1
|
Contrella BN, Khaja MS, Majdalany BS, Kim CY, Kalva SP, Beck AW, Browne WF, Clough RE, Ferencik M, Fleischman F, Gunn AJ, Hickey SM, Kandathil A, Kim KM, Monroe EJ, Ochoa Chaar CI, Scheidt MJ, Smolock AR, Steenburg SD, Waite K, Pinchot JW, Steigner ML. ACR Appropriateness Criteria® Thoracoabdominal Aortic Aneurysm or Dissection: Treatment Planning and Follow-Up. J Am Coll Radiol 2023; 20:S265-S284. [PMID: 37236748 DOI: 10.1016/j.jacr.2023.02.007] [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] [Received: 02/21/2023] [Accepted: 02/27/2023] [Indexed: 05/28/2023]
Abstract
As the incidence of thoracoabdominal aortic pathology (aneurysm and dissection) rises and the complexity of endovascular and surgical treatment options increases, imaging follow-up of patients remains crucial. Patients with thoracoabdominal aortic pathology without intervention should be monitored carefully for changes in aortic size or morphology that could portend rupture or other complication. Patients who are post endovascular or open surgical aortic repair should undergo follow-up imaging to evaluate for complications, endoleak, or recurrent pathology. Considering the quality of diagnostic data, CT angiography and MR angiography are the preferred imaging modalities for follow-up of thoracoabdominal aortic pathology for most patients. The extent of thoracoabdominal aortic pathology and its potential complications involve multiple regions of the body requiring imaging of the chest, abdomen, and pelvis in most patients. The ACR Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision process support the systematic analysis of the medical literature from peer reviewed journals. Established methodology principles such as Grading of Recommendations Assessment, Development, and Evaluation or GRADE are adapted to evaluate the evidence. The RAND/UCLA Appropriateness Method User Manual provides the methodology to determine the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where peer reviewed literature is lacking or equivocal, experts may be the primary evidentiary source available to formulate a recommendation.
Collapse
Affiliation(s)
| | | | - Bill S Majdalany
- Panel Chair, University of Vermont Medical Center, Burlington, Vermont
| | - Charles Y Kim
- Panel Chair, Duke University Medical Center, Durham, North Carolina
| | - Sanjeeva P Kalva
- Panel Vice-Chair, Massachusetts General Hospital, Boston, Massachusetts
| | - Adam W Beck
- University of Alabama at Birmingham Medical Center, Birmingham, Alabama; Society for Vascular Surgery
| | | | - Rachel E Clough
- St Thomas' Hospital, King's College, School of Biomedical Engineering and Imaging Science, London, United Kingdom; Society for Cardiovascular Magnetic Resonance
| | - Maros Ferencik
- Knight Cardiovascular Institute, Oregon Health & Science University, Portland, Oregon; Society of Cardiovascular Computed Tomography
| | - Fernando Fleischman
- Keck School of Medicine of USC, Los Angeles, California; American Association for Thoracic Surgery
| | - Andrew J Gunn
- University of Alabama at Birmingham, Birmingham, Alabama
| | - Sean M Hickey
- David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California; American College of Emergency Physicians
| | - Asha Kandathil
- UT Southwestern Medical Center, Dallas, Texas; Commission on Nuclear Medicine and Molecular Imaging
| | - Karen M Kim
- University of Michigan, Ann Arbor, Michigan; The Society of Thoracic Surgeons
| | | | | | | | - Amanda R Smolock
- Froedtert & The Medical College of Wisconsin, Milwaukee, Wisconsin
| | - Scott D Steenburg
- Indiana University School of Medicine and Indiana University Health, Indianapolis, Indiana; Committee on Emergency Radiology-GSER
| | - Kathleen Waite
- Duke University Medical Center, Durham, North Carolina, Primary care physician
| | - Jason W Pinchot
- Specialty Chair, University of Wisconsin, Madison, Wisconsin
| | | |
Collapse
|
2
|
Kessner R, Sommer J, Große Hokamp N, Laukamp KR, Nayate A. Virtual versus true non-contrast images of the brain from spectral detector CT: comparison of attenuation values and image quality. Acta Radiol 2023; 64:776-783. [PMID: 35505585 DOI: 10.1177/02841851221093763] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Prior studies focused on utilization of dual-energy computed tomography (DECT) to better detect intracranial pathology and to reduce artifacts. It is still unclear whether virtual non-contrast (VNC) images of DECT can replace true non-contrast (TNC) images. PURPOSE To compare attenuation values and image quality of VNC images to TNC images of the brain, obtained using spectral detector CT (SDCT). MATERIAL AND METHODS We retrospectively evaluated patients that underwent head CT with and without contrast material, on a SDCT scanner at our institution (n = 33). The attenuation values of different brain structures were obtained from TNC images, the conventional images of the post-contrast exams (n = 16) or the CT angiography (CTA) (n = 17), and the derived VNC images. In total, 591 regions of interest were obtained, including white and gray matter. Two neuroradiologists independently evaluated the image quality of the VNC and TNC images, using a 5-point Likert scale. RESULTS The mean difference between the attenuation values on the VNC versus the TNC images was <4 HU for almost all the structures. The difference reached statistical significance (P < 0.05) for the deep gray structures but not for the white matter. The image quality score of the TNC images was 5 in all the patients (excellent gray-white matter differentiation). The scores of the VNC images differed between post-contrast and CTA examinations, with means of 4.9 ± 0.3 (excellent) and 3.2 ± 0.4 (fair), respectively (P < 0.001). CONCLUSION Our results show minor differences between attenuation values of different brain structures on VNC versus TNC images of SDCT.
Collapse
Affiliation(s)
- Rivka Kessner
- Department of Radiology, University Hospitals Cleveland Medical Center and Case Western Reserve University, Cleveland, OH, USA.,Department of Diagnostic Imaging, Sackler Faculty of Medicine, 26745Tel Aviv University, Ramat Aviv, Israel
| | - Jennifer Sommer
- Department of Radiology, University Hospitals Cleveland Medical Center and Case Western Reserve University, Cleveland, OH, USA
| | - Nils Große Hokamp
- Department of Radiology, University Hospitals Cleveland Medical Center and Case Western Reserve University, Cleveland, OH, USA.,27182University Hospital Cologne, Institute for Diagnostic and Interventional Radiology, Cologne, Germany
| | - Kai R Laukamp
- Department of Radiology, University Hospitals Cleveland Medical Center and Case Western Reserve University, Cleveland, OH, USA.,27182University Hospital Cologne, Institute for Diagnostic and Interventional Radiology, Cologne, Germany
| | - Ameya Nayate
- Department of Radiology, University Hospitals Cleveland Medical Center and Case Western Reserve University, Cleveland, OH, USA
| |
Collapse
|
3
|
Lee MH, Park HJ, Kim JN, Kim MS, Hong SW, Park JH, Kang CH. Virtual non-contrast images from dual-energy CT angiography of the abdominal aorta and femoral arteries: comparison with true non-contrast CT images. Br J Radiol 2022; 95:20220378. [PMID: 36039820 PMCID: PMC9815733 DOI: 10.1259/bjr.20220378] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Revised: 08/01/2022] [Accepted: 08/19/2022] [Indexed: 01/13/2023] Open
Abstract
OBJECTIVES To assess whether virtual non-contrast (VNC) computed tomography (CT) images acquired from dual-energy CT (DECT) have sufficient image quality to replace true non-contrast (TNC) CT images in CT angiography (CTAG). METHODS This study enrolled 63 consecutive patients who underwent a CTAG that included a single-energy non-contrast scan, followed by a post-contrast DECT scan. Comparison of attenuation and noise between TNC and VNC images was made by drawing circular regions of interest (ROI) on a picture archiving and communication system (PACS) workstation within the aortic lumen at the levels of the renal arteries, the aortic bifurcation and right femoral artery. Mean attenuation and image noise (one standard deviation) were registered in Hounsfield units (HU). The VNC images were subjectively evaluated for artifacts such as subtraction of calcifications or architectural distortion based on TNC image as a standard of reference. RESULTS Most attenuations of the VNCs were higher than TNC, except right femoral artery of reader 2. Most image noises of TNC were higher than VNC, except abdominal aorta in reader 1. In qualitative image analysis, mean scores of VNC according to the 5-point scale were 3.68 and 3.63 (reader 1 and reader 2, respectively) which mean good to excellent to diagnose. CONCLUSION HUs and VNC image noises are different from TNC images in CTAG. VNC images have sufficient image quality to replace TNC images in the diagnosis of calcific lesions. ADVANCES IN KNOWLEDGE VNC images acquired from DECT have image quality adequate to replace TNC images in the diagnosis of the calcific lesion on the CTAG. VNC images based on DECT can avoid excessive and unnecessary patient exposure to radiation during CTAG.
Collapse
Affiliation(s)
- Min Hee Lee
- Department of Radiology, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Hee Jin Park
- Department of Radiology, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Ji Na Kim
- Department of Radiology, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Myung Sub Kim
- Department of Radiology, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Seok Woo Hong
- Department of Orthopaedic Surgery, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Jai Hyung Park
- Department of Orthopaedic Surgery, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Chang Ho Kang
- Department of Radiology, Korea University Anam Hospital, Seoul, Korea
| |
Collapse
|
4
|
Takane Y, Sato K, Kageyama R, Takano H, Kayano S. Accuracy of virtual non-contrast images with different algorithms in dual-energy computed tomography. Radiol Phys Technol 2022; 15:234-244. [PMID: 35925476 DOI: 10.1007/s12194-022-00668-0] [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] [Received: 12/13/2021] [Revised: 07/21/2022] [Accepted: 07/22/2022] [Indexed: 11/27/2022]
Abstract
We investigated the accuracy of the computed tomography (CT) numbers of virtual non-contrast (VNC) images for two different material decomposition algorithms using the same image data for different diluted contrast agent concentrations. A container filled with contrast agents was inserted into a cylindrical phantom and scanned with dual-energy protocols (80/Sn140 kV, 100/Sn140 kV) using a dual-source CT. VNC images were generated by the 2-material decomposition (MD) algorithm using the energy of each tube voltage and the linear attenuation coefficient, calculated from the theoretical spectral curve of the agent and the CT number of the image, respectively. Furthermore, VNC images using 3-material decomposition (3-MD) algorithm were produced by applying LiverVNC, an analysis parameter implemented in the scanner. The robustness of both the algorithms was verified by investigating the CT numbers of the agents in the VNC. The closer the CT number is to 0 HU, the more robust the algorithm. Without beam-hardening correction, the CT numbers increased with an increase in concentration in both the algorithms, maximal at 50 mg/ml concentration, with CT numbers of 38 HU for 2-MD, 86 HU for 3-MD. With correction, CT numbers were ± 10 HU or less for both the algorithms up to 30 mg/ml concentration, whereas, for concentrations above 40 mg/ml, the maximal averaged CT number was 12 HU for 2-MD, 22 HU for 3-MD. For both the algorithms, the accuracy of the CT numbers was maintained in the low-concentration range; parameter adjustment was necessary to maintain the accuracy at concentrations higher than clinically expected.
Collapse
Affiliation(s)
- Yumi Takane
- Tohoku University Hospital, 1-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi, 980-8574, Japan.
| | - Kazuhiro Sato
- Tohoku University Graduate School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi, 980-8575, Japan
| | - Ryota Kageyama
- Tohoku University Graduate School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi, 980-8575, Japan
| | - Hirokazu Takano
- Tohoku University Hospital, 1-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi, 980-8574, Japan
| | - Shingo Kayano
- Tohoku University Hospital, 1-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi, 980-8574, Japan
| |
Collapse
|
5
|
Wu MY, Bang TJ, Restauri N, Chawla A, Khawaja RDA, Vargas D. Imaging Acute Aortic Syndromes. Semin Roentgenol 2022; 57:335-344. [DOI: 10.1053/j.ro.2022.07.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2022] [Revised: 07/19/2022] [Accepted: 07/21/2022] [Indexed: 11/11/2022]
|
6
|
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.
Collapse
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
| |
Collapse
|
7
|
Ko JP, Goldstein JM, Latson LA, Azour L, Gozansky EK, Moore W, Patel S, Hutchinson B. Chest CT Angiography for Acute Aortic Pathologic Conditions: Pearls and Pitfalls. Radiographics 2021; 41:399-424. [PMID: 33646903 DOI: 10.1148/rg.2021200055] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Chest CT angiography (CTA) is essential in the diagnosis of acute aortic syndromes. Chest CTA quality can be optimized with attention to technical parameters pertaining to noncontrast imaging, timing of contrast-enhanced imaging, contrast material volume, kilovolt potential, tube-current modulation, and decisions regarding electrocardiographic-gating and ultra-fast imaging, which may affect the accurate diagnosis of acute aortic syndromes. An understanding of methods to apply to address suboptimal image quality is useful, as the accurate identification of acute aortic syndromes is essential for appropriate patient management. Acute aortic syndromes have high morbidity and mortality, particularly when involving the ascending aorta, and include classic aortic dissection, penetrating atherosclerotic ulcer, and acute intramural hematoma. An understanding of the pathogenesis and distinguishing imaging features of acute aortic syndromes and aortic rupture and some less common manifestations is helpful when interpreting imaging examinations. Related entities, such as ulcerated plaque, ulcerlike projections, and intramural blood pools, and mimics, such as vasculitis and aortic thrombus, are important to recognize; knowledge of these is important to avoid interpretive pitfalls. In addition, an awareness of postsurgical aortic changes can be useful when interpreting CTA examinations when patient history is incomplete. The authors review technical considerations when performing CTA, discuss acute aortic syndromes, and highlight diagnostic challenges encountered when interpreting aortic CTA examinations. ©RSNA, 2021.
Collapse
Affiliation(s)
- Jane P Ko
- From the Department of Radiology, NYU Langone Health, 660 First Ave, Room 747, New York, NY 10016 (J.P.K., J.M.G., L.A.L., L.A., E.K.G., W.M.); Department of Radiology, University of Michigan Health System, Ann Arbor, Mich (S.P.); and Department of Radiology, Mater Misericordiae University Hospital, Dublin, Ireland (B.H.)
| | - Jonathan M Goldstein
- From the Department of Radiology, NYU Langone Health, 660 First Ave, Room 747, New York, NY 10016 (J.P.K., J.M.G., L.A.L., L.A., E.K.G., W.M.); Department of Radiology, University of Michigan Health System, Ann Arbor, Mich (S.P.); and Department of Radiology, Mater Misericordiae University Hospital, Dublin, Ireland (B.H.)
| | - Larry A Latson
- From the Department of Radiology, NYU Langone Health, 660 First Ave, Room 747, New York, NY 10016 (J.P.K., J.M.G., L.A.L., L.A., E.K.G., W.M.); Department of Radiology, University of Michigan Health System, Ann Arbor, Mich (S.P.); and Department of Radiology, Mater Misericordiae University Hospital, Dublin, Ireland (B.H.)
| | - Lea Azour
- From the Department of Radiology, NYU Langone Health, 660 First Ave, Room 747, New York, NY 10016 (J.P.K., J.M.G., L.A.L., L.A., E.K.G., W.M.); Department of Radiology, University of Michigan Health System, Ann Arbor, Mich (S.P.); and Department of Radiology, Mater Misericordiae University Hospital, Dublin, Ireland (B.H.)
| | - Elliott K Gozansky
- From the Department of Radiology, NYU Langone Health, 660 First Ave, Room 747, New York, NY 10016 (J.P.K., J.M.G., L.A.L., L.A., E.K.G., W.M.); Department of Radiology, University of Michigan Health System, Ann Arbor, Mich (S.P.); and Department of Radiology, Mater Misericordiae University Hospital, Dublin, Ireland (B.H.)
| | - William Moore
- From the Department of Radiology, NYU Langone Health, 660 First Ave, Room 747, New York, NY 10016 (J.P.K., J.M.G., L.A.L., L.A., E.K.G., W.M.); Department of Radiology, University of Michigan Health System, Ann Arbor, Mich (S.P.); and Department of Radiology, Mater Misericordiae University Hospital, Dublin, Ireland (B.H.)
| | - Smita Patel
- From the Department of Radiology, NYU Langone Health, 660 First Ave, Room 747, New York, NY 10016 (J.P.K., J.M.G., L.A.L., L.A., E.K.G., W.M.); Department of Radiology, University of Michigan Health System, Ann Arbor, Mich (S.P.); and Department of Radiology, Mater Misericordiae University Hospital, Dublin, Ireland (B.H.)
| | - Barry Hutchinson
- From the Department of Radiology, NYU Langone Health, 660 First Ave, Room 747, New York, NY 10016 (J.P.K., J.M.G., L.A.L., L.A., E.K.G., W.M.); Department of Radiology, University of Michigan Health System, Ann Arbor, Mich (S.P.); and Department of Radiology, Mater Misericordiae University Hospital, Dublin, Ireland (B.H.)
| |
Collapse
|
8
|
Patel VK, Fruauff A, Esses D, Lipsitz EC, Levsky JM, Haramati LB. Implementation of an aortic dissection CT protocol with clinical decision support aimed at decreasing radiation exposure by reducing routine abdominopelvic imaging. Clin Imaging 2020; 67:108-112. [PMID: 32559680 DOI: 10.1016/j.clinimag.2020.06.005] [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: 03/06/2020] [Revised: 05/19/2020] [Accepted: 06/01/2020] [Indexed: 10/24/2022]
Abstract
Patients suspected of having an acute aortic syndrome in the ED typically undergo CT of the chest/abdomen/pelvis. However, the overwhelming majority of these exams are negative. With the help of clinical decision support, we implemented a new radiologist monitored 'aortic dissection screening protocol' that forgoes routine abdominopelvic imaging in order to reduce radiation dose without compromising diagnostic accuracy. The purpose of the present study is to assess the performance of this protocol. A retrospective analysis was performed to study the effect of the dissection screening protocol on the diagnostic yield, radiation and contrast dose on a total of 835 ED patients who underwent CT scans for suspected aortic dissection over a 48-week study period immediately before and after implementation of the protocol. 3.4% (28/835) of examinations were positive for an acute aortic syndrome over the 48-week study period with no difference in positivity before and after implementation of the 'aortic dissection screening' protocol, 3.0% vs. 3.7%, respectively (p = 0.57). There was a 14.6% reduction in median radiation dose and a 16% decrease in contrast volume utilization for the total ED population who underwent CT for aortic dissection using any protocol in the period after implementation of the 'aortic dissection screening' protocol. Aortic dissection CT in the ED is negative in the overwhelming majority of cases. A monitored 'aortic dissection screening' protocol that initially images the chest only significantly reduced contrast and radiation dose without reducing diagnostic accuracy for ED patients who underwent CT for aortic dissection.
Collapse
Affiliation(s)
- Vishal K Patel
- Department of Radiology, Montefiore Medical Center, Bronx, NY 10467, United States; Albert Einstein College of Medicine, Bronx, NY 10467, United States.
| | - Alana Fruauff
- Albert Einstein College of Medicine, Bronx, NY 10467, United States
| | - David Esses
- Albert Einstein College of Medicine, Bronx, NY 10467, United States; Department of Emergency Medicine, Montefiore Medical Center, Bronx, NY 10467, United States
| | - Evan C Lipsitz
- Albert Einstein College of Medicine, Bronx, NY 10467, United States; Division of Vascular and Endovascular Surgery, Department of Cardiothoracic and Vascular Surgery, Montefiore Medical Center, Bronx, NY 10467, United States
| | - Jeffrey M Levsky
- Department of Radiology, Montefiore Medical Center, Bronx, NY 10467, United States; Albert Einstein College of Medicine, Bronx, NY 10467, United States; Department of Medicine, Montefiore Medical Center, Bronx, NY 10467, United States
| | - Linda B Haramati
- Department of Radiology, Montefiore Medical Center, Bronx, NY 10467, United States; Albert Einstein College of Medicine, Bronx, NY 10467, United States; Department of Medicine, Montefiore Medical Center, Bronx, NY 10467, United States
| |
Collapse
|
9
|
Lehti L, Söderberg M, Höglund P, Wassélius J. Comparing Arterial- and Venous-Phase Acquisition for Optimization of Virtual Noncontrast Images From Dual-Energy Computed Tomography Angiography. J Comput Assist Tomogr 2019; 43:770-774. [PMID: 31425308 PMCID: PMC6752687 DOI: 10.1097/rct.0000000000000903] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Follow-up with computed tomographic angiography is recommended after endovascular aneurysm repair, exposing patients to significant levels of radiation and iodine contrast medium. Dual-energy computed tomography allows virtual noncontrast (VNC) images to be reconstructed from contrast-enhanced images using a software algorithm. If the VNC images are a good-enough approximation of true noncontrast (TNC) images, a reduction in radiation dose can be ensured through omitting a TNC scan.
Collapse
Affiliation(s)
- Leena Lehti
- From the Department of Clinical Sciences, Lund University, Lund.,Vascular Center, Skåne University Hospital
| | - Marcus Söderberg
- Department of Translational Medicine, Medical Radiation Physics, Lund University.,Radiation Physics, Department of Hematology, Oncology and Radiation Physics, Skåne University Hospital, Malmö
| | - Peter Höglund
- From the Department of Clinical Sciences, Lund University, Lund
| | - Johan Wassélius
- From the Department of Clinical Sciences, Lund University, Lund.,Department of Neuroradiology, Skåne University Hospital, Lund, Sweden
| |
Collapse
|
10
|
Interscanner and Intrascanner Comparison of Virtual Unenhanced Attenuation Values Derived From Twin Beam Dual-Energy and Dual-Source, Dual-Energy Computed Tomography. Invest Radiol 2019; 54:1-6. [PMID: 30096063 DOI: 10.1097/rli.0000000000000501] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE The aim of the current study was to evaluate the reliability and comparability of virtual unenhanced (VUE) attenuation values derived from scans of a single-source, dual-energy computed tomography using a split-filter (tbDECT) to a dual-source dual-energy CT (dsDECT). MATERIALS AND METHODS In this retrospective study, comparisons for tbDECT and dsDECT were made within and between different dual-energy platforms. For the interscanner comparison, 126 patients were scanned with both scanners within a time interval of 224 ± 180 days; for the intrascanner comparison, another 90 patients were scanned twice with the same scanner within a time interval of 136 ± 140 days. Virtual unenhanced images were processed off of venous phase series. Attenuation values of 7 different tissues were recorded. Disagreement for VUE HU measurements greater than 10 HU between 2 scans was defined as inadequate. RESULTS The interscanner analysis showed significant difference between tbDE and dsDE VUE CT values (P < 0.01) for 6 of 7 organs. Percentage of cases that had more than 10 HU difference between tbDE and dsDE for an individual patient ranged between 15% (left kidney) and 62% (spleen).The intrascanner analysis showed no significant difference between repeat scans for both tbDECT and dsDECT (P > 0.05). However, intrascanner disagreements for the VUE HU measurements greater than 10 HU were recorded in 10% of patients scanned on the tbDECT and 0% of patients scanned on the dsDECT. The organs with the highest portion of greater than 10 HU errors were the liver and the aorta (both 20%). CONCLUSIONS Dual-energy techniques vary in reproducibility of VUE attenuation values. In the current study, tbDECT demonstrated higher variation in VUE HU measurements in comparison to a dsDECT. Virtual unenhanced HU measurements cannot be reliably compared on follow-up CT, if these 2 different dual-energy CT platforms are used.
Collapse
|
11
|
Lehti L, Söderberg M, Höglund P, Nyman U, Gottsäter A, Wassélius J. Reliability of virtual non-contrast computed tomography angiography: comparing it with the real deal. Acta Radiol Open 2018; 7:2058460118790115. [PMID: 30181911 PMCID: PMC6114525 DOI: 10.1177/2058460118790115] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2018] [Accepted: 06/28/2018] [Indexed: 11/15/2022] Open
Abstract
Background Computed tomographic angiography (CTA) may require a non-contrast enhanced
dataset for the diagnostic workup. By using dual-energy acquisition, it is
possible to obtain a virtual non-contrast-enhanced (VNC) dataset, thereby
possibly eliminating the non-contrast acquisition and reducing the radiation
dose. Purpose To compare image quality of VNC images reconstructed from arterial phase
dual-energy CTA to true non-contrast (TNC) images, and to assess whether VNC
images were of sufficient quality to replace TNC images. Material and methods Thirty consecutive patients with suspected abdominal aortic aneurysm, aortic
dissection, or subacute control after EVAR/TEVAR were examined with
dual-energy CT (DECT). The examination protocol included a single-energy
TNC, DECT arterial phase (80 kV/Sn140 kV), and single-energy in venous phase
of the aorta. A VNC dataset was obtained from the DE acquisition from
arterial phase scans. Mean attenuation and image noise were measured within
regions of interest at three levels in the aorta in TNC and VNC images.
Comparison of the TNC and VNC images for artefacts was made side-by-side.
Subjective evaluation included overall image quality on a 4-grade scale, and
quantitative analysis of algorithm-induced artefacts by two experienced
readers. Results For all cases, the aortic attenuation was significantly higher at VNC than at
TNC. Image noise measured quantitatively was also significantly higher at
VNC than at TNC. Subjective image quality was lower for VNC (mean = 3.1 for
VNC, 3.7 = for TNC) but there were no cases rated non-diagnostic. Conclusion VNC images based on arterial phase CTA have significantly higher mean
attenuation and higher noise levels compared to TNC.
Collapse
Affiliation(s)
- Leena Lehti
- Department of Clinical Sciences, Lund
University, Lund, Sweden
- Vascular Center, Skåne University
Hospital, Malmö, Sweden
- Leena Lehti, Vascular Center, Skåne
University Hospital, 20502 Malmö, Sweden.
| | - Marcus Söderberg
- Department of Translational Medicine,
Medical Radiation Physics, Lund University, Malmö, Sweden
| | - Peter Höglund
- Department of Clinical Sciences, Lund
University, Lund, Sweden
| | - Ulf Nyman
- Department of Translational Medicine,
Division of Medical Radiology, Lund University, Malmö, Sweden
| | - Anders Gottsäter
- Department of Clinical Sciences, Lund
University, Lund, Sweden
- Vascular Center, Skåne University
Hospital, Malmö, Sweden
| | - Johan Wassélius
- Department of Clinical Sciences, Lund
University, Lund, Sweden
- Department of Neuroradiology, Skåne
University Hospital, Lund, Sweden
| |
Collapse
|
12
|
Partovi S, Trischman T, Rafailidis V, Ganguli S, Rengier F, Goerne H, Rajiah P, Staub D, Patel IJ, Oliveira G, Ghoshhajra B. Multimodality imaging assessment of endoleaks post-endovascular aortic repair. Br J Radiol 2018; 91:20180013. [PMID: 29658769 DOI: 10.1259/bjr.20180013] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Endoleaks are a common complication of endovascular aortic repair (EVAR). As a result, patients require lifelong imaging surveillance following EVAR. In current clinical practice, evaluation for endoleaks is predominantly performed with CT angiography (CTA). Due to the significant cumulative radiation burden associated with repetitive CTA imaging, as well as the repeated administration of nephrotoxic contrast agent, contrast-enhanced ultrasound (CEUS) and magnetic resonance angiography (MRA) have evolved as potential modalities for lifelong surveillance post-EVAR. In this paper, multimodality imaging, including CTA, CEUS and MRA, for the surveillance of endoleaks is discussed. Further, new CTA techniques for radiation reduction are elaborated. Additionally, imagery for three cases of aortic endoleak detection using CTA and five cases using MRA are presented. Imaging for different types of endoleaks with CTA, MRA and CEUS are presented. For lifelong endoleak surveillance post-EVAR, CTA is still regarded as the imaging modality of choice. However, advancements in CEUS and MRA technique enable partial replacement of CTA in certain patients.
Collapse
Affiliation(s)
- Sasan Partovi
- 1 Department of Radiology, Section of Vascular and Interventional Radiology, University Hospitals Cleveland Medical Center, Case Western Reserve University , Cleveland, OH , USA
| | - Thomas Trischman
- 1 Department of Radiology, Section of Vascular and Interventional Radiology, University Hospitals Cleveland Medical Center, Case Western Reserve University , Cleveland, OH , USA
| | - Vasileios Rafailidis
- 2 Department of Radiology, AHEPA University General Hospital, Aristotle University of Thessaloniki , Thessaloniki , Greece
| | - Suvranu Ganguli
- 3 Department of Radiology, Division of Cardiovascular Imaging, Massachusetts General Hospital, Harvard Medical School , Boston, MA , USA
| | - Fabian Rengier
- 4 Department of Diagnostic and Interventional Radiology, University Hospital Heidelberg , Heidelberg , Germany
| | - Harold Goerne
- 5 Department of Radiology, Division of Cardiothoracic Imaging, UT Southwestern Medical Center , Dallas, TX , USA
| | - Prabhakar Rajiah
- 5 Department of Radiology, Division of Cardiothoracic Imaging, UT Southwestern Medical Center , Dallas, TX , USA
| | - Daniel Staub
- 6 Department of Vascular Medicine, University Hospital Basel, University of Basel , Basel , Switzerland
| | - Indravadan J Patel
- 1 Department of Radiology, Section of Vascular and Interventional Radiology, University Hospitals Cleveland Medical Center, Case Western Reserve University , Cleveland, OH , USA
| | - George Oliveira
- 3 Department of Radiology, Division of Cardiovascular Imaging, Massachusetts General Hospital, Harvard Medical School , Boston, MA , USA
| | - Brian Ghoshhajra
- 3 Department of Radiology, Division of Cardiovascular Imaging, Massachusetts General Hospital, Harvard Medical School , Boston, MA , USA
| |
Collapse
|
13
|
Punjabi GV. Multi-energy spectral CT: adding value in emergency body imaging. Emerg Radiol 2017; 25:197-204. [PMID: 29185082 DOI: 10.1007/s10140-017-1569-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Accepted: 11/20/2017] [Indexed: 12/21/2022]
Abstract
Most vendors offer scanners capable of dual- or multi-energy computed tomography (CT) imaging. Advantages of multi-energy CT scanning include superior tissue characterization, detection of subtle iodine uptake differences, and opportunities to reduce contrast dose. However, utilization of this technology in the emergency department (ED) remains low. The purpose of this pictorial essay is to illustrate the value of multi-energy CT scanning in emergency body imaging.
Collapse
Affiliation(s)
- Gopal V Punjabi
- Hennepin County Medical Center, 701, Park Ave, Minneapolis, MN, 55455, USA.
| |
Collapse
|
14
|
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]
|
15
|
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.
Collapse
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
| |
Collapse
|
16
|
Halliburton SS, Rajiah P. Cardiac CT Scanner Technology: What Is New and What Is Next? CURRENT CARDIOVASCULAR IMAGING REPORTS 2016. [DOI: 10.1007/s12410-016-9370-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
|
17
|
Rajiah P, Halliburton SS. Dual Energy Imaging in Cardiovascular CT: Current Status and Impact on Radiation, Contrast and Accuracy. CURRENT CARDIOVASCULAR IMAGING REPORTS 2014. [DOI: 10.1007/s12410-014-9289-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
|
18
|
Yang Y, Jia X, Deng Y, Chen J, Zhang LJ. Can virtual non-enhanced CT be used to replace true non-enhanced CT for the detection of palpable cervical lymph nodes? A preliminary study. Jpn J Radiol 2014; 32:324-30. [DOI: 10.1007/s11604-014-0308-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2013] [Accepted: 03/04/2014] [Indexed: 10/25/2022]
|
19
|
Wrangle J, Wang W, Koch A, Easwaran H, Mohammad HP, Vendetti F, VanCriekinge W, DeMeyer T, Du Z, Parsana P, Rodgers K, Yen RW, Zahnow CA, Taube JM, Brahmer JR, Tykodi SS, Easton K, Carvajal RD, Jones PA, Laird PW, Weisenberger DJ, Tsai S, Juergens RA, Topalian SL, Rudin CM, Brock MV, Pardoll D, Baylin SB. Alterations of immune response of Non-Small Cell Lung Cancer with Azacytidine. Oncotarget 2013; 4:2067-79. [PMID: 24162015 PMCID: PMC3875770 DOI: 10.18632/oncotarget.1542] [Citation(s) in RCA: 293] [Impact Index Per Article: 26.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2013] [Accepted: 10/25/2013] [Indexed: 12/14/2022] Open
Abstract
Innovative therapies are needed for advanced Non-Small Cell Lung Cancer (NSCLC). We have undertaken a genomics based, hypothesis driving, approach to query an emerging potential that epigenetic therapy may sensitize to immune checkpoint therapy targeting PD-L1/PD-1 interaction. NSCLC cell lines were treated with the DNA hypomethylating agent azacytidine (AZA - Vidaza) and genes and pathways altered were mapped by genome-wide expression and DNA methylation analyses. AZA-induced pathways were analyzed in The Cancer Genome Atlas (TCGA) project by mapping the derived gene signatures in hundreds of lung adeno (LUAD) and squamous cell carcinoma (LUSC) samples. AZA up-regulates genes and pathways related to both innate and adaptive immunity and genes related to immune evasion in a several NSCLC lines. DNA hypermethylation and low expression of IRF7, an interferon transcription factor, tracks with this signature particularly in LUSC. In concert with these events, AZA up-regulates PD-L1 transcripts and protein, a key ligand-mediator of immune tolerance. Analysis of TCGA samples demonstrates that a significant proportion of primary NSCLC have low expression of AZA-induced immune genes, including PD-L1. We hypothesize that epigenetic therapy combined with blockade of immune checkpoints - in particular the PD-1/PD-L1 pathway - may augment response of NSCLC by shifting the balance between immune activation and immune inhibition, particularly in a subset of NSCLC with low expression of these pathways. Our studies define a biomarker strategy for response in a recently initiated trial to examine the potential of epigenetic therapy to sensitize patients with NSCLC to PD-1 immune checkpoint blockade.
Collapse
Affiliation(s)
- John Wrangle
- The Johns Hopkins University, School of Medicine, Oncology Center-Hematology/Medical Oncology, Baltimore, Maryland
| | - Wei Wang
- The Johns Hopkins University, School of Medicine, Human Genetics Graduate Program, Baltimore, Maryland
| | - Alexander Koch
- Departments of Molecular Biotechnology, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium
| | - Hariharan Easwaran
- The Johns Hopkins University, School of Medicine, Oncology, Baltimore, Maryland
| | - Helai P. Mohammad
- GlaxoSmithKline Pharmaceuticals, Cancer Epigenetics and Oncology, Collegeville, Pennsylvania
| | - Frank Vendetti
- The Johns Hopkins University, School of Medicine, Oncology, Baltimore, Maryland
| | - Wim VanCriekinge
- Departments of Molecular Biotechnology, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium
| | - Tim DeMeyer
- Departments of Molecular Biotechnology, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium
| | - Zhengzong Du
- The Johns Hopkins University, School of Medicine, Oncology, Baltimore, Maryland
| | - Princy Parsana
- The Johns Hopkins University, Advanced Academic Bioinformatics, Baltimore, Maryland
| | - Kristen Rodgers
- The Johns Hopkins University, School of Medicine, Oncology, Baltimore, Maryland
| | - Ray-Whay Yen
- The Johns Hopkins University, School of Medicine, Oncology, Baltimore, Maryland
| | - Cynthia A. Zahnow
- The Johns Hopkins University, School of Medicine, Oncology, Baltimore, Maryland
| | - Janis M. Taube
- The Johns Hopkins University, School of Medicine, Dermatology and Oral Pathology, Baltimore, Maryland
| | - Julie R. Brahmer
- The Johns Hopkins University, School of Medicine, Oncology, Baltimore, Maryland
| | - Scott S. Tykodi
- University of Washington and Fred Hutchison Cancer Research Center, Seattle Cancer Care Alliance, Seattle, Washington
| | - Keith Easton
- University of Washington and Fred Hutchison Cancer Research Center, Seattle Cancer Care Alliance, Seattle, Washington
| | | | - Peter A. Jones
- USC Epigenome Center, Keck School of Medicine, University of Southern California, Los Angeles, California
| | - Peter W. Laird
- USC Epigenome Center, Keck School of Medicine, University of Southern California, Los Angeles, California
| | - Daniel J. Weisenberger
- USC Epigenome Center, Keck School of Medicine, University of Southern California, Los Angeles, California
| | - Salina Tsai
- The Johns Hopkins University, School of Medicine, Russell H. Morgan Department of Radiology and Radiological Science, Baltimore, Maryland
| | - Rosalyn A. Juergens
- The Johns Hopkins University, School of Medicine, Oncology, Baltimore, Maryland
| | - Suzanne L. Topalian
- The Johns Hopkins University, School of Medicine, Surgery, Baltimore, Maryland
| | - Charles M. Rudin
- The Johns Hopkins University, School of Medicine, Oncology, Baltimore, Maryland
| | - Malcolm V. Brock
- The Johns Hopkins University, School of Medicine, Oncology, Baltimore, Maryland
| | - Drew Pardoll
- The Johns Hopkins University, School of Medicine, Oncology, Baltimore, Maryland
| | - Stephen B. Baylin
- The Johns Hopkins University, School of Medicine, Oncology, Baltimore, Maryland
| |
Collapse
|
20
|
Kaufmann S, Sauter A, Spira D, Gatidis S, Ketelsen D, Heuschmid M, Claussen CD, Thomas C. Tin-filter enhanced dual-energy-CT: image quality and accuracy of CT numbers in virtual noncontrast imaging. Acad Radiol 2013; 20:596-603. [PMID: 23490736 DOI: 10.1016/j.acra.2013.01.010] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2012] [Revised: 01/08/2013] [Accepted: 01/09/2013] [Indexed: 11/30/2022]
Abstract
OBJECTIVES To measure and compare the objective image quality of true noncontrast (TNC) images with virtual noncontrast (VNC) images acquired by tin-filter-enhanced, dual-source, dual-energy computed tomography (DECT) of upper abdomen. MATERIALS AND METHODS Sixty-three patients received unenhanced abdominal CT and enhanced abdominal DECT (100/140 kV with tin filter) in portal-venous phase. VNC images were calculated from the DECT datasets using commercially available software. The mean attenuation of relevant tissues and image quality were compared between the TNC and VNC images. Image quality was rated objectively by measuring image noise and the sharpness of object edges using custom-designed software. Measurements were compared using Student two-tailed t-test. Correlation coefficients for tissue attenuation measurements between TNC and VNC were calculated and the relative deviations were illustrated using Bland-Altman plots. RESULTS Mean attenuation differences between TNC and VNC (HUTNC - HUVNC) image sets were as follows: right liver lobe -4.94 Hounsfield units (HU), left liver lobe -3.29 HU, vena cava -2.19 HU, spleen -7.46 HU, pancreas 1.29 HU, fat -11.14 HU, aorta 1.29 HU, bone marrow 36.83 HU (all P < .05); right kidney 0.46 HU, left kidney 0.56 HU, vena portae -0.48 HU and muscle -0.62 HU (nonsignificant). Good correlations between VNC and TNC series were observed for liver, vena portae, kidneys, pancreas, muscle and bone marrow (Pearson's correlation coefficient ≥0.75). Mean image noise was significantly higher in TNC images (P < .0001). Measurements of edge sharpness revealed no significant differences between VNC and TNC images (P = .19). CONCLUSION The Hounsfield units in VNC images closely resemble TNC images in the majority of the organs of the upper abdomen (kidneys, liver, pancreas). In spleen and fat, Hounsfield numbers in VNC images are tend to be higher than in TNC images. VNC images show a low image noise and satisfactory edge sharpness. Other criteria of image quality and the depiction of certain lesions need to be evaluated additionally.
Collapse
Affiliation(s)
- Sascha Kaufmann
- Department of Radiology, Diagnostic and Interventional Radiology, Hoppe-Seyler-Str. 3, 72076 Tuebingen, Germany.
| | | | | | | | | | | | | | | |
Collapse
|
21
|
Abstract
OBJECTIVE Various applications for dual-energy CT (DECT) have been investigated and have shown substantial clinical benefits. However, only limited data are available regarding the radiation dose associated with DECT imaging. The purpose of this article is to review the available literature regarding the radiation dose associated with DECT imaging applications in comparison with conventional single-energy CT techniques. CONCLUSION The rediscovery of DECT and the increasing availability of this technique on clinical CT systems have opened new dimensions for CT. The advanced spectral differentiation of materials within the human body as well as the selective visualization or subtraction of iodinated contrast material or xenon provides both advanced visualization of disease-specific molecular substrates as well as additional functional information within a single scan.
Collapse
|