Carbon ion therapy for ocular melanoma: planning orthogonal two-port treatment.

abstract：:The aim of this study is the evaluation of on-the-fly volume of intersection computation for system's geometry modelling in 3D PET image reconstruction. For this purpose we propose a simple geometrical model in which the cubic image voxels on the given Cartesian grid are approximated with spheres and the rectangular t...

journal_title：Physics in medicine and biology

authors： Lougovski A,Hofheinz F,Maus J,Schramm G,Will E,van den Hoff J

更新日期：2014-02-07 00:00:00

abstract：:Image reconstruction of ultrasound computed tomography based on the wave equation is able to show much more structural details than simpler ray-based image reconstruction methods. However, to invert the wave-based forward model is computationally demanding. To address this problem, we develop an efficient fully learne...

journal_title：Physics in medicine and biology

authors： Zhao W,Wang H,Gemmeke H,van Dongen KWA,Hopp T,Hesser J

更新日期：2020-11-27 00:00:00

abstract：:In order to analyse the respective roles of ion concentration and fractional volume of the interstitial compartment as determinants of the impedance, Z, of renal medullary tissue, a model was needed in which both these factors could be varied independently. An array of blood cell suspensions ions in saline (different ...

journal_title：Physics in medicine and biology

authors： Niewiadomski W,Sadowski J,Badzyńska B,Rasmussen SN

更新日期：1990-11-01 00:00:00

abstract：:The diagnosis of hepatocellular carcinoma (HCC) usually occurs at late stages in the disease when there are few effective treatment options. The measurement of the concentration of tumour markers in the serum of patients is a complementary tool frequently used for the interpretation of diagnostic imaging results. It i...

journal_title：Physics in medicine and biology

authors： Elshemey WM,Desouky OS,Mohammed MS,Elsayed AA,el-Houseini ME

更新日期：2003-09-07 00:00:00

abstract：:Fixed-pattern noise in electronic portal images (EPIs) is normally eliminated by dividing raw image data by an open-field calibration image (OFCI). However, for successful elimination, there must be exact registration between the two image sets. Any movement within the imaging system, such as that which occurs with ga...

journal_title：Physics in medicine and biology

authors： Kirby MC

更新日期：1996-11-01 00:00:00

abstract：:Accumulating evidence shows that hyperthermia improves head-and-neck cancer treatment. Over the last decade, we introduced a radiofrequency applicator, named HYPERcollar, which enables local heating also of deep locations in this region. Based on clinical experience, we redesigned the HYPERcollar for improved comfort,...

journal_title：Physics in medicine and biology

authors： Togni P,Rijnen Z,Numan WC,Verhaart RF,Bakker JF,van Rhoon GC,Paulides MM

更新日期：2013-09-07 00:00:00

abstract：:Silicon diodes have good spatial resolution, which makes them advantageous over ionization chambers for dosimetry in fields with high dose gradients. However, silicon diodes overrespond to low-energy photons, that are more abundant in scatter which increase with large fields and larger depths. We present a cavity-theo...

journal_title：Physics in medicine and biology

authors： Eklund K,Ahnesjö A

更新日期：2009-10-21 00:00:00

abstract：:All dosimetry protocols recommend the use of plane-parallel chambers for dose determination in electron beams with energies below 10-15 MeV. The protocols have assumed chamber perturbation effects to be negligible. The new AAPM Protocol (TG39) includes a cavity replacement factor prepl that differs from unity for some...

journal_title：Physics in medicine and biology

authors： Nilsson B,Montelius A,Andreo P

更新日期：1996-04-01 00:00:00

abstract：:The analysis of (x-ray) mammograms remains qualitative, relying on the judgement of clinicians. We present a novel method to compute a quantitative, normalized measure of tissue radiodensity traversed by the primary beam incident on each pixel of a mammogram, a measure we term the standard attenuation rate (SAR). SAR ...

journal_title：Physics in medicine and biology

authors： Tromans CE,Cocker MR,Brady SM

更新日期：2012-10-21 00:00:00

abstract：:The poor agreement in the photon calibrations of tissue-equivalent ionisation chambers between different participants in two major neutron dosimetry intercomparisons is noted. The methods of converting measurements made with a calibrated secondary standard exposure meter to the absorbed dose in the wall of a tissue-eq...

journal_title：Physics in medicine and biology

authors： Williams JR,Greening JR

更新日期：1980-03-01 00:00:00

abstract：:The aim of the study is to verify the fundamental assumption in the monitor source method, i.e. uniform fractional count loss across the field of view (FOV), and to introduce a revised monitor source method for SPECT deadtime correction that minimally interferes with the clinical protocol. SPECT images of non-uniform ...

journal_title：Physics in medicine and biology

authors： Siman W,Silosky M,Kappadath SC

更新日期：2015-02-07 00:00:00

abstract：:Measurement of the dielectric properties of ocular tissues up to 110 GHz was performed by the coaxial probe method. A coaxial sensor was fabricated to allow the measurement of small amounts of biological tissues. Four-standard calibration was applied in the dielectric property measurement to obtain more accurate data ...

journal_title：Physics in medicine and biology

authors： Sasaki K,Isimura Y,Fujii K,Wake K,Watanabe S,Kojima M,Suga R,Hashimoto O

更新日期：2015-08-21 00:00:00

abstract：:Non-invasively reconstructing the cardiac transmembrane potentials (TMPs) from body surface potentials can act as a regression problem. The support vector regression (SVR) method is often used to solve the regression problem, however the computational complexity of the SVR training algorithm is usually intensive. In t...

journal_title：Physics in medicine and biology

authors： Jiang M,Zhang H,Zhu L,Cao L,Wang Y,Xia L,Gong Y

更新日期：2015-04-21 00:00:00

abstract：:An experimental determination of the energy correction factor for alanine/paraffin pellets in the 192Ir spectrum at varying distances from the source is presented. Alanine dosimeters were irradiated in water under full scatter conditions with a high dose rate (HDR) 192Ir source (Flexisource), using a dedicated holder....

journal_title：Physics in medicine and biology

authors： Schaeken B,Cuypers R,Goossens J,Van den Weyngaert D,Verellen D

更新日期：2011-10-21 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：:Oxygen ([Formula: see text]) ions are a potential alternative to carbon ions in ion beam therapy. Their enhanced linear energy transfer indicates a higher relative biological effectiveness and a reduced oxygen enhancement ratio. Due to the limited availability of [Formula: see text] ion beams, Monte Carlo (MC) transpo...

journal_title：Physics in medicine and biology

authors： Resch AF,Fuchs H,Georg D

更新日期：2017-09-05 00:00:00

abstract：:Although x-ray mammography is widely developed for breast tumour detection, it suffers from spatial superposition in its two-dimensional (2D) representation of a three-dimensional (3D) breast structure. Accordingly, 3D breast imaging, such as cone-beam computed tomography (CT), arises at the historic moment. In this p...

journal_title：Physics in medicine and biology

authors： Chen Z,Ning R

更新日期：2003-07-21 00:00:00

abstract：:Artifacts caused by patient breathing and movement during PET data acquisition affect image quality. Respiratory gating is commonly used to gate the list-mode PET data into multiple bins over a respiratory cycle. Non-rigid registration of respiratory-gated PET images can reduce motion artifacts and preserve count stat...

journal_title：Physics in medicine and biology

authors： Li T,Zhang M,Qi W,Asma E,Qi J

更新日期：2020-07-30 00:00:00

abstract：:Task group 43 (TG43)-based dosimetry algorithms are efficient for brachytherapy dose calculation in water. However, human tissues have chemical compositions and densities different than water. Moreover, the mutual shielding effect of seeds on each other (interseed attenuation) is neglected in the TG43-based dosimetry ...

journal_title：Physics in medicine and biology

authors： Afsharpour H,Landry G,D'Amours M,Enger S,Reniers B,Poon E,Carrier JF,Verhaegen F,Beaulieu L

更新日期：2012-06-07 00:00:00

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：:Respiratory motion can blur the tomographic reconstruction of positron emission tomography or single-photon emission computed tomography (SPECT) images, which subsequently impair quantitative measurements, e.g. in the upper abdomen area. Respiratory signal phase-based gated reconstruction addresses this problem, but d...

journal_title：Physics in medicine and biology

authors： Breuilly M,Malandain G,Guglielmi J,Marsault R,Pourcher T,Franken PR,Darcourt J

更新日期：2013-04-21 00:00:00

abstract：:We assume that the data bits of a pixel in digital images can be divided into signal and noise bits. The signal bits occupy the most significant part of the pixel and the noise bits the least significant part. The signal part of each pixel are correlated while the noise parts are uncorrelated. Two statistical methods,...

journal_title：Physics in medicine and biology

authors： Chuang KS,Huang HK

更新日期：1992-02-01 00:00:00

abstract：:A circular scanning trajectory is and will likely remain a popular choice of trajectory in computed tomography (CT) imaging because it is easy to implement and control. Filtered-backprojection (FBP)-based algorithms have been developed previously for approximate and exact reconstruction of the entire image or a region...

journal_title：Physics in medicine and biology

authors： Pan X,Xia D,Zou Y,Yu L

更新日期：2004-09-21 00:00:00

abstract：:Effective use of the [Formula: see text] decay chain in targeted internal radioimmunotherapy requires the retention of both [Formula: see text] and progeny isotopes at the target site. Imaging-based pharmacokinetic tests of these pharmaceuticals must therefore separately yet simultaneously image multiple isotopes that...

journal_title：Physics in medicine and biology

authors： Robertson AKH,Ramogida CF,Rodríguez-Rodríguez C,Blinder S,Kunz P,Sossi V,Schaffer P

更新日期：2017-06-07 00:00:00

abstract：:Magnetic Resonance Electrical Impedance Tomography (MREIT) is an MRI method that enables mapping of internal conductivity and/or current density via measurements of magnetic flux density signals. The MREIT measures only the z-component of the induced magnetic flux density B = (Bx, By, Bz) by external current injection...

journal_title：Physics in medicine and biology

authors： Jeong WC,Chauhan M,Sajib SZ,Kim HJ,Serša I,Kwon OI,Woo EJ

更新日期：2014-09-07 00:00:00

abstract：:This paper contains the recommendations of the high dose rate (HDR) brachytherapy working party of the UK Institute of Physics and Engineering in Medicine (IPEM). The recommendations consist of a Code of Practice (COP) for the UK for measuring the reference air kerma rate (RAKR) of HDR (192)Ir brachytherapy sources. I...

journal_title：Physics in medicine and biology

authors： Bidmead AM,Sander T,Locks SM,Lee CD,Aird EG,Nutbrown RF,Flynn A,IPEM Working Party.

更新日期：2010-06-07 00:00:00

abstract：:Monte Carlo simulations were used to investigate large-angle x-ray scatter at design energy of 25 keV during small field of view (9.6 cm × 5 cm) differential phase contrast imaging of the breast using Talbot-Lau interferometry. Homogenous, adipose and fibroglandular breasts of uniform thickness ranging from 2 to 8 cm ...

journal_title：Physics in medicine and biology

authors： Vedantham S,Shi L,Karellas A

更新日期：2014-11-07 00:00:00

abstract：:The purpose of this study was to evaluate the impact of numerical errors caused by the floating point representation of real numbers in a GPU-based Monte Carlo code used for dose calculation in radiation oncology, and to identify situations where this type of error arises. The program used as a benchmark was bGPUMCD. ...

journal_title：Physics in medicine and biology

authors： Magnoux V,Ozell B,Bonenfant É,Després P

更新日期：2015-07-07 00:00:00

abstract：:The application of thermal modelling for hyperthermia and thermal ablation is severely hampered by lack of information about perfusion and vasculature. However, recently, with the advent of sophisticated angiography and dynamic contrast enhanced (DCE) imaging techniques, it has become possible to image small vessels a...

journal_title：Physics in medicine and biology

authors： Van den Berg CA,Van de Kamer JB,De Leeuw AA,Jeukens CR,Raaymakers BW,van Vulpen M,Lagendijk JJ

更新日期：2006-02-21 00:00:00

abstract：:A novel radiation targeted therapy is investigated for HER-2 positive breast cancers. The proposed concept combines two known approaches, but never used together for the treatment of advanced, relapsed or metastasized HER-2 positive breast cancers. The proposed radiation binary targeted concept is based on the anti HE...

journal_title：Physics in medicine and biology

authors： Mundy DW,Harb W,Jevremovic T

更新日期：2006-03-21 00:00:00