DOCSLIB.ORG

PET Imaging: an Overview and Instrumentation

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
PET Imaging: an Overview and Instrumentation CONTINUING EDUCATION PET Imaging: An Overview and Instrumentation Farhad Daghighian, Ronald Sumida, and Michael E. Phelps Division ofNuclear Medicine and Biophysics, Department ofRadiological Sciences; and Laboratory ofNuclear Medicine, Laboratories of Biomedical and Environmental Sciences (DOE)*, UCLA School ofMedicine, Los Angeles, California gen in many chemical compounds. None of the above This is the first article of a four-part series on positron elements have any isotope which emits a gamma ray emission tomography (PET). Upon completing the article, the suitable for imaging with a gamma camera. Hence, one reader should be able to: (1) comprehend the basic principles of the advantages of PET over SPECT is that it deals ofPET; (2) explain various technical aspects; and ( 3) identify with isotopes of those elements that are the building radiopharmaceuticals used in PET imaging. blocks of biomolecules. BRIEF HISTORY Positron emission tomography (PET) is a rapidly growing AND FUTURE OUTLOOK OF PET technique within nuclear medicine. A radiopharmaceutical Positron imaging began with the two-dimensional sodium labeled with a positron emitting isotope is administered intra­ iodide detector-based scanning devices developed in the late venously or by inhalation to the patient, and the PET scanner 1950s and 1960s by Wrenn et al. ( 4) and Brownell et al. (5). images the distribution of that radiopharmaceutical. It is the Burham and Brownell also developed a dual-headed multi­ only imaging modality capable of providing quantitative in­ detector camera that provided a limited form of"focal plane" formation about biochemical and physiologic processes (J- tomography ( 6). Robertson and Niel took a different ap­ 3). Other techniques like magnetic resonance imaging (MRI) proach and used a "blurring tomography" with a circular and x-ray computerized tomography (CT) generally image array of sodium iodide detectors ( 7). This latter approach was the anatomy or the structure of the body. the positron version of the device Kuhl and Edwards devel­ Positron emission tomography imaging has some unique oped for single-photon emitting radioisotopes (8). features, which can be summarized as follows: A turning point in medical imaging was reached when 1. The effect of gamma ray attenuation in tissue is removed Hounsfield and Cormack developed x-ray computed tomog­ from the PET image in an exact way, thereby making raphy, for which they shared the Nobel prize in 1978. Earlier the image an accurate measurement of the local radio­ positron imaging devices did not employ the principle of isotope concentration (J-3). computed tomography. 2. There are no collimators in front of the PET detectors; The first true positron computed tomography device was therefore the efficiency of PET is much higher than that developed in 1974 by Phelps, Hoffman, Ter-Pogosian and of single-photon emission computed tomography colleagues ( 9). This work was the beginning of a rapid advance (SPECT). (In the gamma camera more than 99% of the in the principles and techniques of PET. For example, Brown­ emitted gamma rays are absorbed or scattered by the ell et al. (10) and Muehllehner et al. (1 1) developed rotating collimators.) multicrystal and dual-head Anger camera PET systems, re­ 3. Most of the organic chemicals found in the body are spectively. Cho et al. (12), Derenzo et al. (13), Bohm et al. made of carbon, oxygen, nitrogen, and hydrogen. The (14), Tanaka et al. (15), and others developed the early first three of these elements have isotopes which emit circular versions of PET scanners. Allemand et al. introduced positrons, "C (ty, = 20 min), 150 (t.;, = 2 min), and 13 N the first time-of-flight PET system ( 16). Many other academic (ty, = 10 min). Auorine-18 C8F) (t•;, = 109 min), a and comercially-based investigators subsequently contributed positron emitting isotope, can be substituted for hydro- to the development of PET. Research PET centers were established throughout North America, Europe, and Asia during the late 1970s and 1980s. This not only increased ·Operated for the U.S. Department of Energy by the University of California under contract #DE-ACOJ-76-SFOOO 12. biologic research with PET, but also increased research into For reprints contact: Farhad Daghighian PhD, Dept. of Medical Physics, developing new labeled compounds, tracer kinetic assay meth­ Memorial Sloan-Kettering Cancer Center, 1275 York Ave .• New York, NY 10021. ods, and improving PET scanners. The mid-1980s were the VOLUME 18, NUMBER 1, MARCH 1990 5 beginning of the growth in technology to miniaturize and TABLE 1. Examples of Clinical PET Procedures simplify cyclotrons specifically for PET. In addition, auto­ mated chemical synthesis techniques for simplifying the rou­ Procedure Clinical Use tine production of labeled compounds were initiated and 1 . Rest/Stress detection of coronary integrated into the cyclotron technology. artery disease. The principles of PET used to measure and image biologic 3 82 ' NH or Rb plus FOG* 1. Determination of cardiac tissue vi­ processes in the living human subject are sound and their 3 ability for selecting patients for re­ value undeniable. The use of PET to perform biochemical vascularization. examinations of patients for clinical management has now 2. Differentiation of iodiopathic from become the motivation to develop a continuing evolution of ischemic cardiomyopathies: Via­ solutions to the practicalities of its use. ble ischemic cardiomyopathies -+ revascularization; iodiopathic car­ diomyopathies -+ transplant. WHAT ARE THE CLINICAL USES OF PET? FOG 1. Detection, grading degree of ma­ Although PET has been a powerful research tool in medi­ lignancy, post-treatment determi­ cine, it has been shown to be a unique and critical diagnostic nation of reoccurrence and treat­ ment efficacy in tumors (cerebral modality for clinical use. This is because it provides unique and systemic). physiologic and biochemical information about the brain, 2. Differential diagnosis of Alz­ heart, and the rest of the body. The origin of disease is heimer's, multiple infarct demen­ fundamentally biochemical in nature. Therefore, to obtain tia and chronic depression. the most accurate diagnoses and most effective treatment, it 3. Localization of seizure focus in adult and pediatric epilepsy for is desirable to know the biochemical status of the organ or surgical resection. organ system in question. 4. Differential diagnosis of Hunting­ The most common uses of PET in clinical studies are ton's Disease. measurement of the metabolic rate of glucose in different 5. Characterization of cerebral dam­ locations of the brain and the heart. These studies can: age and function on cerebral palsy. I. Help the clinician to pinpoint the location of epileptic 1 . Characterization of hemodynamic foci in seizure disorder patients (3). and metabolic deficits, tissue via­ 2. Identify different forms of dementia and degenerative bility, and therapeutic efficacy in diseases (i.e., Alzheimer's, Parkinson's or Huntington's cerebral vascular diseases (e.g., diseases). stroke). 18 3. Identify the pathology of brain tumors and access the F-L-DOPA 1 . Detection of movement disorders viability of the brain tissue and evaluate the viability of and characterization of dopamine deficiencies. the myocardium in patients with cardiac disease (1 7- 1. Bone scans, detection and moni­ 20). toring of therapy in degenerative bone disease. Blood flow to different locations of the brain is quantitated 18 by PET using '50-labeled water (3), and in the heart by 13N­ • F-Iabeled fluorodeoxyglucose. labeled ammonia or 82Rb (20). Cerebral blood flow measure­ ments combined with measurement of the cerebral metabolic a full course of radiation therapy prior to these scans.) The rate of oxygen is an indicator of the physiologic time course, PET scan is performed 40 min after the injection of 18F­ and metabolic consequences of, and recovery from stroke (3). Iabeled fluorodeoxyglucose (FOG), which is an analog of Myocardial blood flow measurements combined with the glucose. The SPECT image is acquired after the injection of information about the glucose metabolic rate aids the clinician zo'Tl. in identifying whether the patient has viable myocardium, In the PET image, the concentration of FOG is high in the which would benefit from revascularization (20). Some ex­ outer layer of the tumor (the dark semicircle around the amples of PET clinical applications are summarized in Table tumor). This specifically indicates the presence of active tu­ I. There are, however, many others that are discussed in the mor cells since high grade tumor cells use more glucose (21). literature. The tissue at the center of the tumor is dead and, therefore, An example of how metabolic information acquired by does not metabolize glucose. In the CT scan, the bright ring PET is an aid to the clinician is shown in Figure I. The CT, around the tumor only suggests that the 888 is disrupted but PET, and SPECT scans of a patient with biopsy-proven high­ not whether there is an active tumor. The SPECT image grade brain tumor is presented. The CT scan, performed after shows an area of increased uptake of 201 Tl, yet provides little the injection of a contrast agent, indicates a disruption of the information about state of the tumor and the surrounding blood brain barrier (888) that can be caused by the tumor, tissues. The information acquired by PET in this case is radiation necroses or edema (3), the specifics of which can important in the future treatment of the patient. Many other not be differentiated by CT or MRI (3). (The patient received examples of how PET and its physiologic and metabolic 8 .JOURNAL OF NUCLEAR MEDICINE TECHNOLOGY nuclei in the surrounding medium (Fig. 2). Eventually, it will collide with one of the many electrons in the medium and spontaneous annihilation takes place: e• + e- --+Gamma + Gamma. All these events are so fast that for all practical purposes the emission and annihilation of the positron can be considered simultaneous.
Load more

Recommended publications
  • Design of Neutron and Gamma Ray Diagnostics for the Start-Up Phase of the DTT Tokamak
    46th EPS Conference on Plasma Physics P5.1105 Design of neutron and gamma ray diagnostics for the start-up phase of the DTT tokamak M. Angelone 1, D. Rigamonti 2, M Tardocchi 2, F. Causa 2, S. Fiore 1, L. C. Giacomelli 2, G. Gorini 3,2 , F. Moro 1, M. Nocente 3,2 , M. Osipenko 4, M. Pillon 1, , M. Ripani 4, R. Villari 1 1ENEA, Centro Ricerche Frascati, Frascati, Italy 2Istituto per la Scienza e Tecnologia dei Plasmi, CNR, Milan, Italy 3Dipart. di Fisica “G. Occhialini”, Università degli Studi di Milano-Bicocca, Milano, Italy 4Istituto Nazionale di Fisica Nucleare, Genova, Italy e-mail : [email protected] Abstract The Divertor Tokamak Test (DTT) facility, which is under design for construction in Frascati (Italy), will produce neutron yield up to 1.3*10 17 n/s at full power (H-mode scenario). This calls for an accurate design and selection of the 2.5 MeV neutron diagnostic systems and detectors which can give the comprehensive exploitation of the high neutron fluxes. Measurements of 14 MeV neutrons (which are about 1% of the total neutron yield) coming from the triton burn-up will also be performed. DTT will reach its best performances after a preliminary phase , needed to assess and improve the machine parameters. Here we present the neutron and gamma-ray diagnostics systems which are under design for the initial start-up phase of DTT. The design work benefits from the experience gathered by the community on high power tokamak such as JET. These systems, also called day-1 diagnostics, are: i) Neutron flux monitors which measure the 2.5 and 14 MeV neutron yield s, ii) Neutron/Gamma camera for the reconstruction of the neutron and gamma ray emission profile of the plasma , iii) Hard x-ray monitors for measurements of the bremsstrahlung radiation produced by runway electrons in the 1-40 MeV energy range 1.0 Introduction The Divertor Tokamak Test (DTT) facility, which is under design for construction in Frascati (Italy), will produce neutron yield up to 1.3*10 17 n/s at full power (H-mode scenario).
    [Show full text]
  • MRC Review of Positron Emission Tomography (PET) Within the Medical Imaging Research Landscape
    MRC Review of Positron Emission Tomography (PET) within The Medical Imaging Research Landscape August 2017 Content 1 Introduction 3 2 The medical imaging research landscape in the UK 4 2.1 Magnetic resonance imaging (MRI) 4 2.2 PET, including PET-MRI 6 2.3 Magnetoencephalography 7 3 Scientific uses and demand for PET imaging 8 3.1 Clinical practice 8 3.2 Research use of PET 8 3.3 Demand for PET 10 4 Bottlenecks 11 4.1 Cost 11 4.2 Radiochemistry requirements 12 4.3 Capacity 13 4.4 Analysis and modelling 13 5 Future Opportunities 14 5.1 Mitigating the high costs 14 5.2 Capacity building 14 5.3 Better Networking 15 6 Discussion and conclusions 16 Appendix 1 Experts consulted in the review 17 Appendix 2 Interests of other funders 18 Appendix 3 Usage and cost of PET in research 21 Appendix 4 Summary of facilities and capabilities across UK PET centres of excellence 23 2 1. Introduction This report aims to provide a review of Positron Emission Tomography (PET) within the medical imaging research landscape and a high level strategic review of the UK’s capabilities and needs in this area. The review was conducted by face-to-face and telephone interviews with 35 stakeholders from UK centres of excellence, international experts, industry and other funders (list at appendix 1). Data were also collected on facilities, resources and numbers of scans conducted across the centres of excellence using a questionnaire. The review has focused predominantly on PET imaging, but given MRC’s significant recent investment in other imaging modalities (7T Magnetic Resonance Imaging (MRI), hyperpolarised MRI) through the Clinical Research Infrastructure (CRI) Initiative, these are also considered more briefly.
    [Show full text]
  • Investigational New Drug Applications for Positron Emission Tomography (PET) Drugs
    Guidance Investigational New Drug Applications for Positron Emission Tomography (PET) Drugs GUIDANCE U.S. Department of Health and Human Services Food and Drug Administration Center for Drug Evaluation and Research (CDER) December 2012 Clinical/Medical Guidance Investigational New Drug Applications for Positron Emission Tomography (PET) Drugs Additional copies are available from: Office of Communications Division of Drug Information, WO51, Room 2201 Center for Drug Evaluation and Research Food and Drug Administration 10903 New Hampshire Ave. Silver Spring, MD 20993-0002 Phone: 301-796-3400; Fax: 301-847-8714 [email protected] http://www.fda.gov/Drugs/GuidanceComplianceRegulatoryInformation/Guidances/default.htm U.S. Department of Health and Human Services Food and Drug Administration Center for Drug Evaluation and Research (CDER) December 2012 Clinical/Medical Contains Nonbinding Recommendations TABLE OF CONTENTS I. INTRODUCTION..............................................................................................................................................1 II. BACKGROUND ................................................................................................................................................1 A. PET DRUGS .....................................................................................................................................................1 B. IND..................................................................................................................................................................2
    [Show full text]
  • Chapter 3 the Fundamentals of Nuclear Physics Outline Natural
    Outline Chapter 3 The Fundamentals of Nuclear • Terms: activity, half life, average life • Nuclear disintegration schemes Physics • Parent-daughter relationships Radiation Dosimetry I • Activation of isotopes Text: H.E Johns and J.R. Cunningham, The physics of radiology, 4th ed. http://www.utoledo.edu/med/depts/radther Natural radioactivity Activity • Activity – number of disintegrations per unit time; • Particles inside a nucleus are in constant motion; directly proportional to the number of atoms can escape if acquire enough energy present • Most lighter atoms with Z<82 (lead) have at least N Average one stable isotope t / ta A N N0e lifetime • All atoms with Z > 82 are radioactive and t disintegrate until a stable isotope is formed ta= 1.44 th • Artificial radioactivity: nucleus can be made A N e0.693t / th A 2t / th unstable upon bombardment with neutrons, high 0 0 Half-life energy protons, etc. • Units: Bq = 1/s, Ci=3.7x 1010 Bq Activity Activity Emitted radiation 1 Example 1 Example 1A • A prostate implant has a half-life of 17 days. • A prostate implant has a half-life of 17 days. If the What percent of the dose is delivered in the first initial dose rate is 10cGy/h, what is the total dose day? N N delivered? t /th t 2 or e Dtotal D0tavg N0 N0 A. 0.5 A. 9 0.693t 0.693t B. 2 t /th 1/17 t 2 2 0.96 B. 29 D D e th dt D h e th C. 4 total 0 0 0.693 0.693t /th 0.6931/17 C.
    [Show full text]
  • Radiation Quick Reference Guide Recommend Contacting Your State Fusion Center
    Domestic Nuclear Detection Office If you encounter something suspicious follow your specific local protocols. Radiation Quick Reference Guide Recommend contacting your state fusion center. DNDO is available 24/7 to assist at 1-877-DNDO-JAC / 1-877-363-6522 JAC Information Line 202-254-7179 Email: [email protected] Nuclear Concerns/ Threats 1. Nuclear Weapon - a device that releases nuclear energy in an ex- Isotopes of Concern for use in RDDs - with common uses plosive manner. Uses Highly Enriched Uranium (HEU) and/or 1. Cobalt-60 – cancer treatment, level/ Plutonium. density gauge, teletherapy, radiography, 2. Improvised Nuclear Device (IND) - a nuclear weapon fabricated food sterilization/irradiation, by a terrorist organization or rogue nation. brachytherapy 2. Iridium-192 – Radiography/non- destructive testing, flaw detection, brachy- therapy “cancer seed”, skin cancer Cobalt 60 sources Uranium “superficial” brachytherapy Plutonium 3. Uranium a. Uranium exists naturally in the earth’s crust. Of the different “isotopes” of uranium, U-235 is the one required to produce a Iridium sentinel and nuclear weapon. gamma camera b. Natural uranium contains a small amount of U-235 (<1%) which Cesium Seeds must be separated in complex extraction processes to create HEU. The predominant uranium isotope is U-238. 3. Cesium-137 - Gauge/level gauge, industrial radiography, brachyther- c. Highly Enriched Uranium (HEU) refers to uranium usable in weap- apy/teletherapy, well logging/density gauges ons due to its enrichment in U-235. 4. Strontium-90 – Radioisotope thermoelectric generator (RTG), fis- d. Approximately 25 kg of HEU is required for a nuclear weapon. sion product, industrial gauges, medical treatment e.
    [Show full text]
  • A New Gamma Camera for Positron Emission Tomography
    INIS-mf—11552 A new gamma camera for Positron Emission Tomography NL89C0813 P. SCHOTANUS A new gamma camera for Positron Emission Tomography A new gamma camera for Positron Emission Tomography PROEFSCHRIFT TER VERKRIJGING VAN DE GRAAD VAN DOCTOR AAN DE TECHNISCHE UNIVERSITEIT DELFT, OP GEZAG VAN DE RECTOR MAGNIFICUS, PROF.DRS. P.A. SCHENCK, IN HET OPENBAAR TE VERDEDIGEN TEN OVERSTAAN VAN EEN COMMISSIE, AANGEWEZEN DOOR HET COLLEGE VAN DECANEN, OP DINSDAG 20 SEPTEMBER 1988TE 16.00 UUR. DOOR PAUL SCHOTANUS '$ DOCTORANDUS IN DE NATUURKUNDE GEBOREN TE EINDHOVEN Dit proefschrift is goedgekeurd door de promotor Prof.dr. A.H. Wapstra s ••I Sommige boeken schijnen geschreven te zijn.niet opdat men er iets uit zou leren, maar opdat men weten zal, dat de schrijver iets geweten heeft. Goethe Contents page 1 Introduction 1 2 Nuclear diagnostics as a tool in medical science; principles and applications 2.1 The position of nuclear diagnostics in medical science 2 2.2 The detection of radiation in nuclear diagnostics: 5 standard techniques 2.3 Positron emission tomography 7 2.4 Positron emitting isotopes 9 2.5 Examples of radiodiagnostic studies with PET 11 2.6 Comparison of PET with other diagnostic techniques 12 3 Detectors for positron emission tomography 3.1 The absorption d 5H keV annihilation radiation in solids 15 3.2 Scintillators for the detection of annihilation radiation 21 3.3 The detection of scintillation light 23 3.4 Alternative ways to detect annihilation radiation 28 3-5 Determination of the point of annihilation: detector geometry,
    [Show full text]
  • Gamma Cameras
    OECD Health Statistics 2021 Definitions, Sources and Methods Gamma cameras Number of Gamma cameras. A Gamma camera (including Single Photon Emission Computed Tomography, SPECT) is used for a nuclear medicine procedure in which the camera rotates around the patient to register gamma rays emission from an isotope injected to the patient's body. The gathered data are processed by a computer to form a tomographic (cross-sectional) image. Inclusion - SPECT-CT systems using image fusion (superposition of SPECT and CT images). Sources and Methods Australia Source of data: Department of Health. Unpublished data from Location Specific Position Number register. Reference period: Years reported are financial years 1st July to 31st June (e.g. data for 2012 are as at 30th June 2012). Coverage: Data from 2008 onwards represent the number of units approved for billing to Medicare only. Units may be removed from one location and re-registered in another location. Austria Source of data: Austrian Federal Ministry of Social Affairs, Health, Care and Consumer Protection / Gesundheit Österreich GmbH, Monitoring of medical technology development. Reference period: 31st December. Coverage: - Included are all Gamma cameras units in hospitals as defined by the Austrian Hospital Act (KAKuG) and classified as HP.1 according to the System of Health Accounts (OECD). - The ambulatory sector is included (HP.3). Belgium Source of data: Federal Service of Public Health, DGGS “Organisation of health provisions”; Ministry of the Flemish community and Ministry of the French community. Coverage: - Ambulatory care providers (HP.3): Data on high-tech equipment in cabinets of ambulatory care providers are not available.
    [Show full text]
  • State-Of-The-Art Mobile Radiation Detection Systems for Different Scenarios
    sensors Review State-of-the-Art Mobile Radiation Detection Systems for Different Scenarios Luís Marques 1,* , Alberto Vale 2 and Pedro Vaz 3 1 Centro de Investigação da Academia da Força Aérea, Academia da Força Aérea, Instituto Universitário Militar, Granja do Marquês, 2715-021 Pêro Pinheiro, Portugal 2 Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais 1, 1049-001 Lisboa, Portugal; [email protected] 3 Centro de Ciências e Tecnologias Nucleares, Instituto Superior Técnico, Universidade de Lisboa, Estrada Nacional 10 (km 139.7), 2695-066 Bobadela, Portugal; [email protected] * Correspondence: [email protected] Abstract: In the last decade, the development of more compact and lightweight radiation detection systems led to their application in handheld and small unmanned systems, particularly air-based platforms. Examples of improvements are: the use of silicon photomultiplier-based scintillators, new scintillating crystals, compact dual-mode detectors (gamma/neutron), data fusion, mobile sensor net- works, cooperative detection and search. Gamma cameras and dual-particle cameras are increasingly being used for source location. This study reviews and discusses the research advancements in the field of gamma-ray and neutron measurements using mobile radiation detection systems since the Fukushima nuclear accident. Four scenarios are considered: radiological and nuclear accidents and emergencies; illicit traffic of special nuclear materials and radioactive
    [Show full text]
  • Diagnostic Radiography Is the Production of High Quality Images for the Purpose of Diagnosis of Injury Or Disease
    A Career in Medical Imaging What is Diagnostic Radiography / Medical Imaging? Diagnostic Radiography is the production of high quality images for the purpose of diagnosis of injury or disease. It is a pivotal aspect of medicine and a patient's diagnosis and ultimate treatment is often dependent on the images produced. Diagnostic Radiography uses both ionising and non-ionising radiation in the imaging process. The equipment used is at the high end of technology and computerisation within medicine. What does a Diagnostic Radiographer / Medical Imaging Technologist do? A Diagnostic Radiographer/Medical Imaging Technologist is a key member of the health care team. They are responsible for producing high quality medical images that assist medical specialists and practitioners to describe, diagnose, monitor and treat a patient’s injury or illness. Much of the medical equipment used to gain the images is highly technical and involves state of the art computerisation. A Diagnostic Radiographer/Medical Imaging Technologist needs to have the scientific and technological background to understand and use the equipment within a modern Radiology department as well as compassion and strong interpersonal skills. They need to be able to demonstrate care and understanding and have a genuine interest in a patient's welfare. The Diagnostic Radiographer/Medical Imaging Technologist will also need to be able to explain to the patient the need for the preparation and post examination care as well as the procedure to be undertaken. The Diagnostic Radiographer/Medical Imaging Technologist is able to work in a highly advanced technical profession that requires excellent people skills. It is an exciting and rewarding profession to embark on and great opportunities await the graduate.
    [Show full text]
  • Contrast-Enhanced Ultrasound Approach to the Diagnosis of Focal Liver Lesions: the Importance of Washout
    Contrast-enhanced ultrasound approach to the diagnosis of focal liver lesions: the importance of washout Hyun Kyung Yang1, Peter N. Burns2, Hyun-Jung Jang1, Yuko Kono3, Korosh Khalili1, Stephanie R. Wilson4, Tae Kyoung Kim1 REVIEW ARTICLE 1Joint Department of Medical Imaging, University of Toronto, Toronto; 2Department of https://doi.org/10.14366/usg.19006 pISSN: 2288-5919 • eISSN: 2288-5943 Medical Biophysics, Sunnybrook Research Institute, University of Toronto, Toronto, Canada; Ultrasonography 2019;38:289-301 3Departments of Medicine and Radiology, University of California, San Diego, CA, USA; 4Diagnostic Imaging, Department of Radiology, University of Calgary, Calgary, Canada Received: January 15, 2019 Contrast-enhanced ultrasound (CEUS) is a powerful technique for differentiating focal liver Revised: March 13, 2019 lesions (FLLs) without the risks of potential nephrotoxicity or ionizing radiation. In the diagnostic Accepted: March 17, 2019 algorithm for FLLs on CEUS, washout is an important feature, as its presence is highly suggestive Correspondence to: Tae Kyoung Kim, MD, PhD, FRCPC, of malignancy and its characteristics are useful in distinguishing hepatocellular from non- Department of Medical Imaging, hepatocellular malignancies. Interpreting washout on CEUS requires an understanding that Toronto General Hospital, 585 University Avenue, Toronto, ON M5G microbubble contrast agents are strictly intravascular, unlike computed tomography or magnetic 2N2, Canada resonance imaging contrast agents. This review explains the definition and types of washout on Tel. +1-416-340-3372 CEUS in accordance with the 2017 version of the CEUS Liver Imaging Reporting and Data System Fax. +1-416-593-0502 E-mail: [email protected] and presents their applications to differential diagnosis with illustrative examples.
    [Show full text]
  • Radiation and Radionuclide Measurements at Radiological and Nuclear Emergencies
    Radiation and radionuclide measurements at radiological and nuclear emergencies. Use of instruments and methods intended for clinical radiology and nuclear medicine. Ören, Ünal 2016 Document Version: Publisher's PDF, also known as Version of record Link to publication Citation for published version (APA): Ören, Ü. (2016). Radiation and radionuclide measurements at radiological and nuclear emergencies. Use of instruments and methods intended for clinical radiology and nuclear medicine. Lund University: Faculty of Medicine. Total number of authors: 1 Creative Commons License: Other General rights Unless other specific re-use rights are stated the following general rights apply: Copyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights. • Users may download and print one copy of any publication from the public portal for the purpose of private study or research. • You may not further distribute the material or use it for any profit-making activity or commercial gain • You may freely distribute the URL identifying the publication in the public portal Read more about Creative commons licenses: https://creativecommons.org/licenses/ Take down policy If you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim. LUND UNIVERSITY PO Box 117 221 00 Lund +46 46-222 00 00 Download date: 24. Sep. 2021 Radiation and radionuclide measurements at radiological and nuclear emergencies Use of instruments and methods intended for clinical radiology and nuclear medicine Ünal Ören DOCTORAL DISSERTATION by due permission of the Faculty of Medicine, Lund University, Sweden.
    [Show full text]
  • Medical Imaging, Magnetic Resonance Imaging, Advanced Technical Certificate
    Medical Imaging, Magnetic Resonance Imaging, Advanced Technical Certificate 1 MEDICAL IMAGING, MAGNETIC RESONANCE IMAGING, ADVANCED TECHNICAL CERTIFICATE Minimum Program Admission Criteria Applicants must be American Registry of Radiologic Technologies (ARRT) registered in one of the following: radiography, nuclear medicine, or radiation therapy or registry eligible and hold a Texas Medical Board Medical Radiologic Technologist license. The applicant must complete and submit an application to the Program Coordinator or Medical Imaging department. Upon provisional acceptance, the applicant must also submit required health records, proof of health insurance, CPR certification (American Heart Association-Health Care Provider), criminal background check, and drug and alcohol screen as stated for all Medical Imaging students. Acceptance into the MRI program is determined after review of the application and completion of requirements. Prospective participants should call the Medical Imaging department at 281-476-1871 for additional information. Students selected for any of the Medical Imaging programs are required to submit a physical exam after they have received provisional acceptance to the program The department will provide instructions. This physical exam must be consistent with the requirements of the teaching hospitals and agencies the student is assigned during clinical assignments and the performance standards required to function as a student imaging technologist. The exam will also include documentation of any communicable diseases along with immunity to Rubella, Measles, Mumps, Varicella, and Hepatitis B. Completion of an updated Tetanus, an annual TB screening, and the current seasonal flu vaccine are required. In addition to meeting all other requirements, students entering a Medical Imaging program will be required to submit a criminal background check and drug and alcohol screening completed by designated companies, show proof of health insurance, and CPR (American Heart Associate- Health Care Provider) certification.
    [Show full text]