Dielectric properties of ocular tissues in the supercooled and frozen states.

abstract：:Reference dosimetry in the presence of a strong magnetic field is challenging. Ionisation chambers have shown to be strongly affected by magnetic fields. There is a need for robust and stable detectors in MRI-guided radiotherapy (MRIgRT). This study investigates the behaviour of the alanine dosimeter in magnetic field...

journal_title：Physics in medicine and biology

authors： Billas I,Bouchard H,Oelfke U,Shipley D,Gouldstone C,Duane S

更新日期：2020-06-03 00:00:00

abstract：:We propose a novel scintillation detector design for positron emission tomography (PET), which has depth of interaction (DOI) capability and uses a single-ended readout scheme. The DOI detector contains a pair of crystal bars segmented using sub-surface laser engraving (SSLE). The two crystal bars are optically couple...

journal_title：Physics in medicine and biology

authors： Uchida H,Sakai T,Yamauchi H,Hakamata K,Shimizu K,Yamashita T

更新日期：2016-09-21 00:00:00

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：:In response to the recognized fragility of reactor-produced (99)Mo supply, direct production of (99m)Tc via (100)Mo(p,2n)(99m)Tc reaction using medical cyclotrons has been investigated. However, due to the existence of other Molybdenum (Mo) isotopes in the target, in parallel with (99m)Tc, other technetium (Tc) radioa...

journal_title：Physics in medicine and biology

authors： Hou X,Tanguay J,Buckley K,Schaffer P,Bénard F,Ruth TJ,Celler A

更新日期：2016-01-21 00:00:00

abstract：:It has been reported that the dose effects of metallic guidewires are significant in intravascular brachytherapy (IVBT) using a beta source. The purpose of this work is to investigate the dependence of these dose effects on guidewire position. The EGS4 Monte Carlo codes were used to perform the dose calculations for t...

journal_title：Physics in medicine and biology

authors： Shih R,Hsu WL,Li XA

更新日期：2002-05-21 00:00:00

abstract：:Recent acute shortage of medical radioisotopes prompted investigations into alternative methods of production and the use of a cyclotron and ¹⁰⁰Mo(p,2n)(99m)Tc reaction has been considered. In this context, the production yields of (99m)Tc and various other radioactive and stable isotopes which will be created in the ...

journal_title：Physics in medicine and biology

authors： Celler A,Hou X,Bénard F,Ruth T

更新日期：2011-09-07 00:00:00

abstract：:In this study, the quantitative accuracy of different attenuation correction strategies presently available for the High Resolution Research Tomograph (HRRT) was investigated. These attenuation correction methods differ in reconstruction and processing (segmentation) algorithms used for generating a micro-image from m...

journal_title：Physics in medicine and biology

authors： van Velden FH,Kloet RW,van Berckel BN,Molthoff CF,de Jong HW,Lammertsma AA,Boellaard R

更新日期：2008-01-07 00:00:00

abstract：:We have developed an x-ray imaging system for in vivo four-dimensional computed tomography (4DCT) of small animals for pre-clinical lung investigations. Our customized laboratory facility is capable of high resolution in vivo imaging at high frame rates. Characterization using phantoms demonstrate a spatial resolution...

journal_title：Physics in medicine and biology

authors： Preissner M,Murrie RP,Pinar I,Werdiger F,Carnibella RP,Zosky GR,Fouras A,Dubsky S

更新日期：2018-04-20 00:00:00

abstract：:A dual-ended readout PET detector based on two Hamamatsu 16 × 16 arrays of 1 × 1 mm2 SiPMs coupled to both ends of a 25 × 25 array of 0.69 × 0.69 × 20 mm3 polished LYSOs was evaluated in terms of flood histogram, energy resolution, timing resolution, and DOI resolution. The SiPM arrays have a pitch size of 1.2 mm. Eac...

journal_title：Physics in medicine and biology

authors： Du J,Bai X,Cherry SR

更新日期：2020-08-19 00:00:00

abstract：:Nuclear emulsions of the Ilford K series, exposed to X-rays from 15 to 150 kVp and systematically underdeveloped, exhibit supralinear blackness--exposure curves ranging from 1- to 4-hit in character, and whose shape is the same at all excitation voltages. Processing can be so adjusted that the curve shape is well repr...

journal_title：Physics in medicine and biology

authors： Katz R,Pennington EC

更新日期：1978-11-01 00:00:00

abstract：:Biomechanical model based deformable image registration has been widely used to account for prostate deformation in various medical imaging procedures. Biomechanical material properties are important components of a biomechanical model. In this study, the effect of incorporating tumor-specific material properties in t...

journal_title：Physics in medicine and biology

authors： Samavati N,McGrath DM,Jewett MA,van der Kwast T,Ménard C,Brock KK

更新日期：2015-01-07 00:00:00

abstract：:Recent image guidance developments for preclinical synchrotron microbeam radiotherapy represent a necessary step for future clinical translation of the technique. Image quality can be further improved using x-ray phase contrast, which is readily available at synchrotron facilities. We here describe a methodology for p...

journal_title：Physics in medicine and biology

authors： Pelliccia D,Crosbie JC,Larkin KG

更新日期：2016-08-21 00:00:00

abstract：:The purpose of this study is to calculate Pareto surfaces in multi-criteria radiation treatment planning and to analyse the dependency of the Pareto surfaces on the objective functions used for the volumes of interest. We develop a linear approach that allows us to calculate truly Pareto optimal treatment plans, and w...

journal_title：Physics in medicine and biology

authors： Craft D,Halabi T,Bortfeld T

更新日期：2005-12-21 00:00:00

abstract：:Radiochromic films are useful as dosimeters in high-precision radiotherapy owing to their high spatial resolution. However, when a particle beam is measured using a radiochromic film, the dose cannot be estimated accurately because the film darkness varies with variations in linear energy transfer (LET). This paper pr...

journal_title：Physics in medicine and biology

authors： Kawashima M,Matsumura A,Souda H,Tashiro M

更新日期：2020-06-15 00:00:00

abstract：:The coincidence time resolution (CTR) becomes a key parameter of 511 keV gamma detection in time of flight positron emission tomography (TOF-PET). This is because additional information obtained through timing leads to a better noise suppression and therefore a better signal to noise ratio in the reconstructed image. ...

journal_title：Physics in medicine and biology

authors： Nemallapudi MV,Gundacker S,Lecoq P,Auffray E,Ferri A,Gola A,Piemonte C

更新日期：2015-06-21 00:00:00

abstract：:Radiotherapy treatment planning is associated with uncertainties. Examples are uncertainties in the tumour location due to organ movement or the inter/intra observer variability in target definition. Different approaches to incorporate uncertainties into IMRT optimization have been proposed. In this note, we point out...

journal_title：Physics in medicine and biology

authors： Unkelbach J,Oelfke U

更新日期：2006-12-07 00:00:00

abstract：:Developments in positron emission tomography (PET) technology have resulted in systems with finer detector elements designed to further improve spatial resolution. However, there is a limit to what extent reducing detector element size will improve spatial resolution in PET. The spatial resolution of PET imaging is li...

journal_title：Physics in medicine and biology

authors： Levin CS,Hoffman EJ

更新日期：1999-03-01 00:00:00

abstract：:The aim of this study was to investigate the utility of consistency metrics, such as inverse consistency, in contour-based deformable registration error analysis. Four images were acquired of the same phantom that has experienced varying levels of deformation. The deformations were simulated with deformable image regi...

journal_title：Physics in medicine and biology

authors： Bender ET,Tomé WA

更新日期：2009-09-21 00:00:00

abstract：:Intensive computation time is required to simulate images of electronic portal imaging device (EPID) using Monte Carlo (MC) technique, limiting the development of applications associated with EPID, such as mega-voltage cone-beam computed tomography (MV-CBCT). In this study, a fast, accurate simulation strategy for MV-...

journal_title：Physics in medicine and biology

authors： Shi M,Myronakis M,Jacobson M,Lehmann M,Ferguson D,Baturin P,Huber P,Fueglistaller R,Harris T,Lozano IV,Williams C,Morf D,Berbeco RI

更新日期：2020-07-06 00:00:00

abstract：:Quantification in cardiac mouse positron emission tomography (PET) imaging is limited by the imaging spatial resolution. Spillover of left ventricle (LV) myocardial activity into adjacent organs results in partial volume (PV) losses leading to underestimation of myocardial activity. A PV correction method was develope...

journal_title：Physics in medicine and biology

authors： Dumouchel T,Thorn S,Kordos M,DaSilva J,Beanlands RS,deKemp RA

更新日期：2012-07-07 00:00:00

abstract：:Reference dosimetry of photon fields is a well-established subject and currently available protocols (such as the IAEA TRS-398 and AAPM TG-51) provide methods for converting the ionization chamber (IC) reading into dose to water, provided reference conditions of charged particle equilibrium (CPE) are fulfilled. But th...

journal_title：Physics in medicine and biology

authors： Pena J,Sánchez-Doblado F,Capote R,Terrón JA,Gómez F

更新日期：2006-03-21 00:00:00

abstract：:The intra- and inter-batch accuracy and precision of MRI (polyacrylamide gelatin gel fabricated at atmospheric conditions) polymer gel dosimeters are assessed in full 3D. In the intra-batch study, eight spherical flasks were filled with the same polymer gel along with a set of test tubes that served as calibration pha...

journal_title：Physics in medicine and biology

authors： Vandecasteele J,De Deene Y

更新日期：2013-01-07 00:00:00

abstract：:We have developed deformable and durable optical tissue phantoms with a simple and well-defined microstructure including a novel combination of scatterers and a matrix material. These were developed for speckle and elastography investigations in optical coherence tomography, but should prove useful in many other field...

journal_title：Physics in medicine and biology

authors： Bisaillon CE,Lamouche G,Maciejko R,Dufour M,Monchalin JP

更新日期：2008-07-07 00:00:00

abstract：:A method was developed to quantify the intensity of tissue staining using a CCD (charge-coupled device) camera. Reflection spectra of NBT-stained (nitro-blue tetrazolium-stained) and unstained myocardium were recorded via fibre optics coupled to a CCD camera, connected to a microcomputer. The calculation of the intens...

journal_title：Physics in medicine and biology

authors： Schröder T,Koch G,Schnabel PA,Hering JP,Bretschneider HJ,Richter J,Hellige G

更新日期：1991-06-01 00:00:00

abstract：:This study aims at developing an optimization strategy for photon-beam dosimetry in magnetic fields using ionization chambers. Similar to the familiar case in the absence of a magnetic field, detectors should be selected under the criterion that their measured 2D signal profiles M(x,y) approximate the absorbed dose to...

journal_title：Physics in medicine and biology

authors： Looe HK,Delfs B,Poppinga D,Harder D,Poppe B

更新日期：2018-03-29 00:00:00

abstract：:Andreo and Benmakhlouf (2017 Phys. Med. Biol. 62 1518-32) have disputed a finding of Scott et al (2012 Phys. Med. Biol. 57 4461-76) that the variation with field-size of the response of small ion chambers and solid-state dosimeters in small megavoltage photon radiation fields can largely be attributed to density. Furt...

journal_title：Physics in medicine and biology

authors： Fenwick JD,Georgiou G,Rowbottom CG,Underwood TSA,Kumar S

更新日期：2018-10-03 00:00:00

abstract：:A new class of dose calibrator called a micro-dose calibrator, designed to measure radioactivity rates in the range between 1 kBq up to 370 kBq, has been designed and an 8 NaI(Tl)/photo multiplier tube (PMT) module prototype built to evaluate its performance. The design of the micro-dose calibrator is based on the con...

journal_title：Physics in medicine and biology

authors： Adler S,Choyke P

更新日期：2018-09-10 00:00:00

abstract：:An ultrahigh-resolution full-field optical coherence tomography (OCT) system has been developed for cellular-level imaging of biological media. The system is based on a Linnik interference microscope illuminated with a tungsten halogen lamp, associated with a high-resolution CCD camera. En face tomographic images are ...

journal_title：Physics in medicine and biology

authors： Dubois A,Moneron G,Grieve K,Boccara AC

更新日期：2004-04-07 00:00:00

abstract：:The extent to which occupational radiation exposure contributes to cancer mortality is an influence on future world energy policy. It is also a factor in deciding the level of expenditure to reduce radiation levels experienced by workers. Here we discuss some of the difficulties in analysing the situation and presen...

journal_title：Physics in medicine and biology

authors： Reissland JA,Kay P,Dolphin GW

更新日期：1976-11-01 00:00:00

abstract：:Monte Carlo simulation provides a valuable tool in performance assessment and optimization of system design parameters for PET scanners. SimSET is a popular Monte Carlo simulation toolkit that features fast simulation time, as well as variance reduction tools to further enhance computational efficiency. However, SimSE...

journal_title：Physics in medicine and biology

authors： Poon JK,Dahlbom ML,Casey ME,Qi J,Cherry SR,Badawi RD

更新日期：2015-02-07 00:00:00