A new method of body habitus correction for total body potassium measurements.

abstract：:Energy and spatial projection distributions were simulated for gamma camera imaging of multiple order Compton scattered photons. SPECT imaging of a line source of radioactivity located in a water filled cylindrical phantom was modelled using Monte Carlo techniques. Photon trajectories were followed from emission to de...

journal_title：Physics in medicine and biology

authors： Floyd CE,Jaszczak RJ,Harris CC,Coleman RE

更新日期：1984-10-01 00:00:00

abstract：:Ring artifacts in cone beam computed tomography (CBCT) images are caused by pixel gain variations using flat-panel detectors, and may lead to structured non-uniformities and deterioration of image quality. The purpose of this study is to propose a method of general ring artifact removal in CBCT images. This method is ...

journal_title：Physics in medicine and biology

authors： Liang X,Zhang Z,Niu T,Yu S,Wu S,Li Z,Zhang H,Xie Y

更新日期：2017-07-07 00:00:00

abstract：:Histotripsy is a therapeutic ultrasound modality under development to liquefy tissue mechanically via bubble clouds. Image guidance of histotripsy requires both quantification of the bubble cloud activity and accurate delineation of the treatment zone. In this study, magnetic resonance (MR) and diagnostic ultrasound i...

journal_title：Physics in medicine and biology

authors： Anthony GJ,Bollen V,Hendley S,Antic T,Sammet S,Bader KB

更新日期：2019-05-02 00:00:00

abstract：:Although radionuclide therapy has been around for a long time, this modality of cancer treatment has been limited mainly to the use of [32P]-phosphate and [131I]-sodium iodide. The last few years, however, have seen an increased interest in this area due to new developments of radionuclides and carrier molecules that ...

journal_title：Physics in medicine and biology

authors： Zweit J

更新日期：1996-10-01 00:00:00

abstract：:Planning of radiotherapy is often difficult due to restrictions on morphological images. New imaging techniques enable the integration of biological information into treatment planning and help to improve the detection of vital and aggressive tumour areas. This might improve clinical outcome. However, nowadays morphol...

journal_title：Physics in medicine and biology

authors： Neff T,Kiessling F,Brix G,Baudendistel K,Zechmann C,Giesel FL,Bendl R

更新日期：2005-09-07 00:00:00

abstract：:Dose calculations were performed for a tissue phantom irradiated by uniform circular beams of negative pions with an assumed gaussian momentum distribution. The mean momentum of the pions was varied from 104.4 to 171.5 MeV/c (mean range 5-20 cm in unit-density tissue) and the momentum spread from 0 to 5% of the mean. ...

journal_title：Physics in medicine and biology

authors： Hamm RN,Wright HA,Turner JE

更新日期：1979-05-01 00:00:00

abstract：:Temperature distributions resulting from hyperthermia treatments on isolated perfused bovine tongues were compared with simulations by a treatment planning system. The aim was to test whether the discrete vessel model used for the treatment planning is able to predict correct generic temperature distributions. Tongues...

journal_title：Physics in medicine and biology

authors： Raaymakers BW,Crezee J,Lagendijk JJ

更新日期：1998-05-01 00:00:00

abstract：:To investigate the detection performance of our automated detection scheme for clustered microcalcifications on mammograms, we applied our computer-aided diagnosis (CAD) system to the database of the Mammographic Image Analysis Society (MIAS) in the UK. Forty-three mammograms from this database were used in this study...

journal_title：Physics in medicine and biology

authors： Ibrahim N,Fujita H,Hara T,Endo T

更新日期：1997-12-01 00:00:00

abstract：:A modified sector-integration method is presented that can predict the output factors of irregular shaped electron fields even in the case of extended source to surface distance (SSD). The model takes as input measured output factors for circular inserts of various radii. These circular fields were measured at SSDs of...

journal_title：Physics in medicine and biology

authors： Choi DR,Wolters J,Mason D,Baillie A

更新日期：2000-11-01 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：:The current UK code of practice for high-energy photon therapy dosimetry (Lillicrap et al 1990 Phys. Med. Biol. 35 1355-60) gives instructions for measuring absorbed dose to water under reference conditions for megavoltage photons. The reference conditions and the index used to specify beam quality require that a mach...

journal_title：Physics in medicine and biology

authors： Thomas SJ,Aspradakis MM,Byrne JP,Chalmers G,Duane S,Rogers J,Thomas RA,Tudor GS,Twyman N,IPEM Working Party.

更新日期：2014-03-21 00:00:00

abstract：:Ultrasoft x-rays of 0.3-5 keV have provided a unique tool for the investigation of intracellular mechanisms of radiation action in biological organisms, including mammalian cells. However, their use presents unique practical problems in dosimetry and experimental design. Detailed interpretation of the biological resul...

journal_title：Physics in medicine and biology

authors： Hoshi M,Goodhead DT,Brenner DJ,Bance DA,Chmielewski JJ,Paciotti MA,Bradbury JN

更新日期：1985-10-01 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：:Diffraction-enhanced imaging (DEI) is an analyser-based x-ray imaging method that produces separate images depicting the projected x-ray absorption and refractive properties of an object. Because the imaging model of DEI does not account for ultra-small-angle x-ray scattering (USAXS), the images produced in DEI can co...

journal_title：Physics in medicine and biology

authors： Chou CY,Anastasio MA,Brankov JG,Wernick MN,Brey EM,Connor DM,Zhong Z

更新日期：2007-04-07 00:00:00

abstract：:A Monte Carlo computational model of a fluoroscopic imaging chain was used for deriving optimal technique factors for paediatric fluoroscopy. The optimal technique was defined as the one that minimizes the absorbed dose (or dose rate) in the patient with a constraint of constant image quality. Image quality was assess...

journal_title：Physics in medicine and biology

authors： Tapiovaara MJ,Sandborg M,Dance DR

更新日期：1999-02-01 00:00:00

abstract：:In this work we present the first delivery of intensity modulated arc therapy on the Elekta Unity 1.5 T MR-linac. The machine's current IMRT based control system was modified suitably to enable dynamic delivery of radiation, for the purpose of exploring MRI-guided radiation therapy adaptation modes in a research setti...

journal_title：Physics in medicine and biology

authors： Kontaxis C,Woodhead PL,Bol GH,Lagendijk JJW,Raaymakers BW

更新日期：2020-12-23 00:00:00

abstract：:In this letter the authors highlight the presence of an error appearing in the discussion of the note 'The use of the Henyey-Greenstein phase function in Monte Carlo simulations in biomedical optics' previously published by them (Binzoni et al 2006 Phys. Med. Biol. 51 N313). In the light of this error, the discussion ...

journal_title：Physics in medicine and biology

authors： Binzoni T,Leung TS,Gandjbakhche AH,Rüfenacht D,Delpy DT

更新日期：2006-11-21 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：: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：:Usually, Monte Carlo models are validated against experimental data. However, models of multiple Coulomb scattering (MCS) in the Gaussian approximation are exceptional in that we have theories which are probably more accurate than the experiments which have, so far, been done to test them. In problems directly sensiti...

journal_title：Physics in medicine and biology

authors： Makarova A,Gottschalk B,Sauerwein W

更新日期：2017-07-06 00:00:00

abstract：:Quantifying the retention or washout of (99m)Tc-Sestamibi (MIBI) in breast tumours in vivo may provide a basis for predicting the chemotherapy response. The aim of this study is to investigate the variations and limitations of the different methods used to quantify these parameters. A phantom was developed that allowe...

journal_title：Physics in medicine and biology

authors： Marshall C,Griffiths PA

更新日期：2005-05-07 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：:The dose-response of LiF:Mg,Ti (TLD-100) exposed to 15 and 35 kVp (8.0 +/- 0.1 and 8.1 +/- 0.1 keV effective energy respectively) x-rays and 60Co gamma-rays has been measured in the dose interval from (1.2-5.4) x 10(3) Gy for x-rays, and from 0.14 to 850 Gy for gamma-rays. In both cases the total TL signal and glow cu...

journal_title：Physics in medicine and biology

authors： Gamboa-deBuen I,Buenfil AE,Ruiz CG,Rodríguez-Villafuerte M,Flores A,Brandan ME

更新日期：1998-08-01 00:00:00

abstract：:The purpose of this work was to use Monte Carlo simulations to verify the accuracy of the dose distributions from a commercial treatment planning optimization system (Corvus, Nomos Corp., Sewickley, PA) for intensity-modulated radiotherapy (IMRT). A Monte Carlo treatment planning system has been implemented clinically...

journal_title：Physics in medicine and biology

authors： Ma CM,Pawlicki T,Jiang SB,Li JS,Deng J,Mok E,Kapur A,Xing L,Ma L,Boyer AL

更新日期：2000-09-01 00:00:00

abstract：:Due to high levels of noise in pixel-wise time-activity curves, the indirect method that generates kinetic parametric images from dynamic positron emission tomography (PET) images often results in poor parametric image quality. We have demonstrated that the quality of parametric images can be improved by denoising dyn...

journal_title：Physics in medicine and biology

authors： Huang HM

更新日期：2020-11-17 00:00:00

abstract：:Accurate real-time prediction of respiratory motion is desirable for effective motion management in radiotherapy for lung tumor targets. Recently, nonparametric methods have been developed and their efficacy in predicting one-dimensional respiratory-type motion has been demonstrated. To exploit the correlation among v...

journal_title：Physics in medicine and biology

authors： Ruan D,Keall P

更新日期：2010-06-07 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：:To achieve accurate and fast deformable image registration (DIR) for pulmonary CT, we proposed a Multi-scale DIR framework with unsupervised Joint training of Convolutional Neural Network (MJ-CNN). MJ-CNN contains three models at multi-scale levels for a coarse-to-fine DIR to avoid being trapped in a local minimum. It...

journal_title：Physics in medicine and biology

authors： Jiang Z,Yin FF,Ge Y,Ren L

更新日期：2020-01-13 00:00:00

abstract：:Maximum likelihood estimation (MLE) is presented as a statistical tool to evaluate the contribution of measurement error to any measurement series where the same quantity is measured using different independent methods. The technique was tested against artificial data sets; generated for values of underlying variation...

journal_title：Physics in medicine and biology

authors： Sage JP,Mayles WP,Mayles HM,Syndikus I

更新日期：2014-10-21 00:00:00

abstract：:Tumour blood flow is one of the important factors limiting the efficacy of radiation therapy (hypoxic radioresistance), chemotherapy (drug delivery) and thermal therapy (heat dissipation) in treating cancer. The modification of tumour blood flow has been an area of intense investigation. In the current study, the arte...

journal_title：Physics in medicine and biology

authors： Purdie TG,Lee TY

更新日期：2003-04-07 00:00:00