Photon and electron response of silicon-diode neutron detectors.

abstract：PURPOSE:New preclinical image-guided irradiators and treatment planning systems represent a huge progress in radiobiology. Nevertheless, quality control of preclinical treatments is not as advanced as in clinical radiotherapy and in vivo dosimetry is less developed. In this study, we evaluate the use of a scintillating...

journal_title：Medical physics

authors： Le Deroff C,Pérès EA,Ledoux X,Toutain J,Frelin-Labalme AM

更新日期：2020-01-01 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:Breast density is a significant breast cancer risk factor. Although various methods are used to estimate breast density, there is no standard measurement for this important factor. The authors are developing a breast density standardization method for use in full field digital mammography (FFDM). The approach c...

journal_title：Medical physics

authors： Heine JJ,Cao K,Beam C

更新日期：2009-12-01 00:00:00

abstract：:Radiographic magnification is often employed in mammography to improve detection of small anatomical details of clinical interest, such as microcalcifications. The image size depends on the conventional magnification factor, on the focal spot size, and on the x-ray angulation. In this paper magnification effects are i...

journal_title：Medical physics

authors： Schiabel H,Ventura A,Frère AF

更新日期：1994-02-01 00:00:00

abstract：PURPOSE:X-ray phase-contrast tomography (PCT) is a rapidly emerging imaging modality for reconstructing estimates of an object's three-dimensional x-ray refractive index distribution. Unlike conventional x-ray computed tomography methods, the statistical properties of the reconstructed images in PCT remain unexplored. ...

journal_title：Medical physics

authors： Chou CY,Anastasio MA

更新日期：2010-01-01 00:00:00

abstract：:The use of magnetic resonance imaging as a readout method for polymer gel dosimetry commonly involves long imaging sessions, particularly when high spatial resolution is required in all three dimensions, for the investigation of dose distributions with steep dose gradients and stringent dose delivery specifications. I...

journal_title：Medical physics

authors： Baras P,Seimenis I,Sandilos P,Vlahos L,Bieganski T,Georgiou E,Pantelis E,Papagiannis P,Sakelliou L

更新日期：2005-11-01 00:00:00

abstract：:A new system of radiation dose mapping based on laser heating of thermoluminescent dosimetric plates (TLDP) has been developed. Application of this technique to intraoperative radiotherapy (IORT) has been investigated. Preliminary results show that TLDP are a possible alternative to radiological films and ionization c...

journal_title：Medical physics

authors： Beteille D,Setzkom R,Prévost H,Dusseau L,Fesquet J,Gasiot J,Muraro S,Delard R,Dubois JB,Ailleres N,Missous O

更新日期：1996-08-01 00:00:00

abstract：:Radiographic image guidance has emerged as the new paradigm for patient positioning, target localization, and external beam alignment in radiotherapy. Although widely varied in modality and method, all radiographic guidance techniques have one thing in common--they can give a significant radiation dose to the patient....

journal_title：Medical physics

authors： Murphy MJ,Balter J,Balter S,BenComo JA Jr,Das IJ,Jiang SB,Ma CM,Olivera GH,Rodebaugh RF,Ruchala KJ,Shirato H,Yin FF

更新日期：2007-10-01 00:00:00

abstract：:The method of magnetic resonance imaging (MRI) was an extension of nuclear magnetic resonance (NMR) spectroscopy that was enabled by computational systems capable of performing the Fast Fourier Transform. Initially, a diverse group of methods were proposed for producing images with NMR, with the multi-slice spin-warp ...

journal_title：Medical physics

authors： Clarke G

更新日期：2012-06-01 00:00:00

abstract：PURPOSE:The purpose of this study is to evaluate the performance of a recently developed benchtop dual cone-beam computed tomography (CBCT) system with two orthogonally placed tube∕detector sets. METHODS:The benchtop dual CBCT system consists of two orthogonally placed 40 × 30 cm flat-panel detectors and two conventio...

journal_title：Medical physics

authors： Li H,Giles W,Bowsher J,Yin FF

更新日期：2013-02-01 00:00:00

abstract：PURPOSE:To estimate and correct for the volume averaging effect which results from the intra-chamber dose gradients when a Farmer ionization chamber (IC) is used for reference dosimetry in flattening-filter-free (FFF) MV photon beams. METHODS:An intra-chamber dose gradients correction factor (kicdg) to the charge read...

journal_title：Medical physics

authors： Ruggieri R,Naccarato S,Stavrev P,Stavreva N,Pasetto S,Salamone I,Alongi F

更新日期：2016-08-01 00:00:00

abstract：:Lag in fluoroscopic systems introduces a frame-averaging effect that reduces measurements of image noise and incorrectly inflates measurements of the detective quantum efficiency (DQE). A correction can be implemented based on measurements of the temporal modulation transfer function (MTF). We introduce a method of me...

journal_title：Medical physics

authors： Friedman SN,Cunningham IA

更新日期：2008-06-01 00:00:00

abstract：PURPOSE:Automated 3D breast ultrasound (ABUS) has gained interest in breast imaging. Especially for screening women with dense breasts, ABUS appears to be beneficial. However, since the amount of data generated is large, the risk of oversight errors is substantial. Computer aided detection (CADe) may be used as a secon...

journal_title：Medical physics

authors： Tan T,Mordang JJ,van Zelst J,Grivegnée A,Gubern-Mérida A,Melendez J,Mann RM,Zhang W,Platel B,Karssemeijer N

更新日期：2015-04-01 00:00:00

abstract：:The hybrid algorithms developed recently for the reconstruction of fan-beam images possess computational and noise properties superior to those of the fan-beam filtered backprojection (FFBP) algorithm. However, the hybrid algorithms cannot be applied directly to a halfscan fan-beam sinogram because they require knowle...

journal_title：Medical physics

authors： Pan X

更新日期：2000-09-01 00:00:00

abstract：:The large variation of x-ray fluence at the detector in cone-beam CT (CBCT) poses a significant challenge to detectors' limited dynamic range, resulting in the loss of skinline as well as reduction of CT number accuracy, contrast-to-noise ratio, and image uniformity. The authors investigate the performance of a bowtie...

journal_title：Medical physics

authors： Mail N,Moseley DJ,Siewerdsen JH,Jaffray DA

更新日期：2009-01-01 00:00:00

abstract：PURPOSE:The impact and the development of aneurysms depend to a significant degree on the exchange of liquid between the regular vessel and the pathological extension. A better understanding of this process will lead to improved prediction capabilities. The aim of the current study was to investigate fluid-exchange in ...

journal_title：Medical physics

authors： Edelhoff D,Walczak L,Frank F,Heil M,Schmitz I,Weichert F,Suter D

更新日期：2015-10-01 00:00:00

abstract：:When a catheter is inserted through an artery, the wall shear stress increases and the secondary flow exhibits an increased number of instantaneous vortices. These effects become more evident when the annular gap between the catheter and the artery becomes more narrow. Accordingly it is suggested that these factors ma...

journal_title：Medical physics

authors： Karahalios GT

更新日期：1990-09-01 00:00:00

abstract：PURPOSE:High-Z material in computed tomography (CT) yields metal artifacts that degrade image quality and may cause substantial errors in dose calculation. This study couples a metal artifact reduction (MAR) algorithm with enhanced 16-bit depth (vs standard 12-bit) to quantify potential gains in image quality and dosim...

journal_title：Medical physics

authors： Glide-Hurst C,Chen D,Zhong H,Chetty IJ

更新日期：2013-06-01 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：PURPOSE:Intensity modulated proton therapy (IMPT) is sensitive to errors, mainly due to high stopping power dependency and steep beam dose gradients. Conventional margins are often insufficient to ensure robustness of treatment plans. In this article, a method is developed that takes the uncertainties into account duri...

journal_title：Medical physics

authors： Fredriksson A,Forsgren A,Hårdemark B

更新日期：2011-03-01 00:00:00

abstract：PURPOSE:To characterize the modulation transfer function (MTF) of proton/carbon radiography using Monte Carlo simulations. To assess the spatial resolution of proton/carbon radiographic imaging. METHODS:A phantom was specifically modeled with inserts composed of two materials with three different densities of bone and...

journal_title：Medical physics

authors： Seco J,Oumano M,Depauw N,Dias MF,Teixeira RP,Spadea MF

更新日期：2013-09-01 00:00:00

abstract：:Surgical guidance with fluorescence has been demonstrated in individual clinical trials for decades, but the scientific and commercial conditions exist today for a dramatic increase in clinical value. In the past decade, increased use of indocyanine green based visualization of vascular flow, biliary function, and tis...

journal_title：Medical physics

authors： Pogue BW,Paulsen KD,Samkoe KS,Elliott JT,Hasan T,Strong TV,Draney DR,Feldwisch J

更新日期：2016-06-01 00:00:00

abstract：:We present a technique for semiautomated segmentation of human prostates using suprapubic ultrasound (US) images. In this approach, a speckle reducing anisotropic diffusion (SRAD) is applied to enhance the images and the instantaneous coefficient of variation (ICOV) is utilized for edge detection. Segmentation is acco...

journal_title：Medical physics

authors： Yu Y,Molloy JA,Acton ST

更新日期：2004-12-01 00:00:00

abstract：:This paper examines the distributions of the SAR (specific absorption rate) ratio and temperature elevation when an ultrasound beam propagates through the interface of muscle and bone. This interface is regarded as a flat boundary to partition the energy of the ultrasound beam, and the analytical solution of temperatu...

journal_title：Medical physics

authors： Lin WL,Liauh CT,Chen YY,Liu HC,Shieh MJ

更新日期：2000-05-01 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：PURPOSE:Multiple commercial, open-source, and academic software tools exist for objective quantification of lung density in computed tomography (CT) images. The purpose of this study was to evaluate the intersoftware reproducibility of CT lung density measurements. METHODS:Computed tomography images from 50 participan...

journal_title：Medical physics

authors： Kirby M,Hatt C,Obuchowski N,Humphries SM,Sieren J,Lynch DA,Fain SB,QIBA Lung Density Committee.

更新日期：2020-07-01 00:00:00

abstract：PURPOSE:To evaluate plan quality of a novel MRI-compatible direction modulated brachytherapy (DMBT) tandem applicator using 192 Ir, 60 Co, and 169 Yb HDR brachytherapy sources, for various cervical cancer high-risk clinical target volumes (CTVHR ). MATERIALS AND METHODS:The novel DMBT tandem applicator has six periphe...

journal_title：Medical physics

authors： Safigholi H,Han DY,Mashouf S,Soliman A,Meigooni AS,Owrangi A,Song WY

更新日期：2017-12-01 00:00:00

abstract：PURPOSE:As radiation therapy evolves toward more adaptive techniques, image guidance plays an increasingly important role, not only in patient setup but also in monitoring the delivered dose and adapting the treatment to patient changes. This study aimed to validate a method for evaluation of delivered intensity modula...

journal_title：Medical physics

authors： Moteabbed M,Sharp GC,Wang Y,Trofimov A,Efstathiou JA,Lu HM

更新日期：2015-01-01 00:00:00

abstract：PURPOSE:Pulse pileup occurring at high x-ray fluxes can severely degrade the energy resolution provided by a photon counting detector, which can represent a problem in spectroscopic CT when performing quantitative material discrimination tasks. As the effects of pileup can be most easily seen as a degradation of a dete...

journal_title：Medical physics

authors： Rink K,Oelfke U,Fiederle M,Zuber M,Koenig T

更新日期：2013-10-01 00:00:00

abstract：:Bioluminescent imaging (BLI) of luciferase-expressing cells in live small animals is a powerful technique for investigating tumor growth, metastasis, and specific biological molecular events. Three-dimensional imaging would greatly enhance applications in biomedicine since light emitting cell populations could be unam...

journal_title：Medical physics

authors： Slavine NV,Lewis MA,Richer E,Antich PP

更新日期：2006-01-01 00:00:00