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Jepson BM, Rigsby CK, Hlavacek AM, Prakash A, Priya S, Barfuss S, Chelliah A, Binka E, Nicol E, Ghoshhajra B, Han BK. Proposed competencies for the performance of cardiovascular computed tomography in pediatric and adult congenital heart disease. J Cardiovasc Comput Tomogr 2023; 17:295-301. [PMID: 37625911 DOI: 10.1016/j.jcct.2023.08.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Revised: 07/25/2023] [Accepted: 08/04/2023] [Indexed: 08/27/2023]
Abstract
Cardiovascular computed tomography (CCT) is rated appropriate by published guidelines for the initial evaluation and follow up of congenital heart disease (CHD) and is an essential modality in cardiac imaging programs for patients of all ages. However, no recommended core competencies exist to guide CCT in CHD imaging training pathways, curricula development, or establishment of a more formal educational platform. To fill this gap, a group of experienced congenital cardiac imagers, intentionally inclusive of adult and pediatric cardiologists and radiologists, was formed to propose core competencies fundamental to the expert-level performance of CCT in pediatric acquired and congenital heart disease and adult CHD. The 2020 SCCT Guideline for Training Cardiology and Radiology Trainees as Independent Practitioners (Level II) and Advanced Practitioners (Level III) in Cardiovascular Computed Tomography (1) for adult imaging were used as a framework to define pediatric and CHD-specific competencies. Established competencies will be immediately relevant for advanced cardiac imaging fellowships in both cardiology and radiology training pathways. Proposed future steps include radiology and cardiology society collaboration to establish provider certification levels, training case-volume recommendations, and continuing medical education (CME) requirements for expert-level performance of CCT in pediatric and adult CHD.
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Affiliation(s)
- Bryan M Jepson
- University of Utah, Intermountain Primary Children's Hospital, Salt Lake City, UT, USA
| | - Cynthia K Rigsby
- Ann & Robert H Lurie Children's Hospital of Chicago, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - Anthony M Hlavacek
- Shawn Jenkins Children's Hospital, Department of Pediatrics, Division of Pediatric Cardiology, Medical University of South Carolina, Charleston, SC, USA
| | - Ashwin Prakash
- Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Sarv Priya
- University of Iowa Hospitals & Clinics, Carver College of Medicine, Iowa City, IA, USA
| | - Spencer Barfuss
- Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Anjali Chelliah
- Division of Pediatric Cardiology, Goryeb Children's Hospital, Atlantic Health System, Morristown, NJ and Division of Pediatric Cardiology, Columbia University Irving Medical Center, New York, NY, USA
| | - Edem Binka
- University of Utah, Intermountain Primary Children's Hospital, Salt Lake City, UT, USA
| | - Edward Nicol
- Royal Brompton and Harefield Hospitals, Imperial College of London School of Medicine, UK; School of Biomedical Engineering and Imaging Sciences, King's College, London, UK
| | - Brian Ghoshhajra
- Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - B Kelly Han
- University of Utah, Intermountain Primary Children's Hospital, Salt Lake City, UT, USA.
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Diagnostic Validity and Reliability of Low-Dose Prospective ECG-Triggering Cardiac CT in Preoperative Assessment of Complex Congenital Heart Diseases (CHDs). CHILDREN (BASEL, SWITZERLAND) 2022; 9:children9121903. [PMID: 36553346 PMCID: PMC9776829 DOI: 10.3390/children9121903] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Revised: 12/01/2022] [Accepted: 12/02/2022] [Indexed: 12/12/2022]
Abstract
For the precise preoperative evaluation of complex congenital heart diseases (CHDs) with reduced radiation dose exposure, we assessed the diagnostic validity and reliability of low-dose prospective ECG-gated cardiac CT (CCT). Forty-two individuals with complex CHDs who underwent preoperative CCT as part of a prospective study were included. Each CCT image was examined independently by two radiologists. The primary reference for assessing the diagnostic validity of the CCT was the post-operative data. Infants and neonates were the most common age group suffering from complex CHDs. The mean volume of the CT dose index was 1.44 ± 0.47 mGy, the mean value of the dose-length product was 14.13 ± 5.4 mGy*cm, and the mean value of the effective radiation dose was 0.58 ± 0.13 mSv. The sensitivity, specificity, PPV, NPV, and accuracy of the low-dose prospective ECG-gated CCT for identifying complex CHDs were 95.6%, 98%, 97%, 97%, and 97% for reader 1 and 92.6%, 97%, 95.5%, 95.1%, and 95.2% for reader 2, respectively. The overall inter-reader agreement for interpreting the cardiac CCTs was good (κ = 0.74). According to the results of our investigation, low-dose prospective ECG-gated CCT is a useful and trustworthy method for assessing coronary arteries and making a precise preoperative diagnosis of complex CHDs.
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Takagi H, Leipsic JA, Indraratna P, Gulsin G, Khasanova E, Tzimas G, Lin FY, Shaw LJ, Lee SE, Andreini D, Al-Mallah MH, Budoff MJ, Cademartiri F, Chinnaiyan K, Choi JH, Conte E, Marques H, de Araújo Gonçalves P, Gottlieb I, Hadamitzky M, Maffei E, Pontone G, Shin S, Kim YJ, Lee BK, Chun EJ, Sung JM, Virmani R, Samady H, Stone PH, Berman DS, Narula J, Bax JJ, Chang HJ. Association of Tube Voltage With Plaque Composition on Coronary CT Angiography: Results From PARADIGM Registry. JACC Cardiovasc Imaging 2021; 14:2429-2440. [PMID: 34419398 DOI: 10.1016/j.jcmg.2021.07.011] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/22/2021] [Revised: 07/06/2021] [Accepted: 07/08/2021] [Indexed: 11/16/2022]
Abstract
OBJECTIVES This study sought to investigate the impact of low tube voltage scanning heterogeneity of coronary luminal attenuation on plaque quantification and characterization with coronary computed tomography angiography (CCTA). BACKGROUND The impact of low tube voltage and coronary luminal attenuation on quantitative coronary plaque remains uncertain. METHODS A total of 1,236 consecutive patients (age: 60 ± 9 years; 41% female) who underwent serial CCTA at an interval of ≥2 years were included from an international registry. Patients with prior revascularization or nonanalyzable coronary CTAs were excluded. Total coronary plaque volume was assessed and subclassified based on specific Hounsfield unit (HU) threshold: necrotic core, fibrofatty plaque, and fibrous plaque and dense calcium. Luminal attenuation was measured in the aorta. RESULTS With increasing luminal HU (<350, 350-500, and >500 HU), percent calcified plaque was increased (16%, 27%, and 40% in the median; P < 0.001), and fibrofatty plaque (26%, 13%, and 4%; P < 0.001) and necrotic core (1.6%, 0.3%, and 0.0%; P < 0.001) were decreased. Higher tube voltage scanning (80, 100, and 120 kV) resulted in decreasing luminal attenuation (689 ± 135, 497 ± 89, and 391 ± 73 HU; P < 0.001) and calcified plaque volume (59%, 34%, and 23%; P < 0.001) and increased fibrofatty plaque (3%, 9%, and 18%; P < 0.001) and necrotic core (0.2%, 0.1%, and 0.6%; P < 0.001). Mediation analysis showed that the impact of 100 kV on plaque composition, compared with 120 kV, was primarily caused by an indirect effect through blood pool attenuation. Tube voltage scanning of 80 kV maintained a direct effect on fibrofatty plaque and necrotic core in addition to an indirect effect through the luminal attenuation. CONCLUSIONS Low tube voltage usage affected plaque morphology, mainly through an increase in luminal HU with a resultant increase in calcified plaque and a reduction in fibrofatty and necrotic core. These findings should be considered as CCTA-based plaque measures are being used to guide medical management and, in particular, when being used as a measure of treatment response. (Progression of Atherosclerotic Plaque Determined by Computed Tomographic Angiography Imaging [PARADIGM]; NCT02803411).
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Affiliation(s)
- Hidenobu Takagi
- Department of Radiology, St. Paul's Hospital and University of British Columbia, Vancouver, British Columbia, Canada; Department of Diagnostic Radiology, Tohoku University Hospital, Miyagi, Japan
| | - Jonathon A Leipsic
- Department of Radiology, St. Paul's Hospital and University of British Columbia, Vancouver, British Columbia, Canada.
| | - Praveen Indraratna
- Department of Radiology, St. Paul's Hospital and University of British Columbia, Vancouver, British Columbia, Canada
| | - Gaurav Gulsin
- Department of Radiology, St. Paul's Hospital and University of British Columbia, Vancouver, British Columbia, Canada
| | - Elina Khasanova
- Department of Radiology, St. Paul's Hospital and University of British Columbia, Vancouver, British Columbia, Canada
| | - Georgios Tzimas
- Department of Radiology, St. Paul's Hospital and University of British Columbia, Vancouver, British Columbia, Canada
| | - Fay Y Lin
- Dalio Institute of Cardiovascular Imaging, Department of Radiology, NewYork-Presbyterian Hospital and Weill Cornell Medicine, New York, New York, USA
| | - Leslee J Shaw
- Dalio Institute of Cardiovascular Imaging, Department of Radiology, NewYork-Presbyterian Hospital and Weill Cornell Medicine, New York, New York, USA
| | - Sang-Eun Lee
- Division of Cardiology, Department of Internal Medicine, Ewha Womans University Seoul Hospital, Seoul, Korea; Yonsei-Cedars-Sinai Integrative Cardiovascular Imaging Research Center, Yonsei University College of Medicine, Yonsei University Health System, South Korea
| | - Daniele Andreini
- Centro Cardiologico Monzino, Istituto di Ricovero e Cura a Carattere (IRCCS) Milan, Italy
| | - Mouaz H Al-Mallah
- Houston Methodist DeBakey Heart and Vascular Center, Houston Methodist Hospital, Houston, Texas, USA
| | - Matthew J Budoff
- Department of Medicine, Los Angeles Biomedical Research Institute, Torrance, California, USA
| | | | - Kavitha Chinnaiyan
- Department of Cardiology, William Beaumont Hospital, Royal Oak, Mississippi, USA
| | | | - Edoardo Conte
- Centro Cardiologico Monzino, Istituto di Ricovero e Cura a Carattere (IRCCS) Milan, Italy
| | - Hugo Marques
- Unit of Cardiovascular Imaging, Hospital da Luz, Lisboa, Portugal
| | - Pedro de Araújo Gonçalves
- Unit of Cardiovascular Imaging, Hospital da Luz, Lisboa, Portugal; Nova Medical School, Lisboa, Portugal
| | - Ilan Gottlieb
- Department of Radiology, Casa de Saude São Jose, Rio de Janeiro, Brazil
| | - Martin Hadamitzky
- Department of Radiology and Nuclear Medicine, German Heart Center Munich, Munich, Germany
| | - Erica Maffei
- Department of Radiology, Area Vasta 1/Azienda Sanitaria Unica Regionale Marche, Urbino, Italy
| | - Gianluca Pontone
- Centro Cardiologico Monzino, Istituto di Ricovero e Cura a Carattere (IRCCS) Milan, Italy
| | - Sanghoon Shin
- Division of Cardiology, Department of Internal Medicine, Ewha Womans University Seoul Hospital, Seoul, Korea
| | - Yong-Jin Kim
- Department of Internal Medicine, Seoul National University College of Medicine, Cardiovascular Center, Seoul National University Hospital, Seoul, South Korea
| | - Byoung Kwon Lee
- Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, Korea
| | - Eun Ju Chun
- Seoul National University Bundang Hospital, Sungnam, South Korea
| | - Ji Min Sung
- Yonsei-Cedars-Sinai Integrative Cardiovascular Imaging Research Center, Yonsei University College of Medicine, Yonsei University Health System, South Korea; Division of Cardiology, Severance Cardiovascular Hospital, Yonsei University College of Medicine, Yonsei University Health System, Seoul, South Korea
| | - Renu Virmani
- Department of Pathology, CVPath Institute, Gaithersburg, Maryland, USA
| | - Habib Samady
- Division of Cardiology, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Peter H Stone
- Cardiovascular Division, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Daniel S Berman
- Department of Imaging and Medicine, Cedars Sinai Medical Center, Los Angeles, California, USA
| | - Jagat Narula
- Icahn School of Medicine at Mount Sinai, Mount Sinai Heart, Zena and Michael A. Wiener Cardiovascular Institute, and Marie-Josée and Henry R. Kravis Center for Cardiovascular Health, New York, New York, USA
| | - Jeroen J Bax
- Department of Cardiology, Heart Lung Center, Leiden University Medical Center, Leiden, the Netherlands
| | - Hyuk-Jae Chang
- Yonsei-Cedars-Sinai Integrative Cardiovascular Imaging Research Center, Yonsei University College of Medicine, Yonsei University Health System, South Korea; Division of Cardiology, Severance Cardiovascular Hospital, Yonsei University College of Medicine, Yonsei University Health System, Seoul, South Korea
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Van Cauteren T, Tanaka K, Belsack D, Van Gompel G, Kersemans V, Jochmans K, Droogmans S, de Mey J, Buls N. Potential increase in radiation-induced DNA double-strand breaks with higher doses of iodine contrast during coronary CT angiography. Med Phys 2021; 48:7526-7533. [PMID: 34564862 PMCID: PMC9293077 DOI: 10.1002/mp.15253] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2021] [Revised: 06/25/2021] [Accepted: 09/14/2021] [Indexed: 11/09/2022] Open
Abstract
Purpose To investigate the contrast media iodine dose dependency of radiation‐induced DNA double‐strand breaks (DSBs) during a coronary computed tomography angiography (CCTA) scan. Methods This prospective patient study was approved by the ethical committee. Between November 2018 and July 2019, 50 patients (31 males and 19 females, mean age 64 years) were included in the study, 45 CCTA and five noncontrast‐enhanced (NCE) cardiac computed tomography (CT) patients. A single‐heartbeat scan protocol with a patient‐tailored contrast media injection protocol was used, administering a patient‐specific iodine dose. DNA double‐strand breaks were quantified using a γH2AX foci assay on peripheral blood lymphocytes. The net amount of γH2AX/cell was normalized to the individual patient CT dose by the size‐specific dose estimate (SSDE). Correlation between the administered and blood‐iodine dose and the SSDE normalized amount of DNA DSBs was investigated using a Pearson correlation test. Results CCTA patients were scanned with a mean CTDIvol of 10.6 ± 5.6 mGy, corresponding to a mean SSDE of 11.3 ± 5.3 mGy while the NCE cardiac CT patients were scanned with a mean CTDIvol of 6.00 ± 1.8 mGy, corresponding to a mean SSDE of 6.6 ± 2.7 mGy. The administered iodine dose ranged from 16.5 to 34.0 gI in the CCTA patients, resulting in a blood‐iodine dose range from 5.1 to 15.0 gI in the exposed blood volume. A significant linear relationship (r = 0.79, p‐value < 0.001) was observed between the blood iodine dose and SSDE normalized radiation‐induced DNA DSBs. A similar significant linear relationship (r = 0.62, p‐value < 0.001) was observed between the administered iodine dose and SSDE normalized radiation‐induced DNA DSBs. Conclusions This study shows that contrast media iodine dose increases the level of radiation‐induced DNA DSBs in peripheral blood lymphocytes in a linear dose‐dependent manner with CCTA. Importantly, the level of DNA DSBs can be reduced by lowering the administered iodine dose.
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Affiliation(s)
- Toon Van Cauteren
- Department of Radiology, Vrije Universiteit Brussel (VUB), Universitair Ziekenhuis Brussels (UZB), Brussels, Belgium
| | - Kaoru Tanaka
- Department of Radiology, Vrije Universiteit Brussel (VUB), Universitair Ziekenhuis Brussels (UZB), Brussels, Belgium
| | - Dries Belsack
- Department of Radiology, Vrije Universiteit Brussel (VUB), Universitair Ziekenhuis Brussels (UZB), Brussels, Belgium
| | - Gert Van Gompel
- Department of Radiology, Vrije Universiteit Brussel (VUB), Universitair Ziekenhuis Brussels (UZB), Brussels, Belgium
| | - Veerle Kersemans
- Department of Oncology, CRUK/MRC Institute for Radiation Oncology, University of Oxford, Oxford, UK
| | - Kristin Jochmans
- Department of Hematology, Vrije Universiteit Brussel (VUB), Universitair Ziekenhuis Brussels (UZB), Brussels, Belgium
| | - Steven Droogmans
- Department of Cardiology, Vrije Universiteit Brussel (VUB), Universitair Ziekenhuis Brussels (UZB), Brussels, Belgium
| | - Johan de Mey
- Department of Radiology, Vrije Universiteit Brussel (VUB), Universitair Ziekenhuis Brussels (UZB), Brussels, Belgium
| | - Nico Buls
- Department of Radiology, Vrije Universiteit Brussel (VUB), Universitair Ziekenhuis Brussels (UZB), Brussels, Belgium
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Assessment of imaging protocol and patient radiation exposure in pediatric computed tomography angiography. Radiat Phys Chem Oxf Engl 1993 2020. [DOI: 10.1016/j.radphyschem.2020.108807] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Yuan W, Qu TT, Wang HJ, Wang MY, Qu Y, Niu G, Yang J. Coronary CT Angiography Using Low Iodine Delivery Rate and Tube Voltage Determined by Body Mass Index: Superiority in Clinical Practice. Curr Med Sci 2019; 39:825-830. [PMID: 31612403 DOI: 10.1007/s11596-019-2112-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Revised: 05/23/2019] [Indexed: 12/24/2022]
Abstract
To explore the feasibility and superiority of iodine delivery rate (IDR) and tube voltage determined by patients' body mass index (BMI) in coronary CT angiography (CCTA), a total of 1567 patients undertaking CCTA during Feb. and Dec. 2016 were enrolled and divided into two groups. In the control group, the IDR and tube voltage were fixed, while in the experimental group, the IDR and tube voltage were determined by patients' BMI. The volume of iodinated contrast media (ICM), extravasation rate, extravasation volume, extravasation recovery interval, incidence rate of adverse reactions, effective dose (ED) and image quality of the two groups were compared. The experiments demonstrated that the ICM volume, extravasation rate, extravasation volume, extravasation recovery interval, incidence of adverse reactions and ED were lower or shorter in the experimental group than in the control group, and the differences were statistically significant (all P<0.05). However, there were no significant differences in the mean CT value, image noise, signal to noise ratio and contrast to noise ratio between the two groups (all P<0.05), which were consistent with the diagnosticians' subjective evaluation outcomes. Our findings suggested that in CCTA, it is feasible to determine the IDR and tube voltage based on patients' BMI; low tube voltage and IDR are superior to the fixed tube voltage and IDR and are worthy of clinical promotion.
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Affiliation(s)
- Wang Yuan
- Department of Diagnostic Radiology, the First Hospital of Medical Science Centre, Xi'an Jiaotong University, Xi'an, 710061, China
| | - Ting-Ting Qu
- Department of Diagnostic Radiology, the First Hospital of Medical Science Centre, Xi'an Jiaotong University, Xi'an, 710061, China
| | - Hui-Juan Wang
- Department of Dermatology, the Ninth Hospital of Xi'an, Xi'an, 710054, China
| | - Mei-Yu Wang
- Department of Diagnostic Radiology, the First Hospital of Medical Science Centre, Xi'an Jiaotong University, Xi'an, 710061, China
| | - Yuan Qu
- Department of Diagnostic Radiology, the First Hospital of Medical Science Centre, Xi'an Jiaotong University, Xi'an, 710061, China
| | - Gang Niu
- Department of Diagnostic Radiology, the First Hospital of Medical Science Centre, Xi'an Jiaotong University, Xi'an, 710061, China
| | - Jian Yang
- Department of Diagnostic Radiology, the First Hospital of Medical Science Centre, Xi'an Jiaotong University, Xi'an, 710061, China.
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Baliyan V, Scholtz JE, Kordbacheh H, Hedgire S, Ghoshhajra BB. False-Negative Low Tube Voltage Coronary CT Angiography: High Intravascular Attenuation at Coronary CT Angiography Can Mask Calcified Plaques. Radiol Cardiothorac Imaging 2019; 1:e190039. [PMID: 33778520 PMCID: PMC7977955 DOI: 10.1148/ryct.2019190039] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Revised: 07/08/2019] [Accepted: 08/01/2019] [Indexed: 11/11/2022]
Abstract
PURPOSE To determine the impact of low tube voltage coronary CT angiography on detection of subclinical atherosclerosis. MATERIALS AND METHODS Retrospective sampling of an emergency department coronary CT angiography registry was performed. All patients in the registry underwent a noncontrast coronary artery calcium (CAC) scoring scan at 120 kV before coronary CT angiography. The study sample (n = 264) constituted patients with subclinical atherosclerosis (Coronary Artery Disease Reporting and Data System™ [CAD-RADS] 1 or 2) randomly mixed one-to-one with patients without atherosclerosis (CAD-RADS 0). The patients with coronary CT angiography performed at 70-90 kV were considered the low tube voltage group (n = 159) and patients with coronary CT angiography performed at 100-120 kV were considered the standard tube voltage group (n = 105). The number of coronary plaques and overall CAD-RADS classification (per patient) were evaluated twice: initially, by reading coronary CT angiography alone, and then, by coronary CT angiography in combination with a CAC scan. Considering the combined reading (CT angiography plus CAC scan) as the reference standard, the performance of coronary CT angiography alone was assessed for plaque detection and appropriate CAD-RADS (per patient) classification. The comparisons were made between the low tube voltage and standard tube voltage groups by using a Fisher exact test and χ2 test for proportions and a Mann-Whitney test and Kruskal-Wallis test for means. RESULTS In total, 455 plaques were identified in 118 patients (70 of 159 patients in the low tube voltage group; 48 of 105 in the standard tube voltage group). When reading coronary CT angiographic images alone, 97 of 455 (21%) plaques were missed that led to an incorrect CAD-RADS classification in 16 of 264 (6%) studies (interpreted as CAD-RADS 0 instead of CAD-RADS 1 or 2). Missed plaques were significantly more frequent in the low tube voltage group versus the standard tube voltage group (41% [85 of 206] vs 5% [12 of 249], respectively; P < .001). Incorrect CAD-RADS classification was also seen more commonly in the low tube voltage group (8.8% [14 of 159] vs 2% [two of 105]; P = .01), typically at low plaque burden (median CAC score, 1; range, 1-4). Calcified plaques that appeared isodense to luminal contrast material attenuation were seen more frequently in the low tube voltage group compared with the standard tube voltage group (20% [32 of 159] vs 7.6% [eight of 105], respectively; P = .005). CONCLUSION Coronary artery plaques may be missed at low tube voltage coronary CT angiographic examination performed without a concomitant CAC scan.© RSNA, 2019Supplemental material is available for this article.See also the commentary by Truong in this issue.
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Affiliation(s)
- Vinit Baliyan
- From the Division of Cardiovascular Imaging (V.B., J.E.S., S.H., B.B.G.) and Department of Radiology (V.B., J.E.S., H.K., S.H., B.B.G.), Massachusetts General Hospital, 55 Fruit St, White 270, Boston, MA 02114; and Institute for Diagnostic and Interventional Radiology, University Hospital Frankfurt, Frankfurt, Germany (J.E.S.)
| | - Jan-Erik Scholtz
- From the Division of Cardiovascular Imaging (V.B., J.E.S., S.H., B.B.G.) and Department of Radiology (V.B., J.E.S., H.K., S.H., B.B.G.), Massachusetts General Hospital, 55 Fruit St, White 270, Boston, MA 02114; and Institute for Diagnostic and Interventional Radiology, University Hospital Frankfurt, Frankfurt, Germany (J.E.S.)
| | - Hamed Kordbacheh
- From the Division of Cardiovascular Imaging (V.B., J.E.S., S.H., B.B.G.) and Department of Radiology (V.B., J.E.S., H.K., S.H., B.B.G.), Massachusetts General Hospital, 55 Fruit St, White 270, Boston, MA 02114; and Institute for Diagnostic and Interventional Radiology, University Hospital Frankfurt, Frankfurt, Germany (J.E.S.)
| | - Sandeep Hedgire
- From the Division of Cardiovascular Imaging (V.B., J.E.S., S.H., B.B.G.) and Department of Radiology (V.B., J.E.S., H.K., S.H., B.B.G.), Massachusetts General Hospital, 55 Fruit St, White 270, Boston, MA 02114; and Institute for Diagnostic and Interventional Radiology, University Hospital Frankfurt, Frankfurt, Germany (J.E.S.)
| | - Brian B. Ghoshhajra
- From the Division of Cardiovascular Imaging (V.B., J.E.S., S.H., B.B.G.) and Department of Radiology (V.B., J.E.S., H.K., S.H., B.B.G.), Massachusetts General Hospital, 55 Fruit St, White 270, Boston, MA 02114; and Institute for Diagnostic and Interventional Radiology, University Hospital Frankfurt, Frankfurt, Germany (J.E.S.)
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Hubbard L, Malkasian S, Zhao Y, Abbona P, Molloi S. Contrast-to-Noise Ratio Optimization in Coronary Computed Tomography Angiography: Validation in a Swine Model. Acad Radiol 2019; 26:e115-e125. [PMID: 30172714 DOI: 10.1016/j.acra.2018.06.026] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2018] [Revised: 06/28/2018] [Accepted: 06/29/2018] [Indexed: 11/17/2022]
Abstract
RATIONALE AND OBJECTIVES The accuracy of coronary computed tomography (CT) angiography depends upon the degree of coronary enhancement as compared to the background noise. Unfortunately, coronary contrast-to-noise ratio (CNR) optimization is difficult on a patient-specific basis. Hence, the objective of this study was to validate a new combined diluted test bolus and CT angiography protocol for improved coronary enhancement and CNR. MATERIALS AND METHODS The combined diluted test bolus and CT angiography protocol was validated in six swine (28.9 ± 2.7 kg). Specifically, the aortic and coronary enhancement and CNR of a standard CT angiography protocol, and a new combined diluted test bolus and CT angiography protocol were compared to a reference retrospective CT angiography protocol. Comparisons for all data were made using box plots, t tests, regression, Bland-Altman, root-mean-square error and deviation, as well as Lin's concordance correlation. RESULTS The combined diluted test bolus and CT angiography protocol was found to improve aortic and coronary enhancement by 26% and 13%, respectively, as compared to the standard CT angiography protocol. More importantly, the combined protocol was found to improve aortic and coronary CNR by 29% and 20%, respectively, as compared to the standard protocol. CONCLUSION A new combined diluted test bolus and CT angiography protocol was shown to improve coronary enhancement and CNR as compared to an existing standard CT angiography protocol.
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Affiliation(s)
- Logan Hubbard
- Department of Radiological Sciences, Medical Sciences I, B-140, University of California, Irvine, Irvine, CA 92697
| | - Shant Malkasian
- Department of Radiological Sciences, Medical Sciences I, B-140, University of California, Irvine, Irvine, CA 92697
| | - Yixiao Zhao
- Department of Radiological Sciences, Medical Sciences I, B-140, University of California, Irvine, Irvine, CA 92697
| | - Pablo Abbona
- Department of Radiological Sciences, Medical Sciences I, B-140, University of California, Irvine, Irvine, CA 92697
| | - Sabee Molloi
- Department of Radiological Sciences, Medical Sciences I, B-140, University of California, Irvine, Irvine, CA 92697.
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Image quality and diagnostic value of ultra low-voltage, ultra low-contrast coronary CT angiography. Eur Radiol 2019; 29:3678-3685. [DOI: 10.1007/s00330-019-06111-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Revised: 01/28/2019] [Accepted: 02/13/2019] [Indexed: 10/27/2022]
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10
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Zabak E, Omar H, Boothe E, Tenorio L, Guild J, Abbara S, Chhabra A. Radiation dose reduction for musculoskeletal computed tomography of the pelvis with preserved image quality. Skeletal Radiol 2019; 48:375-385. [PMID: 30155628 DOI: 10.1007/s00256-018-3039-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/12/2017] [Revised: 07/23/2018] [Accepted: 07/30/2018] [Indexed: 02/02/2023]
Abstract
OBJECTIVE To analyze the impact of pelvic computed tomography (CT) technique optimization on estimated dose and subjective and objective image quality. MATERIALS AND METHODS An institutional review board (IRB)-approved retrospective records review was performed with waived informed consent. Five CT scanners (various manufacturers/models) were standardized to match the lowest dose profile on campus via subjective assessment of clinical images by experienced musculoskeletal radiologists. The lowest dose profile had previously been established through image assessment by experienced musculoskeletal radiologists after a department-wide radiation dose reduction initiative. A consecutive series of 60 pre- and 59 post-optimization bony pelvis CTs were analyzed by two residents, who obtained signal-to-noise ratio for femoral cortex and marrow, gluteus medius muscle, and subcutaneous and visceral fat in a standardized fashion. Two blinded attending radiologists ranked image quality from poor to excellent. RESULTS Pre- and post-optimization subjects exhibited no difference in gender, age, or BMI (p > 0.2). Mean CT dose index (CTDIvol) and dose-length product (DLP) decreased by approximately 45%, from 39± 14 to 18± 12 mGy (p < 0.0001) and 1,227± 469 to 546± 384 mGy-cm (p < 0.0001). Lower body mass index (BMI) was associated with a larger dose reduction and higher BMI with higher DLP regardless of pre- or post-optimization examination. Inter-observer agreement was 0.64-0.92 for SNR measurements. Cortex SNR increased significantly for both observers (p < 0.02). Although qualitative image quality significantly decreased for one observer (p < 0.01), adequate mean quality (3.3 out of 5) was maintained for both observers. CONCLUSION Subjective and objective image quality for pelvic CT examination remains adequate, despite a substantially reduced radiation dose.
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Affiliation(s)
- Elaina Zabak
- UT Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX, 75390-9178, USA
| | - Hythem Omar
- UT Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX, 75390-9178, USA
| | - Ethan Boothe
- UT Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX, 75390-9178, USA.
| | - Lulu Tenorio
- UT Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX, 75390-9178, USA
| | - Jeffrey Guild
- UT Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX, 75390-9178, USA
| | - Suhny Abbara
- UT Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX, 75390-9178, USA
| | - Avneesh Chhabra
- UT Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX, 75390-9178, USA
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11
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Evaluating Lens Dose Reduction in Pediatric Neuroradiology Examinations Using Automated Kilovoltage Selection Software. AJR Am J Roentgenol 2018; 211:635-640. [DOI: 10.2214/ajr.17.19089] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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12
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Kalra MK, Becker HC, Enterline DS, Lowry CR, Molvin LZ, Singh R, Rybicki FJ. Contrast Administration in CT: A Patient-Centric Approach. J Am Coll Radiol 2018; 16:295-301. [PMID: 30082238 DOI: 10.1016/j.jacr.2018.06.026] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Revised: 06/19/2018] [Accepted: 06/22/2018] [Indexed: 12/16/2022]
Abstract
Patient-centric care has garnered the attention of the radiology community. The authors describe a patient-centric approach to iodinated contrast administration designed to optimize the diagnostic yield of contrast-enhanced CT while minimizing patient iodine load and exposure to ionizing radiation, thereby enhancing patient safety while providing reasonable diagnostic efficacy. Patient-centric CT hardware settings and contrast media administration are important considerations for clinical CT quality and safety.
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Affiliation(s)
- Mannudeep K Kalra
- Department of Radiology, Massachusetts General Hospital, Boston, Massachusetts; Harvard Medical School, Boston, Massachusetts.
| | - Hans-Christoph Becker
- Department of Radiology, Stanford University, Stanford, California; Department of Radiology, Ludwig-Maximilians-Universität, Munich, Germany
| | | | - Carolyn R Lowry
- Department of Radiology, Duke University, Durham, North Carolina
| | - Lior Z Molvin
- Department of Radiology, Stanford University, Palo Alto, California; Stanford Healthcare, Palo Alto, California
| | - Ramandeep Singh
- Department of Radiology, Massachusetts General Hospital, Boston, Massachusetts; Harvard Medical School, Boston, Massachusetts
| | - Frank J Rybicki
- Department of Radiology, The University of Ottawa, Ottawa, Ontario, Canada; The Ottawa Hospital Research Institute, Ottawa, Ontario, Canada
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13
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Wang XP, Zhu XM, Zhu YS, Liu WY, Yang XH, Huang WW, Xu Y, Tang LJ. Automatic tube potential selection with tube current modulation in coronary CT angiography: Can it achieve consistent image quality among various individuals? Exp Ther Med 2018; 16:253-259. [PMID: 29896246 PMCID: PMC5995055 DOI: 10.3892/etm.2018.6158] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2017] [Accepted: 04/06/2018] [Indexed: 11/06/2022] Open
Abstract
The present study included a total of 111 consecutive patients who had undergone coronary computed tomography (CT) angiography, using a first-generation dual-source CT with automatic tube potential selection and tube current modulation. Body weight (BW) and body mass index (BMI) were recorded prior to CT examinations. Image noise and attenuation of the proximal ascending aorta (AA) and descending aorta (DA) at the middle level of the left ventricle were measured. Correlations between BW, BMI and objective image quality were evaluated using linear regression. In addition, two subgroups based on BMI (BMI ≤25 and >25 kg/m2) were analyzed. Subjective image quality, image noise, the signal-to-noise ratio (SNR) and the contrast-to-noise ratio (CNR) were all compared between those. The image noise of the AA increased with the BW and BMI (BW: r=0.453, P<0.001; BMI: r=0.545, P<0.001). The CNR and SNR of the AA were inversely correlated with BW and BMI, respectively. The image noise of the DA and the CNR and SNR of the DA exhibited a similar association to those with the BW or BMI. The BMI >25 kg/m2 group had a significant increase in image noise (33.1±6.9 vs. 27.8±4.0 HU, P<0.05) and a significant reduction in CNR and SNR, when compared with those in the BMI ≤25 kg/m2 group (CNR: 18.9±4.3 vs. 16.1±3.7, P<0.05; SNR: 16.0±3.8 vs. 13.6±3.2, P<0.05). Patients with a BMI of ≤25 kg/m2 had more coronary artery segments scored as excellent, compared with patients with a BMI of >25 kg/m2 (P=0.02). In conclusion, this method is not able to achieve a consistent objective image quality across the entire patient population. The impact of BW and BMI on objective image quality was not completely eliminated. BMI-based adjustment of the tube potential may achieve a more consistent image quality compared to automatic tube potential selection, particularly in patients with a larger body habitus.
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Affiliation(s)
- Xiao-Ping Wang
- Department of Radiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu 210029, P.R. China
| | - Xiao-Mei Zhu
- Department of Radiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu 210029, P.R. China
| | - Yin-Su Zhu
- Department of Radiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu 210029, P.R. China
| | - Wang-Yan Liu
- Department of Radiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu 210029, P.R. China
| | - Xiao-Han Yang
- Department of Radiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu 210029, P.R. China
| | - Wei-Wei Huang
- Department of Radiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu 210029, P.R. China
| | - Yi Xu
- Department of Radiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu 210029, P.R. China
| | - Li-Jun Tang
- Department of Radiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu 210029, P.R. China
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14
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Lee HS, Suh YJ, Han K, Kim JY, Chang S, Im DJ, Hong YJ, Lee HJ, Hur J, Kim YJ, Choi BW. Effectiveness of automatic tube potential selection with tube current modulation in coronary CT angiography for obese patients: Comparison with a body mass index-based protocol using the propensity score matching method. PLoS One 2018; 13:e0190584. [PMID: 29304060 PMCID: PMC5755873 DOI: 10.1371/journal.pone.0190584] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2017] [Accepted: 11/21/2017] [Indexed: 01/09/2023] Open
Abstract
Background Reduced image quality from increased X-ray scatter and image noise can be problematic when coronary computed tomography angiography (CCTA) imaging is performed in obese patients. The aim of this study was to compare the image quality and radiation dose obtained using automatic tube potential selection with tube current modulation (APSCM) with those obtained using a body mass index (BMI)-based protocol for CCTA in obese patients. Methods A total of 203 consecutive obese (BMI > 30 kg/m2) patients were retrospectively enrolled, of whom 96 underwent CCTA with APSCM and 107 underwent a BMI-based protocol. After applying the propensity score matching method, the clinical parameters, subjective and objective image quality, and radiation dose were compared between the APSCM group and the matched BMI-based group. These parameters were also compared among different tube potential subgroups. Results No significant differences were observed between the APSCM group and the BMI-based group with respect to image quality or radiation dose assessment (p > 0.05). Twenty patients (21%) examined with 140 kV in the APSCM group were exposed to significantly more radiation (p < 0.05) than patients in the BMI-based group or patients in the other APSCM kV subgroups; significant improvement in image quality was not observed in the 140 kV subgroup. Patients with a high BMI and a large effective diameter tended to be examined with 140 kV (p < 0.05). Conclusion The use of APSCM for CCTA in obese patients did not significantly reduce the radiation dose or improve image quality compared with those in the matched BMI-based group. Our data indicate that it is better to avoid using APSCM when 140 kV is automatically selected, due to increased radiation dose and lack of significant improvement in image quality.
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Affiliation(s)
- Hong Seon Lee
- Department of Radiology, Research Institute of Radiological Science, Severance Hospital, Yonsei University College of Medicine, Korea
| | - Young Joo Suh
- Department of Radiology, Research Institute of Radiological Science, Severance Hospital, Yonsei University College of Medicine, Korea
- * E-mail:
| | - Kyunghwa Han
- Department of Radiology, Research Institute of Radiological Science, Severance Hospital, Yonsei University College of Medicine, Korea
| | - Jin Young Kim
- Department of Radiology, Research Institute of Radiological Science, Severance Hospital, Yonsei University College of Medicine, Korea
| | - Suyon Chang
- Department of Radiology, Research Institute of Radiological Science, Severance Hospital, Yonsei University College of Medicine, Korea
| | - Dong Jin Im
- Department of Radiology, Research Institute of Radiological Science, Severance Hospital, Yonsei University College of Medicine, Korea
| | - Yoo Jin Hong
- Department of Radiology, Research Institute of Radiological Science, Severance Hospital, Yonsei University College of Medicine, Korea
| | - Hye-Jeong Lee
- Department of Radiology, Research Institute of Radiological Science, Severance Hospital, Yonsei University College of Medicine, Korea
| | - Jin Hur
- Department of Radiology, Research Institute of Radiological Science, Severance Hospital, Yonsei University College of Medicine, Korea
| | - Young Jin Kim
- Department of Radiology, Research Institute of Radiological Science, Severance Hospital, Yonsei University College of Medicine, Korea
| | - Byoung Wook Choi
- Department of Radiology, Research Institute of Radiological Science, Severance Hospital, Yonsei University College of Medicine, Korea
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15
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Abstract
OPINION STATEMENT Early identification of atherosclerosis and at-risk lesions plays a critical role in reducing the burden of cardiovascular disease. While invasive coronary angiography serves as the gold standard for diagnosing coronary artery disease, non-invasive imaging techniques provide visualization of both anatomical and functional atherosclerotic processes prior to clinical presentation. The development of cardiac positron emission tomography (PET) has greatly enhanced our capability to diagnose and treat patients with early stages of atherosclerosis. Cardiac PET is a powerful, versatile non-invasive diagnostic tool with utility in the identification of high-risk plaques, myocardial perfusion defects, and viable myocardial tissue. Cardiac PET allows for comparisons of myocardial function both at time of rest and stress, providing accurate assessments of both myocardial perfusion and viability. Furthermore, novel PET techniques with unique radiotracers yield clinically relevant data on high-risk plaques in active progressive atherosclerosis. While PET exercise stress tests were previously difficult to perform given short radiotracer half-life, the development of the novel radiotracer Flurpiridaz F-18 provides a promising future for PET exercise stress imaging. In addition, hybrid imaging with computed tomography angiography (CTA) and cardiac magnetic resonance (CMR) provides integration of cardiac function and structure. In this review article, we discuss the principles of cardiac PET, the clinical applications of PET in diagnosing and prognosticating patients at risk for future cardiovascular events, compare PET with other non-invasive cardiac imaging modalities, and discuss future applications of PET in CVD evaluation and management.
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Affiliation(s)
- Brian M Salata
- Weill Cornell Medicine, 520 E 70th Street, M-507, New York, NY, 10021, USA
| | - Parmanand Singh
- Department of Cardiology, Weill Cornell Medicine, 520 E 70th Street Starr Pavilion, 4th Floor, New York, NY, 10021, USA.
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16
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Hill KD, Frush DP, Han BK, Abbott BG, Armstrong AK, DeKemp RA, Glatz AC, Greenberg SB, Herbert AS, Justino H, Mah D, Mahesh M, Rigsby CK, Slesnick TC, Strauss KJ, Trattner S, Viswanathan MN, Einstein AJ. Radiation Safety in Children With Congenital and Acquired Heart Disease: A Scientific Position Statement on Multimodality Dose Optimization From the Image Gently Alliance. JACC Cardiovasc Imaging 2017; 10:797-818. [PMID: 28514670 PMCID: PMC5542588 DOI: 10.1016/j.jcmg.2017.04.003] [Citation(s) in RCA: 71] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/13/2017] [Revised: 04/25/2017] [Accepted: 04/28/2017] [Indexed: 02/07/2023]
Abstract
There is a need for consensus recommendations for ionizing radiation dose optimization during multimodality medical imaging in children with congenital and acquired heart disease (CAHD). These children often have complex diseases and may be exposed to a relatively high cumulative burden of ionizing radiation from medical imaging procedures, including cardiac computed tomography, nuclear cardiology studies, and fluoroscopically guided diagnostic and interventional catheterization and electrophysiology procedures. Although these imaging procedures are all essential to the care of children with CAHD and have contributed to meaningfully improved outcomes in these patients, exposure to ionizing radiation is associated with potential risks, including an increased lifetime attributable risk of cancer. The goal of these recommendations is to encourage informed imaging to achieve appropriate study quality at the lowest achievable dose. Other strategies to improve care include a patient-centered approach to imaging, emphasizing education and informed decision making and programmatic approaches to ensure appropriate dose monitoring. Looking ahead, there is a need for standardization of dose metrics across imaging modalities, so as to encourage comparative effectiveness studies across the spectrum of CAHD in children.
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Affiliation(s)
- Kevin D Hill
- Department of Pediatrics, Duke University Medical Center, Durham, North Carolina (Image Gently Alliance representative)
| | - Donald P Frush
- Department of Radiology, Duke University Medical Center, Durham, North Carolina (Image Gently Alliance and SPR representative)
| | - B Kelly Han
- Department of Pediatric Cardiology, Children's Heart Clinic at The Children's Hospitals and Clinics of Minnesota and the Minneapolis Heart Institute, Minneapolis, Minnesota (SCCT representative)
| | - Brian G Abbott
- Department of Medicine, Warren Alpert Medical School of Brown University, Providence, Rhode Island (ASNC representative)
| | - Aimee K Armstrong
- Department of Pediatrics, Nationwide Children's Hospital, Ohio State University, Columbus, Ohio (ACC representative)
| | - Robert A DeKemp
- Department of Medicine, University of Ottawa Heart Institute, Ottawa, Ontario, Canada (SNMMI representative)
| | - Andrew C Glatz
- Department of Pediatrics, Children's Hospital of Philadelphia, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania (Image Gently Alliance representative)
| | - S Bruce Greenberg
- Department of Radiology, Arkansas Children's Hospital, Little Rock, Arkansas (NASCI representative)
| | - Alexander Sheldon Herbert
- Department of Radiology, New York-Presbyterian Morgan Stanley Children's Hospital, New York, New York (ASRT representative)
| | - Henri Justino
- Department of Pediatrics, Texas Children's Hospital, Baylor College of Medicine, Houston, Texas (SCAI representative)
| | - Douglas Mah
- Department of Pediatrics, Boston Children's Hospital, Boston, Massachusetts (PACES representative)
| | - Mahadevappa Mahesh
- Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, Baltimore, Maryland (AAPM representative)
| | - Cynthia K Rigsby
- Department of Medical Imaging, Ann & Robert H. Lurie Children's Hospital of Chicago, Chicago, Illinois; Department of Radiology, Northwestern University Feinberg School of Medicine, Chicago, Illinois (ACR representative)
| | - Timothy C Slesnick
- Department of Pediatrics, Children's Healthcare of Atlanta, Emory University School of Medicine, Atlanta, Georgia (AAP representative)
| | - Keith J Strauss
- Department of Radiology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio (Image Gently Alliance Representative)
| | - Sigal Trattner
- Division of Cardiology, Department of Medicine, Columbia University Medical Center, New York, New York (Image Gently Alliance representative)
| | - Mohan N Viswanathan
- Department of Internal Medicine, Stanford University, Stanford, California (HRS representative)
| | - Andrew J Einstein
- Division of Cardiology, Department of Medicine, and Department of Radiology, Columbia University Medical Center and New York-Presbyterian Hospital, New York, New York (Image Gently Alliance representative).
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17
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Niiniviita H, Kulmala J, Pölönen T, Määttänen H, Järvinen H, Salminen E. Excess of Radiation Burden for Young Testicular Cancer Patients using Automatic Exposure Control and Contrast Agent on Whole-body Computed Tomography Imaging. Radiol Oncol 2017; 51:235-240. [PMID: 28740460 PMCID: PMC5514665 DOI: 10.1515/raon-2017-0012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2016] [Accepted: 02/03/2017] [Indexed: 11/24/2022] Open
Abstract
BACKGROUND The aim of the study was to assess patient dose from whole-body computed tomography (CT) in association with patient size, automatic exposure control (AEC) and intravenous (IV) contrast agent. PATIENTS AND METHODS Sixty-five testicular cancer patients (mean age 28 years) underwent altogether 279 whole-body CT scans from April 2000 to April 2011. The mean number of repeated examinations was 4.3. The GE LightSpeed 16 equipped with AEC and the Siemens Plus 4 CT scanners were used for imaging. Whole-body scans were performed with (216) and without (63) IV contrast. The ImPACT software was used to determine the effective and organ doses. RESULTS Patient doses were independent (p < 0.41) of patient size when the Plus 4 device (mean 7.4 mSv, SD 1.7 mSv) was used, but with the LightSpeed 16 AEC device, the dose (mean 14 mSv, SD 4.6 mSv) increased significantly (p < 0.001) with waist cirfumference. Imaging with the IV contrast agent caused significantly higher (13% Plus 4, 35% LightSpeed 16) exposure than non-contrast imaging (p < 0.001). CONCLUSIONS Great caution on the use of IV contrast agent and careful set-up of the AEC modulation parameters is recommended to avoid excessive radiation exposure on the whole-body CT imaging of young patients.
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Affiliation(s)
- Hannele Niiniviita
- Department of Medical Physics, Turku University Hospital, Turku, Finland
- Department of Diagnostic Radiology, University of Turku, Turku, Finland
| | - Jarmo Kulmala
- Department of Medical Physics, Turku University Hospital, Turku, Finland
- Oncology and Radiotherapy, Turku University Hospital, Turku, Finland
| | - Tuukka Pölönen
- Department of Biostatistics, University of Turku, Turku, Finland
| | - Heli Määttänen
- Department of Medical Physics, Turku University Hospital, Turku, Finland
| | - Hannu Järvinen
- STUK-Radiation and Nuclear Safety Authority, Helsinki, Finland
| | - Eeva Salminen
- Oncology and Radiotherapy, Turku University Hospital, Turku, Finland
- STUK-Radiation and Nuclear Safety Authority, Helsinki, Finland
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18
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Meyersohn NM, Szilveszter B, Staziaki PV, Scholtz JE, Takx RAP, Hoffmann U, Ghoshhajra BB. Coronary CT angiography in the emergency department utilizing second and third generation dual source CT. J Cardiovasc Comput Tomogr 2017; 11:249-257. [PMID: 28506470 DOI: 10.1016/j.jcct.2017.03.002] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/28/2016] [Revised: 03/17/2017] [Accepted: 03/19/2017] [Indexed: 01/28/2023]
Abstract
BACKGROUND Coronary computed tomography angiography (coronary CTA) allows efficient triage of low to intermediate risk patients with suspected acute coronary syndrome (ACS) in the emergency department (ED). Techniques for coronary CTA acquisition in the ED continue to evolve with the establishment of standardized scan protocols and the introduction of newer generations of CT hardware. OBJECTIVES To evaluate qualitative and quantitative image quality and radiation dose exposure of coronary CTA acquired on 2nd versus 3rd generation dual source CT (DSCT) scanners using a standardized institutional scan protocol designed for the ED. METHODS A retrospective observational case-control study was performed of 246 ED patients referred to coronary CTA with suspicion of ACS (56.5% male; mean age 53.3 ± 11.6 years) between October 2013 and August 2015.123 consecutive patients were scanned on 3rd generation DSCT, and a cohort of 123 patients matched by age, BMI and heart rate were identified who had undergone 2nd generation DSCT imaging utilizing the same standard clinical protocol. Qualitative and quantitative image quality parameters and radiation exposures were evaluated. RESULTS Qualitative image quality was significantly higher using 3rd generation DSCT as compared to 2nd generation (p < 0.001). Mean attenuation in the proximal coronary arteries was also significantly higher on 3rd generation DSCT than for 2nd generation (586 HU vs. 426 HU in the left main coronary artery (LM), p < 0.001). Signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) values, however, were lower in 3rd generation DSCT than 2nd generation (SNR 11.2 [9.9-13.4] vs 13.5 [11.0-15.5] and CNR 12.4 [10.9-14.8] vs 15.2 [12.8-17.9] in the LM, p < 0.001). Median effective dose was also lower for 3rd generation DSCT than for 2nd generation (2.9 [2.3-5.0] mSv and 3.7 mSv [2.5-5.7], respectively) although this trend did not reach statistical significance (p = 0.065). CONCLUSION Qualitative image quality and mean CT attenuation values of the assessed coronary segments were significantly higher using 3rd generation DSCT. SNR and CNR were lower on 3rd generation DSCT, however this was accompanied by a trend toward lower radiation dose exposure when using the same standard institutional protocol.
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Affiliation(s)
- Nandini M Meyersohn
- Cardiac MR PET CT Program, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA; Department of Radiology, Massachusetts General Hospital, Boston, MA, USA.
| | - Balint Szilveszter
- Cardiac MR PET CT Program, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Pedro V Staziaki
- Cardiac MR PET CT Program, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Jan-Erik Scholtz
- Cardiac MR PET CT Program, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Richard A P Takx
- Cardiac MR PET CT Program, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Udo Hoffmann
- Cardiac MR PET CT Program, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA; Department of Radiology, Massachusetts General Hospital, Boston, MA, USA
| | - Brian B Ghoshhajra
- Cardiac MR PET CT Program, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA; Department of Radiology, Massachusetts General Hospital, Boston, MA, USA
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19
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Masuda T, Funama Y, Kiguchi M, Imada N, Oku T, Sato T, Awai K. Radiation dose reduction based on CNR index with low-tube voltage scan for pediatric CT scan: experimental study using anthropomorphic phantoms. SPRINGERPLUS 2016; 5:2064. [PMID: 27995041 PMCID: PMC5133217 DOI: 10.1186/s40064-016-3715-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/09/2016] [Accepted: 11/21/2016] [Indexed: 12/13/2022]
Abstract
Background To figure out the relationship between image noise and contrast noise ratio (CNR) at different tube voltages, using anthropomorphic new-born and 1-year-old phantoms, and to discuss the feasibility of radiation dose reduction, based on the obtained CNR index from image noise. We performed helical scans of the anthropomorphic new-born and 1-year-old phantoms. The CT numbers of the simulated aorta and image noise of the simulated mediastinum were measured; then CNR was calculated on 80, 100, and 120-kVp images reconstructed with filtered back projection (FBP) and iterative reconstruction (IR). We also measured the center and surface dose in the case of CNR of 14 using radio-photoluminescence glass dosimeters. Results The CT number of the simulated aorta was increased with decreasing tube voltage from 120 to 80 kVp (362.5–535.1 HU for the new-born, 358.9–532.6 HU for the 1-year-old). At CNR of 14, the center dose was 0.4, 0.6 and 0.9 mGy at FBP and 0.5, 0.6 and 0.9 mGy at IR and with the new-born phantom acquired at 80, 100 and 120 kVp, respectively. The center dose for FBP image was reduced by 56% at 80 kVp, 34% at 100 kVp for the new-born and 36% at 80 kVp, 22% at 100 kVp for the 1-year-old compared with that at 120 kVp. We obtained a relationship between image noise and CNR at different tube voltages using the anthropomorphic new-born and 1-year-old phantoms. Conclusion The use of index of CNR with low-tube voltage may achieve further radiation dose reduction in pediatric CT examination.
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Affiliation(s)
- Takanori Masuda
- Department of Radiological Technology, Tsuchiya General Hospital, Nakajima-cho 3-30, Naka-ku, Hiroshima, 730-8655 Japan ; Department of Diagnostic Radiology, Graduate School of Biomedical Sciences, Hiroshima University, Hiroshima, Japan
| | - Yoshinori Funama
- Department of Medical Physics, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan
| | - Masao Kiguchi
- Department of Diagnostic Radiology, Graduate School of Biomedical Sciences, Hiroshima University, Hiroshima, Japan
| | - Naoyuki Imada
- Department of Radiological Technology, Tsuchiya General Hospital, Nakajima-cho 3-30, Naka-ku, Hiroshima, 730-8655 Japan
| | - Takayuki Oku
- Department of Radiological Technology, Tsuchiya General Hospital, Nakajima-cho 3-30, Naka-ku, Hiroshima, 730-8655 Japan
| | - Tomoyasu Sato
- Department of Diagnostic Radiology, Tsuchiya General Hospital, Nakajima-cho 3-30, Naka-ku, Hiroshima, 730-8655 Japan
| | - Kazuo Awai
- Department of Diagnostic Radiology, Graduate School of Biomedical Sciences, Hiroshima University, Hiroshima, Japan
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20
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Kalisz K, Buethe J, Saboo SS, Abbara S, Halliburton S, Rajiah P. Artifacts at Cardiac CT: Physics and Solutions. Radiographics 2016; 36:2064-2083. [PMID: 27768543 DOI: 10.1148/rg.2016160079] [Citation(s) in RCA: 120] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Computed tomography is vulnerable to a wide variety of artifacts, including patient- and technique-specific artifacts, some of which are unique to imaging of the heart. Motion is the most common source of artifacts and can be caused by patient, cardiac, or respiratory motion. Cardiac motion artifacts can be reduced by decreasing the heart rate and variability and the duration of data acquisition; adjusting the placement of the data window within a cardiac cycle; performing single-heartbeat scanning; and using multisegment reconstruction, motion-correction algorithms, and electrocardiographic editing. Respiratory motion artifacts can be minimized with proper breath holding and shortened scan duration. Partial volume averaging is caused by the averaging of attenuation values from all tissue contained within a voxel and can be reduced by improving the spatial resolution, using a higher x-ray energy, or displaying images with a wider window width. Beam-hardening artifacts are caused by the polyenergetic nature of the x-ray beam and can be reduced by using x-ray filtration, applying higher-energy x-rays, altering patient position, modifying contrast material protocols, and applying certain reconstruction algorithms. Metal artifacts are complex and have multiple causes, including x-ray scatter, underpenetration, motion, and attenuation values that exceed the typical dynamic range of Hounsfield units. Quantum mottle or noise is caused by insufficient penetration of tissue and can be improved by increasing the tube current or peak tube potential, reconstructing thicker sections, increasing the rotation time, using appropriate patient positioning, and applying iterative reconstruction algorithms. ©RSNA, 2016.
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Affiliation(s)
- Kevin Kalisz
- From the Department of Radiology, University Hospitals Cleveland Medical Center, Cleveland, Ohio (K.K., J.B.); Department of Radiology, Cardiothoracic Imaging, UT Southwestern Medical Center, E6.120 B, Mail Code 9316, 5323 Harry Hines Blvd, Dallas, TX 75390-8896 (S.S.S., S.A., P.R.); and Philips Healthcare, Cleveland, Ohio (S.H.)
| | - Ji Buethe
- From the Department of Radiology, University Hospitals Cleveland Medical Center, Cleveland, Ohio (K.K., J.B.); Department of Radiology, Cardiothoracic Imaging, UT Southwestern Medical Center, E6.120 B, Mail Code 9316, 5323 Harry Hines Blvd, Dallas, TX 75390-8896 (S.S.S., S.A., P.R.); and Philips Healthcare, Cleveland, Ohio (S.H.)
| | - Sachin S Saboo
- From the Department of Radiology, University Hospitals Cleveland Medical Center, Cleveland, Ohio (K.K., J.B.); Department of Radiology, Cardiothoracic Imaging, UT Southwestern Medical Center, E6.120 B, Mail Code 9316, 5323 Harry Hines Blvd, Dallas, TX 75390-8896 (S.S.S., S.A., P.R.); and Philips Healthcare, Cleveland, Ohio (S.H.)
| | - Suhny Abbara
- From the Department of Radiology, University Hospitals Cleveland Medical Center, Cleveland, Ohio (K.K., J.B.); Department of Radiology, Cardiothoracic Imaging, UT Southwestern Medical Center, E6.120 B, Mail Code 9316, 5323 Harry Hines Blvd, Dallas, TX 75390-8896 (S.S.S., S.A., P.R.); and Philips Healthcare, Cleveland, Ohio (S.H.)
| | - Sandra Halliburton
- From the Department of Radiology, University Hospitals Cleveland Medical Center, Cleveland, Ohio (K.K., J.B.); Department of Radiology, Cardiothoracic Imaging, UT Southwestern Medical Center, E6.120 B, Mail Code 9316, 5323 Harry Hines Blvd, Dallas, TX 75390-8896 (S.S.S., S.A., P.R.); and Philips Healthcare, Cleveland, Ohio (S.H.)
| | - Prabhakar Rajiah
- From the Department of Radiology, University Hospitals Cleveland Medical Center, Cleveland, Ohio (K.K., J.B.); Department of Radiology, Cardiothoracic Imaging, UT Southwestern Medical Center, E6.120 B, Mail Code 9316, 5323 Harry Hines Blvd, Dallas, TX 75390-8896 (S.S.S., S.A., P.R.); and Philips Healthcare, Cleveland, Ohio (S.H.)
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Kalra MK, Sodickson AD, Mayo-Smith WW. CT Radiation: Key Concepts for Gentle and Wise Use. Radiographics 2016; 35:1706-21. [PMID: 26466180 DOI: 10.1148/rg.2015150118] [Citation(s) in RCA: 71] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Use of computed tomography (CT) in medicine comes with the responsibility of its appropriate (wise) and safe (gentle) application to obtain required diagnostic information with the lowest possible dose of radiation. CT provides useful information that may not be available with other imaging modalities in many clinical situations in children and adults. Inappropriate or excessive use of CT should be avoided, especially if required information can be obtained in an accurate and time-efficient manner with other modalities that require a lower radiation dose, or non-radiation-based imaging modalities such as ultrasonography and magnetic resonance imaging. In addition to appropriate use of CT, the radiology community also must monitor scanning practices and protocols. When appropriate, high-contrast regions and lesions should be scanned with reduced dose, but overly zealous dose reduction should be avoided for assessment of low-contrast lesions. Patients' cross-sectional body size should be taken into account to deliver lower radiation dose to smaller patients and children. Wise use of CT scanning with gentle application of radiation dose can help maximize the diagnostic value of CT, as well as address concerns about potential risks of radiation. In this article, key concepts in CT radiation dose are reviewed, including CT dose descriptors; radiation doses from CT procedures; and factors and technologies that affect radiation dose and image quality, including their use in creating dose-saving protocols. Also discussed are the contributions of radiation awareness campaigns such as the Image Gently and Image Wisely campaigns and the American College of Radiology Dose Index Registry initiatives.
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Affiliation(s)
- Mannudeep K Kalra
- From the Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, Mass (M.K.K.); and Department of Radiology, Brigham and Women's Hospital, 75 Francis St, Boston, MA 02115 and Harvard Medical School, Boston, Mass (A.D.S., W.W.M.S.)
| | - Aaron D Sodickson
- From the Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, Mass (M.K.K.); and Department of Radiology, Brigham and Women's Hospital, 75 Francis St, Boston, MA 02115 and Harvard Medical School, Boston, Mass (A.D.S., W.W.M.S.)
| | - William W Mayo-Smith
- From the Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, Mass (M.K.K.); and Department of Radiology, Brigham and Women's Hospital, 75 Francis St, Boston, MA 02115 and Harvard Medical School, Boston, Mass (A.D.S., W.W.M.S.)
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22
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Durmus T, Luhur R, Daqqaq T, Schwenke C, Knobloch G, Huppertz A, Hamm B, Lembcke A. Individual selection of X-ray tube settings in computed tomography coronary angiography: Reliability of an automated software algorithm to maintain constant image quality. Eur J Radiol 2016; 85:963-71. [PMID: 27130057 DOI: 10.1016/j.ejrad.2016.03.004] [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: 02/10/2015] [Revised: 02/28/2016] [Accepted: 03/02/2016] [Indexed: 11/25/2022]
Abstract
OBJECTIVES To evaluate a software tool that claims to maintain a constant contrast-to-noise ratio (CNR) in high-pitch dual-source computed tomography coronary angiography (CTCA) by automatically selecting both X-ray tube voltage and current. METHODS A total of 302 patients (171 males; age 61±12years; body weight 82±17kg, body mass index 27.3±4.6kg/cm(2)) underwent CTCA with a topogram-based, automatic selection of both tube voltage and current using dedicated software with quality reference values of 100kV and 250mAs/rotation (i.e., standard values for an average adult weighing 75kg) and an injected iodine load of 222mg/kg. RESULTS The average radiation dose was estimated to be 1.02±0.64mSv. All data sets had adequate contrast enhancement. Average CNR in the aortic root, left ventricle, and left and right coronary artery was 15.7±4.5, 8.3±2.9, 16.1±4.3 and 15.3±3.9 respectively. Individual CNR values were independent of patients' body size and radiation dose. However, individual CNR values may vary considerably between subjects as reflected by interquartile ranges of 12.6-18.6, 6.2-9.9, 12.8-18.9 and 12.5-17.9 respectively. Moreover, average CNR values were significantly lower in males than females (15.1±4.1 vs. 16.6±11.7 and 7.9±2.7 vs. 8.9±3.0, 15.5±3.9 vs. 16.9±4.6 and 14.7±3.6 vs. 16.0±4.1 respectively). CONCLUSION A topogram-based automatic selection of X-ray tube settings in CTCA provides diagnostic image quality independent of patients' body size. Nevertheless, considerable variation of individual CNR values between patients and significant differences of CNR values between males and females occur which questions the reliability of this approach.
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Affiliation(s)
- Tahir Durmus
- Department of Radiology, Charité-Universitätsmedizin Berlin, Charité Campus Mitte, Berlin, Germany.
| | - Reny Luhur
- Department of Radiology, Charité-Universitätsmedizin Berlin, Charité Campus Mitte, Berlin, Germany
| | - Tareef Daqqaq
- Department of Radiology, Charité-Universitätsmedizin Berlin, Charité Campus Mitte, Berlin, Germany
| | | | - Gesine Knobloch
- Department of Radiology, Charité-Universitätsmedizin Berlin, Charité Campus Mitte, Berlin, Germany
| | | | - Bernd Hamm
- Department of Radiology, Charité-Universitätsmedizin Berlin, Charité Campus Mitte, Berlin, Germany
| | - Alexander Lembcke
- Department of Radiology, Charité-Universitätsmedizin Berlin, Charité Campus Mitte, Berlin, Germany
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Spearman JV, Schoepf UJ, Rottenkolber M, Driesser I, Canstein C, Thierfelder KM, Krazinski AW, De Cecco CN, Meinel FG. Effect of Automated Attenuation-based Tube Voltage Selection on Radiation Dose at CT: An Observational Study on a Global Scale. Radiology 2015; 279:167-74. [PMID: 26473641 DOI: 10.1148/radiol.2015141507] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
PURPOSE To evaluate the effect of automated tube voltage selection (ATVS) on radiation dose at computed tomography (CT) worldwide encompassing all body regions and types of CT examinations. MATERIALS AND METHODS No patient information was accessed; therefore, institutional review board approval was not sought. Data from 86 centers across the world were analyzed. All CT interactions were automatically collected and transmitted to the CT vendor during two 6-week periods immediately before and 2 weeks after implementation of ATVS. A total of 164 323 unique CT studies were analyzed. Studies were categorized by body region and type of examination. Tube voltage and volume CT dose index (CTDIvol) were compared between examinations performed with ATVS and those performed before ATVS implementation. Descriptive statistical methods and multilevel linear regression models were used for analysis. RESULTS Across all types of CT examinations and body regions, CTDIvol was 14.7% lower in examinations performed with ATVS (n = 30 313) than in those performed before ATVS implementation (n = 79 275). Relative reductions in mean CTDIvol were most notable for temporal bone CT (-56.1%), peripheral runoff CT angiography (-48.6%), CT of the paranasal sinus (-39.6%), cerebral or carotid CT angiography (-36.4%), coronary CT angiography (-25.1%), and head CT (-23.9%). An increase in mean CTDIvol was observed for renal stone protocols (26.2%) and thoracic or lumbar spine examinations (6.6%). In the multilevel model with fixed effects ATVS and examination type, and the interaction of these variables and the random effect country, a significant influence on CTDIvol for all fixed efects was revealed (ATVS, P = .0031; examination type, P < .0001; interaction term, P < .0001). CONCLUSION ATVS significantly reduces radiation dose across most, but not all, body regions and types of CT examinations.
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Affiliation(s)
- James V Spearman
- From the Division of Cardiovascular Imaging, Department of Radiology and Radiological Science (J.V.S., U.J.S., A.W.K., C.N.D.C., F.G.M.) and Division of Cardiology, Department of Medicine (U.J.S.), Medical University of South Carolina, 25 Courtenay Dr, MSC 226, Charleston, SC 29425; Medizinische Klinik und Poliklinik IV, Ludwig-Maximilians-Universität, Munich, Germany (M.R.); Healthcare Division, Computed Tomography, Siemens, Forchheim, Germany (I.D.); Siemens Medical Solutions USA, Malvern, Pa (C.C.); Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital, Munich, Germany (K.M.T., F.G.M.); and Department of Radiological Sciences, Oncology and Pathology, University of Rome "Sapienza"-Polo Pontino, Latina, Italy (C.N.D.C.)
| | - U Joseph Schoepf
- From the Division of Cardiovascular Imaging, Department of Radiology and Radiological Science (J.V.S., U.J.S., A.W.K., C.N.D.C., F.G.M.) and Division of Cardiology, Department of Medicine (U.J.S.), Medical University of South Carolina, 25 Courtenay Dr, MSC 226, Charleston, SC 29425; Medizinische Klinik und Poliklinik IV, Ludwig-Maximilians-Universität, Munich, Germany (M.R.); Healthcare Division, Computed Tomography, Siemens, Forchheim, Germany (I.D.); Siemens Medical Solutions USA, Malvern, Pa (C.C.); Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital, Munich, Germany (K.M.T., F.G.M.); and Department of Radiological Sciences, Oncology and Pathology, University of Rome "Sapienza"-Polo Pontino, Latina, Italy (C.N.D.C.)
| | - Marietta Rottenkolber
- From the Division of Cardiovascular Imaging, Department of Radiology and Radiological Science (J.V.S., U.J.S., A.W.K., C.N.D.C., F.G.M.) and Division of Cardiology, Department of Medicine (U.J.S.), Medical University of South Carolina, 25 Courtenay Dr, MSC 226, Charleston, SC 29425; Medizinische Klinik und Poliklinik IV, Ludwig-Maximilians-Universität, Munich, Germany (M.R.); Healthcare Division, Computed Tomography, Siemens, Forchheim, Germany (I.D.); Siemens Medical Solutions USA, Malvern, Pa (C.C.); Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital, Munich, Germany (K.M.T., F.G.M.); and Department of Radiological Sciences, Oncology and Pathology, University of Rome "Sapienza"-Polo Pontino, Latina, Italy (C.N.D.C.)
| | - Ivo Driesser
- From the Division of Cardiovascular Imaging, Department of Radiology and Radiological Science (J.V.S., U.J.S., A.W.K., C.N.D.C., F.G.M.) and Division of Cardiology, Department of Medicine (U.J.S.), Medical University of South Carolina, 25 Courtenay Dr, MSC 226, Charleston, SC 29425; Medizinische Klinik und Poliklinik IV, Ludwig-Maximilians-Universität, Munich, Germany (M.R.); Healthcare Division, Computed Tomography, Siemens, Forchheim, Germany (I.D.); Siemens Medical Solutions USA, Malvern, Pa (C.C.); Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital, Munich, Germany (K.M.T., F.G.M.); and Department of Radiological Sciences, Oncology and Pathology, University of Rome "Sapienza"-Polo Pontino, Latina, Italy (C.N.D.C.)
| | - Christian Canstein
- From the Division of Cardiovascular Imaging, Department of Radiology and Radiological Science (J.V.S., U.J.S., A.W.K., C.N.D.C., F.G.M.) and Division of Cardiology, Department of Medicine (U.J.S.), Medical University of South Carolina, 25 Courtenay Dr, MSC 226, Charleston, SC 29425; Medizinische Klinik und Poliklinik IV, Ludwig-Maximilians-Universität, Munich, Germany (M.R.); Healthcare Division, Computed Tomography, Siemens, Forchheim, Germany (I.D.); Siemens Medical Solutions USA, Malvern, Pa (C.C.); Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital, Munich, Germany (K.M.T., F.G.M.); and Department of Radiological Sciences, Oncology and Pathology, University of Rome "Sapienza"-Polo Pontino, Latina, Italy (C.N.D.C.)
| | - Kolja M Thierfelder
- From the Division of Cardiovascular Imaging, Department of Radiology and Radiological Science (J.V.S., U.J.S., A.W.K., C.N.D.C., F.G.M.) and Division of Cardiology, Department of Medicine (U.J.S.), Medical University of South Carolina, 25 Courtenay Dr, MSC 226, Charleston, SC 29425; Medizinische Klinik und Poliklinik IV, Ludwig-Maximilians-Universität, Munich, Germany (M.R.); Healthcare Division, Computed Tomography, Siemens, Forchheim, Germany (I.D.); Siemens Medical Solutions USA, Malvern, Pa (C.C.); Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital, Munich, Germany (K.M.T., F.G.M.); and Department of Radiological Sciences, Oncology and Pathology, University of Rome "Sapienza"-Polo Pontino, Latina, Italy (C.N.D.C.)
| | - Aleksander W Krazinski
- From the Division of Cardiovascular Imaging, Department of Radiology and Radiological Science (J.V.S., U.J.S., A.W.K., C.N.D.C., F.G.M.) and Division of Cardiology, Department of Medicine (U.J.S.), Medical University of South Carolina, 25 Courtenay Dr, MSC 226, Charleston, SC 29425; Medizinische Klinik und Poliklinik IV, Ludwig-Maximilians-Universität, Munich, Germany (M.R.); Healthcare Division, Computed Tomography, Siemens, Forchheim, Germany (I.D.); Siemens Medical Solutions USA, Malvern, Pa (C.C.); Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital, Munich, Germany (K.M.T., F.G.M.); and Department of Radiological Sciences, Oncology and Pathology, University of Rome "Sapienza"-Polo Pontino, Latina, Italy (C.N.D.C.)
| | - Carlo N De Cecco
- From the Division of Cardiovascular Imaging, Department of Radiology and Radiological Science (J.V.S., U.J.S., A.W.K., C.N.D.C., F.G.M.) and Division of Cardiology, Department of Medicine (U.J.S.), Medical University of South Carolina, 25 Courtenay Dr, MSC 226, Charleston, SC 29425; Medizinische Klinik und Poliklinik IV, Ludwig-Maximilians-Universität, Munich, Germany (M.R.); Healthcare Division, Computed Tomography, Siemens, Forchheim, Germany (I.D.); Siemens Medical Solutions USA, Malvern, Pa (C.C.); Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital, Munich, Germany (K.M.T., F.G.M.); and Department of Radiological Sciences, Oncology and Pathology, University of Rome "Sapienza"-Polo Pontino, Latina, Italy (C.N.D.C.)
| | - Felix G Meinel
- From the Division of Cardiovascular Imaging, Department of Radiology and Radiological Science (J.V.S., U.J.S., A.W.K., C.N.D.C., F.G.M.) and Division of Cardiology, Department of Medicine (U.J.S.), Medical University of South Carolina, 25 Courtenay Dr, MSC 226, Charleston, SC 29425; Medizinische Klinik und Poliklinik IV, Ludwig-Maximilians-Universität, Munich, Germany (M.R.); Healthcare Division, Computed Tomography, Siemens, Forchheim, Germany (I.D.); Siemens Medical Solutions USA, Malvern, Pa (C.C.); Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital, Munich, Germany (K.M.T., F.G.M.); and Department of Radiological Sciences, Oncology and Pathology, University of Rome "Sapienza"-Polo Pontino, Latina, Italy (C.N.D.C.)
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Celeng C, Vadvala H, Puchner S, Pursnani A, Sharma U, Kovacs A, Maurovich-Horvat P, Hoffmann U, Ghoshhajra B. Defining the optimal systolic phase targets using absolute delay time for reconstructions in dual-source coronary CT angiography. Int J Cardiovasc Imaging 2015; 32:91-100. [PMID: 26335369 DOI: 10.1007/s10554-015-0755-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/30/2015] [Accepted: 08/26/2015] [Indexed: 10/23/2022]
Abstract
To define the optimal systolic phase for dual-source computed tomography angiography using an absolute reconstruction delay time after the R-R interval based on the coronary artery motion, we analyzed images reconstructed between 200 and 420 miliseconds (ms) after the R wave at 20 ms increments in 21 patients. Based on the American Heart Association coronary segmentation guidelines, the origin of six coronary artery landmarks (RCA, AM1, PDA, LM, OM1, and D2) were selected to calculate the coronary artery motion velocity. The velocity of the given landmark was defined as the quotient of the route and the length of the time interval. The x, y and z-coordinates of the selected landmark were recorded, and were used for the calculation of the 3D route of coronary artery motion by using a specific equation. Differences in velocities were assessed by analysis of variance for repeated measures; Bonferroni post hoc tests were used for multiple pair wise comparisons. 1488 landmarks were measured (6 locations at 12 systolic time points) in 21 patients and were analyzed. The mean values of the minimum velocities were calculated separately for each heart rate group (i.e. <65; 65-80; and >80 bpm). The mean lowest coronary artery velocities in each segment occurred in the middle period of each time interval of the acquired systolic phase i.e. 280-340 ms. No differences were found in the minimal coronary artery velocities between the three HR groups, with the exception of the AM1 branch (p = 0.00495) between <65 and >80 bpm (p = 0.03), and at HRs of 65-80 versus >80 bpm (p = 0.006). During an absolute delay of 200-420 ms after the R-wave, the ideal reconstruction interval varies significantly among coronary artery segments. Decreased velocities occur between 280 to 340 ms. Therefore a narrow range of systolic intervals, rather than a single phase, should be acquired.
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Affiliation(s)
- Csilla Celeng
- Cardiovascular Imaging, Cardiac MR PET CT Program, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, 55 Fruit Street, Boston, MA, 02114, USA. .,MTA-SE Cardiovascular Imaging Research Group, Heart and Vascular Center, Semmelweis University, 68 Varosmajor Street, 1122, Budapest, Hungary.
| | - Harshna Vadvala
- Cardiovascular Imaging, Cardiac MR PET CT Program, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, 55 Fruit Street, Boston, MA, 02114, USA.
| | - Stefan Puchner
- Cardiovascular Imaging, Cardiac MR PET CT Program, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, 55 Fruit Street, Boston, MA, 02114, USA.
| | - Amit Pursnani
- Cardiovascular Imaging, Cardiac MR PET CT Program, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, 55 Fruit Street, Boston, MA, 02114, USA.
| | - Umesh Sharma
- Cardiovascular Imaging, Cardiac MR PET CT Program, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, 55 Fruit Street, Boston, MA, 02114, USA.
| | - Attila Kovacs
- MTA-SE Cardiovascular Imaging Research Group, Heart and Vascular Center, Semmelweis University, 68 Varosmajor Street, 1122, Budapest, Hungary.
| | - Pâl Maurovich-Horvat
- MTA-SE Cardiovascular Imaging Research Group, Heart and Vascular Center, Semmelweis University, 68 Varosmajor Street, 1122, Budapest, Hungary.
| | - Udo Hoffmann
- Cardiovascular Imaging, Cardiac MR PET CT Program, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, 55 Fruit Street, Boston, MA, 02114, USA.
| | - Brian Ghoshhajra
- Cardiovascular Imaging, Cardiac MR PET CT Program, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, 55 Fruit Street, Boston, MA, 02114, USA.
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Yin WH, Lu B, Gao JB, Li PL, Sun K, Wu ZF, Yang WJ, Zhang XQ, Zheng MW, McQuiston AD, Meinel FG, Schoepf UJ. Effect of reduced x-ray tube voltage, low iodine concentration contrast medium, and sinogram-affirmed iterative reconstruction on image quality and radiation dose at coronary CT angiography: results of the prospective multicenter REALISE trial. J Cardiovasc Comput Tomogr 2015; 9:215-24. [PMID: 25843243 DOI: 10.1016/j.jcct.2015.01.010] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/19/2014] [Revised: 01/02/2015] [Accepted: 01/11/2015] [Indexed: 11/30/2022]
Abstract
BACKGROUND Both low tube voltage and sinogram-affirmed iterative reconstruction (IR) techniques hold promise to decrease radiation dose at coronary CT angiography (CCTA). The increased iodine contrast at low tube voltage allows for minimizing iodine load. OBJECTIVE To assess the effect of reduced x-ray tube voltage, low iodine concentration contrast medium and IR on image quality and radiation dose at CCTA. METHODS Two hundred thirty-one consecutive patients with suspected coronary artery disease were enrolled in this prospective, multicenter trial and randomized to 1 of 2 dual-source CCTA protocols: 120-kVp with 370 mgI/mL iopromide or iopamidol (n = 116; 44 women; 55.3 ± 9.8 years) or 100 kVp with 270 mgI/mL iodixanol (n = 115; 48 women; 54.2 ± 10.4 years). Reconstruction was performed with filtered back projection and IR. Attenuation, image noise, signal-to-noise ratio, and contrast-to-noise ratio were measured and image quality scored. Size-specific dose estimates and effective doses were calculated. RESULTS There were no significant differences in mean arterial attenuation (406.6 ± 76.7 vs 409.7 ± 65.2 Hounsfield units; P = .739), image noise (18.7 ± 3.8 vs 17.9 ± 3.4 Hounsfield units; P = .138), signal-to-noise ratio (22.5 ± 5.4 vs 23.7 ± 6.1; P = .126), contrast-to-noise ratio (17.5 ± 5.5 vs 18.3 ± 6.1; P = .286), or image quality scores (4.1 ± 0.9 vs 4.0 ± 0.9; P > .05) between 120-kVp filtered back projection-reconstructed and 100-kVp IR-reconstructed series. Mean iodine dose was 26.5% lower (18.3 ± 0.5 vs 24.9 ± 0.9 g; P < .0001), mean size-specific dose estimate was 35.1% lower (17.9 ± 6.6 vs 27.5 ± 8.2 mGy; P < .0001), and effective dose was 34.9% lower (2.3 ± 1.0 vs 3.5 ± 1.1 mSv; P < .0001) with the 100 kVp compared with the 120-kVp protocol, respectively. CONCLUSION Using low x-ray tube voltage and IR allows for decreasing the iodine load and effective radiation dose at CCTA while maintaining image quality.
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Affiliation(s)
- Wei-Hua Yin
- Department of Radiology, State Key Laboratory of Cardiovascular Disease, Fu Wai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, #167 Bei-Li-Shi Street, Xi-Cheng District, Beijing 100037, People's Republic of China
| | - Bin Lu
- Department of Radiology, State Key Laboratory of Cardiovascular Disease, Fu Wai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, #167 Bei-Li-Shi Street, Xi-Cheng District, Beijing 100037, People's Republic of China.
| | - Jian-Bo Gao
- Department of Radiology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China
| | - Pei-Ling Li
- Department of Radiology, The First Affiliated Hospital of China Medical University, Shenyang, Liaoning, China
| | - Kai Sun
- Department of Radiology, Baotou Central Hospital, Baotou, Inner Mongolia, China
| | - Zhi-Feng Wu
- Department of Radiology, Shanxi DAYI Hospital, Taiyuan, Shanxi, China
| | - Wen-Jie Yang
- Department of Radiology, Rui Jin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Xiao-Qin Zhang
- Department of Radiology, Inner Mongolia People's Hospital, Huhehaote, Inner Mongolia, China
| | - Min-Wen Zheng
- Department of Radiology, Xijing Hospital, Fourth Military Medical University. Xi'an, Shaanxi, China
| | - Andrew D McQuiston
- Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC, USA
| | - Felix G Meinel
- Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC, USA
| | - Uwe Joseph Schoepf
- Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC, USA; Division of Cardiology, Department of Medicine, Medical University of South Carolina, Charleston, SC, USA
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26
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Vadvala H, Kim P, Mayrhofer T, Pianykh O, Kalra M, Hoffmann U, Ghoshhajra B. Coronary CTA using scout-based automated tube potential and current selection algorithm, with breast displacement results in lower radiation exposure in females compared to males. Cardiovasc Diagn Ther 2015; 4:470-9. [PMID: 25610804 DOI: 10.3978/j.issn.2223-3652.2014.12.07] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2014] [Accepted: 12/12/2014] [Indexed: 11/14/2022]
Abstract
PURPOSE To evaluate the effect of automatic tube potential selection and automatic exposure control combined with female breast displacement during coronary computed tomography angiography (CCTA) on radiation exposure in women versus men of the same body size. MATERIALS AND METHODS Consecutive clinical exams between January 2012 and July 2013 at an academic medical center were retrospectively analyzed. All examinations were performed using ECG-gating, automated tube potential, and tube current selection algorithm (APS-AEC) with breast displacement in females. Cohorts were stratified by sex and standard World Health Organization body mass index (BMI) ranges. CT dose index volume (CTDIvol), dose length product (DLP) median effective dose (ED), and size specific dose estimate (SSDE) were recorded. Univariable and multivariable regression analyses were performed to evaluate the effect of gender on radiation exposure per BMI. RESULTS A total of 726 exams were included, 343 (47%) were females; mean BMI was similar by gender (28.6±6.9 kg/m(2) females vs. 29.2±6.3 kg/m(2) males; P=0.168). Median ED was 2.3 mSv (1.4-5.2) for females and 3.6 (2.5-5.9) for males (P<0.001). Females were exposed to less radiation by a difference in median ED of -1.3 mSv, CTDIvol -4.1 mGy, and SSDE -6.8 mGy (all P<0.001). After adjusting for BMI, patient characteristics, and gating mode, females exposure was lower by a median ED of -0.7 mSv, CTDIvol -2.3 mGy, and SSDE -3.15 mGy, respectively (all P<0.01). CONCLUSIONS We observed a difference in radiation exposure to patients undergoing CCTA with the combined use of AEC-APS and breast displacement in female patients as compared to their BMI-matched male counterparts, with female patients receiving one third less exposure.
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Affiliation(s)
- Harshna Vadvala
- Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA
| | - Phillip Kim
- Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA
| | - Thomas Mayrhofer
- Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA
| | - Oleg Pianykh
- Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA
| | - Mannudeep Kalra
- Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA
| | - Udo Hoffmann
- Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA
| | - Brian Ghoshhajra
- Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA
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Lim J, Park EA, Lee W, Shim H, Chung JW. Image quality and radiation reduction of 320-row area detector CT coronary angiography with optimal tube voltage selection and an automatic exposure control system: comparison with body mass index-adapted protocol. Int J Cardiovasc Imaging 2015; 31 Suppl 1:23-30. [DOI: 10.1007/s10554-015-0594-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/26/2014] [Accepted: 01/14/2015] [Indexed: 10/24/2022]
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Adaptation of contrast injection protocol to tube potential for cardiovascular CT. AJR Am J Roentgenol 2014; 203:1181-91. [PMID: 25415695 DOI: 10.2214/ajr.13.12013] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
OBJECTIVE The purpose of this study was to investigate and validate adaptation of a cardiovascular CT angiography contrast injection protocol for lower tube potential. MATERIALS AND METHODS Eighty-three patients evaluated for thoracic aortic disease with a 256-MDCT scanner were imaged at 120 kV (group 1) or 100 kV (group 2) with the same contrast protocol (90 mL iopromide 370 mg I/mL at 3.5 mL/s). A pharmacokinetic model was validated and used to simulate aortic attenuation in group 2 patients with 20%, 33%, and 44% reduction in contrast volume. A 44% volume reduction was applied to 50 additional patients who underwent imaging at 100 kV (group 3). Patient characteristics, scanning and radiation parameters, and objective and subjective image indexes were compared among groups. RESULTS Group 2 patients had higher mean aortic blood attenuation (399±61 HU) than group 1 patients (281±48 HU) (p<0.001) but similar image noise. Group 3 and group 1 patients had similar mean aortic attenuation and noise. Subjective assessment of image quality indicated that group 3 and group 1 had comparable percentages of images with good or excellent diagnostic confidence scores (reader 1, 98% vs 96%; reader 2, 96% vs 96%). CONCLUSION Lower tube potential (100 kV) for cardiothoracic CT could be accompanied by a 44% reduction in contrast volume with satisfactory aortic blood-pool attenuation in most patients. More personalized adaptation of the contrast protocol that takes into account patient characteristics and tube potential is necessary to ensure sufficient contrast enhancement for all patients.
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Low Radiation Coronary CT. CURRENT CARDIOVASCULAR IMAGING REPORTS 2014. [DOI: 10.1007/s12410-014-9284-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Krazinski AW, Meinel FG, Schoepf UJ, Silverman JR, Canstein C, De Cecco CN, Geyer LL. Reduced radiation dose and improved image quality at cardiovascular CT angiography by automated attenuation-based tube voltage selection: intra-individual comparison. Eur Radiol 2014; 24:2677-84. [PMID: 25052076 DOI: 10.1007/s00330-014-3312-9] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2014] [Revised: 05/14/2014] [Accepted: 07/03/2014] [Indexed: 11/27/2022]
Abstract
OBJECTIVES To evaluate the effect of automated tube voltage selection on radiation dose and image quality at cardiovascular CT angiography (CTA). METHODS We retrospectively analysed paired studies in 72 patients (41 male, 60.5 ± 16.5 years), who had undergone CTA acquisitions of the heart or aorta both before and after the implementation of an automated x-ray tube voltage selection algorithm (ATVS). All other parameters were kept identical between the two acquisitions. Subjective image quality (IQ) was rated and objective IQ was measured by image noise, signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR) and figure of merit (FOM). Image quality parameters and effective dose were compared between acquisitions. RESULTS Overall subjective image quality improved with the percentage of cases scored as adequate or higher increasing from 79 % to 92 % after implementation of ATVS (P = 0.03). SNR (14.1 ± 5.9, 15.7 ± 6.1, P = 0.009), CNR (11.6 ± 5.3, 13.2 ± 5.6, P = 0.011), and FOM (19.9 ± 23.3, 43.8 ± 51.1, P < 0.001) were significantly higher after implementation of ATVS. Mean image noise (24.1 ± 8.4 HU, 22.7 ± 7.1 HU, P = 0.048) and mean effective dose (10.6 ± 5.9 mSv, 8.8 ± 5.0 mSv, P = 0.003) were significantly lower after implementation of ATVS. CONCLUSIONS Automated tube voltage selection can operator-independently optimize cardiovascular CTA image acquisition parameters with improved image quality at reduced dose. KEY POINTS • Automatic tube voltage selection optimizes tube voltage for each individual patient. • In this population, overall radiation dose decreased while image quality improved. • This tool may become valuable for improving dose/quality ratio.
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Affiliation(s)
- Aleksander W Krazinski
- Department of Radiology and Radiological Science, Medical University of South Carolina, Ashley River Tower, MSC 226 25 Courtenay Drive, Charleston, SC, 29425, USA
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Pursnani A, Lee A, Mayrhofer T, Panagia M, Sharma U, Abbara S, Hoffmann U, Ghoshhajra BB. Feasibility of a radiation dose conserving CT protocol for myocardial function assessment. Br J Radiol 2014; 87:20130755. [PMID: 24884727 DOI: 10.1259/bjr.20130755] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
OBJECTIVE Assessment of myocardial function can be performed at higher noise levels than necessary for coronary arterial evaluation. We evaluated image quality and radiation exposure of a dose-conserving function-only acquisition vs retrospectively electrocardiogram(ECG)-gated coronary CTA with automatic tube current modulation. METHODS Of 26 patients who underwent clinically indicated coronary CTA for coronary and function evaluation, 13 (Group I) underwent prospectively ECG-triggered coronary CTA, followed by low-dose retrospectively ECG-gated scan for function (128-slice dual-source, 80 kVp; reference tube current, 100 mA; 8-mm-thick multiplanar reformatted reconstructions) performed either immediately (n = 6) or after 5- to 10-min delay for infarct assessment (n = 7). 13 corresponding controls (Group II) underwent retrospectively ECG-gated protocols (automatic tube potential selection with CARE kV/CARE Dose 4D; Siemens Healthcare, Forchheim, Germany) with aggressive dose modulation. Image quality assessment was performed on the six Group I subjects who underwent early post-contrast dedicated function scan and corresponding controls. Radiation exposure was based on dose-length product. RESULTS Contrast-to-noise ratio (CNR) was preserved throughout the cardiac cycle in Group I and varied according to dose modulation in Group II. Visual image quality indices were similar during end systole but were better in Group II at end diastole. Although the total radiation exposure was equivalent in Group I and Group II (284 vs 280 mGy cm), the median radiation exposure associated with only the dedicated function scan was 138 mGy cm (interquartile range, 116-203 mGy cm). CONCLUSION A low-dose retrospective ECG-gated protocol permits assessment of myocardial function at a median radiation exposure of 138 mGy cm and offers more consistent multiphase CNR vs traditional ECG-modulation protocols. This is useful for pure functional evaluation or as an adjunct to single-phase scan modes. ADVANCES IN KNOWLEDGE Radiation exposure can be limited with a tailored myocardial function CT protocol while maintaining preserved images.
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Affiliation(s)
- A Pursnani
- Cardiac MR PET CT Program, Division of Cardiology and Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
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Lee AM, Engel LC, Hui GC, Liew G, Ferencik M, Sidhu MS, Hoffmann U, Ghoshhajra BB. Coronary computed tomography angiography at 140 kV versus 120 kV: assessment of image quality and radiation exposure in overweight and moderately obese patients. Acta Radiol 2014; 55:554-62. [PMID: 24031049 DOI: 10.1177/0284185113502745] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Although a tube potential of 140 kV is available on most computed tomography (CT) scanners, its incremental diagnostic value versus 120 kV has been controversial. PURPOSE To retrospectively evaluate the image quality and radiation exposure of cardiac computed tomography angiography (CCTA) performed at 140 kV in comparison to CCTA at 120 kV in overweight and moderately obese patients. MATERIAL AND METHODS Eighty-eight patients who were referred for CCTA between January 2010 and May 2012 were included. Forty-four patients who were overweight or moderately obese (body mass index [BMI], 25-35 kg/m(2)) underwent CCTA with dual-source CT (DSCT) scanner at 140 kV. Forty-four match controls who underwent CCTA with DSCT at 120 kV were identified per BMI, average heart rate, scan indication, and scan acquisition mode. All scans were performed per routine protocols with direct physician supervision. Quantitative image metrics (CT attenuation, image noise, contrast-to-noise ratio [CNR], and signal-to-noise ratio [SNR] of left main [LM] and proximal right coronary artery [RCA]) were assessed. Effective radiation dose was compared between the two groups. RESULTS Overall, all scans were diagnostic without any non-evaluable coronary segment per clinical report. 140 kV had a lower attenuation and image noise versus 120 kV (P<0.01). Both SNR and CNR of proximal coronary arteries were similar between 140 kV and 120 kV (SNR, LM P=0.93, RCA P=0.62; CNR, LM P=0.57, RCA P=0.77). 140 kV was associated with a 35.3% increase in effective radiation dose as compared with 120 kV (5.1 [3.6-8.2] vs. 3.3 [2.0-5.1] mSv, respectively; P<0.01). CONCLUSION 140 kV CCTA resulted in similar image quality but a higher effective radiation dose in comparison to 120 kV CCTA. Therefore, in overweight and moderately obese patients, a tube potential of 120 kV may be sufficient for CCTA with diagnostic image quality.
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Affiliation(s)
- Ashley M Lee
- Cardiac MR PET CT Program, Massachusetts General Hospital and Harvard Medical School, Department of Radiology and Division of Cardiology, Boston, MA, USA
| | - Leif-Christopher Engel
- Cardiac MR PET CT Program, Massachusetts General Hospital and Harvard Medical School, Department of Radiology and Division of Cardiology, Boston, MA, USA
| | - Gladwin C Hui
- Cardiac MR PET CT Program, Massachusetts General Hospital and Harvard Medical School, Department of Radiology and Division of Cardiology, Boston, MA, USA
| | - Gary Liew
- Cardiac MR PET CT Program, Massachusetts General Hospital and Harvard Medical School, Department of Radiology and Division of Cardiology, Boston, MA, USA
| | - Maros Ferencik
- Cardiac MR PET CT Program, Massachusetts General Hospital and Harvard Medical School, Department of Radiology and Division of Cardiology, Boston, MA, USA
| | - Manavjot S Sidhu
- Cardiac MR PET CT Program, Massachusetts General Hospital and Harvard Medical School, Department of Radiology and Division of Cardiology, Boston, MA, USA
| | - Udo Hoffmann
- Cardiac MR PET CT Program, Massachusetts General Hospital and Harvard Medical School, Department of Radiology and Division of Cardiology, Boston, MA, USA
| | - Brian B Ghoshhajra
- Cardiac MR PET CT Program, Massachusetts General Hospital and Harvard Medical School, Department of Radiology and Division of Cardiology, Boston, MA, USA
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Frellesen C, Stock W, Kerl JM, Lehnert T, Wichmann JL, Nau C, Geiger E, Wutzler S, Beeres M, Schulz B, Bodelle B, Ackermann H, Vogl TJ, Bauer RW. Topogram-based automated selection of the tube potential and current in thoraco-abdominal trauma CT - a comparison to fixed kV with mAs modulation alone. Eur Radiol 2014; 24:1725-34. [PMID: 24816940 DOI: 10.1007/s00330-014-3197-7] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2013] [Revised: 03/15/2014] [Accepted: 04/22/2014] [Indexed: 11/26/2022]
Abstract
OBJECTIVE To investigate the impact of automated attenuation-based tube potential selection on image quality and exposure parameters in polytrauma patients undergoing contrast-enhanced thoraco-abdominal CT. METHODS One hundred patients were examined on a 16-slice device at 120 kV with 190 ref.mAs and automated mA modulation only. Another 100 patients underwent 128-slice CT with automated mA modulation and topogram-based automated tube potential selection (autokV) at 100, 120 or 140 kV. Volume CT dose index (CTDI(vol)), dose-length product (DLP), body diameters, noise, signal-to-noise ratio (SNR) and subjective image quality were compared. RESULTS In the autokV group, 100 kV was automatically selected in 82 patients, 120 kV in 12 patients and 140 kV in 6 patients. Patient diameters increased with higher kV settings. The median CTDI(vol) (8.3 vs. 12.4 mGy; -33%) and DLP (594 vs. 909 mGy cm; -35%) in the entire autokV group were significantly lower than in the group with fixed 120 kV (p < 0.05 for both). Image quality remained at a constantly high level at any selected kV level. CONCLUSION Topogram-based automated selection of the tube potential allows for significant dose savings in thoraco-abdominal trauma CT while image quality remains at a constantly high level. KEY POINTS • Automated kV selection in thoraco-abdominal trauma CT results in significant dose savings • Most patients benefit from a 100-kV protocol with relevant DLP reduction • Constantly good image quality is ensured • Image quality benefits from higher kV when arms are positioned downward.
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Affiliation(s)
- Claudia Frellesen
- Department of Diagnostic and Interventional Radiology, Clinic of the Goethe University, Theodor-Stern-Kai 7, 60590, Frankfurt, Germany
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Ultra-low contrast computed tomographic angiography (CTA) with 20-mL total dose for transcatheter aortic valve implantation (TAVI) planning. J Comput Assist Tomogr 2014; 38:105-9. [PMID: 24378883 DOI: 10.1097/rct.0b013e3182a14358] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Transcatheter aortic valve implantation workup includes assessment of the aorta and the iliofemoral arteries by computed tomographic angiography. An important group of transcatheter aortic valve implantation candidates have severe renal failure. We tested a novel computed tomographic angiography protocol (128-detector-row dual-source scanner, high-pitch helical mode) with ultralow contrast volume (20 mL) in 8 patients, compared with 8 controls. Contrast-to-noise ratio and subjective image quality, albeit lower than in the controls, were suitable for interpretation in the ultralow contrast volume group throughout all measured locations.
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Radiation dose reduction in pediatric cardiac computed tomography: experience from a tertiary medical center. Pediatr Cardiol 2014; 35:171-9. [PMID: 23872908 DOI: 10.1007/s00246-013-0758-5] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/19/2013] [Accepted: 06/20/2013] [Indexed: 10/26/2022]
Abstract
Cardiac CT angiography (cCTA) has become an established method for the assessment of congenital heart disease. However, the potential harmful effects of ionizing radiation must be considered, particularly in younger, more radiosensitive patients. In this study, we sought to assess the temporal change in radiation doses from pediatric cCTA during an 8-year period at a tertiary medical center. This retrospective study included all patients ≤18 years old who were referred to electrocardiography (ECG)-gated cCTA for the assessment of congenital heart disease or inflammatory disease (Kawasaki disease) from November 2004 to September 2012. During the study period, 95 patients were scanned using 3 different scanner models-64-slice multidetector CT (64-MDCT) and first- (64-DSCT) and second-generation (128-DSCT) dual-source CT-and 3 scan protocols-retrospective ECG-gated helical scanning (RG), prospective ECG-triggered axial scanning (PT), or prospective ECG-triggered high-pitch helical scanning (HPH). Effective dose (ED) was calculated with the dose length product method with a conversion factor (k) adjusted for age. ED was then compared among scan protocols. Image quality was extracted from clinical cCTA reports when available. Overall, 94 % of scans were diagnostic (80 % for 64-slice MDCT, 93 % for 64-slice DSCT, and 97 % for 128-slice DSCT).With 128-DSCT, median ED (1.0 [range 0.6-2.0] mSv) decreased by 85.8 % and 66.8 % compared with 64-MDCT (6.8 [range 2.9-13.6] mSv) and 64-DSCT (2.9 [range 0.9-4.1] mSv), respectively. With HPH, median ED (0.9 [range 0.6-1.8] mSv) decreased by 59.4 % and 85.4 % compared with PT (2.2 [range 0.9-3.4] mSv) and RG (6.1 [range 2.5-10.6] mSv). cCTA can now be obtained at very low radiation doses in pediatric patients using the latest dual-source CT technology in combination with prospective ECG-triggered HPH acquisition.
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Automated attenuation-based selection of tube voltage and tube current for coronary CT angiography: reduction of radiation exposure versus a BMI-based strategy with an expert investigator. J Cardiovasc Comput Tomogr 2013; 7:303-10. [PMID: 24268117 DOI: 10.1016/j.jcct.2013.08.010] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/29/2013] [Revised: 06/29/2013] [Accepted: 08/16/2013] [Indexed: 11/24/2022]
Abstract
BACKGROUND Recently developed automated algorithms use the topogram and the corresponding attenuation information before coronary CT angiography (CTA) to allow for an individualized anatomic-based selection of tube current (mAs) and voltage (kV). OBJECTIVES The value of these algorithms in reducing the associated radiation exposure was evaluated. METHODS One hundred patients underwent coronary CTA with dual-source CT with prospectively electrocardiogram-triggered axial data acquisition. In all patients, tube parameters (current and voltage) were suggested by both an experienced investigator according to the patient's body mass index (BMI; calculated as weight divided by height squared; kg/m(2)) and by an automated software according to attenuation values of the initial topogram. The first 50 consecutive patients (group 1) underwent coronary CTA with dual-source CT with tube parameters suggested by the experienced investigator (BMI-based tube parameters), whereas in another 50 consecutive patients (group 2) CT data acquisition was performed with tube settings of the automated software. Subsequently, subjective image quality (4-point rating score from 0 = nondiagnostic to 3 = excellent image quality), image noise (SD of CT number within the aortic root), as well as signal- and contrast-to-noise ratios and mean effective radiation doses, were compared between both groups. RESULTS Both groups showed comparable image quality parameters (group 1 vs 2: noise, 28.1 ± 6.0 HU vs 29.9 ± 5.4 HU, P = .12; signal-to-noise ratio, 16.4 ± 3.9 vs 16.8 ± 4.1, P = .54; contrast-to-noise ratio, 18.6 ± 4.1 vs 19.2 ± 4.3, P = .49; 4-point rating score, 2.8 ± 0.3 vs 2.9 ± 0.3, P = .81). Tube voltage, current, and mean effective radiation dose for groups 1 and 2 were 111 ± 12 kV and 108 ± 12 kV (P = .18), 361 ± 32 mAs and 320 ± 48 mAs (P < .001), and 2.3 mSv (25th; 75th percentile, 1.5; 2.8 mSv) and 1.4 mSv (25th; 75th percentile, 1.1; 1.9 mSv) (P < .001), respectively. CONCLUSIONS Automated attenuation-based selections of individualized tube parameters are superior to BMI-based selections with expert oversight and show a potential for reduction of radiation exposure in coronary CTA, and image quality is maintained.
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Engel LC, Lee AM, Seifarth H, Sidhu MS, Brady TJ, Hoffmann U, Ghoshhajra BB. Weekly dose reports: the effects of a continuous quality improvement initiative on coronary computed tomography angiography radiation doses at a tertiary medical center. Acad Radiol 2013; 20:1015-23. [PMID: 23830607 DOI: 10.1016/j.acra.2013.04.012] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2012] [Revised: 04/14/2013] [Accepted: 04/30/2013] [Indexed: 01/04/2023]
Abstract
RATIONALE AND OBJECTIVES Numerous protocols have been developed to reduce cardiac computed tomography angiography (cCTA) radiation dose while maintaining image quality. However, cCTA practice is highly dependent on physician and technologist experience and education. In this study, we sought to evaluate the incremental value of real-time feedback via weekly dose reports on a busy cCTA service. MATERIALS AND METHODS This time series analysis consisted of 450 consecutive patients whom underwent physician-supervised cCTA for clinically indicated native coronary evaluation between April 2011 and January 2013, with 150 patients before the initiation of weekly dose report (preintervention period: April-September 2011) and 150 patients after the initiation (postintervention period: September 2011-February 2012). To assess whether overall dose reductions were maintained over time, results were compared to a late control group consisting of 150 consecutive cCTA exams, which were performed after the study (September 2012-January 2013). Patient characteristics and effective radiation were recorded and compared. RESULTS Total radiation dose was significantly lower in the postintervention period (3.4 mSv [1.7-5.7] and in the late control group (3.3 mSv [2.0-5.3] versus the preintervention period (4.1 mSv [2.1-6.6] (P = .005). The proportion of high-dose outliers was also decreased in the postintervention period and late control period (exams <10 mSv were 88.0% preintervention vs. 97.3% postintervention vs. 95.3% late control; exams <15 mSv were 98.0% preintervention vs. 100.0% postintervention vs. 98.7% late control; exams <20.0 mSv were 98.7% preintervention vs. 100.0% postintervention vs. 100.0% late control). CONCLUSION Weekly dose report feedback of site radiation doses to patients undergoing physician-supervised cCTA resulted in significant overall dose reduction and reduction of high-dose outliers. Overall dose reductions were maintained beyond the initial study period.
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Affiliation(s)
- Leif-Christopher Engel
- Cardiac MR PET CT Program, Department of Radiology and Division of Cardiology, Massachusetts General Hospital and Harvard Medical School, 165 Cambridge St., Suite 400, Boston, MA 02114, USA
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Lee AM, Beaudoin J, Thai WE, Wai B, Hui GC, Sidhu MS, Engel LC, Abbara S, Hoffmann U, Ghoshhajra BB. Feasibility of aortic valve assessment with low dose prospectively triggered adaptive systolic (PTAS) cardiac computed tomography angiography. BMC Res Notes 2013; 6:158. [PMID: 23602055 PMCID: PMC3640955 DOI: 10.1186/1756-0500-6-158] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2013] [Accepted: 04/12/2013] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Cardiac computed tomography angiography (CTA) is feasible for aortic valve evaluation, but retrospective gated protocols required high radiation doses for aortic valve assessment. A prospectively triggered adaptive systolic (PTAS) cardiac CT protocol was recently described in arrhythmia using second-generation dual-source CT. In this study, we sought to evaluate the feasibility of PTAS CTA to assess the aortic valve at a low radiation dose. FINDINGS A retrospective cohort of 29 consecutive patients whom underwent PTAS protocols for clinical indications other than aortic valve assessment and whom also received echocardiography within 2 months of CT, was identified. Images were reviewed for aortic valve morphology (tricuspid/bicuspid/prosthetic) and stenosis (AS) by experienced blinded readers. Accuracy versus echocardiography and radiation doses were assessed. CONCLUSIONS PTAS CTA protocols using second-generation dual-source CT for aortic valve evaluation are feasible at low doses. This protocol should be investigated further in larger cohorts.
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Lee AM, Beaudoin J, Engel LC, Sidhu MS, Abbara S, Brady TJ, Hoffmann U, Ghoshhajra BB. Assessment of image quality and radiation dose of prospectively ECG-triggered adaptive dual-source coronary computed tomography angiography (cCTA) with arrhythmia rejection algorithm in systole versus diastole: a retrospective cohort study. Int J Cardiovasc Imaging 2013; 29:1361-70. [DOI: 10.1007/s10554-013-0208-8] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/16/2013] [Accepted: 03/15/2013] [Indexed: 11/30/2022]
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Chen MY, Shanbhag SM, Arai AE. Submillisievert median radiation dose for coronary angiography with a second-generation 320-detector row CT scanner in 107 consecutive patients. Radiology 2013; 267:76-85. [PMID: 23340461 DOI: 10.1148/radiol.13122621] [Citation(s) in RCA: 129] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
PURPOSE To (a) use a new second-generation wide-volume 320-detector row computed tomographic (CT) scanner to explore optimization of radiation exposure in coronary CT angiography in an unselected and consecutive cohort of patients referred for clinical purposes and (b) compare estimated radiation exposure and image quality with that from a cohort of similar patients who underwent imaging with a previous first-generation CT system. MATERIALS AND METHODS The study was approved by the institutional review board, and all subjects provided written consent. Coronary CT angiography was performed in 107 consecutive patients with a new second-generation 320-detector row unit. Estimated radiation exposure and image quality were compared with those from 100 consecutive patients who underwent imaging with a previous first-generation scanner. Effective radiation dose was estimated by multiplying the dose-length product by an effective dose conversion factor of 0.014 mSv/mGy ⋅ cm and reported with size-specific dose estimates (SSDEs). Image quality was evaluated by two independent readers. RESULTS The mean age of the 107 patients was 55.4 years ± 12.0 (standard deviation); 57 patients (53.3%) were men. The median body mass index was 27.3 kg/m(2) (range, 18.1-47.2 kg/m(2)); however, 71 patients (66.4%) were overweight, obese, or morbidly obese. A tube potential of 100 kV was used in 97 patients (90.6%), single-volume acquisition was used in 104 (97.2%), and prospective electrocardiographic gating was used in 106 (99.1%). The mean heart rate was 57.1 beats per minute ± 11.2 (range, 34-96 beats per minute), which enabled single-heartbeat scans in 100 patients (93.4%). The median radiation dose was 0.93 mSv (interquartile range [IQR], 0.58-1.74 mSv) with the second-generation unit and 2.67 mSv (IQR, 1.68-4.00 mSv) with the first-generation unit (P < .0001). The median SSDE was 6.0 mGy (IQR, 4.1-10.0 mGy) with the second-generation unit and 13.2 mGy (IQR, 10.2-18.6 mGy) with the first-generation unit (P < .0001). Overall, the radiation dose was less than 0.5 mSv for 23 of the 107 CT angiography examinations (21.5%), less than 1 mSv for 58 (54.2%), and less than 4 mSv for 103 (96.3%). All studies were of diagnostic quality, with most having excellent image quality. Three of four image quality indexes were significantly better with the second-generation unit compared with the first-generation unit. CONCLUSION The combination of a gantry rotation time of 275 msec, wide volume coverage, iterative reconstruction, automated exposure control, and larger x-ray power generator of the second-generation CT scanner provides excellent image quality over a wide range of body sizes and heart rates at low radiation doses. SUPPLEMENTAL MATERIAL http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.13122621/-/DC1.
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Affiliation(s)
- Marcus Y Chen
- Advanced Cardiovascular Imaging Laboratory, Cardiovascular and Pulmonary Branch, National Heart Lung and Blood Institute, National Institutes of Health, Department of Health and Human Services, 10 Center Dr, Building 10, Room B1D416, Bethesda, MD 20892-1061, USA.
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