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D'Angelo T, Mastrodicasa D, Lanzafame LRM, Yel I, Koch V, Gruenewald LD, Sharma SP, Ascenti V, Micari A, Blandino A, Vogl TJ, Mazziotti S, Budde RPJ, Booz C. Optimization of window settings for coronary arteries assessment using spectral CT-derived virtual monoenergetic imaging. LA RADIOLOGIA MEDICA 2024; 129:999-1007. [PMID: 38935247 PMCID: PMC11252218 DOI: 10.1007/s11547-024-01835-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2023] [Accepted: 06/19/2024] [Indexed: 06/28/2024]
Abstract
PURPOSE To determine the optimal window setting for virtual monoenergetic images (VMI) reconstructed from dual-layer spectral coronary computed tomography angiography (DE-CCTA) datasets. MATERIAL AND METHODS 50 patients (30 males; mean age 61.1 ± 12.4 years who underwent DE-CCTA from May 2021 to June 2022 for suspected coronary artery disease, were retrospectively included. Image quality assessment was performed on conventional images and VMI reconstructions at 70 and 40 keV. Objective image quality was assessed using contrast-to-noise ratio (CNR). Two independent observers manually identified the best window settings (B-W/L) for VMI 70 and VMI 40 visualization. B-W/L were then normalized with aortic attenuation using linear regression analysis to obtain the optimized W/L (O-W/L) settings. Additionally, subjective image quality was evaluated using a 5-point Likert scale, and vessel diameters were measured to examine any potential impact of different W/L settings. RESULTS VMI 40 demonstrated higher CNR values compared to conventional and VMI 70. B-W/L settings identified were 1180/280 HU for VMI 70 and 3290/900 HU for VMI 40. Subsequent linear regression analysis yielded O-W/L settings of 1155/270 HU for VMI 70 and 3230/880 HU for VMI 40. VMI 40 O-W/L received the highest scores for each parameter compared to conventional (all p < 0.0027). Using O-W/L settings for VMI 70 and VMI 40 did not result in significant differences in vessel measurements compared to conventional images. CONCLUSION Optimization of VMI requires adjustments in W/L settings. Our results recommend W/L settings of 1155/270 HU for VMI 70 and 3230/880 HU for VMI 40.
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Affiliation(s)
- Tommaso D'Angelo
- Diagnostic and Interventional Radiology Unit, BIOMORF Department, University Hospital "Policlinico G. Martino", Via Consolare Valeria 1, 98100, Messina, Italy.
- Department of Radiology and Nuclear Medicine, Erasmus MC, Doctor Molewaterplein 40, 3015 GD, Rotterdam, The Netherlands.
| | - Domenico Mastrodicasa
- Department of Radiology, Stanford University School of Medicine, 453 Quarry Rd, MC 5659, Palo Alto, CA 94304-5659, USA
| | - Ludovica R M Lanzafame
- Diagnostic and Interventional Radiology Unit, BIOMORF Department, University Hospital "Policlinico G. Martino", Via Consolare Valeria 1, 98100, Messina, Italy
| | - Ibrahim Yel
- Division of Experimental Imaging, Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, Theodor-Stern-Kai 7, 60590, Frankfurt, Germany
| | - Vitali Koch
- Division of Experimental Imaging, Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, Theodor-Stern-Kai 7, 60590, Frankfurt, Germany
| | - Leon D Gruenewald
- Division of Experimental Imaging, Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, Theodor-Stern-Kai 7, 60590, Frankfurt, Germany
| | - Simran P Sharma
- Department of Radiology and Nuclear Medicine, Erasmus MC, Doctor Molewaterplein 40, 3015 GD, Rotterdam, The Netherlands
| | - Velio Ascenti
- Department of Radiology, Policlinico Universitario Ospedale Maggiore, Via Francesco Sforza 35, 20122, Milan, Italy
| | - Antonino Micari
- Diagnostic and Interventional Radiology Unit, BIOMORF Department, University Hospital "Policlinico G. Martino", Via Consolare Valeria 1, 98100, Messina, Italy
| | - Alfredo Blandino
- Diagnostic and Interventional Radiology Unit, BIOMORF Department, University Hospital "Policlinico G. Martino", Via Consolare Valeria 1, 98100, Messina, Italy
| | - Thomas J Vogl
- Division of Experimental Imaging, Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, Theodor-Stern-Kai 7, 60590, Frankfurt, Germany
| | - Silvio Mazziotti
- Diagnostic and Interventional Radiology Unit, BIOMORF Department, University Hospital "Policlinico G. Martino", Via Consolare Valeria 1, 98100, Messina, Italy
| | - Ricardo P J Budde
- Department of Radiology and Nuclear Medicine, Erasmus MC, Doctor Molewaterplein 40, 3015 GD, Rotterdam, The Netherlands
| | - Christian Booz
- Division of Experimental Imaging, Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, Theodor-Stern-Kai 7, 60590, Frankfurt, Germany
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Asmundo L, Rizzetto F, Srinivas Rao S, Sgrazzutti C, Vicentin I, Kambadakone A, Catalano OA, Vanzulli A. Dual-energy CT applications on liver imaging: what radiologists and radiographers should know? A systematic review. Abdom Radiol (NY) 2024:10.1007/s00261-024-04380-y. [PMID: 38811447 DOI: 10.1007/s00261-024-04380-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2024] [Revised: 05/06/2024] [Accepted: 05/11/2024] [Indexed: 05/31/2024]
Abstract
PURPOSE This review aims to provide a comprehensive summary of DECT techniques, acquisition workflows, and post-processing methods. By doing so, we aim to elucidate the advantages and disadvantages of DECT compared to conventional single-energy CT imaging. METHODS A systematic search was conducted on MEDLINE/EMBASE for DECT studies in liver imaging published between 1980 and 2024. Information regarding study design and endpoints, patient characteristics, DECT technical parameters, radiation dose, iodinated contrast agent (ICA) administration and postprocessing methods were extracted. Technical parameters, including DECT phase, field of view, pitch, collimation, rotation time, arterial phase timing (from injection), and venous timing (from injection) from the included studies were reported, along with formal narrative synthesis of main DECT applications for liver imaging. RESULTS Out of the initially identified 234 articles, 153 met the inclusion criteria. Extensive variability in acquisition parameters was observed, except for tube voltage (80/140 kVp combination reported in 50% of articles) and ICA administration (1.5 mL/kg at 3-4 mL/s, reported in 91% of articles). Radiation dose information was provided in only 40% of articles (range: 6-80 mGy), and virtual non-contrast imaging (VNC) emerged as a common strategy to reduce the radiation dose. The primary application of DECT post-processed images was in detecting focal liver lesions (47% of articles), with predominance of study focusing on hepatocellular carcinoma (HCC) (27%). Furthermore, a significant proportion of the articles (16%) focused on enhancing DECT protocols, while 15% explored metastasis detection. CONCLUSION Our review recommends using 80/140 kVp tube voltage with 1.5 mL/kg ICA at 3-4 mL/s flow rate. Post-processing should include low keV-VMI for enhanced lesion detection, IMs for tumor iodine content evaluation, and VNC for dose reduction. However, heterogeneous literature hinders protocol standardization.
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Affiliation(s)
- Luigi Asmundo
- Postgraduate School of Diagnostic and Interventional Radiology, Università degli Studi di Milano, via Festa del Perdono 7, 20122, Milan, Italy
- Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Francesco Rizzetto
- Postgraduate School of Diagnostic and Interventional Radiology, Università degli Studi di Milano, via Festa del Perdono 7, 20122, Milan, Italy.
- Department of Radiology, ASST Grande Ospedale Metropolitano Niguarda, Piazza Ospedale Maggiore 3, 20162, Milan, Italy.
| | - Shravya Srinivas Rao
- Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Cristiano Sgrazzutti
- Department of Radiology, ASST Grande Ospedale Metropolitano Niguarda, Piazza Ospedale Maggiore 3, 20162, Milan, Italy
| | - Ilaria Vicentin
- Department of Radiology, ASST Grande Ospedale Metropolitano Niguarda, Piazza Ospedale Maggiore 3, 20162, Milan, Italy
| | - Avinash Kambadakone
- Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Onofrio Antonio Catalano
- Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Angelo Vanzulli
- Department of Radiology, ASST Grande Ospedale Metropolitano Niguarda, Piazza Ospedale Maggiore 3, 20162, Milan, Italy
- Department of Oncology and Hemato-Oncology, Università degli Studi di Milano, via Festa del Perdono 7, 20122, Milan, Italy
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3
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Dar G, Goldberg SN, Levy S, Nevo A, Daud M, Sosna J, Lev-Cohain N. Optimal CT windowing on low-monoenergetic images using a simplex algorithm-based approach for abdominal inflammatory processes. Eur J Radiol 2024; 170:111262. [PMID: 38141262 DOI: 10.1016/j.ejrad.2023.111262] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2023] [Revised: 12/04/2023] [Accepted: 12/09/2023] [Indexed: 12/25/2023]
Abstract
BACKGROUND OBJECTIVES: To determine optimal window settings for conspicuity of abdominal inflammatory processes on 50 keV low-monoenergetic images derived from dual-energy spectral CT (DECT). METHODS A retrospective study of 30 patients with clinically proven pancreatitis (15/30) or pyelonephritis (15/30) with inflammatory lesions visible on DECT scans were selected to serve as reference populations. 50 keV low-monoenergetic images in the portal venous phase were iteratively evaluated by 6 abdominal radiologists in twenty-one different windows (7-350HU center; 120-580HU width), selected using a simplex optimization algorithm. Each reader graded the conspicuity of the parenchymal hypodense lesions and image background quality. Three-dimensional contour maps expressing the relationship between overall reader grade and window center and width were constructed and used to find the ideal window for inflammatory pancreatic and renal processes and the image background quality. Finally, 15 appendicitis cases were reviewed on optimal pancreas and kidney windows and the manufacturer recommended conventional abdominal window settings for conventional imaging. RESULTS Convergence to optimal windowing was achieved based upon a total of 3,780 reads (21 window settings × 6 readers × 15 cases for pancreas and kidney). Highest conspicuity grade (>4.5 ± 0.0) for pancreas inflammatory lesions was seen at 116HU/430HU, whereas hypodense pyelonephritis had highest conspicuity at 290HU/570HU. This rendered an ideal "compromise" window (>4 ± 0.2) of 150HU/450HU which differed substantially from conventional manufacturer recommended settings of 50HU/380HU (2.1 ± 1.0, p = 0.00001). Appendix mucosal enhancement was best visualized at manufacturer settings. CONCLUSIONS Optimal visualization of inflammatory processes in abdominal organs on 50 keV low-monoenergetic images may require tailored refinement of window settings.
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Affiliation(s)
- Gili Dar
- Department of Radiology, Hadassah Medical Organization and Faculty of Medicine, Hebrew University of Jerusalem, 19000 Ein Karem, Jerusalem, Israel
| | - S Nahum Goldberg
- Department of Radiology, Hadassah Medical Organization and Faculty of Medicine, Hebrew University of Jerusalem, 19000 Ein Karem, Jerusalem, Israel
| | - Shiran Levy
- Department of Radiology, Hadassah Medical Organization and Faculty of Medicine, Hebrew University of Jerusalem, 19000 Ein Karem, Jerusalem, Israel
| | - Adam Nevo
- Department of Radiology, Hadassah Medical Organization and Faculty of Medicine, Hebrew University of Jerusalem, 19000 Ein Karem, Jerusalem, Israel
| | - Marron Daud
- Department of Radiology, Hadassah Medical Organization and Faculty of Medicine, Hebrew University of Jerusalem, 19000 Ein Karem, Jerusalem, Israel
| | - Jacob Sosna
- Department of Radiology, Hadassah Medical Organization and Faculty of Medicine, Hebrew University of Jerusalem, 19000 Ein Karem, Jerusalem, Israel
| | - Naama Lev-Cohain
- Department of Radiology, Hadassah Medical Organization and Faculty of Medicine, Hebrew University of Jerusalem, 19000 Ein Karem, Jerusalem, Israel.
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Arico' FM, Trimarchi R, Portaluri A, Barilla' C, Migliaccio N, Bucolo GM, Cicero G, Sofia C, Booz C, Vogl TJ, Marino MA, Ascenti V, D'Angelo T, Mazziotti S, Ascenti G. Virtual monoenergetic dual-layer dual-energy CT images in colorectal cancer: CT diagnosis could be improved? LA RADIOLOGIA MEDICA 2023:10.1007/s11547-023-01663-0. [PMID: 37310558 DOI: 10.1007/s11547-023-01663-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Accepted: 06/05/2023] [Indexed: 06/14/2023]
Abstract
PURPOSE To compare conventional CT images and virtual monoenergetic images (VMI) at dual-layer dual-energy CT (dlDECT) in patients with colorectal cancer (CRC) through quantitative analysis and to investigate the added value of VMI. MATERIAL AND METHODS Sixty-six consecutive patients with histologically documented CRC and available VMI reconstructions were retrospectively investigated. Subsequently, forty-two patients, without any colonic disease at colonoscopy, were selected as control group. Conventional CT images and VMI reconstructions at energy levels ranging from 40 (VMI40) to 100 keV (VMI100) in 10 keV increments, were obtained from the late arterial phase. First, signal-to-noise (SNR) and contrast-to-noise (CNR) ratios were obtained to select the best VMI reconstruction. Finally, the diagnostic accuracy of conventional CT and VMI40 in late arterial phase was evaluated. RESULTS On quantitative analysis, SNR and CNR were higher for VMI40 (19.5 ± 7.7 and 11.8 ± 6.2, respectively) with statistically significant differences compared to conventional CT (P < 0.05) and all the other VMI reconstructions (P < 0.05), except for VMI50 (P > 0.05). The addition of VMI40 to conventional CT images significantly improved the area under the curve (AUC) for the diagnosis of CRC, increasing it from 0.875 to 0.943 for reader 1 (P < 0.05) and from 0.916 to 0.954 for reader 2 (P < 0.05). The improvement was greater in the less experienced radiologist (0.068) compared to the more experienced one (0.037). CONCLUSION VMI40 has showed the highest quantitative image parameters. Furthermore, the use of VMI40 can lead to a significant improvement in the diagnostic performance for detecting CRC.
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Affiliation(s)
- Francesco Marcello Arico'
- Department of Biomedical Sciences and Morphologic and Functional Imaging, Policlinico Universitario G.Martino, University of Messina, Via Consolare Valeria 1, 98123, Messina, Italy
| | - Renato Trimarchi
- Department of Biomedical Sciences and Morphologic and Functional Imaging, Policlinico Universitario G.Martino, University of Messina, Via Consolare Valeria 1, 98123, Messina, Italy.
| | - Antonio Portaluri
- Department of Biomedical Sciences and Morphologic and Functional Imaging, Policlinico Universitario G.Martino, University of Messina, Via Consolare Valeria 1, 98123, Messina, Italy
| | - Claudia Barilla'
- Department of Biomedical Sciences and Morphologic and Functional Imaging, Policlinico Universitario G.Martino, University of Messina, Via Consolare Valeria 1, 98123, Messina, Italy
| | - Nicola Migliaccio
- Department of Biomedical Sciences and Morphologic and Functional Imaging, Policlinico Universitario G.Martino, University of Messina, Via Consolare Valeria 1, 98123, Messina, Italy
| | - Giuseppe Mauro Bucolo
- Department of Biomedical Sciences and Morphologic and Functional Imaging, Policlinico Universitario G.Martino, University of Messina, Via Consolare Valeria 1, 98123, Messina, Italy
| | - Giuseppe Cicero
- Department of Biomedical Sciences and Morphologic and Functional Imaging, Policlinico Universitario G.Martino, University of Messina, Via Consolare Valeria 1, 98123, Messina, Italy
| | - Carmelo Sofia
- Department of Biomedical Sciences and Morphologic and Functional Imaging, Policlinico Universitario G.Martino, University of Messina, Via Consolare Valeria 1, 98123, Messina, Italy
| | - Christian Booz
- Division of Experimental Imaging, Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, Theodor-Stern-Kai 7, 60590, Frankfurt, Germany
| | - Thomas J Vogl
- Division of Experimental Imaging, Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, Theodor-Stern-Kai 7, 60590, Frankfurt, Germany
| | - Maria Adele Marino
- Department of Biomedical Sciences and Morphologic and Functional Imaging, Policlinico Universitario G.Martino, University of Messina, Via Consolare Valeria 1, 98123, Messina, Italy
| | - Velio Ascenti
- Postgraduate School of Radiodiagnostics, Policlinico Universitario, University of Milan, Milan, Italy
| | - Tommaso D'Angelo
- Department of Biomedical Sciences and Morphologic and Functional Imaging, Policlinico Universitario G.Martino, University of Messina, Via Consolare Valeria 1, 98123, Messina, Italy
| | - Silvio Mazziotti
- Department of Biomedical Sciences and Morphologic and Functional Imaging, Policlinico Universitario G.Martino, University of Messina, Via Consolare Valeria 1, 98123, Messina, Italy
| | - Giorgio Ascenti
- Department of Biomedical Sciences and Morphologic and Functional Imaging, Policlinico Universitario G.Martino, University of Messina, Via Consolare Valeria 1, 98123, Messina, Italy
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5
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Chang CH, Wu HN, Hsu CH, Lin HH. Virtual monochromatic imaging with projection-based material decomposition algorithm for metal artifacts reduction in photon-counting detector computed tomography. PLoS One 2023; 18:e0282900. [PMID: 36913430 PMCID: PMC10010526 DOI: 10.1371/journal.pone.0282900] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2022] [Accepted: 02/25/2023] [Indexed: 03/14/2023] Open
Abstract
Metal artifacts present a major challenge to computed tomography (CT) because they reduce the image quality in medical diagnosis and treatment. Several metal artifact reduction (MAR) methods have been proposed to address this issue in previous studies. This study aimed to synthesize a virtual monochromatic image for MAR in CT images using projection-based material decomposition (MD) algorithms. We developed a spectral micro-CT prototype system equipped with a photon-counting detector (PCD) and PCD-CT imaging simulator to assess the performances of different MAR methods. Two projection-based MD algorithms were implemented and evaluated for their MAR performances in CT images and compared with conventional sinogram inpainting MAR methods. Different parts of digital 4D-extended cardiac torso (XCAT) phantoms with metal implants were designed to simulate various real scenarios. A homemade metal artifact evaluation (MAE) phantom was used to evaluate the MAR performance in experiments. The simulated results of the XCAT phantom indicated that the projection-based virtual monochromatic CT (VMCT) images provided better image quality than the conventional MAR images without blurring the normal tissues at the position of the metal artifacts. Various quantitative indicators support this conclusion. Additionally, the experimental results of the MAE phantom reveal that projection-based VMCT images can avoid image distortion caused by metal artifacts, unlike conventional MAR methods. In regards to the projection-based VMCT images, the simulated and experimental results demonstrated that using the linear maximum likelihood estimators with an error correction look-up table algorithm yielded better MAR performance compared to that obtained using a polynomial algorithm. Furthermore, projection-based VMCT images can not only reduce metal artifacts effectively but also simultaneously prevents object blurring at the metal artifact position and image distortion of the metal implants. Hence, the CT image quality can be further improved to increase the abilities for both preoperative and postoperative assessment of metal implants.
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Affiliation(s)
- Chia-Hao Chang
- Health Physics Division, Institute of Nuclear Energy Research, Atomic Energy Council, Taoyuan, Taiwan
- Department of Biomedical Engineering and Environmental Sciences, National Tsing Hua University, Hsinchu, Taiwan
| | - Hsiang-Ning Wu
- Health Physics Division, Institute of Nuclear Energy Research, Atomic Energy Council, Taoyuan, Taiwan
| | - Ching-Han Hsu
- Department of Biomedical Engineering and Environmental Sciences, National Tsing Hua University, Hsinchu, Taiwan
| | - Hsin-Hon Lin
- Department of Medical Imaging and Radiological Sciences, Chang Gung University, Taoyuan, Taiwan
- Department of Nuclear Medicine, Keelung Chang Gung Memorial Hospital, Keelung, Taiwan
- Institute for Radiological Research, Chang Gung University/Chang Gung Memorial Hospital, Taoyuan, Taiwan
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6
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Dell’Aversana S, Ascione R, De Giorgi M, De Lucia DR, Cuocolo R, Boccalatte M, Sibilio G, Napolitano G, Muscogiuri G, Sironi S, Di Costanzo G, Cavaglià E, Imbriaco M, Ponsiglione A. Dual-Energy CT of the Heart: A Review. J Imaging 2022; 8:jimaging8090236. [PMID: 36135402 PMCID: PMC9503750 DOI: 10.3390/jimaging8090236] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 08/09/2022] [Accepted: 08/30/2022] [Indexed: 11/26/2022] Open
Abstract
Dual-energy computed tomography (DECT) represents an emerging imaging technique which consists of the acquisition of two separate datasets utilizing two different X-ray spectra energies. Several cardiac DECT applications have been assessed, such as virtual monoenergetic images, virtual non-contrast reconstructions, and iodine myocardial perfusion maps, which are demonstrated to improve diagnostic accuracy and image quality while reducing both radiation and contrast media administration. This review will summarize the technical basis of DECT and review the principal cardiac applications currently adopted in clinical practice, exploring possible future applications.
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Affiliation(s)
- Serena Dell’Aversana
- Department of Radiology, Santa Maria delle Grazie Hospital, ASL Napoli 2 Nord, 80078 Pozzuoli, Italy
- Correspondence:
| | - Raffaele Ascione
- Department of Advanced Biomedical Sciences, University of Naples Federico II, 80131 Naples, Italy
| | - Marco De Giorgi
- Department of Advanced Biomedical Sciences, University of Naples Federico II, 80131 Naples, Italy
| | - Davide Raffaele De Lucia
- Department of Advanced Biomedical Sciences, University of Naples Federico II, 80131 Naples, Italy
| | - Renato Cuocolo
- Department of Medicine, Surgery and Dentistry, University of Salerno, 84081 Baronissi, Italy
| | - Marco Boccalatte
- Coronary Care Unit, Santa Maria delle Grazie Hospital, ASL Napoli 2 Nord, 80078 Pozzuoli, Italy
| | - Gerolamo Sibilio
- Coronary Care Unit, Santa Maria delle Grazie Hospital, ASL Napoli 2 Nord, 80078 Pozzuoli, Italy
| | | | - Giuseppe Muscogiuri
- Department of Radiology, Istituto Auxologico Italiano IRCCS, San Luca Hospital, University Milano Bicocca, 20149 Milan, Italy
| | - Sandro Sironi
- Department of Radiology, Istituto Auxologico Italiano IRCCS, San Luca Hospital, University Milano Bicocca, 20149 Milan, Italy
| | - Giuseppe Di Costanzo
- Department of Radiology, Santa Maria delle Grazie Hospital, ASL Napoli 2 Nord, 80078 Pozzuoli, Italy
| | - Enrico Cavaglià
- Department of Radiology, Santa Maria delle Grazie Hospital, ASL Napoli 2 Nord, 80078 Pozzuoli, Italy
| | - Massimo Imbriaco
- Department of Advanced Biomedical Sciences, University of Naples Federico II, 80131 Naples, Italy
| | - Andrea Ponsiglione
- Department of Advanced Biomedical Sciences, University of Naples Federico II, 80131 Naples, Italy
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7
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Bette S, Decker JA, Braun FM, Becker J, Haerting M, Haeckel T, Gebhard M, Risch F, Woźnicki P, Scheurig-Muenkler C, Kroencke TJ, Schwarz F. Optimal Conspicuity of Liver Metastases in Virtual Monochromatic Imaging Reconstructions on a Novel Photon-Counting Detector CT—Effect of keV Settings and BMI. Diagnostics (Basel) 2022; 12:diagnostics12051231. [PMID: 35626387 PMCID: PMC9140684 DOI: 10.3390/diagnostics12051231] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Revised: 04/25/2022] [Accepted: 04/26/2022] [Indexed: 11/17/2022] Open
Abstract
In dual-energy CT datasets, the conspicuity of liver metastases can be enhanced by virtual monoenergetic imaging (VMI) reconstructions at low keV levels. Our study investigated whether this effect can be reproduced in photon-counting detector CT (PCD-CT) datasets. We analyzed 100 patients with liver metastases who had undergone contrast-enhanced CT of the abdomen on a PCD-CT (n = 50) or energy-integrating detector CT (EID-CT, single-energy mode, n = 50). PCD-VMI-reconstructions were performed at various keV levels. Identical regions of interest were positioned in metastases, normal liver, and other defined locations assessing image noise, tumor-to-liver ratio (TLR), and contrast-to-noise ratio (CNR). Patients were compared inter-individually. Subgroup analyses were performed according to BMI. On the PCD-CT, noise and CNR peaked at the low end of the keV spectrum. In comparison with the EID-CT, PCD-VMI-reconstructions exhibited lower image noise (at 70 keV) but higher CNR (for ≤70 keV), despite similar CTDIs. Comparing high- and low-BMI patients, CTDI-upregulation was more modest for the PCD-CT but still resulted in similar noise levels and preserved CNR, unlike the EID-CT. In conclusion, PCD-CT VMIs in oncologic patients demonstrated reduced image noise–compared to a standard EID-CT–and improved conspicuity of hypovascularized liver metastases at low keV values. Patients with higher BMIs especially benefited from constant image noise and preservation of lesion conspicuity, despite a more moderate upregulation of CTDI.
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Affiliation(s)
- Stefanie Bette
- Clinic for Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Augsburg, Stenglinstr. 2, 86156 Augsburg, Germany; (S.B.); (J.A.D.); (F.M.B.); (J.B.); (M.H.); (T.H.); (M.G.); (F.R.); (P.W.); (C.S.-M.); (F.S.)
| | - Josua A. Decker
- Clinic for Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Augsburg, Stenglinstr. 2, 86156 Augsburg, Germany; (S.B.); (J.A.D.); (F.M.B.); (J.B.); (M.H.); (T.H.); (M.G.); (F.R.); (P.W.); (C.S.-M.); (F.S.)
| | - Franziska M. Braun
- Clinic for Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Augsburg, Stenglinstr. 2, 86156 Augsburg, Germany; (S.B.); (J.A.D.); (F.M.B.); (J.B.); (M.H.); (T.H.); (M.G.); (F.R.); (P.W.); (C.S.-M.); (F.S.)
| | - Judith Becker
- Clinic for Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Augsburg, Stenglinstr. 2, 86156 Augsburg, Germany; (S.B.); (J.A.D.); (F.M.B.); (J.B.); (M.H.); (T.H.); (M.G.); (F.R.); (P.W.); (C.S.-M.); (F.S.)
| | - Mark Haerting
- Clinic for Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Augsburg, Stenglinstr. 2, 86156 Augsburg, Germany; (S.B.); (J.A.D.); (F.M.B.); (J.B.); (M.H.); (T.H.); (M.G.); (F.R.); (P.W.); (C.S.-M.); (F.S.)
| | - Thomas Haeckel
- Clinic for Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Augsburg, Stenglinstr. 2, 86156 Augsburg, Germany; (S.B.); (J.A.D.); (F.M.B.); (J.B.); (M.H.); (T.H.); (M.G.); (F.R.); (P.W.); (C.S.-M.); (F.S.)
| | - Michael Gebhard
- Clinic for Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Augsburg, Stenglinstr. 2, 86156 Augsburg, Germany; (S.B.); (J.A.D.); (F.M.B.); (J.B.); (M.H.); (T.H.); (M.G.); (F.R.); (P.W.); (C.S.-M.); (F.S.)
| | - Franka Risch
- Clinic for Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Augsburg, Stenglinstr. 2, 86156 Augsburg, Germany; (S.B.); (J.A.D.); (F.M.B.); (J.B.); (M.H.); (T.H.); (M.G.); (F.R.); (P.W.); (C.S.-M.); (F.S.)
| | - Piotr Woźnicki
- Clinic for Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Augsburg, Stenglinstr. 2, 86156 Augsburg, Germany; (S.B.); (J.A.D.); (F.M.B.); (J.B.); (M.H.); (T.H.); (M.G.); (F.R.); (P.W.); (C.S.-M.); (F.S.)
| | - Christian Scheurig-Muenkler
- Clinic for Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Augsburg, Stenglinstr. 2, 86156 Augsburg, Germany; (S.B.); (J.A.D.); (F.M.B.); (J.B.); (M.H.); (T.H.); (M.G.); (F.R.); (P.W.); (C.S.-M.); (F.S.)
| | - Thomas J. Kroencke
- Clinic for Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Augsburg, Stenglinstr. 2, 86156 Augsburg, Germany; (S.B.); (J.A.D.); (F.M.B.); (J.B.); (M.H.); (T.H.); (M.G.); (F.R.); (P.W.); (C.S.-M.); (F.S.)
- Correspondence: ; Tel.: +49-821-400-2441
| | - Florian Schwarz
- Clinic for Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Augsburg, Stenglinstr. 2, 86156 Augsburg, Germany; (S.B.); (J.A.D.); (F.M.B.); (J.B.); (M.H.); (T.H.); (M.G.); (F.R.); (P.W.); (C.S.-M.); (F.S.)
- Medical Faculty, Ludwig Maximilian University of Munich, Geschwister-Scholl-Platz 1, 80539 Munich, Germany
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8
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Zeng Y, Geng D, Zhang J. Noise-optimized virtual monoenergetic imaging technology of the third-generation dual-source computed tomography and its clinical applications. Quant Imaging Med Surg 2021; 11:4627-4643. [PMID: 34737929 DOI: 10.21037/qims-20-1196] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2020] [Accepted: 06/02/2021] [Indexed: 02/05/2023]
Abstract
The third-generation dual-source computed tomography (DSCT) is among the most advanced imaging methods. It employs noise-optimized virtual monoenergetic imaging (VMI+) technology. It uses the frequency-split method to extract high-contrast image information from low-energy images and low-noise information from images reconstructed at an optimal energy level, combining them to obtain the final image with improved quality. This review is the first to summarize the results of clinical studies that primarily and recently evaluated the VMI+ technique based on tumor, blood vessel, and other lesion classification. We aim to assist radiologists in quickly selecting the appropriate energy level when performing image reconstruction for superior image quality in clinical work and providing several ideas for future scientific research of the VMI+ technique. Presently, VMI+ reconstruction is mostly used for images of various tumors or blood vessels, including coronary plaques, coronary stents, deep vein thromboses, pulmonary embolisms (PEs), active arterial hemorrhages, and endoleaks after endovascular aneurysm repair. In addition, VMI+ has been used for imaging children's heads, liver lesions, pancreatic lacerations, and reducing metal artifacts. Regarding the reconstruction at the optimal energy level, the VMI+ technique yielded a higher image quality than the pre-optimized virtual monoenergetic imaging (VMI) technique and single-energy CT. Moreover, either low concentrations of contrast medium or low iodine injection rates can be applied before VMI+ reconstruction at a low-energy level to reduce contrast agent-related kidney injury risk. After reconstructing an image at the optimal energy level, both the image's window width and level can also be adjusted to improve the image effect's reach and diagnosis suitability. To improve image quality and lesion-imaging clarity and reduce the use of contrast agents, VMI+ reconstruction technology has been applied clinically, in which the selection of energy level is the key to the whole reconstruction process. Our review summarizes these optimal levels for radiologists' reference and suggests new ideas for the direction of future VMI+ research.
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Affiliation(s)
- Yanwei Zeng
- Department of Radiology, Huashan Hospital, Fudan University, Shanghai, China.,Institute of Functional and Molecular Medical Imaging, Fudan University, Shanghai, China.,Center for Shanghai Intelligent Imaging for Critical Brain Diseases Engineering and Technology Research, Shanghai, China
| | - Daoying Geng
- Department of Radiology, Huashan Hospital, Fudan University, Shanghai, China.,Institute of Functional and Molecular Medical Imaging, Fudan University, Shanghai, China.,Center for Shanghai Intelligent Imaging for Critical Brain Diseases Engineering and Technology Research, Shanghai, China
| | - Jun Zhang
- Department of Radiology, Huashan Hospital, Fudan University, Shanghai, China.,Institute of Functional and Molecular Medical Imaging, Fudan University, Shanghai, China.,Center for Shanghai Intelligent Imaging for Critical Brain Diseases Engineering and Technology Research, Shanghai, China
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9
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Voss BA, Khandelwal A, Wells ML, Inoue A, Venkatesh SK, Lee YS, Johnson MP, Fletcher JG. Impact of dual-energy 50-keV virtual monoenergetic images on radiologist confidence in detection of key imaging findings of small hepatocellular carcinomas using multiphase liver CT. Acta Radiol 2021; 63:1443-1452. [PMID: 34723681 DOI: 10.1177/02841851211052993] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Dual-energy virtual monoenergetic images can increase iodine signal, potentially increasing the conspicuity of hepatic masses. PURPOSE To determine if dual-energy 50-keV virtual monoenergetic images improve visualization of key imaging findings or diagnostic confidence for small (≤2 cm) hepatocellular carcinomas (HCC) at multiphase, contrast-enhanced liver computed tomography (CT). MATERIAL AND METHODS Patients with chronic liver disease underwent multiphase dual-energy CT imaging for HCC, with late arterial and delayed phase dual-energy 50-keV images reconstructed. Two non-reader subspecialized gastrointestinal (GI) radiologists established the reference standard, determining the location and diagnosis of all hepatic lesions using predetermined criteria. Three GI radiologists interpreted mixed kV CT images without or with dual-energy 50-keV images. Radiologists identified potential HCCs and rated their confidence (0-100 scales) in imaging findings of arterial enhancement, enhancing capsule, tumor washout, and LI-RADS 5 (2018) category. RESULTS In total, 45 patients (14 women; mean age = 59.5 ± 10.9 years) with chronic liver disease were included. Of them, 19 patients had 25 HCCs ≤2 cm (mean size = 1.5 ± 0.4 cm). There were 17 LI-RADS 3 and 4 lesions and 19 benign lesions. Reader confidence in imaging findings of arterial enhancement, enhancing capsule, and non-peripheral washout significantly increased with dual-energy images (P ≤ 0.022). Overall confidence in HCC diagnosis increased significantly with dual-energy 50-keV images (52.4 vs. 68.8; P = 0.001). Dual-energy images demonstrated a slight but significant decrease in overall image quality. CONCLUSION Radiologist confidence in key imaging features of small HCCs and confidence in imaging diagnosis increases with use of dual-energy 50-keV images at multiphase, contrast-enhanced liver CT.
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Affiliation(s)
| | | | | | - Akitoshi Inoue
- Department of Radiology, Mayo Clinic, Rochester, MN, USA
| | | | - Yong S Lee
- Department of Radiology, Mayo Clinic, Rochester, MN, USA
| | - Matthew P Johnson
- Biomedical Statistics and Informatics, Mayo Clinic, Rochester, MN, USA
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10
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Zopfs D, Lennartz S, Abdullayev N, Lichtenstein T, Laukamp KR, Reimer RP, Kabbasch C, Borggrefe J, Schlamann M, Neuhaus V, Große Hokamp N. Generally applicable window settings of low-keV virtual monoenergetic reconstructions in dual-layer CT-angiography of the head and neck. Quant Imaging Med Surg 2021; 11:3408-3417. [PMID: 34341719 DOI: 10.21037/qims-20-1140] [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: 10/13/2020] [Accepted: 03/25/2021] [Indexed: 11/06/2022]
Abstract
Background Increased vessel contrast in low-keV virtual monoenergetic images (VMI) in spectral detector CT angiography of the head and neck requires adaption of window settings. Aim of this study was to define generally applicable window settings of low-keV VMI. Methods Two radiologists determined ideal subjective window settings for VMI40-70 keV in 54 patients. To obtain generally applicable window settings, center and width values were modeled against the attenuation of the internal carotid artery (HUICA). This modeling was performed with and without respect to keV. Subsequently, image quality of VMI40-70 keV was assessed using the model-based determined window settings. Results With decreasing keV values, HUICA increased significantly in comparison to conventional images (CI) (P<0.05 for 40-60 keV). No significant differences between modelled and individually recorded window settings were found confirming validity of the obtained models (P values: 0.2-1.0). However, modelling with respect to keV was marginally less precise. Conclusions Window settings of low-keV VMI can be semi-automatically determined in dependency of the ICA attenuation in spectral detector CTA of the head and neck. The reported models are a promising tool to leverage the improved image quality of these images in clinical routine.
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Affiliation(s)
- David Zopfs
- Department of Diagnostic and Interventional Radiology, Faculty of Medicine and University Hospital Cologne, University Cologne, Cologne, Germany
| | - Simon Lennartz
- Department of Diagnostic and Interventional Radiology, Faculty of Medicine and University Hospital Cologne, University Cologne, Cologne, Germany.,Department of Radiology, Massachusetts General Hospital, Boston, MA, USA
| | - Nuran Abdullayev
- Department of Diagnostic and Interventional Radiology, Faculty of Medicine and University Hospital Cologne, University Cologne, Cologne, Germany
| | - Thorsten Lichtenstein
- Department of Diagnostic and Interventional Radiology, Faculty of Medicine and University Hospital Cologne, University Cologne, Cologne, Germany
| | - Kai Roman Laukamp
- Department of Diagnostic and Interventional Radiology, Faculty of Medicine and University Hospital Cologne, University Cologne, Cologne, Germany
| | - Robert Peter Reimer
- Department of Diagnostic and Interventional Radiology, Faculty of Medicine and University Hospital Cologne, University Cologne, Cologne, Germany
| | - Christoph Kabbasch
- Department of Diagnostic and Interventional Radiology, Faculty of Medicine and University Hospital Cologne, University Cologne, Cologne, Germany
| | - Jan Borggrefe
- Department of Radiology, Neuroradiology and Nuclear Medicine, Johannes Wesling University Hospital, Ruhr University Bochum, Bochum, Germany
| | - Marc Schlamann
- Department of Diagnostic and Interventional Radiology, Faculty of Medicine and University Hospital Cologne, University Cologne, Cologne, Germany
| | - Victor Neuhaus
- Department of Diagnostic and Interventional Radiology, Faculty of Medicine and University Hospital Cologne, University Cologne, Cologne, Germany
| | - Nils Große Hokamp
- Department of Diagnostic and Interventional Radiology, Faculty of Medicine and University Hospital Cologne, University Cologne, Cologne, Germany
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11
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Lenga L, Lange M, Arendt CT, Yel I, Booz C, Durden J, Leithner D, Vogl TJ, Albrecht MH, Martin SS. Can Dual-energy CT-based Virtual Monoenergetic Imaging Improve the Assessment of Hypodense Liver Metastases in Patients With Hepatic Steatosis? Acad Radiol 2021; 28:769-777. [PMID: 32446765 DOI: 10.1016/j.acra.2020.03.044] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Revised: 03/14/2020] [Accepted: 03/24/2020] [Indexed: 02/06/2023]
Abstract
RATIONALE AND OBJECTIVES To evaluate the impact of noise-optimized virtual monoenergetic imaging (VMI) on lesion demarcation and measuring accuracy of hypoattenuating liver metastases in patients with fatty liver disease compared to standard reconstructions. MATERIALS AND METHODS Twenty-eight patients (mean age 62.2 ± 7.7 years) with fatty liver disease and hypoattenuating liver metastases who underwent unenhanced and contrast-enhanced portal-venous dual-energy CT (DECT) were enrolled. Standard linearly blended and VMI series were reconstructed in 10-keV intervals. Lesion-to-parenchyma contrast-to-noise ratio (CNR) was calculated and the best VMI series was further investigated in a subjective evaluation of overall image quality and lesion demarcation. Size measurements were performed independently by measuring all hypodense lesions (n = 58) twice in a predefined sequence. Inter- and intra-rater agreement was assessed using intra-class correlation coefficient (ICC) statistics. RESULTS The calculated CNR was greatest at 40-keV VMI (4.3 ± 2.6), significantly higher compared to standard reconstructions (2.9 ± 1.9; p < 0.001). Subjective ratings for overall image quality showed no significant difference between the 2 reconstruction techniques (both medians 4; p = 0.147), while lesion margin demarcation was found to be superior for 40-keV VMI (median 5; p ≤ 0.001). Inter- (ICC, 0.98 for 40-keV VMI; ICC, 0.93 for standard reconstruction) and intra-rater (ICC, 0.99 for 40-keV VMI; ICC, 0.94 for standard image series) analysis showed an excellent agreement for lesion measurements in both reconstruction techniques. CONCLUSION Noise-optimized VMI reconstructions significantly improve contrast and lesion demarcation of hypoattenuating liver metastases in patients with the fatty liver disease compared to standard reconstruction.
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Affiliation(s)
- Lukas Lenga
- University Hospital Frankfurt, Division of Experimental Imaging, Department of Diagnostic and Interventional Radiology, Theodor-Stern-Kai 7, 60590 Frankfurt, Germany
| | - Marvin Lange
- University Hospital Frankfurt, Division of Experimental Imaging, Department of Diagnostic and Interventional Radiology, Theodor-Stern-Kai 7, 60590 Frankfurt, Germany
| | - Christophe T Arendt
- University Hospital Frankfurt, Department of Diagnostic and Interventional Radiology, Theodor-Stern-Kai 7, 60590 Frankfurt, Germany
| | - Ibrahim Yel
- University Hospital Frankfurt, Division of Experimental Imaging, Department of Diagnostic and Interventional Radiology, Theodor-Stern-Kai 7, 60590 Frankfurt, Germany
| | - Christian Booz
- University Hospital Frankfurt, Division of Experimental Imaging, Department of Diagnostic and Interventional Radiology, Theodor-Stern-Kai 7, 60590 Frankfurt, Germany
| | - James Durden
- Medical University of South Carolina, Department of Radiology and Radiological Science, 25 Courtenary Drive, 29401 Charleston, South Carolina
| | - Doris Leithner
- University Hospital Frankfurt, Department of Diagnostic and Interventional Radiology, Theodor-Stern-Kai 7, 60590 Frankfurt, Germany
| | - Thomas J Vogl
- University Hospital Frankfurt, Division of Experimental Imaging, Department of Diagnostic and Interventional Radiology, Theodor-Stern-Kai 7, 60590 Frankfurt, Germany; University Hospital Frankfurt, Department of Diagnostic and Interventional Radiology, Theodor-Stern-Kai 7, 60590 Frankfurt, Germany
| | - Moritz H Albrecht
- University Hospital Frankfurt, Division of Experimental Imaging, Department of Diagnostic and Interventional Radiology, Theodor-Stern-Kai 7, 60590 Frankfurt, Germany.
| | - Simon S Martin
- University Hospital Frankfurt, Division of Experimental Imaging, Department of Diagnostic and Interventional Radiology, Theodor-Stern-Kai 7, 60590 Frankfurt, Germany.
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12
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Impact of dose reduction and the use of an advanced model-based iterative reconstruction algorithm on spectral performance of a dual-source CT system: A task-based image quality assessment. Diagn Interv Imaging 2021; 102:405-412. [PMID: 33820752 DOI: 10.1016/j.diii.2021.03.002] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Revised: 03/04/2021] [Accepted: 03/05/2021] [Indexed: 01/14/2023]
Abstract
PURPOSE To assess the impact of dose reduction and the use of an advanced modeled iterative reconstruction algorithm (ADMIRE) on image quality in low-energy monochromatic images from a dual-source dual energy computed tomography CT (DSCT) platform. MATERIALS AND METHODS Acquisitions on an image-quality phantom were performed using DSCT equipment with 100/Sn150 kVp for four dose levels (CTDIvol: 20/11/8/5mGy). Raw data were reconstructed for six energy levels (40/50/60/70/80/100 keV) using filtered back projection and two levels of ADMIRE (A3/A5). Noise power spectrum (NPS) and task-based transfer function (TTF) were calculated on virtual monoenergetic images (VMIs). Detectability index (d') was computed to model the detection task of two enhanced iodine lesions as function of keV. RESULTS Noise-magnitude was significantly reduced between 40 to 70 keV by -56±0% (SD) (range: -56%--55%) with FBP; -56±0% (SD) (-56%--56%) with A3; and -57±1% (SD) (range: -57%--56%) with A5. The average spatial frequency of the NPS peaked at 70 keV and decreased as ADMIRE level increased. TTF values at 50% were greatest at 40 keV and shifted towards lower frequencies as the keV increased. The detectability of both lesions increased with increasing dose level and ADMIRE level. For the simulated lesion with iodine at 2mg/mL, d' values peaked at 70 keV for all reconstruction types, except for A3 at 20 mGy and A5 at 11 and 20 mGy, where d' peaked at 60 keV. For the other simulated lesion, d' values were highest at 40 keV and decreased beyond. CONCLUSION At low keV on VMIs, this study confirms that iterative reconstruction reduces the noise magnitude, improves the spatial resolution and increases the detectability of enhanced iodine lesions.
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13
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Parakh A, An C, Lennartz S, Rajiah P, Yeh BM, Simeone FJ, Sahani DV, Kambadakone AR. Recognizing and Minimizing Artifacts at Dual-Energy CT. Radiographics 2021; 41:509-523. [PMID: 33606565 DOI: 10.1148/rg.2021200049] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Dual-energy CT (DECT) is an exciting innovation in CT technology with profound capabilities to improve diagnosis and add value to patient care. Significant advances in this technology over the past decade have improved our ability to successfully adopt DECT into the clinical routine. To enable effective use of DECT, one must be aware of the pitfalls and artifacts related to this technology. Understanding the underlying technical basis of artifacts and the strategies to mitigate them requires optimization of scan protocols and parameters. The ability of radiologists and technologists to anticipate their occurrence and provide recommendations for proper selection of patients, intravenous and oral contrast media, and scan acquisition parameters is key to obtaining good-quality DECT images. In addition, choosing appropriate reconstruction algorithms such as image kernel, postprocessing parameters, and appropriate display settings is critical for preventing quantitative and qualitative interpretive errors. Therefore, knowledge of the appearances of these artifacts is essential to prevent errors and allows maximization of the potential of DECT. In this review article, the authors aim to provide a comprehensive and practical overview of possible artifacts that may be encountered at DECT across all currently available commercial clinical platforms. They also provide a pictorial overview of the diagnostic pitfalls and outline strategies for mitigating or preventing the occurrence of artifacts, when possible. The broadening scope of DECT applications necessitates up-to-date familiarity with these technologies to realize their full diagnostic potential.
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Affiliation(s)
- Anushri Parakh
- From the Department of Radiology, Massachusetts General Hospital, 55 Fruit St, White 270, Boston, MA 02114 (A.P., S.L., F.J.S., A.R.K.); Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, Calif (C.A., B.M.Y.); Institute for Diagnostic and Interventional Radiology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany (S.L.); Department of Radiology, Mayo Clinic, Rochester, Minn (P.R.); and Department of Radiology, University of Washington, Seattle, Wash (D.V.S.)
| | - Chansik An
- From the Department of Radiology, Massachusetts General Hospital, 55 Fruit St, White 270, Boston, MA 02114 (A.P., S.L., F.J.S., A.R.K.); Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, Calif (C.A., B.M.Y.); Institute for Diagnostic and Interventional Radiology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany (S.L.); Department of Radiology, Mayo Clinic, Rochester, Minn (P.R.); and Department of Radiology, University of Washington, Seattle, Wash (D.V.S.)
| | - Simon Lennartz
- From the Department of Radiology, Massachusetts General Hospital, 55 Fruit St, White 270, Boston, MA 02114 (A.P., S.L., F.J.S., A.R.K.); Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, Calif (C.A., B.M.Y.); Institute for Diagnostic and Interventional Radiology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany (S.L.); Department of Radiology, Mayo Clinic, Rochester, Minn (P.R.); and Department of Radiology, University of Washington, Seattle, Wash (D.V.S.)
| | - Prabhakar Rajiah
- From the Department of Radiology, Massachusetts General Hospital, 55 Fruit St, White 270, Boston, MA 02114 (A.P., S.L., F.J.S., A.R.K.); Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, Calif (C.A., B.M.Y.); Institute for Diagnostic and Interventional Radiology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany (S.L.); Department of Radiology, Mayo Clinic, Rochester, Minn (P.R.); and Department of Radiology, University of Washington, Seattle, Wash (D.V.S.)
| | - Benjamin M Yeh
- From the Department of Radiology, Massachusetts General Hospital, 55 Fruit St, White 270, Boston, MA 02114 (A.P., S.L., F.J.S., A.R.K.); Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, Calif (C.A., B.M.Y.); Institute for Diagnostic and Interventional Radiology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany (S.L.); Department of Radiology, Mayo Clinic, Rochester, Minn (P.R.); and Department of Radiology, University of Washington, Seattle, Wash (D.V.S.)
| | - Frank J Simeone
- From the Department of Radiology, Massachusetts General Hospital, 55 Fruit St, White 270, Boston, MA 02114 (A.P., S.L., F.J.S., A.R.K.); Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, Calif (C.A., B.M.Y.); Institute for Diagnostic and Interventional Radiology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany (S.L.); Department of Radiology, Mayo Clinic, Rochester, Minn (P.R.); and Department of Radiology, University of Washington, Seattle, Wash (D.V.S.)
| | - Dushyant V Sahani
- From the Department of Radiology, Massachusetts General Hospital, 55 Fruit St, White 270, Boston, MA 02114 (A.P., S.L., F.J.S., A.R.K.); Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, Calif (C.A., B.M.Y.); Institute for Diagnostic and Interventional Radiology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany (S.L.); Department of Radiology, Mayo Clinic, Rochester, Minn (P.R.); and Department of Radiology, University of Washington, Seattle, Wash (D.V.S.)
| | - Avinash R Kambadakone
- From the Department of Radiology, Massachusetts General Hospital, 55 Fruit St, White 270, Boston, MA 02114 (A.P., S.L., F.J.S., A.R.K.); Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, Calif (C.A., B.M.Y.); Institute for Diagnostic and Interventional Radiology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany (S.L.); Department of Radiology, Mayo Clinic, Rochester, Minn (P.R.); and Department of Radiology, University of Washington, Seattle, Wash (D.V.S.)
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14
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Parakh A, Lennartz S, An C, Rajiah P, Yeh BM, Simeone FJ, Sahani DV, Kambadakone AR. Dual-Energy CT Images: Pearls and Pitfalls. Radiographics 2021; 41:98-119. [PMID: 33411614 PMCID: PMC7853765 DOI: 10.1148/rg.2021200102] [Citation(s) in RCA: 57] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Revised: 07/10/2020] [Accepted: 07/16/2020] [Indexed: 01/10/2023]
Abstract
Dual-energy CT (DECT) is a tremendous innovation in CT technology that allows creation of numerous imaging datasets by enabling discrete acquisitions at more than one energy level. The wide range of images generated from a single DECT acquisition provides several benefits such as improved lesion detection and characterization, superior determination of material composition, reduction in the dose of iodine, and more robust quantification. Technological advances and the proliferation of various processing methods have led to the availability of diverse vendor-based DECT approaches, each with a different acquisition and image reconstruction process. The images generated from various DECT scanners differ from those from conventional single-energy CT because of differences in their acquisition techniques, material decomposition methods, image reconstruction algorithms, and postprocessing methods. DECT images such as virtual monochromatic images, material density images, and virtual unenhanced images have different imaging appearances, texture features, and quantitative capabilities. This heterogeneity creates challenges in their routine interpretation and has certain associated pitfalls. Some artifacts such as residual iodine on virtual unenhanced images and an appearance of pseudopneumatosis in a gas-distended bowel loop on material-density iodine images are specific to DECT, while others such as pseudoenhancement seen on virtual monochromatic images are also observed at single-energy CT. Recognizing the potential pitfalls associated with DECT is necessary for appropriate and accurate interpretation of the results of this increasingly important imaging tool. Online supplemental material is available for this article. ©RSNA, 2021.
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Affiliation(s)
- Anushri Parakh
- From the Department of Radiology, Massachusetts General Hospital, 55 Fruit St, White 270, Boston, MA 02114 (A.P., S.L., F.J.S., A.R.K.); Department of Radiology and Biomedical Imaging, University of California–San Francisco, San Francisco, Calif (C.A., B.M.Y.); Department of Radiology, Mayo Clinic, Rochester, Minn (P.R.); Department of Radiology, University of Washington, Seattle, Wash (D.V.S.); and Institute for Diagnostic and Interventional Radiology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany (S.L.)
| | - Simon Lennartz
- From the Department of Radiology, Massachusetts General Hospital, 55 Fruit St, White 270, Boston, MA 02114 (A.P., S.L., F.J.S., A.R.K.); Department of Radiology and Biomedical Imaging, University of California–San Francisco, San Francisco, Calif (C.A., B.M.Y.); Department of Radiology, Mayo Clinic, Rochester, Minn (P.R.); Department of Radiology, University of Washington, Seattle, Wash (D.V.S.); and Institute for Diagnostic and Interventional Radiology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany (S.L.)
| | - Chansik An
- From the Department of Radiology, Massachusetts General Hospital, 55 Fruit St, White 270, Boston, MA 02114 (A.P., S.L., F.J.S., A.R.K.); Department of Radiology and Biomedical Imaging, University of California–San Francisco, San Francisco, Calif (C.A., B.M.Y.); Department of Radiology, Mayo Clinic, Rochester, Minn (P.R.); Department of Radiology, University of Washington, Seattle, Wash (D.V.S.); and Institute for Diagnostic and Interventional Radiology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany (S.L.)
| | - Prabhakar Rajiah
- From the Department of Radiology, Massachusetts General Hospital, 55 Fruit St, White 270, Boston, MA 02114 (A.P., S.L., F.J.S., A.R.K.); Department of Radiology and Biomedical Imaging, University of California–San Francisco, San Francisco, Calif (C.A., B.M.Y.); Department of Radiology, Mayo Clinic, Rochester, Minn (P.R.); Department of Radiology, University of Washington, Seattle, Wash (D.V.S.); and Institute for Diagnostic and Interventional Radiology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany (S.L.)
| | - Benjamin M. Yeh
- From the Department of Radiology, Massachusetts General Hospital, 55 Fruit St, White 270, Boston, MA 02114 (A.P., S.L., F.J.S., A.R.K.); Department of Radiology and Biomedical Imaging, University of California–San Francisco, San Francisco, Calif (C.A., B.M.Y.); Department of Radiology, Mayo Clinic, Rochester, Minn (P.R.); Department of Radiology, University of Washington, Seattle, Wash (D.V.S.); and Institute for Diagnostic and Interventional Radiology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany (S.L.)
| | - Frank J. Simeone
- From the Department of Radiology, Massachusetts General Hospital, 55 Fruit St, White 270, Boston, MA 02114 (A.P., S.L., F.J.S., A.R.K.); Department of Radiology and Biomedical Imaging, University of California–San Francisco, San Francisco, Calif (C.A., B.M.Y.); Department of Radiology, Mayo Clinic, Rochester, Minn (P.R.); Department of Radiology, University of Washington, Seattle, Wash (D.V.S.); and Institute for Diagnostic and Interventional Radiology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany (S.L.)
| | - Dushyant V. Sahani
- From the Department of Radiology, Massachusetts General Hospital, 55 Fruit St, White 270, Boston, MA 02114 (A.P., S.L., F.J.S., A.R.K.); Department of Radiology and Biomedical Imaging, University of California–San Francisco, San Francisco, Calif (C.A., B.M.Y.); Department of Radiology, Mayo Clinic, Rochester, Minn (P.R.); Department of Radiology, University of Washington, Seattle, Wash (D.V.S.); and Institute for Diagnostic and Interventional Radiology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany (S.L.)
| | - Avinash R. Kambadakone
- From the Department of Radiology, Massachusetts General Hospital, 55 Fruit St, White 270, Boston, MA 02114 (A.P., S.L., F.J.S., A.R.K.); Department of Radiology and Biomedical Imaging, University of California–San Francisco, San Francisco, Calif (C.A., B.M.Y.); Department of Radiology, Mayo Clinic, Rochester, Minn (P.R.); Department of Radiology, University of Washington, Seattle, Wash (D.V.S.); and Institute for Diagnostic and Interventional Radiology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany (S.L.)
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15
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D'Angelo T, Lenga L, Arendt CT, Bucher AM, Peterke JL, Caruso D, Mazziotti S, Ascenti G, Blandino A, Othman AE, Martin SS, Albrecht MH, Bodelle B, Vogl TJ, Wichmann JL. Carotid and cerebrovascular dual-energy computed tomography angiography: Optimization of window settings for virtual monoenergetic imaging reconstruction. Eur J Radiol 2020; 130:109166. [PMID: 32693314 DOI: 10.1016/j.ejrad.2020.109166] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2019] [Revised: 04/25/2020] [Accepted: 07/05/2020] [Indexed: 02/08/2023]
Abstract
PURPOSE Dedicated post-processing of dual-energy computed tomography angiography (DE-CTA) datasets has been shown to allow for increased vascular contrast. The goal of our study was to define optimal window settings for displaying virtual monoenergetic images (VMI) reconstructed from dual-energy carotid and cerebrovascular DE-CTA. METHODS Fifty-seven patients who underwent clinically-indicated carotid and cerebrovascular third-generation dual-source DE-CTA were retrospectively evaluated. Standard linearly-blended (M_0.6), 70-keV traditional VMI (M70), and 40-keV noise-optimized VMI (M40+) reconstructions were analyzed. For M70 and M40+ datasets, the subjectively best window setting (width and level, B-W/L) was independently determined by two observers and subsequently related with aortic arch attenuation to calculate optimized values (O-W/L) using linear regression. Subjective evaluation of image quality (IQ) between W/L settings were assessed by two additional readers. Repeated measures analysis of variance were performed to compare W/L settings and IQ indices between M_0.6, M70, and M40 + . RESULTS B-W/L and O-W/L for M70 were 580/210 and 560/200, and for M40+ were 1630/570 and 1560/550, respectively, higher than standard DE-CTA W/L settings (450/100). Highest subjective scores were observed for M40+ regarding overall IQ (all p < 0.001). CONCLUSION Application of O-W/L settings is mandatory to optimize subjective IQ of VMI reconstructions of DE-CTA.
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Affiliation(s)
- Tommaso D'Angelo
- Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, Theodor-Stern-Kai 7, 60590, Frankfurt, Germany; Department of Biomedical Sciences and Morphological and Functional Imaging, "G. Martino" University Hospital Messina, Via Consolare Valeria 1, 98100, Messina, Italy
| | - Lukas Lenga
- Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, Theodor-Stern-Kai 7, 60590, Frankfurt, Germany
| | - Christophe T Arendt
- Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, Theodor-Stern-Kai 7, 60590, Frankfurt, Germany
| | - Andreas M Bucher
- Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, Theodor-Stern-Kai 7, 60590, Frankfurt, Germany
| | - Julia L Peterke
- Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, Theodor-Stern-Kai 7, 60590, Frankfurt, Germany
| | - Damiano Caruso
- Department of Radiological Sciences, Oncological and Pathological Sciences, "La Sapienza'' University Hospital, Latina, Italy
| | - Silvio Mazziotti
- Department of Biomedical Sciences and Morphological and Functional Imaging, "G. Martino" University Hospital Messina, Via Consolare Valeria 1, 98100, Messina, Italy
| | - Giorgio Ascenti
- Department of Biomedical Sciences and Morphological and Functional Imaging, "G. Martino" University Hospital Messina, Via Consolare Valeria 1, 98100, Messina, Italy
| | - Alfredo Blandino
- Department of Biomedical Sciences and Morphological and Functional Imaging, "G. Martino" University Hospital Messina, Via Consolare Valeria 1, 98100, Messina, Italy
| | - Ahmed E Othman
- Department for Diagnostic and Interventional Radiology, Eberhard Karls University Tuebingen, University Hospital Tübingen, Tübingen, Germany
| | - Simon S Martin
- Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, Theodor-Stern-Kai 7, 60590, Frankfurt, Germany
| | - Moritz H Albrecht
- Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, Theodor-Stern-Kai 7, 60590, Frankfurt, Germany
| | - Boris Bodelle
- Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, Theodor-Stern-Kai 7, 60590, Frankfurt, Germany
| | - Thomas J Vogl
- Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, Theodor-Stern-Kai 7, 60590, Frankfurt, Germany
| | - Julian L Wichmann
- Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, Theodor-Stern-Kai 7, 60590, Frankfurt, Germany.
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16
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Lenga L, Lange M, Arendt CT, Booz C, Yel I, Bodelle B, D'Angelo T, Hammerstingl RM, Huizinga NA, Vogl TJ, Martin SS, Albrecht MH. Measurement Reliability and Diagnostic Accuracy of Virtual Monoenergetic Dual-Energy CT in Patients with Colorectal Liver Metastases. Acad Radiol 2020; 27:e168-e175. [PMID: 31727567 DOI: 10.1016/j.acra.2019.09.020] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2019] [Revised: 09/04/2019] [Accepted: 09/12/2019] [Indexed: 12/12/2022]
Abstract
RATIONALE AND OBJECTIVES To compare dual-energy CT virtual monoenergetic images (VMI) and standard reconstructions for reliability of quantitative size measurements and diagnostic accuracy for the detection of colorectal liver metastases (CRLM). MATERIALS AND METHODS We retrospectively included 98 patients (mean age, 61.1±11.5 years) with colorectal cancer, of whom 49 subjects had CRLM. All patients underwent a portal-venous phase dual-energy CT examination. Standard linearly-blended reformats and 40-keV VMI were reconstructed. For both reconstruction techniques, two blinded readers performed measurements of CRLM twice in a preset sequence. Three additional radiologists independently assessed all liver lesions in terms of dignity (benign vs. malignant). Sensitivity, specificity and diagnostic accuracy were calculated on a per-patient basis using MRI as reference standard. Readers scored the suitability for metric measurements and their diagnostic confidence using 5-point Likert scales. Inter-rater agreement was evaluated using intraclass correlation coefficient (ICC). RESULTS Inter-rater agreement for lesion size measurements was higher for 40-keV VMI (ICC, 0.88) compared to standard linearly-blended series (ICC, 0.80). Sensitivity and diagnostic accuracy for the detection of CRLM were significantly higher for VMI at 40-keV compared to standard reconstructions (90.6% vs. 80.6%, and 89.1% vs. 81.3%; p < 0.001). Reader scores indicated that 40-keV VMI were more suitable for metric lesion measurements and provided greater diagnostic confidence compared to standard reformats (median, 5 vs. 3, and 5 vs. 4; both p < 0.001). CONCLUSION Low-keV VMI reconstructions improve reliability of quantitative size measurements and diagnostic accuracy for the assessment of CRLM compared to standard linearly-blended images.
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17
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Virtual monochromatic reconstructions of dual energy CT in abdominal trauma: optimization of energy level improves pancreas laceration conspicuity and diagnostic confidence. Emerg Radiol 2020; 28:1-7. [DOI: 10.1007/s10140-020-01791-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Accepted: 05/13/2020] [Indexed: 12/19/2022]
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18
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Li J, Yu L, Guo S, Zhao Y. Identification of the molecular mechanism and diagnostic biomarkers in the thoracic ossification of the ligamentum flavum using metabolomics and transcriptomics. BMC Mol Cell Biol 2020; 21:37. [PMID: 32404047 PMCID: PMC7218621 DOI: 10.1186/s12860-020-00280-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Accepted: 05/04/2020] [Indexed: 12/18/2022] Open
Abstract
Background To establish a metabolite fingerprint of ossification of the thoracic ligamentum flavum (OTLF) patients using liquid chromatography-mass spectrometry (LC-MS) in combination with transcriptomic data and explore the potential molecular mechanism of pathogenesis. Results The study cohort was composed of 25 patients with OTLF and 23 healthy volunteers as a control group. Thirty-seven metabolites were identified out by UPLC-MS including uric acid and hypoxanthine. Nine metabolites, including uric acid and hypoxanthine, were found with a Variable Importance in Projection (VIP) score over 1 (p < 0.05). Pathway enrichment indicated that purine metabolism pathways and the other four metabolism pathways were enriched. Transcriptomic data revealed that purine metabolism have a substantial change in gene expression of OTLF and that xanthine dehydrogenase (XDH) is the key regulatory factor. Receiver operating characteristic (ROC) analysis indicated that 17 metabolites, including uric acid, were found with an AUC value of over 0.7. Conclusion Uric acid might be the potential biomarker for OTLF and play an important role within the detailed pathway. XDH could affect purine metabolism by suppressing the expression of hypoxanthine and xanthine leading to low serum levels of uric acid in OTLF, which could be a focal point in developing new therapeutic methods for OTLF.
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Affiliation(s)
- Jiahao Li
- Department of Orthopaedic Surgery, Peking Union Medical College Hospital, Peking Union Medical College and Chinese Academy of Medical Science, No. 1 Shuaifuyuan Dongdan, Dongcheng District, 100730, Beijing, P.R. China
| | - Lingjia Yu
- Department of Orthopaedic Surgery, Peking Union Medical College Hospital, Peking Union Medical College and Chinese Academy of Medical Science, No. 1 Shuaifuyuan Dongdan, Dongcheng District, 100730, Beijing, P.R. China
| | - Shigong Guo
- National Spinal Injuries Centre, Stoke Mandeville Hospital, Aylesbury, UK
| | - Yu Zhao
- Department of Orthopaedic Surgery, Peking Union Medical College Hospital, Peking Union Medical College and Chinese Academy of Medical Science, No. 1 Shuaifuyuan Dongdan, Dongcheng District, 100730, Beijing, P.R. China.
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Kraus MS, Selo N, Kiefer LS, Esser M, Albtoush OM, Weiss J, Wichmann JL, Bamberg F, Othman AE. Advanced Virtual Monoenergetic Imaging: Improvement of Visualization and Differentiation of Intramuscular Lesions in Portal-Venous-phase Contrast-enhanced Dual-energy CT. Acad Radiol 2019; 26:1457-1465. [PMID: 30879946 DOI: 10.1016/j.acra.2019.02.014] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2018] [Revised: 02/06/2019] [Accepted: 02/08/2019] [Indexed: 12/20/2022]
Abstract
PURPOSE To evaluate the effect of advanced monoenergetic imaging (MEI+) postprocessing algorithm on the visualization of various intramuscular lesions on portal-venous-phase contrast-enhanced dual-energy computed tomography (DECT). MATERIAL AND METHODS Thirty-nine patients (64.3 ± 11.1 years; 26 males) with various intramuscular lesions ranging from malignancy, bleeding, inflammation, edematous changes, and benign neoplasms were included and underwent DECT (100/Sn150kV). Postprocessing with MEI+ technique was used to reconstruct images at four different keV levels (40, 60, 80, 100) and compared to the standard portal-venous-phase CT (CTpv) images. Image quality was assessed qualitatively (conspicuity, delineation, sharpness, noise, and confidence) by two independent readers using 5-point Likert scales, 5 = excellent; as well as quantitatively by calculating signal-to-noise ratios (SNR), contrast-to-noise ratios (CNR), and area under the receiver operating characteristic (ROC) curve (AUC) for lesion characterization. RESULTS Highest lesion enhancement and diagnostic confidence were observed in MEI+ 40 keV, with significant differences to CTpv (p < 0.001), as well as for malignant lesions (highest conspicuity, noise, and sharpness in MEI+ 40 keV; p < 0.001). CNR calculations revealed highest values for MEI+ 40 keV followed by 60 keV with significant differences to CTpv, and increasing energy levels. ROC analysis showed highest diagnostic accuracy for 40-keV MEI+ datasets regarding the detection of malignant/benign lesions with AUC values of 98.9% (95%-confidence interval: 96.5, 100) and a standard error of 1.2, further AUC values decreased to 83.6% for MEI+100. CONCLUSION MEI+ at low keV levels can significantly improve lesion detection of benign versus malignant intramuscular entities in patients undergoing portal-venous-phase DECT scans due to increased CNR.
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20
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Albrecht MH, Vogl TJ, Martin SS, Nance JW, Duguay TM, Wichmann JL, De Cecco CN, Varga-Szemes A, van Assen M, Tesche C, Schoepf UJ. Review of Clinical Applications for Virtual Monoenergetic Dual-Energy CT. Radiology 2019; 293:260-271. [DOI: 10.1148/radiol.2019182297] [Citation(s) in RCA: 71] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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21
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Sekiguchi T, Ozawa Y, Hara M, Nakagawa M, Goto T, Shibamoto Y. Visibility of the hilar lymph nodes using advanced virtual monoenergetic low-keV images for preoperative evaluation of lung cancer. Br J Radiol 2019; 92:20180734. [PMID: 31430185 DOI: 10.1259/bjr.20180734] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
OBJECTIVE The purpose of our study was to evaluate the visibility of the hilar lymph nodes (LNs) using advanced virtual monoenergetic low-keV images compared with early-phase contrast-enhanced CT. METHODS Dual energy contrast-enhanced CT was performed for pre-operative evaluation of lung cancer at 20 and 60 s after administration of contrast media in 50 patients (32 males and 18 females; mean age, 69 years). Five kinds of images (A: 20 s/120 kV; B: 60 s/40 keV; C: 60 s/50 keV; D: 60 s/120 kV; E: 60 s/100 kV) were reconstructed. We measured the CT number of the bilateral main pulmonary arteries (PAs), pulmonary veins (PVs) and hilar LNs, and evaluated the differences in CT number (Hounsfield units, HUs) between the PA/PV and LNs (PA-LN and PV-LN contrast). Artifacts from the superior vena cava (SVC) were also evaluated. RESULTS The mean PA-LN contrast (HU) was 415 in image group A, 299 in B, 180 in C, 80 in D, and 100 in E. The mean PV-LN contrasts in each group were 306, 287, 177, 78, and 99, respectively. Image group B showed the second highest PA-LN contrast following image group A. There was no significant difference in the PV-LN contrast between image groups A and B. The PA-LN and PV-LN contrasts of image groups B and C were significantly higher than those of E. SVC artifacts were lower in the delayed-phase images (Group B-E) than in Group A. CONCLUSION To evaluate the hilar LNs with a single image series, advanced virtual monoenergetic 40-keV imaging at the delayed 60-s phase seems to be the most valuable. ADVANCES IN KNOWLEDGE Advanced virtual monoenergetic image is useful for evaluation of both hilar LNs and tumors in the delayed phase without artifact derived from the streak artifact from dense contrast media in the SVC.
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Affiliation(s)
- Tomoya Sekiguchi
- Department of Radiology, Nagoya City University Graduate School of Medical Sciences
| | - Yoshiyuki Ozawa
- Department of Radiology, Nagoya City University Graduate School of Medical Sciences
| | - Masaki Hara
- Department of Radiology, Nagoya City West Medical Center
| | - Motoo Nakagawa
- Department of Radiology, Nagoya City University Graduate School of Medical Sciences
| | - Taeko Goto
- Department of Radiology, Nagoya City University Graduate School of Medical Sciences
| | - Yuta Shibamoto
- Department of Radiology, Nagoya City University Graduate School of Medical Sciences
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Iuga AI, Doerner J, Siedek F, Haneder S, Byrtus J, Luetkens JA, Maintz D, Hickethier T. Computed tomography pulmonary angiograms using a novel dual-layer spectral detector: Adjusted window settings are essential for diagnostic image quality. Medicine (Baltimore) 2019; 98:e16606. [PMID: 31415352 PMCID: PMC6831234 DOI: 10.1097/md.0000000000016606] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [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
OBJECTIVE The aim of this study was to determine optimal window settings for conventional polyenergetic and virtual monoenergetic images derived from computed tomography pulmonary angiogram (CTPA) examinations of a novel dual-layer spectral detector computed tomography system (DLCT). METHODS Monoenergetic (40 keV) and polyenergetic images of 50 CTPA examinations were calculated and the best individual window width and level (W/L) values were manually assessed. Optimized values were obtained afterwards based on regression analysis. Diameters of standardized pulmonary artery segments and subjective image quality parameters were evaluated and compared. RESULTS Attenuation and contrast-to-noise values were higher in monoenergetic than in polyenergetic images (P≤.001). Averaged best individual W/L for polyenergetic and monoenergetic were 1020/170 and 2070/480 HU, respectively.All adjusted W/L-settings varied significantly compared to standard settings (700/100 HU) and obtained higher subjective image quality scores. A systematic overestimation of artery diameters for standard window settings in monoenergetic images was observed. CONCLUSIONS Appropriate W/L-settings are required to assess polyenergetic and monoenergetic CTPA images of a novel DLCT. W/L-settings of 1020/170 HU and 2070/480 HU were found to be the best averaged values for polyenergetic and monoenergetic CTPA images, respectively.
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Affiliation(s)
- Andra-Iza Iuga
- Institute of Diagnostic and Interventional Radiology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne
| | - Jonas Doerner
- Institute of Diagnostic and Interventional Radiology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne
| | - Florian Siedek
- Institute of Diagnostic and Interventional Radiology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne
| | - Stefan Haneder
- Institute of Diagnostic and Interventional Radiology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne
| | - Jonathan Byrtus
- Institute of Diagnostic and Interventional Radiology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne
| | - Julian A. Luetkens
- Institute of Diagnostic and Interventional Radiology, University of Bonn, Bonn, Germany
| | - David Maintz
- Institute of Diagnostic and Interventional Radiology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne
| | - Tilman Hickethier
- Institute of Diagnostic and Interventional Radiology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne
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Lin YM, Chiou YY, Wu MH, Huang SS, Shen SH. Postablation assessment of hepatocellular carcinoma using dual-energy CT: Comparison of half versus standard iodine contrast medium. PLoS One 2019; 14:e0219577. [PMID: 31287838 PMCID: PMC6615706 DOI: 10.1371/journal.pone.0219577] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Accepted: 06/26/2019] [Indexed: 12/15/2022] Open
Abstract
This retrospective study was aimed to evaluate the reduced iodine load on image quality and diagnostic performance in multiphasic hepatic CT using a novel monoenergetic reconstruction algorithm (nMERA) in assessment of local tumor progression after radiofrequency ablation (RFA) of hepatocellular carcinoma (HCC). Ninety patients who underwent CT 1 month after RFA of HCC. Forty-five patients had multiphasic hepatic dual-energy CT with a half-reduced contrast medium (HRCM) of 277.5 mg I/kg. The nMERA (40-70-keV) images were reconstructed in each phase. Another 45 patients received a standard contrast medium (SCM) of 555 mg I/kg, and the images were reconstructed as a simulated 120-kVp images. Primary outcome was accuracy, sensitivity, specificity, and area under the receiver operating characteristic curve (AUC) in assessment of local tumor progression. Additional advanced assessments included the image noise, attenuation value, contrast-to-noise ratio (CNR), and subjective image quality between the groups. The accuracy, sensitivity and specificity of nMERA HRCM images were 95.7%, 100% and 93.9% for 40 keV, 95.7%, 85.7% and 100% for 50 keV, 83.0%, 42.8% and 100% for 60 keV, and 83.0%, 42.9% and 100% for 70 keV. The AUROC was 0.99, 0.99, 0.94, and 0.93 for 40-70 keV nMERA HRCM images, respectively. Compared with simulated 120-kVp SCM images, nMERA HRCM images demonstrated comparable noise at 70-keV (P < 0.05), and comparable CNR at 40- and 50-keV (P < 0.05). nMERA DECT enables the contrast medium to be reduced to up to 50% in multiphasic hepatic CT while preserving diagnostic accuracy.
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Affiliation(s)
- Yuan-Mao Lin
- Department of Radiology, Taipei Veterans General Hospital, Taipei, Taiwan
- School of Medicine, National Yang-Ming University, Taipei, Taiwan
| | - Yi-You Chiou
- Department of Radiology, Taipei Veterans General Hospital, Taipei, Taiwan
- School of Medicine, National Yang-Ming University, Taipei, Taiwan
| | - Mei-Han Wu
- School of Medicine, National Yang-Ming University, Taipei, Taiwan
- Department of Medical Imaging, Cheng Hsin General Hospital, Taipei, Taiwan
| | - Shan Su Huang
- Department of Radiology, Taipei Veterans General Hospital, Taipei, Taiwan
| | - Shu-Huei Shen
- Department of Radiology, Taipei Veterans General Hospital, Taipei, Taiwan
- School of Medicine, National Yang-Ming University, Taipei, Taiwan
- * E-mail:
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24
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Zopfs D, Laukamp KR, Pinto Dos Santos D, Sokolowski M, Große Hokamp N, Maintz D, Borggrefe J, Persigehl T, Lennartz S. Low-keV virtual monoenergetic imaging reconstructions of excretory phase spectral dual-energy CT in patients with urothelial carcinoma: A feasibility study. Eur J Radiol 2019; 116:135-143. [PMID: 31153554 DOI: 10.1016/j.ejrad.2019.05.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2019] [Revised: 05/02/2019] [Accepted: 05/05/2019] [Indexed: 01/14/2023]
Abstract
OBJECTIVES To compare objective and subjective image quality between low keV virtual monoenergetic images (VMI) of the excretory phase and conventional venous phase images derived from spectral dual-energy CT (DECT) in the assessment of urothelial carcinoma. METHODS 26 consecutive patients with histologically confirmed urothelial carcinoma who received clinically indicated venous- and excretory phase abdominal CT scans were included retrospectively. Attenuation, image noise as well as signal- and contrast-to-noise-ratio (SNR, CNR) in venous and excretory phase CT and excretory phase VMI from 40 to 70 keV were obtained from ROI-based measurements in the following regions: urothelial carcinoma, liver, pancreas, renal cortex, subcutaneous fat, renal vein/artery, portal vein, urinary bladder wall, lymph nodes, prostate/uterus. Subjective vessel contrast and delineation of primary tumor manifestations and distant metastases were rated on 5-point Likert scales. RESULTS In comparison to venous phase CT, attenuation and SNR in excretory phase VMI40keV were higher (p < 0.001), except for liver parenchyma, where they were comparable (p = 0.07 and p = 0.17, respectively). Regarding image noise, no significant difference was found between venous phase CT and excretory phase VMI40keV (p-range: 0.08-1.00), except for liver, portal vein and renal artery, where it was lower in VMI40keV (p < 0.05). CNR of urothelial carcinoma to circumjacent bladder wall was significantly higher in excretory phase VMI40keV compared to venous phase CT. Subjective vessel contrast and delineation of primary tumor and distant metastases received equivalent or higher Likert scores in excretory phase VMI40keV than in venous phase CT. CONCLUSION This feasibility study indicates that in the assessment of urothelial carcinoma, virtual monoenergetic excretory phase images at 40 keV acquired with spectral DECT could be feasible to maintain subjective and objective image quality as provided by conventional venous phase images. Still, equivalence with regards to metastatic lesion detection requires further investigation before employing this technique in a potential signal-scan, single-bolus approach.
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Affiliation(s)
- David Zopfs
- University Cologne, Faculty of Medicine and University Hospital Cologne, Department of Diagnostic and Interventional Radiology, Kerpener Straße 62, 50937, Cologne, Germany
| | - Kai Roman Laukamp
- University Cologne, Faculty of Medicine and University Hospital Cologne, Department of Diagnostic and Interventional Radiology, Kerpener Straße 62, 50937, Cologne, Germany; Department of Radiology, Case Western Reserve University and University Hospitals, 11100 Euclid Ave, Cleveland, Ohio, USA
| | - Daniel Pinto Dos Santos
- University Cologne, Faculty of Medicine and University Hospital Cologne, Department of Diagnostic and Interventional Radiology, Kerpener Straße 62, 50937, Cologne, Germany
| | - Marcel Sokolowski
- University Cologne, Faculty of Medicine and University Hospital Cologne, Department of Diagnostic and Interventional Radiology, Kerpener Straße 62, 50937, Cologne, Germany
| | - Nils Große Hokamp
- University Cologne, Faculty of Medicine and University Hospital Cologne, Department of Diagnostic and Interventional Radiology, Kerpener Straße 62, 50937, Cologne, Germany
| | - David Maintz
- University Cologne, Faculty of Medicine and University Hospital Cologne, Department of Diagnostic and Interventional Radiology, Kerpener Straße 62, 50937, Cologne, Germany
| | - Jan Borggrefe
- University Cologne, Faculty of Medicine and University Hospital Cologne, Department of Diagnostic and Interventional Radiology, Kerpener Straße 62, 50937, Cologne, Germany
| | - Thorsten Persigehl
- University Cologne, Faculty of Medicine and University Hospital Cologne, Department of Diagnostic and Interventional Radiology, Kerpener Straße 62, 50937, Cologne, Germany
| | - Simon Lennartz
- University Cologne, Faculty of Medicine and University Hospital Cologne, Department of Diagnostic and Interventional Radiology, Kerpener Straße 62, 50937, Cologne, Germany; Else Kröner Forschungskolleg Clonal Evolution in Cancer, University Hospital Cologne, Weyertal 115b, 50931, Cologne, Germany.
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25
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D'Angelo T, Cicero G, Mazziotti S, Ascenti G, Albrecht MH, Martin SS, Othman AE, Vogl TJ, Wichmann JL. Dual energy computed tomography virtual monoenergetic imaging: technique and clinical applications. Br J Radiol 2019; 92:20180546. [PMID: 30919651 DOI: 10.1259/bjr.20180546] [Citation(s) in RCA: 73] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Dual energy CT (DECT) has evolved into a commonly applied imaging technique in clinical routine due to its unique post-processing opportunities for improved evaluation of all body areas. Reconstruction of virtual monoenergetic imaging (VMI) series has shown beneficial effects for both non-contrast and contrast-enhanced DECT due to the flexibility to calculate low-keV VMI reconstructions to increase contrast and iodine attenuation, or to compute high-keV VMI reconstructions to reduce beam-hardening artefacts. The goal of this review article is to explain the technical background of VMI and noise-optimized VMI+ algorithms and to give an overview of useful clinical applications of the VMI technique in DECT of various body regions.
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Affiliation(s)
- Tommaso D'Angelo
- 1 Department of Biomedical Sciences and Morphological and Functional Imaging, Policlinico G. Martino - University Hospital Messina , Messina , Italy.,2 Department of Diagnostic and Interventional Radiology, Division of Experimental Imaging, University Hospital Frankfurt , Frankfurt , Germany
| | - Giuseppe Cicero
- 1 Department of Biomedical Sciences and Morphological and Functional Imaging, Policlinico G. Martino - University Hospital Messina , Messina , Italy
| | - Silvio Mazziotti
- 1 Department of Biomedical Sciences and Morphological and Functional Imaging, Policlinico G. Martino - University Hospital Messina , Messina , Italy
| | - Giorgio Ascenti
- 1 Department of Biomedical Sciences and Morphological and Functional Imaging, Policlinico G. Martino - University Hospital Messina , Messina , Italy
| | - Moritz H Albrecht
- 2 Department of Diagnostic and Interventional Radiology, Division of Experimental Imaging, University Hospital Frankfurt , Frankfurt , Germany
| | - Simon S Martin
- 2 Department of Diagnostic and Interventional Radiology, Division of Experimental Imaging, University Hospital Frankfurt , Frankfurt , Germany
| | - Ahmed E Othman
- 3 Department of Diagnostic and Interventional Radiology, Eberhard Karls University Tübingen , Tübingen , Germany
| | - Thomas J Vogl
- 2 Department of Diagnostic and Interventional Radiology, Division of Experimental Imaging, University Hospital Frankfurt , Frankfurt , Germany
| | - Julian L Wichmann
- 2 Department of Diagnostic and Interventional Radiology, Division of Experimental Imaging, University Hospital Frankfurt , Frankfurt , Germany
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Spectral Detector Computed Tomography Pulmonary Angiography: Improved Diagnostic Assessment and Automated Estimation of Window Settings Angiography of Pulmonary Arteries From Novel Spectral Detector Computed Tomography Provides Improved Image Quality if Settings are Adjusted. J Comput Assist Tomogr 2018; 42:850-857. [PMID: 29659429 DOI: 10.1097/rct.0000000000000743] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
OBJECTIVE This study aimed to evaluate image quality (IQ) of virtual monoenergetic images (VMIs) from novel spectral detector computed tomography angiography of the pulmonary arteries and to identify appropriate window settings for each kiloelectron volt level. MATERIALS Forty consecutive patients were included in this institutional review board-approved, Health Insurance Portability and Accountability Act-compliant study.Signal- and contrast-to-noise ratios were calculated within the pulmonary trunk, and pulmonary/lobar/segmental arteries were calculated. The IQ and diagnostic certainty were rated by 2 radiologists on 5-point scales. In addition, they recorded appropriate window settings (center/width) that were linearly modeled against attenuation within the pulmonary trunk to generate generable results. RESULTS Signal- and contrast-to-noise ratios, IQ, and diagnostic certainty are significantly increased in low-kiloelectron volt VMIs (≤60 keV). Interrater agreement was excellent (ĸ = 0.89). We developed 2 linear models (R: 0.91-0.97 and R: 0.43-0.91, respectively, P ≤ 0.01), that suggest appropriate window settings. CONCLUSIONS The VMIs from spectral detector computed tomography improve objective and subjective IQ in angiography of the pulmonary arteries, if window settings are adjusted; they can be automatically estimated using reported linear models.
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Virtual Monoenergetic Images for Diagnostic Assessment of Hypodense Lesions Within the Liver: Semiautomatic Estimation of Window Settings Using Linear Models. J Comput Assist Tomogr 2018; 42:925-931. [PMID: 30371610 DOI: 10.1097/rct.0000000000000794] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
OBJECTIVE The aim of the study was to establish the reference window settings for display of virtual monoenergetic images (VMIs) from spectral detector computed tomography when assessing hypodense liver lesions. METHODS In patients with cysts (n = 24) or metastases (n = 26), objective (HU, signal-to-noise ratio [SNR]) and subjective (overall image quality, lesion conspicuity and noise) were assessed. Furthermore, 2 readers determined optimal window center/width (C/W) for conventional images (CIs) and VMIs of 40 to 120 keV. Center/width were modeled against HUliv with and without respect to the keV level (models A and B). RESULTS Attenuation and SNR were significantly higher in low-keV VMIs and improved overall image quality and lesion conspicuity (P ≤ 0.05). Model B provided valid estimations of C/W, whereas model A was slightly less accurate. CONCLUSIONS The increase in attenuation and SNR on low-keV VMIs requires adjustment of C/W, and they can be estimated in dependency of HUliv using linear models. Reference values for standard display of VMIs of 40 to 120 keV are reported.
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Evaluation of Virtual Monoenergetic Images on Pulmonary Vasculature Using the Dual-Layer Detector-Based Spectral Computed Tomography. J Comput Assist Tomogr 2018; 42:858-865. [PMID: 29659426 DOI: 10.1097/rct.0000000000000748] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
OBJECTIVE To evaluate the ability of retrospectively generated virtual monoenergetic images (VMIs) from the detector-based spectral computed tomography (SDCT) to augment pulmonary artery enhancement in CT and if iodine map can predict the optimal monoenergetic level. METHODS The study included 79 patients with contrast-enhanced chest CT scans on an SDCT scanner. Conventional 120-kVp images and VMI from 40 to 80 keV were generated. Attenuation, noise, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) were measured at 7 different locations in the pulmonary arterial system. The iodine concentration (in milligrams per milliliter) was calculated using the iodine-density images. The overall image quality was subjectively graded on a 5-point scale, with 1 being the worst and 5 the best. Fifty-four patients with suboptimal pulmonary enhancement (<200 Hounsfield units [HU]) were then identified. From the VMIs, an ideal set was chosen that maintained mean vascular attenuation greater than 200 HU while maintaining at least diagnostically acceptable quality (ie, IQ score ≥3). At this ideal energy level, quantitative and qualitative parameters were compared with the standard 120-kVp polyenergetic study. Average iodine concentrations were correlated with the optimal keV levels used for salvaging suboptimal studies. RESULTS The mean attenuation of all the measured pulmonary arterial regions in the suboptimal cases was 136.1 ± 18.1 HU in conventional 120-kVp images. Attenuations of the VMIs at 40, 50, and 60 keV were significantly higher than conventional images measuring 357.5 ± 19.5, 243.6 ± 16.7, and 176.6 ± 15.0 HU, respectively (P < 0.001). Similar results were seen with SNR and CNR. In total, 50 studies can be salvaged, with 50 keV being the optimal energy for 21, 60 keV optimal for 17, and 40 keV optimal for 12 studies. At the optimal energy level, there were improvements of attenuation, SNR, and CNR by 71%, 63%, and 137% compared with conventional images. There was a positive correlation between iodine value and optimal reconstruction energy with a linear equation y = 5.9539x + 27.434 and R = 0.8093. CONCLUSIONS Suboptimal enhanced pulmonary arterial CT studies can be salvaged using low-energy VMI generated from the SDCT scanner. There were significant improvements of attenuation, SNR, and CNR at the optimal monoenergetic level.
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Improved visualization of hypodense liver lesions in virtual monoenergetic images from spectral detector CT: Proof of concept in a 3D-printed phantom and evaluation in 74 patients. Eur J Radiol 2018; 109:114-123. [PMID: 30527292 DOI: 10.1016/j.ejrad.2018.11.001] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2018] [Revised: 09/29/2018] [Accepted: 11/02/2018] [Indexed: 11/23/2022]
Abstract
OBJECTIVES The well-known boost of iodine associated-attenuation in low-keV virtual monoenergetic images (VMI_low) is frequently used to improve visualization of lesions and structures taking up contrast media. This study aimed to evaluate this concept in reverse. Hence to investigate if increased attenuation within the liver allows for improved visualization of little or not-enhancing lesions. METHODS A 3D-printed phantom mimicking the shape of a human liver exhibiting a lesion in its center was designed and printed. Both, parenchyma- and lesion-mimic were filled with different solutions exhibiting 80/100/120HU and 0/15/40/60HU, respectively. Further, a total of 74 contrast-enhanced studies performed on a spectral detector CT scanner (SDCT) were included in this retrospective study. Patients had MRI or follow-up proven cysts and/or hypodense metastases. VMI of 40-200 keV as well as conventional images (CI) were reconstructed. ROI were placed in lesion and parenchyma(-mimics) on CI and transferred to VMI. Signal- and contrast-to-noise ratio were calculated (S-/CNR). Further, two radiologists independently evaluated image quality. Data was statistically assessed using ANOVA or Wilcoxon-test. RESULTS In phantoms, S/CNR was significantly higher in VMI_low. The cyst-mimic in highly attenuating parenchyma-mimic on CI yielded a CNR of 6.4 ± 0.8; using VMI_40 keV, mildly hypodense lesion-mimic in poorly attenuating parenchyma-mimic exhibited a similar CNR (5.8 ± 0.9; p ≤ 0.05). The same tendency was observed in patients (cyst in CI/metastasis in VMI_40 keV: 4.4 ± 1.2/3.9 ± 1.8; p ≤ 0.05). Qualitative analysis indicated a benefit of VMI_40 keV (p ≤ 0.05). CONCLUSIONS VMI_low from SDCT allow for an improved visualization of hypodense focal liver lesions exploiting the concept of contrast blooming in reverse.
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Dual-energy CT in patients with colorectal cancer: Improved assessment of hypoattenuating liver metastases using noise-optimized virtual monoenergetic imaging. Eur J Radiol 2018; 106:184-191. [DOI: 10.1016/j.ejrad.2018.07.027] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2018] [Revised: 07/25/2018] [Accepted: 07/29/2018] [Indexed: 01/01/2023]
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Lenga L, Czwikla R, Wichmann JL, Leithner D, Albrecht MH, D'Angelo T, Arendt CT, Booz C, Hammerstingl R, Vogl TJ, Martin SS. Dual-energy CT in patients with abdominal malignant lymphoma: impact of noise-optimised virtual monoenergetic imaging on objective and subjective image quality. Clin Radiol 2018; 73:833.e19-833.e27. [PMID: 29884524 DOI: 10.1016/j.crad.2018.04.015] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2017] [Accepted: 04/25/2018] [Indexed: 12/12/2022]
Abstract
AIM To investigate the impact of noise-optimised virtual monoenergetic imaging (VMI+) reconstructions on quantitative and qualitative image parameters in patients with malignant lymphoma at dual-energy computed tomography (DECT) examinations of the abdomen. MATERIALS AND METHODS Thirty-five consecutive patients (mean age, 53.8±18.6 years; range, 21-82 years) with histologically proven malignant lymphoma of the abdomen were included retrospectively. Images were post-processed with standard linear blending (M_0.6), traditional VMI, and VMI+ technique at energy levels ranging from 40 to 100 keV in 10 keV increments. Signal-to-noise (SNR) and contrast-to-noise ratios (CNR) were objectively measured in lymphoma lesions. Image quality, lesion delineation, and image noise were rated subjectively by three blinded observers using five-point Likert scales. RESULTS Quantitative image quality parameters peaked at 40-keV VMI+ (SNR, 15.77±7.74; CNR, 18.27±8.04) with significant differences compared to standard linearly blended M_0.6 (SNR, 7.96±3.26; CNR, 13.55±3.47) and all traditional VMI series (p<0.001). Qualitative image quality assessment revealed significantly superior ratings for image quality at 60-keV VMI+ (median, 5) in comparison with all other image series (p<0.001). Assessment of lesion delineation showed the highest rating scores for 40-keV VMI+ series (median, 5), while lowest subjective image noise was found for 100-keV VMI+ reconstructions (median, 5). CONCLUSION Low-keV VMI+ reconstructions led to improved image quality and lesion delineation of malignant lymphoma lesions compared to standard image reconstruction and traditional VMI at abdominal DECT examinations.
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Affiliation(s)
- L Lenga
- Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, Frankfurt, Germany
| | - R Czwikla
- Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, Frankfurt, Germany
| | - J L Wichmann
- Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, Frankfurt, Germany.
| | - D Leithner
- Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, Frankfurt, Germany
| | - M H Albrecht
- Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, Frankfurt, Germany; Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC, USA
| | - T D'Angelo
- Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, Frankfurt, Germany; Department of Biomedical Sciences and Morphological and Functional Imaging, University Hospital Messina, Messina, Italy
| | - C T Arendt
- Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, Frankfurt, Germany
| | - C Booz
- Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, Frankfurt, Germany
| | - R Hammerstingl
- Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, Frankfurt, Germany
| | - T J Vogl
- Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, Frankfurt, Germany
| | - S S Martin
- Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, Frankfurt, Germany
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Albrecht MH, De Cecco CN, Schoepf UJ, Spandorfer A, Eid M, De Santis D, Varga-Szemes A, van Assen M, von Knebel-Doeberitz PL, Tesche C, Puntmann VO, Nagel E, Vogl TJ, Nance JW. Dual-energy CT of the heart current and future status. Eur J Radiol 2018; 105:110-118. [PMID: 30017266 DOI: 10.1016/j.ejrad.2018.05.028] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2017] [Revised: 05/17/2018] [Accepted: 05/29/2018] [Indexed: 11/19/2022]
Abstract
Several applications utilizing dual-energy cardiac CT (DECT) have recently transitioned from the realm of research into clinical workflows. DECT acquisition techniques and subsequent post-processing can provide improved qualitative analysis, allow quantitative imaging, and have the potential to decrease requisite radiation and contrast material doses. Additionally, several experimental DECT techniques are pending further investigation and may improve the diagnostic accuracy of cardiac CT and/or provide evaluation of emerging imaging biomarkers in the future. This review article will summarize the major applications utilizing DECT in diagnosis of cardiovascular disease, including both the clinically used and investigational techniques examined to date.
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Affiliation(s)
- Moritz H Albrecht
- Medical University of South Carolina, Department of Radiology and Radiological Science, Division of Cardiovascular Imaging, Charleston, SC, United States; University Hospital Frankfurt, Department of Diagnostic and Interventional Radiology, Frankfurt, Germany.
| | - Carlo N De Cecco
- Medical University of South Carolina, Department of Radiology and Radiological Science, Division of Cardiovascular Imaging, Charleston, SC, United States.
| | - U Joseph Schoepf
- Medical University of South Carolina, Department of Radiology and Radiological Science, Division of Cardiovascular Imaging, Charleston, SC, United States.
| | - Adam Spandorfer
- Medical University of South Carolina, Department of Radiology and Radiological Science, Division of Cardiovascular Imaging, Charleston, SC, United States.
| | - Marwen Eid
- Medical University of South Carolina, Department of Radiology and Radiological Science, Division of Cardiovascular Imaging, Charleston, SC, United States.
| | - Domenico De Santis
- Medical University of South Carolina, Department of Radiology and Radiological Science, Division of Cardiovascular Imaging, Charleston, SC, United States; University of Rome "Sapienza", Department of Radiological Sciences, Oncological and Pathological Sciences, Latina, Italy.
| | - Akos Varga-Szemes
- Medical University of South Carolina, Department of Radiology and Radiological Science, Division of Cardiovascular Imaging, Charleston, SC, United States.
| | - Marly van Assen
- Medical University of South Carolina, Department of Radiology and Radiological Science, Division of Cardiovascular Imaging, Charleston, SC, United States; University Medical Center Groningen, Center for Medical Imaging, Department of Radiology, Groningen, The Netherlands.
| | - Philipp L von Knebel-Doeberitz
- Medical University of South Carolina, Department of Radiology and Radiological Science, Division of Cardiovascular Imaging, Charleston, SC, United States.
| | - Christian Tesche
- Medical University of South Carolina, Department of Radiology and Radiological Science, Division of Cardiovascular Imaging, Charleston, SC, United States; Heart Center Munich-Bogenhausen, Department of Cardiology and Intensive Care Medicine, Munich, Germany.
| | - Valentina O Puntmann
- University Hospital Frankfurt, Institute of Experimental and Translational Cardiovascular Imaging, DZHK Centre for Cardiovascular Imaging, Frankfurt, Germany.
| | - Eike Nagel
- University Hospital Frankfurt, Institute of Experimental and Translational Cardiovascular Imaging, DZHK Centre for Cardiovascular Imaging, Frankfurt, Germany.
| | - Thomas J Vogl
- University Hospital Frankfurt, Department of Diagnostic and Interventional Radiology, Frankfurt, Germany.
| | - John W Nance
- Medical University of South Carolina, Department of Radiology and Radiological Science, Division of Cardiovascular Imaging, Charleston, SC, United States.
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Low kV versus dual-energy virtual monoenergetic CT imaging for proven liver lesions: what are the advantages and trade-offs in conspicuity and image quality? A pilot study. Abdom Radiol (NY) 2018; 43:1404-1412. [PMID: 28983661 DOI: 10.1007/s00261-017-1327-9] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
PURPOSE Single-energy low tube potential (SE-LTP) and dual-energy virtual monoenergetic (DE-VM) CT images both increase the conspicuity of hepatic lesions by increasing iodine signal. Our purpose was to compare the conspicuity of proven liver lesions, artifacts, and radiologist preferences in dose-matched SE-LTP and DE-VM images. METHODS Thirty-one patients with 72 proven liver lesions (21 benign, 51 malignant) underwent full-dose contrast-enhanced dual-energy CT (DECT). Half-dose images were obtained using single tube reconstruction of the dual-source SE-LTP projection data (80 or 100 kV), and by inserting noise into dual-energy projection data, with DE-VM images reconstructed from 40 to 70 keV. Three blinded gastrointestinal radiologists evaluated half-dose SE-LTP and DE-VM images, ranking and grading liver lesion conspicuity and diagnostic confidence (4-point scale) on a per-lesion basis. Image quality (noise, artifacts, sharpness) was evaluated, and overall image preference was ranked on per-patient basis. Lesion-to-liver contrast-to-noise ratio (CNR) was compared between techniques. RESULTS Mean lesion size was 1.5 ± 1.2 cm. Across the readers, the mean conspicuity ratings for 40, 45, and 50 keV half-dose DE-VM images were superior compared to other half-dose image sets (p < 0.0001). Per-lesion diagnostic confidence was similar between half-dose SE-LTP compared to half-dose DE-VM images (p ≥ 0.05; 1.19 vs. 1.24-1.32). However, SE-LTP images had less noise and artifacts and were sharper compared to DE-VM images less than 70 keV (p < 0.05). On a per-patient basis, radiologists preferred SE-LTP images the most and preferred 40-50 keV the least (p < 0.0001). Lesion CNR was also higher in SE-LTP images than DE-VM images (p < 0.01). CONCLUSION For the same applied dose level, liver lesions were more conspicuous using DE-VM compared to SE-LTP; however, SE-LTP images were preferred more than any single DE-VM energy level, likely due to lower noise and artifacts.
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Virtual Monoenergetic Images From a Novel Dual-Layer Spectral Detector Computed Tomography Scanner in Portal Venous Phase: Adjusted Window Settings Depending on Assessment Focus Are Essential for Image Interpretation. J Comput Assist Tomogr 2018; 42:350-356. [PMID: 29369944 DOI: 10.1097/rct.0000000000000711] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE We aimed to determine optimal window settings for conventional polyenergetic (PolyE) and virtual monoenergetic images (MonoE) derived from abdominal portal venous phase computed tomography (CT) examinations on a novel dual-layer spectral-detector CT (SDCT). METHODS From 50 patients, SDCT data sets MonoE at 40 kiloelectron volt as well as PolyE were reconstructed and best individual window width and level values manually were assessed separately for evaluation of abdominal arteries as well as for liver lesions. Via regression analysis, optimized individual values were mathematically calculated. Subjective image quality parameters, vessel, and liver lesion diameters were measured to determine influences of different W/L settings. RESULTS Attenuation and contrast-to-noise values were significantly higher in MonoE compared with PolyE. Compared with standard settings, almost all adjusted W/L settings varied significantly and yielded higher subjective scoring. No differences were found between manually adjusted and mathematically calculated W/L settings. CONCLUSIONS PolyE and MonoE from abdominal portal venous phase SDCT examinations require appropriate W/L settings depending on reconstruction technique and assessment focus.
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Zhao L, Li F, Zhang Z, Zhang Z, Jiang Y, Wang X, Gu J, Li D. Assessment of an advanced virtual monoenergetic reconstruction technique in cerebral and cervical angiography with third-generation dual-source CT: Feasibility of using low-concentration contrast medium. Eur Radiol 2018; 28:4379-4388. [PMID: 29654560 DOI: 10.1007/s00330-018-5407-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Revised: 02/13/2018] [Accepted: 02/22/2018] [Indexed: 12/26/2022]
Abstract
OBJECTIVES To investigate the feasibility of low-concentration contrast media (LC-CM) in cerebral and cervical dual-energy CT angiography (DE-CTA) using an advanced monoenergetic (Mono+) reconstruction technique. METHODS Sixty-five consecutive patients prospectively selected to undergo cerebral and cervical DE-CTA were randomised into two groups: 32 patients (63.7 ± 9.7 years) in the high-concentration contrast medium (HC-CM) group with iopromide 370 and 33 patients (60.7 ± 10.8 years) in the low-concentration contrast medium (LC-CM) group with iodixanol 270. Traditional monoenergetic (Mono) and Mono+ images from 40 to 100 keV levels (at 10-keV intervals) and the standard mixed (Mixed, 120 kVp equivalent) images were reconstructed. Subjective image quality parameters included the contrast-to-noise ratio (CNR) and objective image quality parameters were evaluated and compared between the two groups. RESULTS The 40-keV Mono+ images in the LC-CM group showed comparable objective CNR (common carotid arteries: 83.7 ± 24.5 vs. 78.1 ± 23.2; internal carotid arteries: 82.2 ± 26.8 vs. 76.8 ± 24.1; middle cerebral arteries: 72.5 ± 24.6 vs. 70.6 ± 19.2; all p > 0.05) and subjective image scores (3.95 ± 0.19 vs. 3.83 ± 0.35; p > 0.05) compared with Mixed images in the HC-CM group. CONCLUSION The Mono+ reconstruction technique could reduce the concentration of iodinated CM in the diagnosis of cerebral and cervical angiography. KEY POINTS • Mono+ shows decreased noise and superior CNR compared with Mono. • The 40-keV Mono+ images show the highest CNR in the LC-CM group. • The Mono+ reconstruction technique could reduce the concentration of iodinated CM.
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Affiliation(s)
- Lu Zhao
- Department of Radiology, Tianjin Medical University General Hospital, Tianjin, 300052, China
| | - Fengtan Li
- Department of Radiology, Tianjin Medical University General Hospital, Tianjin, 300052, China
| | - Zewei Zhang
- Department of Radiology, Tianjin Medical University General Hospital, Tianjin, 300052, China
| | - Zhang Zhang
- Department of Radiology, Tianjin Medical University General Hospital, Tianjin, 300052, China
| | - Yingjian Jiang
- Department of Radiology, Tianjin Medical University General Hospital, Tianjin, 300052, China
| | - Xinyu Wang
- Department of Radiology, Tianjin Medical University General Hospital, Tianjin, 300052, China
| | - Jun Gu
- Siemens Healthineers, Beijing, 100102, China
| | - Dong Li
- Department of Radiology, Tianjin Medical University General Hospital, Tianjin, 300052, China.
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Impact of noise-optimized virtual monoenergetic dual-energy computed tomography on image quality in patients with renal cell carcinoma. Eur J Radiol 2017; 97:1-7. [DOI: 10.1016/j.ejrad.2017.10.008] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2017] [Revised: 10/01/2017] [Accepted: 10/05/2017] [Indexed: 01/14/2023]
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D’Angelo T, Bucher AM, Lenga L, Arendt CT, Peterke JL, Caruso D, Mazziotti S, Blandino A, Ascenti G, Othman AE, Martin SS, Leithner D, Vogl TJ, Wichmann JL. Optimisation of window settings for traditional and noise-optimised virtual monoenergetic imaging in dual-energy computed tomography pulmonary angiography. Eur Radiol 2017; 28:1393-1401. [DOI: 10.1007/s00330-017-5059-6] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2017] [Revised: 08/16/2017] [Accepted: 09/05/2017] [Indexed: 12/30/2022]
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Dual-energy computed tomography in patients with cutaneous malignant melanoma: Comparison of noise-optimized and traditional virtual monoenergetic imaging. Eur J Radiol 2017; 95:1-8. [DOI: 10.1016/j.ejrad.2017.07.017] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2017] [Revised: 06/27/2017] [Accepted: 07/19/2017] [Indexed: 02/06/2023]
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Fu W, Marin D, Ramirez-Giraldo JC, Choudhury KR, Solomon J, Schabel C, Patel BN, Samei E. Optimizing window settings for improved presentation of virtual monoenergetic images in dual-energy computed tomography. Med Phys 2017; 44:5686-5696. [PMID: 28777467 DOI: 10.1002/mp.12501] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2016] [Revised: 06/06/2017] [Accepted: 07/20/2017] [Indexed: 12/21/2022] Open
Abstract
PURPOSE Dual-energy computed tomography virtual monoenergetic imaging (VMI) at 40 keV exhibits superior contrast-to-noise ratio (CNR), although practicing radiologists do not consistently prefer it over VMI at 70 keV due to high perceivable noise. We hypothesize that the presentation of 40 keV VMI may be compromised using window settings (i.e., window-and-level values [W-L values]) designed for conventional single-energy CT. This study aimed to devise optimum window settings that reduce the apparent noise and utilize the high CNR of 40 keV VMI, in order to improve the conspicuity of hypervascular liver lesions. MATERIALS AND METHODS Three W-L value adjustment methods were investigated to alter the presentation of 40 keV VMI. To harness the high CNR of 40 keV VMI, the methods were designed to achieve (a) liver histogram distribution, (b) lesion-to-liver contrast, or (c) liver background noise comparable to those perceived in 70 keV VMI. This IRB-approved study included 18 patient abdominal datasets reconstructed at 40 and 70 keV. For each patient, the W-L values were determined using the three methods. For each of the images with default or adjusted W-L values, the noise, contrast, and CNR were calculated in terms of both display space and native CT number (referred to as HU) space. An observer study was performed to compare the 40 keV images with the three adjusted W-L values, and 40 and 70 keV images with default W-L values in terms of noise, contrast, and diagnostic preference. A comparison was also made in terms of the applicability of using patient-specific or patient-averaged W-L values. RESULTS Using the default W-L values, 40 keV VMI exhibited higher HU CNR than 70 keV VMI by 24.6 ± 14.9% (P < 0.001) but lower display CNR by 38.0 ± 16.4% (P < 0.001). Using adjusted W-L values, 40 keV images showed increased display CNR as compared to 70 keV images, by 21.2 ± 13.1%, 17.4 ± 13.6%, and 24.2 ± 15.9% (P < 0.001) for histogram-, noise-, and contrast equalization methods, respectively. The 40 keV images with all three W-L value adjustment methods showed improved perceived conspicuity (CNR) of liver presentation by 103-120% (P < 0.001), as compared to default W-L values. The qualitative observer study revealed that 40 keV images with noise- and histogram-equalized W-L values were the most preferred, followed by 40 keV images with contrast-equalized W-L values and 70 keV images with default W-L values. The 40 keV images with default W-L values were the least preferred. Patient-specific W-L values offered similar results to those of patient-averaged W-L values. CONCLUSION The adjusted W-L values can significantly improve the perception of VMI dataset image quality by improving the actual display CNR.
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Affiliation(s)
- Wanyi Fu
- Department of Electrical and Computer Engineering, and Carl E. Ravin Advanced Imaging Laboratories, Department of Radiology, Duke University, Durham, NC, 27705, USA
| | - Daniele Marin
- Department of Radiology, Duke University Medical Center, Durham, NC, 27705, USA
| | | | - Kingshuk Roy Choudhury
- Carl E. Ravin Advanced Imaging Laboratories, Department of Radiology, Duke University, Durham, NC, 27705, USA
| | - Justin Solomon
- Carl E. Ravin Advanced Imaging Laboratories, Clinical Imaging Physics Group, Department of Radiology, Duke University Medical Center, Durham, NC, 27705, USA
| | - Christoph Schabel
- Department of Radiology, Duke University Medical Center, Durham, NC, 27705, USA
| | - Bhavik N Patel
- Department of Radiology, Duke University Medical Center, Durham, NC, 27705, USA
| | - Ehsan Samei
- Carl E. Ravin Advanced Imaging Laboratories, Medical Physics Graduate Program, Department of Radiology, and Departments of Physics, Biomedical Engineering, and Electrical and Computer Engineering, Duke University, Durham, NC, 27705, USA
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Effect of Noise-Optimized Monoenergetic Postprocessing on Diagnostic Accuracy for Detecting Incidental Pulmonary Embolism in Portal-Venous Phase Dual-Energy Computed Tomography. Invest Radiol 2017; 52:142-147. [DOI: 10.1097/rli.0000000000000319] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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Martin SS, Pfeifer S, Wichmann JL, Albrecht MH, Leithner D, Lenga L, Scholtz JE, Vogl TJ, Bodelle B. Noise-optimized virtual monoenergetic dual-energy computed tomography: optimization of kiloelectron volt settings in patients with gastrointestinal stromal tumors. Abdom Radiol (NY) 2017; 42:718-726. [PMID: 27999889 DOI: 10.1007/s00261-016-1011-5] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
PURPOSE The aim of this study was to evaluate the impact of a noise-optimized virtual monoenergetic imaging (VMI+) reconstruction technique on quantitative and qualitative image analysis in patients with gastrointestinal stromal tumors (GISTs) at dual-energy computed tomography (DECT) of the abdomen. METHODS Forty-five DECT datasets of 21 patients (14 men; 63.7 ± 9.2 years) with GISTs were reconstructed with the standard linearly blended (M_0.6) and VMI+ and traditional virtual monoenergetic (VMI) algorithm in 10-keV increments from 40 to 100 keV. Attenuation measurements were performed in GIST lesions and abdominal metastases to calculate objective signal-to-noise (SNR) and contrast-to-noise ratios (CNR). Five-point scales were used to evaluate overall image quality, lesion delineation, image sharpness, and image noise. RESULTS Quantitative image parameters peaked at 40-keV VMI+ series (SNR 27.8 ± 13.0; CNR 26.3 ± 12.7), significantly superior to linearly blended (SNR 16.8 ± 7.3; CNR 13.6 ± 6.9) and all VMI series (all P < 0.001). Qualitative image parameters were highest for 60-keV VMI+ reconstructions regarding overall image quality and image sharpness (median 5, respectively; P ≤ 0.023). Qualitative assessment of lesion delineation peaked in 40 and 50-keV VMI+ series (median 5, respectively). Image noise was superior in 90 and 100-keV VMI and VMI+ reconstructions (all medians 5). CONCLUSIONS Low-keV VMI+ reconstructions significantly increase SNR and CNR of GISTs and improve quantitative and qualitative image quality of abdominal DECT datasets compared to traditional VMI and standard linearly blended image series.
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Affiliation(s)
- Simon S Martin
- Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, Theodor-Stern-Kai 7, 60590, Frankfurt, Germany
| | - Sophia Pfeifer
- Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, Theodor-Stern-Kai 7, 60590, Frankfurt, Germany
| | - Julian L Wichmann
- Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, Theodor-Stern-Kai 7, 60590, Frankfurt, Germany.
| | - Moritz H Albrecht
- Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, Theodor-Stern-Kai 7, 60590, Frankfurt, Germany
- Department of Radiology and Radiological Science, Medical University of South Carolina, Charleston, SC, USA
| | - Doris Leithner
- Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, Theodor-Stern-Kai 7, 60590, Frankfurt, Germany
| | - Lukas Lenga
- Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, Theodor-Stern-Kai 7, 60590, Frankfurt, Germany
| | - Jan-Erik Scholtz
- Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, Theodor-Stern-Kai 7, 60590, Frankfurt, Germany
- Cardiac MR PET CT Program, Harvard Medical School, Massachusetts General Hospital, Boston, MA, USA
| | - Thomas J Vogl
- Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, Theodor-Stern-Kai 7, 60590, Frankfurt, Germany
| | - Boris Bodelle
- Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, Theodor-Stern-Kai 7, 60590, Frankfurt, Germany
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Spinal dual-energy computed tomography: improved visualisation of spinal tumorous growth with a noise-optimised advanced monoenergetic post-processing algorithm. Neuroradiology 2016; 58:1093-1102. [DOI: 10.1007/s00234-016-1733-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2016] [Accepted: 07/19/2016] [Indexed: 01/14/2023]
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