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Abu-Omar A, Murray N, Ali IT, Khosa F, Barrett S, Sheikh A, Nicolaou S, O'Neill SB. The Role of Dual-Energy CT in Solid Organ Injury. Can Assoc Radiol J 2024; 75:417-427. [PMID: 38146203 DOI: 10.1177/08465371231215669] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2023] Open
Abstract
The liver, spleen, and kidneys are the commonest injured solid organs in blunt and penetrating trauma. The American Association for the Surgery of Trauma (AAST) Organ Injury Scale (OIS) is the most widely accepted system for categorizing traumatic injuries. Grading systems allow clear communication of findings between clinical teams and assign a measurable severity of injury, which directly correlates with morbidity and mortality. The 2018 revised AAST OIS emphasizes reliance on CT for accurate grading; in particular regarding vascular injuries. Dual-Energy CT (DECT) has emerged as a promising tool with multiple clinical applications already demonstrated. In this review article, we summarize the basic principles of CT attenuation to refresh the minds of our readers and we scrutinize DECT's technology as opposed to conventional Single-Energy CT (SECT). This is followed by outlining the benefits of various DECT postprocessing techniques, which authors of this article refer to as the 3Ms (Mapping of Iodine, Material decomposition, and Monoenergetic virtual imaging), in aiding radiologists to confidently assign an OIS as well as problem solve complex injury patterns. In addition, a thorough discussion of changes to the revised AAST OIS focusing on definitions of key terms used in reporting injuries is described.
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Affiliation(s)
- Ahmad Abu-Omar
- Department of Emergency Radiology, University of British Columbia, Vancouver General Hospital, Vancouver, BC, Canada
| | - Nicolas Murray
- Department of Emergency Radiology, University of British Columbia, Vancouver General Hospital, Vancouver, BC, Canada
| | - Ismail T Ali
- Department of Emergency Radiology, University of British Columbia, Vancouver General Hospital, Vancouver, BC, Canada
| | - Faisal Khosa
- Department of Emergency Radiology, University of British Columbia, Vancouver General Hospital, Vancouver, BC, Canada
| | - Sarah Barrett
- Department of Emergency Radiology, University of British Columbia, Vancouver General Hospital, Vancouver, BC, Canada
| | - Adnan Sheikh
- Department of Emergency Radiology, University of British Columbia, Vancouver General Hospital, Vancouver, BC, Canada
| | - Savvas Nicolaou
- Department of Emergency Radiology, University of British Columbia, Vancouver General Hospital, Vancouver, BC, Canada
| | - Siobhán B O'Neill
- Department of Radiology, University of Alberta, University of Alberta Hospital, Edmonton, AB, Canada
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Abu-Omar A, Murray N, Ali IT, Khosa F, Barrett S, Sheikh A, Nicolaou S, Tamburrini S, Iacobellis F, Sica G, Granata V, Saba L, Masala S, Scaglione M. Utility of Dual-Energy Computed Tomography in Clinical Conundra. Diagnostics (Basel) 2024; 14:775. [PMID: 38611688 PMCID: PMC11012177 DOI: 10.3390/diagnostics14070775] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2024] [Revised: 03/25/2024] [Accepted: 03/27/2024] [Indexed: 04/14/2024] Open
Abstract
Advancing medical technology revolutionizes our ability to diagnose various disease processes. Conventional Single-Energy Computed Tomography (SECT) has multiple inherent limitations for providing definite diagnoses in certain clinical contexts. Dual-Energy Computed Tomography (DECT) has been in use since 2006 and has constantly evolved providing various applications to assist radiologists in reaching certain diagnoses SECT is rather unable to identify. DECT may also complement the role of SECT by supporting radiologists to confidently make diagnoses in certain clinically challenging scenarios. In this review article, we briefly describe the principles of X-ray attenuation. We detail principles for DECT and describe multiple systems associated with this technology. We describe various DECT techniques and algorithms including virtual monoenergetic imaging (VMI), virtual non-contrast (VNC) imaging, Iodine quantification techniques including Iodine overlay map (IOM), and two- and three-material decomposition algorithms that can be utilized to demonstrate a multitude of pathologies. Lastly, we provide our readers commentary on examples pertaining to the practical implementation of DECT's diverse techniques in the Gastrointestinal, Genitourinary, Biliary, Musculoskeletal, and Neuroradiology systems.
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Affiliation(s)
- Ahmad Abu-Omar
- Department of Emergency Radiology, University of British Columbia, Vancouver General Hospital, Vancouver, BC V5Z 1M9, Canada (I.T.A.)
| | - Nicolas Murray
- Department of Emergency Radiology, University of British Columbia, Vancouver General Hospital, Vancouver, BC V5Z 1M9, Canada (I.T.A.)
| | - Ismail T. Ali
- Department of Emergency Radiology, University of British Columbia, Vancouver General Hospital, Vancouver, BC V5Z 1M9, Canada (I.T.A.)
| | - Faisal Khosa
- Department of Emergency Radiology, University of British Columbia, Vancouver General Hospital, Vancouver, BC V5Z 1M9, Canada (I.T.A.)
| | - Sarah Barrett
- Department of Emergency Radiology, University of British Columbia, Vancouver General Hospital, Vancouver, BC V5Z 1M9, Canada (I.T.A.)
| | - Adnan Sheikh
- Department of Emergency Radiology, University of British Columbia, Vancouver General Hospital, Vancouver, BC V5Z 1M9, Canada (I.T.A.)
| | - Savvas Nicolaou
- Department of Emergency Radiology, University of British Columbia, Vancouver General Hospital, Vancouver, BC V5Z 1M9, Canada (I.T.A.)
| | - Stefania Tamburrini
- Department of Radiology, Ospedale del Mare-ASL NA1 Centro, Via Enrico Russo 11, 80147 Naples, Italy
| | - Francesca Iacobellis
- Department of General and Emergency Radiology, A. Cardarelli Hospital, Via A. Cardarelli 9, 80131 Naples, Italy;
| | - Giacomo Sica
- Department of Radiology, Monaldi Hospital, Azienda Ospedaliera dei Colli, 80131 Naples, Italy;
| | - Vincenza Granata
- Division of Radiology, Istituto Nazionale Tumori IRCCS Fondazione Pascale—IRCCS Di Napoli, 80131 Naples, Italy
| | - Luca Saba
- Medical Oncology Department, AOU Cagliari, Policlinico Di Monserrato (CA), 09042 Monserrato, Italy
| | - Salvatore Masala
- Department of Medicine, Surgery and Pharmacy, University of Sassari, Viale S. Pietro, 07100 Sassari, Italy; (S.M.)
| | - Mariano Scaglione
- Department of Medicine, Surgery and Pharmacy, University of Sassari, Viale S. Pietro, 07100 Sassari, Italy; (S.M.)
- Department of Radiology, Pineta Grande Hospital, 81030 Castel Volturno, Italy
- Department of Radiology, James Cook University Hospital, Marton Road, Middlesbrough TS4 3BW, UK
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3
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Rajiah PS, Kambadakone A, Ananthakrishnan L, Sutphin P, Kalva SP. Vascular Applications of Dual-Energy Computed Tomography. Radiol Clin North Am 2023; 61:1011-1029. [PMID: 37758354 DOI: 10.1016/j.rcl.2023.05.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/03/2023]
Abstract
Dual- or multi-energy CT imaging provides several advantages over conventional CT in the context of vascular imaging. Specific advantages include the use of low-energy virtual monoenergetic images (VMIs) to boost iodine attenuation to salvage suboptimal enhanced studies, perform low-contrast material dose studies, and increase conspicuity of small vessels and lesions. Alternatively, high-energy VMIs reduce artifacts caused by some metals, endoprosthesis, calcium blooming, and beam hardening. Virtual non-contrast (VNC) images reduce radiation dose by eliminating the need for a true non-contrast acquisition in multiphasic CT studies. Iodine maps can be used to evaluate perfusion of tissues and lesions.
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Affiliation(s)
- Prabhakar S Rajiah
- Department of Radiology, Mayo Clinic, 200 1st Street Southwest, Rochester, MN 55905, USA.
| | | | | | - Patrick Sutphin
- Department of Radiology, Massachusetts General Hospital, Boston, MA, USA
| | - Sanjeeva P Kalva
- Department of Radiology, Massachusetts General Hospital, Boston, MA, USA
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4
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Zhao J, Cheng Q, Liu C, Wang Q, Lv Y, Tang Z, Luo Y, Yang H. Optimal combination periprosthetic vasculature visualization and metal artifact reduction by spectral computed tomography using virtual monoenergetic images in total hip arthroplasty. Insights Imaging 2023; 14:181. [PMID: 37880460 PMCID: PMC10600072 DOI: 10.1186/s13244-023-01533-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2023] [Accepted: 09/29/2023] [Indexed: 10/27/2023] Open
Abstract
OBJECTIVES To investigate the optimal parameters of spectral CT for preferably visualizing the periprosthetic vasculature and metal artifact reduction (MAR) in total hip arthroplasty (THA). METHODS A total of 34 THA of 30 patients were retrospectively included. Image reconstructions included conventional image (CI), CI combined with MAR (CIMAR), and virtual monoenergetic images (VMI) combined with MAR (VMIMAR) at 50-120 keV. The attenuation and standard deviation of the vessel and artifact, and the width of artifact were measured. Qualitative scoring was evaluated including the vascular contour, the extent of artifact, and overall diagnostic evaluation. RESULTS The attenuation, noise of the vessel and artifact, and the width of artifact decreased as the energy level increased (p < 0.001). The downtrend was relatively flat at 80-120 keV, and the vascular attenuation dropped to 200 HU at 90 keV. The qualitative rating of vascular contour was significantly higher at CIMAR (3.47) and VMIMAR 60-80 keV (2.82-3.65) compared with CI (2.03) (p ≤ 0.029), and the highest score occurred at 70 and 80 keV (3.65 and 3.56). The score of the extent of artifact was higher at VMIMAR 80 keV than CIMAR (3.53 VS 3.12, p = 0.003). The score of the overall diagnostic evaluation was higher at VMIMAR 70 and 80 keV (3.32 and 3.53, respectively) than CIMAR (3.12) (p ≤ 0.035). CONCLUSION Eighty kiloelectron volts on VMIMAR, providing satisfactorily reduced metal artifacts and improved vascular visualization, can be an optimal recommended parameter of spectrum CT for the assessment of periprosthetic vasculature in THA patients. CRITICAL RELEVANCE STATEMENT The metal artifact is gradually reducing with increasing energy level; however, the vascular visualization is worsening. The vascular visualization is terrible above 100 keV, while the vessel is disturbed by artifacts below 70 keV. The best performance is found at 80 keV. KEY POINTS • VMIMAR can provide both reduced metal artifacts and improved vascular visualization. • Eighty kiloelectron volts on VMIMAR performs best in vascular visualization of total hip arthroplasty patients. • Energy spectrum CT is recommended for routine use in patients with total hip arthroplasty.
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Affiliation(s)
- Jie Zhao
- Department of Radiology, The First Affiliated Hospital of Chongqing Medical University, 1 Youyi Road, Yuzhong District, Chongqing, 400016, China
| | - Qiang Cheng
- Department of Orthopedics, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Chuan Liu
- Department of Radiology, The First Affiliated Hospital of Chongqing Medical University, 1 Youyi Road, Yuzhong District, Chongqing, 400016, China
| | - Qiqi Wang
- Department of Radiology, The First Affiliated Hospital of Chongqing Medical University, 1 Youyi Road, Yuzhong District, Chongqing, 400016, China
| | - Yuchan Lv
- Department of Radiology, The First Affiliated Hospital of Chongqing Medical University, 1 Youyi Road, Yuzhong District, Chongqing, 400016, China
| | - Ziyi Tang
- Department of Radiology, The First Affiliated Hospital of Chongqing Medical University, 1 Youyi Road, Yuzhong District, Chongqing, 400016, China
| | - Yuxi Luo
- Department of Radiology, The First Affiliated Hospital of Chongqing Medical University, 1 Youyi Road, Yuzhong District, Chongqing, 400016, China
| | - Haitao Yang
- Department of Radiology, The First Affiliated Hospital of Chongqing Medical University, 1 Youyi Road, Yuzhong District, Chongqing, 400016, China.
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Yu HS, Keraliya A, Chakravarti S, Uyeda JW. Multienergy Computed Tomography Applications. Radiol Clin North Am 2023; 61:23-35. [DOI: 10.1016/j.rcl.2022.07.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Lacy SC, Benjamin MM, Osman M, Syed MA, Kinno M. Low Contrast and Low kV CTA Before Transcatheter Aortic Valve Replacement: A Systematic Review. J Cardiovasc Imaging 2023; 31:108-115. [PMID: 37096677 PMCID: PMC10133812 DOI: 10.4250/jcvi.2022.0108] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2022] [Revised: 12/23/2022] [Accepted: 01/03/2023] [Indexed: 02/22/2023] Open
Abstract
BACKGROUND Minimizing contrast dose and radiation exposure while maintaining image quality during computed tomography angiography (CTA) for transcatheter aortic valve replacement (TAVR) is desirable, but not well established. This systematic review compares image quality for low contrast and low kV CTA versus conventional CTA in patients with aortic stenosis undergoing TAVR planning. METHODS We performed a systematic literature review to identify clinical studies comparing imaging strategies for patients with aortic stenosis undergoing TAVR planning. The primary outcomes of image quality as assessed by the signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were reported as random effects mean difference with 95% confidence interval (CI). RESULTS We included 6 studies reporting on 353 patients. There was no difference in cardiac SNR (mean difference, -1.42; 95% CI, -5.71 to 2.88; p = 0.52), cardiac CNR (mean difference, -3.83; 95% CI, -9.98 to 2.32; p = 0.22), aortic SNR (mean difference, -0.23; 95% CI, -7.83 to 7.37; p = 0.95), aortic CNR (mean difference, -3.95; 95% CI, -12.03 to 4.13; p = 0.34), and ileofemoral SNR (mean difference, -6.09; 95% CI, -13.80 to 1.62; p = 0.12) between the low dose and conventional protocols. There was a difference in ileofemoral CNR between the low dose and conventional protocols with a mean difference of -9.26 (95% CI, -15.06 to -3.46; p = 0.002). Overall, subjective image quality was similar between the 2 protocols. CONCLUSIONS This systematic review suggests that low contrast and low kV CTA for TAVR planning provides similar image quality to conventional CTA.
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Affiliation(s)
- Spencer C. Lacy
- Department of Internal Medicine, Loyola University Medical Center, Maywood, IL, USA
| | - Mina M. Benjamin
- Division of Cardiovascular Medicine, Loyola University Medical Center, Maywood, IL, USA
| | - Mohammed Osman
- Knight & Cardiovascular Institute, Oregon Health & Science University, Portland, OR, USA
| | - Mushabbar A. Syed
- Division of Cardiovascular Medicine, Loyola University Medical Center, Maywood, IL, USA
| | - Menhel Kinno
- Division of Cardiovascular Medicine, Loyola University Medical Center, Maywood, IL, USA
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7
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Kicska GA, Hurwitz Koweek LM, Ghoshhajra BB, Beache GM, Brown RKJ, Davis AM, Hsu JY, Khosa F, Kligerman SJ, Litmanovich D, Lo BM, Maroules CD, Meyersohn NM, Rajpal S, Villines TC, Wann S, Abbara S. ACR Appropriateness Criteria® Suspected Acute Aortic Syndrome. J Am Coll Radiol 2021; 18:S474-S481. [PMID: 34794601 DOI: 10.1016/j.jacr.2021.09.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Accepted: 09/01/2021] [Indexed: 01/17/2023]
Abstract
Acute aortic syndrome (AAS) includes the entities of acute aortic dissection, intramural hematoma, and penetrating atherosclerotic ulcer. AAS typically presents with sudden onset of severe, tearing, anterior, or interscapular back pain. Symptoms may be dominated by malperfusion syndrome, due to obstruction of the lumen of the aorta and/or a side branch when the intimal and medial layers are separated. Timely diagnosis of AAS is crucial to permit prompt management; for example, early mortality rates are reported to be 1% to 2% per hour after the onset of symptoms for untreated ascending aortic dissection. The appropriateness assigned to each imaging procedure was based on the ability to obtain key information that is used to plan open surgical, endovascular, or medical therapy. This includes, but is not limited to, confirming the presence of AAS; classification; characterization of entry and reentry sites; false lumen patency; and branch vessel compromise. Using this approach, CT, CTA, and MRA are all considered usually appropriate in the initial evaluation of AAS if those procedures include intravenous contrast administration. Ultrasound is also considered usually appropriate if the acquisition is via a transesophageal approach. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.
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Affiliation(s)
| | | | - Brian B Ghoshhajra
- Panel Vice-Chair, Massachusetts General Hospital, Boston, Massachusetts; Executive Committee, Society of Cardiovascular Computed Tomography
| | - Garth M Beache
- University of Louisville School of Medicine, Louisville, Kentucky
| | | | - Andrew M Davis
- Associate Vice-Chair, Quality, Department of Medicine, The University of Chicago Medical Center, Chicago, Illinois; and American College of Physicians
| | - Joe Y Hsu
- Kaiser Permanente, Los Angeles, California
| | - Faisal Khosa
- Vancouver General Hospital, Vancouver, British Columbia, Canada; and Co-Chair of Equity, Diversity and Inclusion Committee, UBC
| | | | - Diana Litmanovich
- Harvard Medical School, Boston, Massachusetts; and Past-President, NASCI
| | - Bruce M Lo
- Sentara Norfolk General/Eastern Virginia Medical School, Norfolk, Virginia; Board Member, American Academy of Emergency Medicine; and American College of Emergency Physicians
| | | | - Nandini M Meyersohn
- Massachusetts General Hospital, Boston, Massachusetts; and AMA Delegate, RSNA
| | - Saurabh Rajpal
- Ohio State University, Nationwide Children's Hospital, Columbus, Ohio; Society for Cardiovascular Magnetic Resonance
| | - Todd C Villines
- University of Virginia Health Center, Charlottesville, Virginia; Society of Cardiovascular Computed Tomography
| | - Samuel Wann
- Ascension Healthcare Wisconsin, Milwaukee, Wisconsin; Nuclear cardiology expert
| | - Suhny Abbara
- Specialty Chair, UT Southwestern Medical Center, Dallas, Texas; and BOD SCCT
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Abstract
Computed tomography angiography (CTA) has become a mainstay for the imaging of vascular diseases, because of high accuracy, availability, and rapid turnaround time. High-quality CTA images can now be routinely obtained with high isotropic spatial resolution and temporal resolution. Advances in CTA have focused on improving the image quality, increasing the acquisition speed, eliminating artifacts, and reducing the doses of radiation and iodinated contrast media. Dual-energy computed tomography provides material composition capabilities that can be used for characterizing lesions, optimizing contrast, decreasing artifact, and reducing radiation dose. Deep learning techniques can be used for classification, segmentation, quantification, and image enhancement.
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Affiliation(s)
- Prabhakar Rajiah
- Department of Radiology, Mayo Clinic, 200 1st Street SW, Rochester, MN 55904, USA.
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9
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Cavallo AU, Patterson AJ, Thomas R, Alaiti MA, Attizzani GF, Laukamp K, Große Hokamp N, Bezerra H, Gilkeson R, Rajagopalan S. Low dose contrast CT for transcatheter aortic valve replacement assessment: Results from the prospective SPECTACULAR study (spectral CT assessment prior to TAVR). J Cardiovasc Comput Tomogr 2020; 14:68-74. [DOI: 10.1016/j.jcct.2019.06.015] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/06/2019] [Revised: 06/06/2019] [Accepted: 06/23/2019] [Indexed: 11/16/2022]
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10
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Murray N, Darras KE, Walstra FE, Mohammed MF, McLaughlin PD, Nicolaou S. Dual-Energy CT in Evaluation of the Acute Abdomen. Radiographics 2019; 39:264-286. [DOI: 10.1148/rg.2019180087] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Nicolas Murray
- From the Department of Radiology, Vancouver General Hospital, University of British Columbia, 899 W 12th Ave, Vancouver, BC, Canada V5Z 1M9 (N.M., K.E.D., F.E.W., P.D.M., S.N.); and the Medical Imaging Department, King Saud bin Abdulaziz University for Health Sciences, King Abdullah International Medical Research Center, Ministry of the National Guard, Health Affairs, Riyadh, Saudi Arabia (M.F.M.)
| | - Kathryn E. Darras
- From the Department of Radiology, Vancouver General Hospital, University of British Columbia, 899 W 12th Ave, Vancouver, BC, Canada V5Z 1M9 (N.M., K.E.D., F.E.W., P.D.M., S.N.); and the Medical Imaging Department, King Saud bin Abdulaziz University for Health Sciences, King Abdullah International Medical Research Center, Ministry of the National Guard, Health Affairs, Riyadh, Saudi Arabia (M.F.M.)
| | - Frances E. Walstra
- From the Department of Radiology, Vancouver General Hospital, University of British Columbia, 899 W 12th Ave, Vancouver, BC, Canada V5Z 1M9 (N.M., K.E.D., F.E.W., P.D.M., S.N.); and the Medical Imaging Department, King Saud bin Abdulaziz University for Health Sciences, King Abdullah International Medical Research Center, Ministry of the National Guard, Health Affairs, Riyadh, Saudi Arabia (M.F.M.)
| | - Mohammed F. Mohammed
- From the Department of Radiology, Vancouver General Hospital, University of British Columbia, 899 W 12th Ave, Vancouver, BC, Canada V5Z 1M9 (N.M., K.E.D., F.E.W., P.D.M., S.N.); and the Medical Imaging Department, King Saud bin Abdulaziz University for Health Sciences, King Abdullah International Medical Research Center, Ministry of the National Guard, Health Affairs, Riyadh, Saudi Arabia (M.F.M.)
| | - Patrick D. McLaughlin
- From the Department of Radiology, Vancouver General Hospital, University of British Columbia, 899 W 12th Ave, Vancouver, BC, Canada V5Z 1M9 (N.M., K.E.D., F.E.W., P.D.M., S.N.); and the Medical Imaging Department, King Saud bin Abdulaziz University for Health Sciences, King Abdullah International Medical Research Center, Ministry of the National Guard, Health Affairs, Riyadh, Saudi Arabia (M.F.M.)
| | - Savvas Nicolaou
- From the Department of Radiology, Vancouver General Hospital, University of British Columbia, 899 W 12th Ave, Vancouver, BC, Canada V5Z 1M9 (N.M., K.E.D., F.E.W., P.D.M., S.N.); and the Medical Imaging Department, King Saud bin Abdulaziz University for Health Sciences, King Abdullah International Medical Research Center, Ministry of the National Guard, Health Affairs, Riyadh, Saudi Arabia (M.F.M.)
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Abstract
Multidetector-row computed tomography (MDCT) can provide crucial information and rapid triage of emergency department patients with suspected acute coronary syndrome (ACS) or acute aortic syndrome (AAS). Coronary computed tomography angiography has high negative predictive value to rule out ACS, and MDCT is diagnostic for AAS and its variants. Optimization of acquisition technique and up-to-date knowledge of the pathophysiology of these conditions can improve study and interpretation quality for diagnosis of ACS or AAS.
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Affiliation(s)
- Avanti Gulhane
- Cardiovascular Imaging, Department of Radiology, Perelman School of Medicine, University of Pennsylvania, 1 Silverstein, 3400 Spruce Street, Philadelphia, PA 19104, USA
| | - Harold Litt
- Cardiothoracic Imaging Division, Department of Radiology, Perelman School of Medicine, University of Pennsylvania, 1 Silverstein, 3400 Spruce Street, Philadelphia, PA 19104, USA.
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13
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Noise characteristics of virtual monoenergetic images from a novel detector-based spectral CT scanner. Eur J Radiol 2017; 98:118-125. [PMID: 29279149 DOI: 10.1016/j.ejrad.2017.11.005] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2017] [Revised: 11/02/2017] [Accepted: 11/09/2017] [Indexed: 11/24/2022]
Abstract
AIM To evaluate the noise characteristics of virtual monoenergetic images (VMI) obtained from a recently introduced dual-layer detector-based spectral CT (SDCT), both in a phantom and patients. MATERIALS AND METHODS A cylindrical Catphan® 600 phantom (The Phantom Library, Salem NY, USA) was scanned using the SDCT. Image noise, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) were measured in VMI from 40 to 200keV as well as conventional 120 kVp images. One hundred consecutive patients who had an abdominal CT on the SDCT were then recruited in the study. Noise, SNR and CNR were measured in the liver, pancreas, spleen, kidney, abdominal aorta, portal vein, muscle, bone, and fat, both in VMI (40-200 keV) and conventional 120kVp images. Qualitative image analysis was performed by an independent reader for vascular enhancement and image quality on a 5 point scale (1-worst, 5-best). RESULTS On phantom studies, noise was low at all energies of VMI. Noise was highest at 40keV (5.3±0.2 HU), gradually decreased up to 70keV (3.6±0.2 HU), after which it remained constant up to 200keV (3.5±0.2 HU). In the patient cohort, noise was low (<25 HU) at all the energy levels of VMI for all the regions, with the exception of bone. For example, noise in the liver was highest at 40keV (13.2±4.6 HU), steadily decreased up to 70keV (12.0±4.4 HU) and then remained constantly low up to 200keV (11.6±4.3HU). For liver, pancreas, portal vein, aorta, muscle and fat, noise at all levels of VMI was lower than of conventional images (p<0.01). For all organs, SNR, and CNR were highest at 40keV (6.8-34.9; 18.3-44.9, respectively) after which they gradually decreased up to 120keV (3.4-6.5; 9.5-13.0) and then remained constant to 200keV (2.6-5.5; 8.5-12.5). Qualitative scores of VMI up to 70keV were significantly higher than the conventional images (p≤0.01), whereas for VMI≥80keV, they were lower than conventional images (p<0.001). CONCLUSION VMI obtained from the novel SDCT scanner have low noise across the entire spectrum of energies. There are significant SNR and CNR improvements compared to conventional 120 kVp images.
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14
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Kalisz K, Halliburton S, Abbara S, Leipsic JA, Albrecht MH, Schoepf UJ, Rajiah P. Update on Cardiovascular Applications of Multienergy CT. Radiographics 2017; 37:1955-1974. [DOI: 10.1148/rg.2017170100] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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15
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Effectiveness of Adaptive Statistical Iterative Reconstruction for 64-Slice Dual-Energy Computed Tomography Pulmonary Angiography in Patients With a Reduced Iodine Load: Comparison With Standard Computed Tomography Pulmonary Angiography. J Comput Assist Tomogr 2017; 40:777-83. [PMID: 27454785 DOI: 10.1097/rct.0000000000000443] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE The aim of the study was to assess the effectiveness of the adaptive statistical iterative reconstruction (ASIR) for dual-energy computed tomography pulmonary angiography (DE-CTPA) with a reduced iodine load. MATERIALS AND METHODS One hundred forty patients referred for chest CT were randomly divided into a DE-CTPA group with a reduced iodine load or a standard CTPA group. Quantitative and qualitative image qualities of virtual monochromatic spectral (VMS) images with filtered back projection (VMS-FBP) and those with 50% ASIR (VMS-ASIR) in the DE-CTPA group were compared. Image qualities of VMS-ASIR images in the DE-CTPA group and ASIR images in the standard CTPA group were also compared. RESULTS All quantitative and qualitative indices, except attenuation value of pulmonary artery in the VMS-ASIR subgroup, were superior to those in the VMS-FBP subgroup (all P < 0.001). Noise and signal-to-noise ratio of VMS-ASIR images were superior to those of ASIR images in the standard CTPA group (P < 0.001 and P = 0.007, respectively). Regarding qualitative indices, noise was significantly lower in VMS-ASIR images of the DE-CTPA group than in ASIR images of the standard CTPA group (P = 0.001). CONCLUSIONS The ASIR technique tends to improve the image quality of VMS imaging. Dual-energy computed tomography pulmonary angiography with ASIR can reduce contrast medium volume and produce images of comparable quality with those of standard CTPA.
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Haji-Momenian S, Rischall J, Okey N, Taffel M, Khati N, Zeman R. CT of suspected thoracic acute aortic injury in the emergency department: is routine abdominopelvic imaging worth the additional collective radiation dose? Emerg Radiol 2016; 24:13-20. [PMID: 27568394 DOI: 10.1007/s10140-016-1435-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2016] [Accepted: 08/16/2016] [Indexed: 10/21/2022]
Abstract
This study aimed to determine the incidence of non-traumatic acute aortic injury (AAI) extending from the chest into the abdomen or pelvis in emergency department (ED) patients with acute aortic syndrome (AAS), to estimate the effective dose of the abdominopelvic portion of these CT exams, and to compare the number needed to screen (NNS) with the collective population radiation dose of imaging those stations. All patients (n = 238) presenting to the ED with AAS between March 2014 and June 2015 who were imaged per CT AAI protocol (noncontrast and contrast-enhanced CT angiography of the chest, abdomen, and pelvis) were retrospectively identified in this IRB-approved HIPAA-compliant study. The Stanford classification for positive cases of AAI was further subclassified based on chest, abdominal, or pelvic involvement. The dose length product (DLP) of each exam was used to estimate the dose of the abdominal and pelvic stations and the collective effective dose for the population. There were five cases of aortic dissection (AD) and two of intramural hematoma (IMH), with an AAI incidence of 2.9/100. Three cases of AAI were confined to the chest. Two cases of AAI were confined to the chest and abdomen, and two cases involved the chest, abdomen, and pelvis. There was only one case of AAI involving the ascending aorta that extended into the abdomen or pelvis. The number needed to screen to identify (a) AAI extending from the chest into the abdomen or pelvis was 59.5 and (b) Stanford A AAI extending into the abdomen or pelvis was 238. The estimated mean effective dose for the abdominopelvic stations were unenhanced abdomen 2.3 mSv, unenhanced pelvis 3.3 mSv, abdominal CTA 2.5 mSv, and pelvic CTA 3.6 mSv. The collective effective doses to the abdomen and pelvis with unenhanced CT and CTA in 59.5 patients and 238 patients were 761.6 and 3046.4 mSv, respectively. While the estimated mean effective dose for imaging of the abdominopelvic stations are low, the collective effective dose should also be considered. It may be beneficial to modify or omit routine unenhanced CT and/or CTA of the abdomen/pelvis in this patient population in the absence of abdominal symptoms, and image the abdomen and pelvis in positive thoracic cases only.
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Affiliation(s)
- Shawn Haji-Momenian
- Department of Radiology, The George Washington University Medical Faculty Associates, George Washington University Hospital, 900 23rd St NW, Washington, DC, 20037, USA.
| | - Jonathan Rischall
- The George Washington University School of Medicine, 2300 I St NW, Washington, DC, 20052, USA
| | - Neil Okey
- The George Washington University School of Medicine, 2300 I St NW, Washington, DC, 20052, USA
| | - Myles Taffel
- Department of Radiology, The George Washington University Medical Faculty Associates, George Washington University Hospital, 900 23rd St NW, Washington, DC, 20037, USA
| | - Nadia Khati
- Department of Radiology, The George Washington University Medical Faculty Associates, George Washington University Hospital, 900 23rd St NW, Washington, DC, 20037, USA
| | - Robert Zeman
- Department of Radiology, The George Washington University Medical Faculty Associates, George Washington University Hospital, 900 23rd St NW, Washington, DC, 20037, USA
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Carotid dual-energy CT angiography: Evaluation of low keV calculated monoenergetic datasets by means of a frequency-split approach for noise reduction at low keV levels. Eur J Radiol 2016; 85:720-5. [PMID: 26971414 DOI: 10.1016/j.ejrad.2016.01.015] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2015] [Revised: 01/14/2016] [Accepted: 01/18/2016] [Indexed: 11/23/2022]
Abstract
BACKGROUND AND PURPOSE Calculated monoenergetic ultra-low keV datasets did not lead to improved contrast-to-noise ratio (CNR) due to the dramatic increase in image noise. The aim of the present study was to evaluate the objective image quality of ultra-low keV monoenergetic images (MEIs) calculated from carotid DECT angiography data with a new monoenergetic imaging algorithm using a frequency-split technique. MATERIALS AND METHODS 20 patients (12 male; mean age 53±17 years) were retrospectively analyzed. MEIs from 40 to 120 keV were reconstructed using the monoenergetic split frequency approach (MFSA). Additionally MEIs were reconstructed for 40 and 50 keV using a conventional monoenergetic (CM) software application. Signal intensity, noise, signal-to-noise ratio (SNR) and CNR were assessed in the basilar, common, internal carotid arteries. RESULTS Ultra-low keV MEIs at 40 keV and 50 keV demonstrated highest vessel attenuation, significantly greater than those of the polyenergetic images (PEI) (all p-values <0.05). The highest SNR level and CNR level was found at 40 keV and 50 keV (all p-values <0.05). MEIs with MFSA showed significantly lower noise levels than those processed with CM (all p-values <0.05) and no significant differences in vessel attenuation (p>0.05). Thus MEIs with MFSA showed significantly higher SNR and CNR compared to MEIs with CM. CONCLUSION Combining the lower spatial frequency stack for contrast at low keV levels with the high spatial frequency stack for noise at high keV levels (frequency-split technique) leads to improved image quality of ultra-low keV monoenergetic DECT datasets when compared to previous monoenergetic reconstruction techniques without the frequency-split technique.
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Godoy MCB. Invited commentary on "Dual-energy CT for imaging of pulmonary hypertension". Radiographics 2014; 34:1791-2. [PMID: 25384278 DOI: 10.1148/rg.347140256] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Myrna Cobos Barco Godoy
- Department of Diagnostic Radiology, University of Texas MD Anderson Cancer Center Houston, Texas
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Abstract
OBJECTIVE Recent technologic advances in MDCT have led to the introduction of dual-energy CT (DECT). The basic principle of DECT is to acquire images at two different energy levels simultaneously and to use the attenuation differences at these different energy levels for deriving additional information, such as virtual monochromatic images, artifact suppression, and material composition of various tissues. CONCLUSION A variety of image reconstruction and postprocessing techniques are available for better demonstration and characterization of pathologic abnormalities. DECT can provide both anatomic and functional information of different organ systems. This article focuses on the main applications of DECT in emergency radiology.
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Schneider D, Apfaltrer P, Sudarski S, Nance JW, Haubenreisser H, Fink C, Schoenberg SO, Henzler T. Optimization of kiloelectron volt settings in cerebral and cervical dual-energy CT angiography determined with virtual monoenergetic imaging. Acad Radiol 2014; 21:431-6. [PMID: 24594412 DOI: 10.1016/j.acra.2013.12.006] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2013] [Revised: 12/14/2013] [Accepted: 12/15/2013] [Indexed: 10/25/2022]
Abstract
RATIONALE AND OBJECTIVES Dual-energy computed tomography (DECT) offers various fields of application, especially in angiography using virtual monoenergetic imaging. The aim of this study was to evaluate objective image quality indices of calculated low-kiloelectron volt monoenergetic DECT angiographic cervical and cerebral data sets compared to virtual 120-kV polyenergetic images. MATERIALS AND METHODS Forty-one patients (21 men, mean age 58 ± 14) who underwent DECT angiography of the cervical (n = 7) or cerebral vessels (n = 34) were retrospectively included in this study. Data acquired with the 80 and 140 kVp tube using dual-source CT technology were subsequently used to calculate low-kiloelectron volt monoenergetic image data sets ranging from 120 to 40 keV (at 10-keV intervals per patient). Vessel and soft tissue attenuation and image noise were measured in various regions of interest, and contrast-to-noise ratio (CNR) was subsequently calculated. Differences in image attenuation and CNR were compared between the different monoenergetic data sets and virtual 120-kV polyenergetic images. RESULTS For cervical angiography, 60-keV monoenergetic data sets resulted in the greatest improvements in vessel attenuation and CNR compared to virtual 120-kV polyenergetic data sets (+40%, +16%; all P < .01). Also for cerebral vessel assessment, 60-keV monoenergetic data sets provided the greatest improvement in vessel attenuation and CNR (+40%, +9%; all P < .01) compared to virtual 120-kV polyenergetic data sets. CONCLUSIONS 60-keV monoenergetic image data significantly improve vessel attenuation and CNR of cervical and cerebral DECT angiographic studies. Future studies have to evaluate whether the technique can lead to an increased diagnostic accuracy or should be used for dose reduction of iodinated contrast material.
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Sudarski S, Apfaltrer P, Nance JW, Meyer M, Fink C, Hohenberger P, Leidecker C, Schoenberg SO, Henzler T. Objective and subjective image quality of liver parenchyma and hepatic metastases with virtual monoenergetic dual-source dual-energy CT reconstructions: an analysis in patients with gastrointestinal stromal tumor. Acad Radiol 2014; 21:514-22. [PMID: 24594421 DOI: 10.1016/j.acra.2014.01.001] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2013] [Revised: 12/10/2013] [Accepted: 01/07/2014] [Indexed: 12/12/2022]
Abstract
RATIONALE AND OBJECTIVES To compare in dual-energy CT (DECT) conventionally reconstructed polyenergetic images (PEI) at 120 kVp to virtual monoenergetic images (MEI) at different kiloelectron volt (keV) levels for evaluation of liver and gastrointestinal stromal tumor (GIST) hepatic metastases with regard to objective (IQob) and subjective image quality (IQsub) assessed by two readers of varying experience. Image quality was correlated to patient size and compared between PEI and MEI. MATERIALS AND METHODS From 50 examinations of 17 GIST patients (12 with hepatic metastases) undergoing abdominal dual-source DECT for staging, therapy monitoring or follow-up, PEI and nine MEI in 10-keV intervals from 40 to 120 keV were reconstructed. Liver contrast-to-noise ratios (CNR) and metastasis-to-liver ratios were calculated. MEI reconstructions with the highest IQob were compared to PEI for IQsub by one experienced reader (ER) and one inexperienced reader (IR). Patients' diameters were correlated to IQob and IQsub ratings. RESULTS MEI at 70 keV had the highest IQob with equal liver CNR and metastasis-to-liver ratio compared to PEI. The ER rated 70-keV MEI and PEI equally high (median 4), whereas the IR rated IQsub best in 70-keV MEI (median 5). Unlike in PEI, IQsub ratings in 70-keV MEI were not correlated to patient size. CONCLUSIONS MEI at 70 keV provided an IQob equivalent to PEI. Regarding the IR, IQsub was improved in 70-keV MEI compared to PEI and less dependent on patient size. Therefore, IRs might improve their diagnostic confidence in the assessment of hepatic GIST metastases by evaluating MEI reconstructions at 70 keV.
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Aran S, Shaqdan KW, Abujudeh HH. Dual-energy computed tomography (DECT) in emergency radiology: basic principles, techniques, and limitations. Emerg Radiol 2014; 21:391-405. [DOI: 10.1007/s10140-014-1208-2] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2014] [Accepted: 02/17/2014] [Indexed: 02/05/2023]
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Imaging Follow-up of Endovascular Repair of Type B Aortic Dissection with Dual-Source, Dual-Energy CT and Late Delayed-Phase Scans. J Vasc Interv Radiol 2014; 25:435-42. [DOI: 10.1016/j.jvir.2013.11.026] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2013] [Revised: 11/19/2013] [Accepted: 11/23/2013] [Indexed: 11/24/2022] Open
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Del Gaizo AJ, Silva AC, Hara AK. The utility of dual-energy computed tomography in abdominal imaging. APPLIED RADIOLOGY 2014. [DOI: 10.37549/ar2048] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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Stein E, Mueller GC, Sundaram B. Thoracic Aorta (Multidetector Computed Tomography and Magnetic Resonance Evaluation). Radiol Clin North Am 2014; 52:195-217. [DOI: 10.1016/j.rcl.2013.08.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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Sudarski S, Apfaltrer P, Nance JW, Schneider D, Meyer M, Schoenberg SO, Fink C, Henzler T. Optimization of keV-settings in abdominal and lower extremity dual-source dual-energy CT angiography determined with virtual monoenergetic imaging. Eur J Radiol 2013; 82:e574-81. [PMID: 23763858 DOI: 10.1016/j.ejrad.2013.04.040] [Citation(s) in RCA: 88] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2013] [Revised: 04/22/2013] [Accepted: 04/23/2013] [Indexed: 12/13/2022]
Abstract
OBJECTIVES To compare objective image quality indices in dual-energy CT angiography (DE-CTA) studies of the abdomen and lower extremity using conventional polyenergetic images (PEIs) and virtual monoenergetic images (MEIs) at different kiloelectron volt (keV) levels. METHODS We retrospectively evaluated 68 dual-source DE-CTA studies. 50 patients (42 men, 71 ± 10 years) underwent abdominal DE-CTA. 18 patients (13 men, 67 ± 10 years) underwent lower extremity DE-CTA. MEIs from 40 to 120 keV were reconstructed. Signal intensity, noise, signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were assessed in infrarenal aorta, superior mesenteric, external iliac, femoral, popliteal, and lower leg arteries. Comparisons between MEIs and PEIs were performed with Dunnett's test. RESULTS 222 arteries were evaluated. In abdominal arteries 70 keV MEIs showed statistically equal signal intensity, noise and CNR levels (+13%; +31%, -14% on average; all p>0.05) compared to PEIs; SNR was equal or slightly impaired (-7% on average; p<0.001-1.00). In lower extremity arteries 60 keV MEIs resulted in significantly higher signal intensity and CNR (+54%; +54% on average; all p<0.05) compared to PEIs at equal noise levels (+18% on average; all p>0.05) and equal or higher SNR (+49% on average; p<0.01-0.35). CONCLUSIONS Low-keV MEIs lead to equal or higher signal intensity and CNR compared to PEIs. In lower extremity DE-CTA, additional reconstruction of low-keV MEIs at 60 keV might increase diagnostic confidence.
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Affiliation(s)
- Sonja Sudarski
- Institute of Clinical Radiology and Nuclear Medicine, University Medical Center Mannheim, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany.
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Sodickson A. Strategies for Reducing Radiation Exposure from Multidetector Computed Tomography in the Acute Care Setting. Can Assoc Radiol J 2013; 64:119-29. [DOI: 10.1016/j.carj.2013.01.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2012] [Accepted: 01/21/2013] [Indexed: 11/28/2022] Open
Abstract
Many tools and strategies exist to enable reduction of radiation exposure from computed tomography (CT). The common CT metrics of x-ray output, the volume CT dose index and the dose-length product, are explained and serve as the basis for monitoring radiation exposure from CT. Many strategies to dose-optimize CT protocols are explored that, in combination with available hardware and software tools, allow robust diagnostic quality CT to be performed with a radiation exposure appropriate for the clinical scenario and the size of the patient. Specific emergency department example protocols are used to demonstrate these techniques.
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Affiliation(s)
- Aaron Sodickson
- Emergency Radiology, Brigham and Women's Hospital, Boston, Massachusetts, USA Harvard Medical School, Boston, Massachusetts, USA
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Endoleak Detection After Endovascular Repair of Thoracic Aortic Aneurysm Using Dual-Source Dual-Energy CT: Suitable Scanning Protocols and Potential Radiation Dose Reduction. AJR Am J Roentgenol 2013; 200:451-60. [DOI: 10.2214/ajr.11.8033] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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Abstract
OBJECTIVE Dual-energy CT permits a variety of image reconstructions for the depiction and characterization of vascular disease. Techniques include visualization of low- and high-peak-kilovoltage spectra image datasets and also material-specific reconstructions combining both low- and high-peak-kilovoltage data. CONCLUSION This article focuses on four main vascular areas: the aorta, the major visceral, lower limb, and cervical arteries. For each territory, the current status, potential advantages, and limitations of these techniques are described.
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CT Angiography of the Aorta and Aortic Diseases. CURRENT CARDIOVASCULAR IMAGING REPORTS 2012. [DOI: 10.1007/s12410-012-9156-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Kobayashi H, Longmire MR, Ogawa M, Choyke PL. Rational chemical design of the next generation of molecular imaging probes based on physics and biology: mixing modalities, colors and signals. Chem Soc Rev 2011; 40:4626-48. [PMID: 21607237 PMCID: PMC3417232 DOI: 10.1039/c1cs15077d] [Citation(s) in RCA: 180] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
In recent years, numerous in vivo molecular imaging probes have been developed. As a consequence, much has been published on the design and synthesis of molecular imaging probes focusing on each modality, each type of material, or each target disease. More recently, second generation molecular imaging probes with unique, multi-functional, or multiplexed characteristics have been designed. This critical review focuses on (i) molecular imaging using combinations of modalities and signals that employ the full range of the electromagnetic spectra, (ii) optimized chemical design of molecular imaging probes for in vivo kinetics based on biology and physiology across a range of physical sizes, (iii) practical examples of second generation molecular imaging probes designed to extract complementary data from targets using multiple modalities, color, and comprehensive signals (277 references).
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Affiliation(s)
- Hisataka Kobayashi
- Molecular Imaging Program, National Cancer Institute/NIH, Bldg. 10, Room B3B69, MSC 1088, 10 Center Dr Bethesda, Maryland 20892-1088, USA.
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Influence of coronary calcification on the diagnostic accuracy of 64-slice computed tomography coronary angiography: a systematic review and meta-analysis. Int J Cardiovasc Imaging 2011; 28:943-53. [DOI: 10.1007/s10554-011-9902-6] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/25/2011] [Accepted: 05/25/2011] [Indexed: 11/25/2022]
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