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Becker J, Feitelson LM, Risch F, Canalini L, Kaufmann D, Wudy R, Jehs B, Haerting M, Wollny C, Scheurig-Muenkler C, Kroencke T, Schwarz F, Decker JA, Bette S. Spectral Differentiation of Hyperdense Non-Vascular and Vascular Renal Lesions Without Solid Components in Contrast-Enhanced Photon-Counting Detector CT Scans-A Pilot Study. Diagnostics (Basel) 2025; 15:79. [PMID: 39795607 PMCID: PMC11719968 DOI: 10.3390/diagnostics15010079] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2024] [Revised: 12/18/2024] [Accepted: 12/27/2024] [Indexed: 01/13/2025] Open
Abstract
Introduction: The number of incidental renal lesions identified in CT scans of the abdomen is increasing. Objective: The aim of this study was to determine whether hyperdense renal lesions without solid components in a portal venous CT scan can be clearly classified as vascular or non-vascular by material decomposition into iodine and water. Methods: This retrospective single-center study included 26 patients (mean age 72 years ± 9; 16 male) with 42 hyperdense renal lesions (>20 HU) in a contrast-enhanced Photon-Counting Detector CT scan (PCD-CT) between May and December 2022. Spectral decomposition into virtual non-contrast (VNC) images and iodine quantification maps was performed, and HU values were quantified within the lesions. Further imaging and histopathological reports served as reference standards. Results: Mean VNC values were 55.7 (±24.2) HU for non-vascular and 32.2 (±11.1) HU for vascular renal lesions. Mean values in the iodine maps were 5.7 (±7.8) HU for non-vascular and 33.3 (±19.0) HU for vascular renal lesions. Using a threshold of >20.3 HU in iodine maps, a total of 7/8 (87.5%) vascular lesions were correctly identified. Conclusion: This proof-of-principle study suggests that the routine use of spectral information acquired in PCD-CT scans might be able to reduce the necessary workup for hyperdense renal lesions without solid components. Further studies with larger patient cohorts are necessary to validate the results of this study and to determine the usefulness of this method in clinical routine.
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Affiliation(s)
- Judith Becker
- Clinic for Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Augsburg, Stenglinstr. 2, 86156 Augsburg, Germany; (J.B.); (L.-M.F.); (F.R.); (L.C.); (D.K.); (R.W.); (B.J.); (M.H.); (C.W.); (C.S.-M.); (J.A.D.); (S.B.)
| | - Laura-Marie Feitelson
- Clinic for Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Augsburg, Stenglinstr. 2, 86156 Augsburg, Germany; (J.B.); (L.-M.F.); (F.R.); (L.C.); (D.K.); (R.W.); (B.J.); (M.H.); (C.W.); (C.S.-M.); (J.A.D.); (S.B.)
| | - Franka Risch
- Clinic for Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Augsburg, Stenglinstr. 2, 86156 Augsburg, Germany; (J.B.); (L.-M.F.); (F.R.); (L.C.); (D.K.); (R.W.); (B.J.); (M.H.); (C.W.); (C.S.-M.); (J.A.D.); (S.B.)
| | - Luca Canalini
- Clinic for Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Augsburg, Stenglinstr. 2, 86156 Augsburg, Germany; (J.B.); (L.-M.F.); (F.R.); (L.C.); (D.K.); (R.W.); (B.J.); (M.H.); (C.W.); (C.S.-M.); (J.A.D.); (S.B.)
| | - David Kaufmann
- Clinic for Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Augsburg, Stenglinstr. 2, 86156 Augsburg, Germany; (J.B.); (L.-M.F.); (F.R.); (L.C.); (D.K.); (R.W.); (B.J.); (M.H.); (C.W.); (C.S.-M.); (J.A.D.); (S.B.)
| | - Ramona Wudy
- Clinic for Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Augsburg, Stenglinstr. 2, 86156 Augsburg, Germany; (J.B.); (L.-M.F.); (F.R.); (L.C.); (D.K.); (R.W.); (B.J.); (M.H.); (C.W.); (C.S.-M.); (J.A.D.); (S.B.)
| | - Bertram Jehs
- Clinic for Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Augsburg, Stenglinstr. 2, 86156 Augsburg, Germany; (J.B.); (L.-M.F.); (F.R.); (L.C.); (D.K.); (R.W.); (B.J.); (M.H.); (C.W.); (C.S.-M.); (J.A.D.); (S.B.)
| | - Mark Haerting
- Clinic for Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Augsburg, Stenglinstr. 2, 86156 Augsburg, Germany; (J.B.); (L.-M.F.); (F.R.); (L.C.); (D.K.); (R.W.); (B.J.); (M.H.); (C.W.); (C.S.-M.); (J.A.D.); (S.B.)
| | - Claudia Wollny
- Clinic for Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Augsburg, Stenglinstr. 2, 86156 Augsburg, Germany; (J.B.); (L.-M.F.); (F.R.); (L.C.); (D.K.); (R.W.); (B.J.); (M.H.); (C.W.); (C.S.-M.); (J.A.D.); (S.B.)
| | - Christian Scheurig-Muenkler
- Clinic for Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Augsburg, Stenglinstr. 2, 86156 Augsburg, Germany; (J.B.); (L.-M.F.); (F.R.); (L.C.); (D.K.); (R.W.); (B.J.); (M.H.); (C.W.); (C.S.-M.); (J.A.D.); (S.B.)
| | - Thomas Kroencke
- Clinic for Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Augsburg, Stenglinstr. 2, 86156 Augsburg, Germany; (J.B.); (L.-M.F.); (F.R.); (L.C.); (D.K.); (R.W.); (B.J.); (M.H.); (C.W.); (C.S.-M.); (J.A.D.); (S.B.)
- Centre for Advanced Analytics and Predictive Sciences (CAAPS), University of Augsburg, Universitätsstr. 2, 86159 Augsburg, Germany
| | - Florian Schwarz
- Centre for Diagnostic Imaging and Interventional Therapy, Donau-Isar-Klinikum, Perlasberger Straße 41, 94469 Deggendorf, Germany;
| | - Josua A. Decker
- Clinic for Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Augsburg, Stenglinstr. 2, 86156 Augsburg, Germany; (J.B.); (L.-M.F.); (F.R.); (L.C.); (D.K.); (R.W.); (B.J.); (M.H.); (C.W.); (C.S.-M.); (J.A.D.); (S.B.)
| | - Stefanie Bette
- Clinic for Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Augsburg, Stenglinstr. 2, 86156 Augsburg, Germany; (J.B.); (L.-M.F.); (F.R.); (L.C.); (D.K.); (R.W.); (B.J.); (M.H.); (C.W.); (C.S.-M.); (J.A.D.); (S.B.)
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Virarkar MK, Mileto A, Vulasala SSR, Ananthakrishnan L, Bhosale P. Dual-Energy Computed Tomography Applications in the Genitourinary Tract. Radiol Clin North Am 2023; 61:1051-1068. [PMID: 37758356 DOI: 10.1016/j.rcl.2023.05.007] [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] [Indexed: 10/03/2023]
Abstract
By virtue of material differentiation capabilities afforded through dedicated postprocessing algorithms, dual-energy CT (DECT) has been shown to provide benefit in the evaluation of various diseases. In this article, we review the diagnostic use of DECT in the assessment of genitourinary diseases, with emphasis on its role in renal stone characterization, incidental renal and adrenal lesion characterization, retroperitoneal trauma, reduction of radiation, and contrast dose and cost-effectiveness potential. We also discuss future perspectives of the DECT scanning mode, including the use of novel contrast injection strategies and photon-counting detector computed tomography.
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Affiliation(s)
- Mayur K Virarkar
- Department of Radiology, University of Florida College of Medicine, Clinical Center, C90, 2nd Floor, 655 West 8th Street, Jacksonville, FL 32209, USA
| | - Achille Mileto
- Department of Radiology, Mayo Clinic, Mayo Building West, 2nd Floor, 200 First Street SW, Rochester, MN, 55905, USA
| | - Sai Swarupa R Vulasala
- Department of radiology, University of Florida College of Medicine, Clinical Center, C90, 2nd Floor, 655 West 8th Street, Jacksonville, FL, 32209, USA.
| | - Lakshmi Ananthakrishnan
- Department of Radiology, UT Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA
| | - Priya Bhosale
- Department of Diagnostic Radiology, Division of Diagnostic Imaging, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Boulevard, Unit 1479, Houston, TX 77030, USA
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Schade KA, Mergen V, Sartoretti T, Alkadhi H, Euler A. Pseudoenhancement in Cystic Renal Lesions - Impact of Virtual Monoenergetic Images of Photon-Counting Detector CT on Lesion Classification. Acad Radiol 2023; 30 Suppl 1:S305-S313. [PMID: 37150736 DOI: 10.1016/j.acra.2023.04.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Revised: 03/30/2023] [Accepted: 04/03/2023] [Indexed: 05/09/2023]
Abstract
RATIONALE AND OBJECTIVES To investigate the impact of virtual monoenergetic images (VMI) from photon-counting detector CT (PCD-CT) on the enhancement and classification of renal cysts. MATERIALS AND METHODS Adults with renal cysts (≥7 mm) who received a triphasic examination on a clinical PCD-CT (120 kVp; IQ level 68) between July 2021 and March 2022 were retrospectively identified. Only non-enhancing cysts (enhancement<10 HU between unenhanced and venous phase at 70 keV) were included. VMI from 40 to 190 keV with increments of 10 keV were reconstructed from the venous phase. Enhancement was measured to classify each lesion as non-enhancing (<10 HU), equivocally enhancing (10-19 HU), and definitely enhancing (≥20 HU). Classification changes as a function of VMI were assessed. Pearson correlation coefficient, the Kruskal-Wallis and the Chi-square test were used. RESULTS A total of 86 patients (mean age, 74 ± 9 years; 74 male) with 160 non-enhancing renal cysts (17.6 ± 10 mm) were included. CT attenuation of the cysts increased from higher to lower VMI levels with a mean attenuation of 4 ± 11 HU at 190 keV to 36 ± 17 HU at 40 keV. Mean attenuation of the renal parenchyma was 43 ± 4 HU at 190 keV and 414 ± 71 HU at 40 keV. No cyst exhibited enhancement from 70 keV to 190 keV. At 40, 50, and 60 keV, 35% (56/160), 29% (47/160) and 9% (15/160) of cysts showed equivocal and 46% (74/160), 10% (16/160), and 0% (0/160) definite enhancement, respectively. There was no significant influence of size (P=.13), cyst location (P=.9) and BMI (P=.19) on enhancement classification. CONCLUSION VMI has a relevant impact on enhancement and classification of renal cysts with misclassification in a large number of cases at energy levels below 70 keV.
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Affiliation(s)
- Katharina Alexandra Schade
- Diagnostic and Interventional Radiology, University Hospital Zurich, University of Zurich, Zurich, Switzerland (K.A.S., V.M., T.S., H.A., A.E.)
| | - Victor Mergen
- Diagnostic and Interventional Radiology, University Hospital Zurich, University of Zurich, Zurich, Switzerland (K.A.S., V.M., T.S., H.A., A.E.)
| | - Thomas Sartoretti
- Diagnostic and Interventional Radiology, University Hospital Zurich, University of Zurich, Zurich, Switzerland (K.A.S., V.M., T.S., H.A., A.E.)
| | - Hatem Alkadhi
- Diagnostic and Interventional Radiology, University Hospital Zurich, University of Zurich, Zurich, Switzerland (K.A.S., V.M., T.S., H.A., A.E.)
| | - André Euler
- Diagnostic and Interventional Radiology, University Hospital Zurich, University of Zurich, Zurich, Switzerland (K.A.S., V.M., T.S., H.A., A.E.); Institute of Radiology, Kantonsspital Baden, Baden, Switzerland (A.E.).
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Agostini A, Borgheresi A, Mariotti F, Ottaviani L, Carotti M, Valenti M, Giovagnoni A. New Frontiers in Oncological Imaging With Computed Tomography: From Morphology to Function. Semin Ultrasound CT MR 2023; 44:214-227. [PMID: 37245886 DOI: 10.1053/j.sult.2023.03.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/03/2023]
Abstract
The latest evolutions in Computed Tomography (CT) technology have several applications in oncological imaging. The innovations in hardware and software allow for the optimization of the oncological protocol. Low-kV acquisitions are possible thanks to the new powerful tubes. Iterative reconstruction algorithms and artificial intelligence are helpful for the management of image noise during image reconstruction. Functional information is provided by spectral CT (dual-energy and photon counting CT) and perfusion CT.
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Affiliation(s)
- Andrea Agostini
- Department of Clinical, Special and Dental Sciences. University Politecnica delle Marche, Ancona, Italy; Department of Radiological Sciences, Division of Clinical Radiology, University Hospital "Azienda Ospedaliero Universitaria delle Marche", Ancona, Italy.
| | - Alessandra Borgheresi
- Department of Clinical, Special and Dental Sciences. University Politecnica delle Marche, Ancona, Italy; Department of Radiological Sciences, Division of Clinical Radiology, University Hospital "Azienda Ospedaliero Universitaria delle Marche", Ancona, Italy
| | - Francesco Mariotti
- Department of Radiological Sciences, Division of Medical Physics, University Hospital "Azienda Ospedaliero Universitaria delle Marche", Ancona, Italy
| | - Letizia Ottaviani
- Department of Radiological Sciences, Division of Clinical Radiology, University Hospital "Azienda Ospedaliero Universitaria delle Marche", Ancona, Italy
| | - Marina Carotti
- Department of Clinical, Special and Dental Sciences. University Politecnica delle Marche, Ancona, Italy; Department of Radiological Sciences, Division of Clinical Radiology, University Hospital "Azienda Ospedaliero Universitaria delle Marche", Ancona, Italy
| | - Marco Valenti
- Department of Radiological Sciences, Division of Medical Physics, University Hospital "Azienda Ospedaliero Universitaria delle Marche", Ancona, Italy
| | - Andrea Giovagnoni
- Department of Clinical, Special and Dental Sciences. University Politecnica delle Marche, Ancona, Italy; Department of Radiological Sciences, Division of Clinical Radiology, University Hospital "Azienda Ospedaliero Universitaria delle Marche", Ancona, Italy
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5
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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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Euler A, Zadory M, Breiding PS, Sartoretti T, Ghafoor S, Froehlich JM, Donati OF. Realistic Kidney Tissue Surrogates for Multienergy Computed Tomography-Feasibility and Estimation of Energy-Dependent Attenuation Thresholds for Renal Lesion Enhancement in Low-kV and Virtual Monoenergetic Imaging. Invest Radiol 2021; 56:791-798. [PMID: 33899757 DOI: 10.1097/rli.0000000000000790] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
PURPOSE The aims of this study were to assess if kidney tissue surrogates (KTSs) are superior to distilled water-iodine solutions in the emulation of energy-dependent computed tomography (CT) attenuation characteristics of renal parenchyma and to estimate attenuation thresholds for definite lesion enhancement for low-kV single-energy and low-keV dual-energy virtual monoenergetic imaging. METHODS A water-filled phantom (diameter, 30 cm) with multiple vials was imaged on a dual-source dual-energy CT (DS-DE) and a single-source split-filter dual-energy CT (SF-DE), both in single-energy mode at 80, 100, 120, 140 kVp and in dual-energy mode at 80/Sn150, 90/Sn150, and 100/Sn150 kVp for DS-DE and AuSn120 kVp for SF-DE. Single-energy images, linear-blended dual-energy images, and virtual monoenergetic imaging at energy levels from 40 to 190 keV were reconstructed. First, attenuation characteristics of KTS in solid and liquid consistencies were compared. Second, solid KTSs were developed to match the CT attenuation of unenhanced renal parenchyma at 120 kVp as retrospectively measured in 100 patients. Third, CT attenuation of KTS-iodine and water-iodine solutions at 8 different iodine concentrations (0-10 mg I/mL) were compared as a function of tube voltage and of keV level using multiple linear regression models. Energy-dependent attenuation thresholds for definite lesion enhancement were calculated. RESULTS Unenhanced renal parenchyma at 120 kVp measured on average 30 HU on both scanners in the patient cohort. Solid KTS with a water content of 80% emulated the attenuation of unenhanced renal parenchyma (30 HU) more accurately compared with water-iodine solutions (0 HU). Attenuation difference between KTS-iodine and water-iodine solutions converged with increasing iodine concentration and decreasing x-ray energy due to beam-hardening effects. A slight attenuation difference of approximately 2 HU was found between the 2 CT scanners. Attenuation thresholds for definite lesion enhancement were dependent on tube voltage and keV level and ranged from 16.6 to 33.2 HU and 3.2 to 68.3 HU for single-energy and dual-energy CT scan modes for DS-DE and from 16.1 to 34.3 HU and 3.3 to 92.2 HU for SF-DE. CONCLUSIONS Kidney tissue surrogates more accurately emulate the energy-dependent CT attenuation characteristics of renal parenchyma for multienergy CT compared with conventional water-iodine approaches. Energy-dependent thresholds for definite lesion enhancement could facilitate lesion characterization when imaging at different energies than the traditional 120 kVp.
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Affiliation(s)
- André Euler
- From the Institute of Diagnostic and Interventional Radiology, University Hospital of Zurich, University of Zurich
| | | | - Philipe Sebastian Breiding
- From the Institute of Diagnostic and Interventional Radiology, University Hospital of Zurich, University of Zurich
| | | | - Soleen Ghafoor
- From the Institute of Diagnostic and Interventional Radiology, University Hospital of Zurich, University of Zurich
| | | | - Olivio Fabrizio Donati
- From the Institute of Diagnostic and Interventional Radiology, University Hospital of Zurich, University of Zurich
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van Ommen F, Kauw F, Bennink E, Heit JJ, Wolman DN, Dankbaar JW, de Jong HWAM, Wintermark M. Image Quality of Virtual Monochromatic Reconstructions of Noncontrast CT on a Dual-Source CT Scanner in Adult Patients. Acad Radiol 2021; 28:e323-e330. [PMID: 32616420 DOI: 10.1016/j.acra.2020.05.038] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Revised: 05/13/2020] [Accepted: 05/30/2020] [Indexed: 12/26/2022]
Abstract
RATIONALE AND OBJECTIVES To evaluate the image quality of virtual monochromatic images (VMI) reconstructed from dual-energy dual-source noncontrast head CT with different reconstruction kernels. MATERIALS AND METHODS Twenty-five consecutive adult patients underwent noncontrast dual-energy CT. VMI were retrospectively reconstructed at 5-keV increments from 40 to 140 keV using quantitative and head kernels. CT-number, noise levels (SD), signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) in the gray and white matter and artifacts using the posterior fossa artifact index (PFAI) were evaluated. RESULTS CT-number increased with decreasing VMI energy levels, and SD was lowest at 85 keV. SNR was maximized at 80 keV and 85 keV for the head and quantitative kernels, respectively. CNR was maximum at 40 keV; PFAI was lowest at 90 (head kernel) and 100 (quantitative kernel) keV. Optimal VMI image quality was significantly better than conventional CT. CONCLUSION Optimal image quality of VMI energies can improve brain parenchymal image quality compared to conventional CT but are reconstruction kernel dependent and depend on indication for performing noncontrast CT.
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Affiliation(s)
- Fasco van Ommen
- Department of Neuroradiology, Stanford University, Palo Alto, CA; Department of Radiology and Nuclear Medicine, University Medical Center Utrecht, Mail E01.132, P.O. Box 85500, Utrecht 3508GA, the Netherlands; Image Sciences Institute, University Medical Center Utrecht, Utrecht, the Netherlands.
| | - Frans Kauw
- Department of Neuroradiology, Stanford University, Palo Alto, CA; Department of Radiology and Nuclear Medicine, University Medical Center Utrecht, Mail E01.132, P.O. Box 85500, Utrecht 3508GA, the Netherlands
| | - Edwin Bennink
- Department of Radiology and Nuclear Medicine, University Medical Center Utrecht, Mail E01.132, P.O. Box 85500, Utrecht 3508GA, the Netherlands; Image Sciences Institute, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Jeremy J Heit
- Department of Neuroradiology, Stanford University, Palo Alto, CA
| | - Dylan N Wolman
- Department of Neuroradiology, Stanford University, Palo Alto, CA
| | - Jan Willem Dankbaar
- Department of Radiology and Nuclear Medicine, University Medical Center Utrecht, Mail E01.132, P.O. Box 85500, Utrecht 3508GA, the Netherlands
| | - Hugo W A M de Jong
- Department of Radiology and Nuclear Medicine, University Medical Center Utrecht, Mail E01.132, P.O. Box 85500, Utrecht 3508GA, the Netherlands; Image Sciences Institute, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Max Wintermark
- Department of Neuroradiology, Stanford University, Palo Alto, CA
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Wu LD, Wen K, Cheng ZR, Alwalid O, Han P. Retroperitoneal bronchogenic cyst in suprarenal region treated by laparoscopic resection: A case report. World J Clin Cases 2021; 9:7245-7250. [PMID: 34540985 PMCID: PMC8409186 DOI: 10.12998/wjcc.v9.i24.7245] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Revised: 06/10/2021] [Accepted: 07/02/2021] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Bronchogenic cysts (BCs) are benign congenital foregut malformations that are mostly present in the mediastinum and pulmonary parenchyma but rarely seen in the retroperitoneum.
CASE SUMMARY We report the case of 17-year-old girl who complained of epigastric pain. A cystic lesion was found in the left suprarenal region on spectral computed tomography. The ovoid, well-defined, and homogeneous cystic lesion revealed slightly enhancement on conventional imaging but no enhancement on 40 KeV virtual mono-energetic images. The iodine density value of the lesion was 0.001 mg/mL and the Z-effective value was 7.25, which were close to those of fluid material in in vitro experiments. Magnetic resonance imaging revealed a cystic mass of intermediate signal intensity on T1-weighted imaging and high signal intensity on T2-weighted imaging. A laparoscopic surgery was carried out. Intraoperatively, a cystic lesion with a smooth surface was found in the left retroperitoneum. And the cystic wall was completely resected after intracystic fluid was suctioned. The histopathological examination findings of the lesion were compatible with BC. The patient recovered uneventfully without sighs of recurrence during a 10-mo follow-up period.
CONCLUSION Radiological examinations play a significant role in the diagnosis of suprarenal BCs and spectral images offer additional spectral parameters. Accurate preoperative diagnoses of retroperitoneal BCs based on thorough imaging examinations are beneficial to the operation of laparoscopic resection.
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Affiliation(s)
- Lei-Di Wu
- Department of Radiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430000, Hubei Province, China
| | - Kan Wen
- Department of Radiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430000, Hubei Province, China
| | - Zi-Rui Cheng
- Department of Urology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430000, Hubei Province, China
| | - Osamah Alwalid
- Department of Radiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430000, Hubei Province, China
| | - Ping Han
- Department of Radiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430000, Hubei Province, China
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Effect of energy level on the spatial resolution and noise frequency characteristics of virtual monochromatic images: a phantom experiment using four types of CT scanners. Jpn J Radiol 2021; 40:94-102. [PMID: 34304382 DOI: 10.1007/s11604-021-01180-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: 04/04/2021] [Accepted: 07/19/2021] [Indexed: 10/20/2022]
Abstract
PURPOSE The purpose of the study is to evaluate the effect of energy level on the modulation transfer functions (MTF) and noise power spectra (NPS) of virtual monochromatic images (VMIs) obtained using four types of computed-tomographic (CT) scanners: Revolution, SOMATOM, IQon, and Aquilion. MATERIALS AND METHODS VMIs were obtained at 70, 60, and 50 kiloelectron volts (keV), and also at the lowest keV available in each scanner. We evaluated the MTF and NPS in the VMIs obtained at each keV. RESULTS No significant effect of the energy level on the MTF was observed in IQon, whereas the spatial resolution decreased as the energy level decreased in the other types of scanners. The NPS curves tended to increase as the energy levels decreased with three types of scanners other than Aquilion. CONCLUSION The spatial resolution and noise frequency characteristics of VMIs may be affected by the energy level, and the effects of energy level on these characteristics differ depending on the type of CT scanners.
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Han D, Yu Y, He T, Yu N, Dang S, Wu H, Ren J, Duan X. Effect of radiomics from different virtual monochromatic images in dual-energy spectral CT on the WHO/ISUP classification of clear cell renal cell carcinoma. Clin Radiol 2021; 76:627.e23-627.e29. [PMID: 33985770 DOI: 10.1016/j.crad.2021.02.033] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2020] [Accepted: 02/10/2021] [Indexed: 12/24/2022]
Abstract
AIM To investigate the effect of radiomics obtained from different virtual monochromatic images (VMIs) in dual-energy spectral computed tomography (CT) on the World Health Organization/International Association for Urological Pathology (WHO/ISUP) classification of clear cell renal cell carcinoma (ccRCC). MATERIALS AND METHODS A retrospective study of 99 ccRCC patients who underwent contrast-enhanced dual-energy CT was undertaken. ccRCC was confirmed at surgery or biopsy and graded according to the WHO/ISUP pathological grading criteria as low grade (n=68, grade I and II) or high grade (n=31, grade III and IV). Radiomics risk scores (RRSs) for differentiating high and low grades of ccRCC were constructed from 11 sets of VMI in (40-140 keV, 10 keV interval) the cortical phase. Receiver operating characteristic (ROC) curves were drawn and the area under the curves (AUCs) was calculated to evaluate the discriminatory power of RRS for each VMI. The Hosmer-Lemeshow test was used to evaluate the goodness-of-fit of each model and the decision curve was used to analyse its net benefit to patients. RESULTS The AUC values for distinguishing low-from high-grade ccRCC with RRS of 40-140 keV VMIs were all >0.920. The Hosmer-Lemeshow test showed that the p-values of RRS of VMIs were >0.05, suggesting good fits. In the decision curve analysis, RRS from the 40-140 keV VMIs had similar decision curves and provided better net benefits than considering all patients either as high-grade or low-grade. CONCLUSIONS The RRS obtained from multiple VMIs in dual-energy spectral CT have high diagnostic efficiencies for distinguishing between low- and high-grade ccRCC with no significant differences between different VMIs.
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Affiliation(s)
- D Han
- Department of Medical Image, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China
| | - Y Yu
- Department of Radiology, Affiliated Hospital of Shaanxi University of Chinese Medicine, Xianyang, Shaanxi, China
| | - T He
- Department of Radiology, Affiliated Hospital of Shaanxi University of Chinese Medicine, Xianyang, Shaanxi, China
| | - N Yu
- Department of Radiology, Affiliated Hospital of Shaanxi University of Chinese Medicine, Xianyang, Shaanxi, China
| | - S Dang
- Department of Medical Image, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China
| | - H Wu
- Pathology Department, Affiliated Hospital of Shaanxi University of Chinese Medicine, Xianyang, Shaanxi, China
| | - J Ren
- GE Healthcare China, Beijing, China
| | - X Duan
- Department of Medical Image, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, China.
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Papadakis AE, Damilakis J. Technical Note: Quality assessment of virtual monochromatic spectral images on a dual energy CT scanner. Phys Med 2021; 82:114-121. [DOI: 10.1016/j.ejmp.2021.01.079] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Revised: 01/26/2021] [Accepted: 01/29/2021] [Indexed: 12/11/2022] Open
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Evaluation of Spatial Resolution of Virtual Monochromatic Imaging In Vitro: Effect of Energy Level and Contrast. J Comput Assist Tomogr 2021; 45:93-97. [PMID: 32976256 DOI: 10.1097/rct.0000000000001046] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE Our aim was to evaluate effects of the energy level and contrast on the spatial resolution of virtual monochromatic imaging (VMI). METHODS With 2 types of computed tomographic (CT) scanners (Discovery CT750 HD and Revolution CT), we scanned an elliptical cylinder acrylic phantom with 20- or 40-fold dilutions of contrast medium and obtained VMI data sets at 40, 50, 60, and 70 keV. We evaluated the effects of energy levels and contrast on modulation transfer function (MTF) and the effect of energy levels on noise power spectra (NPS). RESULTS With both CT scanners, MTF decreased significantly as the energy level decreased. The effect of the dilution of contrast media on MTF varied with CT scanners. With both scanners, NPS curves demonstrate uniform increase in NPS across the entire spatial frequency as the energy levels decreased. CONCLUSIONS The energy level and contrast can affect the spatial resolution of VMIs.
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Jacobsen MC, Thrower SL. Multi-energy computed tomography and material quantification: Current barriers and opportunities for advancement. Med Phys 2020; 47:3752-3771. [PMID: 32453879 PMCID: PMC8495770 DOI: 10.1002/mp.14241] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Revised: 04/20/2020] [Accepted: 05/07/2020] [Indexed: 12/21/2022] Open
Abstract
Computed tomography (CT) technology has rapidly evolved since its introduction in the 1970s. It is a highly important diagnostic tool for clinicians as demonstrated by the significant increase in utilization over several decades. However, much of the effort to develop and advance CT applications has been focused on improving visual sensitivity and reducing radiation dose. In comparison to these areas, improvements in quantitative CT have lagged behind. While this could be a consequence of the technological limitations of conventional CT, advanced dual-energy CT (DECT) and photon-counting detector CT (PCD-CT) offer new opportunities for quantitation. Routine use of DECT is becoming more widely available and PCD-CT is rapidly developing. This review covers efforts to address an unmet need for improved quantitative imaging to better characterize disease, identify biomarkers, and evaluate therapeutic response, with an emphasis on multi-energy CT applications. The review will primarily discuss applications that have utilized quantitative metrics using both conventional and DECT, such as bone mineral density measurement, evaluation of renal lesions, and diagnosis of fatty liver disease. Other topics that will be discussed include efforts to improve quantitative CT volumetry and radiomics. Finally, we will address the use of quantitative CT to enhance image-guided techniques for surgery, radiotherapy and interventions and provide unique opportunities for development of new contrast agents.
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Affiliation(s)
- Megan C. Jacobsen
- Department of Imaging Physics, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Sara L. Thrower
- Department of Imaging Physics, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
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Patel BN, Boltyenkov AT, Martinez MG, Mastrodicasa D, Marin D, Jeffrey RB, Chung B, Pandharipande P, Kambadakone A. Cost-effectiveness of dual-energy CT versus multiphasic single-energy CT and MRI for characterization of incidental indeterminate renal lesions. Abdom Radiol (NY) 2020; 45:1896-1906. [PMID: 31894384 DOI: 10.1007/s00261-019-02380-x] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
PURPOSE To evaluate the cost-effectiveness of DECT versus multiphasic CT and MRI for characterizing small incidentally detected indeterminate renal lesions using a Markov Monte Carlo decision-analytic model. BACKGROUND Incidental renal lesions are commonly encountered due to the increasing utilization of medical imaging and the increasing prevalence of renal lesions with age. Currently recommended imaging modalities to further characterize incidental indeterminate renal lesions have some inherent drawbacks. Single-phase DECT may overcome these limitations, but its cost-effectiveness remains uncertain. MATERIALS AND METHODS A decision-analytic (Markov) model was constructed to estimate life expectancy and lifetime costs for otherwise healthy 64-year-old patients with small (≤ 4 cm) incidentally detected, indeterminate renal lesions on routine imaging (e.g., ultrasound or single-phase CT). Three strategies for evaluating renal lesions for enhancement were compared: multiphase SECT (e.g., true unenhanced and nephrographic phase), multiphasic MRI, and single-phase DECT (nephrographic phase in dual-energy mode). The model incorporated modality-specific diagnostic test performance, incidence, and prevalence of incidental renal cell carcinomas (RCCs), effectiveness, costs, and health outcomes. An incremental cost-effectiveness analysis was performed to identify strategy preference at willingness-to-pay (WTP) thresholds of $50,000 and $100,000 per quality-adjusted life-year (QALY) gained. Deterministic and probabilistic sensitivity analysis were performed. RESULTS In the base case analysis, expected mean costs per patient undergoing characterization of incidental renal lesions were $2567 for single-phase DECT, $3290 for multiphasic CT, and $3751 for multiphasic MRI. Associated quality-adjusted life-years were the highest for single-phase DECT at 0.962, for multiphasic MRI it was 0.940, and was the lowest for multiphasic CT at 0.925. Because of lower associated costs and higher effectiveness, the single-phase DECT strategy dominated the other two strategies. CONCLUSIONS Single-phase DECT is potentially more cost-effective than multiphasic SECT and MRI for evaluating small incidentally detected indeterminate renal lesions.
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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: 11.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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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: 1.3] [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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Çamlıdağ İ, Nural MS, Danacı M, Özden E. Usefulness of rapid kV-switching dual energy CT in renal tumor characterization. Abdom Radiol (NY) 2019; 44:1841-1849. [PMID: 30637472 DOI: 10.1007/s00261-019-01897-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
PURPOSE To investigate whether iodine content can discriminate between benign or malignant renal tumors, malign tumor subtypes, low-grade and high-grade tumors on rapid kv-switching dual-energy CT (rsDECT). METHODS This prospective study enrolled 95 patients with renal tumors who underwent rsDECT for tumor characterization between 2016 and 2018. Attenuation on true and virtual unenhanced images, absolute enhancement and enhancement ratio and iodine content of each lesion on nephrographic phase iodine density images were measured. Histopathological diagnosis was obtained following either surgery or core biopsy. RESULTS Eighty-five tumors were renal cell carcinoma (RCC) (56 clear cell, 20 papillary, 9 chromophobe) and 10 were benign (6 angiomyolipoma,4 oncocytoma). 46 tumors were low-grade and 23 high-grade. There was significant difference between iodine content of clear cell and non-clear cell (papillary + chromophobe) RCC (p < 0.001). However, no significant iodine content differences were found between papillary and chromophobe RCC, benign and malignant tumors, low-grade and high-grade tumors. The best cut-off iodine content for differentiating clear cell from non-clear cell RCC was 3.2 mg/ml and clear cell from papillary RCC was 2.9 mg/ml with a high sensitivity and specificity. Also, significant difference was found between attenuation values of true and virtual unenhanced images (p = 0.007). Mean iodine content, absolute enhancement and enhancement ratio were highly correlated. CONCLUSION rsDECT contributes to renal tumor characterization by showing higher iodine content in clear cell RCCs compared with non-clear cell RCCs.
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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: 85] [Impact Index Per Article: 14.2] [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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Dual-Energy CT Material Density Iodine Quantification for Distinguishing Vascular From Nonvascular Renal Lesions: Normalization Reduces Intermanufacturer Threshold Variability. AJR Am J Roentgenol 2019; 212:366-376. [DOI: 10.2214/ajr.18.20115] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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Soesbe TC, Ananthakrishnan L, Lewis MA, Duan X, Nasr K, Xi Y, Abbara S, Leyendecker JR, Lenkinski RE. Pseudoenhancement effects on iodine quantification from dual-energy spectral CT systems: A multi-vendor phantom study regarding renal lesion characterization. Eur J Radiol 2018; 105:125-133. [DOI: 10.1016/j.ejrad.2018.06.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2017] [Revised: 04/12/2018] [Accepted: 06/01/2018] [Indexed: 01/30/2023]
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Wortman JR, Sodickson AD. Pearls, Pitfalls, and Problems in Dual-Energy Computed Tomography Imaging of the Body. Radiol Clin North Am 2018; 56:625-640. [PMID: 29936951 DOI: 10.1016/j.rcl.2018.03.007] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Dual-energy computed tomography (DECT) is an exciting technology that is increasing in routine use and has the potential for significant clinical impact. With the advancement of DECT, it is important for radiologists to be aware of potential challenges with DECT acquisition and postprocessing, and to have a basic knowledge of unique artifacts and diagnostic pitfalls that can occur when interpreting DECT scans and DECT postprocessed images. This article serves as a practical overview of potential problems and diagnostic pitfalls associated with DECT, and steps that can be taken to avoid them.
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Affiliation(s)
- Jeremy R Wortman
- Division of Emergency Radiology, Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, 75 Francis Street, Boston, MA 02115, USA.
| | - Aaron D Sodickson
- Division of Emergency Radiology, Department of Radiology, Brigham and Women's Hospital, Harvard Medical School, 75 Francis Street, Boston, MA 02115, USA
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22
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Vernuccio F, Meyer M, Mileto A, Marin D. Use of Dual-Energy Computed Tomography for Evaluation of Genitourinary Diseases. Urol Clin North Am 2018; 45:297-310. [PMID: 30031456 DOI: 10.1016/j.ucl.2018.03.012] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Since its clinical inception a decade ago, dual-energy computed tomography has expanded the array of computed tomography imaging tools available to the practicing abdominal radiologist. Of note, diagnostic solutions for imaging-based evaluation of genitourinary diseases, foremost kidney calculi and renal tumors characterization, represent the apogee applications of dual-energy computed tomography in abdominal imaging. This article reviews clinical applications of dual-energy computed tomography for the assessment of genitourinary diseases.
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Affiliation(s)
- Federica Vernuccio
- Department of Radiology, Duke University Medical Center, Box 3808 Erwin Road, Durham, NC 27710, USA; Section of Radiology -Di.Bi.Med., University Hospital "Paolo Giaccone", University of Palermo, Via del Vespro 129, 90127, Palermo, Italy
| | - Mathias Meyer
- Department of Radiology, Duke University Medical Center, Box 3808 Erwin Road, Durham, NC 27710, USA
| | - Achille Mileto
- Department of Radiology, University of Washington School of Medicine, Box 357115, 1959 Northeast Pacific Street, Seattle, WA 98195, USA
| | - Daniele Marin
- Department of Radiology, Duke University Medical Center, Box 3808 Erwin Road, Durham, NC 27710, USA.
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Patel BN, Marin D. Strategies to Improve Image Quality on Dual-Energy Computed Tomography. Radiol Clin North Am 2018; 56:641-647. [PMID: 29936952 DOI: 10.1016/j.rcl.2018.03.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Dual-energy computed tomography (DECT) offers several advantages over conventional single-energy CT. These advantages include improved image quality, beam hardening correction, and metal artifact reduction. Additionally, DECT allows derivation of quantitative information through material decomposition analysis. Although newer third-generation rapid-kilovolt switching and dual-source DECT scanners have significantly improved in image quality and workflow compared with initial iterations and early scanners, sources of potential image quality degradation can exist secondary to the inherent capabilities in which the image acquisition occurs.
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Affiliation(s)
- Bhavik N Patel
- Division of Abdominal Imaging, Department of Radiology, Stanford University School of Medicine, 300 Pasteur Drive, H1307, Stanford, CA 94305, USA.
| | - Daniele Marin
- Division of Abdominal Imaging, Department of Radiology, Duke University, DUMC 3808, Durham, NC 27710, USA
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Rajiah P, Rong R, Martinez-Rios C, Rassouli N, Landeras L. Benefit and clinical significance of retrospectively obtained spectral data with a novel detector-based spectral computed tomography - Initial experiences and results. Clin Imaging 2018; 49:65-72. [DOI: 10.1016/j.clinimag.2017.10.019] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Revised: 10/06/2017] [Accepted: 10/27/2017] [Indexed: 01/08/2023]
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Hélénon O, Crosnier A, Verkarre V, Merran S, Méjean A, Correas JM. Simple and complex renal cysts in adults: Classification system for renal cystic masses. Diagn Interv Imaging 2018; 99:189-218. [DOI: 10.1016/j.diii.2017.10.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2017] [Accepted: 09/26/2017] [Indexed: 02/08/2023]
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Energy-Specific Optimization of Attenuation Thresholds for Low-Energy Virtual Monoenergetic Images in Renal Lesion Evaluation. AJR Am J Roentgenol 2018; 210:W205-W217. [PMID: 29547057 DOI: 10.2214/ajr.17.18641] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
OBJECTIVE The purpose of this study was to determine in vitro and in vivo the optimal threshold for renal lesion vascularity at low-energy (40-60 keV) virtual monoenergetic imaging. MATERIALS AND METHODS A rod simulating unenhanced renal parenchymal attenuation (35 HU) was fitted with a syringe containing water. Three iodinated solutions (0.38, 0.57, and 0.76 mg I/mL) were inserted into another rod that simulated enhanced renal parenchyma (180 HU). Rods were inserted into cylindric phantoms of three different body sizes and scanned with single- and dual-energy MDCT. In addition, 102 patients (32 men, 70 women; mean age, 66.8 ± 12.9 [SD] years) with 112 renal lesions (67 nonvascular, 45 vascular) measuring 1.1-8.9 cm underwent single-energy unenhanced and contrast-enhanced dual-energy CT. Optimal threshold attenuation values that differentiated vascular from nonvascular lesions at 40-60 keV were determined. RESULTS Mean optimal threshold values were 30.2 ± 3.6 (standard error), 20.9 ± 1.3, and 16.1 ± 1.0 HU in the phantom, and 35.9 ± 3.6, 25.4 ± 1.8, and 17.8 ± 1.8 HU in the patients at 40, 50, and 60 keV. Sensitivity and specificity for the thresholds did not change significantly between low-energy and 70-keV virtual monoenergetic imaging (sensitivity, 87-98%; specificity, 90-91%). The AUC from 40 to 70 keV was 0.96 (95% CI, 0.93-0.99) to 0.98 (95% CI, 0.95-1.00). CONCLUSION Low-energy virtual monoenergetic imaging at energy-specific optimized attenuation thresholds can be used for reliable characterization of renal lesions.
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Abstract
Pancreatic adenocarcinoma is a common malignancy that has a poor prognosis. Imaging is vital in its detection, staging, and management. Although a variety of imaging techniques are available, MDCT is the preferred imaging modality for staging and assessing the resectability of pancreatic adenocarcinoma. MR also has an important adjunct role, and may be used in addition to CT or as a problem-solving tool. A dedicated pancreatic protocol should be acquired as a biphasic technique optimized for the detection of pancreatic adenocarcinoma and to allow accurate local and distant disease staging. Emerging techniques like dual-energy CT and texture analysis of CT and MR images have a great potential in improving lesion detection, characterization, and treatment monitoring.
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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: 2.4] [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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Abstract
Renal cell carcinoma (RCC) exhibits a diverse and heterogeneous disease spectrum, but insight into its molecular biology has provided an improved understanding of potential risk factors, oncologic behavior, and imaging features. Computed tomography (CT) and MR imaging may allow the identification and preoperative subtyping of RCC and assessment of a response to various therapies. Active surveillance is a viable management option in some patients and has provided further insight into the natural history of RCC, including the favorable prognosis of cystic neoplasms. This article reviews CT and MR imaging in RCC and the role of screening in selected high-risk populations.
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Affiliation(s)
- Alberto Diaz de Leon
- Department of Radiology, University of Texas Southwestern Medical Center, 2201 Inwood Road, 2nd Floor, Suite 202, Dallas, TX 75390-9085, USA
| | - Ivan Pedrosa
- Department of Radiology, University of Texas Southwestern Medical Center, 2201 Inwood Road, 2nd Floor, Suite 202, Dallas, TX 75390-9085, USA.
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Characterization of Small (< 4 cm) Focal Renal Lesions: Diagnostic Accuracy of Spectral Analysis Using Single-Phase Contrast-Enhanced Dual-Energy CT. AJR Am J Roentgenol 2017; 209:815-825. [DOI: 10.2214/ajr.17.17824] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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Marino MA, Silipigni S, Barbaro U, Mazziotti S, Sofia C, Mazzei MA, Ascenti G. Dual Energy CT Scanning in Evaluation of the Urinary Tract. CURRENT RADIOLOGY REPORTS 2017; 5:46. [DOI: 10.1007/s40134-017-0243-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Sugisawa K, Ichikawa K, Minamishima K, Hasegawa M, Yamada Y, Jinzaki M. Evaluation of the CT Parameters to Suppress Renal Cysts Pseudoenhancement Effect: Influence of the Virtual Monochromatic Spectral Images, the Model-based Iterative Reconstruction Algorithm and the Aperture Size in Phantom Model. Nihon Hoshasen Gijutsu Gakkai Zasshi 2017; 73:636-645. [PMID: 28824087 DOI: 10.6009/jjrt.2017_jsrt_73.8.636] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
PURPOSE The purpose of this study was to evaluate the effect of the virtual monochromatic spectral images (VMSI) and the model-based iterative reconstruction (MBIR) images, to evaluate the influence of the aperture size (40- and 20-mm beam) on renal pseudoenhancement (PE) compared with the filtered back projection (FBP) images. METHODS The renal compartment-CT phantom was filled with iodinated contrast material diluted to the attenuation of 180 Hounsfield units (HU) at 120 kV. The water-filled spherical structures, which simulate cyst, were inserted into the renal compartment. Those diameters were 7, 15 and 25 mm. These were scanned by conventional mode (helical scan, 120 kV-FBP) and dual energy mode. 70 keV-VMSI were reconstructed from the dual energy mode, and MBIR images were reconstructed from conventional mode at 40- and 20-mm aperture. Additionally, the phantom was scanned using non-helical mode with 20-mm aperture, and FBP images were reconstructed. The CT value of the PE for cyst areas was measured for these images. RESULTS The CT values of the cysts were 20.0-14.3 HU on the FBP images, 12.8-12.7 HU on the 70 keV-VMSI (PE-inhibition ratio was 36.0-11.2%) and 16.2-14.0 HU on the MBIR images (19.0-2.1%), respectively, at 40-mm aperture. The PE-inhibition ratio scanned by 20-mm aperture was improved by 28.0% with FBP, 32.8% with 70 keV-VMSI and 29.6% with MBIR compared with 40-mm aperture. One of the FBP images with non-helical mode was 11.6 HU. CONCLUSIONS The best CT technique to minimize PE was the combination of 70 keV-VMSI and 20-mm aperture.
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Affiliation(s)
- Koichi Sugisawa
- Graduate School of Medical Science, Kanazawa University.,Department of Radiological Technology, Keio University Hospital
| | - Katsuhiro Ichikawa
- Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University
| | | | | | - Yoshitake Yamada
- Department of Diagnostic Radiology, Keio University School of Medicine
| | - Masahiro Jinzaki
- Department of Diagnostic Radiology, Keio University School of Medicine
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Han D, Ma G, Wei L, Ren C, Zhou J, Shen C, He T. Preliminary study on the differentiation between parapelvic cyst and hydronephrosis with non-calculous using only pre-contrast dual-energy spectral CT scans. Br J Radiol 2017; 90:20160632. [PMID: 28281789 DOI: 10.1259/bjr.20160632] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
OBJECTIVE To investigate the value of using the quantitative parameters from only the pre-contrast dual-energy spectral CT imaging for distinguishing between parapelvic cyst and hydronephrosis with non-calculous (HNC). METHODS This retrospective study was approved by the institutional review board. 28 patients with parapelvic cyst and 24 patients with HNC who underwent standard pre-contrast and multiphase contrast-enhanced dual-energy spectral CT imaging were retrospectively identified. The parapelvic cyst and HNC were identified using the contrast-enhanced scans, and their CT number in the 70-keV monochromatic images, effective atomic number (Zeff), iodine concentration (IC) and water concentration in the pre-contrast images were measured. The slope of the spectral curve (λ) was calculated. The difference in the measurements between parapelvic cyst and HNC was statistically analyzed using SPSS® v. 19.0 (IBM Corp., New York, NY; formerly SPSS Inc., Chicago, IL) statistical software. Receiver-operating characteristic analysis was performed to assess the diagnostic performance. RESULTS The CT numbers in the 70-keV images, Zeff and IC values were statistically different between parapelvic cyst and HNC (all p < 0.05). The sensitivity, specificity and accuracy of these parameters for distinguishing between parapelvic cyst and HNC were 89.2%, 73.3% and 82.1%; 86.5%, 43.3% and 67.2%; 91.9%, 40.0% and 68.7%; and 64.9%, 73.3% and 83.6%, respectively, and the combined specificity was 92.9%. There was no statistical difference in λ between the two groups (p > 0.05). CONCLUSION The quantitative parameters obtained in the pre-contrast dual-energy spectral CT imaging may be used to differentiate between parapelvic cyst and HNC. Advances in knowledge: The pre-contrast dual-energy spectral CT scans may be used to screen parapelvic cysts for patients who are asymptomatic, thereby avoiding contrast-enhanced CT or CT urography examination for these patients to reduce ionizing radiation dose and contrast dose.
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Affiliation(s)
- Dong Han
- 1 College of Medical Technology, Shaanxi University of Traditional Chinese Medicine, Xianyang, Shaanxi, China
| | - Guangming Ma
- 2 Department of Radiology, Affiliated Hospital of Shaanxi University of Traditional Chinese Medicine, Xianyang, Shaanxi, China
| | - Lequn Wei
- 1 College of Medical Technology, Shaanxi University of Traditional Chinese Medicine, Xianyang, Shaanxi, China
| | - Chenglong Ren
- 2 Department of Radiology, Affiliated Hospital of Shaanxi University of Traditional Chinese Medicine, Xianyang, Shaanxi, China
| | - Jieli Zhou
- 3 Department of Ultrasound, Xijing Hospital, Fourth Military Medical University of PLA, Xi'an, Shaanxi, China
| | - Chen Shen
- 1 College of Medical Technology, Shaanxi University of Traditional Chinese Medicine, Xianyang, Shaanxi, China
| | - Taiping He
- 2 Department of Radiology, Affiliated Hospital of Shaanxi University of Traditional Chinese Medicine, Xianyang, Shaanxi, China
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Abstract
Reignited by innovations in scanner engineering and software design, dual-energy computed tomography (CT) has come back into the clinical radiology arena in the last decade. Possibilities for noninvasive in vivo characterization of genitourinary disease, especially for renal stones and renal masses, have become the pinnacle offerings of dual-energy CT for body imaging in clinical practice. This article renders a state-of-the-art review on clinical applications of dual-energy CT in genitourinary imaging.
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Affiliation(s)
- Achille Mileto
- Department of Radiology, University of Washington School of Medicine, Box 357115, 1959 Northeast Pacific Street, Seattle, WA 98195, USA
| | - Daniele Marin
- Department of Radiology, Duke University Medical Center, Box 3808 Erwin Road, Durham, NC 27710, USA.
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Hélénon O, Delavaud C, Dbjay J, Gregory J, Rasouli N, Correas JM. A Practical Approach to Indeterminate and Cystic Renal Masses. Semin Ultrasound CT MR 2016; 38:10-27. [PMID: 28237276 DOI: 10.1053/j.sult.2016.09.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Cystic renal masses are a common entity with a wide differential diagnosis encountered by the radiologist in daily practice. Their characterization relies on the Bosniak classification system that has been widely accepted by radiologists and urologists as a pertinent diagnostic and communication tool. It has been designed to separate cystic lesions requiring surgery (categories III and IV) from those that can be ignored and left alone (categories I and II) or followed (category IIF). Utilization of the Bosniak classification requires, first, previous identification of the cystic nature of a renal mass with the exception of very small lesions.
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Affiliation(s)
- Olivier Hélénon
- Paris Descartes Medical School, Paris Descartes University, Paris, France; Department of Adult Radiology, Necker Hospital, Paris, France.
| | - Christophe Delavaud
- Paris Descartes Medical School, Paris Descartes University, Paris, France; Department of Adult Radiology, Necker Hospital, Paris, France
| | - Jonathan Dbjay
- Paris Descartes Medical School, Paris Descartes University, Paris, France; Department of Adult Radiology, Necker Hospital, Paris, France
| | - Jules Gregory
- Paris Descartes Medical School, Paris Descartes University, Paris, France; Department of Adult Radiology, Necker Hospital, Paris, France
| | | | - Jean-Michel Correas
- Paris Descartes Medical School, Paris Descartes University, Paris, France; Department of Adult Radiology, Necker Hospital, Paris, France
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Dual-Energy CT of Incidental Findings in the Abdomen: Can We Reduce the Need for Follow-Up Imaging? AJR Am J Roentgenol 2016; 207:W58-W68. [DOI: 10.2214/ajr.16.16087] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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Mileto A, Barina A, Marin D, Stinnett SS, Roy Choudhury K, Wilson JM, Nelson RC. Virtual Monochromatic Images from Dual-Energy Multidetector CT: Variance in CT Numbers from the Same Lesion between Single-Source Projection-based and Dual-Source Image-based Implementations. Radiology 2016; 279:269-77. [DOI: 10.1148/radiol.2015150919] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Mileto A, Sofue K, Marin D. Imaging the renal lesion with dual-energy multidetector CT and multi-energy applications in clinical practice: what can it truly do for you? Eur Radiol 2016; 26:3677-90. [DOI: 10.1007/s00330-015-4180-7] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2015] [Revised: 12/16/2015] [Accepted: 12/18/2015] [Indexed: 01/30/2023]
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Utility of MRI in the Characterization of Indeterminate Small Renal Lesions Previously Seen on Screening CT Scans of Potential Renal Donor Patients. AJR Am J Roentgenol 2015. [PMID: 26204282 DOI: 10.2214/ajr.14.13956] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
OBJECTIVE The purpose of this study was to determine whether MRI could more confidently characterize indeterminate small renal lesions (< 15 mm) previously seen on CT scans of potential renal donor patients and whether such characterization could impact surgical management and donor candidate status. MATERIALS AND METHODS After dedicated contrast-enhanced renal CT examinations of a population of renal donor patients identified indeterminate small renal lesions (< 15 mm), dedicated renal MRI examinations were performed for 55 of those patients. Two radiologists used consensus reading of established MRI characteristics to characterize indeterminate small lesions as simple cysts, hemorrhagic cysts, angiomyolipomas, or solid renal masses. RESULTS A total of 94 indeterminate small renal lesions were detected on CT. MRI was able to confidently diagnose 93 of those lesions, including 83 cysts, eight hemorrhagic cysts, and two angiomyolipomas. MRI directly affected the surgical management of four of the patients (7%). CONCLUSION For potential renal donor patients, MRI can be an effective means of characterizing lesions that are deemed to be too small to characterize by CT. MRI can also potentially alter the surgical management and donor status of this group of patients.
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Abstract
Although conceived of in the 1970s, practical use of dual-energy CT in the clinical setting did not come to fruition until 2006, and since that time an ever expanding exploration of the technology has been underway. This article will discuss technical aspects of the two commercially available CT scanners, review the recent literature, and provide an organ-based description of abdominal dual-energy CT applications for the practicing radiologist.
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Yamada Y, Yamada M, Sugisawa K, Akita H, Shiomi E, Abe T, Okuda S, Jinzaki M. Renal cyst pseudoenhancement: intraindividual comparison between virtual monochromatic spectral images and conventional polychromatic 120-kVp images obtained during the same CT examination and comparisons among images reconstructed using filtered back projection, adaptive statistical iterative reconstruction, and model-based iterative reconstruction. Medicine (Baltimore) 2015; 94:e754. [PMID: 25881852 PMCID: PMC4602515 DOI: 10.1097/md.0000000000000754] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
The purpose of this study was to compare renal cyst pseudoenhancement between virtual monochromatic spectral (VMS) and conventional polychromatic 120-kVp images obtained during the same abdominal computed tomography (CT) examination and among images reconstructed using filtered back projection (FBP), adaptive statistical iterative reconstruction (ASIR), and model-based iterative reconstruction (MBIR). Our institutional review board approved this prospective study; each participant provided written informed consent. Thirty-one patients (19 men, 12 women; age range, 59-85 years; mean age, 73.2 ± 5.5 years) with renal cysts underwent unenhanced 120-kVp CT followed by sequential fast kVp-switching dual-energy (80/140 kVp) and 120-kVp abdominal enhanced CT in the nephrographic phase over a 10-cm scan length with a random acquisition order and 4.5-second intervals. Fifty-one renal cysts (maximal diameter, 18.0 ± 14.7 mm [range, 4-61 mm]) were identified. The CT attenuation values of the cysts as well as of the kidneys were measured on the unenhanced images, enhanced VMS images (at 70 keV) reconstructed using FBP and ASIR from dual-energy data, and enhanced 120-kVp images reconstructed using FBP, ASIR, and MBIR. The results were analyzed using the mixed-effects model and paired t test with Bonferroni correction. The attenuation increases (pseudoenhancement) of the renal cysts on the VMS images reconstructed using FBP/ASIR (least square mean, 5.0/6.0 Hounsfield units [HU]; 95% confidence interval, 2.6-7.4/3.6-8.4 HU) were significantly lower than those on the conventional 120-kVp images reconstructed using FBP/ASIR/MBIR (least square mean, 12.1/12.8/11.8 HU; 95% confidence interval, 9.8-14.5/10.4-15.1/9.4-14.2 HU) (all P < .001); on the other hand, the CT attenuation values of the kidneys on the VMS images were comparable to those on the 120-kVp images. Regardless of the reconstruction algorithm, 70-keV VMS images showed a lower degree of pseudoenhancement of renal cysts than 120-kVp images, while maintaining kidney contrast enhancement comparable to that on 120-kVp images.
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Affiliation(s)
- Yoshitake Yamada
- From the Department of Diagnostic Radiology (YY, KS, HA, ES, SO, MJ), Keio University School of Medicine; Multi-dimension Biomedical Imaging & Information Laboratory in Research Park (MY), Keio University School of Medicine; and Department of Preventive Medicine and Public Health, Center for Clinical Research, Keio University School of Medicine (TA), Shinjuku-ku, Tokyo, Japan
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He J, Wang Q, Ma X, Sun Z. Dual-energy CT angiography of abdomen with routine concentration contrast agent in comparison with conventional single-energy CT with high concentration contrast agent. Eur J Radiol 2015; 84:221-7. [DOI: 10.1016/j.ejrad.2014.11.025] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2014] [Revised: 11/14/2014] [Accepted: 11/18/2014] [Indexed: 10/24/2022]
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Hu S, Huang W, Chen Y, Song Q, Lin X, Wang Z, Chen K. Spectral CT evaluation of interstitial brachytherapy in pancreatic carcinoma xenografts: preliminary animal experience. Eur Radiol 2014; 24:2167-73. [PMID: 24903229 DOI: 10.1007/s00330-014-3257-z] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2013] [Revised: 05/05/2014] [Accepted: 05/21/2014] [Indexed: 12/11/2022]
Abstract
OBJECTIVES We sought to evaluate the capability of spectral CT to detect the therapeutic response to (125)I interstitial brachytherapy in a pancreatic carcinoma xenograft nude mouse model. METHODS Twenty mice bearing SWl990 human pancreatic cancer cell xenografts were randomly separated into two groups: experimental (n = 10; 1.0 mCi) and control (n = 10; 0 mCi). After a two-week treatment, spectral CT was performed. Contrast-to-noise ratio (CNR) and iodine concentration (IC) in the lesions were measured and normalized to the muscle tissue, and nIC CD31 immunohistochemistry was used to measure microvessel density (MVD). The relationships between the nIC and MVD of the tumours were analysed. RESULTS The nIC of the experimental group was significantly lower than that of the control group during the multiphase examination. A significant difference in the MVD was observed between the two groups (P <0.001). The nIC values of the three-phase scans have a certain positive correlation with MVD (r = 0.57, p < 0.0001; r = 0.48, p = 0.002; r = 0.63, p = 0.0017 in the 10, 25, and 60 s phase, respectively). CONCLUSIONS Spectral CT can be a useful non-invasive imaging modality in evaluating the therapeutic effect of (125)I interstitial brachytherapy to a pancreatic carcinoma. KEY POINTS Spectral CT offers opportunities to assess therapeutic response in pancreatic cancer cases. Spectral CT findings correlated with vascular changes associated with (125)I seed implantation. Spectral CT with monochromatic imaging removed most (125)I seed artefacts.
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Affiliation(s)
- Shudong Hu
- Department of Radiology, The Affiliated Renmin Hospital, Jiangsu University, Zhenjiang, Jiangsu, 212002, China,
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Marin D, Fananapazir G, Mileto A, Choudhury KR, Wilson JM, Nelson RC. Dual-Energy Multi–Detector Row CT with Virtual Monochromatic Imaging for Improving Patient-to-Patient Uniformity of Aortic Enhancement during CT Angiography: An in Vitro and in Vivo Study. Radiology 2014; 272:895-902. [DOI: 10.1148/radiol.14132857] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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Abstract
Recent technologic advances in computed tomography (CT)--enabling the nearly simultaneous acquisition of clinical images using two different x-ray energy spectra--have sparked renewed interest in dual-energy CT. By interrogating the unique characteristics of different materials at different x-ray energies, dual-energy CT can be used to provide quantitative information about tissue composition, overcoming the limitations of attenuation-based conventional single-energy CT imaging. In the past few years, intensive research efforts have been devoted to exploiting the unique and powerful opportunities of dual-energy CT for a variety of clinical applications. This has led to CT protocol modifications for radiation dose reduction, improved diagnostic performance for detection and characterization of diseases, as well as image quality optimization. In this review, the authors discuss the basic principles, instrumentation and design, examples of current clinical applications in the abdomen and pelvis, and future opportunities of dual-energy CT.
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Affiliation(s)
- Daniele Marin
- From the Department of Radiology, Duke University Medical Center, Box 3808, Room 1531, Erwin Rd, Durham, NC 27710
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Mileto A, Nelson RC, Samei E, Jaffe TA, Paulson EK, Barina A, Choudhury KR, Wilson JM, Marin D. Impact of dual-energy multi-detector row CT with virtual monochromatic imaging on renal cyst pseudoenhancement: in vitro and in vivo study. Radiology 2014; 272:767-76. [PMID: 24844472 DOI: 10.1148/radiol.14132856] [Citation(s) in RCA: 88] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
PURPOSE To investigate whether dual-energy multi-detector row computed tomography (CT) with virtual monochromatic imaging can overcome renal cyst pseudoenhancement in a phantom experiment and a clinical study. MATERIALS AND METHODS This retrospective single-center HIPAA-compliant study was approved by the institutional review board, with waiver of informed consent. Four renal compartments inserted into torso phantoms were filled with saline to simulate the unenhanced state and with iodinated solutions to simulate the three levels of renal parenchyma enhancement (140, 180, and 240 HU). Saline-filled spheres simulating renal cysts (15 and 18 mm in diameter) were serially suspended in the renal compartments and imaged with dual-energy and single-energy multi-detector row CT at four different energy levels (80, 100, 120, and 140 kVp). In addition, 28 patients (mean age, 66 years ± 10; mean body mass index, 31.3 kg/m(2) ± 6.2) with 34 intrarenal cysts were included. Virtual monochromatic images were reconstructed in 10-keV increments at energy levels ranging from 40 to 140 keV. Phantom and clinical data were analyzed by using multivariate regression analysis. RESULTS In the phantom experiment, all polychromatic image data sets showed pseudoenhancement (postcontrast attenuation increase >10 HU) in all investigated conditions, with a significant effect on cyst size (P <.001), location (P <.001), and renal background attenuation level (P <.001). Virtual monochromatic images at energy levels ranging from 80 to 140 keV did not show pseudoenhancement, with the minimum attenuation increase (mean, 6.1 HU ± 1.6; range, 1.6-7.7 HU) on 80-keV images. In patients, pseudoenhancement never occurred on virtual monochromatic images at energy levels ranging from 90 to 140 keV. Patient body size had a significant effect (P = .007) on selection of the optimal monochromatic energy level. CONCLUSION Dual-energy multi-detector row CT with reconstruction of virtual monochromatic images at an optimal energy level can overcome renal cyst pseudoenhancement.
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Affiliation(s)
- Achille Mileto
- From the Department of Radiology (A.M., R.C.N., T.A.J., E.K.P., A.B., D.M.) and Carl E. Ravin Advanced Imaging Laboratories (E.S., K.R.C., J.M.W.), Duke University Medical Center, Box 3808 Erwin Rd, Durham, NC 27710
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Spectral CT demonstration of the superior mesenteric artery: comparison of monochromatic and polychromatic imaging. Acad Radiol 2014; 21:364-8. [PMID: 24360636 DOI: 10.1016/j.acra.2013.11.004] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2013] [Revised: 10/31/2013] [Accepted: 11/03/2013] [Indexed: 12/11/2022]
Abstract
RATIONALE AND OBJECTIVES To investigate the performance of spectral computed tomography (CT) in depiction of the superior mesenteric artery (SMA) compared to conventional polychromatic CT. MATERIALS AND METHODS This prospective study had institutional review board approval, and written informed consent was obtained. Fifty patients underwent spectral CT examination using gemstone spectral imaging with a single-tube, fast dual-tube voltage-switching technique. Spectrum analysis was used to select the monochromatic images that provide the optimal contrast-to-noise ratio (CNR) for SMA angiography. The CNR for SMA at the selected monochromatic level was compared with that from the conventional polychromatic images. Image quality and visibility of the branch order of SMA were also assessed and compared. RESULTS The monochromatic images at 50 keV (mean 50.09 ± 1.98) provided the optimal CNR for SMA angiography. At this energy level, the monochromatic images had higher (20.8 vs 9.2) CNR than the polychromatic images, and the image quality was superior to conventional polychromatic images (P < .05). Fourth to fifth (mean 4.3) and third to fourth (mean 3.5) order branches of SMA were demonstrated at monochromatic and polychromatic images, respectively. CONCLUSIONS Gemstone spectral imaging with monochromatic images at 50 keV by spectral CT could improve the CTA image quality and demonstrate more branch order in depiction of normal SMA compared to conventional polychromatic imaging.
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Graumann O, Osther SS, Karstoft J, Hørlyck A, Osther PJS. Evaluation of Bosniak category IIF complex renal cysts. Insights Imaging 2013; 4:471-80. [PMID: 23673454 PMCID: PMC3731465 DOI: 10.1007/s13244-013-0251-y] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2012] [Revised: 03/29/2013] [Accepted: 04/16/2013] [Indexed: 12/02/2022] Open
Abstract
PURPOSE To evaluate moderately complex renal cysts of Bosniak category IIF. MATERIALS AND METHODS The regional ethics committee approved the study. In the period 2003-2009, radiological CT reports of 8,402 CT examinations of the kidneys were analysed retrospectively by one radiologist. All complex cystic lesions in the kidney (n = 550 in the same number of patients) were reclassified according to the Bosniak classification by two radiologists in consensus. If a patient had more than one lesion, only the highest Bosniak category was recorded. All Bosniak IIF lesions with ≥2-year follow-up were included in the study. RESULTS Thirty-two Bosniak IIF lesions were found. Five lesions (16 %) were upgraded during follow-up and the patients were offered surgery. Pathology of three lesions showed papillary carcinoma, clear cell renal carcinoma and chronic inflammation, respectively. Due to comorbidity the remaining two patients were followed with CT without intervention. Ten lesions (31 %) with follow-up periods >5 years had no further radiological changes and clinical follow-up was stopped. CONCLUSION The use of Bosniak category IIF is clinically applicable, resulting in an overall surgical nephron-sparing approach to complex renal cysts. TEACHING POINTS • The Bosniak classification is used to categorise complex renal cystic masses • BIIF cysts behave mostly as benign lesions • Radiological progression in complexity occurs in only 16 % of cases • BIIF category seems promising for clinical application, potentially avoiding unnecessary surgery.
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Affiliation(s)
- Ole Graumann
- Urological Research Center, Department of Urology, Fredericia Hospital, Fredericia, and Institute of Regional Health Services Research, University of Southern Denmark, Dronningensgade 97, DK-7000 Fredericia, Denmark
| | - Susanne Sloth Osther
- Urological Research Center, Department of Urology, Fredericia Hospital, Fredericia, and Institute of Regional Health Services Research, University of Southern Denmark, Dronningensgade 97, DK-7000 Fredericia, Denmark
| | - Jens Karstoft
- Department of Radiology, Odense University Hospital, Sdr. Boulevard 29, 5000 Odense, Denmark
| | - Arne Hørlyck
- Department of Radiology, Aarhus University Hospital, Brendstrupgårdsvej 100, Skejby, Denmark
| | - Palle Jörn Sloth Osther
- Urological Research Center, Department of Urology, Fredericia Hospital, Fredericia, and Institute of Regional Health Services Research, University of Southern Denmark, Dronningensgade 97, DK-7000 Fredericia, Denmark
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