Experimental verification of numerical simulations of cryosurgery with application to computerized planning.

abstract：:The optical properties (absorption and scattering coefficients and the scattering anisotropy factor) were measured in vitro for cartilage, liver, lung, muscle, myocardium, skin, and tumour (colon adenocarcinoma CC 531) at 630, 632.8, 790, 850 and 1064 nm. Rabbits, rats, piglets, goats, and dogs were used to obtain the...

journal_title：Physics in medicine and biology

authors： Beek JF,Blokland P,Posthumus P,Aalders M,Pickering JW,Sterenborg HJ,van Gemert MJ

更新日期：1997-11-01 00:00:00

abstract：:The formulation of intensity modulated radiation therapy (IMRT) planning aspects frequently uses the dose-volume histogram (DVH), whereas plan computations often happen in the more desirable convex IMRT optimization framework. Inspired by a recent publication of Zinchenko et al (2008 Phys. Med. Biol. 53 3231-50), this...

journal_title：Physics in medicine and biology

authors： Kratt K,Scherrer A

更新日期：2009-06-21 00:00:00

abstract：:Results from dielectric studies on the freshwater fish Cyprinus carpio exposed to a sublethal concentration of sodium alkyl benzene sulphonate were compared with those from untreated control fish; recovery from the test solution was also checked. The influence of the anionic detergent on the intracellular matter of fi...

journal_title：Physics in medicine and biology

authors： Bielinska I,Terlecki J

更新日期：1984-05-01 00:00:00

abstract：:In carbon-ion radiotherapy, single-beam delivery each day in alternate directions has been common practice for efficient operation, taking advantage of the Bragg peak and the relative biological effectiveness (RBE) for uniform dose conformation to a tumor. Treatments are usually fractionated and treatment plans are ev...

journal_title：Physics in medicine and biology

authors： Kanematsu N,Inaniwa T

更新日期：2017-02-07 00:00:00

abstract：:We compare two different implementations of a 3D SPECT system model for iterative reconstruction, both of which compensate for non-uniform photon attenuation and depth-dependent system response. One implementation performs fast rotation of images represented using a basis of rectangular voxels, whereas the other repre...

journal_title：Physics in medicine and biology

authors： Yendiki A,Fessler JA

更新日期：2004-06-07 00:00:00

abstract：:The quality of thorax and pelvis transmission scans and therefore of attenuation correction in PET depends on patient thickness and transmission rod source strength. The purpose of the present study was to assess the feasibility of using count-based transmission scans, thereby guaranteeing more consistent image qualit...

journal_title：Physics in medicine and biology

authors： Boellaard R,van Lingen A,van Balen SC,Lammertsma AA

更新日期：2004-02-21 00:00:00

abstract：:Recently, there has been an increased interest in imaging different pulmonary disorders using PET techniques. Previous work has shown, for static PET/CT, that air content in the lung influences reconstructed image values and that it is vital to correct for this 'tissue fraction effect' (TFE). In this paper, we extend ...

journal_title：Physics in medicine and biology

authors： Holman BF,Cuplov V,Millner L,Hutton BF,Maher TM,Groves AM,Thielemans K

更新日期：2015-09-21 00:00:00

abstract：:Imaging technologies that allow non-radiative visualization and quantification of apoptosis have a great potential for assessing therapy response, early diagnosis, and disease monitoring. Magnetic particle imaging (MPI), the direct imaging of magnetic nanoparticles as positive contrast agent and sole signal source, en...

journal_title：Physics in medicine and biology

authors： Liang X,Wang K,Du J,Tian J,Zhang H

更新日期：2020-09-24 00:00:00

abstract：:Several papers have recently addressed the issue of estimating chromophore concentration in optoacoustic imaging (OAI) using multiple wavelengths. The choice of wavelengths obviously affects the accuracy and precision of the estimates. One might assume that the wavelengths that maximize the extinction coefficients of ...

journal_title：Physics in medicine and biology

authors： Modgil D,La Riviére PJ

更新日期：2010-12-07 00:00:00

abstract：:Time-of-flight (TOF) positron emission tomography (PET) technology has recently regained popularity in clinical PET studies for improving image quality and lesion detectability. Using TOF information, the spatial location of annihilation events is confined to a number of image voxels along each line of response, there...

journal_title：Physics in medicine and biology

authors： Mehranian A,Kotasidis F,Zaidi H

更新日期：2016-02-07 00:00:00

abstract：:We report the first experimental soft-tissue phase-contrast tomography results using a conventional x-ray tube source, with a millimeter-sized focal spot. The setup is based on a Talbot-Lau grating interferometer operated at a mean energy of 28 keV. We present three-dimensional ex vivo images of a chicken heart sample...

journal_title：Physics in medicine and biology

authors： Bech M,Jensen TH,Feidenhans'l R,Bunk O,David C,Pfeiffer F

更新日期：2009-05-07 00:00:00

abstract：:This paper reports a theoretical study on the distribution of blood flow in the human cardiovascular system when one or more blood vessels are affected by stenosis. The analysis employs a mathematical model of the entire system based on the finite element method. The arterial-venous network is represented by a large n...

journal_title：Physics in medicine and biology

authors： Sud VK,Srinivasan RS,Charles JB,Bungo MW

更新日期：1993-03-01 00:00:00

abstract：:Multi-atlas segmentation (MAS) has been widely used to automate the delineation of organs at risk (OARs) for radiotherapy. Label fusion is a crucial step in MAS to cope with the segmentation variabilities among multiple atlases. However, most existing label fusion methods do not consider the potential dosimetric impac...

journal_title：Physics in medicine and biology

authors： Chang J,Tian Z,Lu W,Gu X,Chen M,Jiang SB

更新日期：2017-05-07 00:00:00

abstract：:Deformable image registration (DIR) is increasingly used in radiotherapy applications and provides the basis for a previously described model of patient-specific respiratory motion. We examine the accuracy of a DIR algorithm and a motion model with respiration-correlated CT (RCCT) images of software phantom with known...

journal_title：Physics in medicine and biology

authors： Liu F,Hu Y,Zhang Q,Kincaid R,Goodman KA,Mageras GS

更新日期：2012-05-07 00:00:00

abstract：:Two new detectors (0.015 cm3 ion chamber from PTW, 0.6 mm diameter diode from Scanditronix AB) designed specifically for use in small stereotactic fields were compared against similar, more routine, detectors (0.125 cm3 ion chamber, parallel plate chamber, shielded and unshielded diodes and film). Percentage depth dos...

journal_title：Physics in medicine and biology

authors： McKerracher C,Thwaites DI

更新日期：1999-09-01 00:00:00

abstract：:Range verification in proton therapy is a critical quality assurance task. We studied the feasibility of online range verification based on proton-induced acoustic signals, using a bidirectional long-short-term-memory recurrent neural network and various signal processing techniques. Dose distribution of 1D pencil pro...

journal_title：Physics in medicine and biology

authors： Yao S,Hu Z,Zhang X,Lou E,Liang Z,Wang Y,Peng H

更新日期：2020-11-05 00:00:00

abstract：:This paper introduces a method to simultaneously minimize the leaf travel distance and the tongue-and-groove effect for IMRT leaf sequences to be delivered in segmental mode. The basic idea is to add a large enough number of openings through cutting or splitting existing openings for those leaf pairs with openings few...

journal_title：Physics in medicine and biology

authors： Dai J,Que W

更新日期：2004-12-07 00:00:00

abstract：:The electrostimulation excitation threshold of a nerve depends on temporal and frequency parameters of the stimulus. These dependences were investigated in terms of: (1) strength-duration (SD) curve for a single monophasic rectangular pulse, and (2) frequency dependence of the excitation threshold for a continuous sin...

journal_title：Physics in medicine and biology

authors： Šarolić A,Živković Z,Reilly JP

更新日期：2016-06-21 00:00:00

abstract：:Within an epidemiological study regarding the correlation between skin pathologies and personal ultraviolet (UV) exposure due to solar radiation, 14 field campaigns using polysulphone (PS) dosemeters were carried out at three different Italian sites (urban, semi-rural and rural) in every season of the year. A polysulp...

journal_title：Physics in medicine and biology

authors： Casale GR,Borra M,Colosimo A,Colucci M,Militello A,Siani AM,Sisto R

更新日期：2006-09-07 00:00:00

abstract：:This work aims to develop a voxel-level dose prediction framework by integrating distance information between PTV and OARs, as well as image information, into a densely-connected network (DCNN). Firstly, a four-channel feature map, consisting of a PTV image, an OAR image, a CT image, and a distance image, is construct...

journal_title：Physics in medicine and biology

authors： Zhang J,Liu S,Yan H,Li T,Mao R,Liu J

更新日期：2020-10-21 00:00:00

abstract：:This work aims to investigate the dosimetric impact of dental implants on volumetric modulated arc therapy (VMAT) for head-and-neck patients and to evaluate the effectiveness of using the material's electron-density ratio for the correction. An in-house Monte Carlo (MC) code was utilized for the dose calculation to ac...

journal_title：Physics in medicine and biology

authors： Lin MH,Li J,Price RA Jr,Wang L,Lee CC,Ma CM

更新日期：2013-02-21 00:00:00

abstract：:For medical applications of ultrasound inside the brain, it is necessary to understand the relationship between the apparent density of skull bone and its corresponding speed of sound and attenuation coefficient. Although there have been previous studies exploring this phenomenon, there is still a need to extend the m...

journal_title：Physics in medicine and biology

authors： Pichardo S,Sin VW,Hynynen K

更新日期：2011-01-07 00:00:00

abstract：:Dynamic radiation therapy techniques require that the treatment head setup varies in time and space during dose delivery. Examples are leaf motion in intensity modulated x-ray therapy, modulator wheel rotation in conventional proton therapy and variable magnet settings in proton beam scanning. Consequently, for Monte ...

journal_title：Physics in medicine and biology

authors： Paganetti H

更新日期：2004-03-21 00:00:00

abstract：:A mathematical model has been constructed to simulate the response of cells in vitro to fractionated doses of radiation. The model is capable of describing most of the radiobiological functions that are commonly studied. Input data are measurable cell properties. The details of the model and methods of acquiring the i...

journal_title：Physics in medicine and biology

authors： Niederer J,Cunningham JR

更新日期：1976-09-01 00:00:00

abstract：:In this study we investigate light penetration into skin in order to define the optimal wavelength for the treatment of port wine stains. A two-layer model (epidermis and dermis) is applied with a cylindric tube representing the ectatic blood vessel. Light propagation is calculated by the Monte Carlo method. Values fo...

journal_title：Physics in medicine and biology

authors： Kienle A,Hibst R

更新日期：1995-10-01 00:00:00

abstract：:Positron emission tomography is one of the most mature techniques for monitoring the particles range in hadron therapy, aiming to reduce treatment uncertainties and therefore the extent of safety margins in the treatment plan. In-beam PET monitoring has been already performed using inter-spill and post-irradiation dat...

journal_title：Physics in medicine and biology

authors： Kostara E,Sportelli G,Belcari N,Camarlinghi N,Cerello P,Del Guerra A,Ferrero V,Fiorina E,Giraudo G,Morrocchi M,Pennazio F,Pullia M,Rivetti A,Rolo MD,Rosso V,Wheadon R,Bisogni MG

更新日期：2019-01-21 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：:Automatic cell cycle analysis (DNA histograms) is usually performed with flow cytometry. In cases when only few cells are available, the DNA content has to be measured with a fluorescence microscope combined with sensitive camera systems (SIT, MCP, cooled CCDs) and a frame grabber for image analysis. The fluorescent c...

journal_title：Physics in medicine and biology

authors： Böcker W,Gantenberg HW,Müller WU,Streffer C

更新日期：1996-03-01 00:00:00

abstract：:Refraction contrast of simple objects obtained using diffraction enhanced imaging (DEI) was studied and compared to conventional radiographic contrast. Lucite cylinders and nylon wires were imaged using monochromatic synchrotron radiation at the National Synchrotron Light Source (http://nslsweb. nsls.bnl.gov/nsls/Defa...

journal_title：Physics in medicine and biology

authors： Kiss MZ,Sayers DE,Zhong Z

更新日期：2003-02-07 00:00:00

abstract：:Four-dimensional computed tomography (4D-CT) requires breathing information from the patient, and for this, several systems are available. Testing of these systems, under realistic conditions, requires a phantom with a moving target and an expandable outer contour. An anthropomorphic phantom was developed to simulate ...

journal_title：Physics in medicine and biology

authors： Vásquez AC,Runz A,Echner G,Sroka-Perez G,Karger CP

更新日期：2012-05-07 00:00:00