Medical applications of synchrotron radiation.

abstract：:In brachytherapy, plans are routinely calculated using the AAPM TG43 formalism which considers the patient as a simple water object. An accurate modeling of the physical processes considering patient heterogeneity using Monte Carlo simulation (MCS) methods is currently too time-consuming and computationally demanding ...

journal_title：Physics in medicine and biology

authors： Lemaréchal Y,Bert J,Falconnet C,Després P,Valeri A,Schick U,Pradier O,Garcia MP,Boussion N,Visvikis D

更新日期：2015-07-07 00:00:00

abstract：:Burst-tone focused ultrasound exposure in the presence of microbubbles has been demonstrated to be effective at inducing temporal and local opening of the blood-brain barrier (BBB), which promises significant clinical potential to deliver therapeutic molecules into the central nervous system (CNS). Traditional contras...

journal_title：Physics in medicine and biology

authors： Tsai CH,Zhang JW,Liao YY,Liu HL

更新日期：2016-04-07 00:00:00

abstract：:The objective in cancer radiotherapy is to maximize tumor-kill while limiting toxic effects of radiation dose on nearby organs-at-risk (OAR). Given a fixed number of treatment sessions, planners thus face the problem of finding a dosing sequence that achieves this goal. This is called the fractionation problem, and ha...

journal_title：Physics in medicine and biology

authors： Ghate A

更新日期：2020-09-16 00:00:00

abstract：:Values of W (the mean energy required to create an ion pair when a charged particle is stopped in a gas) are needed in radiation dosimetry to convert ionisation chamber current readings to absorbed dose. For neutron dosimetry the most important W values are those for protons, and this paper describes absolute measurem...

journal_title：Physics in medicine and biology

authors： Thomas DJ,Burke M

更新日期：1985-11-01 00:00:00

abstract：:Fractional flow reserve (FFR) provides an objective physiological evaluation of stenosis severity. A technique that can measure FFR using only angiographic images would be a valuable tool in the cardiac catheterization laboratory. To perform this, the diseased blood flow can be measured with a first pass distribution ...

journal_title：Physics in medicine and biology

authors： Wong JT,Molloi S

更新日期：2008-07-21 00:00:00

abstract：:The purpose of this paper is to evaluate the ability of a prototype Compton camera (CC) to measure prompt gamma rays (PG) emitted during delivery of clinical proton pencil beams for prompt gamma imaging (PGI) as a means of providing in vivo verification of the delivered proton radiotherapy beams. A water phantom was i...

journal_title：Physics in medicine and biology

authors： Polf JC,Avery S,Mackin DS,Beddar S

更新日期：2015-09-21 00:00:00

abstract：:A novel approach to read out radiochromic film was introduced recently by the manufacturer of GafChromic film. In this study, the performance of this triple-channel film dosimetry method was compared against the conventional single-red-channel film dosimetry procedure, with and without inclusion of a pre-irradiation (...

journal_title：Physics in medicine and biology

authors： van Hoof SJ,Granton PV,Landry G,Podesta M,Verhaegen F

更新日期：2012-07-07 00:00:00

abstract：:Ultrasonic speed of propagation and attenuation were investigated as a function of absorbed radiation dose in PAG and MAGIC polymer gel dosimeters. Both PAG and MAGIC gel dosimeters displayed a dependence of ultrasonic parameters on absorbed dose with attenuation displaying significant changes in the dose range invest...

journal_title：Physics in medicine and biology

authors： Mather ML,De Deene Y,Whittaker AK,Simon GP,Rutgers R,Baldock C

更新日期：2002-12-21 00:00:00

abstract：:Identification of prostate gold fiducial markers in magnetic resonance imaging (MRI) images is challenging when CT images are not available, due to misclassifications from intra-prostatic calcifications. It is also a time consuming task and automated identification methods have been suggested as an improvement for bot...

journal_title：Physics in medicine and biology

authors： Gustafsson CJ,Swärd J,Adalbjörnsson SI,Jakobsson A,Olsson LE

更新日期：2020-11-12 00:00:00

abstract：:The aim of this study is to determine the impact of longitudinal micro-CT imaging on the growth of B16F1 tumours in C57BL/6 mice. Sixty mice received 2 × 10(5) B16F1 cells subcutaneously in the hind flank and were divided into control (no scan), 'low-dose' (80 kVp, 70 mA, 8 s, 0.07 Gy), 'medium-dose' (80 kVp, 50 mA, 3...

journal_title：Physics in medicine and biology

authors： Foster WK,Ford NL

更新日期：2011-01-21 00:00:00

abstract：:An original method for the analysis of oscillations of cutaneous blood flow has been developed, which makes use of laser Doppler flowmetry (LDF) data and is based on the continuous wavelet transform and adaptive wavelet theory. The potential of the method has been demonstrated in experiments with the response of micro...

journal_title：Physics in medicine and biology

authors： Tankanag A,Chemeris N

更新日期：2008-11-07 00:00:00

abstract：:Physical properties of a position-sensitive camera for the analysis of biodistributions of gamma- and beta-emitting radiopharmaceuticals in small animals have been studied, in order to achieve optimal operating conditions. The camera consisted of a highly segmented yttrium-aluminate perovskite (YAP) scintillator, coup...

journal_title：Physics in medicine and biology

authors： Uzunov N,Bello M,Boccaccio P,Moschini G,Baldazzi G,Bollini D,de Notaristefani F,Mazzi U,Riondato M

更新日期：2005-02-07 00:00:00

abstract：:A rotary positron-emission computed tomography system has been proposed in which detectors are mounted unequally spaced on a ring, so as to provide fine and uniform linear sampling during a 360 degree rotation of the ring around its centre. The usefulness of a simple iterative method for searching for a suitable arran...

journal_title：Physics in medicine and biology

authors： Yamamoto M

更新日期：1981-05-01 00:00:00

abstract：:Reference dosimetry of photon fields is a well-established subject and currently available protocols (such as the IAEA TRS-398 and AAPM TG-51) provide methods for converting the ionization chamber (IC) reading into dose to water, provided reference conditions of charged particle equilibrium (CPE) are fulfilled. But th...

journal_title：Physics in medicine and biology

authors： Pena J,Sánchez-Doblado F,Capote R,Terrón JA,Gómez F

更新日期：2006-03-21 00:00:00

abstract：:In x-ray based imaging of the breast, contrast between fibroglandular (Fg) tissue and adipose (Ad) tissue is a source of anatomic noise. The goal of this work was to validate by simulation and experiment a mathematical framework for modelling the Fg component of anatomic noise in digital mammograpy (DM) and dual-energ...

journal_title：Physics in medicine and biology

authors： Tanguay J,Lalonde R,Bjarnason TA,Yang CJ

更新日期：2019-10-23 00:00:00

abstract：:This paper presents a computer simulation of photon interaction with collimator septa, which allows the point spread function of scintillation camera collimators to be calculated. The method simulates photon attenuation along their propagation direction in a determinist way. Using this simulation, the spatial resoluti...

journal_title：Physics in medicine and biology

authors： Gantet P,Esquerré JP,Danet B,Guiraud R

更新日期：1990-05-01 00:00:00

abstract：:Automatic tube current modulation (TCM) is used in modern CT devices. This is implemented in the numerical calculation of dose conversion coefficients for CT examinations. For four models of adults, the female and male reference models of ICRP and ICRU and a lighter and a heavier female model, dose conversion coeffici...

journal_title：Physics in medicine and biology

authors： Schlattl H,Zankl M,Becker J,Hoeschen C

更新日期：2010-10-21 00:00:00

abstract：:Intensive computation time is required to simulate images of electronic portal imaging device (EPID) using Monte Carlo (MC) technique, limiting the development of applications associated with EPID, such as mega-voltage cone-beam computed tomography (MV-CBCT). In this study, a fast, accurate simulation strategy for MV-...

journal_title：Physics in medicine and biology

authors： Shi M,Myronakis M,Jacobson M,Lehmann M,Ferguson D,Baturin P,Huber P,Fueglistaller R,Harris T,Lozano IV,Williams C,Morf D,Berbeco RI

更新日期：2020-07-06 00:00:00

abstract：:An iterative Bayesian reconstruction algorithm for limited view angle tomography, or ectomography, based on the three-dimensional total variation (TV) norm has been developed. The TV norm has been described in the literature as a method for reducing noise in two-dimensional images while preserving edges, without intro...

journal_title：Physics in medicine and biology

authors： Persson M,Bone D,Elmqvist H

更新日期：2001-03-01 00:00:00

abstract：:The authors have developed an apparatus able to generate ID intensity-modulated beams, using only one moving absorber within the irradiation field. A procedure for deriving optimized absorber-speed profiles in order to produce the desired fluence/dose profiles has been suggested. Experimental tests show that the syste...

journal_title：Physics in medicine and biology

authors： Fiorino C,Lev A,Fusca M,Cattaneo GM,Rudello F,Calandrino R

更新日期：1995-02-01 00:00:00

abstract：:Ultraviolet (UV) treatment dose is determined by the length of time that a patient spends in a phototherapy cabin. The output from UV fluorescent lamps declines with use and a method is needed to compensate for the change in irradiance and to identify and replace any lamps that fail. The decline in lamp output with ag...

journal_title：Physics in medicine and biology

authors： Amatiello H,Martin CJ

更新日期：2006-01-21 00:00:00

abstract：:The advent of real-time ultrasound in the 1970s, together with a growing interest in tissue characterization, led to a number of investigators using the nature of tissue motion to distinguish healthy from diseased tissue. Our group at the (then) Ultrasonics Institute demonstrated the use of phase methods for detecting...

journal_title：Physics in medicine and biology

authors： Wilson LS,Robinson DE,Dadd MJ

更新日期：2000-06-01 00:00:00

abstract：:Statistically based iterative image reconstruction methods have been developed for emission tomography. One important component in iterative image reconstruction is the system matrix, which defines the mapping from the image space to the data space. Several groups have demonstrated that an accurate system matrix can i...

journal_title：Physics in medicine and biology

authors： Qi J,Huesman RH

更新日期：2005-07-21 00:00:00

abstract：:Numerous studies of early-stage breast cancer treated with breast conserving surgery (BCS) and radiotherapy (RT) have been published in recent years. Both external beam radiotherapy (EBRT) and/or brachytherapy (BT) with different fractionation schemes are currently used. The present RT practice is largely based on emp...

journal_title：Physics in medicine and biology

authors： Guerrero M,Li XA

更新日期：2003-10-21 00:00:00

abstract：:Magnetic resonance imaging is effective for non-invasive detection of myocardial diseases by extracellular volume fraction (ECV) estimation. A new methodology for T1 and ECV mapping is tested in this work, comparing results with other well-consolidated methods. The associated level of uncertainty for data was also est...

journal_title：Physics in medicine and biology

authors： Borrazzo C,Pacilio M,Galea N,Preziosi E,Carnì M,Francone M,Catalano C,Carbone I

更新日期：2019-02-11 00:00:00

abstract：:As automation in radiation oncology becomes more common, it is important to determine which algorithms are equivalent for a given workflow. Often, algorithm comparisons are performed in isolation; however, clinical context can provide valuable insight into the importance of algorithm features and error magnification i...

journal_title：Physics in medicine and biology

authors： Weppler S,Schinkel C,Kirkby C,Smith W

更新日期：2020-09-28 00:00:00

abstract：:Cone-beam computed tomography (CBCT) has been clinically used to verify patient position and to localize the target of treatment in image-guided radiation therapy (IGRT). However, when the chest and the upper abdomen are scanned, respiratory-induced motion blurring limits the utility of CBCT. In order to mitigate this...

journal_title：Physics in medicine and biology

authors： Leng S,Tang J,Zambelli J,Nett B,Tolakanahalli R,Chen GH

更新日期：2008-10-21 00:00:00

abstract：:Magnetic resonance imaging (MRI) may be used to image three-dimensional dose distributions of ionizing radiation in tissue equivalent gels infused with ferrous sulphate solutions, commonly known as Fricke gels. In this technique, ferrous (Fe2+) ions are oxidized to ferric (Fe3+) ions by free radicals produced by ioniz...

journal_title：Physics in medicine and biology

authors： Harris PJ,Piercy A,Baldock C

更新日期：1996-09-01 00:00:00

abstract：:Plutonium-239 and americium-241 were administered to adult hamsters in various chemical forms and their absorption from the gut was measured. The results have been compared with published data on other species in order to derive values for the estimated absorption of these actinides in man. On the basis of current kno...

journal_title：Physics in medicine and biology

authors： Stather JW,Harrison JD,Rodwell P,David AJ

更新日期：1979-03-01 00:00:00

abstract：:For the first time the absolute photon mass energy-absorption coefficient of air in the energy range of 10 to 60 keV has been measured with relative standard uncertainties below 1%, considerably smaller than those of up to 2% assumed for calculated data. For monochromatized synchrotron radiation from the electron stor...

journal_title：Physics in medicine and biology

authors： Buhr H,Büermann L,Gerlach M,Krumrey M,Rabus H

更新日期：2012-12-21 00:00:00