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Dehlinger N, Bach J, Willaume T, Ohana M, Dillenseger JP. Accuracy of iodine quantification in dual energy CT: A phantom study across 3 different CT systems. Radiography (Lond) 2024; 30:226-230. [PMID: 38035437 DOI: 10.1016/j.radi.2023.11.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Revised: 10/30/2023] [Accepted: 11/14/2023] [Indexed: 12/02/2023]
Abstract
INTRODUCTION No study has rigorously compared the performances of iodine quantification on recent CT systems employing different emission-based technologies, depending on the manufacturers and models. METHODS A specific bespoke phantom was used for this study, with 12 known concentrations of iodinated contrast agent: 0.4, 0.5, 1.0, 2.0, 3.0, 4.0, 5.0, 10.0, 15.0, 20.0, 30.0 and 50.0 mg/mL. Three different dual-energy scanners were tested: one system using dual-source acquisition (CT#1) and two systems using Fast kilovolt-peak switching technology ± artificial intelligence (AI) reconstruction methods (CT#2 and #3) from two different manufacturers. For each system, helical scans were performed following recommended clinical protocols. Four acquisitions were performed per iodine concentration (mg/mL), and measurements were made on iodine-maps using ROIs. Mean measured values were compared to the known concentrations, and the absolute quantification error (AQE) and the relative percentage error (RPE) were used to compare the performances of each CT. RESULTS The accuracy of the obtained measurements varied depending on the studied model but not on the acquisition mode (dual-source vs kVp switch ± AI). The quantification was more precise at high concentrations. RPE values were below 10 % with CT#2 (kVp switch) and below 25 % with CT#1 (dual-source), but were significantly higher with CT#3 (kVp switch + AI), exceeding 50 % at low concentrations (<3 mg/mL). CONCLUSIONS With the help of a phantom, we identified variability in the results accuracy depending on the CT model, with sometimes significant deviation. Considering the performances of the different DECT technologies in iodine mapping, dual-source (CT#1) and kVp switch (CT#2) technologies appear more accurate than kVp switch technology combined with deep-learning-based reconstruction (CT#3) especially at low concentrations (<3 mg/mL). IMPLICATIONS FOR PRACTICE As the primary and daily user of medical imaging devices, the radiographer role is to be attentive to the performance of imaging systems, particularly when performing quantitative acquisitions like iodine-quantification. In CT quantitative imaging (iodine map), it's essential for radiographers to consider their CT systems as measuring tools, and to be aware of their accuracies and limits.
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Affiliation(s)
- N Dehlinger
- Pole d'imagerie médicale, Hôpitaux universitaire de Strasbourg, Strasbourg, France
| | - J Bach
- Pole d'imagerie médicale, Hôpitaux universitaire de Strasbourg, Strasbourg, France
| | - T Willaume
- Pole d'imagerie médicale, Hôpitaux universitaire de Strasbourg, Strasbourg, France
| | - M Ohana
- Pole d'imagerie médicale, Hôpitaux universitaire de Strasbourg, Strasbourg, France; ICube - UMR 7357, CNRS, Université de Strasbourg, Strasbourg, France; Faculté de médecine, maïeutique et des sciences de la santé, Université de Strasbourg, Strasbourg, France
| | - J P Dillenseger
- Pole d'imagerie médicale, Hôpitaux universitaire de Strasbourg, Strasbourg, France; ICube - UMR 7357, CNRS, Université de Strasbourg, Strasbourg, France; Faculté de médecine, maïeutique et des sciences de la santé, Université de Strasbourg, Strasbourg, France.
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Farag A, Fielding J, Catanzano T. Role of Dual-energy Computed Tomography in Diagnosis of Acute Pulmonary Emboli, a Review. Semin Ultrasound CT MR 2022; 43:333-343. [PMID: 35738818 DOI: 10.1053/j.sult.2022.04.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Prompt diagnosis of pulmonary embolism is essential to avert morbidity and mortality. There are a number of diagnostic options for identification of a pulmonary embolism, including laboratory and imaging investigations. While computed tomography pulmonary angiography (CTPA) has largely supplanted nuclear medicine ventilation/perfusion studies, there remain significant limitations in the optimal performance of CTPA. Dual-energy computed tomography has the ability to overcome many of the limitations of standard of care CTPA, including rescue of poor contrast boluses and the ability to evaluate pulmonary perfusion defects.
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Affiliation(s)
- Ahmed Farag
- Department of Radiology, UMass Chan Medical School-Baystate, Springfield, MA
| | - Jordan Fielding
- Department of Radiology, UMass Chan Medical School-Baystate, Springfield, MA
| | - Tara Catanzano
- Department of Radiology, UMass Chan Medical School-Baystate, Springfield, MA.
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Do TD, Skornitzke S, Merle U, Kittel M, Hofbaur S, Melzig C, Kauczor HU, Wielpütz MO, Weinheimer O. COVID-19 pneumonia: Prediction of patient outcome by CT-based quantitative lung parenchyma analysis combined with laboratory parameters. PLoS One 2022; 17:e0271787. [PMID: 35905122 PMCID: PMC9337660 DOI: 10.1371/journal.pone.0271787] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Accepted: 07/07/2022] [Indexed: 12/23/2022] Open
Abstract
Objectives To evaluate the prognostic value of fully automatic lung quantification based on spectral computed tomography (CT) and laboratory parameters for combined outcome prediction in COVID-19 pneumonia. Methods CT images of 53 hospitalized COVID-19 patients including virtual monochromatic reconstructions at 40-140keV were analyzed using a fully automated software system. Quantitative CT (QCT) parameters including mean and percentiles of lung density, fibrosis index (FIBI-700, defined as the percentage of segmented lung voxels ≥-700 HU), quantification of ground-glass opacities and well-aerated lung areas were analyzed. QCT parameters were correlated to laboratory and patient outcome parameters (hospitalization, days on intensive care unit, invasive and non-invasive ventilation). Results Best correlations were found for laboratory parameters LDH (r = 0.54), CRP (r = 0.49), Procalcitonin (r = 0.37) and partial pressure of oxygen (r = 0.35) with the QCT parameter 75th percentile of lung density. LDH, Procalcitonin, 75th percentile of lung density and FIBI-700 were the strongest independent predictors of patients’ outcome in terms of days of invasive ventilation. The combination of LDH and Procalcitonin with either 75th percentile of lung density or FIBI-700 achieved a r2 of 0.84 and 1.0 as well as an area under the receiver operating characteristic curve (AUC) of 0.99 and 1.0 for the prediction of the need of invasive ventilation. Conclusions QCT parameters in combination with laboratory parameters could deliver a feasible prognostic tool for the prediction of invasive ventilation in patients with COVID-19 pneumonia.
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Affiliation(s)
- Thuy D. Do
- Clinic for Diagnostic and Interventional Radiology (DIR), University Hospital Heidelberg, Heidelberg, Germany
- Translational Lung Research Center Heidelberg (TLRC), German Center for Lung Research (DZL), Heidelberg, Germany
| | - Stephan Skornitzke
- Clinic for Diagnostic and Interventional Radiology (DIR), University Hospital Heidelberg, Heidelberg, Germany
| | - Uta Merle
- Department of Internal Medicine IV (Gastroenterology and Infectious Disease), University Hospital Heidelberg, Heidelberg, Germany
| | - Maximilian Kittel
- Institute for Clinical Chemistry, Medical Faculty Mannheim of Heidelberg University, Mannheim, Germany
| | - Stefan Hofbaur
- Clinic for Gastroenterology and Nephrology, Landshut Hospital, Landshut, Germany
| | - Claudius Melzig
- Clinic for Diagnostic and Interventional Radiology (DIR), University Hospital Heidelberg, Heidelberg, Germany
- Translational Lung Research Center Heidelberg (TLRC), German Center for Lung Research (DZL), Heidelberg, Germany
| | - Hans-Ulrich Kauczor
- Clinic for Diagnostic and Interventional Radiology (DIR), University Hospital Heidelberg, Heidelberg, Germany
- Translational Lung Research Center Heidelberg (TLRC), German Center for Lung Research (DZL), Heidelberg, Germany
- Department of Diagnostic and Interventional Radiology with Nuclear Medicine, Thoraxklinik, University Hospital Heidelberg, Heidelberg, Germany
| | - Mark O. Wielpütz
- Clinic for Diagnostic and Interventional Radiology (DIR), University Hospital Heidelberg, Heidelberg, Germany
- Translational Lung Research Center Heidelberg (TLRC), German Center for Lung Research (DZL), Heidelberg, Germany
- Department of Diagnostic and Interventional Radiology with Nuclear Medicine, Thoraxklinik, University Hospital Heidelberg, Heidelberg, Germany
| | - Oliver Weinheimer
- Clinic for Diagnostic and Interventional Radiology (DIR), University Hospital Heidelberg, Heidelberg, Germany
- Translational Lung Research Center Heidelberg (TLRC), German Center for Lung Research (DZL), Heidelberg, Germany
- * E-mail:
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Differentiation Between Solitary Pulmonary Inflammatory Lesions and Solitary Cancer Using Gemstone Spectral Imaging. J Comput Assist Tomogr 2022; 46:300-307. [PMID: 35081600 DOI: 10.1097/rct.0000000000001268] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
BACKGROUND The distinction between solitary inflammatory lesion and solitary lung cancer remains a challenge because of their considerable overlapping computed tomography (CT) imaging features. PURPOSE This study aimed to verify whether spectral CT parameters can differentiate solitary lung cancer from solitary inflammatory lesions and to find their correlations with lesion size. METHODS A total of 78 patients with solitary lung lesions were included in our study. All of them underwent enhanced CT scans with Gemstone Spectral Imaging (GSI) mode, which was one of the dual-energy imaging technologies. According to maximum diameter (Dmax) of the lesion, regions of interest were collected and divided into inflammatory (group I: <3 cm [IA], n = 17; ≥3 cm [IB], n = 14) and cancer groups (group II: <3 cm [IIA], n = 20; ≥3 cm [IIB], n = 27). Computed tomography values (HU40keV, HU70keV), effective atomic number (Zeff), iodine concentration (IC), normalized IC (NIC), and spectral curve slopes (λ30, λ40) of each region of interest were calculated. The NIC was defined as the IC ratio of the lesion to the descending aorta. Mann-Whitney U test was used for intergroup (I vs II, IA vs IIA, IB vs IIB) and intragroup (IA vs IB, IIA vs IIB) comparisons, and receiver operating characteristic curve analysis was performed. Correlation analysis was applied to find the relationship between Dmax and GSI parameters. RESULTS No significant correlation was found between GSI parameters and Dmax in the inflammatory group, whereas inverse correlations were found in the cancer group. Gemstone spectral imaging parameters (except HU70keV) of group IIA were significantly higher than those of group IIB. There were significant differences in HU40keV, IC, NIC, λ30, and λ40 between groups IB and IIB under both arterial and venous phase (P values < 0.05), whereas the area under the curve for λ30 under venous phase was largest, and sensitivity and specificity were 96.32% and 85.71%, respectively. However, only HU40keV and HU70keV values under the arterial phase of IIA were significantly higher than those of IA. CONCLUSIONS Quantitative parameters of GSI demonstrated an inverse correlation with the lesion size of solitary lung cancer, and GSI parameters can be new ways to differentiate solitary lung cancer from solitary inflammatory lesions.
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Yang L, Sun J, Li J, Peng Y. Dual-energy spectral CT imaging of pulmonary embolism with Mycoplasma pneumoniae pneumonia in children. Radiol Med 2022; 127:154-161. [PMID: 35034318 DOI: 10.1007/s11547-021-01442-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2021] [Accepted: 12/21/2021] [Indexed: 11/24/2022]
Abstract
BACKGROUND Pulmonary embolism (PE) associated with Mycoplasma pneumoniae pneumonia (MPP) in children has already attracted more attention. CT pulmonary angiography (CTPA) has been the preferred method for diagnosing PE, but it has some limitations, especially for children. Dual-energy spectral CT has been used in diagnosing PE in adults. PURPOSE To evaluate the application of dual-energy spectral CT in diagnosing PE in children with MPP. MATERIALS AND METHODS Eighty-three children with MPP and highly suspected PE, underwent CTPA with spectral imaging mode, 25 children were diagnosis with PE. Noise, clot-to-artery contrast-to-noise ratio, image quality and diagnosis confidence were calculated and assessed on nine monochromatic image sets (40 to 80 keV). CTPA images were observed for the presence, localization and embolic degrees of PE. Clots were divided into intra- and extra-consolidation clots. For extra-consolidation clots, iodine concentration (IC) of perfusion defects and normal lung, perfusion defects of four children before and after the treatment were measured and compared. For intra-consolidation clots, IC of consolidation areas with clots and consolidation areas without clot were measured and compared. RESULTS The optimal energy level for detecting PE in children was 55 keV. 116 clots (29 extra-consolidations) were found, IC of defect regions was 0.69 ± 0.28 mg/mL (extra-consolidations) and 0.90 ± 0.23 mg/mL (intra-consolidations), both significantly lower than the 2.76 ± 0.45 mg/mL in normal lungs and 10.25 ± 1.76 mg/mL in consolidations without clots (P < 0.001). Significant difference was found in the presence or absence of perfusion defects between occlusive clots and nonocclusive clots (P < 0.001). IC of the perfusion defects significantly increased after treatment (P < 0.001). CONCLUSIONS In dual-energy spectral CTPA, 55 keV images optimize PE detection for children, and MD images quantify pulmonary blood flow of PE, and may help to detect small clots and quantify embolic degrees.
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Affiliation(s)
- Lixin Yang
- Department of Radiology, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, No.56, Nanlishi Road, Xicheng District, 100045, Beijing, China
| | - Jihang Sun
- Department of Radiology, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, No.56, Nanlishi Road, Xicheng District, 100045, Beijing, China
| | | | - Yun Peng
- Department of Radiology, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, No.56, Nanlishi Road, Xicheng District, 100045, Beijing, China.
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Hong YJ, Shim J, Lee SM, Im DJ, Hur J. Dual-Energy CT for Pulmonary Embolism: Current and Evolving Clinical Applications. Korean J Radiol 2021; 22:1555-1568. [PMID: 34448383 PMCID: PMC8390816 DOI: 10.3348/kjr.2020.1512] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Revised: 02/22/2021] [Accepted: 03/19/2021] [Indexed: 12/12/2022] Open
Abstract
Pulmonary embolism (PE) is a potentially fatal disease if the diagnosis or treatment is delayed. Currently, multidetector computed tomography (MDCT) is considered the standard imaging method for diagnosing PE. Dual-energy CT (DECT) has the advantages of MDCT and can provide functional information for patients with PE. The aim of this review is to present the potential clinical applications of DECT in PE, focusing on the diagnosis and risk stratification of PE.
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Affiliation(s)
- Yoo Jin Hong
- Department of Radiology and Research Institute of Radiological Science, Severance Hospital, Yonsei University College of Medicine, Seoul, Korea
| | - Jina Shim
- Department of Radiology and Research Institute of Radiological Science, Severance Hospital, Yonsei University College of Medicine, Seoul, Korea
| | - Sang Min Lee
- Department of Radiology and Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
| | - Dong Jin Im
- Department of Radiology and Research Institute of Radiological Science, Severance Hospital, Yonsei University College of Medicine, Seoul, Korea
| | - Jin Hur
- Department of Radiology and Research Institute of Radiological Science, Severance Hospital, Yonsei University College of Medicine, Seoul, Korea.
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Ropp AM, Burke AP, Kligerman SJ, Leb JS, Frazier AA. Intimal Sarcoma of the Great Vessels. Radiographics 2021; 41:361-379. [PMID: 33646906 DOI: 10.1148/rg.2021200184] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Intimal sarcomas of the pulmonary artery and aorta are rare entities with a poor prognosis. In many instances, pulmonary artery sarcomas are misinterpreted as acute or chronic pulmonary thromboembolism, whereas aortic intimal sarcomas are often misdiagnosed as protuberant atherosclerotic disease or intimal thrombus. Discernment of intimal sarcomas from these and other common benign entities is essential for the timely initiation of aggressive therapy. The most useful imaging modalities for assessment of a suspected intimal sarcoma include CT angiography, fluorine 18-fluorodeoxyglucose PET, and MRI. The authors discuss the clinical features, current treatment options, characteristic imaging findings, and underlying pathologic features of intimal sarcomas. The authors emphasize imaging discernment of intimal sarcomas and how their differential diagnosis is informed by knowledge of radiologic-pathologic correlation. The most reliable distinguishing imaging features are also emphasized to improve accurate and timely diagnosis. Online supplemental material is available for this article. ©RSNA, 2021.
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Affiliation(s)
- Alan M Ropp
- Department of Radiology and Medical Imaging, University of Virginia School of Medicine, 1215 Lee St, Charlottesville, VA 22903 (A.M.R.); Departments of Pathology (A.P.B.) and Diagnostic Radiology and Nuclear Medicine (A.A.F.), University of Maryland School of Medicine, Baltimore, Md; Department of Diagnostic Radiology, University of California San Diego School of Medicine, San Diego, Calif (S.J.K.); Department of Diagnostic Radiology, Columbia University Medical Center, New York, NY (J.S.L.); and American Institute for Radiologic Pathology Program (AIRP), American College of Radiology, Silver Spring, Md, and Department of Radiology and Radiological Sciences, Uniformed Services University of the Health Sciences (USUHS), Bethesda, Md (A.A.F.)
| | - Allen P Burke
- Department of Radiology and Medical Imaging, University of Virginia School of Medicine, 1215 Lee St, Charlottesville, VA 22903 (A.M.R.); Departments of Pathology (A.P.B.) and Diagnostic Radiology and Nuclear Medicine (A.A.F.), University of Maryland School of Medicine, Baltimore, Md; Department of Diagnostic Radiology, University of California San Diego School of Medicine, San Diego, Calif (S.J.K.); Department of Diagnostic Radiology, Columbia University Medical Center, New York, NY (J.S.L.); and American Institute for Radiologic Pathology Program (AIRP), American College of Radiology, Silver Spring, Md, and Department of Radiology and Radiological Sciences, Uniformed Services University of the Health Sciences (USUHS), Bethesda, Md (A.A.F.)
| | - Seth J Kligerman
- Department of Radiology and Medical Imaging, University of Virginia School of Medicine, 1215 Lee St, Charlottesville, VA 22903 (A.M.R.); Departments of Pathology (A.P.B.) and Diagnostic Radiology and Nuclear Medicine (A.A.F.), University of Maryland School of Medicine, Baltimore, Md; Department of Diagnostic Radiology, University of California San Diego School of Medicine, San Diego, Calif (S.J.K.); Department of Diagnostic Radiology, Columbia University Medical Center, New York, NY (J.S.L.); and American Institute for Radiologic Pathology Program (AIRP), American College of Radiology, Silver Spring, Md, and Department of Radiology and Radiological Sciences, Uniformed Services University of the Health Sciences (USUHS), Bethesda, Md (A.A.F.)
| | - Jay S Leb
- Department of Radiology and Medical Imaging, University of Virginia School of Medicine, 1215 Lee St, Charlottesville, VA 22903 (A.M.R.); Departments of Pathology (A.P.B.) and Diagnostic Radiology and Nuclear Medicine (A.A.F.), University of Maryland School of Medicine, Baltimore, Md; Department of Diagnostic Radiology, University of California San Diego School of Medicine, San Diego, Calif (S.J.K.); Department of Diagnostic Radiology, Columbia University Medical Center, New York, NY (J.S.L.); and American Institute for Radiologic Pathology Program (AIRP), American College of Radiology, Silver Spring, Md, and Department of Radiology and Radiological Sciences, Uniformed Services University of the Health Sciences (USUHS), Bethesda, Md (A.A.F.)
| | - Aletta A Frazier
- Department of Radiology and Medical Imaging, University of Virginia School of Medicine, 1215 Lee St, Charlottesville, VA 22903 (A.M.R.); Departments of Pathology (A.P.B.) and Diagnostic Radiology and Nuclear Medicine (A.A.F.), University of Maryland School of Medicine, Baltimore, Md; Department of Diagnostic Radiology, University of California San Diego School of Medicine, San Diego, Calif (S.J.K.); Department of Diagnostic Radiology, Columbia University Medical Center, New York, NY (J.S.L.); and American Institute for Radiologic Pathology Program (AIRP), American College of Radiology, Silver Spring, Md, and Department of Radiology and Radiological Sciences, Uniformed Services University of the Health Sciences (USUHS), Bethesda, Md (A.A.F.)
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Afat S, Othman AE, Nikolaou K, Gassenmaier S. Dual-Energy Computed Tomography of the Lung in COVID-19 Patients: Mismatch of Perfusion Defects and Pulmonary Opacities. Diagnostics (Basel) 2020; 10:E870. [PMID: 33114478 PMCID: PMC7693945 DOI: 10.3390/diagnostics10110870] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2020] [Revised: 10/14/2020] [Accepted: 10/23/2020] [Indexed: 01/08/2023] Open
Abstract
To evaluate contrast-enhanced dual-energy computed tomography (DECT) chest examinations regarding pulmonary perfusion patterns and pulmonary opacities in patients with confirmed COVID-19 disease. Fourteen patients with 24 DECT examinations performed between April and May 2020 were included in this retrospective study. DECT studies were assessed independently by two radiologists regarding pulmonary perfusion defects, using a Likert scale ranging from 1 to 4. Furthermore, in all imaging studies the extent of pulmonary opacities was quantified using the same rating system as for perfusion defects. The main pulmonary findings were ground glass opacities (GGO) in all 24 examinations and pulmonary consolidations in 22 examinations. The total lung scores after the addition of the scores of the single lobes showed significantly higher values of opacities compared to perfusion defects, with a median of 12 (9-18) for perfusion defects and a median of 17 (15-19) for pulmonary opacities (p = 0.002). Furthermore, mosaic perfusion patterns were found in 19 examinations in areas with and without GGO. Further studies will be necessary to investigate the pathophysiological background of GGO with maintained perfusion compared to GGO with reduced perfusion, especially regarding long-term lung damage and prognosis.
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Affiliation(s)
| | - Ahmed E. Othman
- Department of Diagnostic and Interventional Radiology, Eberhard-Karls-University Tuebingen, 72076 Tuebingen, Germany; (S.A.); (K.N.); (S.G.)
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Spectral CT in Lung Cancer: Usefulness of Iodine Concentration for Evaluation of Tumor Angiogenesis and Prognosis. AJR Am J Roentgenol 2020; 215:595-602. [PMID: 32569515 DOI: 10.2214/ajr.19.22688] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
OBJECTIVE. The purpose of this study was to investigate the correlation between iodine concentration (IC) derived from spectral CT and angiogenesis and the relationships between IC and clinical-pathologic features associated with lung cancer prognosis. SUBJECTS AND METHODS. Sixty patients with lung cancer were enrolled and underwent spectral CT. The IC, IC difference (ICD), and normalized IC (NIC) of tumors were measured in the arterial phase, venous phase (VP), and delayed phase. The microvessel densities (MVDs) of CD34-stained specimens were evaluated. Correlation analysis was performed for IC and MVD. The relationships between the IC index showing the best correlations with MVD and clinical-pathologic findings of pathologic types, histologic differentiation, tumor size, lymph node status, pathologic TNM stage, and intratumoral necrosis were investigated. RESULTS. The mean (± IQR) MVD of all tumors was 42.00 ± 27.50 vessels per field at ×400 magnification, with two MVD distribution types. The MVD of lung cancer correlated positively with the IC, ICD, and NIC on three-phase contrast-enhanced scanning (r range, 0.581-0.800; all p < 0.001), and the IC in the VP showed the strongest correlation with MVD (r = 0.800; p < 0.001). The correlations between IC and MVD, ICD and MVD, and NIC and MVD varied depending on whether the same scanning phase or same IC index was used. The IC in the VP showed statistically significant differences in the pathologic types of adenocarcinoma and squamous cell carcinoma, histologic differentiation, tumor size, and status of intratumoral necrosis of lung cancer (p < 0.05), but was not associated with nodal metastasis and pathologic TNM stages (p > 0.05). CONCLUSION. IC indexes derived from spectral CT, especially the IC in the VP, were useful indicators for evaluating tumor angiogenesis and prognosis.
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Wei TMD, Ning WMD, Yao HMD, Yujie WMD, Lin NMD. Correlation between Clinicopathological Features and Spectral CT Imaging of Lung Squamous Cell Carcinoma. ADVANCED ULTRASOUND IN DIAGNOSIS AND THERAPY 2020. [DOI: 10.37015/audt.2020.190027] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
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Dual-Energy Computed Tomography in Thoracic Imaging—Current Practices and Utility. J Thorac Imaging 2019; 35:W43-W50. [DOI: 10.1097/rti.0000000000000450] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Rajiah P, Tanabe Y, Partovi S, Moore A. State of the art: utility of multi-energy CT in the evaluation of pulmonary vasculature. Int J Cardiovasc Imaging 2019; 35:1509-1524. [PMID: 31049753 DOI: 10.1007/s10554-019-01615-8] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Accepted: 04/25/2019] [Indexed: 12/14/2022]
Abstract
Multi-energy computed tomography (MECT) refers to acquisition of CT data at multiple energy levels (typically two levels) using different technologies such as dual-source, dual-layer and rapid tube voltage switching. In addition to conventional/routine diagnostic images, MECT provides additional image sets including iodine maps, virtual non-contrast images, and virtual monoenergetic images. These image sets provide tissue/material characterization beyond what is possible with conventional CT. MECT provides invaluable additional information in the evaluation of pulmonary vasculature, primarily by the assessment of pulmonary perfusion. This functional information provided by the MECT is complementary to the morphological information from a conventional CT angiography. In this article, we review the technique and applications of MECT in the evaluation of pulmonary vasculature.
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Affiliation(s)
- Prabhakar Rajiah
- Cardiothoracic Imaging Division, Department of Radiology, University of Texas Southwestern Medical Center, E6.122G, 5323 Harry Hines Boulevard, Mail Code 9316, Dallas, TX, 75390-8896, USA.
| | - Yuki Tanabe
- Cardiothoracic Imaging Division, Department of Radiology, University of Texas Southwestern Medical Center, E6.122G, 5323 Harry Hines Boulevard, Mail Code 9316, Dallas, TX, 75390-8896, USA
- Ehime University Graduate School of Medicine, Ehime, Japan
| | - Sasan Partovi
- Interventional Radiology Section, Imaging Institute, Cleveland Clinic Foundation, Cleveland, OH, USA
| | - Alastair Moore
- Department of Radiology, Baylor University Medical Center, Dallas, TX, USA
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Große Hokamp N, Gupta A. Evaluation of lung transplant perfusion using iodine maps from novel spectral detector computed tomography. Indian J Radiol Imaging 2018; 28:436-438. [PMID: 30662205 PMCID: PMC6319111 DOI: 10.4103/ijri.ijri_35_18] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
We report the case of a 51-year-old patient who underwent bilateral lung transplantation and presented with an unstable condition and sepsis 6 days after transplantation. The performed contrast enhanced spectral detector computed tomography (CT) using a dual-layer detector showed absence of perfusion in the left lung on iodine maps, although branches of the pulmonary artery were patent. This prompted retrospective evaluation of CT images and total venous occlusion of the left pulmonary veins was found. Here, iodine maps helped in raising conspicuity of loss of lung perfusion.
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Affiliation(s)
- Nils Große Hokamp
- Department of Radiology, University Hospitals Cleveland Medical Center, Case Western Reserve University, Cleveland, OH, USA
- Department of Radiology, Case School of Medicine, Case Western Reserve University, Cleveland, OH, USA
| | - Amit Gupta
- Department of Radiology, University Hospitals Cleveland Medical Center, Case Western Reserve University, Cleveland, OH, USA
- Department of Radiology, Case School of Medicine, Case Western Reserve University, Cleveland, OH, USA
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Ma G, YU Y, Duan H, Dou Y, Jia Y, Zhang X, Yang C, Chen X, Han D, Guo C, He T. Subtraction CT angiography in head and neck with low radiation and contrast dose dual-energy spectral CT using rapid kV-switching technique. Br J Radiol 2018; 91:20170631. [PMID: 29412008 PMCID: PMC6223275 DOI: 10.1259/bjr.20170631] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2017] [Revised: 01/15/2018] [Accepted: 02/01/2018] [Indexed: 11/05/2022] Open
Abstract
OBJECTIVE To investigate the application of low radiation and contrast dose spectral CT angiology using rapid kV-switching technique in the head and neck with subtraction method for bone removal. METHODS This prospective study was approved by the local ethics committee. 64 cases for head and neck CT angiology were randomly divided into Groups A (n = 32) and B (n = 32). Group A underwent unenhanced CT with 100 kVp, 200 mA and contrast-enhanced CT with spectral CT mode with body mass index-dependent low dose protocols. Group B used conventional helical scanning with 120 kVp, auto mA for noise index of 12 HU (Hounsfield unit) for both the unenhanced and contrast-enhanced CT. Subtraction images were formed by subtracting the unenhanced images from enhanced images (with the 65 keV-enhanced spectral CT image in Group A). CT numbers and their standard deviations in aortic arch, carotid arteries, middle cerebral artery and air were measured in the subtraction images. The signal-to-noise ratio and contrast-to-noise ratio for the common and internal carotid arteries and middle cerebral artery were calculated. Image quality in terms of bone removal effect was evaluated by two experienced radiologists independently and blindly using a 4-point system. Radiation dose and total iodine load were recorded. Measurements were statistically compared between the two groups. RESULTS The two groups had same demographic results. There was no difference in the CT number, signal-to-noise and contrast-to-noise ratio values for carotid arteries and middle cerebral artery in the subtraction images between the two groups (p > 0.05). However, the bone removal effect score [median (min-max)] in Group A [4 (3-4)] was rated better than in Group B [3 (2-4)] (p < 0.001), with excellent agreement between the two observers (κ > 0.80). The radiation dose in Group A (average of 2.64 mSv) was 57% lower than the 6.18 mSv in Group B (p < 0.001). The total iodine intake in Group A was 13.5g, 36% lower than the 21g in Group B. CONCLUSION Spectral CT imaging with rapid kV-switching in the subtraction angiography in head and neck provides better bone removal with significantly reduced radiation and contrast dose compared with conventional subtraction method. Advances in knowledge: This novel method provides better bone removal with significant radiation and contrast dose reduction compared with the conventional subtraction CT, and maybe used clinically to protect the thyroid gland and ocular lenses from unnecessary high radiation.
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Affiliation(s)
- Guangming Ma
- Department of Diagnostic Radiology, Affiliated Hospital of Shaanxi University of Chinese Medicine, Xianyang, China
| | - Yong YU
- Department of Diagnostic Radiology, Affiliated Hospital of Shaanxi University of Chinese Medicine, Xianyang, China
| | - Haifeng Duan
- Department of Diagnostic Radiology, Affiliated Hospital of Shaanxi University of Chinese Medicine, Xianyang, China
| | - Yuequn Dou
- Department of Diagnostic Radiology, Affiliated Hospital of Shaanxi University of Chinese Medicine, Xianyang, China
| | - Yongjun Jia
- Department of Diagnostic Radiology, Affiliated Hospital of Shaanxi University of Chinese Medicine, Xianyang, China
| | - Xirong Zhang
- Department of Diagnostic Radiology, Affiliated Hospital of Shaanxi University of Chinese Medicine, Xianyang, China
| | - Chuangbo Yang
- Department of Diagnostic Radiology, Affiliated Hospital of Shaanxi University of Chinese Medicine, Xianyang, China
| | - Xiaoxia Chen
- Department of Diagnostic Radiology, Affiliated Hospital of Shaanxi University of Chinese Medicine, Xianyang, China
| | - Dong Han
- Department of Diagnostic Radiology, Affiliated Hospital of Shaanxi University of Chinese Medicine, Xianyang, China
| | - Changyi Guo
- Department of Diagnostic Radiology, The Second Affiliated Hospital of the Shannxi University of Traditional Chinese Medicine, Xianyang, China
| | - Taiping He
- Department of Diagnostic Radiology, Affiliated Hospital of Shaanxi University of Chinese Medicine, Xianyang, China
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Podgorsak AR, Venkataraman AC, Nagesh SVS, Bednarek DR, Rudin S, Siddiqui A, Ionita CN. Use of material decomposition in the context of neurovascular intervention using standard flat panel and a high-resolution CMOS detector. PROCEEDINGS OF SPIE--THE INTERNATIONAL SOCIETY FOR OPTICAL ENGINEERING 2018; 10578:105780L. [PMID: 29899592 PMCID: PMC5994751 DOI: 10.1117/12.2292564] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
The imaging of endovascular devices during neurovascular procedures such as the coiling of aneurysms guided with CBCT imaging may be challenging due to the presence of highly attenuating materials such as platinum in the coil and stent marker, nickel-titanium in the stent, iodine in the contrast agent, and tantalum in the embolization agent. The use of dual-energy imaging followed by a basis material decomposition image processing-scheme may improve the feature separation and recognition. Two sets of testing were performed to validate this concept. The first trial was the acquisition of dual-energy micro-CBCT data of a 3D-printed simple aneurysm model using a 49.5 μm pixel size CMOS detector (Teledyne DALSA, Waterloo, ON.). Two sets of projection data were acquired using beam energies of 35 kVp and 70 kVp. Axial slices were reconstructed and used to carry out the material decomposition processing. The second trial was the acquisition of dual-energy CBCT images of a RS-240T angiographic head phantom (Radiology Support Devices Inc., CA.) with an iodine vascular insert using a Toshiba Infinix BiPlane C-arm system coupled to a flat panel detector. Two sets of image data were acquired using beam energies of 80 kVp and 120 kVp. Following image reconstruction, slices of the phantom were decomposed using the same processing as previously. The resulting image data over both trials indicate that the decomposition process was successful in separating the kinds of materials commonly used during a neurovascular intervention, such as platinum, cobalt-chromium, and iodine. The normalized root mean square error metric was used to quantitatively assess this. This indicates a basis for future more clinically relevant testing of our methods.
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Affiliation(s)
- A R Podgorsak
- Department of Biomedical Engineering, University at Buffalo
- Toshiba (Canon) Stroke and Vascular Research Center, Buffalo, NY
| | - A C Venkataraman
- Toshiba (Canon) Stroke and Vascular Research Center, Buffalo, NY
| | | | - D R Bednarek
- Toshiba (Canon) Stroke and Vascular Research Center, Buffalo, NY
- Department of Radiology, University at Buffalo
| | - S Rudin
- Department of Biomedical Engineering, University at Buffalo
- Toshiba (Canon) Stroke and Vascular Research Center, Buffalo, NY
- Department of Radiology, University at Buffalo
- Department of Neurosurgery, University at Buffalo
| | - A Siddiqui
- Toshiba (Canon) Stroke and Vascular Research Center, Buffalo, NY
- Department of Neurosurgery, University at Buffalo
| | - C N Ionita
- Department of Biomedical Engineering, University at Buffalo
- Toshiba (Canon) Stroke and Vascular Research Center, Buffalo, NY
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Weis M, Henzler T, Nance JW, Haubenreisser H, Meyer M, Sudarski S, Schoenberg SO, Neff KW, Hagelstein C. Radiation Dose Comparison Between 70 kVp and 100 kVp With Spectral Beam Shaping for Non-Contrast-Enhanced Pediatric Chest Computed Tomography: A Prospective Randomized Controlled Study. Invest Radiol 2017; 52:155-162. [PMID: 27662576 DOI: 10.1097/rli.0000000000000325] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE The aim of this prospective randomized controlled study was to compare 2 techniques for radiation dose reduction in non-contrast-enhanced pediatric chest computed tomography (CT): low peak kilovoltage imaging at 70 kVp and spectral beam shaping at 100 kVp using a dedicated tin filter (100-kVp Sn). MATERIALS AND METHODS All chest CT examinations were performed on a third-generation dual-source CT system (SOMATOM Force; Siemens Healthineers, Germany). Fifty children (mean age, 6.8 ± 5.1 years) were examined using the 100-kVp Sn protocol, whereas 25 children received the 70-kVp protocol (mean age, 5.7 ± 5.2 years; 2:1 randomization scheme). Radiation metrics and organ doses were compared between acquisition techniques using commercially available radiation dose analysis software (Radimetrics Inc, Bayer AG, Toronto, Ontario, Canada). Objective image quality, expressed by signal-to-noise ratio and subjective image quality based on a 4-point scale (1, best; 4, worst image quality), were compared. RESULTS Volume CT dose index and size-specific dose estimate were significantly lower in the 100-kVp Sn group compared with the 70-kVp group (0.19 ± 0.12 mGy vs 0.81 ± 0.70 mGy and 0.34 ± 0.13 mGy vs 1.48 ± 1.11 mGy; P < 0.0001 for both). Accordingly, mean effective dose was significantly lower for the 100-kVp Sn examinations (0.21 ± 0.10 mSv) compared with the 70-kVp examinations (0.83 ± 0.49 mSv; P < 0.0001). Calculated organ doses were also significantly lower using the 100-kVp Sn protocol when compared with the 70-kVp protocol; for example, breast dose was reduced by a factor of 4.3. Signal-to-noise ratio was slightly superior for 70-kVp images while lung image quality of the 100-kVp Sn protocol was preferred in subjective analysis (P = 0.0004). CONCLUSIONS Pediatric chest CT performed at 100 kVp with an additional tin filter for spectral shaping significantly reduces radiation dose when compared with low peak kilovoltage imaging at 70 kVp and therefore should be preferred in non-contrast-enhanced pediatric chest CT examinations, particularly (given the improved subjective image quality) when the main focus is evaluation of the lung parenchyma.
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Affiliation(s)
- Meike Weis
- From the *Institute of Clinical Radiology and Nuclear Medicine, University Medical Center Mannheim, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany; and †Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC
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Iodine Concentration in Spectral CT: Assessment of Prognostic Determinants in Patients With Gastric Adenocarcinoma. AJR Am J Roentgenol 2017; 209:1033-1038. [PMID: 28871809 DOI: 10.2214/ajr.16.16895] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
OBJECTIVE The purpose of this study was to use virtual monochromatic spectral CT to investigate the usefulness of iodine concentration (IC) and its correlation with clinicopathologically determined prognostic factors in gastric adenocarcinoma. SUBJECTS AND METHODS From June 2012 to March 2015, 34 patients with gastric adenocarcinoma underwent arterial and portal venous phase spectral CT. The ICs in the arterial and portal venous phases were calculated and then normalized with the aorta as normalized IC (NIC). The surgical specimen was evaluated with CD34 staining to determine microvessel density (MVD). The correlation between imaging results and clinicopathologic findings was investigated for histologic grading, lymph node metastasis, serosal involvement, distant metastasis, pathologic TNM stage, and MVD. RESULTS The mean arterial phase NIC value of tumors was 0.12 ± 0.03, portal venous phase NIC value was 0.39 ± 0.06, and MVD was 26.94 ± 7.87 vessels per high-power field (×400). Both arterial phase and portal venous phase NIC values were significantly higher in poorly differentiated gastric adenocarcinomas (p = 0.005) than in moderately differentiated tumors (p = 0.013). There was no significant correlation between NIC and serosal involvement or distant metastasis. There was significant correlation between the NIC and MVD in gastric adenocarcinoma (arterial phase NIC, p = 0.013; portal venous phase NIC, p = 0.001). However, neither the arterial nor the portal venous phase NIC of gastric adenocarcinoma had a significant relation to lymphatic metastasis or pathologic TNM stage. There was a significant difference between the high and low MVD groups with respect to portal venous phase NIC (p = 0.045). CONCLUSION NIC can serve as a useful predictor of angiogenesis and degree of differentiation of moderately and poorly differentiated gastric adenocarcinomas.
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Characteristics of Chinese Costal Cartilage and Costa Calcification Using Dual-Energy Computed Tomography Imaging. Sci Rep 2017; 7:2923. [PMID: 28592818 PMCID: PMC5462740 DOI: 10.1038/s41598-017-02859-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2016] [Accepted: 04/20/2017] [Indexed: 11/08/2022] Open
Abstract
To assess characteristics of Chinese costal cartilage and costa calcification using Dual-Energy computed tomography(DECT). 154 patients who underwent chest DECT scanning were included in our study. They were divided into following groups: less than 30 years old, 31-40 years old, 41-50 years old, 51-60 years old and over 60 years old. The sixth, seventh and eighth costal cartilages and costas were evaluated. Calcification patterns of cartilage were classified as central(C), peripheral(P), mixed(M) and no calcification(N) types. Calcification degree of cartilage was distinguished as 1(0-25%), 2(26-50%) and 3(>50%). CT value, calcium and water concentrations were measured in costal cartilage, cortical or cancellous bone respectively. An increasing C pattern of cartilage was displayed in females, while P type preferred in males as age increased. Calcification degree generally changed from 1 to 2 or 3 in females. CT value and calcium concentration of cartilage went through a gradual rising course and peaked in their 40-50 years, while those two indices of cancellous bone decreased gradually since their 50 years in females. The findings suggest a gradual calcification of the costal cartilage took place before 40-50 years old and a sharp bone loss of the costa happened after 40-50 years old in females.
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Ohno Y, Koyama H, Lee HY, Miura S, Yoshikawa T, Sugimura K. Contrast-enhanced CT- and MRI-based perfusion assessment for pulmonary diseases: basics and clinical applications. Diagn Interv Radiol 2017; 22:407-21. [PMID: 27523813 DOI: 10.5152/dir.2016.16123] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Assessment of regional pulmonary perfusion as well as nodule and tumor perfusions in various pulmonary diseases are currently performed by means of nuclear medicine studies requiring radioactive macroaggregates, dual-energy computed tomography (CT), and dynamic first-pass contrast-enhanced perfusion CT techniques and unenhanced and dynamic first-pass contrast enhanced perfusion magnetic resonance imaging (MRI), as well as time-resolved three-dimensional or four-dimensional contrast-enhanced magnetic resonance angiography (MRA). Perfusion scintigraphy, single-photon emission tomography (SPECT) and SPECT fused with CT have been established as clinically available scintigraphic methods; however, they are limited by perfusion information with poor spatial resolution and other shortcomings. Although positron emission tomography with 15O water can measure absolute pulmonary perfusion, it requires a cyclotron for generation of a tracer with an extremely short half-life (2 min), and can only be performed for academic purposes. Therefore, clinicians are concentrating their efforts on the application of CT-based and MRI-based quantitative and qualitative perfusion assessment to various pulmonary diseases. This review article covers 1) the basics of dual-energy CT and dynamic first-pass contrast-enhanced perfusion CT techniques, 2) the basics of time-resolved contrast-enhanced MRA and dynamic first-pass contrast-enhanced perfusion MRI, and 3) clinical applications of contrast-enhanced CT- and MRI-based perfusion assessment for patients with pulmonary nodule, lung cancer, and pulmonary vascular diseases. We believe that these new techniques can be useful in routine clinical practice for not only thoracic oncology patients, but also patients with different pulmonary vascular diseases.
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Affiliation(s)
- Yoshiharu Ohno
- Division of Functional and Diagnostic Imaging Research, Department of Radiology and Advanced Biomedical Imaging Research Center, Kobe University Graduate School of Medicine, Kobe, Hyogo, Japan.
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Machida H, Tanaka I, Fukui R, Shen Y, Ishikawa T, Tate E, Ueno E. Dual-Energy Spectral CT: Various Clinical Vascular Applications. Radiographics 2017; 36:1215-32. [PMID: 27399244 DOI: 10.1148/rg.2016150185] [Citation(s) in RCA: 75] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Single-source dual-energy (DE) computed tomography (CT) with fast switching of tube voltage allows projection-based image reconstruction, substantial reduction of beam-hardening effects, reconstruction of accurate monochromatic images and material decomposition images (MDIs), and detailing of material composition by using x-ray spectral information. In vascular applications, DE CT is expected to overcome limitations of standard single-energy CT angiography, including patient exposure to nephrotoxic contrast medium and carcinogenic radiation, insufficient contrast vascular enhancement, interference from metallic and beam-hardening artifacts and severe vessel calcification, and limited tissue characterization and perfusion assessment. Acquisition of low-energy monochromatic images and iodine/water MDIs can reasonably reduce contrast agent dose and improve vessel enhancement. Acquisition of virtual noncontrast images, such as water/iodine MDIs, can reduce overall radiation exposure by replacing true noncontrast CT in each examination. Acquisition of monochromatic images by using metal artifact reduction software or acquisition of iodine/water MDIs can reduce metal artifacts with preserved or increased vessel contrast, and subtraction of monochromatic images between two energy levels can subtract coils composed of dense metallic materials. Acquisition of iodine/calcium (ie, hydroxyapatite) MDIs permits subtraction of vessel calcification and improves vessel lumen delineation. Sensitive detection of lipid-rich plaque can be achieved by using fat/water MDIs, the spectral Hounsfield unit curve (energy level vs CT attenuation), and a histogram of effective atomic numbers included in an image. Various MDIs are useful for accurate differentiation among materials with high attenuation values, including contrast medium, calcification, and fresh hematoma. Iodine/water MDIs are used to assess organ perfusion, such as in the lungs and myocardium. Understanding these DE CT techniques enhances the value of CT for vascular applications. (©)RSNA, 2016.
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Affiliation(s)
- Haruhiko Machida
- From the Department of Radiology, Tokyo Women's Medical University, Medical Center East, 2-1-10 Nishiogu, Arakawa-ku, Tokyo 116-8567, Japan
| | - Isao Tanaka
- From the Department of Radiology, Tokyo Women's Medical University, Medical Center East, 2-1-10 Nishiogu, Arakawa-ku, Tokyo 116-8567, Japan
| | - Rika Fukui
- From the Department of Radiology, Tokyo Women's Medical University, Medical Center East, 2-1-10 Nishiogu, Arakawa-ku, Tokyo 116-8567, Japan
| | - Yun Shen
- From the Department of Radiology, Tokyo Women's Medical University, Medical Center East, 2-1-10 Nishiogu, Arakawa-ku, Tokyo 116-8567, Japan
| | - Takuya Ishikawa
- From the Department of Radiology, Tokyo Women's Medical University, Medical Center East, 2-1-10 Nishiogu, Arakawa-ku, Tokyo 116-8567, Japan
| | - Etsuko Tate
- From the Department of Radiology, Tokyo Women's Medical University, Medical Center East, 2-1-10 Nishiogu, Arakawa-ku, Tokyo 116-8567, Japan
| | - Eiko Ueno
- From the Department of Radiology, Tokyo Women's Medical University, Medical Center East, 2-1-10 Nishiogu, Arakawa-ku, Tokyo 116-8567, Japan
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Podgorsak AR, Nagesh SS, Bednarek DR, Rudin S, Ionita CN. Implementation of material decomposition using an EMCCD and CMOS-based micro-CT system. PROCEEDINGS OF SPIE--THE INTERNATIONAL SOCIETY FOR OPTICAL ENGINEERING 2017. [PMID: 28649158 DOI: 10.1117/12.2253892] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
This project assessed the effectiveness of using two different detectors to obtain dual-energy (DE) micro-CT data for the carrying out of material decomposition. A micro-CT coupled to either a complementary metal-oxide semiconductor (CMOS) or an electron multiplying CCD (EMCCD) detector was used to acquire image data of a 3D-printed phantom with channels filled with different materials. At any instance, materials such as iohexol contrast agent, water, and platinum were selected to make up the scanned object. DE micro-CT data was acquired, and slices of the scanned object were differentiated by material makeup. The success of the decomposition was assessed quantitatively through the computation of percentage normalized root-mean-square error (%NRMSE). Our results indicate a successful decomposition of iohexol for both detectors (%NRMSE values of 1.8 for EMCCD, 2.4 for CMOS), as well as platinum (%NRMSE value of 4.7). The CMOS detector performed material decomposition on air and water on average with 7 times more %NRMSE, possibly due to the decreased sensitivity of the CMOS system. Material decomposition showed the potential to differentiate between materials such as the iohexol and platinum, perhaps opening the door for its use in the neurovascular anatomical region. Work supported by Toshiba America Medical Systems, and partially supported by NIH grant 2R01EB002873.
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Affiliation(s)
- Alexander R Podgorsak
- Department of Biomedical Engineering, University at Buffalo, NY.,Toshiba Stroke and Vascular Research Center, Buffalo, NY
| | | | | | - Stephen Rudin
- Department of Biomedical Engineering, University at Buffalo, NY.,Toshiba Stroke and Vascular Research Center, Buffalo, NY
| | - Ciprian N Ionita
- Department of Biomedical Engineering, University at Buffalo, NY.,Toshiba Stroke and Vascular Research Center, Buffalo, NY
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van Hamersvelt RW, Willemink MJ, de Jong PA, Milles J, Vlassenbroek A, Schilham AMR, Leiner T. Feasibility and accuracy of dual-layer spectral detector computed tomography for quantification of gadolinium: a phantom study. Eur Radiol 2017; 27:3677-3686. [PMID: 28124106 PMCID: PMC5544796 DOI: 10.1007/s00330-017-4737-8] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2016] [Revised: 12/12/2016] [Accepted: 01/03/2017] [Indexed: 01/24/2023]
Abstract
Objectives The aim of this study was to evaluate the feasibility and accuracy of dual-layer spectral detector CT (SDCT) for the quantification of clinically encountered gadolinium concentrations. Methods The cardiac chamber of an anthropomorphic thoracic phantom was equipped with 14 tubular inserts containing different gadolinium concentrations, ranging from 0 to 26.3 mg/mL (0.0, 0.1, 0.2, 0.4, 0.5, 1.0, 2.0, 3.0, 4.0, 5.1, 10.6, 15.7, 20.7 and 26.3 mg/mL). Images were acquired using a novel 64-detector row SDCT system at 120 and 140 kVp. Acquisitions were repeated five times to assess reproducibility. Regions of interest (ROIs) were drawn on three slices per insert. A spectral plot was extracted for every ROI and mean attenuation profiles were fitted to known attenuation profiles of water and pure gadolinium using in-house-developed software to calculate gadolinium concentrations. Results At both 120 and 140 kVp, excellent correlations between scan repetitions and true and measured gadolinium concentrations were found (R > 0.99, P < 0.001; ICCs > 0.99, CI 0.99–1.00). Relative mean measurement errors stayed below 10% down to 2.0 mg/mL true gadolinium concentration at 120 kVp and below 5% down to 1.0 mg/mL true gadolinium concentration at 140 kVp. Conclusion SDCT allows for accurate quantification of gadolinium at both 120 and 140 kVp. Lowest measurement errors were found for 140 kVp acquisitions. Key Points • Gadolinium quantification may be useful in patients with contraindication to iodine. • Dual-layer spectral detector CT allows for overall accurate quantification of gadolinium. • Interscan variability of gadolinium quantification using SDCT material decomposition is excellent.
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Affiliation(s)
- Robbert W van Hamersvelt
- Department of Radiology, University Medical Center Utrecht, P.O. Box 85500, 3508 GA, Utrecht, The Netherlands.
| | - Martin J Willemink
- Department of Radiology, University Medical Center Utrecht, P.O. Box 85500, 3508 GA, Utrecht, The Netherlands
| | - Pim A de Jong
- Department of Radiology, University Medical Center Utrecht, P.O. Box 85500, 3508 GA, Utrecht, The Netherlands
| | - Julien Milles
- CT Clinical Science, Philips HealthCare, Best, The Netherlands
| | | | - Arnold M R Schilham
- Department of Radiology, University Medical Center Utrecht, P.O. Box 85500, 3508 GA, Utrecht, The Netherlands
| | - Tim Leiner
- Department of Radiology, University Medical Center Utrecht, P.O. Box 85500, 3508 GA, Utrecht, The Netherlands
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Chen A, Liu A, Liu J, Tian S, Wang H, Liu Y. Application of dual-energy spectral CT imaging in differential diagnosis of bladder cancer and benign prostate hyperplasia. Medicine (Baltimore) 2016; 95:e5705. [PMID: 28033269 PMCID: PMC5207565 DOI: 10.1097/md.0000000000005705] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
The aim of this study was to explore the clinical value of dual-energy spectral CT imaging in the differential diagnosis between bladder cancer and benign prostate hyperplasia (BPH).We retrospectively analyzed images of 118 patients who received pelvic dual-energy spectral CT imaging. These patients were later confirmed to have bladder cancer in 61 patients and BPH in 57 patients. CT values of the 2 lesion types from 40 to 140 keV were measured from the monochromatic spectral CT image to generate spectral HU curves. The slope of the spectral curve and the lesion effective atomic number were calculated. The measured parameters were analyzed with independent-sample Mann-Whitney U test.There was a statistically significant difference in CT value between the 2 groups from 40 to 90 keV, with the biggest difference at 40 keV (median and interquartile range: 83.3 HU and 22.9 HU vs 60.6 HU and 16.7 HU, Z = 5.932, P < 0.001). The slope of the spectral HU curve for bladder cancer was markedly higher than that of BPH (median and interquartile range: 0.48 and 0.23 vs 0.26 and 0.22, Z = 5.162, P < 0.001); the difference in effective atomic number (median and interquartile range: 7.99 and 0.21 vs 7.80 and 0.20, Z = 5.233, P < 0.001) was also statistically significant.Dual-energy spectral CT imaging provides high sensitivity and specificity for differentiating bladder cancer from benign prostate hyperplasia.
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Hwang HJ, Hoffman EA, Lee CH, Goo JM, Levin DL, Kauczor HU, Seo JB. The role of dual-energy computed tomography in the assessment of pulmonary function. Eur J Radiol 2016; 86:320-334. [PMID: 27865580 DOI: 10.1016/j.ejrad.2016.11.010] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2016] [Revised: 11/02/2016] [Accepted: 11/04/2016] [Indexed: 01/05/2023]
Abstract
The assessment of pulmonary function, including ventilation and perfusion status, is important in addition to the evaluation of structural changes of the lung parenchyma in various pulmonary diseases. The dual-energy computed tomography (DECT) technique can provide the pulmonary functional information and high resolution anatomic information simultaneously. The application of DECT for the evaluation of pulmonary function has been investigated in various pulmonary diseases, such as pulmonary embolism, asthma and chronic obstructive lung disease and so on. In this review article, we will present principles and technical aspects of DECT, along with clinical applications for the assessment pulmonary function in various lung diseases.
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Affiliation(s)
- Hye Jeon Hwang
- Department of Radiology, Hallym University College of Medicine, Hallym University Sacred Heart Hospital, 22, Gwanpyeong-ro 170beon-gil, Dongan-gu, Anyang-si, Gyeonggi-do 431-796, Republic of Korea
| | - Eric A Hoffman
- Departments of Radiology, Medicine, and Biomedical Engineering, University of Iowa, 200 Hawkins Dr, CC 701 GH, Iowa City, IA 52241, United States
| | - Chang Hyun Lee
- Department of Radiology, Seoul National University College of Medicine, 103 Daehak-ro, Jongno-gu, Seoul 110-799, Republic of Korea
| | - Jin Mo Goo
- Department of Radiology, Seoul National University College of Medicine, 103 Daehak-ro, Jongno-gu, Seoul 110-799, Republic of Korea
| | - David L Levin
- Department of Radiology, Mayo Clinic College of Medicine, 200 First Street, SW, Rochester, MN 55905, United States
| | - Hans-Ulrich Kauczor
- Diagnostic and Interventional Radiology, University Hospital Heidelberg, Im Neuenheimer Feld 400, 69120 Heidelberg, Germany; Translational Lung Research Center Heidelberg (TLRC), Member of the German Center for Lung Research (DZL), Im Neuenheimer Feld 400, 69120 Heidelberg, Germany
| | - Joon Beom Seo
- Department of Radiology and Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, 388-1, Pungnap 2-dong, Songpa-ku, Seoul, 05505, Republic of Korea.
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Improving Image Quality for Lung Cancer Imaging With Optimal Monochromatic Energy Level in Dual Energy Spectral Computed Tomography. J Comput Assist Tomogr 2016; 40:243-7. [PMID: 26760189 DOI: 10.1097/rct.0000000000000357] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
OBJECTIVE The aim of this study was to find optimal monochromatic spectral computed tomography (CT) level to improve image quality of lung cancer. METHODS Fifty patients with lung cancers were scanned by spectral CT; monochromatic images at 50, 60, 70 and 80 keV energy levels were generated; and objective analysis including image noise, lesion-to-lung contrast-to-noise ratio, and CT number difference between central and peripheral regions of tumor (dCT value) were measured and compared. Subjective assessment about the overall image quality and inhomogeneity enhancement was compared. RESULTS The highest contrast-to-noise ratio value and subjective score of image quality were obtained at 70 keV, which were superior to those of 50- and 80-keV series (all P < 0.05). The subjective score of the inhomogeneity evaluation was peaked at 60-keV series and significantly higher than other energy levels (all P < 0.05). CONCLUSIONS Both objective and subjective image analysis of lung cancers may be improved with the combined observation of 60 keV and 70 keV monochromatic images in spectral CT.
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Lv P, Liu J, Yan X, Chai Y, Chen Y, Gao J, Pan Y, Li S, Guo H, Zhou Y. CT spectral imaging for monitoring the therapeutic efficacy of VEGF receptor kinase inhibitor AG-013736 in rabbit VX2 liver tumours. Eur Radiol 2016; 27:918-926. [PMID: 27287476 DOI: 10.1007/s00330-016-4458-4] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2016] [Revised: 04/21/2016] [Accepted: 05/30/2016] [Indexed: 11/25/2022]
Abstract
PURPOSE The aim of this study was to evaluate the value of computed tomography (CT) spectral imaging in assessing the therapeutic efficacy of a vascular endothelial growth factor (VEGF) receptor inhibitor AG-013736 in rabbit VX2 liver tumours. METHODS Twenty-three VX2 liver tumour-bearing rabbits were scanned with CT in spectral imaging mode during the arterial phase (AP) and portal phase (PP). The iodine concentrations(ICs)of tumours normalized to aorta (nICs) at different time points (baseline, 2, 4, 7, 10, and 14 days after treatment) were compared within the treated group (n = 17) as well as between the control (n = 6) and treated groups. Correlations between the tumour size, necrotic fraction (NF), microvessel density (MVD), and nICs were analysed. RESULTS The change of nICs relative to baseline in the treated group was lower compared to the control group. A greater decrease in the nIC of a tumour at 2 days was positively correlated with a smaller increase in tumour size at 14 days (P < 0.05 for both). The tumour nIC values in AP and PP had correlations with MVD (r = 0.71 and 0.52) and NF (r = -0.54 and -0.51) (P < 0.05 for all). CONCLUSIONS CT spectral imaging allows for the evaluation and early prediction of tumour response to AG-013736. KEY POINTS • AG-013736 treatment response was evaluated by CT in a rabbit tumour model. • CT spectral imaging allows for the early treatment monitoring of targeted anti-tumour therapies. • Spectral CT findings correlated with vascular changes after anti-tumour therapies. • Spectral CT is a promising method for assessing clinical treatment response.
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Affiliation(s)
- Peijie Lv
- The Department of Radiology, The First Affiliated Hospital of Zhengzhou University, No.1, East Jianshe Road, Zhengzhou, Henan Province, China, 450052
| | - Jie Liu
- The Department of Radiology, The First Affiliated Hospital of Zhengzhou University, No.1, East Jianshe Road, Zhengzhou, Henan Province, China, 450052
| | - Xiaopeng Yan
- The Department of Radiology, The First Affiliated Hospital of Zhengzhou University, No.1, East Jianshe Road, Zhengzhou, Henan Province, China, 450052
| | - Yaru Chai
- The Department of Radiology, The First Affiliated Hospital of Zhengzhou University, No.1, East Jianshe Road, Zhengzhou, Henan Province, China, 450052
| | - Yan Chen
- The Department of Radiology, The First Affiliated Hospital of Zhengzhou University, No.1, East Jianshe Road, Zhengzhou, Henan Province, China, 450052
| | - Jianbo Gao
- The Department of Radiology, The First Affiliated Hospital of Zhengzhou University, No.1, East Jianshe Road, Zhengzhou, Henan Province, China, 450052.
| | - Yuanwei Pan
- The Department of Radiology, The First Affiliated Hospital of Zhengzhou University, No.1, East Jianshe Road, Zhengzhou, Henan Province, China, 450052
| | - Shuai Li
- The Department of Radiology, The First Affiliated Hospital of Zhengzhou University, No.1, East Jianshe Road, Zhengzhou, Henan Province, China, 450052
| | - Hua Guo
- The Department of Radiology, The First Affiliated Hospital of Zhengzhou University, No.1, East Jianshe Road, Zhengzhou, Henan Province, China, 450052
| | - Yue Zhou
- The Department of Radiology, The First Affiliated Hospital of Zhengzhou University, No.1, East Jianshe Road, Zhengzhou, Henan Province, China, 450052
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Feng Q, Li Q, Hu Y, Wang QX, Hu DY, Li Z. Small colorectal cancer liver metastases: Clinical value of quantitative iodine-based material decomposition images of spectral CT. Shijie Huaren Xiaohua Zazhi 2016; 24:2421-2428. [DOI: 10.11569/wcjd.v24.i15.2421] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To retrospectively assess the diagnostic value of quantitative iodine-based material decomposition images of spectral CT in evaluating small liver metastases (<3 cm) from colorectal cancer.
METHODS: Nine hundred and fifteen consecutive patients with liver lesions were recruited, and 140 of them were confirmed to have metastatic liver cancer. All the patients underwent double-phase [arterial phase (AP) and portal venous phase (PVP)] spectral CT scans and the best single energy images were obtained at the workstation. Fifteen different sources of small metastatic liver lesions (<3 cm) were analyzed, and the diagnosis rate was compared between the best single energy images and traditional images. The final study group included 41 patients with hepatic metastases from colorectal cancer. Iodine concentrations and CT values of normal liver parenchyma and metastatic lesions were derived from iodine-based material-decomposition CT or conventional CT images. The differences in iodine concentration and CT values between the AP and PVP were recorded and the lesion-to-normal liver parenchyma differences were calculated. The paired t-test was employed to compare CT value and iodine concentrations between AP and PVP. Two readers qualitatively assessed lesion types on the basis of conventional CT characteristics. The two-sample t-test was performed to compare the iodine concentrations and CT values changes between AP and PVP in normal liver parenchyma and metastatic lesions (central and marginal).
RESULTS: Compared with traditional CT hybrid energy images, the detection rate of small metastases was much higher by spectral CT images (Wilcoxon sighed-rank test Z = 3.306, P = 0.001). In the AP, comparing the marginal with the central parts of the lesions, the CT values increased by 37.65% while the iodine value increased by 65.95%, and there was a significant difference between them (P < 0.001). Comparing normal liver tissues with the marginal parts of the lesions, the CT values increased by 22.99% while the iodine value increased by 17.96%, and there was no significant difference between them (P = 0.225). In the PVP, comparing the marginal with the central parts of the lesions, the CT values increased by 32.13% while the iodine value increased by 40.01%, and the difference was significant (P < 0.001). Comparing normal liver tissues with the marginal parts of the lesions, the CT values increased by 34.47% while the iodine value increased by 40.92%, and the difference was significant (P = 0.033).
CONCLUSION: Quantitative CT iodine value analysis may be able to improve the detection rate of small lesions, and it can display the enhancement features of colorectal cancer liver metastases. This technique may help to improve the diagnostic accuracy of small metastatic lesions.
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Dual-energy CT-based iodine quantification for differentiating pulmonary artery sarcoma from pulmonary thromboembolism: a pilot study. Eur Radiol 2015; 26:3162-70. [PMID: 26638163 DOI: 10.1007/s00330-015-4140-2] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2015] [Revised: 11/23/2015] [Accepted: 11/24/2015] [Indexed: 01/24/2023]
Abstract
OBJECTIVES The purpose of this study was to determine whether dual-energy computed tomography (DECT) angiography could differentiate pulmonary thromboembolism (PTE) from pulmonary artery sarcoma (PAS). METHODS We prospectively enrolled 19 patients that had a filling defect in the main pulmonary artery on DECT. Six patients who had PAS and underwent DECT were retrospectively enrolled for comparison. Pathological results or follow-up CT after anticoagulation therapy were used to make the final diagnosis. Two investigators measured the following parameters at the filling defect in the main pulmonary artery: CT attenuation density [Hounsfield units (HU)], iodine-related HU (IHU) and iodine concentration (IC, mg/ml). RESULTS From a total of 25 patients (M:F = 10:15; mean age, 65 years old), 19 were categorised into the PTE group and six were categorised into the PAS group. The mean HU values were not significantly different between the PTE and PAS groups (45.5 ± 15.9 vs 47.1 ± 9.2 HU; P = 0.776). However, the mean IHU and IC values of the lesions were significantly different between the PTE and PAS groups (10.6 ± 7.2 vs 27.9 ± 9.1 HU; P = 0.004, and 0.61 ± 0.39 vs 1.49 ± 0.57; P = 0.001). CONCLUSIONS DECT angiography using a quantitative analytic methodology can be used to differentiate PTE and PAS. KEY POINTS • DECT can be useful for differentiation of PAS and PTE. • With quantitative analysis, DECT offers tissue characterisation by detecting lesion parameter increases. • The patients without predisposing factors for PTE can be candidates for DECT.
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Pancreatic ductal adenocarcinoma and chronic mass-forming pancreatitis: Differentiation with dual-energy MDCT in spectral imaging mode. Eur J Radiol 2015; 84:2470-6. [PMID: 26481480 DOI: 10.1016/j.ejrad.2015.09.023] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2015] [Revised: 09/01/2015] [Accepted: 09/27/2015] [Indexed: 01/26/2023]
Abstract
OBJECTIVE To investigate the value of dual-energy MDCT in spectral imaging in the differential diagnosis of chronic mass-forming chronic pancreatitis (CMFP) and pancreatic ductal adenocarcinoma (PDAC) during the arterial phase (AP) and the pancreatic parenchymal phase (PP). MATERIALS AND METHODS Thirty five consecutive patients with CMFP (n=15) or PDAC (n=20) underwent dual-energy MDCT in spectral imaging during AP and PP. Iodine concentrations were derived from iodine-based material-decomposition CT images and normalized to the iodine concentration in the aorta. The difference in iodine concentration between the AP and PP, contrast-to-noise ratio (CNR) and the slope K of the spectrum curve were calculated. RESULTS Normalized iodine concentrations (NICs) in patients with CMFP differed significantly from those in patients with PDAC during two double phases (mean NIC, 0.26±0.04 mg/mL vs. 0.53±0.02 mg/mL, p=0.0001; 0.07±0.02 mg/mL vs. 0.28±0.04 mg/mL, p=0.0002, respectively). There were significant differences in the value of the slope K of the spectrum curve in two groups during AP and PP (K(CMFP)=3.27±0.70 vs. K(PDAC)=1.35±0.41, P=0.001, and K(CMFP)=3.70±0.17 vs. K(PDAC)=2.16±0.70, p=0.003, respectively). CNRs at low energy levels (40-70 keV) were higher than those at high energy levels (80-40 keV). CONCLUSION Individual patient CNR-optimized energy level images and the NIC can be used to improve the sensitivity and the specificity for differentiating CMFP from PDAC by use of dual-energy MDCT in spectral imaging with fast tube voltage switching.
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Differentiation of low-attenuation intracranial hemorrhage and calcification using dual-energy computed tomography in a phantom system. Invest Radiol 2015; 50:9-16. [PMID: 25162534 DOI: 10.1097/rli.0000000000000089] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVES Calcific and hemorrhagic intracranial lesions with attenuation levels of less than 100 Hounsfield units (HUs) cannot currently be reliably differentiated by single-energy computed tomography (SECT). The proper differentiation of these lesion types would have a multitude of clinical applications. A phantom model was used to test the ability of dual-energy CT (DECT) to differentiate such lesions. MATERIALS AND METHODS Agar gel-bound ferric oxide and hydroxyapatite were used to model hemorrhage and calcification, respectively. Gel models were scanned using SECT and DECT and organized into SECT attenuation-matched pairs at 16 attenuation levels between 0 and 100 HU. Dual-energy CT data were analyzed using 3-dimensional (3D) Gaussian mixture models (GMMs), as well as a simplified threshold plane metric derived from the 3D GMM, to assign voxels to hemorrhagic or calcific categories. Accuracy was calculated by comparing predicted voxel assignments with actual voxel identities. RESULTS We measured 6032 voxels from each gel model, for a total of 193,024 data points (16 matched model pairs). Both the 3D GMM and its more clinically implementable threshold plane derivative yielded similar results, with higher than 90% accuracy at matched SECT attenuation levels of 50 HU and greater. CONCLUSIONS Hemorrhagic and calcific lesions with attenuation levels between 50 and 100 HU were differentiable using DECT in a clinically relevant phantom system with higher than 90% accuracy. This method warrants further testing for potential clinical applications.
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Quantitative Spectral K-Edge Imaging in Preclinical Photon-Counting X-Ray Computed Tomography. Invest Radiol 2015; 50:297-304. [DOI: 10.1097/rli.0000000000000126] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Cai XR, Feng YZ, Qiu L, Xian ZH, Yang WC, Mo XK, Wang XB. Iodine Distribution Map in Dual-Energy Computed Tomography Pulmonary Artery Imaging with Rapid kVp Switching for the Diagnostic Analysis and Quantitative Evaluation of Acute Pulmonary Embolism. Acad Radiol 2015; 22:743-51. [PMID: 25772582 DOI: 10.1016/j.acra.2015.01.012] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2014] [Revised: 01/28/2015] [Accepted: 01/30/2015] [Indexed: 01/01/2023]
Abstract
RATIONALE AND OBJECTIVES To assess the diagnostic value of dual-energy (DE) computed tomography pulmonary angiography (CTPA) for acute pulmonary embolism (PE) using a helical DE scan mode with rapid kVp switching. MATERIALS AND METHODS Seventy-six patients with suspected acute PE underwent DE CTPA. Two readers independently assessed and measured the iodine maps. CTPA images were assessed for the presence, location, and degree of PE as the standard of reference. Iodine maps were used to identify the perfusion defect (PD), and the diagnostic accuracy of iodine maps was calculated. The iodine concentrations of PDs and normal lung parenchyma were also measured and compared. RESULTS A per-patient analysis showed the 84.6% sensitivity and 96.0% specificity of iodine map for PE, and on per-segment analysis, the sensitivity and specificity for PE were 82.9% and 99.6%, respectively. Intraobserver and interobserver variability correlations were excellent, with k values from 0.806 to 1.000. Quantitative analysis showed there was a significant difference for iodine concentration between circumscribed/patchy PDs or wedge-shaped PDs consistent with PE and normal lung parenchyma (P < .05). The intraobserver reliability of reader 1 was from 0.928 to 0.997, and reader 2 was from 0.912 to 0.995. And, the interobserver reliability between two readers was from 0.967 to 0.999. CONCLUSIONS CTPA based on DE scanning with rapid kVp switching can provide both morphologic analysis and quantitative evaluation of PD related to acute PE in addition to standard CTPA data. Quantification of iodine concentration may be helpful for identifying the presence or absence of PE.
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Affiliation(s)
- Xiang-Ran Cai
- Medical Imaging Center, Department of Radiology, The First Affiliated Hospital, Jinan University, No. 613 West Huangpu Ave, Tianhe District, Guangzhou 510630, China
| | - You-Zhen Feng
- Medical Imaging Center, Department of Radiology, The First Affiliated Hospital, Jinan University, No. 613 West Huangpu Ave, Tianhe District, Guangzhou 510630, China
| | - Lin Qiu
- Medical Imaging Center, Department of Radiology, The First Affiliated Hospital, Jinan University, No. 613 West Huangpu Ave, Tianhe District, Guangzhou 510630, China
| | - Zhao-Hui Xian
- Medical Imaging Center, Department of Radiology, The First Affiliated Hospital, Jinan University, No. 613 West Huangpu Ave, Tianhe District, Guangzhou 510630, China
| | - Wen-Cai Yang
- Medical Imaging Center, Department of Radiology, The First Affiliated Hospital, Jinan University, No. 613 West Huangpu Ave, Tianhe District, Guangzhou 510630, China
| | - Xu-Kai Mo
- Medical Imaging Center, Department of Radiology, The First Affiliated Hospital, Jinan University, No. 613 West Huangpu Ave, Tianhe District, Guangzhou 510630, China
| | - Xiao-Bai Wang
- Medical Imaging Center, Department of Radiology, The First Affiliated Hospital, Jinan University, No. 613 West Huangpu Ave, Tianhe District, Guangzhou 510630, China.
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Clinical value of spectral CT in diagnosis of negative gallstones and common bile duct stones. ACTA ACUST UNITED AC 2015; 40:1587-94. [DOI: 10.1007/s00261-015-0387-y] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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Hou WS, Wu HW, Yin Y, Cheng JJ, Zhang Q, Xu JR. Differentiation of lung cancers from inflammatory masses with dual-energy spectral CT imaging. Acad Radiol 2015; 22:337-44. [PMID: 25491737 DOI: 10.1016/j.acra.2014.10.004] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2014] [Revised: 10/07/2014] [Accepted: 10/08/2014] [Indexed: 12/21/2022]
Abstract
RATIONALE AND OBJECTIVES To investigate the value of dual-energy spectral computed tomography (DESCT) in the quantitative differentiation between pulmonary malignant masses and inflammatory masses. MATERIALS AND METHODS This study was an institutional review board-approved study, and written informed consent was obtained from all patients. Sixty patients with 35 lung cancers and 25 inflammatory masses underwent DESCT scan during arterial phase (AP) and venous phase (VP). CT numbers of net enhancement in 70 keV monochromatic images in central and peripheral regions of masses and their differences (dCT) were measured. Iodine concentrations in the two regions were measured and normalized to the aorta as normalized iodine concentrations (NICs). The slopes of spectral attenuation curves (λHU) in the two regions were also calculated. The two-sample t test was used to compare quantitative parameters. Receiver operating characteristic (ROC) curves were generated to calculate sensitivity and specificity. RESULTS CT numbers of net enhancement and NICs in central regions, and λHU values both in the central and peripheral region of lung cancers were significantly lower than those of inflammatory masses during AP and VP. On the other hand, the dCT values of lung cancers were higher than that of inflammatory masses. NIC value in the central regions in VP had the highest sensitivity (86%) and specificity (100%) in differentiating malignant masses from inflammatory masses. CONCLUSIONS DESCT imaging with quantitative parameters such as CT numbers of 70 keV monochromatic images, NIC, and λHU may be a new method for differentiating lung cancers from inflammatory masses.
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Recent Technological Advances in Computed Tomography and the Clinical Impact Therein. Invest Radiol 2015; 50:119-27. [DOI: 10.1097/rli.0000000000000125] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Liu WD, Wu XW, Hu JM, Wang B, Liu B. Monochromatic energy computed tomography image for active intestinal hemorrhage: A model investigation. World J Gastroenterol 2015; 21:214-220. [PMID: 25574093 PMCID: PMC4284337 DOI: 10.3748/wjg.v21.i1.214] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/20/2014] [Revised: 07/31/2014] [Accepted: 09/16/2014] [Indexed: 02/06/2023] Open
Abstract
AIM: To investigate the value of computed tomography (CT) spectral imaging in the evaluation of intestinal hemorrhage.
METHODS: Seven blood flow rates were simulated in vitro. Energy spectral CT and mixed-energy CT scans were performed for each rate (0.5, 0.4, 0.3, 0.2, 0.1, 0.05 and 0.025 mL/min). The detection rates and the contrast-to-noise ratios (CNRs) of the contrast agent extravasation regions were compared between the two scanning methods in the arterial phase (AP) and the portal venous phase (PVP). Comparisons of the CNR values between the PVP and the AP were made for each energy level and carried out using a completely random t test. A χ2 test was used to compare the detection rates obtained from the two scanning methods.
RESULTS: The total detection rates for energy spectral CT and mixed-energy CT in the AP were 88.57% (31/35) and 65.71% (23/35), respectively, and the difference was significant (χ2 = 5.185, P = 0.023); the total detection rates in the PVP were 100.00% (35/35) and 91.4% (32/35), respectively, and the difference was not significant (χ2 = 1.393, P = 0.238). In the AP, the CNR of the contrast agent extravasation regions was 3.58 ± 2.09 on the mixed-energy CT images, but the CNRs were 8.78 ± 7.21 and 8.83 ± 6.75 at 50 and 60 keV, respectively, on the single-energy CT images, which were significantly different (3.58 ± 2.09 vs 8.78 ± 7.21, P = 0.031; 3.58 ± 2.09 vs 8.83 ± 6.75, P = 0.029). In the PVP, the differences between the CNRs at 40, 50 and 60 keV different monochromatic energy levels and the polychromatic energy images were significant (19.35 ± 10.89 vs 11.68 ± 6.38, P = 0.010; 20.82 ± 11.26 vs 11.68 ± 6.38, P = 0.001; 20.63 ± 10.07 vs 11.68 ± 6.38, P = 0.001). The CNRs at the different energy levels in the AP and the PVP were significantly different (t = -2.415, -2.380, -2.575, -2.762, -2.945, -3.157, -3.996 and -3.189).
CONCLUSION: Monochromatic energy imaging spectral CT is superior to polychromatic energy images for the detection of intestinal hemorrhage, and the detection was easier in the PVP compared with the AP.
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Hu S, Huang W, Chen Y, Song Q, Lin X, Wang Z, Chen K. Spectral CT evaluation of interstitial brachytherapy in pancreatic carcinoma xenografts: preliminary animal experience. Eur Radiol 2014; 24:2167-73. [PMID: 24903229 DOI: 10.1007/s00330-014-3257-z] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2013] [Revised: 05/05/2014] [Accepted: 05/21/2014] [Indexed: 12/11/2022]
Abstract
OBJECTIVES We sought to evaluate the capability of spectral CT to detect the therapeutic response to (125)I interstitial brachytherapy in a pancreatic carcinoma xenograft nude mouse model. METHODS Twenty mice bearing SWl990 human pancreatic cancer cell xenografts were randomly separated into two groups: experimental (n = 10; 1.0 mCi) and control (n = 10; 0 mCi). After a two-week treatment, spectral CT was performed. Contrast-to-noise ratio (CNR) and iodine concentration (IC) in the lesions were measured and normalized to the muscle tissue, and nIC CD31 immunohistochemistry was used to measure microvessel density (MVD). The relationships between the nIC and MVD of the tumours were analysed. RESULTS The nIC of the experimental group was significantly lower than that of the control group during the multiphase examination. A significant difference in the MVD was observed between the two groups (P <0.001). The nIC values of the three-phase scans have a certain positive correlation with MVD (r = 0.57, p < 0.0001; r = 0.48, p = 0.002; r = 0.63, p = 0.0017 in the 10, 25, and 60 s phase, respectively). CONCLUSIONS Spectral CT can be a useful non-invasive imaging modality in evaluating the therapeutic effect of (125)I interstitial brachytherapy to a pancreatic carcinoma. KEY POINTS Spectral CT offers opportunities to assess therapeutic response in pancreatic cancer cases. Spectral CT findings correlated with vascular changes associated with (125)I seed implantation. Spectral CT with monochromatic imaging removed most (125)I seed artefacts.
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Affiliation(s)
- Shudong Hu
- Department of Radiology, The Affiliated Renmin Hospital, Jiangsu University, Zhenjiang, Jiangsu, 212002, China,
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Kim SS, Hur J, Kim YJ, Lee HJ, Hong YJ, Choi BW. Dual-energy CT for differentiating acute and chronic pulmonary thromboembolism: an initial experience. Int J Cardiovasc Imaging 2014; 30 Suppl 2:113-20. [PMID: 25096053 DOI: 10.1007/s10554-014-0508-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/24/2014] [Accepted: 07/25/2014] [Indexed: 12/16/2022]
Abstract
The purpose of this study was to prospectively evaluate the diagnostic capability of single-phase dual-energy CT (DECT) angiography to differentiate acute and chronic pulmonary thromboembolism (APTE, CPTE). We prospectively enrolled 26 patients (M:F = 9:17; mean age, 61 years old) with a filling defect in the pulmonary artery on DECT angiography. They were divided into two groups-APTE and CPTE-based on the clinical criteria. Two investigators quantitatively measured the following parameters at the embolism and main pulmonary artery: CT attenuation density [Hounsfield unit (HU) values], iodine-related HU value (IHU), and iodine concentration (IC, mg/ml). These parameters of the embolism and their ratio divided by those of the main pulmonary artery were compared between APTE and CPTE groups. Among 26 patients, 15 were categorized into the APTE group and 11 into the CPTE group. The mean HU, IHU, and IC values of emboli were significantly different between the APTE and CPTE groups (32.2 ± 17.0 vs. 52.1 ± 13.6 HU; P = 0.016, 7.2 ± 2.8 vs. 27.3 ± 12.7 HU; P < 0.001, and 0.57 ± 0.23 vs. 1.56 ± 0.67; P < 0.001). The mean HU, IHU, and IC ratios between emboli and main pulmonary arteries were also significantly different between the two groups (0.085 ± 0.046 vs. 0.156 ± 0.064 HU; P = 0.003, 0.023 ± 0.013 vs. 0.099 ± 0.053; P < 0.001, and 0.048 ± 0.035 vs. 0.130 ± 0.064; P = 0.001). DECT angiography using a quantitative analytic methodology can be used to differentiate between APTE and CPTE.
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Affiliation(s)
- Seung-Seob Kim
- Department of Radiology, Research Institute of Radiological Science, Severance Hospital, Yonsei University College of Medicine, 50 Yonsei-ro, Seodaemun-gu, Seoul, 120-752, South Korea
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Hu D, Yu T, Duan X, Peng Y, Zhai R. Determination of the optimal energy level in spectral CT imaging for displaying abdominal vessels in pediatric patients. Eur J Radiol 2014; 83:589-94. [DOI: 10.1016/j.ejrad.2013.10.016] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2013] [Revised: 10/07/2013] [Accepted: 10/15/2013] [Indexed: 10/26/2022]
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Effectiveness of Automated Quantification of Pulmonary Perfused Blood Volume Using Dual-Energy CTPA for the Severity Assessment of Acute Pulmonary Embolism. Invest Radiol 2013; 48:563-9. [DOI: 10.1097/rli.0b013e3182879482] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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Optimal monochromatic energy levels in spectral CT pulmonary angiography for the evaluation of pulmonary embolism. PLoS One 2013; 8:e63140. [PMID: 23667583 PMCID: PMC3646731 DOI: 10.1371/journal.pone.0063140] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2013] [Accepted: 03/29/2013] [Indexed: 11/19/2022] Open
Abstract
Background The aim of this study was to determine the optimal monochromatic spectral CT pulmonary angiography (sCTPA) levels to obtain the highest image quality and diagnostic confidence for pulmonary embolism detection. Methods The Institutional Review Board of the Shanghai Jiao Tong University School of Medicine approved this study, and written informed consent was obtained from all participating patients. Seventy-two patients with pulmonary embolism were scanned with spectral CT mode in the arterial phase. One hundred and one sets of virtual monochromatic spectral (VMS) images were generated ranging from 40 keV to 140 keV. Image noise, clot diameter and clot to artery contrast-to-noise ratio (CNR) from seven sets of VMS images at selected monochromatic levels in sCTPA were measured and compared. Subjective image quality and diagnostic confidence for these images were also assessed and compared. Data were analyzed by paired t test and Wilcoxon rank sum test. Results The lowest noise and the highest image quality score for the VMS images were obtained at 65 keV. The VMS images at 65 keV also had the second highest CNR value behind that of 50 keV VMS images. There was no difference in the mean noise and CNR between the 65 keV and 70 keV VMS images. The apparent clot diameter correlated with the keV levels. Conclusions The optimal energy level for detecting pulmonary embolism using dual-energy spectral CT pulmonary angiography was 65–70 keV. Virtual monochromatic spectral images at approximately 65–70 keV yielded the lowest image noise, high CNR and highest diagnostic confidence for the detection of pulmonary embolism.
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Abstract
OBJECTIVE The introduction of dual-energy CT (DECT) has ushered in the ability of material differentiation and tissue characterization beyond the traditional CT attenuation scale. This quality has been exploited for visualizing and quantifying the specific tissue content using radiographic contrast agents, such as iodine-based contrast media or inhaled xenon gas. Applications of this paradigm in the thorax include characterization of the pulmonary blood pool in the setting of acute or chronic pulmonary embolism (PE) and characterization of diseases of the lung parenchyma. Selective xenon detection is being explored for imaging of lung ventilation. In addition, the usefulness of DECT-based selective iodine uptake measurements has been described for the diagnosis and surveillance of thoracic malignancies. This article reviews the current applications of DECT-based imaging techniques in the chest with an emphasis on the diagnosis and characterization of pulmonary thromboembolic disorders. CONCLUSION DECT can provide both anatomic and functional information about the lungs in a variety of pulmonary disease states based on a single contrast-enhanced CT examination. This quality has been shown to improve the diagnosis of acute and chronic PEs, other vascular disorders, lung malignancies, and parenchymal diseases. Further developments in DECT techniques and CT scanner technology will further foster and enhance the utility of this application and open new avenues in lung imaging.
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