High-resolution numerical model of the middle and inner ear for a detailed analysis of radio frequency absorption.

abstract：:The potential of the variable-aperture collimator (VAC) in intensity-modulated radiation therapy (IMRT) has been evaluated by comparing its performance with that of the multi-leaf collimator (MLC). This comparison used a decomposition algorithm to find the series of collimator segments that would treat a given intensi...

journal_title：Physics in medicine and biology

authors： Anderson JW,Symonds-Tayler R,Hartmann G,Echner G,Lang C,Schlegel W,Webb S

更新日期：2006-04-07 00:00:00

abstract：:Stopping power data for protons in tissue-equivalent gas (64.4% CH4 + 32.4% CO2 + 3.2% N2, partial pressures) were derived from experimentally determined ranges and from differential ionisation distributions using the differential energy required per ion pair formed to convert ionisation to energy loss. The proton ene...

journal_title：Physics in medicine and biology

authors： Waibel E,Willems G

更新日期：1987-03-01 00:00:00

abstract：:To replace the conventional pinhole (normal cone-beam) collimator, a novel skew-slit collimator was previously proposed and a Novikov-type algorithm developed to reconstruct images using the skew-slit geometry. The goal of this paper is to develop a reconstruction algorithm that has better noise control than the Novik...

journal_title：Physics in medicine and biology

authors： Tang Q,Zeng GL,Huang Q

更新日期：2006-12-07 00:00:00

abstract：:Light propagation in a turbid medium is considered using the linear transport equation. The existence of a diffusion length is proved for the Henyey-Greenstein scattering kernel for all absorption ratios. Numerical methods are given that allow accurate computation of the diffusion coefficient quite easily. ...

journal_title：Physics in medicine and biology

authors： Sahni DC,Dahl EB,Sjöstrand NG

更新日期：2003-12-07 00:00:00

abstract：:The UMC Utrecht is constructing a 1.5 T MRI scanner integrated with a linear accelerator (Lagendijk et al 2008 Radiother. Oncol. 86 25-9). The goal of this device is to facilitate soft-tissue contrast based image-guided radiotherapy, in order to escalate the dose to the tumour while sparing surrounding normal tissues....

journal_title：Physics in medicine and biology

authors： Meijsing I,Raaymakers BW,Raaijmakers AJ,Kok JG,Hogeweg L,Liu B,Lagendijk JJ

更新日期：2009-05-21 00:00:00

abstract：:An ultrahigh-resolution full-field optical coherence tomography (OCT) system has been developed for cellular-level imaging of biological media. The system is based on a Linnik interference microscope illuminated with a tungsten halogen lamp, associated with a high-resolution CCD camera. En face tomographic images are ...

journal_title：Physics in medicine and biology

authors： Dubois A,Moneron G,Grieve K,Boccara AC

更新日期：2004-04-07 00:00:00

abstract：:Grating interferometry is advantageous over conventional x-ray absorption imaging because it enables the detection of samples constituted by low atomic number elements (low-Z materials). Therefore, it has a potential application in biological science and medical diagnostics. The grating interferometry has some critica...

journal_title：Physics in medicine and biology

authors： Du Y,Lei Y,Liu X,Huang J,Zhao Z,Guo J,Li J,Niu H

更新日期：2016-12-07 00:00:00

abstract：:The measurand relevant for the dosimetry for radiation therapy is the absorbed dose to water, DW. The Physikalisch-Technische Bundesanstalt (PTB) is establishing a secondary standard for DW for high-energy photon and electron radiation based on electron spin resonance (ESR) of the amino acid alanine. For practical app...

journal_title：Physics in medicine and biology

authors： Anton M

更新日期：2008-03-07 00:00:00

abstract：:Cardiac and respiratory motion artefacts in PET imaging have been traditionally resolved by acquiring the data in gated mode. However, gated PET images are usually characterized by high noise content due to their low photon statistics. In this paper, we present a novel 4D model for the PET imaging system, which can in...

journal_title：Physics in medicine and biology

authors： Qiao F,Pan T,Clark JW Jr,Mawlawi OR

更新日期：2006-08-07 00:00:00

abstract：:Brain stereotactic radiosurgery (SRS) treatments require multiple quality assurance (QA) procedures to ensure accurate and precise treatment delivery. As single-isocenter multitarget SRS treatments become more popular, the quantification of off-axis accuracy of the linear accelerator is crucial. In this study, a novel...

journal_title：Physics in medicine and biology

authors： Capaldi DPI,Skinner LB,Dubrowski P,Yu AS

更新日期：2020-06-10 00:00:00

abstract：:Following the publication of ICRU Report 50, the concepts of GTV (gross tumour volume). CTV (clinical target volume) and PTV (planning target volume) are being used in radiotherapy planning with increasing frequency. In 3D planning, the GTV (or CTV) is normally outlined by the clinician in CT or MRI slices. The PTV is...

journal_title：Physics in medicine and biology

authors： Stroom JC,Storchi PR

更新日期：1997-04-01 00:00:00

abstract：:Users of nuclear and atomic data for biomedical purposes often have difficulty in identifying the most up-to-date and appropriate sources of such data. The biomedical Subcommittee of the UK Nuclear Data Committee have prepared a list of recommended data sources available at the beginning of 1978 on radioactive decay s...

journal_title：Physics in medicine and biology

authors： Holt PD

更新日期：1979-01-01 00:00:00

abstract：:Heterogeneity corrections for radiotherapy dose calculations are based on the electron density of the disturbing heterogeneity. However, when CT planning a radiotherapy treatment, where metallic hip implants are present, considerable artefacts are seen in the images. Often, an additional problem arises whereby no info...

journal_title：Physics in medicine and biology

authors： Coolens C,Childs PJ

更新日期：2003-06-07 00:00:00

abstract：:Dual-energy x-ray absorptiometry (DXA) is widely applied for estimating body fat. The percentage of body mass as fat (%fat) is predicted from a DXA-estimated R(ST) value defined as the ratio of soft tissue attenuation at two photon energies (e.g., 40 keV and 70 keV). Theoretically, the R(ST) concept depends on the mas...

journal_title：Physics in medicine and biology

authors： Wang Z,Heymsfield SB,Chen Z,Zhu S,Pierson RN

更新日期：2010-05-07 00:00:00

abstract：:Ion beam therapy offers the possibility of a highly conformal tumor-dose distribution; however, this technique is extremely sensitive to inaccuracies in the treatment procedures. Ambiguities in the conversion of Hounsfield units of the treatment planning x-ray CT to relative stopping power (RSP) can cause uncertaintie...

journal_title：Physics in medicine and biology

authors： Meyer S,Gianoli C,Magallanes L,Kopp B,Tessonnier T,Landry G,Dedes G,Voss B,Parodi K

更新日期：2017-02-07 00:00:00

abstract：:The measurement of beam data for dynamic wedge dosimetry requires the integration of radiation dose at points across the radiation field during the dose delivery. The different measurement techniques required when using a linear diode array to measure beam profiles and when using ionization chambers to measure depth d...

journal_title：Physics in medicine and biology

authors： Bidmead AM,Garton AJ,Childs PJ

更新日期：1995-03-01 00:00:00

abstract：:A three-dimensional spherical inclusion model that approximates a lesion bonded to a tissue matrix is proposed for biomedical elastography. Analytical formulae describing spatial strain and stress distributions generated in infinite media by uniform loading are given under a linear, homogeneous, isotropic elasticity a...

journal_title：Physics in medicine and biology

authors： Bilgen M,Insana MF

更新日期：1998-01-01 00:00:00

abstract：:Heating induced near deep brain stimulation (DBS) lead electrodes during magnetic resonance imaging with a 3 T transceive head coil was measured, modeled, and imaged in three cadaveric porcine heads (mean body weight = 85.47 ± 3.19 kg, mean head weight = 5.78 ± 0.32 kg). The effect of the placement of the extra-crania...

journal_title：Physics in medicine and biology

authors： Shrivastava D,Abosch A,Hughes J,Goerke U,DelaBarre L,Visaria R,Harel N,Vaughan JT

更新日期：2012-09-07 00:00:00

abstract：:In the real-time tumor-tracking radiotherapy system, fluoroscopy is used to determine the real-time position of internal fiducial markers. The pattern recognition score (PRS) ranging from 0 to 100 is computed by a template pattern matching technique in order to determine the marker position on the fluoroscopic image. ...

journal_title：Physics in medicine and biology

authors： Miyamoto N,Ishikawa M,Bengua G,Sutherland K,Suzuki R,Kimura S,Shimizu S,Onimaru R,Shirato H

更新日期：2011-08-07 00:00:00

abstract：:The aim of magnetic resonance electrical impedance tomography (MREIT) is to visualize the electrical properties, conductivity or current density of an object by injection of current. Recently, the prolonged data acquisition time when using the injected current nonlinear encoding (ICNE) method has been advantageous for...

journal_title：Physics in medicine and biology

authors： Nam HS,Kwon OI

更新日期：2010-05-07 00:00:00

abstract：:Large blood vessels can produce steep temperature gradients in heated tissues leading to inadequate tissue temperatures during hyperthermia. This paper utilizes a finite difference scheme to solve the basic equations of heat transfer and fluid flow to model blood vessel cooling. Unlike previous formulations, heat tran...

journal_title：Physics in medicine and biology

authors： Kolios MC,Sherar MD,Hunt JW

更新日期：1995-04-01 00:00:00

abstract：:This paper addresses fundamental issues that underlie the interpretation of images acquired from turbid tissues by optical-coherence tomography (OCT). The attenuation and backscattering properties of freshly excised rat arteries and their dependence on the focusing and collection optics of the OCT system were measured...

journal_title：Physics in medicine and biology

authors： Schmitt JM,Knüttel A,Yadlowsky M,Eckhaus MA

更新日期：1994-10-01 00:00:00

abstract：:K-edge subtraction (KES) imaging is a technique able to map a specific element such as e.g. a contrast agent within the tissues, by exploiting the sharp rise of its absorption coefficient at the K-edge energy. Whereas mainly explored at synchrotron radiation sources, the energy discrimination properties of modern x-ra...

journal_title：Physics in medicine and biology

authors： Brun F,Di Trapani V,Albers J,Sacco P,Dreossi D,Brombal L,Rigon L,Longo R,Mittone A,Dullin C,Bravin A,Delogu P

更新日期：2020-03-06 00:00:00

abstract：:Recently, the Task Group 103 of the International Commission on Radiological Protection (ICRP) has developed new mesh-type reference computational phantoms (MRCPs) for adult male and female. When compared to the current voxel-type reference computational phantoms in ICRP Publication 110, the MRCPs have several advanta...

journal_title：Physics in medicine and biology

authors： Lee H,Yeom YS,Nguyen TT,Choi C,Han H,Shin B,Zhang X,Kim CH,Chung BS,Zankl M

更新日期：2019-02-05 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：: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：:Tumor motion is a particular concern for a complex treatment modality such as helical tomotherapy, where couch position, gantry rotation and MLC leaf opening all change with time. In the present study, we have investigated the impact of tumor motion for helical tomotherapy, which could result in three distinct motion-...

journal_title：Physics in medicine and biology

authors： Kim B,Chen J,Kron T,Battista J

更新日期：2009-10-07 00:00:00

abstract：:The treatment of lung cancer with radiation therapy is hindered by respiratory motion. Real-time adjustments to compensate for this motion are hampered by mechanical system latencies and imaging-rate restrictions. To better understand tumour motion behaviour for adaptive image-guided radiation therapy of lung cancer, ...

journal_title：Physics in medicine and biology

authors： Pepin EW,Wu H,Sandison GA,Langer M,Shirato H

更新日期：2010-06-21 00:00:00

abstract：:Component-based normalization is a method used to compensate for the sensitivity of each of the lines of response acquired in positron emission tomography. This method consists of modelling the sensitivity of each line of response as a product of multiple factors, which can be classified as time-invariant, time-varian...

journal_title：Physics in medicine and biology

authors： Belzunce MA,Reader AJ

更新日期：2016-05-07 00:00:00

abstract：:Clinical diffusion MRI (dMRI) is sensitive to micrometer scale spin displacements, but the image resolution is  ∼mm, so the biophysical interpretation of the signal relies on establishing appropriate subvoxel tissue models. A class of two-compartment exchange models originally proposed by Kärger have been used success...

journal_title：Physics in medicine and biology

authors： Naughton NM,Georgiadis JG

更新日期：2019-08-01 00:00:00