Sensitivity of different dose scoring methods on organ-specific neutron dose calculations in proton therapy.

abstract：:Absorption and emission optical projection tomography (OPT), alternatively referred to as optical computed tomography (optical-CT) and optical-emission computed tomography (optical-ECT), are recently developed three-dimensional imaging techniques with value for developmental biology and ex vivo gene expression studies...

journal_title：Physics in medicine and biology

authors： Fumene Feruglio P,Vinegoni C,Gros J,Sbarbati A,Weissleder R

更新日期：2010-09-21 00:00:00

abstract：:IMRT optimization is an iterative process in which many dose calculations may be necessary. A fast and accurate dose calculation engine is essential for the optimization program to converge to a reliable solution in a reasonable time. Previously we developed a fast dose calculation method for IMRT optimization based o...

journal_title：Physics in medicine and biology

authors： Wu Q

更新日期：2004-10-07 00:00:00

abstract：:We have shown that irradiation changes the dielectric properties of human skin at radiofrequencies. Both the dielectric constant and the conductivity of the irradiated skin decrease, especially at low frequencies. The experimental data were analysed using two bioelectric models. Relevant dielectric parameters were det...

journal_title：Physics in medicine and biology

authors： Tamura T,Tenhunen M,Lahtinen T,Repo T,Schwan HP

更新日期：1994-06-01 00:00:00

abstract：:The sensitivity and detection limit for measurements of the concentration of cadmium in the kidney cortex of man in vivo have been investigated using the technique of X-ray fluorescence. An 11 GB1 241Am source was used to generate the characteristic K alpha X-rays of cadmium. The variation in the sensitivity for the d...

journal_title：Physics in medicine and biology

authors： Ahlgren L,Mattsson S

更新日期：1981-01-01 00:00:00

abstract：:The aim of this study is to calculate realistic dose distributions that include the continuous deformation of organs and continuous motion of machine using 4D Monte Carlo methods for both volumetric modulated arc therapy and helical tomotherapy treatments. As part of a previous study, we presented a method to perform ...

journal_title：Physics in medicine and biology

authors： Belec J,Clark BG

更新日期：2013-05-07 00:00:00

abstract：:We give an overview of the role of Physics in Medicine and Biology in the development of tomographic reconstruction algorithms. We focus on imaging modalities involving ionizing radiation, CT, PET and SPECT, and cover a wide spectrum of reconstruction problems, starting with classical 2D tomography in the 1970s up to ...

journal_title：Physics in medicine and biology

authors： Defrise M,Gullberg GT

更新日期：2006-07-07 00:00:00

abstract：:Assessment of image quality for digital x-ray mammography systems used in European screening programs relies mainly on contrast-detail CDMAM phantom scoring and requires the acquisition and analysis of many images in order to reduce variability in threshold detectability. Part II of this study proposes an alternative ...

journal_title：Physics in medicine and biology

authors： Monnin P,Marshall NW,Bosmans H,Bochud FO,Verdun FR

更新日期：2011-07-21 00:00:00

abstract：:A Geiger-mode avalanche photodiode (Si-PM) is a promising photodetector for PET, especially for use in a magnetic resonance imaging (MRI) system, because it has high gain and is less sensitive to a static magnetic field. We developed a Si-PM-based depth-of-interaction (DOI) PET system for small animals. Hamamatsu 4 × ...

journal_title：Physics in medicine and biology

authors： Yamamoto S,Imaizumi M,Watabe T,Watabe H,Kanai Y,Shimosegawa E,Hatazawa J

更新日期：2010-10-07 00:00:00

abstract：:We evaluated the basic properties of a commercially available BANGkit gel dosimeter, which is a normoxic type of BANG gel. This gel-kit has the same composition as the BANG 3 gel, but is fully oxygenated. To exclude oxygen, oxygen scavenging ascorbic acid and copper sulfate as a catalyst are used. The properties that ...

journal_title：Physics in medicine and biology

authors： Murakami Y,Nakashima T,Watanabe Y,Akimitsu T,Matsuura K,Kenjo M,Kaneyasu Y,Wadasaki K,Hirokawa Y,Ito K

更新日期：2007-04-21 00:00:00

abstract：:Recently, there has been a resurgence of interest in arc-based IMRT, through the use of 'conventional' multileaf collimator (MLC) systems that can treat large tumor volumes in a single, or very few pass(es) of the gantry. Here we present a novel 'burst mode' modulated arc delivery approach, wherein 2000 monitor units ...

journal_title：Physics in medicine and biology

authors： Salter BJ,Sarkar V,Wang B,Shukla H,Szegedi M,Rassiah-Szegedi P

更新日期：2011-04-07 00:00:00

abstract：:Rotational coronary angiography provides a multitude of x-ray projections of the contrast agent enhanced coronary arteries along a given trajectory with parallel ECG recording. These data can be used to derive motion information of the coronary arteries including vessel displacement and pulsation. In this paper, a ful...

journal_title：Physics in medicine and biology

authors： Jandt U,Schäfer D,Grass M,Rasche V

更新日期：2009-01-07 00:00:00

abstract：:Accumulating evidence shows that hyperthermia improves head-and-neck cancer treatment. Over the last decade, we introduced a radiofrequency applicator, named HYPERcollar, which enables local heating also of deep locations in this region. Based on clinical experience, we redesigned the HYPERcollar for improved comfort,...

journal_title：Physics in medicine and biology

authors： Togni P,Rijnen Z,Numan WC,Verhaart RF,Bakker JF,van Rhoon GC,Paulides MM

更新日期：2013-09-07 00:00:00

abstract：:Nuclear medicine and radiation therapy, although well established, are still rapidly evolving, by exploiting animal models, aiming to define precise dosimetry in molecular imaging protocols. The purpose of the present study was to create a dataset based on the MOBY phantom for the calculation of organ-to-organ S-value...

journal_title：Physics in medicine and biology

authors： Kostou T,Papadimitroulas P,Loudos G,Kagadis GC

更新日期：2016-03-21 00:00:00

abstract：:This study presents a theoretical approach to the dosimetry for small and non-equilibrium radiation fields. We applied the newly developed VMCBC algorithm to the dosimetry for megavoltage photon beams using Monte Carlo techniques. The approach assumes that a Monte Carlo simulated beam can be calibrated per incident pa...

journal_title：Physics in medicine and biology

authors： Ding GX,Duggan DM,Coffey CW

更新日期：2008-07-07 00:00:00

abstract：:Numerical computations are used to evaluate electric field dosimetry for high-resolution anatomically based inhomogeneous models of a human male child, and male and female rats and mice, under exposure to 60 Hz uniform magnetic field sources of three perpendicular orientations. The goal is to compare the child data to...

journal_title：Physics in medicine and biology

authors： Dawson TW,Caputa K,Stuchly MA

更新日期：2002-07-21 00:00:00

abstract：:Flow visualization, particle image velocimetry and numerical computation have been complementarily performed to study the fluid flow inside a stented lateral aneurysm. The curved afferent vessel had an inner diameter of 5 mm. The diameters of the aneurysmal orifice, neck and fundus were 7 mm, 5 mm and 7.5 mm, respecti...

journal_title：Physics in medicine and biology

authors： Liou TM,Li YC,Wang TC

更新日期：2008-07-21 00:00:00

abstract：:We present a method to include robustness in a multi-criteria optimization (MCO) framework for intensity-modulated proton therapy (IMPT). The approach allows one to simultaneously explore the trade-off between different objectives as well as the trade-off between robustness and nominal plan quality. In MCO, a database...

journal_title：Physics in medicine and biology

authors： Chen W,Unkelbach J,Trofimov A,Madden T,Kooy H,Bortfeld T,Craft D

更新日期：2012-02-07 00:00:00

abstract：:Many models exist for predicting toxicities based on dose-volume histograms (DVHs) or dose-surface histograms (DSHs). This approach has several drawbacks as firstly the reduction of the dose distribution to a histogram results in the loss of spatial information and secondly the bins of the histograms are highly correl...

journal_title：Physics in medicine and biology

authors： Buettner F,Gulliford SL,Webb S,Partridge M

更新日期：2011-04-07 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：:Breast-conserving surgery is a standard option for the treatment of patients with early-stage breast cancer. This form of surgery may result in incomplete excision of the tumor. Iodine-125 labeled titanium seeds are currently used in clinical practice to reduce the number of incomplete excisions. It seems likely that ...

journal_title：Physics in medicine and biology

authors： Arsenali B,de Jong HW,Viergever MA,Dickerscheid DB,Beijst C,Gilhuijs KG

更新日期：2015-10-07 00:00:00

abstract：:The purpose of this study is to develop a new global mammographic image feature analysis based computer-aided detection (CAD) scheme and evaluate its performance in detecting positive screening mammography examinations. A dataset that includes images acquired from 1896 full-field digital mammography (FFDM) screening e...

journal_title：Physics in medicine and biology

authors： Tan M,Qian W,Pu J,Liu H,Zheng B

更新日期：2015-06-07 00:00:00

abstract：:Breast MRI is frequently performed prior to breast conserving surgery in order to assess the location and extent of the lesion. Ideally, the surgeon should also be able to use the image information during surgery to guide the excision and this requires that the MR image is co-registered to conform to the patient's pos...

journal_title：Physics in medicine and biology

authors： Ebrahimi M,Siegler P,Modhafar A,Holloway CM,Plewes DB,Martel AL

更新日期：2014-04-07 00:00:00

abstract：:In recent years, particle therapy has become a widely accepted form of cancer treatment and technological advances in beam delivery technology (i.e. pencil beam scanning (PBS)) have enabled the application of highly conformal dose distributions to static targets. Current research focuses on the possibilities for the t...

journal_title：Physics in medicine and biology

authors： Bernatowicz K,Lomax AJ,Knopf A

更新日期：2013-11-21 00:00:00

abstract：:Motion mitigation strategies are crucial for scanned particle therapy of mobile tumours in order to prevent geometrical target miss and interplay effects. We developed a patient-specific respiratory motion model based on simultaneously acquired time-resolved volumetric MRI and 2D abdominal ultrasound images. We presen...

journal_title：Physics in medicine and biology

authors： Giger AT,Krieger M,Jud C,Duetschler A,Salomir R,Bieri O,Bauman G,Nguyen D,Weber DC,Lomax AJ,Zhang Y,Cattin PC

更新日期：2020-07-28 00:00:00

abstract：:We present a new image reconstruction algorithm for helical cone-beam computed tomography (CT). This algorithm is designed for data collected at or near maximum pitch, and provides a theoretically exact and stable reconstruction while beneficially using all measured data. The main operations involved are a differentia...

journal_title：Physics in medicine and biology

authors： Schöndube H,Stierstorfer K,Noo F

更新日期：2009-08-07 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：:We investigated the physical characteristics of two complementary metal oxide semiconductor (CMOS) mammography detectors. The detectors featured 14-bit image acquisition, 50 microm detector element (del) size and an active area of 5 cm x 5 cm. One detector was a passive-pixel sensor (PPS) with signal amplification per...

journal_title：Physics in medicine and biology

authors： Elbakri IA,McIntosh BJ,Rickey DW

更新日期：2009-03-21 00:00:00

abstract：:Ultrasound-based elastography including strain elastography, acoustic radiation force impulse (ARFI) imaging, point shear wave elastography and supersonic shear imaging (SSI) have been used to differentiate breast tumors among other clinical applications. The objective of this study is to extend a previously published...

journal_title：Physics in medicine and biology

authors： Wang Y,Peng B,Jiang J

更新日期：2017-03-07 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：:We show that it is possible to translate an intensity modulated radiation therapy (IMRT) treatment plan and deliver it as a single arc. This technique is referred to in this paper as aperture modulation arc therapy (AMAT). During this arc, the MLC leaves do not conform to the projection of the target PTV and the machi...

journal_title：Physics in medicine and biology

authors： Crooks SM,Wu X,Takita C,Watzich M,Xing L

更新日期：2003-05-21 00:00:00