Image Resolution in MicroCT: Principles and Characterization of the Quantum FX and Quantum GX Systems
|
|
- Augustine O’Neal’
- 6 years ago
- Views:
Transcription
1 T E C H N I C A L N O T E Preclinical In Vivo Imaging Authors: Ali Behrooz, Ph.D. Jen-Chieh Tseng, Ph.D. Jeff Meganck, Ph.D. PerkinElmer, Inc. Hopkinton, MA Image Resolution in MicroCT: Principles and Characterization of the Quantum FX and Quantum GX Systems Purpose Preclinical micro-computed tomography (microct, μct) systems are used in many different imaging applications. Many of these studies require imaging small anatomical structures with spatial resolutions that are sufficient to track subtle changes over the course of a longitudinal study and/or subtle changes between diseased and naïve subjects early in disease. Therefore, it is extremely important to understand the performance of in vivo imaging systems. This Technical Note describes the principles that govern 3D spatial resolution and provides a foundation for interpreting the physical performance of microct imaging systems. Using these principles, the limiting spatial resolutions of the Quantum FX and Quantum GX microct imaging systems were characterized.
2 Introduction With any in vivo imaging instrument, the goal is to create a perfect image of the object (e.g. animal, sample) being scanned. In practice, however, performance limitations and image artifacts result in an imperfect representation of the object. Many microcomputed tomography applications are intended to image small anatomical structures. Therefore, it is critically important to understand the limits of what can be visually captured in the image. This is often described in two different ways: Voxel Size: The physical size of the 3D discrete volume element ( Voxel ) in the image. Spatial Resolution: The size of the smallest object visually detectable, usually defined as the smallest space between two isolated discrete objects. Both terminologies are frequently used in the peer-reviewed scientific literature as well as in product literature. Understanding the distinction between voxel size and spatial resolution is essential to interpret data. In practice, the spatial resolution limit of every microct system is degraded by image artifacts and blur. Artifacts can include physical sources such as beam hardening (a differential absorption of X-rays based on energy in a polychromatic beam), aliasing, partial voluming, photon starvation, and undersampling. 1 Physical sources of blur include motion (both from the subject motion and mechanical motions), penumbral blur due to a finite focal spot size, and dispersion of light within the scintillator and detector. 2 Filtering properties of the reconstruction algorithms can also affect image quality and resolution. In light of these complexities, the 3D image spatial resolution can only be obtained by characterizing the imaging system. This is commonly presented as a modulation transfer function (MTF). Resolution is often thought of in terms of physical space. The simplest approach to measure MTF is often to scan a phantom which has a range of fixed line widths and determine what is visually detectable; phantoms for this purpose are commercially available. 3,7 However, the limiting resolution commonly falls between the fixed frequencies used in these phantoms. When that is needed, the MTF can be analytically characterized from the point spread function. The purpose of this study is to formally characterize resolution in the Quantum FX and Quantum GX imaging system using both the measurement-based and analytical approaches. Figure 1. Photograph of the custom built phantom to freely suspend an acrylic rod.. Methods Phantom Design Two different phantoms were used in this study: 1. To look at discrete frequencies, a bar pattern phantom (QRM GmBH; products/microct/microct_barpattern.htm) was scanned. 8 This phantom contains two separate chips with bar patterns etched into them; one chip is oriented parallel to the center of rotation and the other chip is perpendicular to the center of rotation. 2. To analytically characterize the complete MTF, a custom phantom was built to freely suspend a 1/8 acrylic cylindrical rod (McMaster Carr) within the imaging Field of View. (Figure 1) Image Acquisition and Formation Images of both phantoms were acquired on the Quantum FX and the Quantum GX instruments using the longest supported scan times: 4.5 minute scan on the Quantum FX or 57 minute scan on the Quantum GX. The imaging modes selected used bin 1 on the detector. Gain calibrations were redone prior to imaging to minimize artifacts in the final images. All images were reconstructed using a filtered back-projection algorithm with a Ram-Lak filter. A sinogram-based ring reduction filter was used to minimize rings inherent in CT scans. On the Quantum GX, a single transaxial slice was reconstructed at the best possible resolution (Figure 2A and 2B) of 4.5 μm in plane pixel size; the slice thickness selected was 36 μm. On the Quantum FX, the voxel size is directly linked to the FOV, so the smallest 5 mm FOV was used and reconstructed with an isotropic voxel size of 10 μm. 2
3 B C D A Figure 2: (A) The initial Quantum GX acquisition was acquired for a 36 mm FOV and reconstructed with a 72 µm voxel size. A single slice for a subsection of the image corresponding to the bar pattern chip oriented in a transaxial plane was then selected and reconstructed to be 4.5 µm. (B) The smallest line pair section was cropped out of this image (yellow box). (C) A summed line profile was generated for each line pair pattern; averaging was performed along an axis orthogonal to the red line for the portion between the green lines. (D) Image of the acrylic phantom reconstructed with the ring reduction algorithm applied. A B Figure 3: Quantum FX images of the (A) QRM bar pattern target reconstructed and (B) an acrylic phantom with the ring reduction algorithm applied. Direct Resolution Measurements To derive the resolution based on the bar pattern phantom, the images were imported into the image processing package Analyze (AnalyzeDirect, Overland Park, KS). A line profile plot was created by averaging multiple columns across the line pair pattern to reduce noise (Figure 2C). This data was then imported into MATLAB and a custom script was written to apply a baseline and calculate the MTF for each line pair phantom using the following equation MTF= I PEAK _ I VALLEY I PEAK +I VALLEY where I PEAK represents the mean grayscale value for all peaks and I VALLEY represents the mean grayscale value for all valleys. Analytical Characterization of Modulation Transfer Function (MTF) A Fourier-based analytical approach was developed based on previously described methods 6 to accurately characterize the spatial resolution and MTF for the entire frequency range. In this approach, the acrylic rod is automatically segmented in the 3D microct (μct) volume, and projected (averaged) along its medial axis to render a 2D projected image as depicted in (Figure 4A). This 2D image is radially binned at sub-nyquist intervals as shown in Figure 4B. The mean pixel values from the radial bins are used to produce an edge spread function (ESF), equivalent to the step response function widely used in the field of signal processing. The difference operator is applied to the ESF to arrive at the line spread function (LSF). This is conceptually equivalent to an impulse response. The fast Fourier transform of the LSF yields the MTF for the corresponding system. 3
4 A B C Figure 4: Projected 2D image of the acrylic phantom is binned to produce the edge spread function. (A) 3D image of the acrylic phantom is projected along the medial axis (z-axis) to produce a 2D projected representation of the acrylic phantom. (B) The 2D projected image is radially binned, and the pixel values in each bin are averaged to form the edge spread function. (C) The edge spread function (1D signal) is computed using the mean pixel values from the radial bins attributed to the 2D projected image. Results and Discussion MTF curves for the Quantum FX and Quantum GX imaging systems show a good match between the analytically characterized MTF curves and the measured MTF values from the bar pattern phantom (Figure 5). As expected, the limiting resolution in the Quantum GX is better than in the Quantum FX due to smaller voxel size and improved system components in Quantum GX. The smallest visually distinguishable line pair from the bar pattern target was a 15 μm line in the Quantum GX and a 50 μm in the Quantum FX. The spatial frequency correlating to 3%, 5% and 10%, three commonly used limits for the precise limiting resolution, 9 were calculated from the MTF curves analytically characterized using the acrylic phantom (Table 1). The limiting resolutions of the Quantum FX and Quantum GX are and lp/mm respectively. It should be noted that the MTF is not, in itself, a perfect metric for image characterization. Image quality is also related to the noise level in the image, so some investigators have proposed using the detective quantum efficiency metric (DQE) that accounts for both MTF and the noise power spectrum (NPS). 10 Since the purpose of this study is primarily to characterize the limiting resolution, this generalization is not strictly necessary to interpret these results. It is still important to ensure that the methods used in this study accurately represent the limiting resolution. The lp/mm at 10% MTF for the Quantum FX is comparable to the lp/mm measured using a different technique, 11 providing some reassurance that the methods used here provide a fair assessment of the performance. Table 1: Tabulated results for the limiting resolution in the MTF curve. Instrument Limiting MTF Target Limiting Res (lp/mm) Line Width (μm) FX 10% % % GX 10% % % Figure 5: Plots of the MTF curve for the (A) Quantum GX and (B) Quantum FX imaging systems analytically characterized from the acrylic rod. Asterisk marks indicate the fixed measurements taken from the bar pattern phantom. 4
5 Conclusion The limiting resolution of the Quantum GX and Quantum FX imaging systems is market leading. The theoretical limiting resolution of 9 μm in the Quantum GX and ability to visually identify a 15 μm line in a bar pattern phantom is better than any other system currently available. This resolution is quite sufficient relative to the common needs for small animal imaging applications. Small anatomical structures such as trabecular bone and small vessels can be easily resolved with the resolutions 12, 13 achieved on either imaging system. Figure 6: Images of (A) mouse inner ear structure and (B) tumor vasculature in a murine tumor model obtained using the Quantum GX. References 1. J. F. Barrett and N. Keat, Artifacts in CT: Recognition and Avoidance, RadioGraphics, pp , 24AD. 2. J. a. Seibert and J. M. Boone, X-ray imaging physics for nuclear medicine technologists. Part 2: X-ray interactions and image formation, J. Nucl. Med. Technol., vol. 33, no. 1, pp. 3 18, L. Y. Du, J. Umoh, H. N. Nikolov, S. I. Pollmann, T.-Y. Lee, and D. W. Holdsworth, A quality assurance phantom for the performance evaluation of volumetric micro-ct systems, Phys. Med. Biol., vol. 52, no. 23, pp , L. Arentsen and S. Hui, Characterization of rotating gantry micro- CT configuration for the in vivo evaluation of murine trabecular bone, Microsc. Microanal., vol. 19, pp , W. Stiller, M. Kobayashi, K. Koike, U. Stampfl, G. M. Richter, W. Semmler, and F. Kiessling, Initial Experience with a Novel Low-Dose Micro-CT System, Rofo, vol. 179, no. 7, pp , S. N. Friedman, G. S. K. Fung, J. H. Siewerdsen, and B. M. W. Tsui, A simple approach to measure computed tomography (CT) modulation transfer function (MTF) and noise-power spectrum (NPS) using the American College of Radiology (ACR) accreditation phantom, Med. Phys., vol. 40, no. 5, p , J. Rueckel, M. Stockmar, F. Pfeiffer, and J. Herzen, Spatial resolution characterization of a X-ray microct system, Appl. Radiat. Isot., vol. 94, pp , O. Langner, M. Karolczak, G. Rattmann, and W. A. Kalender, Bar and Point Test Patterns Generated by Dry-Etching for Measurement of High Spatial Resolution Micro-CT, in IFMBE Proceedings, World Congress on Medical Physics and Biomedical Engineering, S. W. Smith, The Scientist and Engineer s Guide to Digital Signal Processing, in The Scientist and Engineer s Guide to Digital Signal Processing, 1997, pp J. P. Moy, Signal-to-noise ratio and spatial resolution in x-ray electronic imagers: is the MTF a relevant parameter?, Med. Phys., vol. 27, no. 1, pp , M. U. Ghani, Z. Zhou, L. Ren, M. Wong, Y. Li, B. Zheng, K. Yang, and H. Liu, Investigation of spatial resolution characteristics of an in vivo microcomputed tomography system, Nucl. Instruments Methods Phys. Res. Sect. A Accel. Spectrometers, Detect. Assoc. Equip., vol. 807, pp , J.-C. Tseng, A. Behrooz, J. Meganck, J. Kempner, and J. Peterson, Using Quantum GX mct system to investigate bone erosion and deformation in osteoarthritis rats PerkinElmer applications notes, N. M. Das, S. Hatsell, K. Nannuru, L. Huang, X. Wen, L. Wang, L.-H. Wang, V. Idone, J. A. Meganck, A. Murphy, A. Economides, and L. Xie, In Vivo Quantitative Microcomputed Tomographic Analysis of Vasculature and Organs in a Normal and Diseased Mouse Model, PLoS One, vol. 11, no. 2, p. e , Feb PerkinElmer, Inc. 940 Winter Street Waltham, MA USA P: (800) or (+1) For a complete listing of our global offices, visit Copyright , PerkinElmer, Inc. All rights reserved. PerkinElmer is a registered trademark of PerkinElmer, Inc. All other trademarks are the property of their respective owners A_01 PKI
Quality control phantoms and protocol for a tomography system
Quality control phantoms and protocol for a tomography system Lucía Franco 1 1 CT AIMEN, C/Relva 27A O Porriño Pontevedra, Spain, lfranco@aimen.es Abstract Tomography systems for non-destructive testing
More informationBackground. Outline. Radiographic Tomosynthesis: Image Quality and Artifacts Reduction 1 / GE /
Radiographic Tomosynthesis: Image Quality and Artifacts Reduction Baojun Li, Ph.D Department of Radiology Boston University Medical Center 2012 AAPM Annual Meeting Background Linear Trajectory Tomosynthesis
More informationDigital Image Processing
Digital Image Processing SPECIAL TOPICS CT IMAGES Hamid R. Rabiee Fall 2015 What is an image? 2 Are images only about visual concepts? We ve already seen that there are other kinds of image. In this lecture
More informationEmpirical cupping correction: A first-order raw data precorrection for cone-beam computed tomography
Empirical cupping correction: A first-order raw data precorrection for cone-beam computed tomography Marc Kachelrieß, a Katia Sourbelle, and Willi A. Kalender Institute of Medical Physics, University of
More informationDevelopment and Characterization of a Flat-panel Detector-based Microtomography System
Key Engineering Materials Vols. 70-73 (004) pp. 45-51 online at http://www.scientific.net 004 Trans Tech Publications, Switzerland Citation & Copyright (to be inserted by the publisher) Development and
More informationSimulation of Mammograms & Tomosynthesis imaging with Cone Beam Breast CT images
Simulation of Mammograms & Tomosynthesis imaging with Cone Beam Breast CT images Tao Han, Chris C. Shaw, Lingyun Chen, Chao-jen Lai, Xinming Liu, Tianpeng Wang Digital Imaging Research Laboratory (DIRL),
More informationProjection and Reconstruction-Based Noise Filtering Methods in Cone Beam CT
Projection and Reconstruction-Based Noise Filtering Methods in Cone Beam CT Benedikt Lorch 1, Martin Berger 1,2, Joachim Hornegger 1,2, Andreas Maier 1,2 1 Pattern Recognition Lab, FAU Erlangen-Nürnberg
More informationAssessment of 3D performance metrics. X-ray based Volumetric imaging systems: Fourier-based imaging metrics. The MTF in CT
Assessment of 3D performance metrics D and 3D Metrics of Performance Towards Quality Index: Volumetric imaging systems X-ray based Volumetric imaging systems: CBCT/CT Tomosynthesis Samuel Richard and Ehsan
More informationCT NOISE POWER SPECTRUM FOR FILTERED BACKPROJECTION AND ITERATIVE RECONSTRUCTION
CT NOISE POWER SPECTRUM FOR FILTERED BACKPROJECTION AND ITERATIVE RECONSTRUCTION Frank Dong, PhD, DABR Diagnostic Physicist, Imaging Institute Cleveland Clinic Foundation and Associate Professor of Radiology
More informationFluorescence Tomography Source Reconstruction and Analysis
TECHNICAL NOTE Pre-clinical in vivo imaging Fluorescence Tomography Source Reconstruction and Analysis Note: This Technical Note is part of a series for Fluorescence Imaging Tomography (FLIT). The user
More informationOptimization of CT Simulation Imaging. Ingrid Reiser Dept. of Radiology The University of Chicago
Optimization of CT Simulation Imaging Ingrid Reiser Dept. of Radiology The University of Chicago Optimization of CT imaging Goal: Achieve image quality that allows to perform the task at hand (diagnostic
More informationSpiral CT. Protocol Optimization & Quality Assurance. Ge Wang, Ph.D. Department of Radiology University of Iowa Iowa City, Iowa 52242, USA
Spiral CT Protocol Optimization & Quality Assurance Ge Wang, Ph.D. Department of Radiology University of Iowa Iowa City, Iowa 52242, USA Spiral CT Protocol Optimization & Quality Assurance Protocol optimization
More informationPhase-Contrast Imaging and Tomography at 60 kev using a Conventional X-ray Tube
Phase-Contrast Imaging and Tomography at 60 kev using a Conventional X-ray Tube T. Donath* a, F. Pfeiffer a,b, O. Bunk a, W. Groot a, M. Bednarzik a, C. Grünzweig a, E. Hempel c, S. Popescu c, M. Hoheisel
More informationDUE to beam polychromacity in CT and the energy dependence
1 Empirical Water Precorrection for Cone-Beam Computed Tomography Katia Sourbelle, Marc Kachelrieß, Member, IEEE, and Willi A. Kalender Abstract We propose an algorithm to correct for the cupping artifact
More informationTomographic Reconstruction
Tomographic Reconstruction 3D Image Processing Torsten Möller Reading Gonzales + Woods, Chapter 5.11 2 Overview Physics History Reconstruction basic idea Radon transform Fourier-Slice theorem (Parallel-beam)
More informationDevelopments in Dimensional Metrology in X-ray Computed Tomography at NPL
Developments in Dimensional Metrology in X-ray Computed Tomography at NPL Wenjuan Sun and Stephen Brown 10 th May 2016 1 Possible factors influencing XCT measurements Components Influencing variables Possible
More informationImage Acquisition Systems
Image Acquisition Systems Goals and Terminology Conventional Radiography Axial Tomography Computer Axial Tomography (CAT) Magnetic Resonance Imaging (MRI) PET, SPECT Ultrasound Microscopy Imaging ITCS
More informationCentral Slice Theorem
Central Slice Theorem Incident X-rays y f(x,y) R x r x Detected p(, x ) The thick line is described by xcos +ysin =R Properties of Fourier Transform F [ f ( x a)] F [ f ( x)] e j 2 a Spatial Domain Spatial
More information18th World Conference on Nondestructive Testing, April 2012, Durban, South Africa
18th World Conference on Nondestructive Testing, 16-20 April 2012, Durban, South Africa TOWARDS ESTABLISHMENT OF STANDARDIZED PRACTICE FOR ASSESSMENT OF SPATIAL RESOLUTION AND CONTRAST OF INTERNATIONAL
More informationMEDICAL EQUIPMENT: COMPUTED TOMOGRAPHY. Prof. Yasser Mostafa Kadah
MEDICAL EQUIPMENT: COMPUTED TOMOGRAPHY Prof. Yasser Mostafa Kadah www.k-space.org Recommended Textbook X-Ray Computed Tomography in Biomedical Engineering, by Robert Cierniak, Springer, 211 Computed Tomography
More informationCLASS HOURS: 4 CREDIT HOURS: 4 LABORATORY HOURS: 0
Revised 10/10 COURSE SYLLABUS TM 220 COMPUTED TOMOGRAPHY PHYSICS CLASS HOURS: 4 CREDIT HOURS: 4 LABORATORY HOURS: 0 CATALOG COURSE DESCRIPTION: This course is one of a three course set in whole body Computed
More informationMetal Artifact Reduction CT Techniques. Tobias Dietrich University Hospital Balgrist University of Zurich Switzerland
Metal Artifact Reduction CT Techniques R S S S Tobias Dietrich University Hospital Balgrist University of Zurich Switzerland N. 1 v o 4 1 0 2. Postoperative CT Metal Implants CT is accurate for assessment
More informationFinancial disclosure. Onboard imaging modality for IGRT
Tetrahedron Beam Computed Tomography Based On Multi-Pixel X- Ray Source and Its Application in Image Guided Radiotherapy Tiezhi Zhang, Ph.D. Advanced X-ray imaging Lab Financial disclosure Patent royalty
More information8/2/2016. Measures the degradation/distortion of the acquired image (relative to an ideal image) using a quantitative figure-of-merit
Ke Li Assistant Professor Department of Medical Physics and Department of Radiology School of Medicine and Public Health, University of Wisconsin-Madison This work is partially supported by an NIH Grant
More informationCT Systems and their standards
CT Systems and their standards Stephen Brown Engineering Measurement 11 th April 2012 Industrial X-ray computed tomography: The future of co-ordinate metrology? Burleigh Court, Loughborough University
More informationArtifact Mitigation in High Energy CT via Monte Carlo Simulation
PIERS ONLINE, VOL. 7, NO. 8, 11 791 Artifact Mitigation in High Energy CT via Monte Carlo Simulation Xuemin Jin and Robert Y. Levine Spectral Sciences, Inc., USA Abstract The high energy (< 15 MeV) incident
More informationBiomedical Imaging. Computed Tomography. Patrícia Figueiredo IST
Biomedical Imaging Computed Tomography Patrícia Figueiredo IST 2013-2014 Overview Basic principles X ray attenuation projection Slice selection and line projections Projection reconstruction Instrumentation
More informationC a t p h a n / T h e P h a n t o m L a b o r a t o r y
C a t p h a n 5 0 0 / 6 0 0 T h e P h a n t o m L a b o r a t o r y C a t p h a n 5 0 0 / 6 0 0 Internationally recognized for measuring the maximum obtainable performance of axial, spiral and multi-slice
More informationIterative and analytical reconstruction algorithms for varying-focal-length cone-beam
Home Search Collections Journals About Contact us My IOPscience Iterative and analytical reconstruction algorithms for varying-focal-length cone-beam projections This content has been downloaded from IOPscience.
More informationCh. 4 Physical Principles of CT
Ch. 4 Physical Principles of CT CLRS 408: Intro to CT Department of Radiation Sciences Review: Why CT? Solution for radiography/tomography limitations Superimposition of structures Distinguishing between
More informationUSING cone-beam geometry with pinhole collimation,
IEEE TRANSACTIONS ON NUCLEAR SCIENCE, VOL. 56, NO. 3, JUNE 2009 687 A Backprojection-Based Parameter Estimation Technique for Skew-Slit Collimation Jacob A. Piatt, Student Member, IEEE, and Gengsheng L.
More informationMulti-slice CT Image Reconstruction Jiang Hsieh, Ph.D.
Multi-slice CT Image Reconstruction Jiang Hsieh, Ph.D. Applied Science Laboratory, GE Healthcare Technologies 1 Image Generation Reconstruction of images from projections. textbook reconstruction advanced
More information8/7/2017. Disclosures. MECT Systems Overview and Quantitative Opportunities. Overview. Computed Tomography (CT) CT Numbers. Polyenergetic Acquisition
Quantitative Multi-Energy Computed Tomography: Imaging and Therapy Advancements Disclosures MECT Systems Overview and Quantitative Opportunities The speaker receives research funding from GE Healthcare
More informationNon-Stationary CT Image Noise Spectrum Analysis
Non-Stationary CT Image Noise Spectrum Analysis Michael Balda, Björn J. Heismann,, Joachim Hornegger Pattern Recognition Lab, Friedrich-Alexander-Universität Erlangen Siemens Healthcare, Erlangen michael.balda@informatik.uni-erlangen.de
More informationDiscrete Estimation of Data Completeness for 3D Scan Trajectories with Detector Offset
Discrete Estimation of Data Completeness for 3D Scan Trajectories with Detector Offset Andreas Maier 1, Patrick Kugler 2, Günter Lauritsch 2, Joachim Hornegger 1 1 Pattern Recognition Lab and SAOT Erlangen,
More informationAutomated Image Analysis Software for Quality Assurance of a Radiotherapy CT Simulator
Automated Image Analysis Software for Quality Assurance of a Radiotherapy CT Simulator Andrew J Reilly Imaging Physicist Oncology Physics Edinburgh Cancer Centre Western General Hospital EDINBURGH EH4
More informationSpectral analysis of non-stationary CT noise
Spectral analysis of non-stationary CT noise Kenneth M. Hanson Los Alamos Scientific Laboratory Int. Symposium and Course on Computed Tomography, Las Vegas, April 7-11, 1980 This presentation available
More informationJoint ICTP-TWAS Workshop on Portable X-ray Analytical Instruments for Cultural Heritage. 29 April - 3 May, 2013
2455-5 Joint ICTP-TWAS Workshop on Portable X-ray Analytical Instruments for Cultural Heritage 29 April - 3 May, 2013 Lecture NoteBasic principles of X-ray Computed Tomography Diego Dreossi Elettra, Trieste
More informationSuitability of a new alignment correction method for industrial CT
Suitability of a new alignment correction method for industrial CT Matthias Elter 1, Nicole Maass 1, Peter Koch 2 1 Siemens AG, Healthcare Sector, Erlangen, Germany, e-mail: matthias.elter@siemens.com,
More informationAdvanced Image Reconstruction Methods for Photoacoustic Tomography
Advanced Image Reconstruction Methods for Photoacoustic Tomography Mark A. Anastasio, Kun Wang, and Robert Schoonover Department of Biomedical Engineering Washington University in St. Louis 1 Outline Photoacoustic/thermoacoustic
More informationHIGH-SPEED THEE-DIMENSIONAL TOMOGRAPHIC IMAGING OF FRAGMENTS AND PRECISE STATISTICS FROM AN AUTOMATED ANALYSIS
23 RD INTERNATIONAL SYMPOSIUM ON BALLISTICS TARRAGONA, SPAIN 16-20 APRIL 2007 HIGH-SPEED THEE-DIMENSIONAL TOMOGRAPHIC IMAGING OF FRAGMENTS AND PRECISE STATISTICS FROM AN AUTOMATED ANALYSIS P. Helberg 1,
More informationDetermination of Three-Dimensional Voxel Sensitivity for Two- and Three-Headed Coincidence Imaging
IEEE TRANSACTIONS ON NUCLEAR SCIENCE, VOL. 50, NO. 3, JUNE 2003 405 Determination of Three-Dimensional Voxel Sensitivity for Two- and Three-Headed Coincidence Imaging Edward J. Soares, Kevin W. Germino,
More informationDEVELOPMENT OF CONE BEAM TOMOGRAPHIC RECONSTRUCTION SOFTWARE MODULE
Rajesh et al. : Proceedings of the National Seminar & Exhibition on Non-Destructive Evaluation DEVELOPMENT OF CONE BEAM TOMOGRAPHIC RECONSTRUCTION SOFTWARE MODULE Rajesh V Acharya, Umesh Kumar, Gursharan
More informationA prototype table-top inverse-geometry volumetric CT system
A prototype table-top inverse-geometry volumetric CT system Taly Gilat Schmidt a Department of Radiology, Stanford University, Stanford, California 94305 Josh Star-Lack NexRay, Inc., Los Gatos, California
More informationMetal Streak Artifacts in X-ray Computed Tomography: A Simulation Study
Metal Streak Artifacts in X-ray Computed Tomography: A Simulation Study B. De Man, J. Nuyts, P. Dupont, G. Marchal and P. Suetens Medical Image Computing, ESAT-PSI, K.U.Leuven, B-3000 Leuven, Belgium Department
More informationRADIOLOGY AND DIAGNOSTIC IMAGING
Day 2 part 2 RADIOLOGY AND DIAGNOSTIC IMAGING Dr hab. Zbigniew Serafin, MD, PhD serafin@cm.umk.pl 2 3 4 5 CT technique CT technique 6 CT system Kanal K: RSNA/AAPM web module: CT Systems & CT Image Quality
More informationComputational Medical Imaging Analysis Chapter 4: Image Visualization
Computational Medical Imaging Analysis Chapter 4: Image Visualization Jun Zhang Laboratory for Computational Medical Imaging & Data Analysis Department of Computer Science University of Kentucky Lexington,
More information1. Deployment of a framework for drawing a correspondence between simple figure of merits (FOM) and quantitative imaging performance in CT.
Progress report: Development of assessment and predictive metrics for quantitative imaging in chest CT Subaward No: HHSN6801000050C (4a) PI: Ehsan Samei Reporting Period: month 1-18 Deliverables: 1. Deployment
More informationMicro-CT Methodology Hasan Alsaid, PhD
Micro-CT Methodology Hasan Alsaid, PhD Preclinical & Translational Imaging LAS, PTS, GlaxoSmithKline 20 April 2015 Provide basic understanding of technical aspects of the micro-ct Statement: All procedures
More informationEnhanced material contrast by dual-energy microct imaging
Enhanced material contrast by dual-energy microct imaging Method note Page 1 of 12 2 Method note: Dual-energy microct analysis 1. Introduction 1.1. The basis for dual energy imaging Micro-computed tomography
More informationValidation of GEANT4 for Accurate Modeling of 111 In SPECT Acquisition
Validation of GEANT4 for Accurate Modeling of 111 In SPECT Acquisition Bernd Schweizer, Andreas Goedicke Philips Technology Research Laboratories, Aachen, Germany bernd.schweizer@philips.com Abstract.
More informationFeldkamp-type image reconstruction from equiangular data
Journal of X-Ray Science and Technology 9 (2001) 113 120 113 IOS Press Feldkamp-type image reconstruction from equiangular data Ben Wang a, Hong Liu b, Shiying Zhao c and Ge Wang d a Department of Elec.
More informationA new calibration-free beam hardening reduction method for industrial CT
A new calibration-free beam hardening reduction method for industrial CT ECC 2 for industrial CT Tobias Würfl 1, Nicole Maaß 2, Frank Dennerlein 2, Andreas K. Maier 1 1 Pattern Recognition Lab, FAU Erlangen-Nürnberg;
More informationSpatial Resolution Properties in Penalized-Likelihood Reconstruction of Blurred Tomographic Data
Spatial Resolution Properties in Penalized-Likelihood Reconstruction of Blurred Tomographic Data Wenying Wang, Grace J. Gang and J. Webster Stayman Department of Biomedical Engineering, Johns Hopkins University,
More informationThe Near Future in Cardiac CT Image Reconstruction
SCCT 2010 The Near Future in Cardiac CT Image Reconstruction Marc Kachelrieß Institute of Medical Physics (IMP) Friedrich-Alexander Alexander-University Erlangen-Nürnberg rnberg www.imp.uni-erlangen.de
More informationML reconstruction for CT
ML reconstruction for CT derivation of MLTR rigid motion correction resolution modeling polychromatic ML model dual energy ML model Bruno De Man, Katrien Van Slambrouck, Maarten Depypere, Frederik Maes,
More informationA Radiometry Tolerant Method for Direct 3D/2D Registration of Computed Tomography Data to X-ray Images
A Radiometry Tolerant Method for Direct 3D/2D Registration of Computed Tomography Data to X-ray Images Transfer Function Independent Registration Boris Peter Selby 1, Georgios Sakas 2, Stefan Walter 1,
More informationCorso di laurea in Fisica A.A Fisica Medica 4 TC
Corso di laurea in Fisica A.A. 2007-2008 Fisica Medica 4 TC Computed Tomography Principles 1. Projection measurement 2. Scanner systems 3. Scanning modes Basic Tomographic Principle The internal structure
More informationmicroct Systems for Life Science Innovation with Integrity High Resolution Microtomography for in vivo and ex vivo Applications Microtomography
microct Systems for Life Science High Resolution Microtomography for in vivo and ex vivo Applications Innovation with Integrity Microtomography SkyScan 1278 High Throughput Large Field of View in vivo
More information3/27/2012 WHY SPECT / CT? SPECT / CT Basic Principles. Advantages of SPECT. Advantages of CT. Dr John C. Dickson, Principal Physicist UCLH
3/27/212 Advantages of SPECT SPECT / CT Basic Principles Dr John C. Dickson, Principal Physicist UCLH Institute of Nuclear Medicine, University College London Hospitals and University College London john.dickson@uclh.nhs.uk
More informationAIDR 3D Iterative Reconstruction:
Iterative Reconstruction: Integrated, Automated and Adaptive Dose Reduction Erin Angel, PhD Manager, Clinical Sciences, CT Canon Medical Systems USA Iterative Reconstruction 1 Since the introduction of
More informationA framework of modeling detector systems for computed tomography simulations
Home Search Collections Journals About Contact us My IOPscience A framework of modeling detector systems for computed tomography simulations This content has been downloaded from IOPscience. Please scroll
More informationDUAL energy CT (DECT) is a modality where one and. Empirical Dual Energy Calibration (EDEC) for Cone-Beam Computed Tomography
Empirical Dual Energy Calibration (EDEC) for Cone-Beam Computed Tomography Marc Kachelrieß, Member, IEEE, Timo Berkus, Philip Stenner, Willi A. Kalender Abstract Material selective imaging using dual energy
More informationDesign and performance characteristics of a Cone Beam CT system for Leksell Gamma Knife Icon
Design and performance characteristics of a Cone Beam CT system for Leksell Gamma Knife Icon WHITE PAPER Introduction Introducing an image guidance system based on Cone Beam CT (CBCT) and a mask immobilization
More informationMEDICAL IMAGING 2nd Part Computed Tomography
MEDICAL IMAGING 2nd Part Computed Tomography Introduction 2 In the last 30 years X-ray Computed Tomography development produced a great change in the role of diagnostic imaging in medicine. In convetional
More informationSPECT QA and QC. Bruce McBride St. Vincent s Hospital Sydney.
SPECT QA and QC Bruce McBride St. Vincent s Hospital Sydney. SPECT QA and QC What is needed? Why? How often? Who says? QA and QC in Nuclear Medicine QA - collective term for all the efforts made to produce
More informationImprovement of Efficiency and Flexibility in Multi-slice Helical CT
J. Shanghai Jiaotong Univ. (Sci.), 2008, 13(4): 408 412 DOI: 10.1007/s12204-008-0408-x Improvement of Efficiency and Flexibility in Multi-slice Helical CT SUN Wen-wu 1 ( ), CHEN Si-ping 2 ( ), ZHUANG Tian-ge
More informationEvaluation of Spectrum Mismatching using Spectrum Binning Approach for Statistical Polychromatic Reconstruction in CT
Evaluation of Spectrum Mismatching using Spectrum Binning Approach for Statistical Polychromatic Reconstruction in CT Qiao Yang 1,4, Meng Wu 2, Andreas Maier 1,3,4, Joachim Hornegger 1,3,4, Rebecca Fahrig
More informationMedical Imaging BMEN Spring 2016
Name Medical Imaging BMEN 420-501 Spring 2016 Homework #4 and Nuclear Medicine Notes All questions are from the introductory Powerpoint (based on Chapter 7) and text Medical Imaging Signals and Systems,
More informationIntroduction to Biomedical Imaging
Alejandro Frangi, PhD Computational Imaging Lab Department of Information & Communication Technology Pompeu Fabra University www.cilab.upf.edu X-ray Projection Imaging Computed Tomography Digital X-ray
More informationImplementation and evaluation of a fully 3D OS-MLEM reconstruction algorithm accounting for the PSF of the PET imaging system
Implementation and evaluation of a fully 3D OS-MLEM reconstruction algorithm accounting for the PSF of the PET imaging system 3 rd October 2008 11 th Topical Seminar on Innovative Particle and Radiation
More informationDigital Volume Correlation for Materials Characterization
19 th World Conference on Non-Destructive Testing 2016 Digital Volume Correlation for Materials Characterization Enrico QUINTANA, Phillip REU, Edward JIMENEZ, Kyle THOMPSON, Sharlotte KRAMER Sandia National
More informationTomoTherapy Related Projects. An image guidance alternative on Tomo Low dose MVCT reconstruction Patient Quality Assurance using Sinogram
TomoTherapy Related Projects An image guidance alternative on Tomo Low dose MVCT reconstruction Patient Quality Assurance using Sinogram Development of A Novel Image Guidance Alternative for Patient Localization
More informationMedical Image Reconstruction Term II 2012 Topic 6: Tomography
Medical Image Reconstruction Term II 2012 Topic 6: Tomography Professor Yasser Mostafa Kadah Tomography The Greek word tomos means a section, a slice, or a cut. Tomography is the process of imaging a cross
More informationHelical 4D CT pitch management for the Brilliance CT Big Bore in clinical practice
JOURNAL OF APPLIED CLINICAL MEDICAL PHYSICS, VOLUME 16, NUMBER 3, 2015 Helical 4D CT pitch management for the Brilliance CT Big Bore in clinical practice Guido Hilgers, a Tonnis Nuver, André Minken Department
More informationReconstruction in CT and relation to other imaging modalities
Reconstruction in CT and relation to other imaging modalities Jørgen Arendt Jensen November 1, 2017 Center for Fast Ultrasound Imaging, Build 349 Department of Electrical Engineering Center for Fast Ultrasound
More informationA study on image quality provided by a kilovoltage cone-beam computed tomography
JOURNAL OF APPLIED CLINICAL MEDICAL PHYSICS, VOLUME 14, NUMBER 1, 2013 A study on image quality provided by a kilovoltage cone-beam computed tomography Julia Garayoa a and Pablo Castro Servicio de Radiofísica,
More informationSlide 1. Technical Aspects of Quality Control in Magnetic Resonance Imaging. Slide 2. Annual Compliance Testing. of MRI Systems.
Slide 1 Technical Aspects of Quality Control in Magnetic Resonance Imaging Slide 2 Compliance Testing of MRI Systems, Ph.D. Department of Radiology Henry Ford Hospital, Detroit, MI Slide 3 Compliance Testing
More informationRefinement of Imaging Processing of Scatter Correction and Beam Hardening Tools for Industrial Radiography and Cone Beam CT
Digital Industrial Radiology and Computed Tomography (DIR 2015) 22-25 June 2015, Belgium, Ghent - www.ndt.net/app.dir2015 More Info at Open Access Database www.ndt.net/?id=18073 Refinement of Imaging Processing
More informationRadiology. Marta Anguiano Millán. Departamento de Física Atómica, Molecular y Nuclear Facultad de Ciencias. Universidad de Granada
Departamento de Física Atómica, Molecular y Nuclear Facultad de Ciencias. Universidad de Granada Overview Introduction Overview Introduction Tecniques of imaging in Overview Introduction Tecniques of imaging
More informationNoise power spectrum and modulation transfer function analysis of breast tomosynthesis imaging
Noise power spectrum and modulation transfer function analysis of breast tomosynthesis imaging Weihua Zhou a, Linlin Cong b, Xin Qian c, Yueh Z. Lee d, Jianping Lu c,e, Otto Zhou c,e, *Ying Chen a,b a
More informationHow beam hardening influences the dimensional geometry in X-ray computed tomography
How beam hardening influences the dimensional geometry in X-ray computed tomography More info about this article: http://www.ndt.net/?id=20809 Hannah Corcoran 1, 2, Stephen Brown 2, Stuart Robson 1, Robert
More informationDeviceless respiratory motion correction in PET imaging exploring the potential of novel data driven strategies
g Deviceless respiratory motion correction in PET imaging exploring the potential of novel data driven strategies Presented by Adam Kesner, Ph.D., DABR Assistant Professor, Division of Radiological Sciences,
More informationBasics of treatment planning II
Basics of treatment planning II Sastry Vedam PhD DABR Introduction to Medical Physics III: Therapy Spring 2015 Dose calculation algorithms! Correction based! Model based 1 Dose calculation algorithms!
More informationThe theory and practical aspects of proton imaging proton radiography (prad) and proton tomography (pct)
The theory and practical aspects of proton imaging proton radiography (prad) and proton tomography (pct) Fritz DeJongh, ProtonVDA Inc August 30 2018 Stay away from negative people. They have a problem
More informationApplying Hounsfield unit density calibration in SkyScan CT-analyser
1 Bruker-microCT Method note Applying Hounsfield unit density calibration in SkyScan CT-analyser Hounsfield units (HU) are a standard unit of x-ray CT density, in which air and water are ascribed values
More informationCT Reconstruction with Good-Orientation and Layer Separation for Multilayer Objects
17th World Conference on Nondestructive Testing, 25-28 Oct 2008, Shanghai, China CT Reconstruction with Good-Orientation and Layer Separation for Multilayer Objects Tong LIU 1, Brian Stephan WONG 2, Tai
More information8/1/2017. Current Technology: Energy Integrating Detectors. Principles, Pitfalls and Progress in Photon-Counting-Detector Technology.
Photon Counting Detectors and Their Applications in Medical Imaging Principles, Pitfalls and Progress in Photon-Counting-Detector Technology Taly Gilat Schmidt, PhD Associate Professor Department of Biomedical
More informationTotal Variation Regularization Method for 3D Rotational Coronary Angiography
Total Variation Regularization Method for 3D Rotational Coronary Angiography Haibo Wu 1,2, Christopher Rohkohl 1,3, Joachim Hornegger 1,2 1 Pattern Recognition Lab (LME), Department of Computer Science,
More informationJames R Halama, PhD Loyola University Medical Center
James R Halama, PhD Loyola University Medical Center Conflicts of Interest Nuclear Medicine and PET physics reviewer for the ACR Accreditation program Learning Objectives Be familiar with the tests recommended
More informationMathematical methods and simulations tools useful in medical radiation physics
Mathematical methods and simulations tools useful in medical radiation physics Michael Ljungberg, professor Department of Medical Radiation Physics Lund University SE-221 85 Lund, Sweden Major topic 1:
More informationConflicts of Interest Nuclear Medicine and PET physics reviewer for the ACR Accreditation program
James R Halama, PhD Loyola University Medical Center Conflicts of Interest Nuclear Medicine and PET physics reviewer for the ACR Accreditation program Learning Objectives 1. Be familiar with recommendations
More informationHIGH RESOLUTION COMPUTED TOMOGRAPHY FOR METROLOGY
HIGH RESOLUTION COMPUTED TOMOGRAPHY FOR METROLOGY David K. Lehmann 1, Kathleen Brockdorf 1 and Dirk Neuber 2 1 phoenix x-ray Systems + Services Inc. St. Petersburg, FL, USA 2 phoenix x-ray Systems + Services
More informationEnhancement Image Quality of CT Using Single Slice Spiral Technique
Enhancement Image Quality of CT Using Single Slice Spiral Technique Doaa. N. Al Sheack 1 and Dr.Mohammed H. Ali Al Hayani 2 1 2 Electronic and Communications Engineering Department College of Engineering,
More informationCT Basics Principles of Spiral CT Dose. Always Thinking Ahead.
1 CT Basics Principles of Spiral CT Dose 2 Who invented CT? 1963 - Alan Cormack developed a mathematical method of reconstructing images from x-ray projections Sir Godfrey Hounsfield worked for the Central
More informationCT vs. VolumeScope: image quality and dose comparison
CT vs. VolumeScope: image quality and dose comparison V.N. Vasiliev *a, A.F. Gamaliy **b, M.Yu. Zaytsev b, K.V. Zaytseva ***b a Russian Sci. Center of Roentgenology & Radiology, 86, Profsoyuznaya, Moscow,
More informationApplication of 450 kv Computed Tomography to Engine Blocks with Steel Liners
Application of 450 kv Computed Tomography to Engine Blocks with Steel Liners Charles R. Smith, Kevin Holt BIR, Inc. Uwe Bischoff, Bernd Georgi, Ferdinand Hansen, Frank Jeltsch Volkswagen Commercial Vehicles
More informationMulti-spectral (W, Mo, Cu, and Ag) XCT measurements
Multi-spectral (W, Mo, Cu, and Ag) XCT measurements Marko Katić 1, Damir Markučič 1, Gorana Baršić 1 Faculty of mechanical engineering and naval architecture, Ivana Lucica 5, Zagreb, Croatia, marko.katic@fsb.hr
More informationSINGLE-PHOTON emission computed tomography
1458 IEEE TRANSACTIONS ON NUCLEAR SCIENCE, VOL. 59, NO. 4, AUGUST 2012 SPECT Imaging With Resolution Recovery Andrei V. Bronnikov Abstract Single-photon emission computed tomography (SPECT) is a method
More informationOptimization of scanner parameters for dual energy micro-ct
Optimization of scanner parameters for dual energy micro-ct E. PAUWELS* 1, J. DHAENE 1, A. DE MUYNCK 1 E., M. DIERICK 1, L. VAN HOOREBEKE 1 1 UGCT Dept. Physics and Astronomy, Ghent University, Proeftuinstraat
More information