Contactless remote induction of shear waves in soft tissues using a transcranial magnetic stimulation device.

abstract：:Most solid-state detectors, including 3D dosimeters, show lower signal in the Bragg peak than expected, a process termed quenching. The purpose of this study was to investigate how variation in chemical composition of a recently developed radiochromic, silicone-based 3D dosimeter influences the observed quenching in p...

journal_title：Physics in medicine and biology

authors： Høye EM,Skyt PS,Balling P,Muren LP,Taasti VT,Swakoń J,Mierzwińska G,Rydygier M,Bassler N,Petersen JB

更新日期：2017-02-21 00:00:00

abstract：:Prompt gamma (PG) imaging is widely investigated for spot-by-spot in vivo range verification for proton therapy. Previous studies pointed out that the accuracy of prompt gamma imaging is affected by the statistics (number of protons delivered per pencil beam) of the proton beams and the conformity between prompt gamma...

journal_title：Physics in medicine and biology

authors： Tian L,Landry G,Dedes G,Pinto M,Kamp F,Belka C,Parodi K

更新日期：2020-04-29 00:00:00

abstract：:The bone mineral density (BMD), ultrasound velocity (UV) and attenuation were examined in sixteen matched sets of human patellae and calcanei. For the sixteen calcanei, BMD was strongly correlated with all ultrasound parameters. Calcaneal UV appeared to be inferior to attenuation in the ability to predict BMD. For the...

journal_title：Physics in medicine and biology

authors： Han SM,Davis J

更新日期：1997-10-01 00:00:00

abstract：:An inverse radiation treatment planning algorithm for Sensus Healthcare's SculpturaTM electronic brachytherapy system has been designed. The algorithm makes use of simulated annealing to optimize the conformation number of the treatment plan. The highly anisotropic dose distributions produced by the SculpturaTM x-ray ...

journal_title：Physics in medicine and biology

authors： Badali DS,Vainer Y,Ellenor CW,Mitchell CR,Fishman K,Soro N,Price R,Funk T

更新日期：2021-01-11 00:00:00

abstract：:We present a new version of STIR (Software for Tomographic Image Reconstruction), an open source object-oriented library implemented in C++ for 3D positron emission tomography reconstruction. This library has been designed such that it can be used for many algorithms and scanner geometries, while being portable to var...

journal_title：Physics in medicine and biology

authors： Thielemans K,Tsoumpas C,Mustafovic S,Beisel T,Aguiar P,Dikaios N,Jacobson MW

更新日期：2012-02-21 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 fully three-dimensional PET imaging, iterative image reconstruction techniques usually outperform analytical algorithms in terms of image quality provided that an appropriate system model is used. In this study we concentrate on the calculation of an accurate system model for the YAP-(S)PET II small animal scanner,...

journal_title：Physics in medicine and biology

authors： Cecchetti M,Moehrs S,Belcari N,Del Guerra A

更新日期：2013-10-07 00:00:00

abstract：:In this paper, we investigate an off-line strategy to incorporate inter-fraction organ motion in IMRT treatment planning. It was suggested that inverse planning could be based on a probability distribution of patient geometries instead of a single snap shot. However, this concept is connected to two intrinsic problems...

journal_title：Physics in medicine and biology

authors： Unkelbach J,Oelfke U

更新日期：2004-09-07 00:00:00

abstract：:Radiotherapy treatment planning relies on the use of geometrically correct images. This paper presents a fully automatic tool for correcting MR images for the effects of B(0) inhomogeneities. The post-processing method is based on the gradient-reversal technique of Chang and Fitzpatrick (1992 IEEE Trans. Med. Imaging ...

journal_title：Physics in medicine and biology

authors： Reinsberg SA,Doran SJ,Charles-Edwards EM,Leach MO

更新日期：2005-06-07 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：:DMSA imaging is carried out in nuclear medicine to assess the level of functional renal tissue in patients. This study investigated the use of an artificial neural network to perform diagnostic classification of these scans. Using the radiological report as the gold standard, the network was trained to classify DMSA s...

journal_title：Physics in medicine and biology

authors： Wright JW,Duguid R,McKiddie F,Staff RT

更新日期：2014-04-07 00:00:00

abstract：:The aim of this study was to evaluate angiogenic compositions and tumour response in the course of neoadjuvant chemotherapy in patients with locally advanced breast cancer (LABC) using dynamic contrast-enhanced (DCE) MRI. Thirteen patients with LABC underwent serial DCE MRI during the course of chemotherapy. DCE MRI w...

journal_title：Physics in medicine and biology

authors： Chang YC,Huang CS,Liu YJ,Chen JH,Lu YS,Tseng WY

更新日期：2004-08-21 00:00:00

abstract：:The purpose of this paper for four-dimensional (4D) computed tomography (CT) is threefold. (1) A new spatiotemporal model is presented from the matrix perspective with the row dimension in space and the column dimension in time, namely the robust PCA (principal component analysis)-based 4D CT model. That is, instead o...

journal_title：Physics in medicine and biology

authors： Gao H,Cai JF,Shen Z,Zhao H

更新日期：2011-06-07 00:00:00

abstract：:Contemporary imaging modalities can now provide the surgeon with high quality three- and four-dimensional images depicting not only normal anatomy and pathology, but also vascularity and function. A key component of image-guided surgery (IGS) is the ability to register multi-modal pre-operative images to each other an...

journal_title：Physics in medicine and biology

authors： Peters TM

更新日期：2006-07-21 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：:The energy dependence of alanine/EPR dosimetry, in terms of absorbed dose-to-water for clinical 6, 10, 25 MV x-rays and 60Co gamma-rays was investigated by measurements and Monte Carlo (MC) calculations. The dose rates were traceable to the NRC primary standard for absorbed dose, a sealed water calorimetry. The electr...

journal_title：Physics in medicine and biology

authors： Zeng GG,McEwen MR,Rogers DW,Klassen NV

更新日期：2004-01-21 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：:The rationale for multi-modality imaging is to integrate the strengths of different imaging technologies while reducing the shortcomings of an individual modality. The work presented here proposes a limited-field-of-view (LFOV) SPECT reconstruction technique that can be implemented on a multi-modality MR/SPECT system ...

journal_title：Physics in medicine and biology

authors： Lee KS,Roeck WW,Gullberg GT,Nalcioglu O

更新日期：2011-02-07 00:00:00

abstract：:This work aims to develop, implement and validate a Monte Carlo (MC)-based independent dose calculation (IDC) framework to perform patient-specific quality assurance (QA) for multi-leaf collimator (MLC)-based CyberKnife® (Accuray Inc., Sunnyvale, CA) treatment plans. The IDC framework uses an XML-format treatment plan...

journal_title：Physics in medicine and biology

authors： Mackeprang PH,Vuong D,Volken W,Henzen D,Schmidhalter D,Malthaner M,Mueller S,Frei D,Stampanoni MFM,Dal Pra A,Aebersold DM,Fix MK,Manser P

更新日期：2017-12-19 00:00:00

abstract：:In this paper, we present a segmentation and classification method for thyroid follicular neoplasms based on a combination of the prior-based level set method and deep convolutional neural network. The proposed method aims to discriminate thyroid follicular adenoma (TFA) and follicular thyroid carcinoma (FTC) in ultra...

journal_title：Physics in medicine and biology

authors： Yang B,Yan M,Yan Z,Zhu C,Xu D,Dong F

更新日期：2020-11-02 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：:4D cone beam computed tomography (4DCBCT) is an emerging image guidance strategy used in radiotherapy where projections acquired during a scan are sorted into respiratory bins based on the respiratory phase or displacement. 4DCBCT reduces the motion blur caused by respiratory motion but increases streaking artefacts d...

journal_title：Physics in medicine and biology

authors： O'Brien RT,Kipritidis J,Shieh CC,Keall PJ

更新日期：2014-10-07 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：:Deformable image registration (DIR) is increasingly used in radiotherapy applications and provides the basis for a previously described model of patient-specific respiratory motion. We examine the accuracy of a DIR algorithm and a motion model with respiration-correlated CT (RCCT) images of software phantom with known...

journal_title：Physics in medicine and biology

authors： Liu F,Hu Y,Zhang Q,Kincaid R,Goodman KA,Mageras GS

更新日期：2012-05-07 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：:The dosimetric measurement and modeling of small radiation treatment fields (<2 × 2 cm2) are difficult to perform and prone to error. Measurements of small fields are often adversely influenced by the properties of the detectors used to make them. The dosimetric properties of small fields have been difficult to accura...

journal_title：Physics in medicine and biology

authors： Hundertmark B,Sterpin E,Mackie T

更新日期：2011-06-21 00:00:00

abstract：:Recent measurements of differential elastic and inelastic neutron scattering from oxygen, nitrogen and calcium at 18 less than En less than 26 MeV are presented and analysed in terms of the optical model. These data, together with earlier measurements of scattering and total cross sections, are used to construct model...

journal_title：Physics in medicine and biology

authors： Islam MS,Finlay RW,Petler JS,Rapaport J,Alarcon R,Wierzbicki J

更新日期：1988-03-01 00:00:00

abstract：:The treatment of large tumors such as sarcomas with intra-operative radiotherapy using a Mobetron is often complicated because of the limited field size of the primary collimator and the available applicators (max Ø100 mm). To circumvent this limitation a prototype rectangular applicator of 80 x 150 mm(2) was designed...

journal_title：Physics in medicine and biology

authors： Janssen RW,Faddegon BA,Dries WJ

更新日期：2008-04-21 00:00:00

abstract：:The development of alpha-emitting radiopharmaceuticals using 211At requires quantitative determination of the time-dependent nature of the 211At biodistribution. However, imaging-based methods for acquiring this information with 211At have not found wide-spread use because of its low abundance of decay emissions suita...

journal_title：Physics in medicine and biology

authors： Crawford JR,Robertson AKH,Yang H,Rodríguez-Rodríguez C,Esquinas PL,Kunz P,Blinder S,Sossi V,Schaffer P,Ruth TJ

更新日期：2018-02-21 00:00:00

abstract：:109Cd K x-ray fluorescence (XRF) measurement systems from two research centres were used to measure tibia lead content in a population (n = 530) of young adults. The group mean bone lead contents (+/-SEM) determined by McMaster University (n = 214) and the University of Maryland (n = 316) were 2.80 +/- 0.51 and 2.33 +...

journal_title：Physics in medicine and biology

authors： McNeill FE,Stokes L,Chettle DR,Kaye WE

更新日期：1999-09-01 00:00:00