A new approach to develop computer-aided detection schemes of digital mammograms.

abstract：:Clinical diffusion MRI (dMRI) is sensitive to micrometer scale spin displacements, but the image resolution is  ∼mm, so the biophysical interpretation of the signal relies on establishing appropriate subvoxel tissue models. A class of two-compartment exchange models originally proposed by Kärger have been used success...

journal_title：Physics in medicine and biology

authors： Naughton NM,Georgiadis JG

更新日期：2019-08-01 00:00:00

abstract：:Radiation therapy is an image-guided process whose success critically depends on the imaging modality used for treatment planning and the level of integration of the available imaging information. In this work, we establish a dose optimization framework for incorporating metabolic information from functional imaging m...

journal_title：Physics in medicine and biology

authors： Xing L,Cotrutz C,Hunjan S,Boyer AL,Adalsteinsson E,Spielman D

更新日期：2002-10-21 00:00:00

abstract：:In order to optimize external-beam conformal radiotherapy, patient movement during treatment must be minimized. For treatment on the upper torso, the target organs are known to move substantially due to patient respiration. This paper deals with the technical aspects of gating the radiotherapy beam synchronously with ...

journal_title：Physics in medicine and biology

authors： Kubo HD,Hill BC

更新日期：1996-01-01 00:00:00

abstract：:We developed an anatomy-guided 4D closed-form algorithm to directly reconstruct parametric images from projection data for (nearly) irreversible tracers. Conventional methods consist of individually reconstructing 2D/3D PET data, followed by graphical analysis on the sequence of reconstructed image frames. The propose...

journal_title：Physics in medicine and biology

authors： Tang J,Kuwabara H,Wong DF,Rahmim A

更新日期：2010-08-07 00:00:00

abstract：:We have developed and tested an MR-compatible gamma probe to simultaneously obtain anatomical information and functional information during surgery. The probe consists of a probe head, an optical fibre bundle and a photo-multiplier tube (PMT). The NaI(T1) scintillator contained in the probe head is connected to a 7 m ...

journal_title：Physics in medicine and biology

authors： Yamamoto S,Kuroda K,Senda M

更新日期：2004-08-07 00:00:00

abstract：:A method is presented for extraction of intra and inter fraction motion of seeds/markers within the patient from cone beam CT (CBCT) projection images. The position of the marker is determined on each projection image and fitted to a function describing the projection of a fixed point onto the imaging panel at differe...

journal_title：Physics in medicine and biology

authors： Marchant TE,Amer AM,Moore CJ

更新日期：2008-02-21 00:00:00

abstract：:In the field of regenerative medicine, there has been a growing interest in studying the combination of bone scaffolds and cells that can maximize newly formed bone. In-line phase-contrast x-ray tomography was used to image porous bone scaffolds (Skelite(©)), seeded with bone forming cells. This technique allows the q...

journal_title：Physics in medicine and biology

authors： Weber L,Langer M,Tavella S,Ruggiu A,Peyrin F

更新日期：2016-05-07 00:00:00

abstract：:Coincidence resolving time (CRT) is one of the most important physical-performance measures for positron emission tomography (PET), as reconstruction with accurate time-of-flight information enhances the lesion detectability in patient studies. Accordingly, various PET detector designs and high-performance front-end r...

journal_title：Physics in medicine and biology

authors： Park H,Lee S,Ko GB,Lee JS

更新日期：2018-12-10 00:00:00

abstract：:The in vivo electric conductivity (σ) values of tissue are essential for accurate electromagnetic simulations and specific absorption rate (SAR) assessment for applications such as thermal dose computations in hyperthermia. Currently used σ-values are mostly based on ex vivo measurements. In this study the conductivit...

journal_title：Physics in medicine and biology

authors： Balidemaj E,de Boer P,van Lier AL,Remis RF,Stalpers LJ,Westerveld GH,Nederveen AJ,van den Berg CA,Crezee J

更新日期：2016-02-21 00:00:00

abstract：:The objective of this work is to test analytical models to calculate the luminescence efficiency of Al(2)O(3):C optically stimulated luminescence detectors (OSLDs) exposed to heavy charged particles with energies relevant to space dosimetry and particle therapy. We used the track structure model to obtain an analytica...

journal_title：Physics in medicine and biology

authors： Sawakuchi GO,Yukihara EG

更新日期：2012-01-21 00:00:00

abstract：:A general theory is presented for minimizing noise in linear dimension reduction of sequences of medical images when the factors and the covariance matrix and mean of the noise are given. A dimension reduction is optimal when all diagonal elements in the covariance matrix of the noise in the signal (factor) space are ...

journal_title：Physics in medicine and biology

authors： Hermansen F,Lammertsma AA

更新日期：1995-11-01 00:00:00

abstract：:A method to measure the detector-to-object distance from the images obtained with stationary high-spatial-resolution gamma-ray cameras for in vivo studies has been developed. It exploits the shift of the imaged object in the image plane, obtained at a certain tilt of the parallel-hole collimator. A linear dependence o...

journal_title：Physics in medicine and biology

authors： Uzunov N,Bello M,Boccaccio P,Moschini G,Bollini D,de Notaristefani F

更新日期：2006-05-07 00:00:00

abstract：:A software program, SpekCalc, is presented for the calculation of x-ray spectra from tungsten anode x-ray tubes. SpekCalc was designed primarily for use in a medical physics context, for both research and education purposes, but may also be of interest to those working with x-ray tubes in industry. Noteworthy is the p...

journal_title：Physics in medicine and biology

authors： Poludniowski G,Landry G,DeBlois F,Evans PM,Verhaegen F

更新日期：2009-10-07 00:00:00

abstract：:Novel x-ray medical imaging sensors, such as photon counting detectors (PCDs) and large area CCD and CMOS cameras can involve irregular and/or sparse sampling of the detector plane. Application of such detectors to CT involves undersampling that is markedly different from the commonly considered case of sparse angular...

journal_title：Physics in medicine and biology

authors： Sisniega A,Zbijewski W,Stayman JW,Xu J,Taguchi K,Fredenberg E,Lundqvist M,Siewerdsen JH

更新日期：2016-01-07 00:00:00

abstract：:Registration of different imaging modalities such as CT, MRI, functional MRI (fMRI), positron (PET) and single photon (SPECT) emission tomography is used in many clinical applications. Determining the quality of any automatic registration procedure has been a challenging part because no gold standard is available to e...

journal_title：Physics in medicine and biology

authors： Ceylan C,van der Heide UA,Bol GH,Lagendijk JJ,Kotte AN

更新日期：2005-05-21 00:00:00

abstract：:The external radiation exposure from an overhead plume containing gamma emitting radionuclides can contribute substantial dose to the ground receptor during normal operations as well as accidental release conditions of nuclear facilities. In order to estimate the effective dose conversion coefficients (DCCs) directly,...

journal_title：Physics in medicine and biology

authors： Dey R,Patni HK,Deo Singh K,Kulkarni MS,Anand S

更新日期：2019-08-01 00:00:00

abstract：:For plane-parallel chambers used in electron dosimetry, modern dosimetry protocols recommend a cross-calibration against a calibrated cylindrical chamber. The rationale for this is the unacceptably large (up to 3-4%) chamber-to-chamber variations of the perturbation factors (pwall)Co, which have been reported for plan...

journal_title：Physics in medicine and biology

authors： Kapsch RP,Bruggmoser G,Christ G,Dohm OS,Hartmann GH,Schüle E

更新日期：2007-12-07 00:00:00

abstract：:Subharmonic contrast imaging promises to improve ultrasound-imaging quality by taking advantage of an increased contrast to tissue signal. However, acoustic pressures beyond the subharmonic generation threshold using common ultrasound pulses may induce significant contrast microbubble destruction. In this work, a chir...

journal_title：Physics in medicine and biology

authors： Zhang D,Gong Y,Gong X,Liu Z,Tan K,Zheng H

更新日期：2007-09-21 00:00:00

abstract：:We find the dose distribution that maximizes the tumour control probability (TCP) for a fixed mean tumour dose per fraction. We consider a heterogeneous tumour volume having a radiation response characterized by the linear quadratic model with heterogeneous radiosensitivity and repopulation rate that may vary in time....

journal_title：Physics in medicine and biology

authors： Levin-Plotnik D,Hamilton RJ

更新日期：2004-02-07 00:00:00

abstract：:A dedicated small-animal x-ray micro computed tomography (micro-CT) system has been developed to screen laboratory small animals such as mice and rats. The micro-CT system consists of an indirect-detection flat-panel x-ray detector with a field-of-view of 120 x 120 mm2, a microfocus x-ray source, a rotational subject ...

journal_title：Physics in medicine and biology

authors： Lee SC,Kim HK,Chun IK,Cho MH,Lee SY,Cho MH

更新日期：2003-12-21 00:00:00

abstract：:Treatment planning for proton tumor therapy requires a fast and accurate dose-calculation method. We have implemented a simplified Monte Carlo (SMC) method in the treatment planning system of the National Cancer Center Hospital East for the double-scattering beam delivery scheme. The SMC method takes into account the ...

journal_title：Physics in medicine and biology

authors： Hotta K,Kohno R,Takada Y,Hara Y,Tansho R,Himukai T,Kameoka S,Matsuura T,Nishio T,Ogino T

更新日期：2010-06-21 00:00:00

abstract：:This work aims to evaluate the predictive strength of the relative seriality, parallel and Lyman-Kutcher-Burman (LKB) normal tissue complication probability (NTCP) models regarding the incidence of radiation pneumonitis (RP), in a group of patients following lung cancer radiotherapy and also to examine their correlati...

journal_title：Physics in medicine and biology

authors： Tsougos I,Nilsson P,Theodorou K,Kjellén E,Ewers SB,Jarlman O,Lind BK,Kappas C,Mavroidis P

更新日期：2007-02-21 00:00:00

abstract：:Non-invasive evaluation of the Achilles tendon elastic properties may enhance diagnosis of tendon injury and the assessment of recovery treatments. Shear wave elastography has shown to be a powerful tool to estimate tissue mechanical properties. However, its applicability to quantitatively evaluate tendon stiffness is...

journal_title：Physics in medicine and biology

authors： Brum J,Bernal M,Gennisson JL,Tanter M

更新日期：2014-02-07 00:00:00

abstract：:Grating-based x-ray phase-contrast imaging provides three simultaneous image channels originating from a single image acquisition. While the phase signal provides direct access to the electron density in tomography, there is additional information on sub-resolutional structural information which is called dark-field s...

journal_title：Physics in medicine and biology

authors： Braig EM,Pfeiffer D,Willner M,Sellerer T,Taphorn K,Petrich C,Scholz J,Petzold L,Birnbacher L,Dierolf M,Pfeiffer F,Herzen J

更新日期：2020-09-18 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：:Monte Carlo (MC) algorithms are recognized as the most accurate methodology for patient dose assessment. For intensity-modulated radiation therapy (IMRT) delivered with dynamic multileaf collimators (DMLCs), accurate dose calculation, even with MC, is challenging. Accurate IMRT MC dose calculations require inclusion o...

journal_title：Physics in medicine and biology

authors： Siebers JV,Keall PJ,Kim JO,Mohan R

更新日期：2002-09-07 00:00:00

abstract：:Tserng and Kalhan have raised the question of the appropriate equation to use for the measurement of turnover rate in a stable-isotope study. In a comparison of glucose turnover measured with 2H-glucose and with 13C-glucose they used five apparently different equations and obtained conflicting answers. There is, howev...

journal_title：Physics in medicine and biology

authors： Wootton R,Ford GC,Cheng KN,Halliday D

更新日期：1985-10-01 00:00:00

abstract：:Accurate scatter correction is especially important for high-resolution 3D positron emission tomographies (PETs) such as high-resolution research tomograph (HRRT) due to large scatter fraction in the data. To address this problem, a fully 3D iterative scatter-corrected ordered subset expectation maximization (OSEM) in...

journal_title：Physics in medicine and biology

authors： Kim KS,Ye JC

更新日期：2011-08-07 00:00:00

abstract：:Proton therapy with active scanning beam delivery has significant advantages compared to conventional radiotherapy. However, so far only static targets have been treated in this way, since moving targets potentially lead to interplay effects. For 4D treatment planning, information on the target motion is needed to cal...

journal_title：Physics in medicine and biology

authors： Zhang Y,Boye D,Tanner C,Lomax AJ,Knopf A

更新日期：2012-04-07 00:00:00

abstract：:Ultra-wideband (UWB) electromagnetic pulses of nanosecond duration, or nanopulses, have recently been approved by the Federal Communications Commission for a number of different applications. They are also being explored for applications in biotechnology and medicine. The simulation of the propagation of a nanopulse t...

journal_title：Physics in medicine and biology

authors： Simicevic N

更新日期：2005-11-07 00:00:00