SU-E-T-573: Quality and Deliverability of Intensity Modulated Neutron Radiotherapy (IMNRT) Plans.

abstract：:A formulation of the single energy photon transport problem is cast in the form of a series of convolutions over the primary fluence distribution with invariant kernels. A method is developed for compensating for the variant intervoxel attenuation in the scattered dose distribution by means of an invariant correction ...

journal_title：Medical physics

authors： Boyer AL,Mok EC

更新日期：1986-07-01 00:00:00

abstract：PURPOSE:Most clinically deployed strategies for respiratory motion management in lung radiotherapy (e.g., gating and tracking) use external markers that serve as surrogates for tumor motion. However, typical lung phantoms used to validate these strategies are based on a rigid exterior and a rigid or a deformable-interi...

journal_title：Medical physics

authors： Cheung Y,Sawant A

更新日期：2015-05-01 00:00:00

abstract：PURPOSE:The paper presents a complete computer-aided detection (CAD) system for the detection of lung nodules in computed tomography images. A new mixed feature selection and classification methodology is applied for the first time on a difficult medical image analysis problem. METHODS:The CAD system was trained and t...

journal_title：Medical physics

authors： Tan M,Deklerck R,Jansen B,Bister M,Cornelis J

更新日期：2011-10-01 00:00:00

abstract：PURPOSE:Results about the feasibility of a method for quasi real time in vivo dosimetry (IVD) at the isocenter point for volumetric modulated arc therapy (VMAT) are here reported. The method is based on correlations between the EPID signal and the dose on the beam central axis. Moreover, the γ-analysis of EPID images w...

journal_title：Medical physics

authors： Fidanzio A,Porcelli A,Azario L,Greco F,Cilla S,Grusio M,Balducci M,Valentini V,Piermattei A

更新日期：2014-06-01 00:00:00

abstract：PURPOSE:Motion is a major confound of image quality in MRI. A method of retrospectively correcting the effects of rotations and translations on the acquired k-space data is presented. METHODS:In two phantom experiments of well-controlled translation and rotation, two MRI-compatible infrared cameras recorded motion dat...

journal_title：Medical physics

authors： Marxen M,Marmurek J,Baker N,Graham SJ

更新日期：2009-12-01 00:00:00

abstract：:A new approach to the calculation of the x-ray spectrum emerging from an x-ray tube is proposed. Theoretical results for the bremsstrahlung cross section appearing in the literature are summarized. Four different treatments of electron penetration, based on the work presented in Part I, are then used to generate brems...

journal_title：Medical physics

authors： Poludniowski GG

更新日期：2007-06-01 00:00:00

abstract：PURPOSE:To quantify detector perturbation effects in megavoltage small photon fields and support the theoretical explanation on the nature of quality correction factors in these conditions. METHODS:In this second paper, a modern approach to radiation dosimetry is defined for any detector and applied to small photon fi...

journal_title：Medical physics

authors： Bouchard H,Kamio Y,Palmans H,Seuntjens J,Duane S

更新日期：2015-10-01 00:00:00

abstract：:A commercial optical system developed by Solid Photography, Inc., has been used to generate precise paraffin--polyethylene tissue compensators. A program with the objective of constructing a medical facility has been undertaken to access patient topology for treatment planning, tissue-compensator fabrication, and pati...

journal_title：Medical physics

authors： Lerch IA,Barish RJ,Stern H

更新日期：1978-11-01 00:00:00

abstract：:As a potentially important technology for medical x-ray computed tomography (CT), lambda tomography (LT) is to reconstruct a gradient-like image only from local projection data. Based on our recently derived exact fan-beam LT formula, [H. Y. Gu and G. Wang, Int. J. Biomed. Imaging 2006(1), 1-9 (2006)] here we propose ...

journal_title：Medical physics

authors： Yu H,Ye Y,Wang G

更新日期：2006-10-01 00:00:00

abstract：:The use of Kumakhov capillary optics will significantly enhance the performance of near-monochromatic, Compton backscattered x-ray programs. The Vanderbilt University Medical Free-Electron Laser Center is developing the capability to create these tunable x rays for medical imaging. The present transport has only refle...

journal_title：Medical physics

authors： Tompkins PA,Abreu CC,Carroll FE,Xiao QF,MacDonald CA

更新日期：1994-11-01 00:00:00

abstract：:Treatment planning for brachytherapy requires the acquisition of geometrical information of the implant applicator and the patient anatomy. This is typically done using a simulator or a computed tomography scanner. In this study, we present a different method by which orthogonal images from a C-arm fluoroscopic machin...

journal_title：Medical physics

authors： Liu L,Bassano DA,Prasad SC,Keshler BL,Hahn SS

更新日期：2003-09-01 00:00:00

abstract：:The Anisotropic Analytical Algorithm (AAA) of the Varian Eclipse treatment planning system calculates absolute dose for a variety of beam settings including those with an enhanced dynamic wedge (EDW). This algorithm has gone through a number of version updates since it was first released in July 2005. Previous version...

journal_title：Medical physics

authors： Salomons G,Kerr A,Mei X,Patel D

更新日期：2008-07-01 00:00:00

abstract：PURPOSE:To investigate using 3D γ analysis for IMRT and VMAT QA. METHODS:We explored and studied 3D γ-analysis by comparing TPS computed and EPID back-projection reconstructed doses in patient's CT images. Two 3D γ quantities, γ(PTV) and γ(10), were proposed and studied for evaluating the QA results, and compared to 2...

journal_title：Medical physics

authors： Wu C,Hosier KE,Beck KE,Radevic MB,Lehmann J,Zhang HH,Kroner A,Dutton SC,Rosenthal SA,Bareng JK,Logsdon MD,Asche DR

更新日期：2012-06-01 00:00:00

abstract：PURPOSE:To determine the feasibility and potential utility of cone beam CT on breast biopsies. METHODS:CBCT simulations were done with a setup which emulates an MX-20 digital specimen radiography system (Faxitron X-Ray Corporation, Chicago, IL), albeit a DQE = 1 was assumed. The phantom consisted of a 5mm diameter cyl...

journal_title：Medical physics

authors： Laamanen C,LeClair R

更新日期：2012-07-01 00:00:00

abstract：PURPOSE:The aim of this study was to develop a dose calculation method which is applicable to the interseed attenuation and the geometry lacking the equilibrium radiation scatter conditions in brachytherapy. METHODS:The dose obtained from measurement with a radiophotoluminescent glass rod dosimeter (GRD) was compared ...

journal_title：Medical physics

authors： Tanaka K,Tateoka K,Asanuma O,Kamo K,Bengua G,Sato K,Ueda T,Takeda H,Takagi M,Hareyama M,Takada J

更新日期：2011-06-01 00:00:00

abstract：:Recently, new imaging modalities based on the detection of weak phase perturbations effects, among which are phase contrast and diffraction imaging, have been developed by several researchers. Due to their high sensitivity to weakly absorbing details, these techniques seem to be very promising for applications in the ...

journal_title：Medical physics

authors： Olivo A,Arfelli F,Cantatore G,Longo R,Menk RH,Pani S,Prest M,Poropat P,Rigon L,Tromba G,Vallazza E,Castelli E

更新日期：2001-08-01 00:00:00

abstract：PURPOSE:Manual delineation of head and neck (H&N) organ-at-risk (OAR) structures for radiation therapy planning is time consuming and highly variable. Therefore, we developed a dynamic multiatlas selection-based approach for fast and reproducible segmentation. METHODS:Our approach dynamically selects and weights the a...

journal_title：Medical physics

authors： Haq R,Berry SL,Deasy JO,Hunt M,Veeraraghavan H

更新日期：2019-12-01 00:00:00

abstract：PURPOSE:To design volume-specific breast phantoms from breast CT (bCT) data sets and estimate the associated normalized mean glandular dose coefficients for breast CT using Monte Carlo methods. METHODS:A large cohort of bCT data sets (N = 215) was used to evaluate breast volume into quintiles (plus the top 5%). The av...

journal_title：Medical physics

authors： Hernandez AM,Boone JM

更新日期：2017-10-01 00:00:00

abstract：PURPOSE:Magnetic resonance imaging (MRI) is increasingly used for radiotherapy target delineation, image guidance, and treatment response monitoring. Recent studies have shown that an entire external x-ray radiotherapy treatment planning (RTP) workflow for brain tumor or prostate cancer patients based only on MRI refer...

journal_title：Medical physics

authors： Koivula L,Wee L,Korhonen J

更新日期：2016-08-01 00:00:00

abstract：:The authors present an alternative approach to inverse planning optimization and apply it to volumetric modulated are therapy (VMAT) in one rotation with a prior knowledge about the type of leaf motions. The optimization is based on the projection theorem in inner product spaces. MLC motion is directly considered in t...

journal_title：Medical physics

authors： Hoegele W,Loeschel R,Zygmanski P

更新日期：2009-08-01 00:00:00

abstract：:Setting up and maintaining video display monitors properly will help to reduce display variation and improve overall presentation of the radiological image. Display monitor gray-scale characteristics were examined using the SMPTE test pattern. This test pattern may be used as a standard for adjusting brightness and co...

journal_title：Medical physics

authors： Nawfel RD,Chan KH,Wagenaar DJ,Judy PF

更新日期：1992-05-01 00:00:00

abstract：:Pixel size is of great interest in the flat-panel detector design because of its potential impact on image quality. In the particular case of angiographic x-ray fluoroscopy, small pixels are required in order to adequately visualize interventional devices such as guidewires and stents which have wire diameters as smal...

journal_title：Medical physics

authors： Jiang Y,Wilson DL

更新日期：2006-03-01 00:00:00

abstract：PURPOSE:Although small animal image-guided radiotherapy (SA-IGRT) systems are used increasingly in preclinical research, tools for performing routine quality assurance (QA) have not been optimized and are not readily available. Robust, efficient, and reliable QA tools are needed to ensure the accuracy and reproducibili...

journal_title：Medical physics

authors： Anvari A,Poirier Y,Sawant A

更新日期：2018-07-01 00:00:00

abstract：:The NSD equation, D = 1850 x T0.11 x N0.24, is a celebrated transmogrification of Cohen's two well-known collations of data on response to clinical irradiations (3 degrees erythema and 0.90 ablation of skin cancer) in which the relation of D and T is fixed by the data selected by Cohen and the additional constraint th...

journal_title：Medical physics

authors： Herbert DE Jr

更新日期：1981-11-01 00:00:00

abstract：:A new beam line for radiotherapy and radiosurgery with accelerated helium-ion beams has been set up at the Bevalac. The new treatment room has been equipped with a very precise patient positioner in order to utilize the superior dose localization properties of light-ion beams. The beam spreading and shaping system is ...

journal_title：Medical physics

authors： Ludewigt BA,Chu WT,Phillips MH,Renner TR

更新日期：1991-01-01 00:00:00

abstract：PURPOSE:Quantitative SPECT imaging is limited by many factors, including penetration of high energy photons through the collimator. Even small peaks of high energy yield extensive contamination in the photopeak energy window. Rotating slat collimators typically offer a 40- to 50-fold increase in geometric detection eff...

journal_title：Medical physics

authors： Van Holen R,Staelens S,Vandenberghe S

更新日期：2009-09-01 00:00:00

abstract：PURPOSE:To characterize the radiation dose and three-dimensional (3D) imaging performance of a recently developed mobile, isocentric C-arm equipped with a flat-panel detector (FPD) for intraoperative cone-beam computed tomography (CBCT) (Cios Spin 3D, Siemens Healthineers) and to identify potential improvements in 3D i...

journal_title：Medical physics

authors： Sheth NM,De Silva T,Uneri A,Ketcha M,Han R,Vijayan R,Osgood GM,Siewerdsen JH

更新日期：2020-03-01 00:00:00

abstract：:In this investigation, five experimental data sets are used to evaluate the ability of the EGSnrc Monte Carlo code to calculate the change in chamber response associated with changes in wall material and cavity dimension at 60Co energies. Calculations of the ratios of response per unit mass of air as a function of cav...

journal_title：Medical physics

authors： La Russa DJ,Rogers DW

更新日期：2008-12-01 00:00:00

abstract：:An investigation was performed of the changes in image quality and patient dose as a result of increasing filtration for fluoroscopy performed under automatic brightness control. Filtration was added either at the x-ray tube housing (i.e., scatter-free geometry) or adjacent to a tissue equivalent phantom simulating th...

journal_title：Medical physics

authors： Geiser WR,Huda W,Gkanatsios NA

更新日期：1997-03-01 00:00:00

abstract：:The assessment of differential left and right lung function is important for patients under consideration for lung resection procedures such as single lung transplantation. We developed an automated, knowledge-based segmentation algorithm for purposes of deriving functional information from dynamic computed tomography...

journal_title：Medical physics

authors： Brown MS,Goldin JG,McNitt-Gray MF,Greaser LE,Sapra A,Li KT,Sayre JW,Martin K,Aberle DR

更新日期：2000-03-01 00:00:00