The biomechanics of simple steatosis and steatohepatitis.

abstract：:The bone suppression technique based on advanced image processing can suppress the conspicuity of bones on chest radiographs, creating soft tissue images obtained by the dual-energy subtraction technique. This study was performed to evaluate the usefulness of bone suppression image processing in image-guided radiation...

journal_title：Physics in medicine and biology

authors： Tanaka R,Sanada S,Sakuta K,Kawashima H

更新日期：2015-05-21 00:00:00

abstract：:Respiratory gating based on external surrogates is performed in many clinics. We have developed a new technique for treatment verification using an electronic portal imaging device (EPID) in cine mode for gated 3D conformal therapy. Implanted radiopaque fiducial markers inside or near the target are required for this ...

journal_title：Physics in medicine and biology

authors： Berbeco RI,Neicu T,Rietzel E,Chen GT,Jiang SB

更新日期：2005-08-21 00:00:00

abstract：:Ultrasound Doppler (UD) velocity measurements are commonly used to quantify blood flow velocities in vivo. The aim of our work was to investigate the accuracy of in vivo spectral Doppler measurements of velocity waveforms. Waveforms were derived from spectral Doppler signals and corrected for intrinsic spectral broade...

journal_title：Physics in medicine and biology

authors： Jiang J,Strother C,Johnson K,Baker S,Consigny D,Wieben O,Zagzebski J

更新日期：2011-03-21 00:00:00

abstract：:The classical Sievert integral method is a valuable tool for dose rate calculations around brachytherapy sources, combining simplicity with reasonable computational times. However, its accuracy in predicting dose rate anisotropy around 192Ir brachytherapy sources has been repeatedly put into question. In this work, we...

journal_title：Physics in medicine and biology

authors： Karaiskos P,Angelopoulos A,Baras P,Rozaki-Mavrouli H,Sandilos P,Vlachos L,Sakelliou L

更新日期：2000-02-01 00:00:00

abstract：:Microbeam radiation therapy (MRT) is a treatment approach in radiation therapy where the treatment field is spatially fractionated into arrays of a few tens of micrometre wide planar beams of unusually high peak doses separated by low dose regions of several hundred micrometre width. In preclinical studies, this treat...

journal_title：Physics in medicine and biology

authors： Debus C,Oelfke U,Bartzsch S

更新日期：2017-10-19 00:00:00

abstract：:A solid dynamic phantom with tissue-like optical properties is presented, which contains seven discrete targets impregnated with thermochromic pigment located at different depths from the surface. Changes in absorption are obtained in response to localized heating of the targets, simulating haemodynamic changes occurr...

journal_title：Physics in medicine and biology

authors： Correia T,Banga A,Everdell NL,Gibson AP,Hebden JC

更新日期：2009-10-21 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：:A dynamic-contrast-enhanced magnetic resonance imaging (DCE-MRI) dataset consists of many imaging frames, often acquired both before and after contrast injection. Due to the length of time spent acquiring images, patient motion is likely and image re-alignment or registration is required before further analysis such a...

journal_title：Physics in medicine and biology

authors： Melbourne A,Hipwell J,Modat M,Mertzanidou T,Huisman H,Ourselin S,Hawkes DJ

更新日期：2011-12-21 00:00:00

abstract：:A method for registering images acquired from a prototype flat panel mobile C-arm, capable of kilovoltage (kV) cone-beam computed tomography (CT), to a linear accelerator (LINAC) isocenter is presented. A calibration procedure is performed which involves locating reflective markers placed on the C-arm and a phantom in...

journal_title：Physics in medicine and biology

authors： Sorensen S,Mitschke M,Solberg T

更新日期：2007-06-21 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：:Protons and carbon ion beams for hadron therapy can be delivered by cyclotrons with a fixed energy. In order to treat patients, an energy degrader along the beam line will be used to match the particle range with the target depth. Fragmentation reactions of carbon ions inside the degrader material could introduce a sm...

journal_title：Physics in medicine and biology

authors： Morone MC,Calabretta L,Cuttone G,Fiorini F

更新日期：2008-11-07 00:00:00

abstract：:We investigate an optimization-based reconstruction, with an emphasis on image-artifact reduction, from data collected in C-arm cone-beam computed tomography (CBCT) employed in image-guided interventional procedures. In the study, an image to be reconstructed is formulated as a solution to a convex optimization progra...

journal_title：Physics in medicine and biology

authors： Xia D,Langan DA,Solomon SB,Zhang Z,Chen B,Lai H,Sidky EY,Pan X

更新日期：2016-10-21 00:00:00

abstract：:In medical imaging different techniques have been developed to gain information from inside a tissue. Optoacoustics is a method to generate tomography pictures of tissue using Q-switched laser pulses. Due to thermal and pressure confinement, a short light pulse generates a pressure distribution inside tissue, which mi...

journal_title：Physics in medicine and biology

authors： Köstli KP,Frenz M,Bebie H,Weber HP

更新日期：2001-07-01 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：:The least known parameters in a Monte Carlo simulation of a linear accelerator treatment head are often the properties of the initial electron beam directed onto the exit vacuum window. Several initial beams with different spatial fluence distributions, angular divergences and energy spectra have been transported thro...

journal_title：Physics in medicine and biology

authors： Björk P,Knöös T,Nilsson P

更新日期：2002-11-21 00:00:00

abstract：:A single experimental apparatus has been designed to allow measurements of stopping cross-sections of materials in liquid and vapour phase, for alpha particles, using an indirect method. The method, in which residual energies for increasing absorber thicknesses are obtained and differentiated, has been used in a numbe...

journal_title：Physics in medicine and biology

authors： Thwaites DI

更新日期：1980-09-01 00:00:00

abstract：:Fixed-pattern noise in electronic portal images (EPIs) is normally eliminated by dividing raw image data by an open-field calibration image (OFCI). However, for successful elimination, there must be exact registration between the two image sets. Any movement within the imaging system, such as that which occurs with ga...

journal_title：Physics in medicine and biology

authors： Kirby MC

更新日期：1996-11-01 00:00:00

abstract：:We propose a novel scintillation detector design for positron emission tomography (PET), which has depth of interaction (DOI) capability and uses a single-ended readout scheme. The DOI detector contains a pair of crystal bars segmented using sub-surface laser engraving (SSLE). The two crystal bars are optically couple...

journal_title：Physics in medicine and biology

authors： Uchida H,Sakai T,Yamauchi H,Hakamata K,Shimizu K,Yamashita T

更新日期：2016-09-21 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：:A phantom study was performed in full-field digital mammography to investigate the opportunity and the magnitude of a possible dose reduction that would leave the image quality above the accepted thresholds associated with some classical phantoms. This preliminary work is intended to lay the groundwork for a future cl...

journal_title：Physics in medicine and biology

authors： Gennaro G,Katz L,Souchay H,Alberelli C,di Maggio C

更新日期：2005-04-21 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：:A 3D anatomical computational model is developed to assess thermal effects due to exposure to the electromagnetic field required to power a new investigational active implantable microvalve for the treatment of glaucoma. Such a device, located in the temporal superior eye quadrant, produces a filtering bleb, which is ...

journal_title：Physics in medicine and biology

authors： Schaumburg F,Guarnieri FA

更新日期：2017-05-07 00:00:00

abstract：:Dose to water (Dw) determination in clinical high-energy photon beams with ionization chambers calibrated in terms of absorbed dose to water has been proposed as an alternative to ionization chamber dosimetry based on air kerma calibrations. Dw in the clinical beam is derived using a kappaQ factor that scales the abso...

journal_title：Physics in medicine and biology

authors： Palmans H,Mondelaers W,Thierens H

更新日期：1999-03-01 00:00:00

abstract：:A complete characterization of spongiosa (bone marrow plus trabecular bone) is required to calculate the absorbed dose to active bone marrow. Due to the complex microanatomy, it is necessary to apply non-conventional imaging methods in nuclear medicine. The aim of this study is validating a phantomless quantification ...

journal_title：Physics in medicine and biology

authors： Salas-Ramirez M,Tran-Gia J,Gbureck U,Kosmala A,Lassmann M

更新日期：2019-10-16 00:00:00

abstract：:In radiotherapy with photon beams, the use of dynamic wedges, which are obtained by the movement of one of the jaws, offers an increasing flexibility relative to the traditional use of metal wedges. But it is a disadvantage for the measurement of absorbed dose distributions, because the absorbed dose at each measureme...

journal_title：Physics in medicine and biology

authors： Storchi P,Woudstra E,Verlinde P,Johansson KA,Samuelsson A

更新日期：1998-06-01 00:00:00

abstract：:In order to effectively utilize the prominent properties of heavy ions in radiotherapy, it is important to evaluate both the position of the field irradiated with incident ions and the absorbed dose distribution in a patient's body. One of the methods for this purpose is the utilization of the positron emitters produc...

journal_title：Physics in medicine and biology

authors： Inaniwa T,Kohno T,Tomitani T,Sato S

更新日期：2008-02-07 00:00:00

abstract：:Radiomic features achieve promising results in cancer diagnosis, treatment response prediction, and survival prediction. Our goal is to compare the handcrafted (explicitly designed) and deep learning (DL)-based radiomic features extracted from pre-treatment diffusion-weighted magnetic resonance images (DWIs) for predi...

journal_title：Physics in medicine and biology

authors： Fu J,Zhong X,Li N,Van Dams R,Lewis J,Sung K,Raldow AC,Jin J,Qi XS

更新日期：2020-04-02 00:00:00

abstract：:The anisotropic mechanical properties (mechanical anisotropy) and view-dependent ultrasonic backscattering (acoustic anisotropy) of striated muscle due to the underlying myofiber arrangement have been well documented, but whether they impact on ultrasound strain imaging (USI) techniques remains unclear. The aim of thi...

journal_title：Physics in medicine and biology

authors： Li H,Lee WN

更新日期：2017-02-21 00:00:00

abstract：:This study introduces a practical four-dimensional (4D) planning scheme of IMAT using 4D computed tomography (4D CT) for planning tumor tracking with dynamic multileaf beam collimation. We assume that patients can breathe regularly, i.e. the same way as during 4D CT with an unchanged period and amplitude, and that the...

journal_title：Physics in medicine and biology

authors： Niu Y,Betzel GT,Yang X,Gui M,Parke WC,Yi B,Yu CX

更新日期：2017-02-21 00:00:00

abstract：:The purpose of this paper for four-dimensional (4D) computed tomography (CT) is threefold. (1) A new spatiotemporal model is presented from the matrix perspective with the row dimension in space and the column dimension in time, namely the robust PCA (principal component analysis)-based 4D CT model. That is, instead o...

journal_title：Physics in medicine and biology

authors： Gao H,Cai JF,Shen Z,Zhao H

更新日期：2011-06-07 00:00:00