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Werner S, Krauss B, Horger M. Dual-energy CT based monitoring of treatment-induced bone marrow changes in lung cancer patients: preliminary results. Quant Imaging Med Surg 2022; 12:1871-1881. [DOI: 10.21037/qims-21-545] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2021] [Accepted: 11/01/2021] [Indexed: 11/06/2022]
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Kosmala A, Gruschwitz P, Veldhoen S, Weng AM, Krauss B, Bley TA, Petritsch B. Correction to: Dual-energy CT angiography in suspected pulmonary embolism: infuence of injection protocols on image quality and perfused blood volume. Int J Cardiovasc Imaging 2021; 38:707. [PMID: 34767144 DOI: 10.1007/s10554-021-02439-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
- Aleksander Kosmala
- Department of Diagnostic and Interventional Radiology, University Hospital Würzburg, Oberdürrbacher Straße 6, 97080, Würzburg, Germany.
| | - Philipp Gruschwitz
- Department of Diagnostic and Interventional Radiology, University Hospital Würzburg, Oberdürrbacher Straße 6, 97080, Würzburg, Germany
| | - Simon Veldhoen
- Department of Diagnostic and Interventional Radiology, University Hospital Würzburg, Oberdürrbacher Straße 6, 97080, Würzburg, Germany
| | - Andreas Max Weng
- Department of Diagnostic and Interventional Radiology, University Hospital Würzburg, Oberdürrbacher Straße 6, 97080, Würzburg, Germany
| | - Bernhard Krauss
- Siemens Healthcare GmbH, Research and Development, Forchheim, Germany
| | - Thorsten Alexander Bley
- Department of Diagnostic and Interventional Radiology, University Hospital Würzburg, Oberdürrbacher Straße 6, 97080, Würzburg, Germany
| | - Bernhard Petritsch
- Department of Diagnostic and Interventional Radiology, University Hospital Würzburg, Oberdürrbacher Straße 6, 97080, Würzburg, Germany
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McFadden K, Krauss B, Ma I, Vivian R, Gullikson J, Al Saud A, Huang C, Liteplo A, Shokoohi H. 140 Patient Performed Thoracic Lung Ultrasound. Ann Emerg Med 2021. [DOI: 10.1016/j.annemergmed.2021.09.150] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Müller FC, Gosvig KK, Mikkel Ø, Bjarne R, Rodell A, Henrik B, Krauss B, Gade JS, Boesen M. Quantifying the bone marrow composition of the healthy adult wrist with dual-energy CT. Eur J Radiol 2021; 139:109725. [PMID: 33878568 DOI: 10.1016/j.ejrad.2021.109725] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Revised: 03/22/2021] [Accepted: 04/14/2021] [Indexed: 10/21/2022]
Abstract
PURPOSE Purpose of this study was to investigate Dual-energy CT (DECT) derived virtual non-calcium (VNCa) values for absolute quantification of the bone marrow composition in the wrist. MATERIALS AND METHODS We prospectively included consecutive adult participants and examined their wrists with DECT. Ranges of VNCa and calcium values were measured in the carpal bones, radius and ulna using a semi-automatic method. Bones with bone marrow edema, assessed by two blinded radiologists, were excluded. After determining optimum parameters for the three-material decomposition, the influence of calcium values, age and sex on VNCa values was assessed using multiple linear regression. RESULTS 41 participants (Median age 53 years, range 20 years - 88 years, 51 % men) were enrolled and 399 bones assessed. At participant level mean VNCa values were -143 HU (SD 14 HU) using the current parameters for three-material decomposition and -104HU (SD 11 HU) with optimized parameters. There was a strong and significant influence of calcium values on VNCa values with the current parameters (p < 0.001, -0.137 HU[VNCa] / HU[Calcium]). With optimized parameters the calcium values and sex were not statistically significant predictors of VNCa values. Age was a significant, but clinically negligible, predictor (p = 0.03, -0.225 HU / year). CONCLUSIONS After optimizing three-material decomposition parameters, calcium values, age and sex do not substantially influence virtual non-calcium values, and DECT may therefore be used for absolute quantification of the bone marrow composition - alleviating the need for reference bones or groups.
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Affiliation(s)
- Felix C Müller
- Department of Radiology, Herlev and Gentofte Hospital, Borgmester Ib Juuls Vej 17, 2730, Herlev, Denmark; Siemens Healthineers, Borupvang 9, 2750, Ballerup, Denmark.
| | - Kasper K Gosvig
- Department of Radiology, Herlev and Gentofte Hospital, Borgmester Ib Juuls Vej 17, 2730, Herlev, Denmark
| | - Østergaard Mikkel
- Copenhagen Center for Arthritis Research, Center for Rheumatology and Spine Diseases, Rigshospitalet, Valdemar Hansens Vej 1-23, Glostrup, Denmark; Department of Clinical Medicine, University of Copenhagen, Blegdamsvej 3B, 2200, København, Copenhagen, Denmark
| | - Roed Bjarne
- Siemens Healthineers, Borupvang 9, 2750, Ballerup, Denmark
| | - Anders Rodell
- Siemens Healthineers, Borupvang 9, 2750, Ballerup, Denmark
| | - Børgesen Henrik
- Department of Radiology, Herlev and Gentofte Hospital, Borgmester Ib Juuls Vej 17, 2730, Herlev, Denmark
| | - Bernhard Krauss
- Siemens Healthineers, Siemensstraße 1, 91301, Forchheim, Germany
| | - Jesper S Gade
- Department of Radiology, Sygehus Lillebælt, Beriderbakken 4, 7100, Vejle, Denmark
| | - Mikael Boesen
- Department of Radiology, Bispebjerg and Frederiksberg Hospital, Bispebjerg Bakke 23, 2400, København, Denmark
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Kosmala A, Gruschwitz P, Veldhoen S, Weng AM, Krauss B, Bley TA, Petritsch B. Dual-energy CT angiography in suspected pulmonary embolism: influence of injection protocols on image quality and perfused blood volume. Int J Cardiovasc Imaging 2020; 36:2051-2059. [PMID: 32506286 PMCID: PMC8692293 DOI: 10.1007/s10554-020-01911-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/13/2020] [Accepted: 06/02/2020] [Indexed: 12/16/2022]
Abstract
To compare intravenous contrast material (CM) injection protocols for dual-energy CT pulmonary angiography (CTPA) in patients with suspected acute pulmonary embolism with regard to image quality and pulmonary perfused blood volume (PBV) values. A total of 198 studies performed with four CM injection protocols varying in CM volume and iodine delivery rates (IDR) were retrospectively included: (A) 60 ml at 5 ml/s (IDR = 1.75gI/s), (B) 50 ml at 5 ml/s (IDR = 1.75gI/s), (C) 50 ml at 4 ml/s (IDR = 1.40gI/s), (D) 40 ml at 3 ml/s (IDR = 1.05gI/s). Image quality and PBV values at different resolution settings were compared. Pulmonary arterial tract attenuation was highest for protocol A (397 ± 110 HU; p vs. B = 0.13; vs. C = 0.02; vs. D < 0.001). CTPA image quality of protocol A was rated superior compared to protocols B and D by reader 1 (p = 0.01; < 0.001), and superior to protocols B, C and D by reader 2 (p < 0.001; 0.02; < 0.001). Otherwise, there were no significant differences in CTPA quality ratings. Subjective iodine map ratings did not vary significantly between protocols A, B, and C. Both readers rated protocol D inferior to all other protocols (p < 0.05). PBV values did not vary significantly between protocols A and B at resolution settings of 1, 4 and 10 (p = 0.10; 0.10; 0.09), while otherwise PBV values displayed a decreasing trend from protocol A to D (p < 0.05). Higher CM volume and IDR are associated with superior CTPA and iodine map quality and higher absolute PBV values.
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Affiliation(s)
- Aleksander Kosmala
- Department of Diagnostic and Interventional Radiology, University Hospital Würzburg, Oberdürrbacher Straße 6, 97080, Würzburg, Germany.
| | - Philipp Gruschwitz
- Department of Diagnostic and Interventional Radiology, University Hospital Würzburg, Oberdürrbacher Straße 6, 97080, Würzburg, Germany
| | - Simon Veldhoen
- Department of Diagnostic and Interventional Radiology, University Hospital Würzburg, Oberdürrbacher Straße 6, 97080, Würzburg, Germany
| | - Andreas Max Weng
- Department of Diagnostic and Interventional Radiology, University Hospital Würzburg, Oberdürrbacher Straße 6, 97080, Würzburg, Germany
| | - Bernhard Krauss
- Siemens Healthcare GmbH, Research and Development, Forchheim, Germany
| | - Thorsten Alexander Bley
- Department of Diagnostic and Interventional Radiology, University Hospital Würzburg, Oberdürrbacher Straße 6, 97080, Würzburg, Germany
| | - Bernhard Petritsch
- Department of Diagnostic and Interventional Radiology, University Hospital Würzburg, Oberdürrbacher Straße 6, 97080, Würzburg, Germany
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Lazar M, Ringl H, Baltzer P, Toth D, Seitz C, Krauss B, Unger E, Polanec S, Tamandl D, Herold CJ, Toepker M. Protocol analysis of dual-energy CT for optimization of kidney stone detection in virtual non-contrast reconstructions. Eur Radiol 2020; 30:4295-4305. [DOI: 10.1007/s00330-020-06806-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2019] [Revised: 03/02/2020] [Accepted: 03/11/2020] [Indexed: 12/12/2022]
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Müller FC, Børgesen H, Gosvig K, Rodell A, Booz C, Schmidt B, Krauss B, Boesen M. Optimising dual-energy CT scan parameters for virtual non-calcium imaging of the bone marrow: a phantom study. Eur Radiol Exp 2019; 3:46. [PMID: 31802305 PMCID: PMC6892987 DOI: 10.1186/s41747-019-0125-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Accepted: 09/16/2019] [Indexed: 11/10/2022] Open
Abstract
Background We investigated the influence of dose, spectral separation, pitch, rotation time, and reconstruction kernel on accuracy and image noise of virtual non-calcium images using a bone marrow phantom. Methods The phantom was developed at our institution and scanned using a third-generation dual-source dual-energy CT scanner at five different spectral separations by varying the tube-voltage combinations (70 kV/Sn150 kV, 80 kV/Sn150 kV, 90 kV/Sn150 kV, and 100 kV/Sn150 kV, all with 0.6-mm tin filter [Sn]; 80 kV/140 kV without tin filter) at six different doses (volume computed tomography dose index from 1 to 80 mGy). In separate experiments, rotation times, pitch, and reconstruction kernels were varied at a constant dose and tube voltage. Accuracy was determined by measuring the mean error between virtual non-calcium values in the fluid within and outside of the bone. Image noise was defined as the standard deviation of virtual non-calcium values. Results Spectral separation, dose, rotation time, or pitch did not significantly correlate (p > 0.083) with mean error. Increased spectral separation (rs-0.96, p < 0.001) and increased dose (rs-0.98, p < 0.001) correlated significantly with decreased image noise. Increasing sharpness of the reconstruction kernel correlated with mean error (rs 0.83, p = 0.015) and image noise (rs 1.0, p < 0.001). Conclusions Increased dose and increased spectral separation significantly lowered image noise in virtual non-calcium images but did not affect the accuracy. Virtual non-calcium reconstructions with similar accuracy and image noise could be achieved at a lower tube-voltage difference by increasing the dose.
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Affiliation(s)
- Felix C Müller
- Department of Radiology, Herlev and Gentofte Hospital, Herlev, Denmark. .,Siemens Healthineers, Ballerup, Denmark.
| | - Henrik Børgesen
- Department of Radiology, Herlev and Gentofte Hospital, Herlev, Denmark
| | - Kasper Gosvig
- Department of Radiology, Herlev and Gentofte Hospital, Herlev, Denmark
| | | | - Christian Booz
- Division of Experimental and Translational Imaging, Department of Diagnostic and Interventional Radiology, University Hospital Frankfurt, Frankfurt, Germany
| | | | | | - Mikael Boesen
- Department of Radiology, Bispebjerg and Frederiksberg Hospital, Frederiksberg, Denmark
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Kim TM, Choi YH, Cheon JE, Kim WS, Kim IO, Park JE, Shin SM, Pak SY, Krauss B. Optimal Kiloelectron Volt for Noise-Optimized Virtual Monoenergetic Images of Dual-Energy Pediatric Abdominopelvic Computed Tomography: Preliminary Results. Korean J Radiol 2019; 20:283-294. [PMID: 30672168 PMCID: PMC6342763 DOI: 10.3348/kjr.2017.0507] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2017] [Accepted: 04/30/2018] [Indexed: 12/11/2022] Open
Abstract
Objective To compare quantitative and qualitative image quality parameters in pediatric abdominopelvic dual-energy CT (DECT) using noise-optimized virtual monoenergetic image (VMI) and conventional VMI at different kiloelectron volt (keV) levels. Materials and Methods Thirty-six consecutive abdominopelvic DECT scans were retrospectively included. Noise-optimized VMI and conventional VMI were reconstructed at seven energy levels, from 40 keV to 100 keV at 10 keV intervals. The contrast-to-noise ratio (CNR) and signal-to-noise ratio (SNR) of the liver, pancreas, and aorta were objectively measured and compared. Image quality was evaluated subjectively regarding image noise, image blurring of solid organ, bowel image quality and severity of beam-hardening artifacts. Optimal monoenergetic levels in keV for both algorithms were determined based on overall image quality score. Results The maximal CNR and SNR values for all investigated organs were observed at 40 keV in noise-optimized VMI (CNR and SNR of liver, pancreas, aorta in order [CNR; 20.93, 17.34, 46.75: SNR; 37.39, 33.80, 63.21]), at 60–70 keV and at 70 keV in conventional VMI (CNR; 8.12, 5.67, 15.97: SNR; 19.57, 16.66, 26.65). In qualitative image analysis, noise-optimized VMI and conventional VMI showed the best overall image quality scores at 60 keV and at 70 keV, respectively. Noise-optimized VMI at 60 keV showed superior CNRs, SNRs, and overall image quality scores compared to conventional VMI at 70 keV (p < 0.001). Conclusion Optimal energy levels for noise-optimized VMI and conventional VMI were 60 keV and at 70 keV, respectively. Noise-optimized VMI shows superior CNRs, SNRs and subjective image quality over conventional VMI, at the optimal energy level.
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Affiliation(s)
- Taek Min Kim
- Department of Radiology, Seoul National University Hospital, Seoul, Korea.,Department of Radiology, Seoul National University College of Medicine, Seoul, Korea
| | - Young Hun Choi
- Department of Radiology, Seoul National University Hospital, Seoul, Korea.,Department of Radiology, Seoul National University College of Medicine, Seoul, Korea.
| | - Jung Eun Cheon
- Department of Radiology, Seoul National University Hospital, Seoul, Korea.,Department of Radiology, Seoul National University College of Medicine, Seoul, Korea.,Institute of Radiation Medicine, Seoul National University Medical Research Center, Seoul, Korea
| | - Woo Sun Kim
- Department of Radiology, Seoul National University Hospital, Seoul, Korea.,Department of Radiology, Seoul National University College of Medicine, Seoul, Korea.,Institute of Radiation Medicine, Seoul National University Medical Research Center, Seoul, Korea
| | - In One Kim
- Department of Radiology, Seoul National University Hospital, Seoul, Korea.,Department of Radiology, Seoul National University College of Medicine, Seoul, Korea.,Institute of Radiation Medicine, Seoul National University Medical Research Center, Seoul, Korea
| | - Ji Eun Park
- Department of Radiology, Kyung Hee University Hospital, Seoul, Korea
| | - Su Mi Shin
- Department of Radiology, Seoul Metropolitan Government-Seoul National University Boramae Medical Center, Seoul, Korea
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Werner S, Krauss B, Haberland U, Bongers M, Starke U, Bakchoul T, Enkel S, Nikolaou K, Horger M. Dual-energy CT for liver iron quantification in patients with haematological disorders. Eur Radiol 2018; 29:2868-2877. [DOI: 10.1007/s00330-018-5785-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Revised: 08/28/2018] [Accepted: 09/20/2018] [Indexed: 12/22/2022]
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Kosmala A, Weng AM, Krauss B, Knop S, Bley TA, Petritsch B. Dual-energy CT of the bone marrow in multiple myeloma: diagnostic accuracy for quantitative differentiation of infiltration patterns. Eur Radiol 2018; 28:5083-5090. [DOI: 10.1007/s00330-018-5537-5] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2018] [Revised: 05/01/2018] [Accepted: 05/14/2018] [Indexed: 12/21/2022]
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Euler A, Obmann MM, Szucs-Farkas Z, Mileto A, Zaehringer C, Falkowski AL, Winkel DJ, Marin D, Stieltjes B, Krauss B, Schindera ST. Comparison of image quality and radiation dose between split-filter dual-energy images and single-energy images in single-source abdominal CT. Eur Radiol 2018; 28:3405-3412. [DOI: 10.1007/s00330-018-5338-x] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2017] [Revised: 01/09/2018] [Accepted: 01/17/2018] [Indexed: 12/25/2022]
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Taasti VT, Michalak GJ, Hansen DC, Deisher AJ, Kruse JJ, Krauss B, Muren LP, Petersen JBB, McCollough CH. Validation of proton stopping power ratio estimation based on dual energy CT using fresh tissue samples. Phys Med Biol 2017; 63:015012. [PMID: 29057753 DOI: 10.1088/1361-6560/aa952f] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Dual energy CT (DECT) has been shown, in theoretical and phantom studies, to improve the stopping power ratio (SPR) determination used for proton treatment planning compared to the use of single energy CT (SECT). However, it has not been shown that this also extends to organic tissues. The purpose of this study was therefore to investigate the accuracy of SPR estimation for fresh pork and beef tissue samples used as surrogates of human tissues. The reference SPRs for fourteen tissue samples, which included fat, muscle and femur bone, were measured using proton pencil beams. The tissue samples were subsequently CT scanned using four different scanners with different dual energy acquisition modes, giving in total six DECT-based SPR estimations for each sample. The SPR was estimated using a proprietary algorithm (syngo.via DE Rho/Z Maps, Siemens Healthcare, Forchheim, Germany) for extracting the electron density and the effective atomic number. SECT images were also acquired and SECT-based SPR estimations were performed using a clinical Hounsfield look-up table. The mean and standard deviation of the SPR over large volume-of-interests were calculated. For the six different DECT acquisition methods, the root-mean-square errors (RMSEs) for the SPR estimates over all tissue samples were between 0.9% and 1.5%. For the SECT-based SPR estimation the RMSE was 2.8%. For one DECT acquisition method, a positive bias was seen in the SPR estimates, having a mean error of 1.3%. The largest errors were found in the very dense cortical bone from a beef femur. This study confirms the advantages of DECT-based SPR estimation although good results were also obtained using SECT for most tissues.
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Affiliation(s)
- Vicki T Taasti
- Department of Medical Physics, Aarhus University Hospital, Aarhus, Denmark. Author to whom any correspondence should be addressed
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Michalak G, Taasti V, Krauss B, Deisher A, Halaweish A, McCollough C. A comparison of relative proton stopping power measurements across patient size using dual- and single-energy CT. Acta Oncol 2017; 56:1465-1471. [PMID: 28885130 DOI: 10.1080/0284186x.2017.1372625] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
PURPOSE To evaluate the accuracy and precision across phantom size of a dual-energy computed tomography (DECT) technique used to calculate relative proton stopping power (SPR) in tissue-simulating materials and a silicone implant relative to conventional single-energy CT (SECT). MATERIAL AND METHODS A 32 cm lateral diameter (CIRS model 062M, Norfolk, Virginia) electron density phantom containing inserts which simulated the chemical composition of eight tissues in a solid-water background was scanned using SECT and DECT. A liquid water insert was included to confirm CT number accuracy. All materials were also placed in four water tanks, ranging from 15 to 45 cm in lateral width and scanned using DECT and SECT. A silicone breast implant was scanned in the same water phantoms. SPR values were calculated based on commercial software (syngo CT Dual Energy, Siemens Healthcare GmbH) and compared to reference values derived from proton beam measurements. Accuracy and precision were quantified across phantom size using percent error and standard deviation. Graphical and regression analysis were used to determine whether SECT or DECT was superior in estimating SPR across phantom size. RESULTS Both DECT and SECT SPR data resulted in good agreement with the reference values. Percent error was ±3% for both DECT and SECT in all materials except lung and dense bone. The coefficient of variation (CV) across materials and phantom sizes was 1.12% for SECT and 0.96% for DECT. Material-specific regression and graphical analysis did not reveal size dependence for either technique but did show reduced systematic bias with DECT for dense bone and liver. Mean percent error in SPR for the implant was reduced from 11.46% for SECT to 0.49% for DECT. CONCLUSIONS We demonstrate the superior ability of DECT to mitigate systematic bias in bones and liver and estimate SPR in a silicone breast implant.
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Affiliation(s)
| | - Vicki Taasti
- Department of Medical Physics, Aarhus University Hospital, Aarhus, Denmark
| | | | - Amanda Deisher
- Department of Radiation Oncology, Mayo Clinic, Rochester, MN, USA
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Leng S, Zhou W, Yu Z, Halaweish A, Krauss B, Schmidt B, Yu L, Kappler S, McCollough C. Spectral performance of a whole-body research photon counting detector CT: quantitative accuracy in derived image sets. Phys Med Biol 2017; 62:7216-7232. [PMID: 28726669 DOI: 10.1088/1361-6560/aa8103] [Citation(s) in RCA: 67] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Photon-counting computed tomography (PCCT) uses a photon counting detector to count individual photons and allocate them to specific energy bins by comparing photon energy to preset thresholds. This enables simultaneous multi-energy CT with a single source and detector. Phantom studies were performed to assess the spectral performance of a research PCCT scanner by assessing the accuracy of derived images sets. Specifically, we assessed the accuracy of iodine quantification in iodine map images and of CT number accuracy in virtual monoenergetic images (VMI). Vials containing iodine with five known concentrations were scanned on the PCCT scanner after being placed in phantoms representing the attenuation of different size patients. For comparison, the same vials and phantoms were also scanned on 2nd and 3rd generation dual-source, dual-energy scanners. After material decomposition, iodine maps were generated, from which iodine concentration was measured for each vial and phantom size and compared with the known concentration. Additionally, VMIs were generated and CT number accuracy was compared to the reference standard, which was calculated based on known iodine concentration and attenuation coefficients at each keV obtained from the U.S. National Institute of Standards and Technology (NIST). Results showed accurate iodine quantification (root mean square error of 0.5 mgI/cc) and accurate CT number of VMIs (percentage error of 8.9%) using the PCCT scanner. The overall performance of the PCCT scanner, in terms of iodine quantification and VMI CT number accuracy, was comparable to that of EID-based dual-source, dual-energy scanners.
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Affiliation(s)
- Shuai Leng
- Department of Radiology, Mayo Clinic, 200 First St SW, Rochester, MN 55905, United States of America
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Symons R, Krauss B, Sahbaee P, Cork TE, Lakshmanan MN, Bluemke DA, Pourmorteza A. Photon-counting CT for simultaneous imaging of multiple contrast agents in the abdomen: An in vivo study. Med Phys 2017; 44:5120-5127. [PMID: 28444761 DOI: 10.1002/mp.12301] [Citation(s) in RCA: 124] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2016] [Revised: 04/07/2017] [Accepted: 04/14/2017] [Indexed: 02/02/2023] Open
Abstract
PURPOSE To demonstrate the feasibility of spectral imaging using photon-counting detector (PCD) x-ray computed tomography (CT) for simultaneous material decomposition of three contrast agents in vivo in a large animal model. METHODS This Institutional Animal Care and Use Committee-approved study used a canine model. Bismuth subsalicylate was administered orally 24-72 h before imaging. PCD CT was performed during intravenous administration of 40-60 ml gadoterate meglumine; 3.5 min later, iopamidol 370 was injected intravenously. Renal PCD CT images were acquired every 2 s for 5-6 min to capture the wash-in and wash-out kinetics of the contrast agents. Least mean squares linear material decomposition was used to calculate the concentrations of contrast agents in the aorta, renal cortex, renal medulla and renal pelvis. RESULTS Using reference vials with known concentrations of materials, we computed molar concentrations of the various contrast agents during each phase of CT scanning. Material concentration maps allowed simultaneous quantification of both arterial and delayed renal enhancement in a single CT acquisition. The accuracy of the material decomposition algorithm in a test phantom was -0.4 ± 2.2 mM, 0.3 ± 2.2 mM for iodine and gadolinium solutions, respectively. Peak contrast concentration of gadolinium and iodine in the aorta, renal cortex, and renal medulla were observed 16, 24, and 60 s after the start each injection, respectively. CONCLUSION Photon-counting spectral CT allowed simultaneous material decomposition of multiple contrast agents in vivo. Besides defining contrast agent concentrations, tissue enhancement at multiple phases was observed in a single CT acquisition, potentially obviating the need for multiphase CT scans and thus reducing radiation dose.
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Affiliation(s)
- Rolf Symons
- Radiology Imaging Sciences, National Institutes of Health Clinical Center, Bethesda, MD, USA
| | - Bernhard Krauss
- Computed Tomography Division, Siemens Healthcare GmbH, Forchheim, Germany
| | - Pooyan Sahbaee
- Imaging and Therapy Systems, Siemens Medical Solutions Inc., Malvern, PA, USA
| | - Tyler E Cork
- Radiology Imaging Sciences, National Institutes of Health Clinical Center, Bethesda, MD, USA
| | - Manu N Lakshmanan
- Radiology Imaging Sciences, National Institutes of Health Clinical Center, Bethesda, MD, USA
| | - David A Bluemke
- Radiology Imaging Sciences, National Institutes of Health Clinical Center, Bethesda, MD, USA
| | - Amir Pourmorteza
- Radiology Imaging Sciences, National Institutes of Health Clinical Center, Bethesda, MD, USA
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Kosmala A, Weng AM, Heidemeier A, Krauss B, Knop S, Bley TA, Petritsch B. Multiple Myeloma and Dual-Energy CT: Diagnostic Accuracy of Virtual Noncalcium Technique for Detection of Bone Marrow Infiltration of the Spine and Pelvis. Radiology 2017; 286:205-213. [PMID: 28799843 DOI: 10.1148/radiol.2017170281] [Citation(s) in RCA: 82] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Purpose To determine the diagnostic performance of dual-energy computed tomography (CT) for detection of bone marrow (BM) infiltration in patients with multiple myeloma by using a virtual noncalcium (VNCa) technique. Materials and Methods In this prospective study, 34 consecutive patients with multiple myeloma or monoclonal gammopathy of unknown significance sequentially underwent dual-energy CT and magnetic resonance (MR) imaging of the axial skeleton. Two independent readers visually evaluated standard CT and color-coded VNCa images for the presence of BM involvement. MR imaging served as the reference standard. Analysis on the basis of the region of interest (ROI) of VNCa CT numbers of infiltrated (n = 75) and normal (n = 170) BM was performed and CT numbers were subjected to receiver operating characteristic analysis to calculate cutoff values. Results In the visual analysis, VNCa images had an overall sensitivity of 91.3% (21 of 23), specificity of 90.9% (10 of 11), accuracy of 91.2% (31 of 34), positive predictive value of 95.5% (21 of 22), and a negative predictive value of 83.3% (10 of 12). ROI-based analysis of VNCa CT numbers showed a significant difference between infiltrated and normal BM (P < .001). Receiver operating characteristic analysis revealed an area under the curve of 0.978. A cutoff of -44.9 HU provided a sensitivity of 93.3% (70 of 75), specificity of 92.4% (157 of 170), accuracy of 92.7% (227 of 245), positive predictive value of 84.3% (70 of 83), and negative predictive value of 96.9% (157 of 162) for the detection of BM infiltration. Conclusion Visual and ROI-based analyses of dual-energy VNCa images had excellent diagnostic performance for assessing BM infiltration in patients with multiple myeloma with precision comparable to that of MR imaging. © RSNA, 2017 Online supplemental material is available for this article.
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Affiliation(s)
- Aleksander Kosmala
- From the Departments of Diagnostic and Interventional Radiology (A.K., A.M.W., A.H., T.A.B., B.P.) and Internal Medicine II (S.K.), University Hospital Würzburg, Oberdürrbacherstr 6, 97080 Würzburg, Germany; and Department of Diagnostic Imaging, Siemens Healthcare, Forchheim, Germany (B.K.)
| | - Andreas Max Weng
- From the Departments of Diagnostic and Interventional Radiology (A.K., A.M.W., A.H., T.A.B., B.P.) and Internal Medicine II (S.K.), University Hospital Würzburg, Oberdürrbacherstr 6, 97080 Würzburg, Germany; and Department of Diagnostic Imaging, Siemens Healthcare, Forchheim, Germany (B.K.)
| | - Anke Heidemeier
- From the Departments of Diagnostic and Interventional Radiology (A.K., A.M.W., A.H., T.A.B., B.P.) and Internal Medicine II (S.K.), University Hospital Würzburg, Oberdürrbacherstr 6, 97080 Würzburg, Germany; and Department of Diagnostic Imaging, Siemens Healthcare, Forchheim, Germany (B.K.)
| | - Bernhard Krauss
- From the Departments of Diagnostic and Interventional Radiology (A.K., A.M.W., A.H., T.A.B., B.P.) and Internal Medicine II (S.K.), University Hospital Würzburg, Oberdürrbacherstr 6, 97080 Würzburg, Germany; and Department of Diagnostic Imaging, Siemens Healthcare, Forchheim, Germany (B.K.)
| | - Stefan Knop
- From the Departments of Diagnostic and Interventional Radiology (A.K., A.M.W., A.H., T.A.B., B.P.) and Internal Medicine II (S.K.), University Hospital Würzburg, Oberdürrbacherstr 6, 97080 Würzburg, Germany; and Department of Diagnostic Imaging, Siemens Healthcare, Forchheim, Germany (B.K.)
| | - Thorsten Alexander Bley
- From the Departments of Diagnostic and Interventional Radiology (A.K., A.M.W., A.H., T.A.B., B.P.) and Internal Medicine II (S.K.), University Hospital Würzburg, Oberdürrbacherstr 6, 97080 Würzburg, Germany; and Department of Diagnostic Imaging, Siemens Healthcare, Forchheim, Germany (B.K.)
| | - Bernhard Petritsch
- From the Departments of Diagnostic and Interventional Radiology (A.K., A.M.W., A.H., T.A.B., B.P.) and Internal Medicine II (S.K.), University Hospital Würzburg, Oberdürrbacherstr 6, 97080 Würzburg, Germany; and Department of Diagnostic Imaging, Siemens Healthcare, Forchheim, Germany (B.K.)
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Petritsch B, Kosmala A, Weng AM, Krauss B, Heidemeier A, Wagner R, Heintel TM, Gassenmaier T, Bley TA. Vertebral Compression Fractures: Third-Generation Dual-Energy CT for Detection of Bone Marrow Edema at Visual and Quantitative Analyses. Radiology 2017; 284:161-168. [DOI: 10.1148/radiol.2017162165] [Citation(s) in RCA: 79] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Bernhard Petritsch
- From the Departments of Diagnostic and Interventional Radiology (B.P., A.K., A.M.W., A.H., T.G., T.A.B.) and Trauma, Hand, Plastic and Reconstructive Surgery (R.W., T.M.H.), University Hospital Würzburg, Oberdürrbacher Str 6, D-97080 Würzburg, Germany; Imaging and Therapy Division, Siemens Healthcare, Forchheim, Germany (B.K.)
| | - Aleksander Kosmala
- From the Departments of Diagnostic and Interventional Radiology (B.P., A.K., A.M.W., A.H., T.G., T.A.B.) and Trauma, Hand, Plastic and Reconstructive Surgery (R.W., T.M.H.), University Hospital Würzburg, Oberdürrbacher Str 6, D-97080 Würzburg, Germany; Imaging and Therapy Division, Siemens Healthcare, Forchheim, Germany (B.K.)
| | - Andreas M. Weng
- From the Departments of Diagnostic and Interventional Radiology (B.P., A.K., A.M.W., A.H., T.G., T.A.B.) and Trauma, Hand, Plastic and Reconstructive Surgery (R.W., T.M.H.), University Hospital Würzburg, Oberdürrbacher Str 6, D-97080 Würzburg, Germany; Imaging and Therapy Division, Siemens Healthcare, Forchheim, Germany (B.K.)
| | - Bernhard Krauss
- From the Departments of Diagnostic and Interventional Radiology (B.P., A.K., A.M.W., A.H., T.G., T.A.B.) and Trauma, Hand, Plastic and Reconstructive Surgery (R.W., T.M.H.), University Hospital Würzburg, Oberdürrbacher Str 6, D-97080 Würzburg, Germany; Imaging and Therapy Division, Siemens Healthcare, Forchheim, Germany (B.K.)
| | - Anke Heidemeier
- From the Departments of Diagnostic and Interventional Radiology (B.P., A.K., A.M.W., A.H., T.G., T.A.B.) and Trauma, Hand, Plastic and Reconstructive Surgery (R.W., T.M.H.), University Hospital Würzburg, Oberdürrbacher Str 6, D-97080 Würzburg, Germany; Imaging and Therapy Division, Siemens Healthcare, Forchheim, Germany (B.K.)
| | - Richard Wagner
- From the Departments of Diagnostic and Interventional Radiology (B.P., A.K., A.M.W., A.H., T.G., T.A.B.) and Trauma, Hand, Plastic and Reconstructive Surgery (R.W., T.M.H.), University Hospital Würzburg, Oberdürrbacher Str 6, D-97080 Würzburg, Germany; Imaging and Therapy Division, Siemens Healthcare, Forchheim, Germany (B.K.)
| | - Timo M. Heintel
- From the Departments of Diagnostic and Interventional Radiology (B.P., A.K., A.M.W., A.H., T.G., T.A.B.) and Trauma, Hand, Plastic and Reconstructive Surgery (R.W., T.M.H.), University Hospital Würzburg, Oberdürrbacher Str 6, D-97080 Würzburg, Germany; Imaging and Therapy Division, Siemens Healthcare, Forchheim, Germany (B.K.)
| | - Tobias Gassenmaier
- From the Departments of Diagnostic and Interventional Radiology (B.P., A.K., A.M.W., A.H., T.G., T.A.B.) and Trauma, Hand, Plastic and Reconstructive Surgery (R.W., T.M.H.), University Hospital Würzburg, Oberdürrbacher Str 6, D-97080 Würzburg, Germany; Imaging and Therapy Division, Siemens Healthcare, Forchheim, Germany (B.K.)
| | - Thorsten A. Bley
- From the Departments of Diagnostic and Interventional Radiology (B.P., A.K., A.M.W., A.H., T.G., T.A.B.) and Trauma, Hand, Plastic and Reconstructive Surgery (R.W., T.M.H.), University Hospital Würzburg, Oberdürrbacher Str 6, D-97080 Würzburg, Germany; Imaging and Therapy Division, Siemens Healthcare, Forchheim, Germany (B.K.)
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Bongers MN, Schabel C, Krauss B, Claussen CD, Nikolaou K, Thomas C. Potential of gadolinium as contrast material in second generation dual energy computed tomography – An ex vivo phantom study. Clin Imaging 2017; 43:74-79. [DOI: 10.1016/j.clinimag.2017.02.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2016] [Revised: 01/16/2017] [Accepted: 02/17/2017] [Indexed: 11/26/2022]
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Gutjahr R, Polster C, Henning A, Kappler S, Leng S, McCollough CH, Sedlmair MU, Schmidt B, Krauss B, Flohr TG. Dual Energy CT Kidney Stone Differentiation in Photon Counting Computed Tomography. Proc SPIE Int Soc Opt Eng 2017; 10132:1013237. [PMID: 28943700 PMCID: PMC5607022 DOI: 10.1117/12.2252021] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
This study evaluates the capabilities of a whole-body photon counting CT system to differentiate between four common kidney stone materials, namely uric acid (UA), calcium oxalate monohydrate (COM), cystine (CYS),and apatite (APA) ex vivo. Two different x-ray spectra (120 kV and 140 kV) were applied and two acquisition modes were investigated; The macro-mode generates two energy threshold based image-volumes and two energy bin based image-volumes. In the chesspattern-mode, however, four energy thresholds are applied. A virtual low energy image, as well as a virtual high energy image are derived from initial threshold-based images, while considering their statistically correlated nature. The energy bin based images of the macro-mode, as well as the virtual low and high energy image of the chesspattern-mode serve as input for our dual energy evaluation. The dual energy ratio of the individually segmented kidney stones were utilized to quantify the discriminability of the different materials. The dual energy ratios of the two acquisition modes showed high correlation for both applied spectra. Wilcoxon-rank sum tests and the evaluation of the area under the receiver operating characteristics curves suggest that the UA kidney stones are best differentiable from all other materials (AUC = 1.0), followed by CYS (AUC ≈ 0.9 compared against COM and APA). COM and APA, however, are hardly distinguishable (AUC between 0.63 and 0.76). The results hold true for the measurements of both spectra and both acquisition modes.
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Affiliation(s)
- R Gutjahr
- CAMP, Technical University of Munich, Garching (Munich), Germany
- Siemens Healthcare GmbH, Forchheim, Germany
| | - C Polster
- Siemens Healthcare GmbH, Forchheim, Germany
- Institute of Clinical Radiology, Ludwig-Maximilians-University Hospital, Munich, Germany
| | - A Henning
- Siemens Healthcare GmbH, Forchheim, Germany
| | - S Kappler
- Siemens Healthcare GmbH, Forchheim, Germany
| | - S Leng
- Department of Radiology, Mayo Clinic, Rochester MN, United States of America
| | - C H McCollough
- Department of Radiology, Mayo Clinic, Rochester MN, United States of America
| | | | - B Schmidt
- Siemens Healthcare GmbH, Forchheim, Germany
| | - B Krauss
- Siemens Healthcare GmbH, Forchheim, Germany
| | - T G Flohr
- Siemens Healthcare GmbH, Forchheim, Germany
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Sandfort V, Palanisamy S, Symons R, Pourmorteza A, Ahlman MA, Rice K, Thomas T, Davies-Venn C, Krauss B, Kwan A, Pandey A, Zimmerman SL, Bluemke DA. Optimized energy of spectral CT for infarct imaging: Experimental validation with human validation. J Cardiovasc Comput Tomogr 2017; 11:171-178. [PMID: 28229910 DOI: 10.1016/j.jcct.2017.02.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/23/2017] [Revised: 02/03/2017] [Accepted: 02/07/2017] [Indexed: 10/20/2022]
Abstract
OBJECTIVES Late contrast enhancement visualizes myocardial infarction, but the contrast to noise ratio (CNR) is low using conventional CT. The aim of this study was to determine if spectral CT can improve imaging of myocardial infarction. MATERIALS AND METHODS A canine model of myocardial infarction was produced in 8 animals (90-min occlusion, reperfusion). Later, imaging was performed after contrast injection using CT at 90 kVp/150 kVpSn. The following reconstructions were evaluated: Single energy 90 kVp, mixed, iodine map, multiple monoenergetic conventional and monoenergetic noise optimized reconstructions. Regions of interest were measured in infarct and remote regions to calculate contrast to noise ratio (CNR) and Bhattacharya distance (a metric of the differentiation between regions). Blinded assessment of image quality was performed. The same reconstruction methods were applied to CT scans of four patients with known infarcts. RESULTS For animal studies, the highest CNR for infarct vs. myocardium was achieved in the lowest keV (40 keV) VMo images (CNR 4.42, IQR 3.64-5.53), which was superior to 90 kVp, mixed and iodine map (p = 0.008, p = 0.002, p < 0.001, respectively). Compared to 90 kVp and iodine map, the 40 keV VMo reconstructions showed significantly higher histogram separation (p = 0.042 and p < 0.0001, respectively). The VMo reconstructions showed the highest rate of excellent quality scores. A similar pattern was seen in human studies, with CNRs for infarct maximized at the lowest keV optimized reconstruction (CNR 4.44, IQR 2.86-5.94). CONCLUSIONS Dual energy in conjunction with noise-optimized monoenergetic post-processing improves CNR of myocardial infarct delineation by approximately 20-25%.
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Affiliation(s)
- Veit Sandfort
- Radiology and Imaging Sciences - National Institutes of Health Clinical Center, Bethesda, MD, USA
| | - Srikanth Palanisamy
- Radiology and Imaging Sciences - National Institutes of Health Clinical Center, Bethesda, MD, USA
| | - Rolf Symons
- Radiology and Imaging Sciences - National Institutes of Health Clinical Center, Bethesda, MD, USA
| | - Amir Pourmorteza
- Radiology and Imaging Sciences - National Institutes of Health Clinical Center, Bethesda, MD, USA
| | - Mark A Ahlman
- Radiology and Imaging Sciences - National Institutes of Health Clinical Center, Bethesda, MD, USA
| | - Kelly Rice
- ORS Division of Veterinary Resources, National Institutes of Health, Bethesda, MD, USA
| | - Tom Thomas
- ORS Division of Veterinary Resources, National Institutes of Health, Bethesda, MD, USA
| | - Cynthia Davies-Venn
- Radiology and Imaging Sciences - National Institutes of Health Clinical Center, Bethesda, MD, USA
| | | | - Alan Kwan
- Johns Hopkins University, Baltimore, MD, USA
| | | | | | - David A Bluemke
- Radiology and Imaging Sciences - National Institutes of Health Clinical Center, Bethesda, MD, USA.
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Krauss B, Apkarian A. Group Average Activation Maps of Functional MRI: Methodology of Identifying Group Brain Areas Activated during Painful Thermal Stimuli, Motor and Vibrotactile Tasks in Humans. ACTA ACUST UNITED AC 2016. [DOI: 10.1177/19714009980110s239] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- B. Krauss
- Department of Neurosurgery, SUNY Health Science Center; Syracuse, NY
| | - A.V. Apkarian
- Department of Neurosurgery, SUNY Health Science Center; Syracuse, NY
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Michalak G, Halaweish A, Krauss B, Fletcher J, McCollough C. SU-F-J-75: Accuracy and Stability of Electron Density Measurements Across Patient Size Using Dual Energy CT. Med Phys 2016. [DOI: 10.1118/1.4955983] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Gordic S, Puippe GD, Krauss B, Klotz E, Desbiolles L, Lesurtel M, Müllhaupt B, Pfammatter T, Alkadhi H. Correlation between Dual-Energy and Perfusion CT in Patients with Hepatocellular Carcinoma. Radiology 2016; 280:78-87. [PMID: 26824712 DOI: 10.1148/radiol.2015151560] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Purpose To develop a dual-energy contrast media-enhanced computed tomographic (CT) protocol by using time-attenuation curves from previously acquired perfusion CT data and to evaluate prospectively the relationship between iodine enhancement metrics at dual-energy CT and perfusion CT parameters in patients with hepatocellular carcinoma (HCC). Materials and Methods Institutional review board and local ethics committee approval and written informed consent were obtained. The retrospective part of this study included the development of a dual-energy CT contrast-enhanced protocol to evaluate peak arterial enhancement of HCC in the liver on the basis of time-attenuation curves from previously acquired perfusion CT data in 20 patients. The prospective part of the study consisted of an intraindividual comparison of dual-energy CT and perfusion CT data in another 20 consecutive patients with HCC. Iodine density and iodine ratio (iodine attenuation of the lesion divided by iodine attenuation in the aorta) from dual-energy CT and arterial perfusion (AP), portal venous perfusion, and total perfusion (TP) from perfusion CT were compared. Pearson R and linear correlation coefficients were calculated for AP and iodine density, AP and iodine ratio, TP and iodine density, and TP and iodine ratio. Results The dual-energy CT protocol consisted of bolus tracking in the abdominal aorta (threshold, 150 HU; scan delay, 9 seconds). The strongest intraindividual correlations in HCCs were found between iodine density and AP (r = 0.75, P = .0001). Moderate correlations were found between iodine ratio and AP (r = 0.50, P = .023) and between iodine density and TP (r = 0.56, P = .011). No further significant correlations were found. The volume CT dose index (11.4 mGy) and dose-length product (228.0 mGy · cm) of dual-energy CT was lower than those of the arterial phase of perfusion CT (36.1 mGy and 682.3 mGy · cm, respectively). Conclusion A contrast-enhanced dual-energy CT protocol developed by using time-attenuation curves from previously acquired perfusion CT data sets in patients with HCC could show good correlation between iodine density from dual-energy CT with AP from perfusion CT. (©) RSNA, 2016.
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Affiliation(s)
- Sonja Gordic
- From the Institute of Diagnostic and Interventional Radiology (S.G., G.P., T.P., H.A.), Department of Surgery, Swiss Hepato-Pancreatico-Biliary and Transplantation Center (M.L.), and Department of Hepatology and Gastroenterology (B.M.), University Hospital Zurich, University of Zurich, Raemistrasse 100, Zurich 8091, Switzerland; Computed Tomography Division, Siemens Healthcare, Forchheim, Germany (B.K., E.K.); and Division of Radiology and Nuclear Medicine, Kantonsspital St. Gallen, St. Gallen, Switzerland (L.D.)
| | - Gilbert D Puippe
- From the Institute of Diagnostic and Interventional Radiology (S.G., G.P., T.P., H.A.), Department of Surgery, Swiss Hepato-Pancreatico-Biliary and Transplantation Center (M.L.), and Department of Hepatology and Gastroenterology (B.M.), University Hospital Zurich, University of Zurich, Raemistrasse 100, Zurich 8091, Switzerland; Computed Tomography Division, Siemens Healthcare, Forchheim, Germany (B.K., E.K.); and Division of Radiology and Nuclear Medicine, Kantonsspital St. Gallen, St. Gallen, Switzerland (L.D.)
| | - Bernhard Krauss
- From the Institute of Diagnostic and Interventional Radiology (S.G., G.P., T.P., H.A.), Department of Surgery, Swiss Hepato-Pancreatico-Biliary and Transplantation Center (M.L.), and Department of Hepatology and Gastroenterology (B.M.), University Hospital Zurich, University of Zurich, Raemistrasse 100, Zurich 8091, Switzerland; Computed Tomography Division, Siemens Healthcare, Forchheim, Germany (B.K., E.K.); and Division of Radiology and Nuclear Medicine, Kantonsspital St. Gallen, St. Gallen, Switzerland (L.D.)
| | - Ernst Klotz
- From the Institute of Diagnostic and Interventional Radiology (S.G., G.P., T.P., H.A.), Department of Surgery, Swiss Hepato-Pancreatico-Biliary and Transplantation Center (M.L.), and Department of Hepatology and Gastroenterology (B.M.), University Hospital Zurich, University of Zurich, Raemistrasse 100, Zurich 8091, Switzerland; Computed Tomography Division, Siemens Healthcare, Forchheim, Germany (B.K., E.K.); and Division of Radiology and Nuclear Medicine, Kantonsspital St. Gallen, St. Gallen, Switzerland (L.D.)
| | - Lotus Desbiolles
- From the Institute of Diagnostic and Interventional Radiology (S.G., G.P., T.P., H.A.), Department of Surgery, Swiss Hepato-Pancreatico-Biliary and Transplantation Center (M.L.), and Department of Hepatology and Gastroenterology (B.M.), University Hospital Zurich, University of Zurich, Raemistrasse 100, Zurich 8091, Switzerland; Computed Tomography Division, Siemens Healthcare, Forchheim, Germany (B.K., E.K.); and Division of Radiology and Nuclear Medicine, Kantonsspital St. Gallen, St. Gallen, Switzerland (L.D.)
| | - Mickaël Lesurtel
- From the Institute of Diagnostic and Interventional Radiology (S.G., G.P., T.P., H.A.), Department of Surgery, Swiss Hepato-Pancreatico-Biliary and Transplantation Center (M.L.), and Department of Hepatology and Gastroenterology (B.M.), University Hospital Zurich, University of Zurich, Raemistrasse 100, Zurich 8091, Switzerland; Computed Tomography Division, Siemens Healthcare, Forchheim, Germany (B.K., E.K.); and Division of Radiology and Nuclear Medicine, Kantonsspital St. Gallen, St. Gallen, Switzerland (L.D.)
| | - Beat Müllhaupt
- From the Institute of Diagnostic and Interventional Radiology (S.G., G.P., T.P., H.A.), Department of Surgery, Swiss Hepato-Pancreatico-Biliary and Transplantation Center (M.L.), and Department of Hepatology and Gastroenterology (B.M.), University Hospital Zurich, University of Zurich, Raemistrasse 100, Zurich 8091, Switzerland; Computed Tomography Division, Siemens Healthcare, Forchheim, Germany (B.K., E.K.); and Division of Radiology and Nuclear Medicine, Kantonsspital St. Gallen, St. Gallen, Switzerland (L.D.)
| | - Thomas Pfammatter
- From the Institute of Diagnostic and Interventional Radiology (S.G., G.P., T.P., H.A.), Department of Surgery, Swiss Hepato-Pancreatico-Biliary and Transplantation Center (M.L.), and Department of Hepatology and Gastroenterology (B.M.), University Hospital Zurich, University of Zurich, Raemistrasse 100, Zurich 8091, Switzerland; Computed Tomography Division, Siemens Healthcare, Forchheim, Germany (B.K., E.K.); and Division of Radiology and Nuclear Medicine, Kantonsspital St. Gallen, St. Gallen, Switzerland (L.D.)
| | - Hatem Alkadhi
- From the Institute of Diagnostic and Interventional Radiology (S.G., G.P., T.P., H.A.), Department of Surgery, Swiss Hepato-Pancreatico-Biliary and Transplantation Center (M.L.), and Department of Hepatology and Gastroenterology (B.M.), University Hospital Zurich, University of Zurich, Raemistrasse 100, Zurich 8091, Switzerland; Computed Tomography Division, Siemens Healthcare, Forchheim, Germany (B.K., E.K.); and Division of Radiology and Nuclear Medicine, Kantonsspital St. Gallen, St. Gallen, Switzerland (L.D.)
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Gariani J, Cuvinciuc V, Courvoisier D, Krauss B, Mendes Pereira V, Sztajzel R, Lovblad KO, Vargas MI. Diagnosis of acute ischemia using dual energy CT after mechanical thrombectomy. J Neurointerv Surg 2015; 8:996-1000. [PMID: 26534867 DOI: 10.1136/neurintsurg-2015-011988] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2015] [Accepted: 10/12/2015] [Indexed: 11/04/2022]
Abstract
BACKGROUND AND PURPOSE To assess the performance of dual energy unenhanced CT in the detection of acute ischemia after mechanical thrombectomy. METHODS Retrospective study, approved by the local institutional review board, including all patients that underwent intra-arterial thrombectomy in our institution over a period of 2 years. The presence of acute ischemia and hemorrhage was evaluated by three readers. Sensitivity and specificity of the non-contrast CT weighted sum image (NCCT) and the virtual non-contrast reconstructed image (VNC) were estimated and compared using generalized estimating equations to account for the non-independence of regions in each patient. RESULTS 58 patients (27 women and 31 men; mean age 70.4 years) were included in the study, yielding 580 regions of interest. Sensitivity and specificity in detecting acute ischemia were higher for all readers when using VNC, with a significant increase in sensitivity for two readers (p<0.001 and 0.01) and a significant increase in specificity in one reader (p<0.001). Specificity in detecting hemorrhage was excellent for all readers. CONCLUSIONS Dual energy unenhanced CT VNC images were superior in the identification of acute ischemia in comparison with NCCT.
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Affiliation(s)
- Joanna Gariani
- Department of Radiology, Geneva University Hospitals, Geneva, Switzerland
| | - Victor Cuvinciuc
- Department of Neuroradiology, Geneva University Hospitals, Geneva, Switzerland
| | - Delphine Courvoisier
- Department of Clinical Epidemiology, Department of Health and Community Medicine, Geneva University Hospitals, Geneva, Switzerland
| | | | | | - Roman Sztajzel
- Department of Neurology, Geneva University Hospitals, Geneva, Switzerland
| | - Karl-Olof Lovblad
- Department of Neuroradiology, Geneva University Hospitals, Geneva, Switzerland
| | - Maria Isabel Vargas
- Department of Neuroradiology, Geneva University Hospitals, Geneva, Switzerland
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Bongers MN, Schabel C, Krauss B, Tsiflikas I, Ketelsen D, Mangold S, Claussen CD, Nikolaou K, Thomas C. Noise-optimized virtual monoenergetic images and iodine maps for the detection of venous thrombosis in second-generation dual-energy CT (DECT): an ex vivo phantom study. Eur Radiol 2014; 25:1655-64. [PMID: 25528670 DOI: 10.1007/s00330-014-3544-8] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2014] [Revised: 10/15/2014] [Accepted: 11/25/2014] [Indexed: 12/25/2022]
Abstract
AIMS AND OBJECTIVES Deep venous thrombosis (DVT) can be difficult to detect using CT due to poor and heterogeneous contrast. Dual-energy CT (DECT) allows iodine contrast optimization using noise-optimized monoenergetic extrapolations (MEIs) and iodine maps (IMs). Our aim was to assess whether MEI and IM could improve the delineation of thrombotic material within iodine-enhanced blood compared to single-energy CT (SECT). MATERIALS AND METHODS Six vessel phantoms, including human thrombus and contrast media-enhanced blood and one phantom without contrast, were placed in an attenuation phantom and scanned with DECT 100/140 kV and SECT 120 kV. IM, virtual non-contrast images (VNC), mixed images, and MEI were calculated. Attenuation of thrombi and blood were measured. Contrast and contrast-to-noise-ratios (CNRs) were calculated and compared among IM, VNC, mixed images, MEI, and SECT using paired t tests. RESULTS MEI40keV and IM showed significantly higher contrast and CNR than SE120kV from high to intermediate iodine concentrations (contrast:pMEI40keV < 0.002,pIM < 0.005;CNR:pMEI40keV < 0.002,pIM < 0.004). At low iodine concentrations, MEI190keV and VNC images showed significantly higher contrast and CNR than SE120kV with inverted contrasts (contrast:pMEI190keV < 0.008,pVNC < 0.002;CNR:pMEI190keV < 0.003,pVNC < 0.002). CONCLUSIONS Noise-optimized MEI and IM provide significantly higher contrast and CNR in the delineation of thrombosis compared to SECT, which may facilitate the detection of DVT in difficult cases. KEY POINTS • Poor contrast makes it difficult to detect thrombosis in CT. • Dual-energy-CT allows contrast optimization using monoenergetic extrapolations (MEI) and iodine maps (IM). • Noise-optimized-MEI and IM are significantly superior to single-energy-CT in delineation of thrombosis. • Noise-optimized-MEI and IM may facilitate the detection of deep vein thrombosis.
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Affiliation(s)
- Malte N Bongers
- Department of Diagnostic and Interventional Radiology, University Hospital of Tübingen, Hoppe-Seyler-Strasse 3, 72076, Tübingen, Germany
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Müller-Wille R, Borgmann T, Wohlgemuth WA, Zeman F, Pfister K, Jung EM, Heiss P, Schreyer AG, Krauss B, Stroszczynski C, Dornia C. Dual-energy computed tomography after endovascular aortic aneurysm repair: The role of hard plaque imaging for endoleak detection. Eur Radiol 2014; 24:2449-57. [DOI: 10.1007/s00330-014-3266-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2013] [Revised: 05/16/2014] [Accepted: 05/23/2014] [Indexed: 10/25/2022]
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Toepker M, Kuehas F, Kienzl D, Herwig R, Spazierer E, Krauss B, Weber M, Seitz C, Ringl H. Dual Energy Computerized Tomography with a Split Bolus—A 1-Stop Shop for Patients with Suspected Urinary Stones? J Urol 2014; 191:792-7. [DOI: 10.1016/j.juro.2013.10.057] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/15/2013] [Indexed: 10/26/2022]
Affiliation(s)
- Michael Toepker
- Department of Radiology, Medical University Vienna, Vienna General Hospital, Vienna, Austria
| | - Franklin Kuehas
- Department of Urology, Medical University Vienna, Vienna General Hospital, Vienna, Austria
| | - Daniela Kienzl
- Department of Radiology, Medical University Vienna, Vienna General Hospital, Vienna, Austria
| | - Ralf Herwig
- Department of Urology, Medical University Vienna, Vienna General Hospital, Vienna, Austria
| | - Elisa Spazierer
- Department of Radiology, Medical University Vienna, Vienna General Hospital, Vienna, Austria
| | | | - Michael Weber
- Department of Radiology, Medical University Vienna, Vienna General Hospital, Vienna, Austria
| | - Christian Seitz
- Department of Urology, Medical University Vienna, Vienna General Hospital, Vienna, Austria
| | - Helmut Ringl
- Department of Radiology, Medical University Vienna, Vienna General Hospital, Vienna, Austria
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Hünemohr N, Krauss B, Tremmel C, Ackermann B, Jäkel O, Greilich S. Experimental verification of ion stopping power prediction from dual energy CT data in tissue surrogates. Phys Med Biol 2013; 59:83-96. [DOI: 10.1088/0031-9155/59/1/83] [Citation(s) in RCA: 128] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Melzer R, Pauli C, Treumann T, Krauss B. Gout tophus detection-a comparison of dual-energy CT (DECT) and histology. Semin Arthritis Rheum 2013; 43:662-5. [PMID: 24332008 DOI: 10.1016/j.semarthrit.2013.11.002] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2013] [Revised: 11/05/2013] [Accepted: 11/07/2013] [Indexed: 11/24/2022]
Abstract
OBJECTIVES To compare dual-energy CT images (DECT) directly with gold standard histology. METHODS A 85-year-old woman with chronic recurrent gouty arthritis and macroscopically visible tophi was assessed with DECT-scans of her feet. When she died 7 days later, three tophi in different regions and in different tissues of her left foot were processed for histological examination. RESULTS Of the selected tophi, two were almost completely missed by the color-coding DECT sequences. The tophi remained in most of their volume below the detection threshold value of 150HU (default value). CONCLUSIONS It could be demonstrated that DECT only highlights the dense tophi (corresponding of approximately 15-20vol% urate in the tophus). Less dense tophi, despite considerable size, will be missed in the color-coded images.
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Affiliation(s)
- Ralph Melzer
- Clinic of Rheumatology, Luzerner Kantonsspital, 6000 Lucerne 16, Switzerland.
| | - Chantal Pauli
- Institute of Pathology, Luzerner Kantonsspital, Lucerne, Switzerland
| | - Thomas Treumann
- Institute of Radiology, Luzerner Kantonsspital, Lucerne, Switzerland
| | - Bernhard Krauss
- Imaging & Therapy Division, Healthcare Sector, Siemens AG, Forchheim, Germany
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Krauss B, Andolfatto G, Deitch K, Piela N, Damiron K, Monuteaux M. Apnea Characteristics and Predictors During Procedural Sedation and Analgesia. Ann Emerg Med 2013. [DOI: 10.1016/j.annemergmed.2013.07.178] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Hünemohr N, Krauss B, Dinkel J, Gillmann C, Ackermann B, Jäkel O, Greilich S. Ion range estimation by using dual energy computed tomography. Z Med Phys 2013; 23:300-13. [PMID: 23597413 DOI: 10.1016/j.zemedi.2013.03.001] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2012] [Revised: 03/05/2013] [Accepted: 03/06/2013] [Indexed: 11/28/2022]
Abstract
Inaccurate conversion of CT data to water-equivalent path length (WEPL) is one of the most important uncertainty sources in ion treatment planning. Dual energy CT (DECT) imaging might help to reduce CT number ambiguities with the additional information. In our study we scanned a series of materials (tissue substitutes, aluminum, PMMA, and other polymers) in the dual source scanner (Siemens Somatom Definition Flash). Based on the 80kVp/140SnkVp dual energy images, the electron densities ϱe and effective atomic numbers Zeff were calculated. We introduced a new lookup table that translates the ϱe to the WEPL. The WEPL residuals from the calibration were significantly reduced for the investigated tissue surrogates compared to the empirical Hounsfield-look-up table (single energy CT imaging) from (-1.0±1.8)% to (0.1±0.7)% and for non-tissue equivalent PMMA from -7.8% to -1.0%. To assess the benefit of the new DECT calibration, we conducted a treatment planning study for three different idealized cases based on tissue surrogates and PMMA. The DECT calibration yielded a significantly higher target coverage in tissue surrogates and phantom material (i.e. PMMA cylinder, mean target coverage improved from 62% to 98%). To verify the DECT calibration for real tissue, ion ranges through a frozen pig head were measured and compared to predictions calculated by the standard single energy CT calibration and the novel DECT calibration. By using this method, an improvement of ion range estimation from -2.1% water-equivalent thickness deviation (single energy CT) to 0.3% (DECT) was achieved. If one excludes raypaths located on the edge of the sample accompanied with high uncertainties, no significant difference could be observed.
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Affiliation(s)
- Nora Hünemohr
- Medical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Heidelberg, Germany.
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Ascenti G, Mileto A, Krauss B, Gaeta M, Blandino A, Scribano E, Settineri N, Mazziotti S. Distinguishing enhancing from nonenhancing renal masses with dual-source dual-energy CT: iodine quantification versus standard enhancement measurements. Eur Radiol 2013; 23:2288-95. [DOI: 10.1007/s00330-013-2811-4] [Citation(s) in RCA: 107] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2012] [Revised: 01/20/2013] [Accepted: 01/24/2013] [Indexed: 01/03/2023]
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Korn A, Fenchel M, Bender B, Danz S, Thomas C, Ketelsen D, Claussen CD, Moonis G, Krauss B, Heuschmid M, Ernemann U, Brodoefel H. High-pitch dual-source CT angiography of supra-aortic arteries: assessment of image quality and radiation dose. Neuroradiology 2012; 55:423-30. [PMID: 23223824 DOI: 10.1007/s00234-012-1120-y] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2012] [Accepted: 11/13/2012] [Indexed: 01/31/2023]
Abstract
INTRODUCTION High-pitch CT angiography (CTA) is a recent innovation that allows significant shortening of scan time with volume coverage of 43 mm per second. The aim of our study was to assess this technique in CTA of the head and neck. METHODS CTA of supra-aortic arteries was performed in 50 patients using two acquisition protocols: conventional single-source 64-slice (pitch 1.2) and high-pitch dual-source 128-slice CT (pitch 3.2). Subjective and objective image quality of supra-aortic vessel ostia as well as intra- and extra-cranial segments was retrospectively assessed by blinded readers and radiation dose compared between the two protocols. RESULTS Conventional and high-pitch CTA achieved comparable signal-to-noise ratios in arterial (54.3 ± 16.5 versus 57.3 ± 14.8; p = 0.50) and venous segments (15.8 ± 6.7 versus 18.9 ± 8.9; p = 0.21). High-pitch scanning was, however, associated with sharper delineation of vessel contours and image quality significantly improved at the level of supra-aortic vessel ostia (p < 0.0001) as well as along the brachiocephalic trunk (p < 0.0001), the subclavian arteries (p < 0.0001), proximal common carotid arteries (p = 0.01), and vertebral V1 segments (p < 0.0001). Using the high-pitch mode, the dose-length product was reduced by about 35% (218.2 ± 30 versus 141.8 ± 20 mGy × cm). CONCLUSIONS Due to elimination of transmitted cardiac motion, high-pitch CTA of the neck improves image quality in the proximity of the aortic arch while significantly lowering radiation dose. The technique thus qualifies as a promising alternative to conventional spiral CTA and may be particularly useful for identification of ostial stenosis.
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Affiliation(s)
- A Korn
- Department of Diagnostic und Interventional Neuroradiology, Hoppe-Seyler-Strasse 3, 72076 Tuebingen, Germany
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Tremmel C, Huenemohr N, Krauss B, Schlemmer H, Jaekel O, Greilich S. Dual Energy CT: Treatment Planning for Proton and Ion Radiation Therapy Beyond Standard Tissue Composition. Int J Radiat Oncol Biol Phys 2012. [DOI: 10.1016/j.ijrobp.2012.07.146] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Johnson TRC, Himsl I, Hellerhoff K, Mayr D, Rjosk-Dendorfer D, Ditsch N, Krauss B, Friese K, Reiser MF, Lenhard MS. Dual-energy CT for the evaluation of silicone breast implants. Eur Radiol 2012; 23:991-6. [PMID: 23064715 DOI: 10.1007/s00330-012-2667-z] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2012] [Revised: 08/28/2012] [Accepted: 09/08/2012] [Indexed: 01/01/2023]
Abstract
OBJECTIVE The evaluation of breast implants for rupture is currently the domain of ultrasound and MRI, while mammography is of very limited diagnostic value. Recently, specific visualisation of silicone has become feasible using dual-energy CT. Our objective was to evaluate whether it is feasible to identify silicone in breast implants by dual-energy CT and to reliably diagnose or rule out ruptures. METHODS Seven silicone breast implant specimens were examined on dual-source CT at 100- and 140-kV tube potential with a 0.8-mm tin filter (collimation 128 × 0.6 mm, current-time products 165 and 140 mAsref with modulation, rotation time 0.28 s, pitch 0.55). Two patients scheduled for implant removal or replacement were examined with identical parameters. RESULTS The silicone of the implant specimens showed a strong dual-energy signal. In one patient, both implants were intact, while a rupture was identified in the other patient. Ultrasound, MRI, surgical findings and histology confirmed the dual-energy CT diagnosis. CONCLUSION Dual-energy CT may serve as an alternative technique for speedy evaluation of silicone breast implants. Specific clinical studies are required to determine the diagnostic accuracy and define indications for this technique.
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Affiliation(s)
- Thorsten R C Johnson
- Department of Clinical Radiology, University of Munich-Grosshadern Campus, Marchioninistr. 15, 81377 Munich, Germany.
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Ascenti G, Krauss B, Mazziotti S, Mileto A, Settineri N, Vinci S, Donato R, Gaeta M. Dual-energy computed tomography (DECT) in renal masses: nonlinear versus linear blending. Acad Radiol 2012; 19:1186-93. [PMID: 22818789 DOI: 10.1016/j.acra.2012.05.010] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2012] [Revised: 05/08/2012] [Accepted: 05/08/2012] [Indexed: 11/15/2022]
Abstract
RATIONAL AND OBJECTIVES To investigate whether a nonlinear-blending algorithm improves tumor conspicuity and image quality in the evaluation of renal masses at dual-energy computed tomography (DECT) during nephrographic phase of enhancement. MATERIALS AND METHODS The Institutional Review Board approved this retrospective study from archival material from patients consenting to the use of medical records for research purposes. A retrospective review of contrast-enhanced abdominal DECT scans in 45 patients (mean age, 59.5 years; range, 24-84 years) was performed. DECT data were reconstructed using nonlinear and linear blending. A region of interest was located within tumors and adjacent normal parenchyma; attenuation differences and contrast-to-noise ratios (CNRs) were calculated for renal masses on nonlinear- and linear-blended images. The two datasets were subjectively compared in terms of tumor detection and image quality. An exact Wilcoxon's matched pairs signed rank and marginal homogeneity tests were used to test whether differences in attenuation, CNR, and subjective assessment were greater using nonlinear blending. RESULTS The mean difference in attenuation for renal masses and adjacent portion of renal parenchyma was 138.4 Hounsfield units ± 28.9 SD using nonlinear blending, and 121.6 HU ± 18.0 SD using linear blending (P < .001). Mean CNR was 12.6 ± 2.5 SD using nonlinear blending, and 9.6 ± 2.2 SD using 0.3 linear-blended (P < .001). No significant difference in tumor detection was observed between the two algorithms. Image quality was significantly better (P < .001) using nonlinear blending. CONCLUSION Compared with standard linear blending, nonlinear-blending algorithm improves tumor conspicuity and image quality in renal masses at DECT evaluation during nephrographic phase of enhancement.
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Affiliation(s)
- Giorgio Ascenti
- Department of Radiological Sciences, Policlinico G. Martino, Via Consolare Valeria 1, 98125 Messina, Italy
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Mangold S, Thomas C, Fenchel M, Vuust M, Krauss B, Ketelsen D, Tsiflikas I, Claussen CD, Heuschmid M. Virtual Nonenhanced Dual-Energy CT Urography with Tin-Filter Technology: Determinants of Detection of Urinary Calculi in the Renal Collecting System. Radiology 2012; 264:119-25. [PMID: 22570506 DOI: 10.1148/radiol.12110851] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
- Stefanie Mangold
- Department of Diagnostic and Interventional Radiology, Eberhard-Karls-University Tuebingen, Hoppe-Seyler-Str. 3, 72076 Tuebingen, Germany
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Guggenberger R, Gnannt R, Hodler J, Krauss B, Wanner GA, Csuka E, Payne B, Frauenfelder T, Andreisek G, Alkadhi H. Diagnostic Performance of Dual-Energy CT for the Detection of Traumatic Bone Marrow Lesions in the Ankle: Comparison with MR Imaging. Radiology 2012; 264:164-73. [DOI: 10.1148/radiol.12112217] [Citation(s) in RCA: 111] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Kim SJ, Lim HK, Lee HY, Choi CG, Lee DH, Suh DC, Kim SM, Kim JK, Krauss B. Dual-energy CT in the evaluation of intracerebral hemorrhage of unknown origin: differentiation between tumor bleeding and pure hemorrhage. AJNR Am J Neuroradiol 2012; 33:865-72. [PMID: 22241388 DOI: 10.3174/ajnr.a2890] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE Detection of underlying tumor in patients with unknown-origin acute ICH may be difficult because acute hematoma may mask enhancement of tumor on postcontrast CT. We intended to investigate the clinical utility of DECT in differentiating tumor bleeding from pure ICH. MATERIALS AND METHODS Using a dual-source CT scanner, we obtained TNC single-energy and postcontrast DECT scans for 56 patients with unknown-origin spontaneous ICH. From the 2 sets of postcontrast DECT images obtained with different tube energy, EA (equivalent to conventional postcontrast CT), VNC, color-coded iodine overlay, fusion images of iodine overlay and VNC images were produced. The diagnostic performances of fusion, EA, and combined EA and TNC images for detecting underlying tumors were compared. RESULTS Of the 56 patients, 17 had primary or metastatic tumors (18 lesions) and 39 had nontumorous ICH. The sensitivities of fusion, EA, and combined EA and TNC images for detecting brain tumors were 94.4%, 61.1%, and 66.7%, respectively, and their specificities were 97.4%, 92.3%, and 89.7%, respectively. The areas under the ROC curves were 0.964, 0.786, and 0.842, respectively. Overall, the diagnostic performance of fusion images was significantly superior to EA (P = .006) and combined EA and TNC (P = .011) images. CONCLUSIONS DECT may be useful in detecting underlying tumors in patients with unknown-origin ICH.
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Affiliation(s)
- S J Kim
- Department of Radiology and Research Institute of Radiology, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea.
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Leng S, Grant K, Vrtiska T, Krauss B, Shiung M, Hansen S, Wang J, Duan X, McCollough C. 1945 FEASIBILITY OF DISCRIMINATING URIC ACID FROM NON-URIC ACID RENAL STONES USING A SINGLE-SOURCE CT SCANNER AND 3D ANATOMIC REGISTRATION IN VITRO AND IN VIVO STUDIES. J Urol 2012. [DOI: 10.1016/j.juro.2012.02.2103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Honda N, Osada H, Watanabe W, Nakayama M, Nishimura K, Krauss B, Otani K. Imaging of Ventilation with Dual-Energy CT during Breath Hold after Single Vital-Capacity Inspiration of Stable Xenon. Radiology 2012; 262:262-8. [DOI: 10.1148/radiol.11110569] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Paul J, Banckwitz R, Krauss B, Vogl TJ, Maentele W, Bauer RW. Estimation and comparison of effective dose (E) in standard chest CT by organ dose measurements and dose-length-product methods and assessment of the influence of CT tube potential (energy dependency) on effective dose in a dual-source CT. Eur J Radiol 2011; 81:e507-12. [PMID: 21703793 DOI: 10.1016/j.ejrad.2011.06.006] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2011] [Accepted: 06/01/2011] [Indexed: 10/24/2022]
Abstract
PURPOSE To determine effective dose (E) during standard chest CT using an organ dose-based and a dose-length-product-based (DLP) approach for four different scan protocols including high-pitch and dual-energy in a dual-source CT scanner of the second generation. MATERIALS AND METHODS Organ doses were measured with thermo luminescence dosimeters (TLD) in an anthropomorphic male adult phantom. Further, DLP-based dose estimates were performed by using the standard 0.014mSv/mGycm conversion coefficient k. Examinations were performed on a dual-source CT system (Somatom Definition Flash, Siemens). Four scan protocols were investigated: (1) single-source 120kV, (2) single-source 100kV, (3) high-pitch 120kV, and (4) dual-energy with 100/Sn140kV with equivalent CTDIvol and no automated tube current modulation. E was then determined following recommendations of ICRP publication 103 and 60 and specific k values were derived. RESULTS DLP-based estimates differed by 4.5-16.56% and 5.2-15.8% relatively to ICRP 60 and 103, respectively. The derived k factors calculated from TLD measurements were 0.0148, 0.015, 0.0166, and 0.0148 for protocol 1, 2, 3 and 4, respectively. Effective dose estimations by ICRP 103 and 60 for single-energy and dual-energy protocols show a difference of less than 0.04mSv. CONCLUSION Estimates of E based on DLP work equally well for single-energy, high-pitch and dual-energy CT examinations. The tube potential definitely affects effective dose in a substantial way. Effective dose estimations by ICRP 103 and 60 for both single-energy and dual-energy examinations differ not more than 0.04mSv.
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Affiliation(s)
- Jijo Paul
- Department of Diagnostic Radiology, Goethe University-Frankfurt am Main, Theodor-Stern-Kai 7, 60590 Frankfurt am Main, Germany.
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Mangold S, Thomas C, Fenchel M, Vuust M, Krauss B, Ketelsen D, Tsiflikas I, Claussen CD, Heuschmid M. Virtuell-native Dual Energy-CT-Urographie mit Zinn-Filter-Technologie: Detektierbarkeit von Harnsteinen in vivo im Vergleich mit nativer CT Urographie. ROFO-FORTSCHR RONTG 2011. [DOI: 10.1055/s-0031-1279480] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Pache G, Krauss B, Strohm P, Blanke P, Bulla S, Schäfer AO, Baumann T, Langer M. Machbarkeit der Detektion posttraumatischer Knochenmarksläsionen mittels Dual-Energy CT basierter “virtual noncalcium technique“. ROFO-FORTSCHR RONTG 2011. [DOI: 10.1055/s-0031-1279302] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Knöss N, Hoffmann B, Krauss B, Heller M, Biederer J. Dual energy computed tomography of lung nodules: differentiation of iodine and calcium in artificial pulmonary nodules in vitro. Eur J Radiol 2010; 80:e516-9. [PMID: 21112712 DOI: 10.1016/j.ejrad.2010.11.001] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2010] [Accepted: 11/03/2010] [Indexed: 11/30/2022]
Abstract
BACKGROUND Iodine enhancement is a marker for malignancy in pulmonary nodules. The purpose of this in vitro study was to assess whether dual energy computed tomography (DECT) can be used to detect iodine and to distinguish iodine from disperse calcifications in artificial pulmonary nodules. MATERIALS AND METHODS Small, medium, and large artificial nodules (n=54), with increasing concentrations of iodine or calcium corresponding to an increase in Hounsfield Units (HU) of 15, 30, 45, and 90 at 120 kV, were scanned in a chest phantom with DECT at 80 and 140 kV. Attenuation values of each nodule were measured using semi-automated volumetric analysis. The mean DE ratio with 95% confidence intervals (CI) was calculated for each nodule. RESULTS The mean maximum diameter of the 18 small nodules was 12 mm (standard deviation: 0.4), 16 mm (0.4) for the 18 medium nodules, and 30 mm (1.1) for the 18 large nodules. There was no overlap of 95% CI of DE ratios of iodine and calcium in nodules≥16 mm. In nodules<16 mm, there was an overlap of DE ratios in low contrast lesions. CONCLUSION DECT can distinguish iodine from calcium in artificial nodules≥16 mm in vitro. In smaller lesions, a clear differentiation is not possible.
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Affiliation(s)
- Naomi Knöss
- Department of Radiology, University Hospital Schleswig-Holstein, Campus Kiel, Germany.
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Thomas C, Korn A, Krauss B, Ketelsen D, Tsiflikas I, Reimann A, Brodoefel H, Claussen C, Kopp A, Ernemann U, Heuschmid M. Automatic bone and plaque removal using dual energy CT for head and neck angiography: Feasibility and initial performance evaluation. Eur J Radiol 2010; 76:61-7. [DOI: 10.1016/j.ejrad.2009.05.004] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2009] [Revised: 04/01/2009] [Accepted: 05/04/2009] [Indexed: 10/20/2022]
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Goo HW, Yang DH, Hong SJ, Yu J, Kim BJ, Seo JB, Chae EJ, Lee J, Krauss B. Xenon ventilation CT using dual-source and dual-energy technique in children with bronchiolitis obliterans: correlation of xenon and CT density values with pulmonary function test results. Pediatr Radiol 2010; 40:1490-7. [PMID: 20411254 DOI: 10.1007/s00247-010-1645-3] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/09/2009] [Revised: 01/17/2010] [Accepted: 02/07/2010] [Indexed: 11/30/2022]
Abstract
BACKGROUND Xenon ventilation CT using dual-source and dual-energy technique is a recently introduced, promising functional lung imaging method. To expand its clinical applications evidence of additional diagnostic value of xenon ventilation CT over conventional chest CT is required. OBJECTIVE To evaluate the usefulness of xenon ventilation CT using dual-source and dual-energy technique in children with bronchiolitis obliterans (BO). MATERIALS AND METHODS Seventeen children (age 7-18 years; 11 boys) with BO underwent xenon ventilation CT using dual-source and dual-energy technique. Xenon and CT density values were measured in normal and hyperlucent lung regions on CT and were compared between the two regions. Volumes of hyperlucent regions and ventilation defects were calculated with thresholds determined by visual and histogram-based analysis. Indexed volumes of hyperlucent lung regions and ventilation defects were correlated with pulmonary function test results. Effective doses of xenon CT were calculated. RESULTS Xenon (14.6 +/- 6.4 HU vs 26.1 +/- 6.5 HU; P < 0.001) and CT density (-892.8 +/- 25.4 HU vs -812.3 +/- 38.7 HU; P < 0.001) values were significantly lower in hyperlucent regions than in normal lung regions. Xenon and CT density values showed significant positive correlation for the entire lung in 16 children (gamma = 0.55 +/- 0.17, P < 0.001 or =0.017) and for hyperlucent regions in 13 children (gamma = 0.44 +/- 0.16, P < 0.001 or =0.001-0.019). Indexed volumes and volume percentages of hyperlucent lung regions and ventilation defects showed strong negative correlations with forced expiratory volume [FEV1, (gamma = -0.64--0.85, P <or= 0.006)], FEV1/forced vital capacity [FVC, (gamma = -0.63--0.84, P <or= 0.008), and forced midexpiratory flow rate [FEF(25-75), (gamma = -0.68--0.88, P <or= 0.002). Volume percentages of xenon ventilation defects (35.0 +/- 16.4%) were not significantly different from those of hyperlucent lung regions (38.2 +/- 18.6%). However, mismatches between the volume percentages were variable up to 21.4-33.3%. Mean effective dose of xenon CT was 1.9 +/- 0.5 mSv. CONCLUSION In addition to high-resolution anatomic information, xenon ventilation CT using dual-source and dual-energy technique demonstrates impaired regional ventilation and its heterogeneity accurately in children with BO without additional radiation exposure.
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Affiliation(s)
- Hyun Woo Goo
- Department of Radiology and Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
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