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Magnetta MJ, Schieda N, Murphy P, Miller FH. Accumulation of iodine or other similar K-edge equivalent element within renal cysts mimics enhancing masses at single-phase dual-energy CT. Br J Radiol 2023; 96:20221079. [PMID: 36802978 PMCID: PMC10078865 DOI: 10.1259/bjr.20221079] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Revised: 01/31/2023] [Accepted: 02/06/2023] [Indexed: 02/22/2023] Open
Abstract
OBJECTIVE To describe instances of iodine, or other element with similar K-edge to iodine, accumulating in benign renal cysts and simulating solid renal masses (SRM) at single-phase contrast-enhanced (CE) dual-energy CT (DECT). METHODS During the course of routine clinical practice, instances of benign renal cysts (reference standard true non-contrast enhanced CT [NCCT] homogeneous attenuation <10 HU and not enhancing, or MRI) simulating SRM at follow-up single-phase CE-DECT due to iodine (or other element) accumulation were documented in two institutions over a 3-month observation period in 2021. RESULTS Five Bosniak one renal cysts (12 ± 7 mm) in five patients changed nature on follow-up imaging simulating SRM at CE-DECT. At time of DECT, cyst attenuation on true NCCT (mean 91 ± 25 HU [Range 56-120]) was significantly higher compared to virtual NCCT (mean 11 ± 22 HU [-23-30], p = 0.003) and all five cysts showed internal iodine content on DECT iodine maps with concentration >1.9 mg ml-1 (mean 8.2 ± 7.6 mg ml-1 [2.8-20.9]). CONCLUSION The accumulation of iodine, or other element with similar K-edge to iodine, in benign renal cysts could simulate enhancing renal masses at single-phase contrast-enhanced DECT.
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Affiliation(s)
- Michael J Magnetta
- Department of Radiology, Northwestern Memorial Hospital, Northwestern University, Chicago, IL, USA
| | - Nicola Schieda
- Department of Medical Imaging, The Ottawa Hospital, The University of Ottawa, 1053 Carling Ave, Ottawa, Canada
| | - Patrick Murphy
- Department of Radiology, Northwestern Memorial Hospital, Northwestern University, Chicago, IL, USA
| | - Frank H Miller
- Department of Radiology, Northwestern Memorial Hospital, Northwestern University, Chicago, IL, USA
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Pourvaziri A, Mojtahed A, Hahn PF, Gee MS, Kambadakone A, Sahani DV. Renal lesion characterization: clinical utility of single-phase dual-energy CT compared to MRI and dual-phase single-energy CT. Eur Radiol 2023; 33:1318-1328. [PMID: 36074261 DOI: 10.1007/s00330-022-09106-6] [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: 01/27/2022] [Revised: 07/13/2022] [Accepted: 08/10/2022] [Indexed: 02/03/2023]
Abstract
OBJECTIVES To assess the impact of dual-energy CT (DECT) utilization in practice by measuring the readers' confidence, the need for additional image requests, and diagnostic performance in renal lesion assessment, compared to single-energy CT (SECT) using contrast-enhanced MRI to establish the reference standard. MATERIALS AND METHODS Sixty-nine patients (M/F = 47/22) who underwent a dual-phase renal SECT (n = 34) or DECT (n = 35) and had a contrast-enhanced MRI within 180 days were retrospectively collected. Three radiologists assessed images on different sessions (SECT, DECT, and MRI) for (1) likely diagnosis (enhancing/non-enhancing); (2) diagnostic confidence (5-point Likert scale); (3) need for additional imaging test (yes/no); and (4) need for follow-up imaging (yes/no). Diagnostic accuracy was compared using AUC; p value < 0.05 was considered significant. RESULTS One hundred fifty-six lesions consisting of 18% enhancing (n = 28/156, mean size: 30.37 mm, range: 9.9-94 mm) and 82% non-enhancing (n = 128/156, mean size: 23.91 mm, range: 5.0-94.2 mm) were included. The confidence level was significantly lower for SECT than their MRI (4.50 vs. 4.80, p value < 0.05) but not significantly different for DECT and the corresponding MRI (4.78 vs. 4.78, p > 0.05). There were significantly more requests for additional imaging in the SECT session than the corresponding MRI (20% vs. 4%), which was not significantly different between DECT and their MRI counterpart session (5.7% vs. 4.9%). Inter-reader agreement was almost perfect for DECT and MRI (kappa: 0.8-1) and substantial in SECT sessions (kappa: 0.6-0.8) with comparable diagnostic accuracy between SECT, DECT, and MRI (p value > 0.05). CONCLUSION Single-phase DECT allows confident and reproducible characterization of renal masses with fewer recommendation for additional and follow-up imaging tests than dual-phase SECT and a performance similar to MRI. KEY POINTS • DECT utilization leads to similar additional image requests to MRI (5.7% vs. 4.9%, p value > 0.05), whereas single-energy CT utilization leads to significantly higher image requests (20% vs. 4%, p value < 0.05). • DECT and MRI utilization bring highly reproducible results with almost perfect inter-reader agreement (kappa: 0.8-1), better than the inter-reader agreement in SECT utilization (kappa: 0.6-0.8). • Readers' confidence was not significantly altered between DECT and their MRI readout session (p value > 0.05). In contrast, confidence in the diagnosis was significantly lower in the SECT session than their MRI readout (p value < 0.05).
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Affiliation(s)
- Ali Pourvaziri
- Department of Radiology, Massachusetts General Hospital, 55 Fruit St, White 270, Boston, MA, 02114, USA.
| | - Amirkasra Mojtahed
- Department of Radiology, Massachusetts General Hospital, 55 Fruit St, White 270, Boston, MA, 02114, USA
| | - Peter F Hahn
- Department of Radiology, Massachusetts General Hospital, 55 Fruit St, White 270, Boston, MA, 02114, USA
| | - Michael S Gee
- Department of Radiology, Massachusetts General Hospital, 55 Fruit St, White 270, Boston, MA, 02114, USA
| | - Avinash Kambadakone
- Department of Radiology, Massachusetts General Hospital, 55 Fruit St, White 270, Boston, MA, 02114, USA
| | - Dushyant V Sahani
- Department of Radiology, University of Washington, Seattle, WA, 98195, USA
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Bosniak Classification Version 2019: A CT-Based Update for Radiologists. CURRENT RADIOLOGY REPORTS 2022. [DOI: 10.1007/s40134-022-00397-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Odedra D, Narayanasamy S, Sabongui S, Priya S, Krishna S, Sheikh A. Dual Energy CT Physics-A Primer for the Emergency Radiologist. FRONTIERS IN RADIOLOGY 2022; 2:820430. [PMID: 37492677 PMCID: PMC10364985 DOI: 10.3389/fradi.2022.820430] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Accepted: 01/17/2022] [Indexed: 07/27/2023]
Abstract
Dual energy CT (DECT) refers to the acquisition of CT images at two energy spectra and can provide information about tissue composition beyond that obtainable by conventional CT. The attenuation of a photon beam varies depends on the atomic number and density of the attenuating material and the energy of the incoming photon beam. This differential attenuation of the beam at varying energy levels forms the basis of DECT imaging and enables separation of materials with different atomic numbers but similar CT attenuation. DECT can be used to detect and quantify materials like iodine, calcium, or uric acid. Several post-processing techniques are available to generate virtual non-contrast images, iodine maps, virtual mono-chromatic images, Mixed or weighted images and material specific images. Although initially the concept of dual energy CT was introduced in 1970, it is only over the past two decades that it has been extensively used in clinical practice owing to advances in CT hardware and post-processing capabilities. There are numerous applications of DECT in Emergency radiology including stroke imaging to differentiate intracranial hemorrhage and contrast staining, diagnosis of pulmonary embolism, characterization of incidentally detected renal and adrenal lesions, to reduce beam and metal hardening artifacts, in identification of uric acid renal stones and in the diagnosis of gout. This review article aims to provide the emergency radiologist with an overview of the physics and basic principles of dual energy CT. In addition, we discuss the types of DECT acquisition and post processing techniques including newer advances such as photon-counting CT followed by a brief discussion on the applications of DECT in Emergency radiology.
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Affiliation(s)
- Devang Odedra
- Department of Radiology, University of Toronto, Toronto, ON, Canada
| | - Sabarish Narayanasamy
- Department of Radiology, Carver College of Medicine, The University of Iowa, Iowa City, IA, United States
| | - Sandra Sabongui
- Keenan Research Centre for Biomedical Science, St Michael's Hospital, Toronto, ON, Canada
| | - Sarv Priya
- Department of Radiology, Carver College of Medicine, The University of Iowa, Iowa City, IA, United States
| | - Satheesh Krishna
- Department of Medical Imaging, Mount Sinai Hospital, and Women's College Hospital, University Health Network, University of Toronto, Toronto, ON, Canada
| | - Adnan Sheikh
- Department of Radiology, The University of British Columbia, Vancouver, BC, Canada
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Thiravit S, Brunnquell C, Cai LM, Flemon M, Mileto A. Use of dual-energy CT for renal mass assessment. Eur Radiol 2020; 31:3721-3733. [PMID: 33210200 DOI: 10.1007/s00330-020-07426-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Revised: 08/11/2020] [Accepted: 10/14/2020] [Indexed: 12/22/2022]
Abstract
Although dual-energy CT (DECT) may prove useful in a variety of abdominal imaging tasks, renal mass evaluation represents the area where this technology can be most impactful in abdominal imaging compared to routinely performed contrast-enhanced-only single-energy CT exams. DECT post-processing techniques, such as creation of virtual unenhanced and iodine density images, can help in the characterization of incidentally discovered renal masses that would otherwise remain indeterminate based on post-contrast imaging only. The purpose of this article is to review the use of DECT for renal mass assessment, including its benefits and existing limitations. KEY POINTS: • If DECT is selected as the scanning mode for most common abdominal protocols, many incidentally found renal masses can be fully triaged within the same exam. • Virtual unenhanced and iodine density DECT images can provide additional information when renal masses are discovered in the post-contrast-only setting. • For renal mass evaluation, virtual unenhanced and iodine density DECT images should be interpreted side-by-side to troubleshoot pitfalls that can potentially lead to erroneous interpretation.
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Affiliation(s)
- Shanigarn Thiravit
- Department of Radiology, University of Washington School of Medicine, 1959 NE Pacific Street, Box 357115, Seattle, WA, 98195, USA.,Division of Diagnostic Radiology, Department of Radiology, Faculty of Medicine, Siriraj Hospital, Mahidol University, Bangkok, Thailand
| | - Christina Brunnquell
- Department of Radiology, University of Washington School of Medicine, 1959 NE Pacific Street, Box 357115, Seattle, WA, 98195, USA
| | - Larry M Cai
- Department of Radiology, University of Washington School of Medicine, 1959 NE Pacific Street, Box 357115, Seattle, WA, 98195, USA
| | - Mena Flemon
- Department of Radiology, University of Washington School of Medicine, 1959 NE Pacific Street, Box 357115, Seattle, WA, 98195, USA
| | - Achille Mileto
- Department of Radiology, University of Washington School of Medicine, 1959 NE Pacific Street, Box 357115, Seattle, WA, 98195, USA.
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Wang ZJ, Nikolaidis P, Khatri G, Dogra VS, Ganeshan D, Goldfarb S, Gore JL, Gupta RT, Hartman RP, Heilbrun ME, Lyshchik A, Purysko AS, Savage SJ, Smith AD, Wolfman DJ, Wong-You-Cheong JJ, Lockhart ME. ACR Appropriateness Criteria® Indeterminate Renal Mass. J Am Coll Radiol 2020; 17:S415-S428. [PMID: 33153554 DOI: 10.1016/j.jacr.2020.09.010] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Accepted: 09/01/2020] [Indexed: 12/15/2022]
Abstract
Renal masses are increasingly detected in asymptomatic individuals as incidental findings. CT and MRI with intravenous contrast and a dedicated multiphase protocol are the mainstays of evaluation for indeterminate renal masses. A single-phase postcontrast dual-energy CT can be useful when a dedicated multiphase renal protocol CT is not available. Contrast-enhanced ultrasound with microbubble agents is a useful alternative for characterizing renal masses, especially for patients in whom iodinated CT contrast or gadolinium-based MRI contrast is contraindicated. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.
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Affiliation(s)
- Zhen J Wang
- University of California San Francisco School of Medicine, San Francisco, California.
| | | | - Gaurav Khatri
- Panel Vice-Chair, UT Southwestern Medical Center, Dallas, Texas
| | - Vikram S Dogra
- University of Rochester Medical Center, Rochester, New York
| | | | - Stanley Goldfarb
- University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania; American Society of Nephrology
| | - John L Gore
- University of Washington, Seattle, Washington; American Urological Association
| | - Rajan T Gupta
- Duke University Medical Center, Durham, North Carolina
| | | | | | - Andrej Lyshchik
- Thomas Jefferson University Hospital, Philadelphia, Pennsylvania
| | | | - Stephen J Savage
- Medical University of South Carolina, Charleston, South Carolina; American Urological Association
| | - Andrew D Smith
- University of Alabama at Birmingham, Birmingham, Alabama
| | - Darcy J Wolfman
- Johns Hopkins University School of Medicine, Washington, District of Columbia
| | | | - Mark E Lockhart
- Specialty Chair, University of Alabama at Birmingham, Birmingham, Alabama
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Chu JS, Wang ZJ. Protocol Optimization for Renal Mass Detection and Characterization. Radiol Clin North Am 2020; 58:851-873. [PMID: 32792119 DOI: 10.1016/j.rcl.2020.05.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Renal masses increasingly are found incidentally, largely due to the frequent use of medical imaging. Computed tomography (CT) and MR imaging are mainstays for renal mass characterization, presurgical planning of renal tumors, and surveillance after surgery or systemic therapy for advanced renal cell carcinomas. CT protocols should be tailored to different clinical indications, balancing diagnostic accuracy and radiation exposure. MR imaging protocols should take advantage of the improved soft tissue contrast for renal tumor diagnosis and staging. Optimized imaging protocols enable analysis of imaging features that help narrow the differential diagnoses and guide management in patients with renal masses.
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Affiliation(s)
- Jason S Chu
- Department of Radiology and Biomedical Imaging, University of California San Francisco, 505 Parnassus Avenue, Box 0628, San Francisco, CA 94143, USA
| | - Zhen J Wang
- Department of Radiology and Biomedical Imaging, University of California San Francisco, 505 Parnassus Avenue, Box 0628, San Francisco, CA 94143, USA.
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Obmann MM, Cosentino A, Cyriac J, Hofmann V, Stieltjes B, Boll DT, Yeh BM, Benz MR. Quantitative enhancement thresholds and machine learning algorithms for the evaluation of renal lesions using single-phase split-filter dual-energy CT. Abdom Radiol (NY) 2020; 45:1922-1928. [PMID: 31451887 DOI: 10.1007/s00261-019-02195-w] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
PURPOSE To establish thresholds for contrast enhancement-based attenuation (CM) and iodine concentration (IOD) for the quantitative evaluation of enhancement in renal lesions on single-phase split-filter dual-energy CT (tbDECT) and combine measurements in a machine learning algorithm to potentially improve performance. MATERIAL 126 patients with incidental renal cysts (both hypo- and hyperdense cysts) or high suspicion for renal cell carcinoma (312 total lesions) undergoing abdominal, portal venous phase tbDECT were initially included in this retrospective study. Gold standard was pathological confirmation or follow-up imaging (MRI or multiphasic CT). CM, IOD, and ROI size were recorded. Thresholds for CM and IOD were identified using Youden-Index of the empirical ROC curves. Decision tree (DTC) and random forest classifier (RFC) were trained. Sensitivities, specificities, and AUCs were compared using McNemar and DeLong test. RESULTS The final study cohort comprised 40 enhancing and 113 non-enhancing renal lesions. Optimal thresholds for quantitative iodine measurements and contrast enhancement-based attenuation were 1.0 ± 0.0 mg/ml and 23.6 ± 0.3 HU, respectively. Single DECT parameters (IOD, CM) showed similar overall performance with an AUC of 0.894 and 0.858 (p = 0.541) (sensitivity 90 and 80%, specificity 88 and 92%, respectively). While overall performance for the DTC (AUC 0.944) was higher than RFC (AUC 0.886), this difference (p = 0.409) and comparison to CM (p = 0.243) and IOD (p = 0.353) was not statistically significant. CONCLUSIONS Enhancement in incidental renal lesions on single-phase tbDECT can be classified with up to 87.5% sensitivity and 94.6% specificity. Algorithms combining DECT parameters did not increase overall performance.
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Affiliation(s)
- Markus M Obmann
- Clinic of Radiology and Nuclear Medicine, University Hospital Basel, University of Basel, Petersgraben 4, 4031, Basel, Switzerland.
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, San Francisco, CA, USA.
| | - Aurelio Cosentino
- Department of Surgical Sciences, Radiology Unit, University of Turin, Turin, Italy
| | - Joshy Cyriac
- Clinic of Radiology and Nuclear Medicine, University Hospital Basel, University of Basel, Petersgraben 4, 4031, Basel, Switzerland
| | - Verena Hofmann
- Clinic of Radiology and Nuclear Medicine, University Hospital Basel, University of Basel, Petersgraben 4, 4031, Basel, Switzerland
| | - Bram Stieltjes
- Clinic of Radiology and Nuclear Medicine, University Hospital Basel, University of Basel, Petersgraben 4, 4031, Basel, Switzerland
| | - Daniel T Boll
- Clinic of Radiology and Nuclear Medicine, University Hospital Basel, University of Basel, Petersgraben 4, 4031, Basel, Switzerland
| | - Benjamin M Yeh
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, San Francisco, CA, USA
| | - Matthias R Benz
- Clinic of Radiology and Nuclear Medicine, University Hospital Basel, University of Basel, Petersgraben 4, 4031, Basel, Switzerland.
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Krishna S, Leckie A, Kielar A, Hartman R, Khandelwal A. Imaging of Renal Cancer. Semin Ultrasound CT MR 2020; 41:152-169. [DOI: 10.1053/j.sult.2019.12.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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10
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Prince JT. Comparison of Diagnostic Medical Sonography, Computed Tomography, Magnetic Resonance Imaging, and Contrast-Enhanced Ultrasound in the Investigation of Renal Lesions. JOURNAL OF DIAGNOSTIC MEDICAL SONOGRAPHY 2020. [DOI: 10.1177/8756479319882015] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
This review explores the classification and evaluation of suspicious renal lesions across several radiologic imaging modalities. Diagnostic medical sonography (DMS), computed tomography (CT), magnetic resonance imaging (MRI), and contrast-enhanced ultrasound (CEUS) are the primary modalities used to investigate questionable lesions found within the kidneys. Renal masses may range from completely benign to malignant. They are classified based on many different features and characteristics. These lesions may be simple cystic, complex cystic, or solid in nature. Masses may also exhibit varying degrees of vascularity, septations, and calcifications. The discussed imaging modalities have varying strengths, limitations, and implications for use. Imaging techniques may be used independently or in conjunction to best diagnose and treat a patient with a suspicious renal mass. The aim of this review was to describe the diagnostic value of the imaging modalities (DMS, CT, MRI, and CEUS) and their role in the evaluation of suspicious renal lesions.
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Si-Mohamed S, Dupuis N, Tatard-Leitman V, Rotzinger D, Boccalini S, Dion M, Vlassenbroek A, Coulon P, Yagil Y, Shapira N, Douek P, Boussel L. Virtual versus true non-contrast dual-energy CT imaging for the diagnosis of aortic intramural hematoma. Eur Radiol 2019; 29:6762-6771. [PMID: 31264015 DOI: 10.1007/s00330-019-06322-5] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2019] [Revised: 05/24/2019] [Accepted: 06/11/2019] [Indexed: 12/23/2022]
Abstract
PURPOSE To assess whether virtual non-contrast (VNC) images derived from contrast dual-layer dual-energy computed tomography (DL-DECT) images could replace true non-contrast (TNC) images for aortic intramural hematoma (IMH) diagnosis in acute aortic syndrome (AAS) imaging protocols by performing quantitative as well as qualitative phantom and clinical studies. MATERIALS AND METHODS Patients with confirmed IMH were included retrospectively in two centers. For in vitro imaging, a custom-made phantom of IMH was placed in a semi-anthropomorphic thorax phantom (QRM GmbH) and imaged on a DL-DECT at 120 kVp under various conditions of patient size, radiation exposure, and reconstruction modes. For in vivo imaging, 21 patients (70 ± 13 years) who underwent AAS imaging protocols at 120 kVp were included. In both studies, contrast-to-noise ratio (CNR) between hematoma and lumen was compared using a paired t test. Diagnostic confidence (1 = non-diagnostic, 4 = exemplary) for VNC and TNC images was rated by two radiologists and compared. Effective radiation doses for each acquisition were calculated. RESULTS In both the phantom and clinical studies, we observed that the CNRs were similar between the VNC and TNC images. Moreover, both methods allowed differentiating the hyper-attenuation within the hematoma from the blood. Finally, we obtained equivalent high diagnostic confidence with both VNC and TNC images (VNC = 3.2 ± 0.7, TNC = 3.1 ± 0.7; p = 0.3). Finally, by suppressing TNC acquisition and using VNC, the mean effective dose reduction would be 40%. CONCLUSION DL-DECT offers similar performances with VNC and TNC images for IMH diagnosis without compromise in diagnostic image quality. KEY POINTS • Dual-layer dual-energy CT enables virtual non-contrast imaging from a contrast-enhanced acquisition. • Virtual non-contrast imaging with dual-layer dual-energy CT reduces the number of acquisitions and radiation exposure in acute aortic syndrome imaging protocol. • Dual-layer dual-energy CT has the potential to become a suitable imaging tool for acute aortic syndrome.
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Affiliation(s)
- Salim Si-Mohamed
- Univ Lyon, INSA-Lyon, Université Claude Bernard Lyon 1, UJM-Saint Etienne, CNRS, Inserm, CREATIS UMR 5220, U1206, F-69621, Lyon, France.
- Radiology Department, Hospices Civils de Lyon, CHU Louis Pradel, 59 Boulevard Pinel, 69500, Bron, France.
| | - Nicolas Dupuis
- Univ Lyon, INSA-Lyon, Université Claude Bernard Lyon 1, UJM-Saint Etienne, CNRS, Inserm, CREATIS UMR 5220, U1206, F-69621, Lyon, France
- Radiology Department, Hospices Civils de Lyon, CHU Louis Pradel, 59 Boulevard Pinel, 69500, Bron, France
- Anatomy Lab, Rockefeller Faculty, Lyon Est, Lyon, France
| | - Valérie Tatard-Leitman
- Univ Lyon, INSA-Lyon, Université Claude Bernard Lyon 1, UJM-Saint Etienne, CNRS, Inserm, CREATIS UMR 5220, U1206, F-69621, Lyon, France
| | - David Rotzinger
- Department of Diagnostic and Interventional Radiology, Lausanne University Hospital , Lausanne, Switzerland
| | - Sara Boccalini
- Radiology Department, Hospices Civils de Lyon, CHU Louis Pradel, 59 Boulevard Pinel, 69500, Bron, France
| | - Matthias Dion
- Univ Lyon, INSA-Lyon, Université Claude Bernard Lyon 1, UJM-Saint Etienne, CNRS, Inserm, CREATIS UMR 5220, U1206, F-69621, Lyon, France
- Radiology Department, Hospices Civils de Lyon, CHU Louis Pradel, 59 Boulevard Pinel, 69500, Bron, France
- Anatomy Lab, Rockefeller Faculty, Lyon Est, Lyon, France
| | | | | | - Yoad Yagil
- Global Advanced Technologies, CT, Philips, Haifa, Israel
| | - Nadav Shapira
- Global Advanced Technologies, CT, Philips, Haifa, Israel
| | - Philippe Douek
- Univ Lyon, INSA-Lyon, Université Claude Bernard Lyon 1, UJM-Saint Etienne, CNRS, Inserm, CREATIS UMR 5220, U1206, F-69621, Lyon, France
- Radiology Department, Hospices Civils de Lyon, CHU Louis Pradel, 59 Boulevard Pinel, 69500, Bron, France
| | - Loic Boussel
- Univ Lyon, INSA-Lyon, Université Claude Bernard Lyon 1, UJM-Saint Etienne, CNRS, Inserm, CREATIS UMR 5220, U1206, F-69621, Lyon, France
- Radiology Department, Hospices Civils de Lyon, CHU Louis Pradel, 59 Boulevard Pinel, 69500, Bron, France
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Pourvaziri A, Parakh A, Mojtahed A, Kambadakone A, Sahani DV. Diagnostic performance of dual-energy CT and subtraction CT for renal lesion detection and characterization. Eur Radiol 2019; 29:6559-6570. [DOI: 10.1007/s00330-019-06224-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Revised: 03/21/2019] [Accepted: 04/04/2019] [Indexed: 01/14/2023]
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Kessner R, Große Hokamp N, Ciancibello L, Ramaiya N, Herrmann KA. Renal cystic lesions characterization using spectral detector CT (SDCT): Added value of spectral results. Br J Radiol 2019; 92:20180915. [PMID: 31124701 DOI: 10.1259/bjr.20180915] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
OBJECTIVES To evaluate the added value of spectral results derived from Spectral Detector CT (SDCT) to the characterization of renal cystic lesions (RCL). METHODS This retrospective study was approved by the local Institutional review board. 70 consecutive patients who underwent abdominopelvic SDCT and had at least one RCL were included. 84 RCL were categorized as simple, complex or neoplastic based on attenuation values on single-phase post-contrast images. Attenuation values were measured in each lesion on standard conventional CT images (stCI) and virtual monoenergetic images of 40keV and 100keV. A spectral curve slope was calculated and intra lesional iodine concentration (IC) was measured using iodine-density maps. Reference standard was established using histopathologic correlation, prior and follow-up imaging. Analysis of variance (ANOVA) was used to compare between the groups. RESULTS Mean attenuation values for benign simple and complex RCL differed significantly (42 ± 16 vs 8 ± 3 HU; p < 0.001). IC was almost identical in benign simple and complex RCL (0.23 ± 0.04 mg ml-1 vs 0.24 ± 0.04 mg ml-1), while IC in neoplastic RCL was significantly higher (2.10 ± 0.08 mg ml-1 ; p < 0.001). The mean spectral curve slope did not differ significantly between simple and complex RCL (0.30 ± 0.03 vs 0.33 ± 0.05) but was significantly higher in neoplastic RCL (2.60 ± 0.10; p < 0.001). CONCLUSIONS Spectral results of SDCT are highly promising in distinguishing benign complex RCL from enhancing neoplastic RCL based on single-phase post-contrast imaging only. ADVANCES IN KNOWLEDGE SDCT can assist in differentiating between benign complex and neoplastic renal cystic lesions.
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Affiliation(s)
- Rivka Kessner
- 1 Department of Radiology, University Hospitals Cleveland Medical Center and Case Western Reserve University, Cleveland, Ohio, USA.,2 Department of Diagnostic Imaging, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Nils Große Hokamp
- 1 Department of Radiology, University Hospitals Cleveland Medical Center and Case Western Reserve University, Cleveland, Ohio, USA.,3 University Hospital Cologne, Institute for Diagnostic and Interventional Radiology, Cologne, Germany
| | - Les Ciancibello
- 1 Department of Radiology, University Hospitals Cleveland Medical Center and Case Western Reserve University, Cleveland, Ohio, USA
| | - Nikhil Ramaiya
- 1 Department of Radiology, University Hospitals Cleveland Medical Center and Case Western Reserve University, Cleveland, Ohio, USA
| | - Karin A Herrmann
- 1 Department of Radiology, University Hospitals Cleveland Medical Center and Case Western Reserve University, Cleveland, Ohio, USA
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Meyer M, Nelson RC, Vernuccio F, González F, Farjat AE, Patel BN, Samei E, Henzler T, Schoenberg SO, Marin D. Virtual Unenhanced Images at Dual-Energy CT: Influence on Renal Lesion Characterization. Radiology 2019; 291:381-390. [DOI: 10.1148/radiol.2019181100] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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Systematic Review and Meta-Analysis Investigating the Diagnostic Yield of Dual-Energy CT for Renal Mass Assessment. AJR Am J Roentgenol 2019; 212:1044-1053. [PMID: 30835518 DOI: 10.2214/ajr.18.20625] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
OBJECTIVE. The objective of our study was to perform a systematic review and meta-analysis to evaluate the diagnostic accuracy of dual-energy CT (DECT) for renal mass evaluation. MATERIALS AND METHODS. In March 2018, we searched MEDLINE, Cochrane Database of Systematic Reviews, Embase, and Web of Science databases. Analytic methods were based on Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). Pooled estimates for sensitivity, specificity, and diagnostic odds ratios were calculated for DECT-based virtual monochromatic imaging (VMI) and iodine quantification techniques as well as for conventional attenuation measurements from renal mass CT protocols. I2 was used to evaluate heterogeneity. The methodologic quality of the included studies and potential bias were assessed using items from the Quality Assessment Tool for Diagnostic Accuracy Studies 2 (QUADAS-2). RESULTS. Of the 1043 articles initially identified, 13 were selected for inclusion (969 patients, 1193 renal masses). Cumulative data of sensitivity, specificity, and summary diagnostic odds ratio for VMI were 87% (95% CI, 80-92%; I2, 92.0%), 93% (95% CI, 90-96%; I2, 18.0%), and 183.4 (95% CI, 30.7-1093.4; I2, 61.6%), respectively. Cumulative data of sensitivity, specificity, and summary diagnostic odds ratio for iodine quantification were 99% (95% CI, 97-100%; I2, 17.6%), 91% (95% CI, 89-94%; I2, 84.2%), and 511.5 (95% CI, 217-1201; I2, 0%). No significant differences in AUCs were found when comparing iodine quantification to conventional attenuation measurements (p = 0.79). CONCLUSION. DECT yields high accuracy for renal mass evaluation. Determination of iodine content with the iodine quantification technique shows diagnostic accuracy similar to conventional attenuation measurements from renal mass CT protocols. The iodine quantification technique may be used to characterize incidental renal masses when a dedicated renal mass protocol is not available.
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Comparison of Iodine Quantification and Conventional Attenuation Measurements for Differentiating Small, Truly Enhancing Renal Masses From High-Attenuation Nonenhancing Renal Lesions With Dual-Energy CT. AJR Am J Roentgenol 2019; 213:W26-W37. [PMID: 30917024 DOI: 10.2214/ajr.18.20547] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
OBJECTIVE. The purpose of this study is to determine whether iodine quantification techniques from contrast-enhanced dual-energy CT (DECT) data allow equal differentiation of small enhancing renal masses from high-attenuation (> 20 HU of unenhanced attenuation) nonenhancing lesions, compared with conventional attenuation measurements. MATERIALS AND METHODS. A total of 220 nonconsecutive patients (mean [± SD] age, 66 ± 13 years; 130 men and 90 women) with 265 high-attenuation renal lesions (mean attenuation, 54 ± 33 HU; 91 enhancing lesions) were included. Each patient underwent single-energy unenhanced CT followed by DECT during the nephrographic phase using one of four different high-end DECT platforms (first- and second-generation rapid-kilovoltage-switching DECT platforms and second- and third-generation dual-source DECT platforms). Iodine quantification measurements and conventional attenuation change measurements were calculated for each lesion. Diagnostic accuracy was determined by pathologic analysis, confirmation with another imaging modality, or greater than 24 months of imaging follow-up as the reference standard. RESULTS. The diagnostic accuracy for differentiating enhancing from nonenhancing renal lesions was significantly higher for conventional attenuation change measurements, compared with iodine quantification measurements (AUC values, 0.973 vs 0.875; p < 0.0001). The diagnostic performance of iodine quantification measurements improved only marginally with the utilization of DECT platform-specific optimized iodine quantification thresholds, yielding AUC values of 0.907 and 0.893 for the rapid-kilovoltage-switching DECT and dual-source DECT platforms, respectively. Unenhanced lesion attenuation (p = 0.0010) and intraparenchymal location (p = 0.0249) significantly influenced the diagnostic accuracy of the iodine quantification techniques. CONCLUSION. Iodine quantification from DECT data yields inferior diagnostic accuracy when compared with conventional attenuation change measurements for differentiating small, truly enhancing renal masses and high-attenuation renal lesions.
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Morgan DE. The Role of Dual-Energy Computed Tomography in Assessment of Abdominal Oncology and Beyond. Radiol Clin North Am 2018; 56:565-585. [PMID: 29936948 DOI: 10.1016/j.rcl.2018.03.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
The added value and strength of dual energy computed tomography for the evaluation of oncologic patients revolve around the use of lower energy reconstructed images and iodine material density images. Lower keV simulated monoenergetic images optimize soft tissue tumor to nontumoral attenuation differences and increase contrast to noise ratios to improve lesion detection. Iodine material density images or maps are helpful from a qualitative standpoint for image interpretation because they result in improved detection and characterization of tumors and lymph node involvement, and from a quantitative assessment by enabling interrogation of specific properties of tissues to predict and assess therapeutic response.
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Affiliation(s)
- Desiree E Morgan
- Department of Radiology University of Alabama at Birmingham, 619 19th Street South, JTN 456, Birmingham, AL 35249-6830, USA.
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Prevalence of Solid Tumors in Incidentally Detected Homogeneous Renal Masses Measuring > 20 HU on Portal Venous Phase CT. AJR Am J Roentgenol 2018; 211:W173-W177. [PMID: 29995501 DOI: 10.2214/ajr.17.19351] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
OBJECTIVE The purpose of this study was to determine the prevalence of solid tumors in incidental homogeneous renal masses with attenuation greater than 20 HU on portal venous phase CT images. MATERIALS AND METHODS In this retrospective study, the records of patients with incidental indeterminate (> 20 HU) homogeneous renal masses on portal venous phase CT scans from September 11, 2007, through March 18, 2017, were identified. Adult patients were included if they had undergone follow-up ultrasound, contrast-enhanced MRI, multiphase contrast-enhanced CT, or pathologic analysis alone to confirm the solid or cystic nature of the lesion. A single ROI was placed in the center of the mass, and lesions were characterized as ≥ 50% exophytic, < 50% exophytic, or entirely surrounded by renal parenchyma. RESULTS There were 322 masses in 267 patients. The mean lesion size was 16.6 (SD, 9.8) mm (range, 9-45 mm). Lesions were ≥ 50% exophytic in 92 cases, < 50% exophytic in 111 cases, and completely surrounded by renal parenchyma in 119 cases. All nonsolid lesions were characterized as benign cysts. The numbers of solid lesions per total number of lesions in each attenuation group were: 20-30 HU (0/140), 30-40 HU (0/67), 40-50 HU (1/38), 50-60 HU (3/24), 60-70 HU (5/17), 70-80 HU (5/17), and > 80 HU (8/19). All 207 lesions in the 20- to 40-HU range were benign cysts with no solid lesions (0%; 95% CI, 0.0-1.4%). CONCLUSION Small homogeneous renal masses measuring 20-40 HU on portal venous phase CT images are highly likely to be benign cysts.
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Abstract
Small renal masses are increasingly detected incidentally at imaging. They vary widely in histology and aggressiveness, and include benign renal tumors and renal cell carcinomas that can be either indolent or aggressive. Imaging plays a key role in the characterization of these small renal masses. While a confident diagnosis can be made in many cases, some renal masses are indeterminate at imaging and can present as diagnostic dilemmas for both the radiologists and the referring clinicians. This article will summarize the current evidence of imaging features that correlate with the biology of small solid renal masses, and discuss key approaches in imaging characterization of these masses using CT and MRI.
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Affiliation(s)
- Zhen J Wang
- 1 Department of Radiology and Biomedical Imaging, University of California San Francisco , San Francisco, CA , USA
| | - Antonio C Westphalen
- 1 Department of Radiology and Biomedical Imaging, University of California San Francisco , San Francisco, CA , USA
| | - Ronald J Zagoria
- 1 Department of Radiology and Biomedical Imaging, University of California San Francisco , San Francisco, CA , USA
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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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Krishna S, Murray CA, McInnes MD, Chatelain R, Siddaiah M, Al-Dandan O, Narayanasamy S, Schieda N. CT imaging of solid renal masses: pitfalls and solutions. Clin Radiol 2017; 72:708-721. [PMID: 28592361 DOI: 10.1016/j.crad.2017.05.003] [Citation(s) in RCA: 58] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2016] [Revised: 04/20/2017] [Accepted: 05/02/2017] [Indexed: 12/22/2022]
Abstract
Computed tomography (CT) remains the first-line imaging test for the characterisation of renal masses; however, CT has inherent limitations, which if unrecognised, may result in errors. The purpose of this manuscript is to present 10 pitfalls in the CT evaluation of solid renal masses. Thin section non-contrast enhanced CT (NECT) is required to confirm the presence of macroscopic fat and diagnosis of angiomyolipoma (AML). Renal cell carcinoma (RCC) can mimic renal cysts at NECT when measuring <20 HU, but are usually heterogeneous with irregular margins. Haemorrhagic cysts (HC) may simulate solid lesions at NECT; however, a homogeneous lesion measuring >70 HU is essentially diagnostic of HC. Homogeneous lesions measuring 20-70 HU at NECT or >20 HU at contrast-enhanced (CE) CT, are indeterminate, requiring further evaluation. Dual-energy CT (DECT) can accurately characterise these lesions at baseline through virtual NECT, iodine overlay images, or quantitative iodine concentration analysis without recalling the patient. A minority of hypo-enhancing renal masses (most commonly papillary RCC) show indeterminate or absent enhancement at multiphase CT. Follow-up, CE ultrasound or magnetic resonance imaging (MRI) is required to further characterise these lesions. Small (<3 cm) endophytic cysts commonly show pseudo-enhancement, which may simulate RCC; this can be overcome with DECT or MRI. In small (<4 cm) solid renal masses, 20% of lesions are benign, chiefly AML without visible fat or oncocytoma. Low-dose techniques may simulate lesion heterogeneity due to increased image noise, which can be ameliorated through the appropriate use of iterative reconstruction algorithms.
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Affiliation(s)
- S Krishna
- Department of Medical Imaging, The Ottawa Hospital, University of Ottawa, Ottawa, Canada
| | - C A Murray
- Department of Medical Imaging, The Ottawa Hospital, University of Ottawa, Ottawa, Canada
| | - M D McInnes
- Department of Medical Imaging, The Ottawa Hospital, University of Ottawa, Ottawa, Canada
| | - R Chatelain
- Department of Medical Imaging, The Ottawa Hospital, University of Ottawa, Ottawa, Canada
| | - M Siddaiah
- Department of Medical Imaging, The Ottawa Hospital, University of Ottawa, Ottawa, Canada
| | - O Al-Dandan
- Department of Radiology, University of Dammam, Dammam, Saudi Arabia
| | - S Narayanasamy
- Department of Medical Imaging, The Ottawa Hospital, University of Ottawa, Ottawa, Canada
| | - N Schieda
- Department of Medical Imaging, The Ottawa Hospital, University of Ottawa, Ottawa, Canada.
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