A Laplace transform pair model for spectral reconstruction.

Abstract:

:A four-parameter Laplace transform pair model, which accurately reconstructs an experimental bremsstrahlung spectrum from attenuation data, is presented. Computed spectral values with both aluminum and copper attenuators generally agree with experimental 70-kVp data to better than 2%. Reconstructed spectra at other kVp's also show good agreement with published data.

journal_name

Med Phys

journal_title

Medical physics

authors

Archer BR,Wagner LK

doi

10.1118/1.595193

subject

Has Abstract

pub_date

1982-11-01 00:00:00

pages

844-7

issue

6

eissn

0094-2405

issn

2473-4209

journal_volume

9

pub_type

杂志文章
  • Potential use of P-32 ophthalmic applicator: Monte Carlo simulations for design and dosimetry.

    abstract::Postoperative beta-irradiation after pterygium excision has been considered a valuable therapeutic procedure to reduce the recurrence rate. Recently, it was reported that beta-irradiation also substantially reduced the risk of surgical failure after glaucoma surgery. Pure beta-irradiation using a 90Sr/Y applicator has...

    journal_title:Medical physics

    pub_type: 杂志文章

    doi:10.1118/1.2896076

    authors: Park YK,Ye SJ,Kim IH,Wee WR,Kim MK,Han HS,Son KJ,Park UJ

    更新日期:2008-05-01 00:00:00

  • An automated procedure for the quality assurance of electron beam output and energy.

    abstract::In this article, we report on the development of a simple and accurate method for quality assurance of electron beam output and energy. Aluminum disks of thicknesses d(max) or d50 of the particular electron energy are positioned sequentially over a parallel-plate ion chamber and the ratio of the two signals is compare...

    journal_title:Medical physics

    pub_type: 杂志文章

    doi:10.1118/1.1688040

    authors: Woo MK,Videla NG

    更新日期:2004-05-01 00:00:00

  • Geometric studies on variable radius spiral cone-beam scanning.

    abstract::The goal is to perform geometric studies on cone-beam CT scanning along a three-dimensional (3D) spiral of variable radius. First, the background for variable radius spiral cone-beam scanning is given in the context of electron-beam CT/micro-CT. Then, necessary and sufficient conditions are proved for existence and un...

    journal_title:Medical physics

    pub_type: 杂志文章

    doi:10.1118/1.1751251

    authors: Yea Y,Zhu J,Wang G

    更新日期:2004-06-01 00:00:00

  • Computer-aided measurement of liver volumes in CT by means of geodesic active contour segmentation coupled with level-set algorithms.

    abstract:PURPOSE:Computerized liver extraction from hepatic CT images is challenging because the liver often abuts other organs of a similar density. The purpose of this study was to develop a computer-aided measurement of liver volumes in hepatic CT. METHODS:The authors developed a computerized liver extraction scheme based o...

    journal_title:Medical physics

    pub_type: 杂志文章

    doi:10.1118/1.3395579

    authors: Suzuki K,Kohlbrenner R,Epstein ML,Obajuluwa AM,Xu J,Hori M

    更新日期:2010-05-01 00:00:00

  • Dose distributions in bifurcated coronary vessels treated with catheter-based photon and beta emitters in intravascular brachytherapy.

    abstract::The dose distributions in the bifurcated vessels treated with intravascular brachytherapyline sources are complicated and depend on the bifurcation geometry consisting of a main and a branch vessel at different angles. To investigate the dosimetric effects at the bifurcation, calculations were performed on branching v...

    journal_title:Medical physics

    pub_type: 杂志文章

    doi:10.1118/1.1582813

    authors: Yue N,Roberts KB,Pfau SE,Nath R

    更新日期:2003-07-01 00:00:00

  • Dynamic multiatlas selection-based consensus segmentation of head and neck structures from CT images.

    abstract:PURPOSE:Manual delineation of head and neck (H&N) organ-at-risk (OAR) structures for radiation therapy planning is time consuming and highly variable. Therefore, we developed a dynamic multiatlas selection-based approach for fast and reproducible segmentation. METHODS:Our approach dynamically selects and weights the a...

    journal_title:Medical physics

    pub_type: 杂志文章

    doi:10.1002/mp.13854

    authors: Haq R,Berry SL,Deasy JO,Hunt M,Veeraraghavan H

    更新日期:2019-12-01 00:00:00

  • Experimental verification of a technique for predicting scattered radiation transfer: application to low photon energies.

    abstract::It is shown that predictions can be made of scatter-to-primary ratios for a variety of mammographic configurations. The different configurations can be produced by changes in source-detector distance; source-phantom distance; air gap; photon energy; phantom composition, thickness, and cross-sectional area. A detailed ...

    journal_title:Medical physics

    pub_type: 杂志文章

    doi:10.1118/1.595807

    authors: Bernstein H,Muntz EP

    更新日期:1986-11-01 00:00:00

  • What is the optimum leaf width of a multileaf collimator?

    abstract:UNLABELLED:The following question is investigated: How narrow do the leaves of a multileaf collimator have to be such that further reduction of the leaf width does not lead to physical improvements of the dose distribution. Because of the physical principles of interaction between radiation and matter, dose distributio...

    journal_title:Medical physics

    pub_type: 杂志文章

    doi:10.1118/1.1319524

    authors: Bortfeld T,Oelfke U,Nill S

    更新日期:2000-11-01 00:00:00

  • Objective characterization of GE discovery CT750 HD scanner: gemstone spectral imaging mode.

    abstract:PURPOSE:To objectively characterize the performance of the gemstone spectral imaging (GSI) mode of GE CT750 HD scanner from a user's perspective. METHODS:A regular scan protocol that approximates the adult abdomen scan protocol frequently used in the authors' institute was selected as the baseline, and a GSI protocol ...

    journal_title:Medical physics

    pub_type: 杂志文章

    doi:10.1118/1.3551999

    authors: Zhang D,Li X,Liu B

    更新日期:2011-03-01 00:00:00

  • Reliability of water proton chemical shift temperature calibration for focused ultrasound ablation therapy.

    abstract::Our purpose in this work was to assess the reliability of the calibration coefficient for magnetic resonance water proton chemical shift temperature mapping. Over a six month period, the calibration coefficient was measured 15 times in several different phantoms. A highly linear relationship between water proton chemi...

    journal_title:Medical physics

    pub_type: 杂志文章

    doi:10.1118/1.598864

    authors: Wu T,Kendell KR,Felmlee JP,Lewis BD,Ehman RL

    更新日期:2000-01-01 00:00:00

  • Signal and noise transfer properties of CMOS based active pixel flat panel imager coupled to structured CsI:Tl.

    abstract::Complementary metal-oxide-semiconductors (CMOS) active pixel sensors can be optically coupled to CsI:Tl phosphors forming a indirect active pixel flat panel imager (APFPI) for high performance medical imaging. The aim of this work is to determine the x-ray imaging capabilities of CMOS-based APFPI and study the signal ...

    journal_title:Medical physics

    pub_type: 杂志文章

    doi:10.1118/1.3036117

    authors: Arvanitis CD,Bohndiek SE,Blakesley J,Olivo A,Speller RD

    更新日期:2009-01-01 00:00:00

  • Knowledge-based segmentation of thoracic computed tomography images for assessment of split lung function.

    abstract::The assessment of differential left and right lung function is important for patients under consideration for lung resection procedures such as single lung transplantation. We developed an automated, knowledge-based segmentation algorithm for purposes of deriving functional information from dynamic computed tomography...

    journal_title:Medical physics

    pub_type: 杂志文章

    doi:10.1118/1.598898

    authors: Brown MS,Goldin JG,McNitt-Gray MF,Greaser LE,Sapra A,Li KT,Sayre JW,Martin K,Aberle DR

    更新日期:2000-03-01 00:00:00

  • Scan pattern optimization for uniform proton beam scanning.

    abstract::Magnetic beam scanning allows one to spread proton beam over the desired radiation field area, improving beam utilization and conformity to the target area. This article discusses generic scan forms for generating uniform circular and rectangular fields and establishes criteria that can be applied to optimize selected...

    journal_title:Medical physics

    pub_type: 杂志文章

    doi:10.1118/1.3158731

    authors: Anferov VA

    更新日期:2009-08-01 00:00:00

  • SU-D-211-06: The Effect of Motion in RapidArc Lung SBRT Delivery.

    abstract:PURPOSE:RapidArc is routinely used for stereotactic radiotherapy for lung cancer. While treatment dose is optimized and calculated on a static CT image, the motion of the target in conjunction with the motion of the MLC may Result in a delivered dose deviating from the planed dose. In this study, we investigate the dos...

    journal_title:Medical physics

    pub_type: 杂志文章

    doi:10.1118/1.4734660

    authors: Zou J,Yin L,Shen J,Corradetti M,Kirk M,Rengan R,Teo BK

    更新日期:2012-06-01 00:00:00

  • Investigating CT to CBCT image registration for head and neck proton therapy as a tool for daily dose recalculation.

    abstract:PURPOSE:Intensity modulated proton therapy (IMPT) of head and neck (H&N) cancer patients may be improved by plan adaptation. The decision to adapt the treatment plan based on a dose recalculation on the current anatomy requires a diagnostic quality computed tomography (CT) scan of the patient. As gantry-mounted cone be...

    journal_title:Medical physics

    pub_type: 杂志文章

    doi:10.1118/1.4908223

    authors: Landry G,Nijhuis R,Dedes G,Handrack J,Thieke C,Janssens G,Orban de Xivry J,Reiner M,Kamp F,Wilkens JJ,Paganelli C,Riboldi M,Baroni G,Ganswindt U,Belka C,Parodi K

    更新日期:2015-03-01 00:00:00

  • A comparative study of rectal dose histograms in prostate brachytherapy: some analytic and numerical results.

    abstract::A cumulative dose histogram is the graph of an integral function integrated over a domain VCR3 and is dubbed the dose-volume histogram (DVH), the dose-surface histogram (DSH) or the dose-wall histogram (DWH), depending on the dimension and structure of the region V. This paper presents a comparative study of the three...

    journal_title:Medical physics

    pub_type: 临床试验,杂志文章

    doi:10.1118/1.1852811

    authors: Song JS,Albert M,D'Amico AV,Cormack RA

    更新日期:2005-02-01 00:00:00

  • On the use of C-arm fluoroscopy for treatment planning in high dose rate brachytherapy.

    abstract::Treatment planning for brachytherapy requires the acquisition of geometrical information of the implant applicator and the patient anatomy. This is typically done using a simulator or a computed tomography scanner. In this study, we present a different method by which orthogonal images from a C-arm fluoroscopic machin...

    journal_title:Medical physics

    pub_type: 杂志文章

    doi:10.1118/1.1598851

    authors: Liu L,Bassano DA,Prasad SC,Keshler BL,Hahn SS

    更新日期:2003-09-01 00:00:00

  • Effect of MLC leaf width on treatment adaptation and accuracy for concurrent irradiation of prostate and pelvic lymph nodes.

    abstract:PURPOSE:The aim of the study was to evaluate the impact of multileaf collimator (MLC) leaf width on treatment adaptation and delivery accuracy for concurrent treatment of the prostate and pelvic lymph nodes with intensity modulated radiation therapy (IMRT). METHODS:Seventy-five kilovoltage cone beam CTs (KV-CBCT) from...

    journal_title:Medical physics

    pub_type: 杂志文章

    doi:10.1118/1.4803499

    authors: Shang Q,Qi P,Ferjani S,Xia P

    更新日期:2013-06-01 00:00:00

  • Detection nonuniformity measurements and corrections for cone beam transmission CT on a gamma camera.

    abstract::Cone beam transmission CT (CB-CT) improves SPECT imaging by providing high-quality attenuation maps for attenuation compensation and for correlated SPECT and CT imaging. The present work measures the detection nonuniformity for CB-CT implemented with a gamma camera, and applies nonuniformity corrections to make CB-CT ...

    journal_title:Medical physics

    pub_type: 杂志文章

    doi:10.1118/1.596838

    authors: Manglos SH,Capone RB,Bassano DA

    更新日期:1992-03-01 00:00:00

  • Eddy current disruption: effect on nuclear magnetic resonance coil impedance and power loss.

    abstract::We present a theoretical development and experimental verification of a description of power loss and sample resistance for a lossy sample in a nuclear magnetic resonance radio frequency coil for a sample geometry where the eddy current streamlines are disrupted from their usually assumed circular paths. Specifically ...

    journal_title:Medical physics

    pub_type: 杂志文章

    doi:10.1118/1.596336

    authors: Harpen MD

    更新日期:1989-09-01 00:00:00

  • Technical note: An algorithm to calculate the tissue phantom ratio from depth dose in radiosurgery.

    abstract:PURPOSE:To propose a method to calculate the tissue phantom ratio (TPR) using the depth dose and to compare the proposed method with two other methods. METHODS:An analytical dose model from Bjärngard was used to describe the depth dose and the TPR. The parameters of the model were derived from depth dose measurements,...

    journal_title:Medical physics

    pub_type: 杂志文章

    doi:10.1118/1.3570575

    authors: Ramos Garcia LI,Almansa JF

    更新日期:2011-05-01 00:00:00

  • A system for intensity modulated dose plan verification based on an experimental pencil beam kernel obtained by deconvolution.

    abstract::The number of intensity modulated radiation therapy (IMRT) procedures is continuously growing worldwide and it is necessary to develop tools for patient specific quality assurance (QA) that avoid using machine time that could be employed in treating additional patients. One way of achieving this goal is to perform a m...

    journal_title:Medical physics

    pub_type: 杂志文章

    doi:10.1118/1.2815359

    authors: Azcona JD,Burguete J

    更新日期:2008-01-01 00:00:00

  • Obtaining S values for rectangular-solid tumors inside rectangular-solid host organs.

    abstract::A method is described for obtaining S values between a tumor and its host organ for use with the MIRD formalism. It applies the point-source specific absorbed fractions for an infinite water medium, tabulated by Berger, to a rectangular solid of arbitrary dimensions which contains a rectangular tumor of arbitrary dime...

    journal_title:Medical physics

    pub_type: 杂志文章

    doi:10.1118/1.596732

    authors: Stinchcomb TG,Durham JS,Fisher DR

    更新日期:1991-05-01 00:00:00

  • Performance characteristics of an orthovoltage x-ray therapy machine.

    abstract::Performance characteristics sufficient to provide physical data base specific to the Siemen's Stabilipan 2 orthovoltage x-ray therapy machine are presented. Operating conditions covering the working range of the unit from 100 to 300 kVp are selected. Beam quality, output, the central axis depth dose, relative output f...

    journal_title:Medical physics

    pub_type: 杂志文章

    doi:10.1118/1.596016

    authors: Niroomand-Rad A,Gillin MT,Lopez F,Grimm DF

    更新日期:1987-09-01 00:00:00

  • Characterization of the homogeneous tissue mixture approximation in breast imaging dosimetry.

    abstract:PURPOSE:To compare the estimate of normalized glandular dose in mammography and breast CT imaging obtained using the actual glandular tissue distribution in the breast to that obtained using the homogeneous tissue mixture approximation. METHODS:Twenty volumetric images of patient breasts were acquired with a dedicated...

    journal_title:Medical physics

    pub_type: 杂志文章

    doi:10.1118/1.4737025

    authors: Sechopoulos I,Bliznakova K,Qin X,Fei B,Feng SS

    更新日期:2012-08-01 00:00:00

  • An anthropomorphic torso section phantom for ultrasonic imaging.

    abstract::Using stable materials capable of mimicking any soft tissues of the human body--quantitatively with respect to speed of sound, density, and attenuation coefficient and semiquantitatively with respect to scatter--we have constructed a torso section phantom containing simulated bowel gas, kidney, kidney fat pad, liver, ...

    journal_title:Medical physics

    pub_type: 杂志文章

    doi:10.1118/1.594657

    authors: Madsen EL,Zagzebski JA,Ghilardi-Netto T

    更新日期:1980-01-01 00:00:00

  • Measured and calculated K-fluorescence effects on the MTF of an amorphous-selenium based CCD x-ray detector.

    abstract:PURPOSE:Theoretical reasoning suggests that direct conversion digital x-ray detectors based upon photoconductive amorphous-selenium (a-Se) could attain very high values of the MTF (modulation transfer function) at spatial frequencies well beyond 20 cycles mm(-1). One of the fundamental factors affecting resolution loss...

    journal_title:Medical physics

    pub_type: 杂志文章

    doi:10.1118/1.3673957

    authors: Hunter DM,Belev G,Kasap S,Yaffe MJ

    更新日期:2012-02-01 00:00:00

  • Sci-Thur AM: Planning - 10: Improved dosimetric accuracy for patient specific quality assurance using a dual-detector measurement method for cyberknife output factors.

    abstract::The measurement of output factors for small fields is challenging and can lead to large dose errors in patient treatments if corrections for detector size and scatter from high-Z material are not applied. Due to its high spatial resolution and near tissue equivalence, GAFCHROMIC® film potentially provides a correction...

    journal_title:Medical physics

    pub_type: 杂志文章

    doi:10.1118/1.4740095

    authors: Vandervoort E,La Russa D,Ploquin N,Kadir IAE,Szanto J

    更新日期:2012-07-01 00:00:00

  • SPECT imaging of high energy isotopes and isotopes with high energy contaminants with rotating slat collimators.

    abstract:PURPOSE:Quantitative SPECT imaging is limited by many factors, including penetration of high energy photons through the collimator. Even small peaks of high energy yield extensive contamination in the photopeak energy window. Rotating slat collimators typically offer a 40- to 50-fold increase in geometric detection eff...

    journal_title:Medical physics

    pub_type: 杂志文章

    doi:10.1118/1.3177312

    authors: Van Holen R,Staelens S,Vandenberghe S

    更新日期:2009-09-01 00:00:00

  • Harmonic phase angle as a concentration-independent measure of nanoparticle dynamics.

    abstract:PURPOSE:The harmonic spectrum of magnetic nanoparticles contains valuable information about the quantity and environment of the particles. Harmonic amplitudes have been used to produce quantitative images and ratios of these amplitudes have been used to monitor changes in the particle environment. Harmonic phase angles...

    journal_title:Medical physics

    pub_type: 杂志文章

    doi:10.1118/1.3426294

    authors: Rauwerdink AM,Weaver JB

    更新日期:2010-06-01 00:00:00