Abstract:
:Peripheral doses out of field could have short and long terms biological effects on patients treated with electron beams. In this study, peripheral dose outside the applicator was measured using the 6, 10 and 18 MeV beams of an Elekta synergy linac. For these beams dose profiles were measured using EBT3 film at various depths within a solid water phantom. Measurements were performed using 6 × 6, 10 × 10, 14 × 14 and 20 × 20 cm2 applicators at gantryangles of 0°, 10° and 20° and depths of 0, 0.5, 1 cm and depth of Dmax (maximum dose) for each energy. The peripheral dose profiles were normalized to the distance of 2 cm from the edge of each field. The largest peak of the peripheral dose was observed for 18 MeV 3 cm from the outer edge of the applicator. Peak dose increased with increasing energy. Peak dose at 18 MeV electron beam was 1.6% at the surface of phantom and at the distance of 2 cm from the outer edge of the applicator when the applicator of 20 × 20 cm2 was used. Peak dose at 6 MeV electron beam was 1.15% at the same distance in the same applicator size. It was found that the peak dose decreased with increasing depth and increased with increase in field size. Also, the peak dose moved towards CAX with increase in gantry angle.In general dose to tissue out of field could be reduced using appropriate shielding for each applicator and beam energy.
journal_name
Australas Phys Eng Sci Medjournal_title
Australasian physical & engineering sciences in medicineauthors
Haghparast A,Amiri F,Yarahmadi M,Rezaei Mdoi
10.1007/s13246-018-0660-9subject
Has Abstractpub_date
2018-09-01 00:00:00pages
647-655issue
3eissn
0158-9938issn
1879-5447pii
10.1007/s13246-018-0660-9journal_volume
41pub_type
杂志文章abstract::Calculations have been performed of the kerma to radiographic film and to silicon from a number of x-ray spectra generated at 30 to 140 kV with tungsten and molybdenum targets. These results have been compared with the air-kerma values due to the same beams. It is concluded that both film and silicon can be used as pr...
journal_title:Australasian physical & engineering sciences in medicine
pub_type: 杂志文章
doi:
更新日期:1992-12-01 00:00:00
abstract::The Resonant Recognition Model (rrm) uses digital signal processing methods to investigate protein structure-function; and links the biological function of protein families to unique characteristic frequencies. The rrm originally used a single set of variables: the electron ion interaction potential (EIIP). Here the r...
journal_title:Australasian physical & engineering sciences in medicine
pub_type: 杂志文章
doi:
更新日期:1995-12-01 00:00:00
abstract::A group of 113 children with poor vision who had been referred to the Electrodiagnostic Clinic over a five year period were investigated for disease of the retina and optic pathway by electroretinography (ERG), electro-oculography (EOG) and visual evoked response (VER). The electrodiagnostic measurements were made usi...
journal_title:Australasian physical & engineering sciences in medicine
pub_type: 杂志文章
doi:10.1007/BF03178360
更新日期:2001-09-01 00:00:00
abstract::Three different air channels were constructed in solid water. These resemble upper respiratory and larynx geometry. Central-axis depth-dose distributions were measured on and beyond the distal surface of the air cavities. The measurements were made with a parallel-plate Markus ionisation chamber and TLDs for 6 and 25 ...
journal_title:Australasian physical & engineering sciences in medicine
pub_type: 杂志文章
doi:
更新日期:1996-12-01 00:00:00
abstract::Gravity associated with postural changes has a strong bearing on haemodynamics of blood flow in arteries. Its effect on stenosed cases has not been widely investigated. In the present study, variation observed in blood flow during postural changes is investigated for different conditions like standing, sleeping and he...
journal_title:Australasian physical & engineering sciences in medicine
pub_type: 杂志文章
doi:10.1007/s13246-014-0246-0
更新日期:2014-03-01 00:00:00
abstract::Lead attenuation characteristic curves are often consulted in premises radiation shielding assessments employing the non-destructive testing (NDT) method. This study developed lead attenuation characteristics mathematical models for the radionuclide Co-57. These models take into account the statistical variation of th...
journal_title:Australasian physical & engineering sciences in medicine
pub_type: 杂志文章
doi:10.1007/BF03179241
更新日期:2009-12-01 00:00:00
abstract::A 69 year old male was treated with an ablative dose of 3.7 GBq (100 mCi) of I131 for carcinoma of the thyroid and died 10 days after administration. The requirement for an autopsy and the level of radiation still present in the body necessitated the intervention of Radiation Safety Personnel to minimise support staff...
journal_title:Australasian physical & engineering sciences in medicine
pub_type: 杂志文章
doi:
更新日期:1991-06-01 00:00:00
abstract::Compression techniques are vital for efficient storage and fast transfer of medical image data. The existing compression techniques take significant amount of time for performing encoding and decoding and hence the purpose of compression is not fully satisfied. In this paper a rapid 4-D lossy compression method constr...
journal_title:Australasian physical & engineering sciences in medicine
pub_type: 杂志文章
doi:10.1007/s13246-015-0385-y
更新日期:2015-12-01 00:00:00
abstract::Regular checks on the performance of radiotherapy treatment units are essential and a variety of protocols has been published. These protocols identify that the determination of isocentre must be accurate and unambiguous since both the localization of a radiation field on a patient and positioning aids are referenced ...
journal_title:Australasian physical & engineering sciences in medicine
pub_type: 杂志文章
doi:10.1007/BF03178670
更新日期:2004-09-01 00:00:00
abstract::Transmission data for a fibre cement wallboard (villaboard) are determined for use in diagnostic shielding designs. Villaboard is found to be more attenuating than plasterboard e.g. 9 mm of villaboard is equivalent to 16 mm of plasterboard. ...
journal_title:Australasian physical & engineering sciences in medicine
pub_type: 杂志文章
doi:
更新日期:1998-09-01 00:00:00
abstract::Monte Carlo modelling of particle transport problems in medical radiation physics offers significant advantages over other techniques. Experiments can be performed without having to set up the physical situation, and "impossible" experiments can be performed, such as labelling multiple-scattered particles or simulatin...
journal_title:Australasian physical & engineering sciences in medicine
pub_type:
doi:
更新日期:1990-09-01 00:00:00
abstract::The angular distribution for electron beams produced by the Siemens KD-2 linear accelerator has been found by simulating electron transport through the scattering foils and air using two methods: Fermi-Eyges multiple Coulomb scattering calculations, and EGS4 Monte Carlo simulations. Fermi-Eyges theory gives solutions ...
journal_title:Australasian physical & engineering sciences in medicine
pub_type: 杂志文章
doi:
更新日期:1994-09-01 00:00:00
abstract::Due to large inter- and intra-patient variabilities of arterial input functions (AIFs), accurately modeling and using patient-specific AIF are very important for quantitative analysis of dynamic contrast enhanced MRI. Computer simulations were performed to evaluate and compare nine population AIF models with the Parke...
journal_title:Australasian physical & engineering sciences in medicine
pub_type: 杂志文章
doi:10.1007/s13246-018-0632-0
更新日期:2018-06-01 00:00:00
abstract::It has long been recognized that the assessment of Automatic Exposure Control (AEC) function is an important criterion in the assessment of any general radiographic x-ray installation. Of the tests commonly performed on an AEC, only Beam Quality Dependence relates intimately with the optical density produced on the re...
journal_title:Australasian physical & engineering sciences in medicine
pub_type: 杂志文章
doi:
更新日期:1997-09-01 00:00:00
abstract::In this paper, the peristaltic flow of rheologically complex physiological fluids when modelled by a non-Newtonian Casson fluid in a two-dimensional channel is considered. Of interest is the difference between peristaltic transport of Newtonian and non-Newtonian fluids. A perturbation series method of solution of the ...
journal_title:Australasian physical & engineering sciences in medicine
pub_type: 杂志文章
doi:
更新日期:2000-09-01 00:00:00
abstract::The effects of internal and external scatter on surface, build-up and depth dose characteristics simulated by Monte Carlo code EGSnrc for varying field size and SSD for a 10 MeV monoenergetic electron beam with and without an accelerator model are extensively studied in this paper. In particular, sub-millimetre surfac...
journal_title:Australasian physical & engineering sciences in medicine
pub_type: 杂志文章
doi:10.1007/BF03178710
更新日期:2005-09-01 00:00:00
abstract::Accuracy of dwell position and reproducibility of dwell time are critical in high dose rate (HDR) brachytherapy. A phantom was designed to verify dwell position and dwell time reproducibility for an Ir-192 HDR stepping source using Computed Radiography (CR). The central part of the phantom, incorporating thin alternat...
journal_title:Australasian physical & engineering sciences in medicine
pub_type: 杂志文章
doi:10.1007/s13246-012-0138-0
更新日期:2012-09-01 00:00:00
abstract::Aneurysm clips within stereotactic treatment volumes enhance spatial accuracy but perturb the dose distribution. The dose perturbations caused by a standard titanium alloy aneurysm clip (Ti6Al4V) have been measured with Gafchromic EBT film. The maximum dose perturbation was an increase of 6 % within 0.5 mm of the beam...
journal_title:Australasian physical & engineering sciences in medicine
pub_type: 杂志文章
doi:10.1007/BF03178449
更新日期:2008-03-01 00:00:00
abstract::In 2001 the ACPSEM published a position paper on quality assurance in screen film mammography which was subsequently adopted as a basis for the quality assurance programs of both the Royal Australian and New Zealand College of Radiologists (RANZCR) and of BreastScreen Australia. Since then the clinical implementation ...
journal_title:Australasian physical & engineering sciences in medicine
pub_type: 杂志文章
doi:10.1007/s13246-017-0583-x
更新日期:2017-09-01 00:00:00
abstract::Improved technology and higher fidelity are making medical simulations increasingly popular. A simulated peripheral nerve stimulator and thumb actuator has been developed for use with the SimMan Universal Patient Simulator. This device incorporates a handheld control box, a McKibben pneumatic muscle and articulated th...
journal_title:Australasian physical & engineering sciences in medicine
pub_type: 杂志文章
doi:
更新日期:2006-03-01 00:00:00
abstract::In this paper, the hemodynamic characteristics inside a physiologically correct three-dimensional LV model using fluid structure interaction scheme are examined under various heart beat conditions during early filling wave (E-wave), diastasis and atrial contraction wave (A-wave). The time dependent and incompressible ...
journal_title:Australasian physical & engineering sciences in medicine
pub_type: 杂志文章
doi:10.1007/s13246-014-0250-4
更新日期:2014-06-01 00:00:00
abstract::The risk of inducing contralateral breast (CLB) cancer in patients undergoing tangential field irradiation for the treatment of breast cancer is a serious concern in radiation oncology. A bilateral breast phantom made of wax attached onto the Alderson Rando phantom was used for studying the CLB dose for techniques usi...
journal_title:Australasian physical & engineering sciences in medicine
pub_type: 杂志文章
doi:10.1007/BF03178408
更新日期:2007-03-01 00:00:00
abstract::The aim of this study was to determine whether there is an effect of mobile phone electromagnetic field emissions on the human electroencephalograph (EEG). EEG recordings from ten awake subjects were taken during exposure to radiofrequency (RF) emissions from a mobile phone positioned behind the head. Two experimental...
journal_title:Australasian physical & engineering sciences in medicine
pub_type: 临床试验,杂志文章,随机对照试验
doi:10.1007/BF03179176
更新日期:2003-12-01 00:00:00
abstract::Thermoluminescence dosimetry (TLD) is a versatile tool for the assessment of dose from ionising radiation. The wide variety of TLD materials and their different physical forms allow the determination of different radiation qualities at dose levels from microGy to kGy. Major advantages of TL dosimeters are their small ...
journal_title:Australasian physical & engineering sciences in medicine
pub_type: 杂志文章,评审
doi:
更新日期:1994-12-01 00:00:00
abstract::The Australian Clinical Dosimetry Service (ACDS) has demonstrated the capacity to perform a basic dosimetry audit on all radiotherapy clinics across Australia. During the ACDS's three and a half year trial the majority of the audits were performed using optically stimulated luminescence dosimeters (OSLD) mailed to fac...
journal_title:Australasian physical & engineering sciences in medicine
pub_type: 杂志文章
doi:10.1007/s13246-014-0320-7
更新日期:2015-03-01 00:00:00
abstract::Conventional laser accelerated proton beam has broad energy spectra. It is not suitable for clinical use directly, so it is necessary for employing energy selection system. However, in the conventional laser accelerated proton system, the intensity of the proton beams in the low energy regime is higher than that in th...
journal_title:Australasian physical & engineering sciences in medicine
pub_type: 杂志文章
doi:10.1007/s13246-014-0292-7
更新日期:2014-12-01 00:00:00
abstract::Post installation acceptance testing is vital to demonstrate that the equipment meets the vendor's specification and is suitable for clinical studies. The test procedures described in the NEMA NU 2-2001 document form the basis of vendor performance specifications of PET scanners and hence are also appropriate for acce...
journal_title:Australasian physical & engineering sciences in medicine
pub_type: 杂志文章
doi:10.1007/s13246-010-0016-6
更新日期:2010-06-01 00:00:00
abstract::The effective energy of diagnostic X-rays is important for quality assurance (QA) and quality control (QC). However, the half-value layer (HVL), which is necessary to evaluate the effective energy, is not ubiquitously monitored because ionization-chamber dosimetry is time-consuming and complicated. To verify the appli...
journal_title:Australasian physical & engineering sciences in medicine
pub_type: 杂志文章
doi:10.1007/BF03178625
更新日期:2009-03-01 00:00:00
abstract::The accuracy of a computed tomography (CT)-relative electron density (RED) curve may have an indirect impact on the accuracy of dose calculation by a treatment planning system (TPS). This effect has not been previously quantified for input of different CT-RED curves from different CT-scan units in the Monaco TPS. This...
journal_title:Australasian physical & engineering sciences in medicine
pub_type: 杂志文章
doi:10.1007/s13246-019-00745-6
更新日期:2019-06-01 00:00:00
abstract::Numerical simulation is performed to demonstrate that hemodynamic factors are significant determinants for the development of a vascular pathology. Experimental measurements by particle image velocimetry are carried out to validate the credibility of the computational approach. We present a study for determining compl...
journal_title:Australasian physical & engineering sciences in medicine
pub_type: 杂志文章
doi:10.1007/s13246-010-0050-4
更新日期:2010-12-01 00:00:00