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Hoche C, Henderson A, Ifergan H, Gaudron M, Magni C, Maldonado I, Cottier JP, Pasi M, Boulouis G, Cohen C. Determinants and Clinical Relevance of Iodine Contrast Extravasation after Endovascular Thrombectomy: A Dual-Energy CT Study. AJNR Am J Neuroradiol 2023; 45:30-36. [PMID: 38323978 PMCID: PMC10756568 DOI: 10.3174/ajnr.a8081] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Accepted: 10/29/2023] [Indexed: 02/08/2024]
Abstract
BACKGROUND AND PURPOSE Iodine contrast extravasation (ICE) is common in patients with acute ischemic stroke (AIS) after endovascular-thrombectomy (EVT). The aim of our study was to evaluate the incidence of ICE assessed by dual-energy CT (DECT), its determinants, and associations with clinical outcome. MATERIALS AND METHODS We retrospectively examined imaging parameters and clinical factors from consecutive patients with AIS treated with EVT who had a DECT 24 hours thereafter, identified at a single academic center. Associations between ICE, clinical, imaging, and procedural parameters, as well as clinical outcome were explored by using univariable and multivariable models. RESULTS A total of 197 consecutive patients were included (period 2019-2020), of which 53 (27%) demonstrated ICE that was pure ICE in 30/53 (57%) and mixed with intracranial hemorrhage (ICH) in 23/53 (43%). Low initial-ASPECTS, high per-procedural-contrast volume injected, and high admission-glycemia were independently associated with ICE (respectively, OR = 0.43, 95% CI, 0.16-1.13, P = .047; OR = 1.02, 95% CI, 1.00-1.04, P = .003; OR = 8.92, 95% CI, 0.63-125.77, P = .043). ICE was independently associated with ICH (P = .047), but not with poorer clinical outcome (6-month mRS >2, P = .223). Univariate analysis demonstrated that low ADC, higher ischemic volume, ICA occlusion, mass effect, longer procedure duration, combined thrombectomy technique, higher number of device passes, and lower recanalization rate were associated with ICE (respectively, P = .002; <.001; .002; <.001; .002; 0.011; <0.001; 0.015). CONCLUSIONS ICE evaluated with DECT is a relatively frequent finding after EVT, present in almost one-third of patients. Lower admission ASPECTS, higher glycemia, and high contrast volume injected per procedure were associated with ICE. We also found an association between ICE and ICH, confirming blood-brain barrier alteration as a major determinant of ICH.
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Affiliation(s)
- Clémence Hoche
- Neurology (C.H., M.G., M.P.), University Hospital of Tours, Tours, France
| | - Alba Henderson
- Department of Diagnostic Neuroradiology (A.H., C.M., C.C.), University Regional Hospital of Orleans, Orléans, France
| | - Héloïse Ifergan
- From the Departments of Diagnostic and Interventional Neuroradiology (H.I., J.-P.C.,G.B.), University Hospital of Tours, Tours, France
| | - Marie Gaudron
- Neurology (C.H., M.G., M.P.), University Hospital of Tours, Tours, France
| | - Christophe Magni
- Department of Diagnostic Neuroradiology (A.H., C.M., C.C.), University Regional Hospital of Orleans, Orléans, France
| | | | - Jean-Philippe Cottier
- From the Departments of Diagnostic and Interventional Neuroradiology (H.I., J.-P.C.,G.B.), University Hospital of Tours, Tours, France
| | - Marco Pasi
- Neurology (C.H., M.G., M.P.), University Hospital of Tours, Tours, France
| | - Grégoire Boulouis
- From the Departments of Diagnostic and Interventional Neuroradiology (H.I., J.-P.C.,G.B.), University Hospital of Tours, Tours, France
| | - Clara Cohen
- Department of Diagnostic Neuroradiology (A.H., C.M., C.C.), University Regional Hospital of Orleans, Orléans, France
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Zhao X, Wang X, Wang S, Chen L, Sun S. Absolute and relative iodine concentrations in the spot sign and haematoma for prediction of haematoma expansion in spontaneous intracerebral haemorrhage. Clin Radiol 2023; 78:e950-e957. [PMID: 37690974 DOI: 10.1016/j.crad.2023.08.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Revised: 08/15/2023] [Accepted: 08/16/2023] [Indexed: 09/12/2023]
Abstract
AIM To explore the predictive value of absolute and relative iodine concentrations in the spot sign (SS) and haematoma on gemstone spectral imaging (GSI) for haematoma expansion (HE). MATERIALS AND METHODS Patients with spontaneous intracerebral haemorrhage (ICH) who underwent computed tomography (CT) angiography using GSI were divided into an SS-positive group and an SS-negative group. In the SS-positive group, absolute and relative iodine concentrations in the SS (aICIS and rICIS, respectively) were measured. In the SS-negative group, absolute and relative iodine concentrations in haematoma (aICIH and rICIH, respectively) were measured. The area under the receiver operating characteristic curve (AUC-ROC) was used to investigate the HE predictive performance of aICIS, rICIS, and their combination in the SS-positive group, as well as the HE predictive performance of aICIH, rICIH, and their combination in the SS-negative group. The risk variables for HE in the two groups were investigated separately using logistic regression. RESULTS A total of 123 spontaneous ICH patients were enrolled. In the SS-positive group, the AUC of aICIS, rICIS, and their combination for predicting HE were 0.853, 0.893, and 0.922, respectively. rICIS was demonstrated to be a standalone predictor of HE via logistic regression. In the SS-negative group, aICIH, rICIH, and their combination had AUC-ROC values of 0.552, 0.783, and 0.851, respectively, to predict HE. According to multivariate analysis, rICIH was a reliable predictor of HE. CONCLUSION Absolute and relative iodine concentrations in the SS and haematoma can predict HE.
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Affiliation(s)
- X Zhao
- Department of Radiology, Beijing Tiantan Hospital, Capital Medical University, No. 119 Nansihuan Road, Fengtai District, Beijing 100070, China
| | - X Wang
- Department of Radiology, Beijing Tiantan Hospital, Capital Medical University, No. 119 Nansihuan Road, Fengtai District, Beijing 100070, China
| | - S Wang
- Department of Radiology, Beijing Tiantan Hospital, Capital Medical University, No. 119 Nansihuan Road, Fengtai District, Beijing 100070, China
| | - L Chen
- Department of Radiology, Beijing Tiantan Hospital, Capital Medical University, No. 119 Nansihuan Road, Fengtai District, Beijing 100070, China
| | - S Sun
- Department of Radiology, Beijing Tiantan Hospital, Capital Medical University, No. 119 Nansihuan Road, Fengtai District, Beijing 100070, China; Department of Radiology, Beijing Neurosurgical Institute, No. 119 Nansihuan Road, Fengtai District, Beijing 100070, China.
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Schmidt TG, Sidky EY, Pan X, Barber RF, Grönberg F, Sjölin M, Danielsson M. Constrained one-step material decomposition reconstruction of head CT data from a silicon photon-counting prototype. Med Phys 2023; 50:6008-6021. [PMID: 37523258 PMCID: PMC11073613 DOI: 10.1002/mp.16649] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Revised: 06/23/2023] [Accepted: 07/15/2023] [Indexed: 08/02/2023] Open
Abstract
BACKGROUND Spectral CT material decomposition provides quantitative information but is challenged by the instability of the inversion into basis materials. We have previously proposed the constrained One-Step Spectral CT Image Reconstruction (cOSSCIR) algorithm to stabilize the material decomposition inversion by directly estimating basis material images from spectral CT data. cOSSCIR was previously investigated on phantom data. PURPOSE This study investigates the performance of cOSSCIR using head CT datasets acquired on a clinical photon-counting CT (PCCT) prototype. This is the first investigation of cOSSCIR for large-scale, anatomically complex, clinical PCCT data. The cOSSCIR decomposition is preceded by a spectrum estimation and nonlinear counts correction calibration step to address nonideal detector effects. METHODS Head CT data were acquired on an early prototype clinical PCCT system using an edge-on silicon detector with eight energy bins. Calibration data of a step wedge phantom were also acquired and used to train a spectral model to account for the source spectrum and detector spectral response, and also to train a nonlinear counts correction model to account for pulse pileup effects. The cOSSCIR algorithm optimized the bone and adipose basis images directly from the photon counts data, while placing a grouped total variation (TV) constraint on the basis images. For comparison, basis images were also reconstructed by a two-step projection-domain approach of Maximum Likelihood Estimation (MLE) for decomposing basis sinograms, followed by filtered backprojection (MLE + FBP) or a TV minimization algorithm (MLE + TVmin ) to reconstruct basis images. We hypothesize that the cOSSCIR approach will provide a more stable inversion into basis images compared to two-step approaches. To investigate this hypothesis, the noise standard deviation in bone and soft-tissue regions of interest (ROIs) in the reconstructed images were compared between cOSSCIR and the two-step methods for a range of regularization constraint settings. RESULTS cOSSCIR reduced the noise standard deviation in the basis images by a factor of two to six compared to that of MLE + TVmin , when both algorithms were constrained to produce images with the same TV. The cOSSCIR images demonstrated qualitatively improved spatial resolution and depiction of fine anatomical detail. The MLE + TVmin algorithm resulted in lower noise standard deviation than cOSSCIR for the virtual monoenergetic images (VMIs) at higher energy levels and constraint settings, while the cOSSCIR VMIs resulted in lower noise standard deviation at lower energy levels and overall higher qualitative spatial resolution. There were no statistically significant differences in the mean values within the bone region of images reconstructed by the studied algorithms. There were statistically significant differences in the mean values within the soft-tissue region of the reconstructed images, with cOSSCIR producing mean values closer to the expected values. CONCLUSIONS The cOSSCIR algorithm, combined with our previously proposed spectral model estimation and nonlinear counts correction method, successfully estimated bone and adipose basis images from high resolution, large-scale patient data from a clinical PCCT prototype. The cOSSCIR basis images were able to depict fine anatomical details with a factor of two to six reduction in noise standard deviation compared to that of the MLE + TVmin two-step approach.
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Affiliation(s)
- Taly Gilat Schmidt
- Department of Biomedical Engineering, Marquette University and Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Emil Y Sidky
- Department of Radiology, University of Chicago, Chicago, Illinois, USA
| | - Xiaochuan Pan
- Department of Radiology, University of Chicago, Chicago, Illinois, USA
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Ehrengut C, Denecke T, Meyer HJ. Benefits of Dual-Layer Spectral CT Imaging in Staging and Preoperative Evaluation of Pancreatic Ductal Adenocarcinoma. J Clin Med 2023; 12:6145. [PMID: 37834789 PMCID: PMC10573525 DOI: 10.3390/jcm12196145] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2023] [Revised: 09/10/2023] [Accepted: 09/20/2023] [Indexed: 10/15/2023] Open
Abstract
Imaging of pancreatic malignancies is challenging but has a major impact on the patients therapeutic approach and outcome. In particular with pancreatic ductal adenocarcinoma (PDAC), usually a hypovascularized tumor, conventional CT imaging can be prone to errors in determining tumor extent and presence of metastatic disease. Dual-layer spectral detector CT (SDCT) is an emerging technique for acquiring spectral information without the need for prospective patient selection or specific protocols, with a detector capable of differentiating high- and low-energy photons to acquire full spectral images. In this review, we present the diagnostic benefits and capabilities of modern SDCT imaging with a focus on PDAC. We highlight the most useful virtual reconstructions in oncologic imaging and their benefits in staging and assessment of resectability in PDAC, including the assessment of tumor extent, vascular infiltration, and metastatic disease. We present imaging examples on a latest-generation SDCT scanner.
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Affiliation(s)
| | | | - Hans-Jonas Meyer
- Klinik und Poliklinik für Diagnostische und Interventionelle Radiologie, Universitätsklinikum Leipzig, 04103 Leipzig, Germany; (C.E.)
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Duprez T, Vlassenbroek A, Peeters A, Poncelet PA, Levecque E, Austein F, Pahn G, Nae Y, Abdallah S, Coche E. Preliminary experience of CT imaging of the ischaemic brain penumbra through spectral processing of multiphasic CTA datasets. Sci Rep 2023; 13:11431. [PMID: 37454162 PMCID: PMC10349801 DOI: 10.1038/s41598-023-38370-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Accepted: 07/07/2023] [Indexed: 07/18/2023] Open
Abstract
To assess ischaemic penumbra through the post-processing of the spectral multiphasic CT Angiography (mCTA) data in acute ischaemic stroke (AIS) patients. Thirty one consecutive patients strongly suspected of severe Middle Cerebral Artery AIS presenting less than 6 h after onset of symptoms or with unknown time of onset of symptoms underwent a standardized CT protocol in spectral mode including Non Contrast CT, mCTA, and Perfusion CT (CTP) on a dual-layer MDCT system. Areas disclosing delayed enhancement on iodine density (ID) maps were highlighted by subtraction of the serial mCTA datasets. Two neuroradiologists independently rated the correspondence between delayed enhancing areas at mCTA and the penumbral/infarcted areas delineated by two validated CTP applications using a 5-levels scoring scale. Interobserver agreement between observers was evaluated by kappa statistics. Dose delivery was recorded for each acquisition. Averaged correspondence score between penumbra delineation using subtracted mCTA-derived ID maps and CTP ones was 2.76 for one application and 2.9 for the other with best interobserver agreement kappa value at 0.59. All 6 stroke mimics out of the 31 patients' cohort were correctly identified. Average dose delivery was 7.55 mSv for the whole procedure of which CTP accounted for 39.7%. Post-processing of spectral mCTA data could allow clinically relevant assessment of the presence or absence of ischaemic penumbra in AIS-suspected patients if results of this proof-of-concept study should be confirmed in larger patients'series.
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Affiliation(s)
- T Duprez
- Department of Radiology, Cliniques Universitaires Saint-Luc, Université Catholique de Louvain (UCLouvain), Avenue Hippocrate 10, 1200, Brussels, Belgium
| | - A Vlassenbroek
- CT/AMI Clinical Science, Philips Health Systems, Avenue du Bourgmestre Etienne Demunter 1, 1090, Brussels, Belgium.
| | - A Peeters
- Department of Neurology, Stroke Unit, Cliniques Universitaires Saint-Luc, Université Catholique de Louvain (UCLouvain), Avenue Hippocrate 10, 1200, Brussels, Belgium
| | - P A Poncelet
- Department of Medical Imaging, Grand Hôpital de Charleroi (GHdC), Grand'Rue, 3, 6000, Charleroi, Belgium
| | - E Levecque
- Department of Neurology, Stroke Unit, Cliniques Universitaires Saint-Luc, Université Catholique de Louvain (UCLouvain), Avenue Hippocrate 10, 1200, Brussels, Belgium
| | - F Austein
- Department of Diagnostic and Interventional Neuroradiology, University Medical Center Hamburg-Eppendorf, Martinistraße 52, 20426, Hamburg, Germany
| | - G Pahn
- PD CT/AMI Clinical Science, Philips GmbH Market DACH, Röntgenstraße 22-24, 22335, Hamburg, Germany
| | - Y Nae
- CT/AMI Clinical Science, Advanced Technologies Center, Philips Medical Systems Technologies Ltd., Building No. 34, P.O. Box 325, 3100202, Haifa, Israel
| | - S Abdallah
- CT/AMI Clinical Science, Advanced Technologies Center, Philips Medical Systems Technologies Ltd., Building No. 34, P.O. Box 325, 3100202, Haifa, Israel
| | - E Coche
- Department of Radiology, Cliniques Universitaires Saint-Luc, Université Catholique de Louvain (UCLouvain), Avenue Hippocrate 10, 1200, Brussels, Belgium
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Cademartiri F, Meloni A, Pistoia L, Degiorgi G, Clemente A, De Gori C, Positano V, Celi S, Berti S, Emdin M, Panetta D, Menichetti L, Punzo B, Cavaliere C, Bossone E, Saba L, Cau R, Grutta LL, Maffei E. Dual Source Photon-Counting Computed Tomography-Part II: Clinical Overview of Neurovascular Applications. J Clin Med 2023; 12:jcm12113626. [PMID: 37297821 DOI: 10.3390/jcm12113626] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2023] [Revised: 05/15/2023] [Accepted: 05/18/2023] [Indexed: 06/12/2023] Open
Abstract
Photon-counting detector (PCD) is a novel computed tomography detector technology (photon-counting computed tomography-PCCT) that presents many advantages in the neurovascular field, such as increased spatial resolution, reduced radiation exposure, and optimization of the use of contrast agents and material decomposition. In this overview of the existing literature on PCCT, we describe the physical principles, the advantages and the disadvantages of conventional energy integrating detectors and PCDs, and finally, we discuss the applications of the PCD, focusing specifically on its implementation in the neurovascular field.
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Affiliation(s)
| | - Antonella Meloni
- Department of Radiology, Fondazione Monasterio/CNR, 56124 Pisa, Italy
- Department of Bioengineering, Fondazione Monasterio/CNR, 56124 Pisa, Italy
| | - Laura Pistoia
- Department of Radiology, Fondazione Monasterio/CNR, 56124 Pisa, Italy
| | - Giulia Degiorgi
- Department of Radiology, Fondazione Monasterio/CNR, 56124 Pisa, Italy
| | - Alberto Clemente
- Department of Radiology, Fondazione Monasterio/CNR, 56124 Pisa, Italy
| | - Carmelo De Gori
- Department of Radiology, Fondazione Monasterio/CNR, 56124 Pisa, Italy
| | - Vincenzo Positano
- Department of Radiology, Fondazione Monasterio/CNR, 56124 Pisa, Italy
- Department of Bioengineering, Fondazione Monasterio/CNR, 56124 Pisa, Italy
| | - Simona Celi
- BioCardioLab, Department of Bioengineering, Fondazione Monasterio/CNR, 54100 Massa, Italy
| | - Sergio Berti
- Cardiology Unit, Ospedale del Cuore, Fondazione Monasterio/CNR, 54100 Massa, Italy
| | - Michele Emdin
- Department of Cardiology, Fondazione Monasterio/CNR, 56124 Pisa, Italy
| | - Daniele Panetta
- Institute of Clinical Physiology, National Council of Research, 56124 Pisa, Italy
| | - Luca Menichetti
- Institute of Clinical Physiology, National Council of Research, 56124 Pisa, Italy
| | - Bruna Punzo
- Department of Radiology, IRCCS SynLab-SDN, 80131 Naples, Italy
| | - Carlo Cavaliere
- Department of Radiology, IRCCS SynLab-SDN, 80131 Naples, Italy
| | - Eduardo Bossone
- Department of Cardiology, Ospedale Cardarelli, 80131 Naples, Italy
| | - Luca Saba
- Department of Radiology, University Hospital, 09042 Monserrato, Italy
| | - Riccardo Cau
- Department of Radiology, University Hospital, 09042 Monserrato, Italy
| | - Ludovico La Grutta
- Department of Health Promotion, Mother and Child Care, Internal Medicine and Medical Specialties-ProMISE, Department of Radiology, University Hospital "P. Giaccone", 90127 Palermo, Italy
| | - Erica Maffei
- Department of Radiology, Fondazione Monasterio/CNR, 56124 Pisa, Italy
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Sauerbeck J, Adam G, Meyer M. Spectral CT in Oncology. ROFO-FORTSCHR RONTG 2023; 195:21-29. [PMID: 36167316 DOI: 10.1055/a-1902-9949] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
BACKGROUND Spectral CT is gaining increasing clinical importance with multiple potential applications, including oncological imaging. Spectral CT-specific image data offers multiple advantages over conventional CT image data through various post-processing algorithms, which will be highlighted in the following review. METHODOLOGY The purpose of this review article is to provide an overview of potential useful oncologic applications of spectral CT and to highlight specific spectral CT pitfalls. The technical background, clinical advantages of primary and follow-up spectral CT exams in oncology, and the application of appropriate spectral tools will be highlighted. RESULTS/CONCLUSIONS Spectral CT imaging offers multiple advantages over conventional CT imaging, particularly in the field of oncology. The combination of virtual native and low monoenergetic images leads to improved detection and characterization of oncologic lesions. Iodine-map images may provide a potential imaging biomarker for assessing treatment response. KEY POINTS · The most important spectral CT reconstructions for oncology imaging are virtual unenhanced, iodine map, and virtual monochromatic reconstructions.. · The combination of virtual unenhanced and low monoenergetic reconstructions leads to better detection and characterization of the vascularization of solid tumors.. · Iodine maps can be a surrogate parameter for tumor perfusion and potentially used as a therapy monitoring parameter.. · For radiotherapy planning, the relative electron density and the effective atomic number of a tissue can be calculated.. CITATION FORMAT · Sauerbeck J, Adam G, Meyer M. Onkologische Bildgebung mittels Spektral-CT. Fortschr Röntgenstr 2023; 195: 21 - 29.
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Affiliation(s)
- Julia Sauerbeck
- Department of Diagnostic and Interventional Radiology and Nuclear Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany, Hamburg, Germany
| | - Gerhard Adam
- Department of Diagnostic and Interventional Radiology and Nuclear Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany, Hamburg, Germany
| | - Mathias Meyer
- Department of Diagnostic and Interventional Radiology and Nuclear Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany, Hamburg, Germany
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Langguth P, Aludin S, Horr A, Campbell GM, Lebenatus A, Salehi Ravesh M, Schunk D, Austein F, Larsen N, Syrek H, Both M, Jansen O, Sedaghat S. Iodine uptake of adrenal glands: A novel and reliable spectral dual-layer computed tomographic-derived biomarker for acute septic shock. Eur J Radiol 2022; 156:110492. [PMID: 36108480 DOI: 10.1016/j.ejrad.2022.110492] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2022] [Revised: 08/09/2022] [Accepted: 08/15/2022] [Indexed: 11/26/2022]
Abstract
OBJECTIVES Septic shock is a potentially fatal condition. This study aims to assess whether iodine uptake and iodine density of abdominal organs on dual-layer spectral detector computed tomography (SDCT) could serve as a new imaging biomarker for patients in septic shock. METHODS Here, 95 patients who received contrast-enhanced abdominal CT examinations were included and separated into two groups: group A - septic shock; group B - no shock condition. Preselected abdominal (right and left adrenal gland, right and left kidney, infrarenal inferior vena cava (IVC), pancreas, spleen, and liver) localizations were independently evaluated by two radiologists, who measured iodine concentrations (mg/ml) and Hounsfield units (HU). RESULTS In all, 1520 measurements of iodine concentrations in mg/ml and HU were performed, with 27 patients in group A and 68 in group B. Iodine concentrations in mg/ml and HU correlated significantly in all organs measured. The corresponding correlation coefficient (r) ranged from 0.809 (pancreas) to 0.963 (right kidney). Inter-rater reliability (IRR) was very good for mg/ml (κ = 0.8; p < 0.01) and good for HU (κ = 0.773; p < 0.01) measurements. The mean iodine concentration and HU of the adrenal glands in septic and nonseptic patients was 4.88 ± 1.16 mg/ml/153 ± 36 HU and 2.67 ± 1.07 mg/ml/112 ± 41 HU, respectively. Iodine concentrations in the adrenal glands were significantly higher in group A than in group B patients (p < 0.01). The other organs remained unaffected and no significant difference was observed between patients in group A and B. Patients in group A presented significantly more often with an iodine uptake of >3.5 mg/ml of one adrenal gland (sensitivity = 0.926, specificity = 0.849, AUC = 0.951) or/and a combined concentration of >7 mg/ml of both adrenal glands (sensitivity = 0.889, specificity = 0.836, AUC = 0.928). CONCLUSION SDCT-derived iodine concentration of the adrenal glands could serve as a novel imaging biomarker for patients in acute septic shock. Our data suggest that an iodine uptake of >3.5 mg/ml of at least one adrenal gland or a combined iodine uptake of >7 mg/ml in both adrenal glands identifies patients in this condition.
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Affiliation(s)
- P Langguth
- Department for Radiology and Neuroradiology, University Hospital Schleswig-Holstein, Campus Kiel, Germany.
| | - S Aludin
- Department for Radiology and Neuroradiology, University Hospital Schleswig-Holstein, Campus Kiel, Germany
| | - A Horr
- Department for Radiology and Neuroradiology, University Hospital Schleswig-Holstein, Campus Kiel, Germany
| | | | - A Lebenatus
- Department for Radiology and Neuroradiology, University Hospital Schleswig-Holstein, Campus Kiel, Germany
| | - M Salehi Ravesh
- Department for Radiology and Neuroradiology, University Hospital Schleswig-Holstein, Campus Kiel, Germany
| | - D Schunk
- Department for Interdisciplinary Emergency, University Hospital Schleswig-Holstein, Campus Kiel, Germany
| | - F Austein
- Department of Diagnostic and Interventional Neuroradiology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - N Larsen
- Department for Radiology and Neuroradiology, University Hospital Schleswig-Holstein, Campus Kiel, Germany
| | - H Syrek
- Mediri GmbH, Heidelberg, Germany
| | - M Both
- Department for Radiology and Neuroradiology, University Hospital Schleswig-Holstein, Campus Kiel, Germany
| | - O Jansen
- Department for Radiology and Neuroradiology, University Hospital Schleswig-Holstein, Campus Kiel, Germany
| | - S Sedaghat
- Department for Radiology and Neuroradiology, University Hospital Schleswig-Holstein, Campus Kiel, Germany; Department of Radiology, University of California San Diego, San Diego, CA, United States
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Bernsen MLE, Veendrick PB, Martens JM, Pijl MEJ, Hofmeijer J, van Gorp MJ. Initial experience with dual-layer detector spectral CT for diagnosis of blood or contrast after endovascular treatment for ischemic stroke. Neuroradiology 2021; 64:69-76. [PMID: 34046731 DOI: 10.1007/s00234-021-02736-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Accepted: 05/20/2021] [Indexed: 11/30/2022]
Abstract
PURPOSE To determine whether spectral detector CT (SDCT) with a plain non-enhanced monochromatic CT, a water-weighted image after iodine removal, an iodine map, and Mono energetic images changes the diagnosis and classification of intracranial hemorrhage based on single energy CT after endovascular treatment (EVT) for ischemic stroke. METHODS Two readers evaluated single energy and SD CT data collected from 63 patients within one week after EVT. They diagnosed ICH or contrast staining, and graded ICH according to the Heidelberg and Safe Implementation of Thrombolysis in Stroke-Monitoring Study (SITS-MOST) classification. Differences in diagnosis between single energy and SD CT were tested with Pearson's chi-squared test. Diagnostic values of single energy CT were calculated. Interrater agreement was based on Cohen's Kappa. RESULTS When spectral data were added to single energy CT, the diagnosis of ICH changed in 8 CT scans (13%): in 4, the diagnosis of ICH was rejected and in 4, initially undetected ICH was diagnosed. In an additional 3 patients, the ICH grade was modified. CT alone had 88% sensitivity, 87% specificity, 88% positive diagnostic value, 87% negative diagnostic value, and 87% overall accuracy for ICH compared to SDCT. Interreader agreement on the presence of ICH was 0.84 (95% CI 0.51-0.86) for spectral CT and 0.84 (95% CI 0.73-0.97) for single energy CT. CONCLUSION SD CT after endovascular treatment contributes to the distinction between intracranial hemorrhage and contrast staining.
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Affiliation(s)
- Marie Louise E Bernsen
- Department of Radiology, Rijnstate Hospital, Wagnerlaan 55, 6815 AD, Arnhem, The Netherlands.
| | - Peter B Veendrick
- Department of Radiology, Rijnstate Hospital, Wagnerlaan 55, 6815 AD, Arnhem, The Netherlands
| | - Jasper M Martens
- Department of Radiology, Rijnstate Hospital, Wagnerlaan 55, 6815 AD, Arnhem, The Netherlands
| | - Milan E J Pijl
- Department of Radiology, Rijnstate Hospital, Wagnerlaan 55, 6815 AD, Arnhem, The Netherlands
| | - Jeannette Hofmeijer
- Department of Neurology, Rijnstate Hospital, Arnhem, The Netherlands.,Clinical Neurophysiology, Faculty of Science and Technology, University of Twente, Enschede, The Netherlands
| | - Maarten J van Gorp
- Department of Radiology, Rijnstate Hospital, Wagnerlaan 55, 6815 AD, Arnhem, The Netherlands
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Riederer I, Fingerle AA, Zimmer C, Noël PB, Makowski MR, Pfeiffer D. Potential of dual-layer spectral CT for the differentiation between hemorrhage and iodinated contrast medium in the brain after endovascular treatment of ischemic stroke patients. Clin Imaging 2021; 79:158-164. [PMID: 33962188 DOI: 10.1016/j.clinimag.2021.04.020] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Revised: 04/01/2021] [Accepted: 04/25/2021] [Indexed: 12/11/2022]
Abstract
BACKGROUND One possible complication after mechanical thrombectomy is hemorrhage. In conventional CT it is often difficult to differ between extravasation of iodinated contrast medium and blood. This differentiation, however, is essential for treatments with anticoagulants and antiplatelets. PURPOSE To evaluate dual-layer spectral Computed Tomography (DLSCT) for the differentiation between intracranial hemorrhage and iodinated contrast medium in ischemic stroke patients after mechanical thrombectomy. MATERIALS AND METHODS First, in vitro experiments were performed. Then, head CT images of 47 patients after mechanical thrombectomy were analyzed. Virtual non-contrast (VNC) images and iodine density maps (IDM) were calculated and evaluated. Region of interests (ROIs) analyses were performed. Sensitivity and specificity as well as ROC curves were calculated. RESULTS IDM and VNC images enabled clear differentiation between blood and iodine and reliable quantification of different iodine concentrations in vitro. A total of 23 hyperdense areas were detected in 13 patients, classified as hemorrhage (n = 7), iodinated contrast medium (n = 4) and a mixture of both (n = 12). Sensitivity and specificity for the detection of blood was 100%. CONCLUSION DLSCT enables differentiation between intracranial hemorrhage and iodinated contrast medium in patients after mechanical thrombectomy and might improve diagnostic imaging in post-interventional stroke patients.
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Affiliation(s)
- Isabelle Riederer
- Department of Diagnostic and Interventional Neuroradiology, Technical University of Munich, Munich, Germany.
| | - Alexander A Fingerle
- Department of Diagnostic and Interventional Radiology, Technical University of Munich, Munich, Germany
| | - Claus Zimmer
- Department of Diagnostic and Interventional Neuroradiology, Technical University of Munich, Munich, Germany
| | - Peter B Noël
- Department of Diagnostic and Interventional Radiology, Technical University of Munich, Munich, Germany; Department of Radiology, Perelman School of Medicine, University of Pennsylvania, 3400 Spruce Street, One Silverstein, Philadelphia, PA 19104, USA
| | - Marcus R Makowski
- Department of Diagnostic and Interventional Radiology, Technical University of Munich, Munich, Germany
| | - Daniela Pfeiffer
- Department of Diagnostic and Interventional Radiology, Technical University of Munich, Munich, Germany
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11
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Naveed MZ, Wang P, Lee R, Taghipour M, Brady P. Utilizing dual energy CT to distinguish blood from contrast leakage following middle meningeal artery embolization for chronic subdural hematomas. J Neurointerv Surg 2021; 13:964-967. [PMID: 33883211 DOI: 10.1136/neurintsurg-2020-016953] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2020] [Revised: 02/22/2021] [Accepted: 02/24/2021] [Indexed: 11/04/2022]
Abstract
BACKGROUND Recently, middle meningeal artery (MMA) embolization has emerged as a potential alternative treatment option for chronic subdural hematomas (SDH). Imaging following MMA embolization often shows high density material in the subdural space, usually representing contrast leakage through the dura or, less commonly, hemorrhage. These cannot be reliably differentiated on conventional CT. Dual energy CT (DECT) provides the ability to differentiate materials that otherwise appear similar on conventional CT such as blood and iodine. METHODS A retrospective review was conducted to evaluate patients who underwent MMA embolization for SDH between May 2019 and April 2020. Post-procedural head CT performed on an IQon Elite Spectral CT detector-based DECT scanner enabled two-material decomposition to separate iodine from blood. The dual energy reconstructions used included the virtual non-contrast and iodine no-water images. RESULTS Four representative illustrative cases were selected to highlight the ability of DECT to characterize new hyperdensity on head CT following MMA embolization as blood, contrast or a combination. CONCLUSIONS DECT allows objective differentiation of contrast leakage from blood following MMA embolization. This technology can obviate the need for additional follow-up scanning and prolonged patient observation, which in turn can result in reduced costs and radiation exposure to patients.
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Affiliation(s)
- Mujtaba Zaki Naveed
- Interventional Radiology, Albert Einstein Medical Center, Philadelphia, Pennsylvania, USA
| | - Peter Wang
- Diagnostic Radiology, Albert Einstein Medical Center, Philadelphia, Pennsylvania, USA
| | - Ryan Lee
- Diagnostic Radiology, Albert Einstein Medical Center, Philadelphia, Pennsylvania, USA
| | - Mehdi Taghipour
- Interventional Radiology, Albert Einstein Medical Center, Philadelphia, Pennsylvania, USA
| | - Paul Brady
- Interventional Radiology, Albert Einstein Medical Center, Philadelphia, Pennsylvania, USA
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12
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Dual-energy computed tomography in acute ischemic stroke: state-of-the-art. Eur Radiol 2020; 31:4138-4147. [PMID: 33319330 PMCID: PMC8128835 DOI: 10.1007/s00330-020-07543-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Revised: 10/31/2020] [Accepted: 11/18/2020] [Indexed: 12/15/2022]
Abstract
Abstract Dual-energy computed tomography (DECT) allows distinguishing between tissues with similar X-ray attenuation but different atomic numbers. Recent studies demonstrated that this technique has several areas of application in patients with ischemic stroke and a potential impact on patient management. After endovascular stroke therapy (EST), hyperdense areas can represent either hemorrhage or contrast staining due to blood-brain barrier disruption, which can be differentiated reliably by DECT. Further applications are improved visualization of early infarctions, compared to single-energy computed tomography, and prediction of transformation into infarction or hemorrhage in contrast-enhancing areas. In addition, DECT allows detection and evaluation of the material composition of intra-arterial clots after EST. This review summarizes the clinical state-of-the-art of DECT in patients with stroke, and features some prospects for future developments. Key points • Dual-energy computed tomography (DECT) allows differentiation between tissues with similar X-ray attenuation but differentatomic numbers. • DECT has several areas of application in patients with ischemic stroke and a potential impact on patient management. • Prospects for future developments in DECT may improve treatment decision-making.
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13
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Differentiation of hemorrhage from contrast enhancement using dual-layer spectral CT in patients transferred for acute stroke. Clin Imaging 2020; 69:75-78. [PMID: 32683139 DOI: 10.1016/j.clinimag.2020.06.046] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Revised: 06/03/2020] [Accepted: 06/26/2020] [Indexed: 11/23/2022]
Abstract
Acute stroke patients transferred to thrombectomy capable centers (TCC), undergo a CT head exam upon arrival at the TCC to evaluate for ASPECTS decay and intracranial hemorrhage. In patients who received iodinated contrast prior to transfer, parenchymal enhancement may simulate hemorrhage on this post-transfer CT. We report two cases utilizing CT spectral imaging to differentiate between parenchymal contrast enhancement and hemorrhage in this setting. TCC may consider dual-energy or dual-layer (spectral) imaging for this patient cohort.
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14
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Laukamp KR, Lennartz S, Ho V, Große Hokamp N, Zopfs D, Gupta A, Graner FP, Borggrefe J, Gilkeson R, Ramaiya N. Evaluation of the liver with virtual non-contrast: single institution study in 149 patients undergoing TAVR planning. Br J Radiol 2020; 93:20190701. [PMID: 31825655 DOI: 10.1259/bjr.20190701] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
OBJECTIVE To evaluate accuracy of virtual-non-contrast images (VNC) compared to true-unenhanced-images (TNC) for evaluation of liver attenuation acquired using spectral-detector CT (SDCT). METHODS 149 patients who underwent multiphase transcatheter-aortic-valve-replacement (TAVR) SDCT-examinations [unenhanced-chest (TNC), CT-angiography chest (CTA-chest, early arterial-phase) and abdomen (CTA-abdomen, additional early arterial-phase after a second injection of contrast media)] were retrospectively included. VNC of CTA-chest (VNC-chest) and CTA-abdomen (VNC-abdomen) were reconstructed and compared to TNC. Region of interest-based measurement of mean attenuation (Hounsfield unit, HU) was applied in the following regions: liver, spleen, abdominal aorta and paraspinal muscle. RESULTS VNC accuracy was high in the liver, spleen, abdominal aorta and muscle for abdomen-scanning. For the liver, average attenuation was 59.0 ± 9.1 HU for TNC and 72.6 ± 9.5 HU for CTA-abdomen. Liver attenuation in VNC-abdomen (59.1 ± 6.4 HU) was not significantly different from attenuation in TNC (p > 0.05). In contrast, VNC was less accurate for chest-scanning: Due to the protocol, in CTA-chest no contrast media was present in the liver parenchyma as indicated by the same attenuation in TNC (59.0 ± 9.1 HU) and CTA-chest (58.8 ± 8.9 HU, p > 0.05). Liver attenuation in VNC-chest (56.2 ± 6.4 HU, p < 0.05) was, however, significantly lower than in TNC and CTA-chest implying an artificial reduction of attenuation. CONCLUSION VNC performed well in a large cohort of TAVR-examinations yielding equivalent mean attenuations to TNC; however, application of this technique might be limited when no or very little contrast media is present in parenchyma, more precisely in an early arterial-phase of the liver. ADVANCES IN KNOWLEDGE This study showed that VNC can be reliably applied in cardiac protocols when certain limitations are considered.
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Affiliation(s)
- Kai Roman Laukamp
- Department of Radiology, University Hospitals Cleveland Medical Center, Cleveland, OH, USA.,Department of Radiology, Case Western Reserve University, Cleveland, OH, USA.,Institute for Diagnostic and Interventional Radiology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany
| | - Simon Lennartz
- Institute for Diagnostic and Interventional Radiology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany
| | - Vivian Ho
- Department of Radiology, University Hospitals Cleveland Medical Center, Cleveland, OH, USA.,Department of Radiology, Case Western Reserve University, Cleveland, OH, USA
| | - Nils Große Hokamp
- Department of Radiology, University Hospitals Cleveland Medical Center, Cleveland, OH, USA.,Department of Radiology, Case Western Reserve University, Cleveland, OH, USA.,Institute for Diagnostic and Interventional Radiology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany
| | - David Zopfs
- Institute for Diagnostic and Interventional Radiology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany
| | - Amit Gupta
- Department of Radiology, University Hospitals Cleveland Medical Center, Cleveland, OH, USA.,Department of Radiology, Case Western Reserve University, Cleveland, OH, USA
| | - Frank Philipp Graner
- Department of Radiology, University Hospitals Cleveland Medical Center, Cleveland, OH, USA.,Department of Radiology, Case Western Reserve University, Cleveland, OH, USA
| | - Jan Borggrefe
- Institute for Diagnostic and Interventional Radiology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany
| | - Robert Gilkeson
- Department of Radiology, University Hospitals Cleveland Medical Center, Cleveland, OH, USA.,Department of Radiology, Case Western Reserve University, Cleveland, OH, USA
| | - Nikhil Ramaiya
- Department of Radiology, University Hospitals Cleveland Medical Center, Cleveland, OH, USA.,Department of Radiology, Case Western Reserve University, Cleveland, OH, USA
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15
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Byrne D, Walsh JP, Schmiedeskamp H, Settecase F, Heran MKS, Niu B, Salmeen AK, Rohr B, Field TS, Murray N, Rohr A. Prediction of Hemorrhage after Successful Recanalization in Patients with Acute Ischemic Stroke: Improved Risk Stratification Using Dual-Energy CT Parenchymal Iodine Concentration Ratio Relative to the Superior Sagittal Sinus. AJNR Am J Neuroradiol 2020; 41:64-70. [PMID: 31896566 DOI: 10.3174/ajnr.a6345] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2019] [Accepted: 10/08/2019] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE Brain parenchymal hyperdensity on postthrombectomy CT in patients with acute stroke can be due to hemorrhage and/or contrast staining. We aimed to determine whether iodine concentration within contrast-stained parenchyma compared with an internal reference in the superior sagittal sinus on dual-energy CT could predict subsequent intracerebral hemorrhage. MATERIALS AND METHODS Seventy-one patients with small infarct cores (ASPECTS ≥ 7) and good endovascular recanalization (modified TICI 2b or 3) for anterior circulation large-vessel occlusion were included. Brain parenchymal iodine concentration as per dual-energy CT and the percentage of contrast staining relative to the superior sagittal sinus were recorded and correlated with the development of intracerebral hemorrhage using Mann-Whitney U and Fisher exact tests. RESULTS Forty-three of 71 patients had parenchymal hyperdensity on initial dual-energy CT. The median relative iodine concentration compared with the superior sagittal sinus was significantly higher in those with subsequent intracerebral hemorrhage (137.9% versus 109.2%, P = .007). By means of receiver operating characteristic analysis, a cutoff value of 100% (iodine concentration relative to the superior sagittal sinus) enabled identification of patients going on to develop intracerebral hemorrhage with 94.75% sensitivity, 43.4% specificity, and a likelihood ratio of 1.71. CONCLUSIONS Within our cohort of patients, the relative percentage of iodine concentration at dual-energy CT compared with the superior sagittal sinus was a reliable predictor of intracerebral hemorrhage development and may be a useful imaging biomarker for risk stratification after endovascular treatment.
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Affiliation(s)
- D Byrne
- From the Division of Neuroradiology (D.B., F.S., M.K.S.H., A.R.) .,University of British Columbia (D.B., J.P.W., F.S., M.K.S.H., B.R., T.S.F., N.M., A.R.), Vancouver, British Columbia, Canada
| | - J P Walsh
- Department of Emergency Radiology (J.P.W., N.M.).,University of British Columbia (D.B., J.P.W., F.S., M.K.S.H., B.R., T.S.F., N.M., A.R.), Vancouver, British Columbia, Canada
| | | | - F Settecase
- From the Division of Neuroradiology (D.B., F.S., M.K.S.H., A.R.).,University of British Columbia (D.B., J.P.W., F.S., M.K.S.H., B.R., T.S.F., N.M., A.R.), Vancouver, British Columbia, Canada
| | - M K S Heran
- From the Division of Neuroradiology (D.B., F.S., M.K.S.H., A.R.).,University of British Columbia (D.B., J.P.W., F.S., M.K.S.H., B.R., T.S.F., N.M., A.R.), Vancouver, British Columbia, Canada
| | - B Niu
- Vancouver Imaging (B.N.), Vancouver General Hospital, Vancouver, British Columbia, Canada
| | - A K Salmeen
- Division of Neurology (A.K.S., T.S.F.), Department of Medicine, Vancouver Stroke Program, Brain Research Center, University of British Columbia, Vancouver, British Columbia, Canada
| | - B Rohr
- University of British Columbia (D.B., J.P.W., F.S., M.K.S.H., B.R., T.S.F., N.M., A.R.), Vancouver, British Columbia, Canada
| | - T S Field
- Division of Neurology (A.K.S., T.S.F.), Department of Medicine, Vancouver Stroke Program, Brain Research Center, University of British Columbia, Vancouver, British Columbia, Canada.,University of British Columbia (D.B., J.P.W., F.S., M.K.S.H., B.R., T.S.F., N.M., A.R.), Vancouver, British Columbia, Canada
| | - N Murray
- Department of Emergency Radiology (J.P.W., N.M.).,University of British Columbia (D.B., J.P.W., F.S., M.K.S.H., B.R., T.S.F., N.M., A.R.), Vancouver, British Columbia, Canada
| | - A Rohr
- From the Division of Neuroradiology (D.B., F.S., M.K.S.H., A.R.).,University of British Columbia (D.B., J.P.W., F.S., M.K.S.H., B.R., T.S.F., N.M., A.R.), Vancouver, British Columbia, Canada
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16
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Poirot MG, Bergmans RHJ, Thomson BR, Jolink FC, Moum SJ, Gonzalez RG, Lev MH, Tan CO, Gupta R. Physics-informed Deep Learning for Dual-Energy Computed Tomography Image Processing. Sci Rep 2019; 9:17709. [PMID: 31776423 PMCID: PMC6881337 DOI: 10.1038/s41598-019-54176-0] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2019] [Accepted: 11/01/2019] [Indexed: 12/19/2022] Open
Abstract
Dual-energy CT (DECT) was introduced to address the inability of conventional single-energy computed tomography (SECT) to distinguish materials with similar absorbances but different elemental compositions. However, material decomposition algorithms based purely on the physics of the underlying attenuation process have several limitations, leading to low signal-to-noise ratio (SNR) in the derived material-specific images. To overcome these, we trained a convolutional neural network (CNN) to develop a framework to reconstruct non-contrast SECT images from DECT scans. We show that the traditional physics-based decomposition algorithms do not bring to bear the full information content of the image data. A CNN that leverages the underlying physics of the DECT image generation process as well as the anatomic information gleaned via training with actual images can generate higher fidelity processed DECT images.
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Affiliation(s)
- Maarten G Poirot
- Department of Radiology, Massachusetts General Hospital, Boston, MA, USA.,Technical Medicine, University of Twente, Enschede, The Netherlands
| | - Rick H J Bergmans
- Department of Radiology, Massachusetts General Hospital, Boston, MA, USA.,Technical Medicine, University of Twente, Enschede, The Netherlands
| | - Bart R Thomson
- Department of Radiology, Massachusetts General Hospital, Boston, MA, USA.,Technical Medicine, University of Twente, Enschede, The Netherlands
| | - Florine C Jolink
- Department of Radiology, Massachusetts General Hospital, Boston, MA, USA.,Technical Medicine, University of Twente, Enschede, The Netherlands
| | - Sarah J Moum
- Department of Radiology, Massachusetts General Hospital, Boston, MA, USA
| | - Ramon G Gonzalez
- Department of Radiology, Massachusetts General Hospital, Boston, MA, USA
| | - Michael H Lev
- Department of Radiology, Massachusetts General Hospital, Boston, MA, USA
| | - Can Ozan Tan
- Department of Radiology, Massachusetts General Hospital, Boston, MA, USA.,Harvard Medical School, Boston, MA, USA.,Cerebrovascular Research Laboratory, Spaulding Rehabilitation Hospital, Boston, MA, USA
| | - Rajiv Gupta
- Department of Radiology, Massachusetts General Hospital, Boston, MA, USA. .,Harvard Medical School, Boston, MA, USA.
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17
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Reimer RP, Flatten D, Lichtenstein T, Zopfs D, Neuhaus V, Kabbasch C, Maintz D, Borggrefe J, Große Hokamp N. Virtual Monoenergetic Images from Spectral Detector CT Enable Radiation Dose Reduction in Unenhanced Cranial CT. AJNR Am J Neuroradiol 2019; 40:1617-1623. [PMID: 31537517 DOI: 10.3174/ajnr.a6220] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2019] [Accepted: 08/05/2019] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE Our aim was to evaluate whether improved gray-white matter differentiation in cranial CT by means of 65- keV virtual monoenergetic images enables a radiation dose reduction compared to conventional images. MATERIALS AND METHODS One hundred forty consecutive patients undergoing 171 spectral detector CTs of the head between February and November 2017 (56 ± 19 years of age; male/female ratio, 56%/44%) were retrospectively included. The tube current-time product was reduced during the study period, resulting in 61, 55, and 55 patients being examined with 320, 290, and 260 mAs, respectively. All other scanning parameters were kept identical. The volume CT dose index was recorded. ROIs were placed in gray and white matter on conventional images and copied to identical positions in 65- keV virtual monoenergetic images. The contrast-to-noise ratio was calculated. Two radiologists blinded to the reconstruction technique evaluated image quality on a 5-point Likert-scale. Statistical assessment was performed using ANOVA and Wilcoxon test adjusted for multiple comparisons. RESULTS The mean volume CT dose index was 55, 49.8, and 44.7 mGy using 320, 290, and 260 mAs, respectively. Irrespective of the volume CT dose index, noise was significantly lower in 65- keV virtual monoenergetic images compared with conventional images (65- keV virtual monoenergetic images/conventional images: extraocular muscle with 49.8 mGy, 3.7 ± 1.3/5.6 ± 1.6 HU, P < .001). Noise slightly increased with a reduced radiation dose (eg, extraocular muscle in conventional images: 5.3 ± 1.4/5.6 ± 1.6/6.1 ± 2.1 HU). Overall, the contrast-to-noise ratio in 65- keV virtual monoenergetic images was superior to that in conventional images irrespective of the volume CT dose index (P < .001). Particularly, 65-keV virtual monoenergetic images with 44.7 mGy showed significantly lower noise and a higher contrast-to-noise ratio than conventional images with 55 mGy (P < .001). Subjective analysis confirmed better image quality in 65- keV virtual monoenergetic images, even using 44.7 mGy. CONCLUSIONS The 65-keV virtual monoenergetic images from spectral detector CT allow radiation dose reduction in cranial CT. While this proof of concept included a radiation dose reduction of 19%, our data suggest that even greater reduction appears achievable.
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Affiliation(s)
- R P Reimer
- From the Department of Diagnostic and Interventional Radiology, University of Cologne, Faculty of Medicine and University Hospital Cologne, Cologne, Germany
| | - D Flatten
- From the Department of Diagnostic and Interventional Radiology, University of Cologne, Faculty of Medicine and University Hospital Cologne, Cologne, Germany
| | - T Lichtenstein
- From the Department of Diagnostic and Interventional Radiology, University of Cologne, Faculty of Medicine and University Hospital Cologne, Cologne, Germany
| | - D Zopfs
- From the Department of Diagnostic and Interventional Radiology, University of Cologne, Faculty of Medicine and University Hospital Cologne, Cologne, Germany
| | - V Neuhaus
- From the Department of Diagnostic and Interventional Radiology, University of Cologne, Faculty of Medicine and University Hospital Cologne, Cologne, Germany
| | - C Kabbasch
- From the Department of Diagnostic and Interventional Radiology, University of Cologne, Faculty of Medicine and University Hospital Cologne, Cologne, Germany
| | - D Maintz
- From the Department of Diagnostic and Interventional Radiology, University of Cologne, Faculty of Medicine and University Hospital Cologne, Cologne, Germany
| | - J Borggrefe
- From the Department of Diagnostic and Interventional Radiology, University of Cologne, Faculty of Medicine and University Hospital Cologne, Cologne, Germany
| | - N Große Hokamp
- From the Department of Diagnostic and Interventional Radiology, University of Cologne, Faculty of Medicine and University Hospital Cologne, Cologne, Germany.
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18
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Metal Artifact Reduction in Routine Chest and Abdominal Examinations Using Virtual Monoenergetic Images From Spectral Detector Computed Tomography. J Comput Assist Tomogr 2019; 43:713-717. [DOI: 10.1097/rct.0000000000000901] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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