Dosimetry of 106Ru eye applicators with a p-type silicon detector.

abstract：:Dynamic positron emission tomography (PET) imaging can provide information about metabolic changes over time, used for kinetic analysis and auxiliary diagnosis. Existing deep learning-based reconstruction methods have too many trainable parameters and poor generalization, and require mass data to train the neural netw...

journal_title：Physics in medicine and biology

authors： Wang B,Liu H

更新日期：2020-10-13 00:00:00

abstract：:Dynamic modulation can be affected by inaccuracies when the required acceleration is larger than the highest allowed by the mechanical characteristics of the whole apparatus. In this study, inertia effects have been investigated with regard to the single absorber 1D modulation, analysing primarily how the acceleration...

journal_title：Physics in medicine and biology

authors： Corletto D,Broggi S,Fiorino C,Mangili P,Calandrino R,Lev A,Gennari D,Rudello F

更新日期：1999-11-01 00:00:00

abstract：:In this paper we describe measurements of the contrast transfer function, modulation transfer function and point-spread function of an optical coherence tomography (OCT) imaging system through scattering layers having a dimension-less scattering depth over the range 0.2-6.9. The results were found to be insensitive to...

journal_title：Physics in medicine and biology

authors： Woolliams PD,Tomlins PH

更新日期：2011-05-07 00:00:00

abstract：:In recent codes of practice for reference dosimetry in clinical proton beams using ionization chambers, it is recommended to perform the measurement in a water phantom. However, in situations where the positioning accuracy is very critical, it could be more convenient to perform the measurement in a plastic phantom. I...

journal_title：Physics in medicine and biology

authors： Palmans H,Symons JE,Denis JM,de Kock EA,Jones DT,Vynckier S

更新日期：2002-09-07 00:00:00

abstract：:Radiobiological models for estimating normal tissue complication probability (NTCP) are increasingly used in order to quantify or optimize the clinical outcome of radiation therapy. A good NTCP model should fulfill at least the following two requirements: (a) it should predict the sigmoid shape of the corresponding do...

journal_title：Physics in medicine and biology

authors： Adamus-Górka M,Mavroidis P,Brahme A,Lind BK

更新日期：2008-11-21 00:00:00

abstract：:Medulloblastoma treatment involves irradiation of the entire central nervous system, i.e. craniospinal irradiation (CSI). This is associated with the significant exposure of large volumes of healthy tissue and there is growing concern regarding treatment-associated side effects. The current study compares out-of-field...

journal_title：Physics in medicine and biology

authors： De Saint-Hubert M,Verellen D,Poels K,Crijns W,Magliona F,Depuydt T,Vanhavere F,Struelens L

更新日期：2017-07-07 00:00:00

abstract：:The purpose of this study is to evaluate a new method to improve performance of computer-aided detection (CAD) schemes of screening mammograms with two approaches. In the first approach, we developed a new case based CAD scheme using a set of optimally selected global mammographic density, texture, spiculation, and st...

journal_title：Physics in medicine and biology

authors： Tan M,Aghaei F,Wang Y,Zheng B

更新日期：2017-01-21 00:00:00

abstract：:Non-pure positron emitters, with their long half-lives, allow for the tracing of slow biochemical processes which cannot be adequately examined by the commonly used short-lived positron emitters. Most of these isotopes emit high-energy cascade gamma rays in addition to positron decay that can be detected and create a ...

journal_title：Physics in medicine and biology

authors： Lin HH,Chuang KS,Chen SY,Jan ML

更新日期：2016-03-07 00:00:00

abstract：:In this study, the quantitative accuracy of different attenuation correction strategies presently available for the High Resolution Research Tomograph (HRRT) was investigated. These attenuation correction methods differ in reconstruction and processing (segmentation) algorithms used for generating a micro-image from m...

journal_title：Physics in medicine and biology

authors： van Velden FH,Kloet RW,van Berckel BN,Molthoff CF,de Jong HW,Lammertsma AA,Boellaard R

更新日期：2008-01-07 00:00:00

abstract：:Amorphous silicon (aSi:H) flat panel detectors are prevalent in radiotherapy for megavoltage imaging tasks. Any clinical and dosimetrical application requires a well-defined dose response of the system to achieve meaningful results. Due to radiation damages, panels deteriorate and the linearity of pixel response to do...

journal_title：Physics in medicine and biology

authors： Huber S,Mooslechner M,Mitterlechner B,Weichenberger H,Serpa M,Sedlmayer F,Deutschmann H

更新日期：2013-09-21 00:00:00

abstract：:In this response we underscore that the instrumentation described in the original publication (Liu et al 2012 Phys. Med. Biol. 57 843-65) was based on pulse-sampling technique, while the comment by Zhang et al is based on the assumption that a time-correlated single photon counting (TCSPC) instrumentation was used. Th...

journal_title：Physics in medicine and biology

authors： Ma D,Liu J,Qi J,Marcu L

更新日期：2017-02-21 00:00:00

abstract：:Measurement of the dielectric properties of ocular tissues up to 110 GHz was performed by the coaxial probe method. A coaxial sensor was fabricated to allow the measurement of small amounts of biological tissues. Four-standard calibration was applied in the dielectric property measurement to obtain more accurate data ...

journal_title：Physics in medicine and biology

authors： Sasaki K,Isimura Y,Fujii K,Wake K,Watanabe S,Kojima M,Suga R,Hashimoto O

更新日期：2015-08-21 00:00:00

abstract：:The 50-year tenure of Physics in Medicine and Biology has coincided with some of the most important developments in radiological science, including the introduction of artificial radioactivity, computers and 3D imaging into medicine. These events have profoundly influenced the development of brachytherapy. Although it...

journal_title：Physics in medicine and biology

authors： Williamson JF

更新日期：2006-07-07 00:00:00

abstract：:Magnetic Particle Imaging (MPI) is a novel technology, which opens new possibilities for promising biomedical applications. MPI uses magnetic fields to generate a specific response from magnetic nanoparticles (MNPs), to determine their spatial location non-invasively and without using ionizing radiation. One open chal...

journal_title：Physics in medicine and biology

authors： Paysen H,Kosch O,Wells J,Loewa N,Wiekhorst F

更新日期：2020-10-21 00:00:00

abstract：:Mitral and aortic valve replacement is a procedure which is common in cardiac surgery. Some of these replacement valves are mechanical and contain moving metal parts. Should the patient in whom such a valve has been implanted be involved in magnetic resonance imaging, there is a possible dangerous interaction between ...

journal_title：Physics in medicine and biology

authors： Robertson NM,Diaz-Gomez M,Condon B

更新日期：2000-12-01 00:00:00

abstract：:We report on a radiographic measurement of an ex vivo human knee using a grating-based phase-contrast imaging setup and a medical x-ray tube at a tube voltage of 70 kV. The measurement has been carried out using a Talbot-Lau setup that is suitable to achieve a high visibility in the energy regime of medical imaging. I...

journal_title：Physics in medicine and biology

authors： Horn F,Gelse K,Jabari S,Hauke C,Kaeppler S,Ludwig V,Meyer P,Michel T,Mohr J,Pelzer G,Rieger J,Riess C,Seifert M,Anton G

更新日期：2017-08-01 00:00:00

abstract：:The original concept of the echo mechanism in diagnostic medical ultrasound--of step impedance discontinuities--is investigated in terms of the numerical implications of more refined models. The effect of a discontinuity in the attenuation coefficients is found to have as much significance as the impedance discontinui...

journal_title：Physics in medicine and biology

authors： Chivers RC,Santosa F

更新日期：1986-08-01 00:00:00

abstract：:Accurate scatter correction is required to produce high-quality reconstructions of x-ray cone-beam computed tomography (CBCT) scans. This paper describes new scatter kernel superposition (SKS) algorithms for deconvolving scatter from projection data. The algorithms are designed to improve upon the conventional approac...

journal_title：Physics in medicine and biology

authors： Sun M,Star-Lack JM

更新日期：2010-11-21 00:00:00

abstract：:Shear wave elastography (SWE) is a potential tool to non-invasively assess cardiac muscle stiffness. This study focused on the effect of the orthotropic material properties and mechanical loading on the performance of cardiac SWE, as it is known that these factors contribute to complex 3D anisotropic shear wave propag...

journal_title：Physics in medicine and biology

authors： Caenen A,Pernot M,Peirlinck M,Mertens L,Swillens A,Segers P

更新日期：2018-03-23 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：: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：:In this work, a methodology for using a smartphone camera, in conjunction with a light-tight box operating in reflective transmission mode, is investigated as a proof of concept for use as a film dosimetry system. An imaging system was designed to allow the camera of a smartphone to be used as a pseudo densitometer. T...

journal_title：Physics in medicine and biology

authors： Aland T,Jhala E,Kairn T,Trapp J

更新日期：2017-10-03 00:00:00

abstract：:A method is presented to predict beam profiles and outputs for wedged asymmetric fields defined by independent collimator jaws allowing fast generation of beam profiles whilst requiring very little additional data to that already used by most treatment planning systems in generating symmetric field isodoses. Symmetric...

journal_title：Physics in medicine and biology

authors： Millin AE,Smith CW

更新日期：1994-01-01 00:00:00

abstract：:We investigate the effect of multiple scattering on the optical coherence tomography (OCT) signal and the Doppler OCT signal of flowing blood. Doppler OCT measurements at 1300 nm are performed on flowing diluted porcine blood with hematocrit ranging between 0% and 15%. Measured blood hematocrit and mean red blood cell...

journal_title：Physics in medicine and biology

authors： Kalkman J,Bykov AV,Streekstra GJ,van Leeuwen TG

更新日期：2012-04-07 00:00:00

abstract：:Cylindrical ionization chambers with varying radii have been used to determine the displacement effect at distances between 10 mm and 40 mm from 60Co and 192Ir brachytherapy sources. Agreement with published values of the displacement factor for external 60Co beams is obtained. The shift between the centre of the ioni...

journal_title：Physics in medicine and biology

authors： Tölli H,Johansson KA

更新日期：1993-10-01 00:00:00

abstract：:In positron emission tomography (PET), there is an increasing interest in studying not only the regional mean tracer concentration, but its variation arising from local differences in physiology, the tissue heterogeneity. However, in reconstructed images this physiological variation is shadowed by a large reconstructi...

journal_title：Physics in medicine and biology

authors： Forma J,Niemi JA,Ruotsalainen U

更新日期：2013-07-21 00:00:00

abstract：:Modelling of inhaled particle deposition in the lungs potentially offers data relevant to assessing hazards from toxic inhaled particles, to studying mucus clearance or lung permeability by aerosol techniques, and to achieving better utilisation of drugs administered as aerosols. Analysis of published modelling studie...

journal_title：Physics in medicine and biology

authors： Agnew JE,Pavia D,Clarke SW

更新日期：1984-07-01 00:00:00

abstract：:The practical use of a discrete vessel thermal model for hyperthermia treatment planning requires a number of choices with respect to the unknown part of the patient's vasculature. This work presents a study of the thermal effects of blood flow in a simple tissue geometry with a detailed artificial vessel network. The...

journal_title：Physics in medicine and biology

authors： Van Leeuwen GM,Kotte AN,Raaymakers BW,Lagendijk JJ

更新日期：2000-04-01 00:00:00

abstract：:Monitoring the spatio-temporal characteristics of microcirculation is crucial for studying the functional activities of biotissue and the mechanism of disease. However, conventional methods used to measure blood flow suffer from limited spatial resolution or the injection of exogenous substances or the need of scannin...

journal_title：Physics in medicine and biology

authors： Cheng H,Luo Q,Liu Q,Lu Q,Gong H,Zeng S

更新日期：2004-04-07 00:00:00

abstract：:To generate large thermal lesions in ultrasound thermal therapy, cooling intermissions are usually introduced during the treatment to prevent near-field heating, which leads to a long treatment time. A possible strategy to shorten the total treatment time is to eliminate the cooling intermissions. In this study, the t...

journal_title：Physics in medicine and biology

authors： Liu HL,Chen YY,Yen JY,Lin WL

更新日期：2003-05-07 00:00:00