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Rezaei-Kalantari K, Samimi K, Zomorodian H, Bakhshandeh H, Jafari M, Farahmand AM, Pourseyedian T, Sharifian M, Qanadli SD. Pulmonary Blood Volume Measured by Dual-Energy Computed Tomography Can Help Distinguish Patients With Pulmonary Hypertension. Front Cardiovasc Med 2022; 9:835655. [PMID: 35865383 PMCID: PMC9294319 DOI: 10.3389/fcvm.2022.835655] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Accepted: 06/01/2022] [Indexed: 11/18/2022] Open
Abstract
Purpose To evaluate the correlation between whole lung enhancement (WLE) and pulmonary blood volume (PBV) obtained through dual energy computed tomography pulmonary angiography (DECTPA) and echocardiography-derived systolic pulmonary arterial pressure (SPAP). Methods Sixty-eight patients who underwent DECTPA were enrolled in the study after giving informed consent. A transthoracic echocardiography was performed for all the subjects within 48 h of their DECTPA study to measure SPAP. The correlation of the two DECTPA-derived parameters, WLE and PBV, with SPAP was assessed. In addition, the predictive strength of these parameters was compared with that of traditional computed tomography (CT) signs of pulmonary hypertension (PH). Results The SPAP value showed a moderate correlation with main pulmonary artery (MPA) diameter (r = 0.48, P < 0.001), while having a weak correlation with WLE (r = −0.33, P = 0.007), PBV (r = −0.31, P = 0.01) and MPA/ascending aorta (MPA/AA) ratio (r = 0.26, P = 0.03). On regression analysis, MPA diameter (B ± SE: 1.8 ± 0.6, P = 0.004) and WLE (B ± SE: −0.5 ± 0.3, P = 0.042) had significant association with SPAP. In addition, SPAP ≥30 mmHg was related to the right to left ventricular diameter (RV/LV) ratio [OR (CI 95%): 24.39 (1.3–573.2), P = 0.04] and reversely associated with PBV [OR (CI 95%): 0.96 (0.93–0.98), P = 0.005]. Acquired cutoff value of 83% for PBV showed sensitivity and specificity of 73% to identify SPAP ≥30 mmHg [AUC (CI 95%):0.727 (0.588–0.866), P = 0.008]. Conclusions Automated postprocessing calculation of iodine distribution analysis by DECTPA could be considered as an adjunctive tool to investigate for PH.
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Affiliation(s)
- Kiara Rezaei-Kalantari
- Rajaei Cardiovascular Medical and Research Center, Iran University of Medical Sciences, Tehran, Iran
- Cardio-Oncology Research Center, Rajaei Cardiovascular Medical and Research Center, Iran University of Medical Sciences, Tehran, Iran
| | - Kaveh Samimi
- Hazrat Rasoul-e-Akram Hospital, Iran University of Medical Sciences, Tehran, Iran
| | - Hamid Zomorodian
- Department of Radiology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Hooman Bakhshandeh
- Rajaei Cardiovascular Medical and Research Center, Iran University of Medical Sciences, Tehran, Iran
| | - Maryam Jafari
- Department of Radiology, Ali Asghar Children Hospital, Iran University of Medical Sciences, Tehran, Iran
| | | | - Taleb Pourseyedian
- Rajaei Cardiovascular Medical and Research Center, Iran University of Medical Sciences, Tehran, Iran
| | - Maedeh Sharifian
- Rajaei Cardiovascular Medical and Research Center, Iran University of Medical Sciences, Tehran, Iran
- *Correspondence: Maedeh Sharifian
| | - Salah Dine Qanadli
- Cardiothoracic and Vascular Division, Department of Diagnostic and Interventional Radiology, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland
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Diagnostic Impact of Quantitative Dual-Energy Computed Tomography Perfusion Imaging for the Assessment of Subsegmental Pulmonary Embolism. J Comput Assist Tomogr 2021; 45:151-156. [PMID: 33186173 DOI: 10.1097/rct.0000000000001106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
OBJECTIVE The aim of this study was to investigate the quantitative differences of dual-energy computed tomography perfusion imaging measurements in subsegmental pulmonary embolism (SSPE), between normal lung parenchyma (NLP) and hypoperfused segments (HPS) with and without thrombus on computed tomography angiography (CTA). METHODS Lung attenuation, iodine density, and normalized uptake values were measured from HPS and NLP on iodine maps of 43 patients with SSPE. Presence of pulmonary embolism (PE) on CTA was recorded. One-way repeated-measures analysis of variance and Kruskal-Wallis analyses with post hoc comparisons were conducted. RESULTS The numbers of HPS with and without SSPE on CTA were 45 (55.6%) and 36 (44.4%), respectively. Lung attenuation of NLP was significantly different from HPS (P < 0.001). Iodine density and normalized uptake values of HPS with PE were significantly lower than those of HPS without PE, which is significantly lower than NLP (P < 0.001). CONCLUSIONS Subsegmental pulmonary embolism causes HPS on dual-energy computed tomography perfusion imaging, which demonstrates different iodine density and normalized uptake values depending on the presence of thrombus.
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Radiological differences between chronic thromboembolic pulmonary disease (CTEPD) and chronic thromboembolic pulmonary hypertension (CTEPH). Eur Radiol 2021; 31:6230-6238. [PMID: 33507354 PMCID: PMC8270867 DOI: 10.1007/s00330-020-07556-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2020] [Revised: 09/26/2020] [Accepted: 11/06/2020] [Indexed: 12/12/2022]
Abstract
OBJECTIVES The aim of this study was to describe the radiological features of chronic thromboembolic pulmonary disease (CTEPD), not yet systematically described in the literature. Furthermore, we compared vascular scores between CTEPD and chronic thromboembolic pulmonary hypertension (CTEPH) patients, trying to explain why pulmonary hypertension does not develop at rest in CTEPD patients. METHODS Eighty-five patients (40 CTEPD, 45 CTEPH) referred to our centre for pulmonary endarterectomy underwent dual-energy computed tomography pulmonary angiography (DE-CTPA) with iodine perfusion maps; other 6 CTEPD patients underwent single-source CTPA. CT scans were reviewed independently by an experienced cardiothoracic radiologist and a radiology resident to evaluate scores of vascular obstruction, hypoperfusion and mosaic attenuation, signs of pulmonary hypertension and other CT features typical of CTEPH. RESULTS Vascular obstruction burden was similar in the two groups (p = 0.073), but CTEPD patients have a smaller extension of perfusion defects in the iodine map (p = 0.009) and a smaller number of these patients had mosaic attenuation (p < 0.001) than CTEPH patients, suggesting the absence of microvascular disease. Furthermore, as expected, the two groups were significantly different considering the indirect signs of pulmonary hypertension (p < 0.001). CONCLUSIONS CTEPD and CTEPH patients have significantly different radiological characteristics, in terms of signs of pulmonary hypertension, mosaic attenuation and iodine map perfusion extension. Importantly, our results suggest that the absence of peripheral microvascular disease, even in presence of an important thrombotic burden, might be the reason for the absence of pulmonary hypertension in CTEPD. KEY POINTS • CTEPD and CTEPH patients have significantly different radiological characteristics. • The absence of peripheral microvascular disease might be the reason for the absence of pulmonary hypertension in CTEPD.
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Johns CS, Wild JM, Rajaram S, Swift AJ, Kiely DG. Current and emerging imaging techniques in the diagnosis and assessment of pulmonary hypertension. Expert Rev Respir Med 2019; 12:145-160. [PMID: 29261337 DOI: 10.1080/17476348.2018.1420478] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
INTRODUCTION Pulmonary hypertension (PH) is a challenging condition to diagnose and treat. Over the last two decades, there have been significant advances in therapeutic approaches and imaging technologies. Current guidelines emphasize the importance of cardiac catheterization; however, the increasing availability of non-invasive imaging has the potential to improve diagnostic rates, whilst providing additional information on patient phenotypes. Areas covered: This review discusses the role of imaging in the diagnosis, prognostic assessment and follow-up of patients with PH. Imaging methods, ranging from established investigations (chest radiography, echocardiography, nuclear medicine and computerized tomography (CT)), to emerging modalities (dual energy CT, magnetic resonance imaging (MRI), optical coherence tomography and positron emission tomography (PET)) are reviewed. The value and limitations of the clinical utility of these imaging modalities and their potential clinical application are reviewed. Expert commentary: Imaging plays a key role in the diagnosis and classification of pulmonary hypertension. It also provides valuable prognostic information and emerging evidence supports a role for serial assessments. The authors anticipate an increasing role for imaging in the pulmonary hypertension clinic. This will reduce the need for invasive investigations, whilst providing valuable insights that will improve our understanding of disease facilitate a more targeted approach to treatment.
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Affiliation(s)
| | - Jim M Wild
- a Academic Radiology , The University of Sheffield , Sheffield , UK
| | - Smitha Rajaram
- b Sheffield Pulmonary Vascular Disease Unit , Sheffield Teaching Hospitals , Sheffield , UK
| | - Andy J Swift
- a Academic Radiology , The University of Sheffield , Sheffield , UK
| | - David G Kiely
- b Sheffield Pulmonary Vascular Disease Unit , Sheffield Teaching Hospitals , Sheffield , UK
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Bankier AA, Dennie C. Modern Diagnosis in the Evaluation of Pulmonary Vascular Disease. IDKD SPRINGER SERIES 2019. [DOI: 10.1007/978-3-030-11149-6_17] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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Value of Dual-Energy Computed Tomography for Diagnosing Cervical Lymph Node Metastasis in Patients With Papillary Thyroid Cancer. J Comput Assist Tomogr 2019; 43:970-975. [DOI: 10.1097/rct.0000000000000927] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Chen ML, Li XT, Wei YY, Qi LP, Sun YS. Can spectral computed tomography imaging improve the differentiation between malignant and benign pulmonary lesions manifesting as solitary pure ground glass, mixed ground glass, and solid nodules? Thorac Cancer 2018; 10:234-242. [PMID: 30582292 PMCID: PMC6360238 DOI: 10.1111/1759-7714.12937] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Revised: 11/18/2018] [Accepted: 11/19/2018] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND This study quantitatively assessed the efficacy of spectral computed tomography (CT) imaging parameters for differentiating the malignancy and benignity of solitary pulmonary nodules (SPNs) manifesting as ground glass nodules (GGNs) and solid nodules (SNs). METHODS The study included 114 patients with SPNs (61 GGNs, and 53 SNs) who underwent CT plain and enhanced scans in the arterial (a) and venous (v) phases using the spectral imaging mode. The spectral CT imaging parameters included: iodine concentrations (IC) of lesions in the arterial (ICLa) and venous (ICLv) phases; normalized IC (NICa/NICv, normalized to the IC in the aorta); the slope of the spectral Hounsfield unit (HU) curve (λHUa/λHUv); and monochromatic CT number (CT40keVa/v, CT70keVa/v) enhancement on 40 and 70 keV images. The two-sample Mann-Whitney U test was used to compare quantitative parameters between malignant and benign SPNs, SNs, and GGNs. RESULTS Pathology revealed 75 lung cancer cases, 3 metastatic nodules, 14 benign nodules, and 22 inflammatory nodules. Among the 53 SNs there were 37 malignant and 16 benign nodules. Among the 61 GGNs there were 41 malignant and 20 benign nodules. Overall, the CT40keVa, λHUa, CT40keVv, λHUv, and ICLv of benign SPNs were all greater than those of malignant SPNs (all P < 0.05). For GGNs, CT40keVa/v, CT70keVa/v, λHUa/λHUv, and ICLv of malignant GGNs were all lower than those of benign GGNs. CONCLUSION Spectral CT imaging is a more promising method for distinguishing malignant from benign nodules, especially in nodules manifesting as GGNs in contrast-enhanced scanning.
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Affiliation(s)
- Mai-Lin Chen
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Department of Radiology, Peking University Cancer Hospital & Institute, Beijing, China
| | - Xiao-Ting Li
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Department of Radiology, Peking University Cancer Hospital & Institute, Beijing, China
| | - Yi-Yuan Wei
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Department of Radiology, Peking University Cancer Hospital & Institute, Beijing, China
| | - Li-Ping Qi
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Department of Radiology, Peking University Cancer Hospital & Institute, Beijing, China
| | - Ying-Shi Sun
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Department of Radiology, Peking University Cancer Hospital & Institute, Beijing, China
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Jiang H, Li X. Correlation of dual-source computed tomography/dual-energy imaging with pathological grading of lung adenocarcinoma and its clinical value. Pak J Med Sci 2017; 33:1429-1433. [PMID: 29492072 PMCID: PMC5768838 DOI: 10.12669/pjms.336.13320] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Objective: To explore the correlation of dual-source computed tomography (DSCT)/dual-energy imaging with pathological grading of lung adenocarcinoma. Methods: A total of 47 patients with lung adenocarcinoma were selected. Tissues were histopathologically confirmed by routine DSCT scanning and dual-energy enhanced scanning. Arterial-phase and venous-phase iodine distribution images and single-energy images at 40-190 keV were obtained. The region of interest was outlined to obtain CT values. The iodine concentrations of each tumor in two phases were recorded to calculate normalized iodine concentrations (NICs). Results: The maximum diameter and minimum diameter of tumors in low differentiation (LD) group were significantly higher than those of high differentiation (HD) group (P<0.05). In LD group, 70.8% of margins were lobulated, which significantly exceeded that of HD group (30.4%) (P<0.05). Besides, 26.1% of patients in HD group were complicated with ground-glass opacity, which was significantly higher than that of LD group (4.2%) (P<0.05). In venous phase, there were significant differences between the two groups at low energy levels (40-70 keV) (P<0.05). At high energy levels (80-190 keV), the CT values of LD group were slightly higher than those of HD group. In arterial and venous phases, NICs of HD group were lower than those of LD group (P>0.05). Conclusion: HD and LD groups could be predictably distinguished by single-energy images at low energy levels (40-70 keV) in the venous phase. Quantitative analysis of NIC in the venous phase is also valuable for predicting the pathological grade of lung adenocarcinoma.
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Affiliation(s)
- Haifeng Jiang
- Haifeng Jiang, Department of Radiology, Gansu Provincial Hospital, Lanzhou 730000, People's Republic of China
| | - Xiao Li
- Xiao Li, Department of Radiology, Gansu Provincial Hospital, Lanzhou 730000, People's Republic of China
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Felloni P, Duhamel A, Faivre JB, Giordano J, Khung S, Deken V, Remy J, Remy-Jardin M. Regional Distribution of Pulmonary Blood Volume with Dual-Energy Computed Tomography: Results in 42 Subjects. Acad Radiol 2017; 24:1412-1421. [PMID: 28711443 DOI: 10.1016/j.acra.2017.05.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2016] [Revised: 04/27/2017] [Accepted: 05/10/2017] [Indexed: 10/19/2022]
Abstract
RATIONALE AND OBJECTIVES The noninvasive approach of lung perfusion generated from dual-energy computed tomography acquisitions has entered clinical practice. The purpose of this study was to analyze the regional distribution of iodine within distal portions of the pulmonary arterial bed on dual-source, dual-energy computed tomography examinations in a cohort of subjects without cardiopulmonary pathologies. MATERIALS AND METHODS The study population included 42 patients without cardiorespiratory disease, enabling quantitative and qualitative analysis of pulmonary blood volume after administration of a 40% contrast agent. Qualitative analysis was based on visual assessment. Quantitative analysis was obtained after semiautomatic division of each lung into 18 areas. RESULTS The iodine concentration did not significantly differ between the right (R) and left (L) lungs (P = .49), with a mean attenuation of 41.35 Hounsfield units (HU) and 41.14 HU, respectively. Three regional gradients of attenuation were observed between: (a) lung bases and apices (P < .001), linked to the conditions of examination (mean Δ: 6.23 in the R lung; 5.96 in the L lung); (b) posterior and anterior parts of the lung (P < .001) due to gravity (mean Δ: 11.92 in the R lung ; 15.93 in the L lung); and (c) medullary and cortical lung zones (P < .001) (mean Δ: 9.35 in the R lung ; 8.37 in the L lung). The intensity of dependent-nondependent (r = 0.42; P < .001) and corticomedullary (r = 0.58; P < .0001) gradients was correlated to the overall iodine concentration. CONCLUSION Distribution of pulmonary blood volume is influenced by physiological gradients and scanning conditions.
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10
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White Paper of the Society of Computed Body Tomography and Magnetic Resonance on Dual-Energy CT, Part 3. J Comput Assist Tomogr 2017; 41:1-7. [DOI: 10.1097/rct.0000000000000538] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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11
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Tilve-Gómez A, Rodríguez-Fernández P, Trillo-Fandiño L, Plasencia-Martínez JM. Imaging techniques used in the diagnostic workup of acute venous thromboembolic disease. RADIOLOGIA 2016; 59:329-342. [PMID: 27986265 DOI: 10.1016/j.rx.2016.10.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Revised: 09/09/2016] [Accepted: 10/24/2016] [Indexed: 10/20/2022]
Abstract
Early diagnosis is one of the most important factors affecting the prognosis of pulmonary embolism (PE); however, the clinical presentation of PE is often very unspecific and it can simulate other diseases. For these reasons, imaging tests, especially computed tomography angiography (CTA) of the pulmonary arteries, have become the keystone in the diagnostic workup of PE. The wide availability and high diagnostic performance of pulmonary CTA has led to an increase in the number of examinations done and a consequent increase in the population's exposure to radiation and iodinated contrast material. Thus, other techniques such as scintigraphy and venous ultrasonography of the lower limbs, although less accurate, continue to be used in certain circumstances, and optimized protocols have been developed for CTA to reduce the dose of radiation (by decreasing the kilovoltage) and the dose of contrast agents. We describe the technical characteristics and interpretation of the findings for each imaging technique used to diagnose PE and discuss their advantages and limitations; this knowledge will help the best technique to be chosen for each case. Finally, we comment on some data about the increased use of CTA, its clinical repercussions, its "overuse", and doubts about its cost-effectiveness.
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Affiliation(s)
- A Tilve-Gómez
- Servicio de Radiodiagnóstico, IISGS, XXIV, Hospital Álvaro Cunqueiro, Vigo (Pontevedra), España.
| | - P Rodríguez-Fernández
- Servicio de Radiodiagnóstico, IISGS, XXIV, Hospital Álvaro Cunqueiro, Vigo (Pontevedra), España
| | - L Trillo-Fandiño
- Servicio de Radiodiagnóstico, IISGS, XXIV, Hospital Álvaro Cunqueiro, Vigo (Pontevedra), España
| | - J M Plasencia-Martínez
- Servicio de Radiodiagnóstico, Hospital General Universitario José María Morales Meseguer, Murcia, España
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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: 1.3] [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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Taslakian B, Latson LA, Truong MT, Aaltonen E, Shiau MC, Girvin F, Alpert JB, Wickstrom M, Ko JP. CT pulmonary angiography of adult pulmonary vascular diseases: Technical considerations and interpretive pitfalls. Eur J Radiol 2016; 85:2049-2063. [PMID: 27776659 DOI: 10.1016/j.ejrad.2016.09.017] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2016] [Revised: 07/30/2016] [Accepted: 09/15/2016] [Indexed: 12/28/2022]
Abstract
Computed tomography pulmonary angiography (CTPA) has become the primary imaging modality for evaluating the pulmonary arteries. Although pulmonary embolism is the primary indication for CTPA, various pulmonary vascular abnormalities can be detected in adults. Knowledge of these disease entities and understanding technical pitfalls that can occur when performing CTPA are essential to enable accurate diagnosis and allow timely management. This review will cover a spectrum of acquired abnormalities including pulmonary embolism due to thrombus and foreign bodies, primary and metastatic tumor involving the pulmonary arteries, pulmonary hypertension, as well as pulmonary artery aneurysms and stenoses. Additionally, methods to overcome technical pitfalls and interventional treatment options will be addressed.
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Affiliation(s)
| | - Larry A Latson
- Department of Radiology, NYU Langone Medical Center, NY, USA.
| | - Mylene T Truong
- Department of Radiology, University of Texas, MD Anderson Cancer Center, TX, USA.
| | - Eric Aaltonen
- Department of Radiology, NYU Langone Medical Center, NY, USA.
| | - Maria C Shiau
- Department of Radiology, NYU Langone Medical Center, NY, USA.
| | - Francis Girvin
- Department of Radiology, NYU Langone Medical Center, NY, USA.
| | | | - Maj Wickstrom
- Department of Radiology, NYU Langone Medical Center, NY, USA.
| | - Jane P Ko
- Department of Radiology, NYU Langone Medical Center, NY, USA.
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Yazdani M, Lau CT, Lempel JK, Yadav R, El-Sherief AH, Azok JT, Renapurkar RD. Historical Evolution of Imaging Techniques for the Evaluation of Pulmonary Embolism. Radiographics 2016; 35:1245-62. [PMID: 26172362 DOI: 10.1148/rg.2015140280] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
As we celebrate the 100th anniversary of the founding of the Radiological Society of North America (RSNA), it seems fitting to look back at the major accomplishments of the radiology community in the diagnosis of pulmonary embolism. Few diseases have so consistently captured the attention of the medical community. Since the first description of pulmonary embolism by Virchow in the 1850s, clinicians have struggled to reach a timely diagnosis of this common condition because of its nonspecific and often confusing clinical picture. As imaging tests started to gain importance in the 1900s, the approach to diagnosing pulmonary embolism also began to change. Rapid improvements in angiography, ventilation-perfusion imaging, and cross-sectional imaging modalities such as computed tomography (CT) and magnetic resonance imaging have constantly forced health care professionals to rethink how they diagnose pulmonary embolism. Needless to say, the way pulmonary embolism is diagnosed today is distinctly different from how it was diagnosed in Virchow's era; and imaging, particularly CT, now forms the cornerstone of diagnostic evaluation. Currently, radiology offers a variety of tests that are fast and accurate and can provide anatomic and functional information, thus allowing early diagnosis and triage of cases. This review provides a historical journey into the evolution of these imaging tests and highlights some of the major breakthroughs achieved by the radiology community and RSNA in this process. Also highlighted are areas of ongoing research and development in this field of imaging as radiologists seek to combat some of the newer challenges faced by modern medicine, such as rising health care costs and radiation dose hazards.
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Affiliation(s)
- Milad Yazdani
- From the Sections of Thoracic Imaging (M.Y., C.T.L., J.K.L., R.Y., A.H.E., J.T.Z., R.D.R.) and Nuclear Medicine (R.Y., R.D.R.), Imaging Institute, Thoracic Imaging L10, Cleveland Clinic, 9500 Euclid Ave, Cleveland, OH 44195
| | - Charles T Lau
- From the Sections of Thoracic Imaging (M.Y., C.T.L., J.K.L., R.Y., A.H.E., J.T.Z., R.D.R.) and Nuclear Medicine (R.Y., R.D.R.), Imaging Institute, Thoracic Imaging L10, Cleveland Clinic, 9500 Euclid Ave, Cleveland, OH 44195
| | - Jason K Lempel
- From the Sections of Thoracic Imaging (M.Y., C.T.L., J.K.L., R.Y., A.H.E., J.T.Z., R.D.R.) and Nuclear Medicine (R.Y., R.D.R.), Imaging Institute, Thoracic Imaging L10, Cleveland Clinic, 9500 Euclid Ave, Cleveland, OH 44195
| | - Ruchi Yadav
- From the Sections of Thoracic Imaging (M.Y., C.T.L., J.K.L., R.Y., A.H.E., J.T.Z., R.D.R.) and Nuclear Medicine (R.Y., R.D.R.), Imaging Institute, Thoracic Imaging L10, Cleveland Clinic, 9500 Euclid Ave, Cleveland, OH 44195
| | - Ahmed H El-Sherief
- From the Sections of Thoracic Imaging (M.Y., C.T.L., J.K.L., R.Y., A.H.E., J.T.Z., R.D.R.) and Nuclear Medicine (R.Y., R.D.R.), Imaging Institute, Thoracic Imaging L10, Cleveland Clinic, 9500 Euclid Ave, Cleveland, OH 44195
| | - Joseph T Azok
- From the Sections of Thoracic Imaging (M.Y., C.T.L., J.K.L., R.Y., A.H.E., J.T.Z., R.D.R.) and Nuclear Medicine (R.Y., R.D.R.), Imaging Institute, Thoracic Imaging L10, Cleveland Clinic, 9500 Euclid Ave, Cleveland, OH 44195
| | - Rahul D Renapurkar
- From the Sections of Thoracic Imaging (M.Y., C.T.L., J.K.L., R.Y., A.H.E., J.T.Z., R.D.R.) and Nuclear Medicine (R.Y., R.D.R.), Imaging Institute, Thoracic Imaging L10, Cleveland Clinic, 9500 Euclid Ave, Cleveland, OH 44195
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Xiao H, Liu Y, Tan H, Liang P, Wang B, Su L, Wang S, Gao J. A pilot study using low-dose Spectral CT and ASIR (Adaptive Statistical Iterative Reconstruction) algorithm to diagnose solitary pulmonary nodules. BMC Med Imaging 2015; 15:54. [PMID: 26576676 PMCID: PMC4647278 DOI: 10.1186/s12880-015-0096-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2015] [Accepted: 10/25/2015] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Lung cancer is the most common cancer which has the highest mortality rate. With the development of computed tomography (CT) techniques, the case detection rates of solitary pulmonary nodules (SPN) has constantly increased and the diagnosis accuracy of SPN has remained a hot topic in clinical and imaging diagnosis. The aim of this study was to evaluate the combination of low-dose spectral CT and ASIR (Adaptive Statistical Iterative Reconstruction) algorithm in the diagnosis of solitary pulmonary nodules (SPN). METHODS 62 patients with SPN (42 cases of benign SPN and 20 cases of malignant SPN, pathology confirmed) were scanned by spectral CT with a dual-phase contrast-enhanced method. The iodine and water concentration (IC and WC) of the lesion and the artery in the image that had the same density were measured by the GSI (Gemstone Spectral Imaging) software. The normalized iodine and water concentration (NIC and NWC) of the lesion and the normalized iodine and water concentration difference (ICD and WCD) between the arterial and venous phases (AP and VP) were also calculated. The spectral HU (Hounsfield Unit ) curve was divided into 3 sections based on the energy (40-70, 70-100 and 100-140 keV) and the slopes (λHU) in both phases were calculated. The ICAP, ICVP, WCAP and WCVP, NIC and NWC, and the λHU in benign and malignant SPN were compared by independent sample t-test. RESULTS The iodine related parameters (ICAP, ICVP, NICAP, NICVP, and the ICD) of malignant SPN were significantly higher than that of benign SPN (t = 3.310, 1.330, 2.388, 1.669 and 3.251, respectively, P <0.05). The 3 λHU values of venous phase in malignant SPN were higher than that of benign SPN (t = 3.803, 2.846 and 3.205, P <0.05). The difference of water related parameters (WCAP, WCVP, NWCAP, NWCVP and WCD) between malignant and benign SPN were not significant (t = 0.666, 0.257, 0.104, 0.550 and 0.585, P > 0.05). CONCLUSIONS The iodine related parameters and the slope of spectral curve are useful markers to distinguish the benign from the malignant lung diseases, and its application is extremely feasible in clinical applications.
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Affiliation(s)
- Huijuan Xiao
- The Department of Radiology, The First Affiliated Hospital of Zhengzhou University, No.1, East Jianshe Road, Zhengzhou, Henan Province, 450052, China.
| | - Yihe Liu
- The No.7 People's Hospital of Zhengzhou, 17 Jingnan 5th Road, Zhengzhou Economic and Technological Development Zone, Zhengzhou, Henan Province, 450000, China.
| | - Hongna Tan
- The Department of Radiology, The First Affiliated Hospital of Zhengzhou University, No.1, East Jianshe Road, Zhengzhou, Henan Province, 450052, China.
| | - Pan Liang
- The Department of Radiology, The First Affiliated Hospital of Zhengzhou University, No.1, East Jianshe Road, Zhengzhou, Henan Province, 450052, China.
| | - Bo Wang
- The Department of Radiology, The First Affiliated Hospital of Zhengzhou University, No.1, East Jianshe Road, Zhengzhou, Henan Province, 450052, China.
| | - Lei Su
- The Department of Radiology, The First Affiliated Hospital of Zhengzhou University, No.1, East Jianshe Road, Zhengzhou, Henan Province, 450052, China.
| | - Suya Wang
- The Department of Radiology, The First Affiliated Hospital of Zhengzhou University, No.1, East Jianshe Road, Zhengzhou, Henan Province, 450052, China.
| | - Jianbo Gao
- The Department of Radiology, The First Affiliated Hospital of Zhengzhou University, No.1, East Jianshe Road, Zhengzhou, Henan Province, 450052, China.
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Ameli-Renani S, Rahman F, Nair A, Ramsay L, Bacon JL, Weller A, Sokhi HK, Devaraj A, Madden B, Vlahos I. Dual-energy CT for imaging of pulmonary hypertension: challenges and opportunities. Radiographics 2015; 34:1769-90. [PMID: 25384277 DOI: 10.1148/rg.347130085] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Computed tomography (CT) is routinely used in the evaluation of patients with pulmonary hypertension (PH) to assess vascular anatomy and parenchymal morphology. The introduction of dual-energy CT (DECT) enables additional qualitative and quantitative insights into pulmonary hemodynamics and the extent and variability of parenchymal enhancement. Lung perfusion assessed at pulmonary blood volume imaging correlates well with findings at scintigraphy, and pulmonary blood volume defects seen in pulmonary embolism studies infer occlusive disease with increased risk of right heart dysfunction. Similarly, perfusion inhomogeneities seen in patients with PH closely reflect mosaic lung changes and may be useful for severity assessment and prognostication. The use of DECT may increase detection of peripheral thromboembolic disease, which is of particular prognostic importance in patients with chronic thromboembolic PH with microvascular involvement. Other DECT applications for imaging of PH include low-kilovoltage images with greater inherent iodine conspicuity and iodine-selective color-coded maps of vascular perfusion (both of which can improve visualization of vascular enhancement), virtual nonenhanced imaging (which better depicts vascular calcification), and, potentially, ventricular perfusion maps (to assess myocardial ischemia). In addition, quantitative assessment of central vascular and parenchymal enhancement can be used to evaluate pulmonary hemodynamics in patients with PH. The current status and potential advantages and limitations of DECT for imaging of PH are reviewed, and current evidence is supplemented with data from a tertiary referral center for PH.
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Affiliation(s)
- Seyed Ameli-Renani
- From the Department of Radiology (S.A.R., F.R., A.N., L.R., A.W., H.K.S., A.D., I.V.) and Pulmonary Hypertension Unit (J.L.B., B.M.), St George's Hospital, Blackshaw Road, London SW17 0PZ, England
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Perfusion- and pattern-based quantitative CT indexes using contrast-enhanced dual-energy computed tomography in diffuse interstitial lung disease: relationships with physiologic impairment and prediction of prognosis. Eur Radiol 2015; 26:1368-77. [DOI: 10.1007/s00330-015-3946-2] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2015] [Revised: 07/16/2015] [Accepted: 07/23/2015] [Indexed: 10/23/2022]
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Dong Y, Zheng S, Machida H, Wang B, Liu A, Liu Y, Zhang X. Differential diagnosis of osteoblastic metastases from bone islands in patients with lung cancer by single-source dual-energy CT: Advantages of spectral CT imaging. Eur J Radiol 2015; 84:901-7. [DOI: 10.1016/j.ejrad.2015.01.007] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2014] [Revised: 12/23/2014] [Accepted: 01/05/2015] [Indexed: 10/24/2022]
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Abstract
Chronic obstructive pulmonary disorder (COPD) is a systemic disease that affects the cardiovascular system through multiple pathways. Pulmonary hypertension, ventricular dysfunction, and atherosclerosis are associated with smoking and COPD, causing significant morbidity and poor prognosis. Coupling between the pulmonary and cardiovascular system involves mechanical interdependence and inflammatory pathways that potentially affect the entire circulation. Although treatments specific for COPD-related cardiovascular and pulmonary vascular disease are limited, early diagnosis, study of pathophysiology, and monitoring the effects of treatment are enhanced with improved imaging techniques. In this article, we review recent advancements in the imaging of the vasculature and the heart in patients with COPD. We also explore the potential mechanism of coupling between the progression of COPD and vascular disease. Imaging methods reviewed include specific implementations of computed tomography, magnetic resonance imaging, dual-energy computed tomography, positron emission tomography, and echocardiography. Specific applications to the proximal and distal pulmonary vasculature, as well as to the heart and systemic circulation, are also discussed.
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Abstract
OBJECTIVE Recent technologic advances in MDCT have led to the introduction of dual-energy CT (DECT). The basic principle of DECT is to acquire images at two different energy levels simultaneously and to use the attenuation differences at these different energy levels for deriving additional information, such as virtual monochromatic images, artifact suppression, and material composition of various tissues. CONCLUSION A variety of image reconstruction and postprocessing techniques are available for better demonstration and characterization of pathologic abnormalities. DECT can provide both anatomic and functional information of different organ systems. This article focuses on the main applications of DECT in emergency radiology.
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Aran S, Shaqdan KW, Abujudeh HH. Dual-energy computed tomography (DECT) in emergency radiology: basic principles, techniques, and limitations. Emerg Radiol 2014; 21:391-405. [DOI: 10.1007/s10140-014-1208-2] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2014] [Accepted: 02/17/2014] [Indexed: 02/05/2023]
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Zhu Z, Li W, Zhang L, Hu J, Wang W, Ma Z. The predictive role of dual source CT for esophageal foreign bodies. Am J Otolaryngol 2014; 35:215-8. [PMID: 24290578 DOI: 10.1016/j.amjoto.2013.10.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2013] [Accepted: 10/26/2013] [Indexed: 01/02/2023]
Abstract
INTRODUCTION Esophageal foreign bodies can be a danger to a patient's life. Flexible or rigid endoscopy is a commonly used type of invasive investigation for these, and radiological examinations are also useful. STUDY DESIGN Series of reports. METHODS AND RESULTS Multi-slice spiral CT (MSCT) can confirm and locate most foreign bodies. Dual source CT (DSCT) is a more advanced technique with double speed, 20% of the radiation dosage and higher resolution, so it is more suitable for possible esophageal foreign bodies, especially in children, with no need for sedation. We provide a preliminary experiment of a DSCT scan of two fish, and we present a series of 11 cases with DSCT scans of which 5 were positive. CONCLUSIONS Timely diagnosis and accurate localization are paramount for endoscopy. DSCT is very useful for diagnosis and evaluation of esophageal foreign bodies.
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Affiliation(s)
- Zhenghua Zhu
- Department of Otolaryngology, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, 200120, China.
| | - Wei Li
- Department of Gastroenterology and Endoscopy Room, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, 200120 China.
| | - Lei Zhang
- Department of Radiology, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, 200120 China.
| | - Jiongjiong Hu
- Department of Otolaryngology, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, 200120, China.
| | - Weihua Wang
- Department of Otolaryngology, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, 200120, China.
| | - Zhaoxin Ma
- Department of Otolaryngology, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, 200120, China.
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Xenon-Enhanced Dual-Energy CT Lung Ventilation Imaging: Techniques and Clinical Applications. AJR Am J Roentgenol 2014; 202:309-17. [PMID: 24450670 DOI: 10.2214/ajr.13.11191] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Dual-energy CT perfusion and angiography in chronic thromboembolic pulmonary hypertension: diagnostic accuracy and concordance with radionuclide scintigraphy. Eur Radiol 2013; 24:42-51. [DOI: 10.1007/s00330-013-2975-y] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2013] [Revised: 06/24/2013] [Accepted: 06/27/2013] [Indexed: 01/18/2023]
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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: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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Different perfusion pattern between acute and chronic pulmonary thromboembolism: evaluation with two-phase dual-energy perfusion CT. AJR Am J Roentgenol 2013; 200:812-7. [PMID: 23521453 DOI: 10.2214/ajr.12.8697] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
OBJECTIVE The purpose of this study was to evaluate whether two-phase dual-energy CT can differentiate between lung perfusion patterns of patients with chronic pulmonary thromboembolism (PTE) and those of patients with acute PTE. SUBJECTS AND METHODS A total of 114 patients clinically suspected to have PTE were prospectively enrolled. All patients underwent dual-energy CT at pulmonary artery (PA) and delayed phases. Of 68 patients diagnosed with PTE on CT, 42 were finally included. Iodine-related attenuation values (IRAs) were measured in PA and delayed phases for each lung segment, and IRA change ratios were calculated using the formula 100% × [(IRA of delayed phase) - (IRA of PA phase)]/(IRA of PA phase). RESULTS Among the 42 patients (19 men and 23 women; mean age, 60.3 ± 13.2 years; range, 28-82 years), 24 had a diagnosis of acute PTE and 18 of chronic PTE. Those segments with both perfusion and filling defects (n = 143) in patients with acute PTE showed no significant changes of mean IRA between PA and delayed phases, whereas the segments from patients with chronic PTE (n = 94) showed significantly increased IRA on delayed phase as compared with PA phase. The mean IRA change ratios in acute and chronic PTE were -3.14% and 191.9%, respectively (p < 0.0001). CONCLUSION Chronic PTE segments were significantly more enhanced on the delayed phase of two-phase dual-energy CT images than were acute PTE segments, possibly resulting from more extensive systemic collateral formation in chronic PTE. Two-phase dual-energy CT can be used to differentiate distinct regional perfusion patterns between acute and chronic PTE.
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Walker C, Gupta S, Raj V, Siddiqui S, Brightling CE. Imaging advances in asthma. ACTA ACUST UNITED AC 2013; 5:453-65. [PMID: 23484630 DOI: 10.1517/17530059.2011.609886] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
INTRODUCTION Asthma is a global burden, affecting 5% of the general adult population, with approximately 5 - 10% suffering from severe asthma. Severe asthma is a complex heterogeneous disease entity, with high morbidity and mortality. Recent years have seen the introduction of a vast array of new imaging technologies, which have provided the ability to comprehensively, non-invasively and functionally assess the lungs. These advances have resulted in a better understanding of the pathophysiology in severe asthma and have the unprecedented potential to unravel the structure-function relationship of severe asthma in the future. AREAS COVERED This review article chronologically describes the technological advances currently used and to be used in the future. The article covers pitfalls in imaging of the airways and lung parenchyma in asthma from chest x-rays, CT scans, MRI, confocal florescence endomicroscopy to computational fluid dynamics. EXPERT OPINION Novel qualitative and quantitative imaging techniques have enabled us to study the large airway architecture in detail, assess the small airway structure and perform functional or novel physiological evaluations. Despite spectacular advances in imaging techniques and the birth of new modalities, there is an urgent need for both proof-of-concept studies, large cross-sectional and longitudinal clinical trials in severe asthma to validate and clinically correlate imaging-derived measures. This will extend our current understanding of the pathophysiology of severe asthma, and unravel the structure-function relationship, with the potential to discover novel severe asthma phenotypes, predict mortality, morbidity and response to existing and novel pharmacological and non-pharmacological therapies.
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Affiliation(s)
- Carolina Walker
- University of Leicester , Institute for Lung Health, Department of Infection , Inflammation and Immunity, Leicester , UK
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Meinel FG, Graef A, Thieme SF, Bamberg F, Schwarz F, Sommer WH, Helck AD, Neurohr C, Reiser MF, Johnson TR. Assessing Pulmonary Perfusion in Emphysema. Invest Radiol 2013; 48:79-85. [DOI: 10.1097/rli.0b013e3182778f07] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Endoleak Detection After Endovascular Repair of Thoracic Aortic Aneurysm Using Dual-Source Dual-Energy CT: Suitable Scanning Protocols and Potential Radiation Dose Reduction. AJR Am J Roentgenol 2013; 200:451-60. [DOI: 10.2214/ajr.11.8033] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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Fuld MK, Halaweish AF, Haynes SE, Divekar AA, Guo J, Hoffman EA. Pulmonary perfused blood volume with dual-energy CT as surrogate for pulmonary perfusion assessed with dynamic multidetector CT. Radiology 2012. [PMID: 23192773 DOI: 10.1148/radiol.12112789] [Citation(s) in RCA: 94] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
PURPOSE To compare measurements of regional pulmonary perfused blood volume (PBV) and pulmonary blood flow (PBF) obtained with computed tomography (CT) in two pig models. MATERIALS AND METHODS The institutional animal care and use committee approved all animal studies. CT-derived PBF and PBV were determined in four anesthetized, mechanically ventilated, supine swine by using two methods for creating pulmonary parenchymal perfusion heterogeneity. Two animals were examined after sequentially moving a pulmonary arterial balloon catheter from a distal to a central location, and two others were examined over a range of static airway pressures, which varied the extents of regional PBF. Lung sections were divided into blocks and Pearson correlation coefficients calculated to compare matching regions between the two methods. RESULTS CT-derived PBF, CT-derived PBV, and their associated coefficients of variation (CV) were closely correlated on a region-by-region basis in both the balloon occlusion (Pearson R = 0.91 and 0.73 for animals 1 and 2, respectively; Pearson R = 0.98 and 0.87 for comparison of normalized mean and CV for animals 1 and 2, respectively) and lung inflation studies (Pearson R = 0.94 and 0.74 for animals 3 and 4, respectively; Pearson R = 0.94 and 0.69 for normalized mean and CV for animals 3 and 4, respectively). When accounting for region-based effects, correlations remained highly significant at the P < .001 level. CONCLUSION CT-derived PBV heterogeneity is a suitable surrogate for CT-derived PBF heterogeneity.
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Affiliation(s)
- Matthew K Fuld
- Department of Radiology, University of Iowa Carver College of Medicine, 200 Hawkins Dr, CC 701 GH, Iowa City, IA 52241, USA
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Komissarova M, Chong S, Frey K, Sundaram B. Imaging of acute pulmonary embolism. Emerg Radiol 2012; 20:89-101. [PMID: 23151968 DOI: 10.1007/s10140-012-1080-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2012] [Accepted: 10/01/2012] [Indexed: 12/26/2022]
Abstract
Acute pulmonary thromboembolism (PE) is a cardiovascular emergency associated with significant morbidity and a 5-35 % mortality for untreated pulmonary embolism. If promptly diagnosed and treated, the mortality rate can be significantly reduced. Diagnosis of acute PE continues to be a clinical challenge, with diagnostic imaging playing an important role. This review discusses the clinical challenges of diagnosing acute PE, presents an evidence-based review of the current tests and ever-evolving imaging technology, and highlights special considerations related to radiation dose, contrast media use, and pregnant patients.
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Affiliation(s)
- Maria Komissarova
- Divisions of Emergency, Cardiothoracic and Nuclear Radiology, Department of Radiology, University of Michigan, 1500 E. Medical Center Drive, TC B1-140D, Ann Arbor, MI 48109, USA
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[Dual energy CT for thoracic applications]. Rev Mal Respir 2012; 29:1268-71. [PMID: 23228684 DOI: 10.1016/j.rmr.2012.08.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2012] [Accepted: 06/10/2012] [Indexed: 11/23/2022]
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Okada M, Kunihiro Y, Nakashima Y, Matsunaga N, Sano Y, Yuasa Y, Narazaki A, Kudomi S, Koike M, Kido S. The low attenuation area on dual-energy perfusion CT: Correlation with the pulmonary function tests and quantitative CT measurements. Eur J Radiol 2012; 81:2892-9. [DOI: 10.1016/j.ejrad.2011.11.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2011] [Revised: 11/01/2011] [Accepted: 11/02/2011] [Indexed: 10/14/2022]
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Badea CT, Guo X, Clark D, Johnston SM, Marshall C, Piantadosi C. Lung imaging in rodents using dual energy micro-CT. PROCEEDINGS OF SPIE--THE INTERNATIONAL SOCIETY FOR OPTICAL ENGINEERING 2012; 8317. [PMID: 24027623 DOI: 10.1117/12.912155] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Dual energy CT imaging is expected to play a major role in the diagnostic arena as it provides material decomposition on an elemental basis. The purpose of this work is to investigate the use of dual energy micro-CT for the estimation of vascular, tissue, and air fractions in rodent lungs using a post-reconstruction three-material decomposition method. We have tested our method using both simulations and experimental work. Using simulations, we have estimated the accuracy limits of the decomposition for realistic micro-CT noise levels. Next, we performed experiments involving ex vivo lung imaging in which intact lungs were carefully removed from the thorax, were injected with an iodine-based contrast agent and inflated with air at different volume levels. Finally, we performed in vivo imaging studies in (n=5) C57BL/6 mice using fast prospective respiratory gating in end-inspiration and end-expiration for three different levels of positive end-expiratory pressure (PEEP). Prior to imaging, mice were injected with a liposomal blood pool contrast agent. The mean accuracy values were for Air (95.5%), Blood (96%), and Tissue (92.4%). The absolute accuracy in determining all fraction materials was 94.6%. The minimum difference that we could detect in material fractions was 15%. As expected, an increase in PEEP levels for the living mouse resulted in statistically significant increases in air fractions at end-expiration, but no significant changes in end-inspiration. Our method has applicability in preclinical pulmonary studies where various physiological changes can occur as a result of genetic changes, lung disease, or drug effects.
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Affiliation(s)
- C T Badea
- Center for In Vivo Microscopy, Department of Radiology, Tsinghua University, Beijing, China
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Badea CT, Guo X, Clark D, Johnston SM, Marshall CD, Piantadosi CA. Dual-energy micro-CT of the rodent lung. Am J Physiol Lung Cell Mol Physiol 2012; 302:L1088-97. [PMID: 22427526 DOI: 10.1152/ajplung.00359.2011] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The purpose of this work is to investigate the use of dual-energy micro-computed tomography (CT) for the estimation of vascular, tissue, and air fractions in rodent lungs using a postreconstruction three material decomposition method. Using simulations, we have estimated the accuracy limits of the decomposition for realistic micro-CT noise levels. Next, we performed experiments involving ex vivo lung imaging in which intact rat lungs were carefully removed from the thorax, injected with an iodine-based contrast agent, and then inflated with different volumes of air (n = 2). Finally, we performed in vivo imaging studies in C57BL/6 mice (n = 5) using fast prospective respiratory gating in end inspiration and end expiration for three different levels of positive end expiratory pressure (PEEP). Before imaging, mice were injected with a liposomal blood pool contrast agent. The three-dimensional air, tissue, and blood fraction maps were computed and analyzed. The results indicate that separation and volume estimation of the three material components of the lungs are possible. The mean accuracy values for air, blood, and tissue were 93, 93, and 90%, respectively. The absolute accuracy in determining all fraction materials was 91.6%. The coefficient of variation was small (2.5%) indicating good repeatability. The minimum difference that we could detect in material fractions was 15%. As expected, an increase in PEEP levels for the living mouse resulted in statistically significant increases in air fractions at end expiration but no significant changes at end inspiration. Our method has applicability in preclinical pulmonary studies where changes in lung structure and gas volume as a result of lung injury, environmental exposures, or drug bioactivity would have important physiological implications.
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Affiliation(s)
- C T Badea
- Center for In Vivo Microscopy, Department of Radiology, Duke University Medical Center, Durham, NC 27710, USA.
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Pulmonary blood volume imaging with dual-energy computed tomography: Spectrum of findings. Clin Radiol 2012; 67:69-77. [DOI: 10.1016/j.crad.2010.12.021] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2010] [Revised: 12/10/2010] [Accepted: 12/14/2010] [Indexed: 11/22/2022]
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Rossi A, Attinà D, Borgonovi A, Buia F, De Luca F, Guidalotti P, Fughelli P, Galiè N, Zompatori M. Evaluation of mosaic pattern areas in HRCT with Min-IP reconstructions in patients with pulmonary hypertension: Could this evaluation replace lung perfusion scintigraphy? Eur J Radiol 2012; 81:e1-6. [DOI: 10.1016/j.ejrad.2010.09.032] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2010] [Accepted: 09/27/2010] [Indexed: 11/28/2022]
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Walker C, Gupta S, Hartley R, Brightling CE. Computed tomography scans in severe asthma: utility and clinical implications. Curr Opin Pulm Med 2012; 18:42-7. [PMID: 22112997 PMCID: PMC3387553 DOI: 10.1097/mcp.0b013e32834db255] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
PURPOSE OF REVIEW Asthma is a global burden, affecting 5% of the general adult population, of whom approximately 5-10% suffer from severe asthma. Severe asthma is a complex heterogeneous disease entity, with high morbidity and mortality. Increasingly novel techniques in computed tomography (CT) are being used to understand the pathophysiology of severe asthma. The utility and clinical implications of these CT techniques are the focus of this review. RECENT FINDINGS Novel qualitative and quantitative CT imaging techniques have enabled us to study the large airway architecture in detail, assess the small airway structure, and perform functional analysis of regional ventilation. SUMMARY Despite advances in CT imaging techniques, there is an urgent need for both proof-of-concept studies and large cross-sectional and longitudinal clinical trials in severe asthma to validate and clinically correlate imaging derived measures. This will extend our current understanding of the pathophysiology of severe asthma, and unravel the structure-function relationship, with the potential to discover novel severe asthma phenotypes and predict mortality, morbidity, and response to existing and novel pharmacological and nonpharmacological therapies.
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Affiliation(s)
- Carolina Walker
- Department of Infection, Institute for Lung Health, Immunity & Inflammation, University of Leicester, Leicester, UK
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CT Imaging of Pulmonary Embolism: Current Status. CURRENT CARDIOVASCULAR IMAGING REPORTS 2011. [DOI: 10.1007/s12410-011-9112-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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Chai X, Zhang LJ, Yeh BM, Zhao YE, Hu XB, Lu GM. Acute and subacute dual energy CT findings of pulmonary embolism in rabbits: correlation with histopathology. Br J Radiol 2011; 85:613-22. [PMID: 21791503 DOI: 10.1259/bjr/67661352] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
OBJECTIVE The purpose of this study was to describe quantitative dual energy CT (DECT) findings and their accuracy in the detection of acute and subacute pulmonary embolism (PE) in rabbits. METHODS Pulmonary emboli were created in 24 rabbits by gelatin sponge femoral vein injection. Conventional CT pulmonary angiography (CTPA) and DECT were obtained at either 2 h, 1 day, 3 days or 7 days after embolisation (n=6 rabbits for each time point). The location and number of PEs in the different stages were recorded at CTPA and iodine maps from DECT on a per-lobe basis. With histopathology as the reference standard, sensitivity and specificity of CTPA and DECT were calculated. CT and iodine map overlay values of the embolic and non-embolic areas were measured for each scan. RESULTS With histopathology as the reference standard, the overall sensitivity and specificity of CTPA were 98% and 100% and those of iodine maps were 100% and 95%, respectively. Conventional CT and iodine map values of the embolised and non-embolised areas were significantly different between 2 h and 1 day (p<0.001), but not between 3 days and 7 days (p>0.05). A statistical difference was found for overlay values measured in the embolic and non-embolic regions for four groups. CONCLUSION Iodine maps derived from DECT show alterations in lung perfusion for acute and subacute PE in an experimental rabbit model and show comparable sensitivity for PE detection and conventional CTPA.
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Affiliation(s)
- X Chai
- Department of Medical Imaging, Jinling Hospital, Clinical School of Medical College, Nanjing University, Jiangsu, China
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Effect of Organ Enhancement and Habitus on Estimation of Unenhanced Attenuation at Contrast-Enhanced Dual-Energy MDCT: Concepts for Individualized and Organ-Specific Spectral Iodine Subtraction Strategies. AJR Am J Roentgenol 2011; 196:W558-64. [DOI: 10.2214/ajr.10.4858] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Abstract
OBJECTIVE The purpose of this article is to discuss the diagnostic role of pulmonary CT angiography (CTA) in the workup of pulmonary embolism (PE), including specific populations, and issues such as pulmonary CTA combined with indirect CT venography; radiation dose considerations; the management of isolated subsegmental PE; and new technologic developments, such as dual-source/dual-energy pulmonary CTA. CONCLUSION The role of pulmonary CTA will continue to grow with the emergence of MDCT and dual-energy CT and their improved capabilities. However, the need for any given CT examination should always be justified on the basis of the individual patient's benefits and risks.
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Dual-energy CT angiography for assessment of regional pulmonary perfusion in patients with chronic thromboembolic pulmonary hypertension: initial experience. AJR Am J Roentgenol 2011; 196:524-32. [PMID: 21343493 DOI: 10.2214/ajr.10.4842] [Citation(s) in RCA: 107] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
OBJECTIVE This study assessed the utility of dual-energy pulmonary CT angiography (CTA) for noninvasive assessment of regional pulmonary perfusion in patients with chronic thromboembolic pulmonary hypertension (CTEPH). Regional perfusion abnormalities were correlated with hemodynamic parameters and structural abnormalities on pulmonary CTA. SUBJECTS AND METHODS Twenty patients with CTEPH (11 men and nine women; mean age, 61.5 years) underwent pulmonary CTA with a dual-energy technique. Right heart catheterization data were available in 15 cases. Scan parameters were as follows: tube A, 140 kV (75 mA); tube B, 80 kV (300 mA); gantry rotation, 500 milliseconds; pitch, 0.5; and collimation, 14 × 1.2 mm. An iodine map was generated via three-material-decomposition and was scored for extent of hypoperfusion. Correlation was made with mosaic attenuation pattern, extent of vascular obstruction, and right heart hemodynamics. Iodine attenuation values were analyzed within completely occluded, partially occluded, and disease-free lobes. RESULTS A strong correlation existed between dual-energy CT-derived perfusion and mosaic attenuation pattern when both lobar (r > 0.6; n = 20; p < 0.006) and whole-lung scores were assessed (r = 0.77; n = 20; p < 0.001). There was no statistically significant correlation between dual-energy CT perfusion and vascular obstructive index, mean pulmonary artery pressure, or pulmonary vascular resistance (p > 0.08). Of 42 completely occluded lobes, 27 (64%) had demonstrable residual perfusion (mismatching), suggesting that blood supply was maintained via systemic collaterals. CONCLUSION Dual-energy CT can offer a "one-stop" assessment of anatomy and perfusion in CTEPH. The additional information provided by dual-energy CT could have a future role in helping guide patient selection for thromboendarterectomy surgery.
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Detection of pulmonary embolism comparison between dual energy CT and MR angiography in a rabbit model. Acad Radiol 2010; 17:1550-9. [PMID: 21056850 DOI: 10.1016/j.acra.2010.09.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2010] [Revised: 08/15/2010] [Accepted: 09/22/2010] [Indexed: 11/21/2022]
Abstract
RATIONALE AND OBJECTIVES The purpose of this study was to compare the efficacy of dual-energy computed tomography (DECT), time-resolved magnetic resonance (MR) imaging (MRI) perfusion measurements, and high-resolution MR angiography (MRA) for the detection of pulmonary embolism (PE) in a rabbit model. MATERIALS AND METHODS Two hours after Gelfoam (n = 16) or saline (n = 2) injection into the femoral vein, 18 rabbits were first imaged using dual-energy computed tomographic pulmonary angiography (CTPA), from which blood flow imaging (BFI) were produced. Next, the rabbits underwent time-resolved MR perfusion measurements and MRA using a 3.0-T scanner. Two radiologists who were blinded to histopathologic findings independently evaluated the results of CTPA, BFI, time-resolved MR perfusion, and MRA for each rabbit and recorded the locations and number of pulmonary clots on a per lobe basis. Immediately after MRI examination, pathologic determination of the locations and numbers of lung lobes with PE was recorded. Histopathologic results served as the reference standard to determine the sensitivity and specificity of DECT (BFI and CTPA) and MRI (time-resolved MR perfusion and high-resolution MRA) for the detection of PE. RESULTS The induction of PE was successful in all animals, but three rabbits were excluded because of death prior to MRI procedures (caused by complications during the embolization procedure); only data from the remaining 15 rabbits were included in the final analysis. Histopathology demonstrated 24 lobes with clots and 51 lobes without clots. CTPA, BFI, and MRI correctly identified PE in 23, 23, and 20 lobes, respectively, and the absence of emboli in 48, 46, and 46 lobes, respectively; these results corresponded to sensitivities of 95.8%, 95.8%, and 83.3% and specificities of 94.1%, 90.2%, and 90.2% for reader 1 and sensitivities of 91.7%, 91.7%, and 87.5% and specificities of 90.2%, 88.2%, and 88.2% for reader 2 for CTPA, BFI, and MRI, respectively. Good or excellent intermodality and interreader agreement among CTPA, BFI, and MRI were found. CONCLUSIONS DECT can simultaneously provide high-resolution pulmonary artery and lung iodine mapping with slightly high diagnostic accuracy for the detection of PE compared to MRI in an experimental rabbit model of PE. This improvement was not statistically significant given the study sample size.
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Feasibility of gadolinium-enhanced dual energy CT pulmonary angiography: a pilot study in rabbits. Int J Cardiovasc Imaging 2010; 27:1069-80. [DOI: 10.1007/s10554-010-9755-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/29/2010] [Accepted: 11/12/2010] [Indexed: 10/18/2022]
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Zhang LJ, Wang ZJ, Lu L, Zhu K, Chai X, Zhao YE, Peng J, Lu GM. Dual energy CT ventilation imaging after aerosol inhalation of iodinated contrast medium in rabbits. Eur J Radiol 2010; 78:266-71. [PMID: 21109377 DOI: 10.1016/j.ejrad.2010.10.029] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2010] [Revised: 10/11/2010] [Accepted: 10/20/2010] [Indexed: 11/30/2022]
Abstract
PURPOSE To assess the feasibility of dual energy CT (DECT) after aerosol inhalation of iodinated contrast medium for the evaluation of ventilation function in rabbits with airway obstruction. MATERIALS AND METHODS The study was approved by our institutional animal experimental committee and performed according to animal care guidelines. Airway obstruction was created by injecting gelatin sponge into the right bronchus of 6 New Zealand rabbits. One additional rabbit served as control without airway obstruction. All 7 rabbits then underwent inhalation of aerosol iodinated contrast medium for 5 min, followed by DECT of the lungs from which ventilation CT images were created. CT number and overlay value (calculated iodine enhancement on the ventilation images in hounsfield unit) of the obstructed and non-obstructed lung lobes were measured at 80-kVp, 140-kVp, and weighted average 120-kVp. Immediately after DECT scan, the rabbits were sacrificed, the lungs were removed and detailed pathological examination of the locations and parenchymal changes of the obstructed lung lobes were performed and correlated with DECT ventilation imaging findings. RESULTS Data from one rabbit with airway obstruction were excluded because of post-procedure pneumatothorax. Seventeen normal lung lobes without airway obstruction proven by histopathology had nearly homogeneous ventilation, while 13 abnormal lung lobes had ventilation defects on DECT ventilation images. CT numbers and overlay values of the normal (CT number, -737.77 ± 71.46 HU, -768.84 ± 73.86 HU, -731.86 ± 65.92 HU for 140-kVp, 80-kVp, and weighted average 120-kVp; overlay value, 46.58 ± 19.49 HU) and abnormal lung lobes (CT number, -183.58 ± 173.37 HU, -124.93 ± 242.23 HU, -166.07 ± 191.57 HU for 140-kVp, 80-kVp, and weighted average 120-kVp; overlay value, 0.00 ± 0.00 HU) were significantly different at 80-kVp, 140-kVp, and weighted average 120-kVp (P < 0.001 for all). Diffuse hemorrhage, inflammatory cell infiltration, and exudation were observed at histopathology in the obstructed lung lobes. CONCLUSIONS It is feasible to study regional lung ventilation function using DECT after aerosol inhalation of iodinated contrast medium in rabbit. The safety of inhalation of iodine contrast medium is unknown, and has to be investigated further before use of this new method in humans.
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Affiliation(s)
- Long-Jiang Zhang
- Department of Medical Imaging, Jinling Hospital, Clinical School of Medical College, Nanjing University, 305 Zhongshan East Road, Xuanwu District, Nanjing, Jiangsu 210002, China
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Focal Iodine Defects on Color-Coded Iodine Perfusion Maps of Dual-Energy Pulmonary CT Angiography Images: A Potential Diagnostic Pitfall. AJR Am J Roentgenol 2010; 195:W325-30. [DOI: 10.2214/ajr.09.3241] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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