Kowalska T

更新日期：2020-10-27 00:00:00

abstract：:A microchamber, PTW Pinpoint 31006, was used to measure transverse beam profiles for an Elekta Gamma Knife, Model B, and compared with profiles measured with film dosimetry. The microchamber sensitive volume has a diameter of 2 mm, which is smaller than the gamma knife beams, and a length of 5 mm. The chamber was moun...

journal_title：Journal of applied clinical medical physics

authors： Bank MI

更新日期：2002-01-01 00:00:00

abstract：:The aim of this study is to compare the dosimetric characteristics of robotic and conventional linac-based SBRT techniques for lung cancer, and to provide planning guidance for each modality. Eight patients who received linac-based SBRT were retrospectively included in this study. A dose of 60 Gy given in three fracti...

journal_title：Journal of applied clinical medical physics

authors： Ding C,Chang CH,Haslam J,Timmerman R,Solberg T

更新日期：2010-06-29 00:00:00

abstract：PURPOSE:The purpose of this study was to introduce a new algorithm for automated measurement of the modulation transfer function (MTF) using an edge of a readily available phantom and to evaluate the effect of reconstruction filter and field of view (FOV) on the spatial resolution in the CT images. METHODS:Our automat...

journal_title：Journal of applied clinical medical physics

authors： Anam C,Fujibuchi T,Budi WS,Haryanto F,Dougherty G

更新日期：2018-11-01 00:00:00

abstract：:This work introduces a new technology for electron intensity modulation, which uses small area island blocks within the collimating aperture and small area island apertures in the collimating insert. Due to multiple Coulomb scattering, electrons contribute dose under island blocks and lateral to island apertures. By s...

journal_title：Journal of applied clinical medical physics

authors： Hogstrom KR,Carver RL,Chambers EL,Erhart K

更新日期：2017-11-01 00:00:00

abstract：:In Winston-Lutz (WL) tests, the isocenter of a linear accelerator (linac) is determined as the intersection of radiation central axes (CAX) from multiple gantry, collimator, and couch angles. It is well known that the CAX can wobble due to mechanical imperfections of the linac. Previous studies suggested that the wobb...

journal_title：Journal of applied clinical medical physics

authors： Du W,Johnson JL,Jiang W,Kudchadker RJ

更新日期：2016-01-08 00:00:00

abstract：:Endorectal balloons (ERBs) are routinely used in prostate proton radiation therapy to immobilize the prostate and spare the rectal wall. Rectal gas can distend the rectum and displace the prostate even in the presence of ERBs. The purpose of this work was to quantify the effects an ERB with a passive gas release condu...

journal_title：Journal of applied clinical medical physics

authors： Wootton LS,Kudchadker RJ,Beddar AS,Lee AK

更新日期：2012-09-06 00:00:00

abstract：:Detection and accurate quantification of treatment delivery errors is important in radiation therapy. This study aims to evaluate the accuracy of DVH based QA in quantifying delivery errors. Eighteen previously treated VMAT plans (prostate, H&N, and brain) were randomly chosen for this study. Conventional IMRT deliver...

journal_title：Journal of applied clinical medical physics

authors： Ma T,Podgorsak MB,Kumaraswamy LK

更新日期：2016-09-08 00:00:00