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Wehrse E, Klein L, Rotkopf LT, Wagner WL, Uhrig M, Heußel CP, Ziener CH, Delorme S, Heinze S, Kachelrieß M, Schlemmer HP, Sawall S. Photon-counting detectors in computed tomography: from quantum physics to clinical practice. Radiologe 2021; 61:1-10. [PMID: 33598788 DOI: 10.1007/s00117-021-00812-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/19/2021] [Indexed: 12/19/2022]
Abstract
Over the last decade, a fundamentally new type of computed tomography (CT) detectors has proved its superior capabilities in both physical and preclinical evaluations and is now approaching the stage of clinical practice. These detectors are able to discriminate single photons and quantify their energy and are hence called photon-counting detectors. Among the promising benefits of this technology are improved radiation dose efficiency, increased contrast-to-noise ratio, reduced metal artifacts, improved spatial resolution, simultaneous multi-energy acquisitions, and the prospect of multi-phase imaging within a single acquisition using multiple contrast agents. Taking the conventional energy-integrating detectors as a reference, the authors demonstrate the technical principles of this new technology and provide phantom and patient images acquired by a whole-body photon-counting CT. These images serve as a basis for discussing the potential future of clinical CT.
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Affiliation(s)
- E Wehrse
- Division of Radiology, German Cancer Research Center, Im Neuenheimer Feld 280, 69120, Heidelberg, Germany.
- Medical Faculty, Ruprecht-Karls-University Heidelberg, Heidelberg, Germany.
| | - L Klein
- Division of X-Ray Imaging and Computed Tomography, German Cancer Research Center, Heidelberg, Germany
| | - L T Rotkopf
- Division of Radiology, German Cancer Research Center, Im Neuenheimer Feld 280, 69120, Heidelberg, Germany
| | - W L Wagner
- Department of Diagnostic and Interventional Radiology, University Hospital Heidelberg, Heidelberg, Germany
- Translational Lung Research Center Heidelberg, German Center for Lung Research, Heidelberg, Germany
| | - M Uhrig
- Division of Radiology, German Cancer Research Center, Im Neuenheimer Feld 280, 69120, Heidelberg, Germany
| | - C P Heußel
- Department of Diagnostic and Interventional Radiology, University Hospital Heidelberg, Heidelberg, Germany
- Translational Lung Research Center Heidelberg, German Center for Lung Research, Heidelberg, Germany
- Diagnostic and Interventional Radiology with Nuclear Medicine, Thoraxklinik, University of Heidelberg, Heidelberg, Germany
| | - C H Ziener
- Division of Radiology, German Cancer Research Center, Im Neuenheimer Feld 280, 69120, Heidelberg, Germany
| | - S Delorme
- Division of Radiology, German Cancer Research Center, Im Neuenheimer Feld 280, 69120, Heidelberg, Germany
| | - S Heinze
- Institute of Forensic and Traffic Medicine, University Hospital Heidelberg, Voßstraße 2, 69115, Heidelberg, Germany
| | - M Kachelrieß
- Medical Faculty, Ruprecht-Karls-University Heidelberg, Heidelberg, Germany
- Division of X-Ray Imaging and Computed Tomography, German Cancer Research Center, Heidelberg, Germany
| | - H-P Schlemmer
- Division of Radiology, German Cancer Research Center, Im Neuenheimer Feld 280, 69120, Heidelberg, Germany
| | - S Sawall
- Medical Faculty, Ruprecht-Karls-University Heidelberg, Heidelberg, Germany
- Division of X-Ray Imaging and Computed Tomography, German Cancer Research Center, Heidelberg, Germany
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Wehrse E, Sawall S, Klein L, Glemser P, Delorme S, Schlemmer HP, Kachelrieß M, Uhrig M, Ziener CH, Rotkopf LT. Potential of ultra-high-resolution photon-counting CT of bone metastases: initial experiences in breast cancer patients. NPJ Breast Cancer 2021; 7:3. [PMID: 33398008 PMCID: PMC7782694 DOI: 10.1038/s41523-020-00207-3] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [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: 04/06/2020] [Accepted: 11/12/2020] [Indexed: 01/01/2023] Open
Abstract
Conventional CT scanners use energy-integrating detectors (EIDs). Photon-counting detector (PCD) computed tomography (CT) utilizes a CT detector technology based on smaller detector pixels capable of counting single photons and in addition discriminating their energy. Goal of this study was to explore the potential of higher spatial resolution for imaging of bone metastases. Four female patients with histologically confirmed breast cancer and bone metastases were included between July and October 2019. All patients underwent conventional EID CT scans followed by a high resolution non-contrast experimental PCD CT scan. Ultra-high resolution (UHR) reconstruction kernels were used to reconstruct axial slices with voxel sizes of 0.3 mm × 0.3 mm (inplane) × 1 mm (z-direction). Four radiologists blinded for patient identity assessed the images and compared the quality to conventional CT using a qualitative Likert scale. In this case series, we present images of bone metastases in breast cancer patients using an experimental PCD CT scanner and ultra-high-resolution kernels. A tendency to both a smaller inter-reader variability in the structural assessment of lesion sizes and in the readers' opinion to an improved visualization of lesion margins and content was observed. In conclusion, while further studies are warranted, PCD CT has a high potential for therapy monitoring in breast cancer.
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Affiliation(s)
- E Wehrse
- Division of Radiology, German Cancer Research Center, Heidelberg, Germany.
- Medical Faculty, Ruprecht-Karls-University Heidelberg, Heidelberg, Germany.
| | - S Sawall
- Medical Faculty, Ruprecht-Karls-University Heidelberg, Heidelberg, Germany
- Division of X-Ray Imaging and Computed Tomography, German Cancer Research Center, Heidelberg, Germany
| | - L Klein
- Division of X-Ray Imaging and Computed Tomography, German Cancer Research Center, Heidelberg, Germany
| | - P Glemser
- Division of Radiology, German Cancer Research Center, Heidelberg, Germany
| | - S Delorme
- Division of Radiology, German Cancer Research Center, Heidelberg, Germany
| | - H-P Schlemmer
- Division of Radiology, German Cancer Research Center, Heidelberg, Germany
| | - M Kachelrieß
- Medical Faculty, Ruprecht-Karls-University Heidelberg, Heidelberg, Germany
- Division of X-Ray Imaging and Computed Tomography, German Cancer Research Center, Heidelberg, Germany
| | - M Uhrig
- Division of Radiology, German Cancer Research Center, Heidelberg, Germany
| | - C H Ziener
- Division of Radiology, German Cancer Research Center, Heidelberg, Germany
| | - L T Rotkopf
- Division of Radiology, German Cancer Research Center, Heidelberg, Germany
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Sawall S, Klein L, Amato C, Wehrse E, Dorn S, Maier J, Heinze S, Schlemmer HP, Ziener C, Uhrig M, Kachelrieß M. Iodine contrast-to-noise ratio improvement at unit dose and contrast media volume reduction in whole-body photon-counting CT. Eur J Radiol 2020; 126:108909. [DOI: 10.1016/j.ejrad.2020.108909] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2019] [Revised: 02/09/2020] [Accepted: 02/14/2020] [Indexed: 10/25/2022]
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Uhrig M, Mueller J, Longerich T, Straub BK, Buschle LR, Schlemmer HP, Mueller S, Ziener CH. Susceptibility based multiparametric quantification of liver disease: Non-invasive evaluation of steatosis and iron overload. Magn Reson Imaging 2019; 63:114-122. [PMID: 31425813 DOI: 10.1016/j.mri.2019.08.016] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [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: 05/10/2019] [Revised: 07/11/2019] [Accepted: 08/15/2019] [Indexed: 02/07/2023]
Abstract
PURPOSE To evaluate if single-voxel MR spectroscopy (MRS) of iron and fat correlates with biopsy results of hepatic steatosis and iron overload, and to compare MR-measurements with room-temperature susceptometer (RTS), ultrasound, controlled attenuation parameter (CAP) and serum ferritin. MATERIAL AND METHODS In this prospective study, a set of 42 patients out of 47 screened patients with several chronic liver diseases underwent MRI-examination at 1.5 T including R2-measurements by single-voxel high-speed T2-corrected multiecho spectroscopy, additional liver biopsy, abdominal ultrasound, CAP, and RTS. Routine blood and serum parameters were determined, including ferritin. Atomic absorption spectroscopy (AAS) and histologically confirmed extent of hepatic steatosis from liver biopsy were used as reference standard. For correlation of R2, RTS, CAP, ferritin, and ultrasound with results of AAS and histologically determined fat fraction of liver biopsy specimen, Spearman's and Pearson's correlation as well as receiver operating characteristics curve (ROC) analysis with cut-off values determined by maximizing Youden index was used. RESULTS MRS iron assessment correlated best with AAS, with a Pearson correlation coefficient of 0.715 (p < 0.001), followed by RTS 0.520 (p < 0.001), and serum ferritin 0.213 (p = 0.088, not significant). MRS fat quantification correlated best with the histological confirmed extent of steatosis hepatis with a Spearman correlation coefficient of 0.836 (p < 0.001), followed by CAP 0.604 (p < 0.001) and sonographically diagnosed steatosis 0.358 (p = 0.013). CONCLUSION MRS by T2-corrected multiecho single-voxel spectroscopy correlated best with histological results of hepatic fat and iron content compared to RTS, CAP, abdominal ultrasound, and ferritin. Non-invasive methods to assess hepatic fat and iron are of clinical interest for follow-up examinations of patients with chronic liver diseases, where repeated biopsy is not indicated.
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Affiliation(s)
- Monika Uhrig
- German Cancer Research Center (DKFZ), Department of Radiology, D-69120 Heidelberg, Germany
| | - Johannes Mueller
- Dept. of Medicine, Salem Medical Center and Center for Alcohol Research, University Hospital Heidelberg, D-69120 Heidelberg, Germany
| | - Thomas Longerich
- Dept. of Pathology, University Hospital Heidelberg, D-69120 Heidelberg, Germany
| | - Beate Katharina Straub
- Dept. of Pathology, University Hospital Heidelberg, D-69120 Heidelberg, Germany; Dept. of Pathology, University Hospital Mainz, D-55131 Mainz, Germany
| | - Lukas R Buschle
- German Cancer Research Center (DKFZ), Department of Radiology, D-69120 Heidelberg, Germany; Faculty of Physics and Astronomy, University of Heidelberg, D-69120 Heidelberg, Germany
| | - Heinz-Peter Schlemmer
- German Cancer Research Center (DKFZ), Department of Radiology, D-69120 Heidelberg, Germany
| | - Sebastian Mueller
- Dept. of Medicine, Salem Medical Center and Center for Alcohol Research, University Hospital Heidelberg, D-69120 Heidelberg, Germany
| | - Christian H Ziener
- German Cancer Research Center (DKFZ), Department of Radiology, D-69120 Heidelberg, Germany.
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Dorn S, Chen S, Sawall S, Maier J, Knaup M, Uhrig M, Schlemmer HP, Maier A, Lell M, Kachelrieß M. Towards context-sensitive CT imaging - organ-specific image formation for single (SECT) and dual energy computed tomography (DECT). Med Phys 2018; 45:4541-4557. [DOI: 10.1002/mp.13127] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2018] [Revised: 07/30/2018] [Accepted: 08/03/2018] [Indexed: 12/31/2022] Open
Affiliation(s)
- Sabrina Dorn
- German Cancer Research Center (DKFZ); Im Neuenheimer Feld 280 69120 Heidelberg Germany
- Medical Faculty; Ruprecht-Karls-University Heidelberg; Im Neuenheimer Feld 672 69120 Heidelberg Germany
| | - Shuqing Chen
- Pattern Recognition Lab; Friedrich-Alexander-University Erlangen-Nürnberg; Martenstraße 3 91058 Erlangen Germany
| | - Stefan Sawall
- German Cancer Research Center (DKFZ); Im Neuenheimer Feld 280 69120 Heidelberg Germany
- Medical Faculty; Ruprecht-Karls-University Heidelberg; Im Neuenheimer Feld 672 69120 Heidelberg Germany
| | - Joscha Maier
- German Cancer Research Center (DKFZ); Im Neuenheimer Feld 280 69120 Heidelberg Germany
- Department of Physics and Astronomy; Ruprecht-Karls-University; Im Neuenheimer Feld 226 69120 Heidelberg Germany
| | - Michael Knaup
- German Cancer Research Center (DKFZ); Im Neuenheimer Feld 280 69120 Heidelberg Germany
| | - Monika Uhrig
- German Cancer Research Center (DKFZ); Im Neuenheimer Feld 280 69120 Heidelberg Germany
| | - Heinz-Peter Schlemmer
- German Cancer Research Center (DKFZ); Im Neuenheimer Feld 280 69120 Heidelberg Germany
| | - Andreas Maier
- Pattern Recognition Lab; Friedrich-Alexander-University Erlangen-Nürnberg; Martenstraße 3 91058 Erlangen Germany
| | - Michael Lell
- Department of Radiology and Nuclear Medicine; Klinikum Nürnberg, Paracelsus Medical University; Prof.-Ernst-Nathan-Strasse 1 90419 Nürnberg Germany
| | - Marc Kachelrieß
- German Cancer Research Center (DKFZ); Im Neuenheimer Feld 280 69120 Heidelberg Germany
- Medical Faculty; Ruprecht-Karls-University Heidelberg; Im Neuenheimer Feld 672 69120 Heidelberg Germany
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Uhrig M, Simons D, Schlemmer HP. Incidental pulmonary emboli in stage IV melanoma patients: Prevalence in CT staging examinations and improved detection with vessel reconstructions based on dual energy CT. PLoS One 2018; 13:e0199458. [PMID: 30001367 PMCID: PMC6042704 DOI: 10.1371/journal.pone.0199458] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Accepted: 06/07/2018] [Indexed: 11/19/2022] Open
Abstract
OBJECTIVES Malignancy is the strongest predictor for venous thromboembolism. Dual energy CT (DECT) can support assessment of pulmonary emboli (PE) by providing vessel reconstructions (DECT-VR) and highlighting thrombi. Purpose was to determine prevalence and risk factors of PE in staging examinations of stage IV-melanoma patients and to evaluate the potential of DECT-VR to improve PE diagnosis. MATERIAL AND METHODS This retrospective study was approved by IRB. Contrast-enhanced, conventional grey scale CT (cCT) and DECT-VR of 200 stage IV-melanoma patients were reviewed by three radiologists in consensus. Overall prevalence was determined. One-sided Wilcoxon-test was performed to compare the number of detected emboli between cCT and cCT with supplementary DECT-VR. Frequencies of risk factors were compared with χ2 test. RESULTS On cCT, 9 PE were detected (6 patients, correlating to 3% of the study population with 0.05 emboli per patient). With the supplementary DECT-VR, number of diagnosed emboli increased from 9 to 17 (p < 0.05) (in total 9 patients, correlating to 0.09 emboli per patient). Emboli on DECT-VR were mainly subsegmentally (7 of 8). There was no significant difference in the frequency of risk factors. CONCLUSIONS The prevalence of pulmonary emboli in our cohort of 200 stage IV melanoma patients was 5%. DECT-VR improved significantly diagnosis of PE, especially when located subsegmentally.
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Affiliation(s)
- Monika Uhrig
- German Cancer Research Center (DKFZ), Department of Radiology, Heidelberg, Germany
- * E-mail:
| | - David Simons
- German Cancer Research Center (DKFZ), Department of Radiology, Heidelberg, Germany
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Afshar-Oromieh A, Debus N, Uhrig M, Hope TA, Evans MJ, Holland-Letz T, Giesel FL, Kopka K, Hadaschik B, Kratochwil C, Haberkorn U. Impact of long-term androgen deprivation therapy on PSMA ligand PET/CT in patients with castration-sensitive prostate cancer. Eur J Nucl Med Mol Imaging 2018; 45:2045-2054. [PMID: 29980832 PMCID: PMC6182397 DOI: 10.1007/s00259-018-4079-z] [Citation(s) in RCA: 104] [Impact Index Per Article: 17.3] [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: 04/13/2018] [Accepted: 06/25/2018] [Indexed: 12/16/2022]
Abstract
Purpose Since the introduction of PSMA PET/CT with 68Ga-PSMA-11, this modality for imaging prostate cancer (PC) has spread worldwide. Preclinical studies have demonstrated that short-term androgen deprivation therapy (ADT) can significantly increase PSMA expression on PC cells. Additionally, retrospective clinical data in large patient cohorts suggest a positive association between ongoing ADT and a pathological PSMA PET/CT scan. The present evaluation was conducted to further analyse the influence of long-term ADT on PSMA PET/CT findings. Methods A retrospective analysis was performed of all 1,704 patients who underwent a 68Ga-PSMA-11 PET/CT scan at our institution from 2011 to 2017 to detect PC. Of 306 patients scanned at least twice, 10 had started and continued ADT with a continuous clinical response between the two PSMA PET/CT scans. These ten patients were included in the current analysis which compared the tracer uptake intensity and volume of PC lesions on PSMA PET/CT before and during ongoing ADT. Results Overall, 31 PC lesions were visible in all ten patients before initiation of ADT. However, during ongoing ADT (duration 42–369 days, median 230 days), only 14 lesions were visible in eight of the ten patients. The average tracer uptake values decreased in 71% and increased in 12.9% of the PC lesions. Of all lesions, 33.3% were still visible in six patients with a complete PSA response (≤0.1 ng/ml). Conclusion Continuous long-term ADT significantly reduces the visibility of castration-sensitive PC on PSMA PET/CT. If the objective is visualization of the maximum possible extent of disease, we recommend referring patients for PSMA PET/CT before starting ADT.
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Affiliation(s)
- Ali Afshar-Oromieh
- Department of Nuclear Medicine, Heidelberg University Hospital, Heidelberg, Germany. .,Department of Nuclear Medicine, Bern University Hospital, Freiburgstrasse 18, 3010, Bern, Switzerland.
| | - Nils Debus
- Department of Nuclear Medicine, Heidelberg University Hospital, Heidelberg, Germany
| | - Monika Uhrig
- Department of Radiology, German Cancer Research Center, Heidelberg, Germany
| | - Thomas A Hope
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, San Francisco, California, USA
| | - Michael J Evans
- Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, California, USA
| | - Tim Holland-Letz
- Department of Biostatistics, German Cancer Research Center, Heidelberg, Germany
| | - Frederik L Giesel
- Department of Nuclear Medicine, Heidelberg University Hospital, Heidelberg, Germany
| | - Klaus Kopka
- Division of Radiopharmaceutical Chemistry, German Cancer Research Center, Heidelberg, Germany.,German Cancer Consortium (DKTK), Heidelberg, Germany
| | - Boris Hadaschik
- Department of Urology, Essen University Hospital, University of Duisburg-Essen, Essen, Germany
| | - Clemens Kratochwil
- Department of Nuclear Medicine, Heidelberg University Hospital, Heidelberg, Germany
| | - Uwe Haberkorn
- Department of Nuclear Medicine, Heidelberg University Hospital, Heidelberg, Germany.,Clinical Cooperation Unit Nuclear Medicine, German Cancer Research Centre, Heidelberg, Germany
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Uhrig M, Simons D, Bonekamp D, Schlemmer HP. Improved detection of melanoma metastases by iodine maps from dual energy CT. Eur J Radiol 2017; 90:27-33. [PMID: 28583644 DOI: 10.1016/j.ejrad.2017.02.024] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [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: 09/09/2016] [Revised: 12/29/2016] [Accepted: 02/15/2017] [Indexed: 01/01/2023]
Abstract
OBJECTIVE Metastatic disease in melanoma has an unpredictable nature with deposits in rare locations such as musculature. Dual energy CT (DECT) provides high contrast-visualization of enhancement by using spectral properties of iodine. Purpose of this study was to evaluate whether iodine maps from DECT improve lesion detection in staging examinations of melanoma patients. METHODS This retrospective study was approved by IRB and written informed consent was obtained from all patients. 75 contrast-enhanced DECT scans (thorax and abdomen) from 75 melanoma patients (n=69 stage IV; n=6 stage III) were analysed. For each patient, conventional CT and iodine maps were reviewed independently by two radiologists. The number of lesions detected by reviewing the iodine maps following conventional CT was recorded. Unweighted Cohens Kappa coefficient (κ) was used for concordance analysis, Wilcoxon test for comparing lesion detection rates. RESULTS In 26 patients, at least one reader found additional lesions on iodine maps (inter-reader agreement 89%, κ=0.74 (0.742-0.747)). Compared to grey-scale images, mean detection rate for metastases improved from 86% (range 82-90) to 94% (90-99%) (p≤0.01), for muscle metastases from 8% (8-8%) to 99% (98-100%) (p≤0.06). Findings included 2 pulmonary emboli. CONCLUSION Iodine maps from DECT improve detection of metastases, especially muscle metastases, and relevant findings in staging examinations of melanoma patients.
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Affiliation(s)
- Monika Uhrig
- German Cancer Research Center (DKFZ), Department of Radiology, Im Neuenheimer Feld 280, D-69120, Heidelberg, Germany.
| | - David Simons
- German Cancer Research Center (DKFZ), Department of Radiology, Im Neuenheimer Feld 280, D-69120, Heidelberg, Germany
| | - David Bonekamp
- German Cancer Research Center (DKFZ), Department of Radiology, Im Neuenheimer Feld 280, D-69120, Heidelberg, Germany
| | - Heinz-Peter Schlemmer
- German Cancer Research Center (DKFZ), Department of Radiology, Im Neuenheimer Feld 280, D-69120, Heidelberg, Germany
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Uhrig M, Simons D, Kachelrieß M, Pisana F, Kuchenbecker S, Schlemmer HP. Advanced abdominal imaging with dual energy CT is feasible without increasing radiation dose. Cancer Imaging 2016; 16:15. [PMID: 27329159 PMCID: PMC4915171 DOI: 10.1186/s40644-016-0073-5] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [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: 05/20/2016] [Accepted: 06/14/2016] [Indexed: 01/28/2023] Open
Abstract
Background Dual energy CT (DECT) has proven its potential in oncological imaging. Considering the repeated follow-up examinations, radiation dose should not exceed conventional single energy CT (SECT). Comparison studies on the same scanner with a large number of patients, considering patient geometries and image quality, and exploiting full potential of SECT dose reduction are rare. Purpose of this retrospective study was to compare dose of dual source DECT versus dose-optimized SECT abdominal imaging in clinical routine. Methods One hundred patients (62y (±14)) had either contrast-enhanced SECT including automatic voltage control (44) or DECT (56). CT dose index (CTDIvol), size-specific dose-estimate (SSDE) and dose-length product (DLP) were reported. Image noise (SD) was recorded as mean of three ROIs placed in subcutaneous fat and normalized to dose by \documentclass[12pt]{minimal}
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\begin{document}$$ SDn=SD\times \sqrt{CDTIvol} $$\end{document}SDn=SD×CDTIvol. For dose-normalized contrast-to-noise ratio (CNRD), mean attenuation of psoas muscle (CTmuscle) and subcutaneous fat (CTfat) were compared by CNRD = (CTmuscle − CTfat)/SDn. Statistical significance was tested with two-sided t-test (α = 0.05). Results There was no significant difference (p < 0.05) between DECT and SECT: Mean CTDIvol was 14.2 mGy (±3.9) (DECT) and 14.3 mGy (±4.5) (SECT). Mean DLP was 680 mGy*cm (±220) (DECT) and 665 mGy*cm (±231) (SECT). Mean SSDE was 15.7 mGy (±1.9) (DECT) and 16.1 mGy (±2.5) (SECT). Mean SDn was 42.2 (±13.9) HU \documentclass[12pt]{minimal}
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\begin{document}$$ *\sqrt{\mathrm{mGy}} $$\end{document}*mGy (DECT) and 47.8 (±14.9) HU \documentclass[12pt]{minimal}
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\begin{document}$$ *\sqrt{\mathrm{mGy}} $$\end{document}*mGy (SECT). Mean CNRD was 3.9 (±1.3) \documentclass[12pt]{minimal}
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\begin{document}$$ {\mathrm{mGy}}^{-\frac{1}{2}} $$\end{document}mGy−12. (DECT) and 4.0 (±1.3) \documentclass[12pt]{minimal}
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\begin{document}$$ {\mathrm{mGy}}^{-\frac{1}{2}} $$\end{document}mGy−12 (SECT). Conclusion Abdominal DECT is feasible without increasing radiation dose or deteriorating image quality, even compared to dose-optimized SECT including automatic voltage control. Thus DECT can contribute to sophisticated oncological imaging without dose penalty.
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Affiliation(s)
- Monika Uhrig
- Department of Radiology, German Cancer Research Center (DKFZ) Heidelberg, Im Neuenheimer Feld 280, D-69120, Heidelberg, Germany.
| | - David Simons
- Department of Radiology, German Cancer Research Center (DKFZ) Heidelberg, Im Neuenheimer Feld 280, D-69120, Heidelberg, Germany
| | - Marc Kachelrieß
- Department of Medical Physics in Oncology, Division of X-Ray Imaging and Computed Tomography, German Cancer Research Center (DKFZ) Heidelberg, Im Neuenheimer Feld 280, D-69120, Heidelberg, Germany
| | - Francesco Pisana
- Department of Medical Physics in Oncology, Division of X-Ray Imaging and Computed Tomography, German Cancer Research Center (DKFZ) Heidelberg, Im Neuenheimer Feld 280, D-69120, Heidelberg, Germany
| | - Stefan Kuchenbecker
- Department of Medical Physics in Oncology, Division of X-Ray Imaging and Computed Tomography, German Cancer Research Center (DKFZ) Heidelberg, Im Neuenheimer Feld 280, D-69120, Heidelberg, Germany
| | - Heinz-Peter Schlemmer
- Department of Radiology, German Cancer Research Center (DKFZ) Heidelberg, Im Neuenheimer Feld 280, D-69120, Heidelberg, Germany
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Uhrig M, Simons D, Ganten MK, Hassel JC, Schlemmer HP. Histogram analysis of iodine maps from dual energy computed tomography for monitoring targeted therapy of melanoma patients. Future Oncol 2015; 11:591-606. [PMID: 25686115 DOI: 10.2217/fon.14.265] [Citation(s) in RCA: 15] [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] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
AIM Iodine quantification with dual energy computed tomography (DECT) enables quantitative assessment of contrast medium uptake. Our purpose was to investigate patterns of enhancement under BRAF inhibitor therapy by performing histogram analyses (HAs) of iodine maps. MATERIALS & METHODS A total of 11 stage IV melanoma patients (32 metastases) underwent DECT at baseline and at least one follow up. Iodine uptake and HAs including maximum HU value (MAX), mean HU value (MEAN) and standard deviation (STD) was calculated. RESULTS For BRAF-responders MEAN, MAX and STD decreased significantly (p < 0.05). Nonresponder showed increasing MAX and STD for six out of seven lesions, while MEAN and Iodine uptake decreased (four) and increased (three). CONCLUSION HA based on DECT enables a quantitative and functional criterion and contributes to accurate response assessment for promising targeted therapies.
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Affiliation(s)
- Monika Uhrig
- Department of Radiology, German Cancer Research Center (DKFZ) Heidelberg, Im Neuenheimer Feld 280; D-69120 Heidelberg, Germany
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Simons D, Reicht I, Uhrig M, Fangerau M, Yen K, Schlemmer H. Radiology infrastructure for non-radiologists: building a mobile and cost-effective DICOM viewing based forensic-radiologic network. ROFO-FORTSCHR RONTG 2015. [DOI: 10.1055/s-0035-1550791] [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: 10/23/2022]
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Uhrig M, Simons D, Ganten M, Hassel J, Schlemmer HP. Dual-energy CT for therapy monitoring: histogram analyses of iodine maps reveal typical pattern of enhancement. Cancer Imaging 2014. [PMCID: PMC4241994 DOI: 10.1186/1470-7330-14-s1-p17] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Simons D, Uhrig M, Sassenberg A, Breithaupt M, Berger M, Yen K, Schlemmer HP. Experimentelle 7 Tesla MRT basierte innovative Blutungsdetektion in der Rechtsmedizin. ROFO-FORTSCHR RONTG 2014. [DOI: 10.1055/s-0034-1373567] [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: 10/25/2022]
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Uhrig M, Sedlmair M, Schlemmer HP, Hassel JC, Ganten M. Monitoring targeted therapy using dual-energy CT: semi-automatic RECIST plus supplementary functional information by quantifying iodine uptake of melanoma metastases. Cancer Imaging 2013; 13:306-13. [PMID: 23876444 PMCID: PMC3719051 DOI: 10.1102/1470-7330.2013.0031] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [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] [Subscribe] [Scholar Register] [Accepted: 05/15/2013] [Indexed: 01/20/2023] Open
Abstract
AIM Supplementary functional information can contribute to assess response in targeted therapies. The aim of this study was to evaluate semi-automatic RECIST plus iodine uptake (IU) determination in melanoma metastases under BRAF inhibitor (vemurafenib) therapy using dual-energy computed tomography (DECT). METHODS Nine patients with stage IV melanoma treated with a BRAF inhibitor were included. Contrast-enhanced DECT was performed before and twice after treatment onset. Changes in tumor size were assessed according to RECIST. Quantification of IU (absolute value for total IU (mg) and volume-normalized IU (mg/ml)) was based on semi-automatic tumor volume segmentation. The decrease compared with baseline was calculated. RESULTS The mean change of RECIST diameter sum per patient was -47% at the first follow-up (FU), -56% at the second FU (P < 0.01). The mean normalized IU per patient was -21% at the first FU (P < 0.2) and -45% at the second FU (P < 0.01). Total IU per patient, combining both normalized IU and volume, showed the most pronounced decrease: -89% at the first FU and -90% at the second FU (P < 0.01). CONCLUSION Semi-automatic RECIST plus IU quantification in DECT enables objective, easy and fast parameterization of tumor size and contrast medium uptake, thus providing 2 complementary pieces of information for response monitoring applicable in daily routine.
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Affiliation(s)
- M Uhrig
- Department of Radiology, German Cancer Research Center, Im Neuenheimer Feld 280, Heidelberg, D-69120, Germany.
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Uhrig M, Sedlmair M, Schlemmer HP, Hassel JC, Ganten MK. Verlaufskontrollen zielgerichteter Therapien mittels Dual Energy CT: semi-automatische Kontrastmittelquantifizierung mit integrierter RECIST-Beurteilung bei Melanommetastasen. ROFO-FORTSCHR RONTG 2013. [DOI: 10.1055/s-0033-1346420] [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: 10/26/2022]
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Uhrig M, Thieke C, Alonso F, Küfer K, Monz M, Scherrer A, Oelfke U. SU-FF-T-112: First Evaluation of a New Multicriteria Optimization Tool-Investigation of Pareto-Surfaces for IMRT Prostate Plans. Med Phys 2005. [DOI: 10.1118/1.1997783] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [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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Craft D, Bortfeld T, Halabi T, Martin B, Uhrig M. SU-FF-T-116: Multicriteria IMRT Planning with Equivalent Uniform Dose (EUD) Objectives: Tumor Dose Homogeneity vs. Critical Structure Sparing. Med Phys 2005. [DOI: 10.1118/1.1997787] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [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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Andersen N, Bartschat K, Broad JT, Hanne GF, Uhrig M. Spin-dependent orientation propensities revealed in polarized-electron-polarized-photon coincidence studies. Phys Rev Lett 1996; 76:208-211. [PMID: 10061043 DOI: 10.1103/physrevlett.76.208] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Efner H, Kirk R, Noftle R, Uhrig M. Preparation of some new pentafluorosulfur fluoroethanes; the vibrational spectrum of 1-hydro-1-pentafluorosulfur-F-ethane and its deuterium isotopomer. Polyhedron 1982. [DOI: 10.1016/s0277-5387(00)81056-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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