Abstract:
:The quality of phantom materials is crucial for accurate dosimetry in radiotherapy. A wide range of factors such as density, electron density and elemental composition can influence the radiation properties, and hence the absorbed dose, of materials. New materials can be tested by direct measurements which requires considerable time and the availability of relatively large amounts of the material. Alternatively, the dosimetric properties of a proposed phantom material can be compared to those of water or tissue using Monte Carlo calculations. The aim of this study was to evaluate the use of a Monte Carlo technique for the investigation of the water/tissue equivalence of phantom materials. The material used for this investigation was Standard Dosimetry Agarose (SDA) gel, which is useful in MRI dosimetry. Depth doses in gel and water were calculated for mono-energetic electron beams of 6, 12 and 20 MeV, and photon beams of 60 keV and 6 MV. For each radiation quality the depth dose distributions are in close agreement.
journal_name
Australas Phys Eng Sci Medjournal_title
Australasian physical & engineering sciences in medicineauthors
Keall P,Kron T,Hoban Psubject
Has Abstractpub_date
1993-09-01 00:00:00pages
125-8issue
3eissn
0158-9938issn
1879-5447journal_volume
16pub_type
杂志文章abstract::Bicoherence analysis is applied to electromyogram (EMG) data for the vastus lateralis quadriceps muscle of 18 adult male subjects for isometric knee extension exercise. Bicoherence spectra display ridge-like features that are indicative of deterministic chaotic behaviour and similar to those reported for normal electr...
journal_title:Australasian physical & engineering sciences in medicine
pub_type: 临床试验,杂志文章
doi:10.1007/BF03178691
更新日期:2003-03-01 00:00:00
abstract::The performance of an image registration (IR) software was evaluated for automatically detecting known errors simulated through the movement of ExactCouch using an onboard imager. Twenty-seven set-up errors (11 translations, 10 rotations, 6 translation and rotation) were simulated by introducing offset up to ± 15 mm i...
journal_title:Australasian physical & engineering sciences in medicine
pub_type: 杂志文章
doi:10.1007/s13246-012-0158-9
更新日期:2012-09-01 00:00:00
abstract::The knowledge of radiation dose at all points of interest within a patient's body is essential for the evaluation of treatment plans and for the judicious selection of the best one from among a set of competing plans. This paper discusses the physical and geometric aspects of radiation dose distribution calculations n...
journal_title:Australasian physical & engineering sciences in medicine
pub_type: 杂志文章
doi:
更新日期:1989-12-01 00:00:00
abstract::Fractal dimension has been proposed as a useful method for characterizing medical images. The fractal dimension is calculated from the average radial power spectrum of the image. However, simpler methods of calculation have been proposed. This paper examines a very simple and easily implemented method which has been p...
journal_title:Australasian physical & engineering sciences in medicine
pub_type: 杂志文章
doi:
更新日期:1991-09-01 00:00:00
abstract::Radiochromic film is a self developing two-dimensional dosimeter system that is widely used in radiotherapy. Since its development some 40 years ago many improvements have been made; however the sensitivity can vary across the film and a non-linear dose response remains. The former can be addressed using a double expo...
journal_title:Australasian physical & engineering sciences in medicine
pub_type: 杂志文章
doi:10.1007/s13246-011-0067-3
更新日期:2011-06-01 00:00:00
abstract::The measurement of absorbed dose to water in a solid-phantom may require a conversion factor because it may not be radiologically equivalent to water. One phantom developed for the use of dosimetry is a solid water, RW3 white-polystyrene material by IBA. This has a lower mass-energy absorption coefficient than water d...
journal_title:Australasian physical & engineering sciences in medicine
pub_type: 杂志文章
doi:10.1007/s13246-011-0102-4
更新日期:2011-12-01 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::In recent years, the use of gold nanoparticles in radiation therapy has been introduced as a new approach in radiotherapy. The aim of this study is to investigate the effect of gold nanoparticles (GNPs) in plaque brachytherapy for choroidal melanoma using Monte Carlo (MC) simulation. MCNPX code was used for simulation...
journal_title:Australasian physical & engineering sciences in medicine
pub_type: 杂志文章
doi:10.1007/s13246-017-0555-1
更新日期:2017-09-01 00:00:00
abstract::The purpose of this study was to measure skin dose using radiochromic film for two step-and-shoot IMRT fields and compare the results to the skin dose for a conventional open field. All exposures were made using a 6 MV photon beam produced by a Varian 21EX linear accelerator (Varian Medical Systems, CA, USA) equipped ...
journal_title:Australasian physical & engineering sciences in medicine
pub_type: 杂志文章
doi:10.1007/BF03178577
更新日期:2006-09-01 00:00:00
abstract::An automated computer-aided diagnosis system is developed to classify benign and malignant thyroid nodules using multi-stained fine needle aspiration biopsy (FNAB) cytological images. In the first phase, the image segmentation is performed to remove the background staining information and retain the appropriate foregr...
journal_title:Australasian physical & engineering sciences in medicine
pub_type: 杂志文章
doi:10.1007/s13246-013-0199-8
更新日期:2013-06-01 00:00:00
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journal_title:Australasian physical & engineering sciences in medicine
pub_type: 杂志文章
doi:10.1007/s13246-015-0383-0
更新日期:2015-12-01 00:00:00
abstract::Linear scaling is used to convert raw computed tomography (CT) pixel values into Hounsfield units corresponding to different tissue values. Analysis of a benchmarking study, presented here, where the same CT scan was imported into and then exported from multiple radiotherapy treatment planning systems, found inconsist...
journal_title:Australasian physical & engineering sciences in medicine
pub_type: 杂志文章
doi:10.1007/s13246-018-0651-x
更新日期:2018-09-01 00:00:00
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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 Australasian College of Physical Scientists and Engineers in Medicine (ACPSEM) radiation oncology specialty group (ROSG) formed a series of working groups in 2011 to develop recommendations for guidance of radiation oncology medical physics practice within the Australasian setting. These recommendations are intend...
journal_title:Australasian physical & engineering sciences in medicine
pub_type: 杂志文章,实务指引
doi:10.1007/s13246-015-0344-7
更新日期:2015-06-01 00:00:00
abstract::There are many examples of technology transfer from astronomy to medicine, for example algorithms for reconstructing X-ray CT images were first developed for processing radio astronomy images. In more recent times, X-ray detectors developed for the Hubble Space Telescope have been used in a fine-needle breast biopsy s...
journal_title:Australasian physical & engineering sciences in medicine
pub_type: 杂志文章
doi:10.1007/BF03178440
更新日期:2007-12-01 00:00:00
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journal_title:Australasian physical & engineering sciences in medicine
pub_type: 临床试验,杂志文章
doi:10.1007/s13246-016-0471-9
更新日期:2016-12-01 00:00:00
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journal_title:Australasian physical & engineering sciences in medicine
pub_type: 杂志文章
doi:
更新日期:1991-03-01 00:00:00
abstract::Most of the human head models used in dipole localisation research, which have been reported in the literature to date, assume a simplified cranial structure wherein the head is modelled as a set of distinct homogenous tissue compartments. The inherent inhomogeneity of the tissues has so far been ignored in these mode...
journal_title:Australasian physical & engineering sciences in medicine
pub_type: 杂志文章
doi:10.1007/BF03178283
更新日期:2001-03-01 00:00:00
abstract::The assignment of pathogenicity to variants suspected of causing an inherited retinal disease and the subsequent creation of molecular genetic reports sent to clinical geneticists and ophthalmologists has traditionally been time-consuming and subject to error and ambiguity. The purpose of this paper is to describe a c...
journal_title:Australasian physical & engineering sciences in medicine
pub_type: 杂志文章
doi:10.1007/s13246-015-0420-z
更新日期:2016-03-01 00:00:00
abstract::From the time when Roentgen and other physicists made the discoveries which led to the development of radiology, radiotherapy and nuclear medicine, medical physicists have played a pivotal role in the development of new technologies that have revolutionized the way medicine is practiced today. Medical physicists have ...
journal_title:Australasian physical & engineering sciences in medicine
pub_type:
doi:10.1007/BF03178583
更新日期:2008-06-01 00:00:00
abstract::Diamond detectors are particularly well suited for dosimetry applications in radiotherapy for reasons including near-tissue equivalence and high-spatial resolution resulting from small sensitive volumes. However, these detectors have not become commonplace due to high cost and poor availability arising from the need f...
journal_title:Australasian physical & engineering sciences in medicine
pub_type: 杂志文章
doi:10.1007/s13246-010-0040-6
更新日期:2010-12-01 00:00:00
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journal_title:Australasian physical & engineering sciences in medicine
pub_type: 杂志文章
doi:10.1007/s13246-010-0004-x
更新日期:2010-03-01 00:00:00
abstract::This paper investigates the influence of inhomogeneous head tissue conductivity on EEGs. A head model with inhomogeneity of radial and tangential conductivity is built up. Based on this model the EEG signals are calculated using the finite elements method. The results show that the inhomogeneous radial and tangential ...
journal_title:Australasian physical & engineering sciences in medicine
pub_type: 杂志文章
doi:10.1007/BF03178780
更新日期:2003-09-01 00:00:00
abstract::Bipolar disorder (BD) is a severe psychiatric disorder and has two common types: type I and type II. Early diagnosis of the subtypes is very challenging particularly in adolescence. In this study, 38 adolescents are participated including 18 patients with BD I and 20 patients with BD II. The electroencephalogram signa...
journal_title:Australasian physical & engineering sciences in medicine
pub_type: 杂志文章
doi:10.1007/s13246-015-0375-0
更新日期:2015-12-01 00:00:00
abstract::Large differences in monitor units have been observed when RadCalc, a pencil-beam-algorithm based software, is used to verify clinical electron plans from Raystation, a Monte-Carlo-algorithm based planning system. To investigate the problem, a number of clinical plans as well as test plans were created and calculated ...
journal_title:Australasian physical & engineering sciences in medicine
pub_type: 杂志文章
doi:10.1007/s13246-016-0470-x
更新日期:2016-09-01 00:00:00
abstract::The fragility of trabecular bone depends not only on the amount of bone but also on its architecture. In order to assess fragility of bone, describe changes due to age, and monitor effect of disease or treatment, it is necessary to model the physical properties of trabecular bone architecture. An important feature of ...
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::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::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::A set of computer programs to simulate diagnostic x-ray spectra has been developed according to the method of Birch and Marshall, with good agreement to published HPA data. These programs have been extended to simulate spectra generated with capacitor discharge x-ray units. The application of these programs has proved...
journal_title:Australasian physical & engineering sciences in medicine
pub_type: 杂志文章
doi:
更新日期:1989-09-01 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