Three-dimensional optical tomography of the premature infant brain.

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：:We consider several inverse problems motivated by elastography. Given the (possibly transient) displacement field measured everywhere in an isotropic, compressible, linear elastic solid, and given density rho, determine the Lamé parameters lambda and mu. We consider several special cases of this problem: (a) for mu kn...

journal_title：Physics in medicine and biology

authors： Barbone PE,Oberai AA

更新日期：2007-03-21 00:00:00

abstract：:For quantitative measurements of small animals such as mice or rats, a compact and high sensitivity continuous blood sampling detector is required because their blood sampling volume is limited. For this purpose we have developed and tested a new positron detector. The positron detector uses a pair of dual-layer thin ...

journal_title：Physics in medicine and biology

authors： Yamamoto S,Imaizumi M,Shimosegawa E,Kanai Y,Sakamoto Y,Minato K,Shimizu K,Senda M,Hatazawa J

更新日期：2010-07-07 00:00:00

abstract：:Segmented attenuation correction is now a widely accepted technique to reduce noise propagation from transmission scanning in positron emission tomography (PET). In this paper, we present a new method for segmenting transmission images in whole-body scanning. This reduces the noise in the correction maps while still c...

journal_title：Physics in medicine and biology

authors： Zaidi H,Diaz-Gomez M,Boudraa A,Slosman DO

更新日期：2002-04-07 00:00:00

abstract：:In dual energy x-ray absorptiometry (DXA) the photon attenuation is assumed to be similar in soft tissue overlying, adjacent to and inside the measured bone. In the calcaneal dual energy x-ray laser (DXL) technique, this assumption is not needed as attenuation by soft tissues at the local bone site is determined by co...

journal_title：Physics in medicine and biology

authors： Hakulinen MA,Saarakkala S,Töyräs J,Kröger H,Jurvelin JS

更新日期：2003-06-21 00:00:00

abstract：:A parametric model for the x-ray linear attenuation coefficient is used to describe the compositional dependence of Hounsfield numbers measured by medical CT scanners. Measurements with materials of known density and composition, that span and evenly sample the compositional range of tissues, are written as linear sim...

journal_title：Physics in medicine and biology

authors： Midgley SM

更新日期：2014-12-07 00:00:00

abstract：:Monte Carlo-based simulation of positron emission tomography (PET) data plays a key role in the design and optimization of data correction and processing methods. Our first aim was to adapt and configure the PET-SORTEO Monte Carlo simulation program for the geometry of the widely distributed Inveon PET preclinical sca...

journal_title：Physics in medicine and biology

authors： Boisson F,Wimberley CJ,Lehnert W,Zahra D,Pham T,Perkins G,Hamze H,Gregoire MC,Reilhac A

更新日期：2013-10-07 00:00:00

abstract：:A quantitative comparison of two full three-dimensional (3D) gel dosimetry techniques was assessed in a clinical setting: radiochromic gel dosimetry with an in-house developed optical laser CT scanner and polymer gel dosimetry with magnetic resonance imaging (MRI). To benchmark both gel dosimeters, they were exposed t...

journal_title：Physics in medicine and biology

authors： Vandecasteele J,De Deene Y

更新日期：2013-09-21 00:00:00

abstract：:In digital breast tomosynthesis (DBT), image characteristics of projection views and reconstructed volume are different and both have the advantage of detecting breast masses, e.g. reconstructed volume mitigates a tissue overlap, while projection views have less reconstruction blur artifacts. In this paper, an improve...

journal_title：Physics in medicine and biology

authors： Kim DH,Kim ST,Ro YM

更新日期：2015-11-21 00:00:00

abstract：:Ion chamber dosimetry requires a high degree of precision, at all steps within the dosimetric process, in order to ensure accurate dose measurements. This work presents a novel technique for ion chamber volume determination and quality assurance, using micro-computed tomography (micro-CT). Four nominally identical Exr...

journal_title：Physics in medicine and biology

authors： McNiven AL,Umoh J,Kron T,Holdsworth DW,Battista JJ

更新日期：2008-09-21 00:00:00

abstract：:Inverse treatment planning in intensity modulated particle therapy (IMPT) with scanned carbon-ion beams is currently based on the optimization of RBE-weighted dose to satisfy requirements of target coverage and limited toxicity to organs-at-risk (OARs) and healthy tissues. There are many feasible IMPT plans that meet ...

journal_title：Physics in medicine and biology

authors： Burigo LN,Ramos-Méndez J,Bangert M,Schulte RW,Faddegon B

更新日期：2019-01-04 00:00:00

abstract：:Optically stimulated luminescent dosimeters (OSLDs) are becoming increasingly popular for measuring an absorbed dose in clinical radiotherapy. OSLDs have known energy dependence, and this is accounted for by either calibrating the OSLD with a specific nominal energy, or using a standard energy correction factor to acc...

journal_title：Physics in medicine and biology

authors： Scarboro SB,Followill DS,Kerns JR,White RA,Kry SF

更新日期：2012-05-07 00:00:00

abstract：:A novel digital x-ray detector has been assembled. The imaging system is based on a phosphor-coated charge-coupled device (CCD) obtained by direct deposition of a gadolinium oxysulphide scintillator onto the detector surface. The modulation transfer function has been measured along the two directions of the digital co...

journal_title：Physics in medicine and biology

authors： Gambaccini M,Taibi A,Del Guerra A,Marziani M,Tuffanelli A

更新日期：1996-12-01 00:00:00

abstract：:Measurements have been made using an air sampler to measure airborne radioactivity produced during the routine handling of large activities of technetium-99m, iodine-125 and iodine-131. The results indicate that 99Tcm can be safely handled in environments without direct exhaust of the ventilated air but that 125I and ...

journal_title：Physics in medicine and biology

authors： Eadie AS,Horton PW,Hilditch TE

更新日期：1980-11-01 00:00:00

abstract：:A variable Jacobian and weighted backprojection algorithm, used for medical CT, was adapted to perform CT reconstructions on data obtained with a dental panoramic x-ray unit. A detector array, fitted to the unit for the purpose of acquiring digital panoramic radiographs, was used to collect the data. Compensations wer...

journal_title：Physics in medicine and biology

authors： Lee MD,Waggener RG,McDavid WD,Dove SB,Welander U,Tronje G

更新日期：1992-12-01 00:00:00

abstract：:The MRI accelerator, a combination of a 6 MV linear accelerator with a 1.5 T MRI, facilitates continuous patient anatomy updates regarding translations, rotations and deformations of targets and organs at risk. Accounting for these demands high speed, online intensity-modulated radiotherapy (IMRT) re-optimization. In ...

journal_title：Physics in medicine and biology

authors： Bol GH,Hissoiny S,Lagendijk JJ,Raaymakers BW

更新日期：2012-03-07 00:00:00

abstract：:The University of Washington (UW) Clinical Neutron Therapy System (CNTS) has been used to treat over 3300 patients. Treatment planning for these patients is currently performed using an MV x-ray model in Pinnacle® adapted to fit measurements of fast neutron output factors, wedge factors, depth-dose and lateral profile...

journal_title：Physics in medicine and biology

authors： Moffitt GB,Wootton LS,Hårdemark B,Sandison GA,Laramore GE,Parvathaneni U,Stewart RD

更新日期：2020-08-31 00:00:00

abstract：:The reference levels and maximum permissible exposure values for magnetic fields that are currently used have been derived from basic restrictions under the assumption of upright standing body models in a standard posture, i.e. with arms laterally down and without contact with metallic objects. Moreover, if anatomical...

journal_title：Physics in medicine and biology

authors： Schmid G,Hirtl R

更新日期：2016-06-21 00:00:00

abstract：:A multimodal micro-computed tomography (CT) and multi-spectral structured light imaging (SLI) system is introduced and systematically analyzed to test its feasibility to aid in margin delineation during breast conserving surgery (BCS). Phantom analysis of the micro-CT yielded a signal-to-noise ratio of 34, a contrast ...

journal_title：Physics in medicine and biology

authors： McClatchy DM,Rizzo EJ,Meganck J,Kempner J,Vicory J,Wells WA,Paulsen KD,Pogue BW

更新日期：2017-11-10 00:00:00

abstract：:The standard Fourier metrics used for assessing image quality in computed tomography (CT) use a planar (2D) formulation of the noise equivalent quanta (NEQ) without a specific concept to manage the influence of longitudinal resolution variations, thus create a bias in the comparison of image quality for different reco...

journal_title：Physics in medicine and biology

authors： Monnin P,Viry A,Verdun FR,Racine D

更新日期：2020-06-09 00:00:00

abstract：:This study investigated the relationship between the specific absorption rate and temperature elevation in an anatomically-based model named NORMAN for exposure to radio-frequency far fields in the ICNIRP guidelines (1998 Health Phys. 74 494-522). The finite-difference time-domain method is used for analyzing the elec...

journal_title：Physics in medicine and biology

authors： Hirata A,Asano T,Fujiwara O

更新日期：2007-08-21 00:00:00

abstract：:Using Cherenkov radiation in positron emission tomography (PET) has the potential to improve the time of flight (TOF) resolution and reduce the cost of detectors. In previous studies promising TOF results were achieved when lead fluoride (PbF2) crystals were used instead of a scintillator. In this work, a whole-body P...

journal_title：Physics in medicine and biology

authors： Consuegra D,Korpar S,Križan P,Pestotnik R,Razdevšek G,Dolenec R

更新日期：2020-03-06 00:00:00

abstract：:Recently, there has been an increased interest in imaging different pulmonary disorders using PET techniques. Previous work has shown, for static PET/CT, that air content in the lung influences reconstructed image values and that it is vital to correct for this 'tissue fraction effect' (TFE). In this paper, we extend ...

journal_title：Physics in medicine and biology

authors： Holman BF,Cuplov V,Millner L,Hutton BF,Maher TM,Groves AM,Thielemans K

更新日期：2015-09-21 00:00:00

abstract：:Mean glandular dose is the quantity used for dosimetry in mammography and depends on breast-related characteristics, such as thickness and density, and on the x-ray spectrum used for breast imaging. This work aims to present an experimentally-based method to derive polyenergetic normalized glandular dose coefficients ...

journal_title：Physics in medicine and biology

authors： Santos JC,Tomal A,de Barros N,Costa PR

更新日期：2019-05-10 00:00:00

abstract：:This study presents the first observation of shear waves induced remotely within soft tissues. It was performed through the combination of a transcranial magnetic stimulation device and a permanent magnet. A physical model based on Maxwell and Navier equations was developed. Experiments were performed on a cryogel pha...

journal_title：Physics in medicine and biology

authors： Grasland-Mongrain P,Miller-Jolicoeur E,Tang A,Catheline S,Cloutier G

更新日期：2016-03-21 00:00:00

abstract：:Gas target systems have been used for decades on cyclotrons to produce radionuclides for medical imaging. However, the activity recovered from such targets is often lower than its theoretically predicted value. Past research has suggested that nuclide interactions with the walls of the target body may play a key role ...

journal_title：Physics in medicine and biology

authors： Zacchia NA,Buckley KR,Martinez GM,Ruth TJ,Martinez DM,Hoehr C

更新日期：2018-09-28 00:00:00

abstract：:Biomedical fibre-optic sensors are attractive for the measurement of physical, chemical and biochemical parameters and for spectral measurements directly performed on the patient. An overview of fibre-optic sensors for in vivo monitoring is given, with particular attention paid to the advantages that these sensors are...

journal_title：Physics in medicine and biology

authors： Mignani AG,Baldini F

更新日期：1997-05-01 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：:Several types of intravascular ultrasound (IVUS) catheters are connected to a motor at their proximal end, in order to let the catheter rotate around its length axis. However, the rotation of the distal axis tip does not follow exactly the rotation of the motor, since the catheter axis is not completely torsion-free a...

journal_title：Physics in medicine and biology

authors： Konings MK,van Leeuwen TG,Mali WP,Viergever MA

更新日期：1998-05-01 00:00:00

abstract：:Elliptically polarized magnetic fields induce higher currents in the body compared with their plane polarized counterparts. This investigation examines the degree of vector ellipticity of extremely low frequency magnetic fields (ELF-MFs) in the home, with regard to the adverse health effects reportedly associated with...

journal_title：Physics in medicine and biology

authors： Ainsbury EA,Conein E,Henshaw DL

更新日期：2005-07-07 00:00:00