Abstract:
:Projection and backprojection are operations that arise frequently in tomographic imaging. Recently, we proposed a new method for projection and backprojection, which we call distance-driven, and that offers low arithmetic cost and a highly sequential memory access pattern. Furthermore, distance-driven projection and backprojection avoid several artefact-inducing approximations characteristic of some other methods. We have previously demonstrated the application of this method to parallel and fan beam geometries. In this paper, we extend the distance-driven framework to three dimensions and demonstrate its application to cone beam reconstruction. We also present experimental results to demonstrate the computational performance, the artefact characteristics and the noise-resolution characteristics of the distance-driven method in three dimensions.
journal_name
Phys Med Bioljournal_title
Physics in medicine and biologyauthors
De Man B,Basu Sdoi
10.1088/0031-9155/49/11/024subject
Has Abstractpub_date
2004-06-07 00:00:00pages
2463-75issue
11eissn
0031-9155issn
1361-6560journal_volume
49pub_type
杂志文章abstract::In this paper we present the results of a dosimetric evaluation of a 2D ionization chamber array with the objective of its implementation for quality assurance in clinical routine. The pixel ionization chamber MatriXX (Scanditronix Wellhofer, Germany) consists of 32x32 chambers with a distance of 7.6 mm between chambe...
journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/52/4/023
更新日期:2007-02-21 00:00:00
abstract::Respiratory motion in emission tomography leads to reduced image quality. Developed correction methodology has been concentrating on the use of respiratory synchronized acquisitions leading to gated frames. Such frames, however, are of low signal-to-noise ratio as a result of containing reduced statistics. In this wor...
journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/52/17/006
更新日期:2007-09-07 00:00:00
abstract::The objective of this study was to be able to distinguish between healthy skin tissue and malignant ones, furthermore determining a unique pattern of roughness for each skin lesion by microtopographic analysis of the skin surface of Mexican patients during the period from April to October 2002. The standard technique ...
journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/50/23/008
更新日期:2005-12-07 00:00:00
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journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/49/15/005
更新日期:2004-08-07 00:00:00
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journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/1361-6560/ab2c92
更新日期:2019-08-01 00:00:00
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journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/58/21/7673
更新日期:2013-11-07 00:00:00
abstract::MRI-guided prostate biopsy in conventional closed-bore scanners requires transferring the patient outside the bore during needle insertion due to the constrained in-bore space, causing a safety hazard and limiting image feedback. To address this issue, we present our custom-made in-bore setup and software to support M...
journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/57/18/5823
更新日期:2012-09-21 00:00:00
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journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/53/13/N01
更新日期:2008-07-07 00:00:00
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pub_type: 杂志文章
doi:10.1088/1361-6560/ab3557
更新日期:2019-08-28 00:00:00
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journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/53/7/001
更新日期:2008-04-07 00:00:00
abstract::Spreadsheet templates which calculate cumulative exposures to other persons from patients to whom radioactive materials have been administered have been developed by the authors. Calculations can be based on any specified single-, bi- or tri-exponential whole-body clearance rate and a diurnal (or any other periodic) c...
journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/43/3/003
更新日期:1998-03-01 00:00:00
abstract::Histotripsy is an ultrasound ablation method that depends on the initiation of a cavitation bubble cloud to fractionate soft tissue. Although previous work has provided significant insight into the process of intrinsic threshold histotripsy, the majority of these studies have used highly focused (i.e. f-number < 0.6...
journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/1361-6560/aa54c7
更新日期:2017-02-21 00:00:00
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journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/46/4/303
更新日期:2001-04-01 00:00:00
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journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/26/1/011
更新日期:1981-01-01 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
pub_type: 杂志文章
doi:10.1088/0031-9155/41/11/007
更新日期:1996-11-01 00:00:00
abstract::Corrections for room scatter, [ksc(d, H)]RM, were derived using Monte Carlo methods for rooms of various sizes, including the brachytherapy treatment room, in which primary air kerma strength standardization of a remote afterloading microSelectron 192Ir HDR source was carried out, using a 60 cm3 spherical graphite ion...
journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/46/9/303
更新日期:2001-09-01 00:00:00
abstract::The amount of silica in the human lung may be estimated by measurement of silicon using in vivo neutron activation analysis. A pulsed, fast neutron beam, produced with a 2 MV Van de Graaff generator using the 2H + 2H reaction, was used to irradiate a Si-doped chest phantom in order to determine minimum detection limit...
journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/38/6/004
更新日期:1993-06-01 00:00:00
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journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/53/14/017
更新日期:2008-07-21 00:00:00
abstract::The Jacobian of the deformation field of elastic registration between images taken during radiotherapy is a measure of inter-fraction local deformation. The histogram of the Jacobian values (Jac) within an organ was introduced (JVH-Jacobian-volume-histogram) and first applied in quantifying parotid shrinkage. MVCTs of...
journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/56/11/008
更新日期:2011-06-07 00:00:00
abstract::Several recent reports agree that the potentially dangerous heating around extended wires or coaxial cables inside the bodycoil of a magnetic resonance imager is related to resonant effects. No quantitative description of this idea has been given so far. We analyse a simplified situation, where a straight metallic wir...
journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/47/16/312
更新日期:2002-08-21 00:00:00
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journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/35/7/005
更新日期:1990-07-01 00:00:00
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journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/60/18/7085
更新日期:2015-09-21 00:00:00
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journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/48/14/302
更新日期:2003-07-21 00:00:00
abstract::The aim of this study is to calculate realistic dose distributions that include the continuous deformation of organs and continuous motion of machine using 4D Monte Carlo methods for both volumetric modulated arc therapy and helical tomotherapy treatments. As part of a previous study, we presented a method to perform ...
journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/58/9/2807
更新日期:2013-05-07 00:00:00
abstract::In brachytherapy, plans are routinely calculated using the AAPM TG43 formalism which considers the patient as a simple water object. An accurate modeling of the physical processes considering patient heterogeneity using Monte Carlo simulation (MCS) methods is currently too time-consuming and computationally demanding ...
journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/60/13/4987
更新日期:2015-07-07 00:00:00
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journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/52/6/003
更新日期:2007-03-21 00:00:00
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journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/40/3/005
更新日期:1995-03-01 00:00:00
abstract::Ultrasound in the low megahertz frequency range is used by physiotherapists to treat a variety of conditions. The treatments reduce swelling, reduce pain and increase movement at joints. Ultrasound is now also beginning to be used to treat malignant tumours. The tumours are heated to temperatures between 42 degrees an...
journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/34/11/019
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journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/46/1/312
更新日期:2001-01-01 00:00:00
abstract::109Cd K x-ray fluorescence (XRF) measurement systems from two research centres were used to measure tibia lead content in a population (n = 530) of young adults. The group mean bone lead contents (+/-SEM) determined by McMaster University (n = 214) and the University of Maryland (n = 316) were 2.80 +/- 0.51 and 2.33 +...
journal_title:Physics in medicine and biology
pub_type: 杂志文章
doi:10.1088/0031-9155/44/9/313
更新日期:1999-09-01 00:00:00