A mathematical model of the biologically effective dose of solar UVA received by patients undergoing oral psoralen photochemotherapy for psoriasis.

abstract：:Energy and angular distributions of electron beams with different energies were simulated by Monte Carlo calculations. These beams were generated by the NOVAC7 system (Hitesys, Italy), a mobile electron accelerator specifically dedicated to intra-operative radiation therapy (IORT). The electron beam simulations were v...

journal_title：Physics in medicine and biology

authors： Pimpinella M,Mihailescu D,Guerra AS,Laitano RF

更新日期：2007-10-21 00:00:00

abstract：:The purpose of this work is to provide an evaluation of the mean glandular dose (MGD) for breast computed tomography (CT) with synchrotron radiation in an axial scanning configuration with a partial or total organ volume irradiation, for the in vivo program of breast CT ongoing at the ELETTRA facility (Trieste, Italy)...

journal_title：Physics in medicine and biology

authors： Mettivier G,Fedon C,Di Lillo F,Longo R,Sarno A,Tromba G,Russo P

更新日期：2016-01-21 00:00:00

abstract：:The absolute dose rate around beta sources for intravascular brachytherapy was measured with thin thermoluminescent (TL) dosimeters and radiochromic film. The calibration of these dosimeters was performed at the dose maximum in a 6 MeV electron beam of a linear accelerator. Compared to the values given by the manufact...

journal_title：Physics in medicine and biology

authors： Piessens M,Reynaert N

更新日期：2000-08-01 00:00:00

abstract：:An extensive study on specific absorption rate (SAR) covering 720 simulations and 15 voxel models (18-105 kg) has been performed by applying the parallel finite-difference time-domain method. High-resolution whole-body models have been irradiated with plane waves from 300 MHz to 5 GHz by applying various incoming dire...

journal_title：Physics in medicine and biology

authors： Uusitupa T,Laakso I,Ilvonen S,Nikoskinen K

更新日期：2010-02-21 00:00:00

abstract：:This paper addresses fundamental issues that underlie the interpretation of images acquired from turbid tissues by optical-coherence tomography (OCT). The attenuation and backscattering properties of freshly excised rat arteries and their dependence on the focusing and collection optics of the OCT system were measured...

journal_title：Physics in medicine and biology

authors： Schmitt JM,Knüttel A,Yadlowsky M,Eckhaus MA

更新日期：1994-10-01 00:00:00

abstract：:Mitral and aortic valve replacement is a procedure which is common in cardiac surgery. Some of these replacement valves are mechanical and contain moving metal parts. Should the patient in whom such a valve has been implanted be involved in magnetic resonance imaging, there is a possible dangerous interaction between ...

journal_title：Physics in medicine and biology

authors： Robertson NM,Diaz-Gomez M,Condon B

更新日期：2000-12-01 00:00:00

abstract：:We explore how the radioactive background from naturally occurring 176Lu affects single photon transmission imaging for lutetium orthosilicate (LSO) scintillator-based PET cameras by estimating the transmission noise equivalent count rate (NECR) including this background. Assuming a typical PET camera geometry (80 cm ...

journal_title：Physics in medicine and biology

authors： Huber JS,Moses WW,Jones WF,Watson CC

更新日期：2002-10-07 00:00:00

abstract：:Dose calculations for radiation arc therapy are traditionally performed by approximating continuous delivery arcs with multiple static beams. For 3D conformal arc treatments, the shape and weight variation per degree is usually small enough to allow arcs to be approximated by static beams separated by 5 degrees -10 de...

journal_title：Physics in medicine and biology

authors： Tang G,Earl MA,Luan S,Wang C,Cao D,Yu CX,Naqvi SA

更新日期：2008-09-07 00:00:00

abstract：:Fast calculation or simulation of the ablation zone induced by radiofrequency ablation (RFA) has a critical role in hepatic RFA planning and therapy. However, it remains challenging to approximate the ablation zone in real time, especially when more than one probe is involved in one ablation session. This paper presen...

journal_title：Physics in medicine and biology

authors： Chen R,Zhang J,Kong D,Lou Q,Lu F

更新日期：2021-01-27 00:00:00

abstract：:The Monte Carlo method is the most accurate method for radiotherapy dose calculations, if used correctly. However, any Monte Carlo dose calculation is burdened with statistical noise. In this paper, denoising of Monte Carlo dose distributions with a three-dimensional adaptive anisotropic diffusion method was investiga...

journal_title：Physics in medicine and biology

authors： Miao B,Jeraj R,Bao S,Mackie TR

更新日期：2003-09-07 00:00:00

abstract：:The purpose of this study was to examine the use of three physical image quality metrics in the calibration of an automatic exposure control (AEC) device for chest radiography with a computed radiography (CR) imaging system. The metrics assessed were signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR) and mean ...

journal_title：Physics in medicine and biology

authors： Moore CS,Wood TJ,Avery G,Balcam S,Needler L,Beavis AW,Saunderson JR

更新日期：2014-05-07 00:00:00

abstract：:As known, in cancer therapy with ion beams the relative biological effectiveness (RBE) of ions changes in the course of their propagation in tissues. Such changes are caused not only by increasing the linear energy transfer (LET) of beam particles with the penetration depth towards the Bragg peak, but also by nuclear ...

journal_title：Physics in medicine and biology

authors： Dewey S,Burigo L,Pshenichnov I,Mishustin I,Bleicher M

更新日期：2017-06-27 00:00:00

abstract：:Radiomic features achieve promising results in cancer diagnosis, treatment response prediction, and survival prediction. Our goal is to compare the handcrafted (explicitly designed) and deep learning (DL)-based radiomic features extracted from pre-treatment diffusion-weighted magnetic resonance images (DWIs) for predi...

journal_title：Physics in medicine and biology

authors： Fu J,Zhong X,Li N,Van Dams R,Lewis J,Sung K,Raldow AC,Jin J,Qi XS

更新日期：2020-04-02 00:00:00

abstract：:The x-ray exposure to patients has become a major concern in computed tomography (CT) and minimizing the radiation exposure has been one of the major efforts in the CT field. Due to plenty high-attenuation tissues in the human chest, under low-dose scan protocols, thoracic low-dose CT (LDCT) images tend to be severely...

journal_title：Physics in medicine and biology

authors： Chen Y,Yang Z,Hu Y,Yang G,Zhu Y,Li Y,Luo L,Chen W,Toumoulin C

更新日期：2012-05-07 00:00:00

abstract：:Modern effort in radiotherapy to address the challenges of tumor localization and motion has led to the development of MRI guided radiotherapy technologies. Accurate dose calculations must properly account for the effects of the MRI magnetic fields. Previous work has investigated the accuracy of a deterministic linear...

journal_title：Physics in medicine and biology

authors： Zelyak O,Fallone BG,St-Aubin J

更新日期：2017-12-14 00:00:00

abstract：:Determining a multidimensional velocity field within microscale opaque fluid flows is needed in areas such as microfluidic devices, biofluid mechanics and hemodynamics research in animal studies. The ultrasonic particle image velocimetry (EchoPIV) technique is appropriate for measuring opaque flows by taking advantage...

journal_title：Physics in medicine and biology

authors： Qian M,Niu L,Wang Y,Jiang B,Jin Q,Jiang C,Zheng H

更新日期：2010-10-21 00:00:00

abstract：:Accurate scatter correction is required to produce high-quality reconstructions of x-ray cone-beam computed tomography (CBCT) scans. This paper describes new scatter kernel superposition (SKS) algorithms for deconvolving scatter from projection data. The algorithms are designed to improve upon the conventional approac...

journal_title：Physics in medicine and biology

authors： Sun M,Star-Lack JM

更新日期：2010-11-21 00:00:00

abstract：:Incorrect prediction of skin dose in external beam radiotherapy (EBR) can have normal tissue complication such as acute skin desquamation and skin necrosis. The absorbed dose of skin should be evaluated within basal layer, placed between the epidermis and dermis layers. However, current treatment planning systems (TPS...

journal_title：Physics in medicine and biology

authors： Cheon BW,Yoo DH,Shin WG,Choi HJ,Park HJ,Kim JI,Min CH

更新日期：2019-08-14 00:00:00

abstract：:Values of W (the mean energy required to create an ion pair when a charged particle is stopped in a gas) are needed in radiation dosimetry to convert ionisation chamber current readings to absorbed dose. For neutron dosimetry the most important W values are those for protons, and this paper describes absolute measurem...

journal_title：Physics in medicine and biology

authors： Thomas DJ,Burke M

更新日期：1985-11-01 00:00:00

abstract：:IMRT delivery follows a planned leaf sequence, which is optimized before treatment delivery. However, it is hard to model real-time variations, such as respiration, in the planning procedure. In this paper, we propose a negative feedback system of IMRT delivery that incorporates real-time optimization to account for i...

journal_title：Physics in medicine and biology

authors： Lu W,Chen M,Ruchala KJ,Chen Q,Langen KM,Kupelian PA,Olivera GH

更新日期：2009-07-21 00:00:00

abstract：:In this paper we present a generalized Deep Learning-based approach for solving ill-posed large-scale inverse problems occuring in medical image reconstruction. Recently, Deep Learning methods using iterative neural networks (NNs) and cascaded NNs have been reported to achieve state-of-the-art results with respect to ...

journal_title：Physics in medicine and biology

authors： Kofler A,Haltmeier M,Schaeffter T,Kachelrieß M,Dewey M,Wald C,Kolbitsch C

更新日期：2020-07-06 00:00:00

abstract：:A new component module (CM), designated DYNVMLC, was developed to fully model the geometry of the Varian Millennium 120 leaf collimator using the BEAMnrc Monte Carlo code. The model includes details such as the leaf driving screw hole, support railing groove and leaf tips. Further modifications also allow sampling of ...

journal_title：Physics in medicine and biology

authors： Heath E,Seuntjens J

更新日期：2003-12-21 00:00:00

abstract：:Currently, energy spectra of laser accelerated proton beams are far from being monoenergetic. For their application in radiation therapy, energy selection systems using magnetic fields have been proposed to single out particles with the desired energy. These systems allow the choice of protons between a lowest and a h...

journal_title：Physics in medicine and biology

authors： Schell S,Wilkens JJ

更新日期：2009-10-07 00:00:00

abstract：:The purpose of this study was to validate the accuracy and reliability of volume measurements obtained using three-dimensional (3D) thoracoscopic ultrasound (US) imaging. Artificial "tumours" were created by injecting a liquid agar mixture into spherical moulds of known volume. Once solidified, the "tumours" were impl...

journal_title：Physics in medicine and biology

authors： Hornblower VD,Yu E,Fenster A,Battista JJ,Malthaner RA

更新日期：2007-01-07 00:00:00

abstract：:The relative stopping power (RSP) uncertainty is the largest contributor to the range uncertainty in proton therapy. The purpose of this work was to develop a systematic method that yields accurate and patient-specific RSPs by combining (1) pre-treatment x-ray CT and (2) daily proton radiography of the patient. The me...

journal_title：Physics in medicine and biology

authors： Collins-Fekete CA,Brousmiche S,Hansen DC,Beaulieu L,Seco J

更新日期：2017-08-03 00:00:00

abstract：:EEG interictal epileptiform discharges in temporal lobe epilepsy are associated with magnetic fields. The maxima of magnetic spikes recorded over the spherical portions of the head appear fairly symmetric, whereas those over the lower temporal region often have irregular shapes. Furthermore, their magnitude is often u...

journal_title：Physics in medicine and biology

authors： Rose DF,Sato S,Smith PD,White J

更新日期：1987-01-01 00:00:00

abstract：:Clinical cerebral blood flow (CBF) maps generated through dynamic- susceptibility contrast (DSC) magnetic resonance (MR) perfusion imaging are currently cross-calibrated with PET studies. The cross-calibration is achieved by rescaling the MR CBF values so that normal white matter CBF corresponds to 22 ml/100 g/min. Ex...

journal_title：Physics in medicine and biology

authors： Chen JJ,Frayne R,Smith MR

更新日期：2005-03-21 00:00:00

abstract：:Recently, a new family of low-cost x-radiation detectors have been developed, based on semiconducting polymer diodes, which are easy to process, mechanically flexible, relatively inexpensive, and able to cover large areas. To test their potential for radiotherapy applications such as beam monitors or dosimeters, as an...

journal_title：Physics in medicine and biology

authors： Mills CA,Chan YF,Intaniwet A,Shkunov M,Nisbet A,Keddie JL,Sellin PJ

更新日期：2013-07-07 00:00:00

abstract：:Therapy with helium ions is currently receiving significantly increasing interest because helium ions have a sharper penumbra than protons and undergo less fragmentation than carbon ions and thus require less complicated dose calculations. For any ion of interest in hadron therapy, the accuracy of dose delivery is lim...

journal_title：Physics in medicine and biology

authors： Ozoemelam I,van der Graaf E,Brandenburg S,Dendooven P

更新日期：2019-12-05 00:00:00

abstract：:Analytic solutions to the time-dependent multiregion bioheat equation are evaluated numerically for cartesian and spherical models. Principle and alternate branch contributions to the solutions are examined. The calculations include a parametric investigation and analyses of temperature behaviour in idealised upper th...

journal_title：Physics in medicine and biology

authors： Durkee JW Jr,Antich PP,Lee CE

更新日期：1990-07-01 00:00:00