23 results on '"Mareen Sarah Kraus"'
Search Results
2. Radiation Dose Reduction in CT Torsion Measurement of the Lower Limb: Introduction of a New Ultra-Low Dose Protocol
- Author
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Gabriel Keller, Simon Götz, Mareen Sarah Kraus, Leonard Grünwald, Fabian Springer, and Saif Afat
- Subjects
radiation exposure ,radiation dosage ,rotation ,torsion ,lower limb ,lower extremity ,Medicine (General) ,R5-920 - Abstract
This study analyzed the radiation exposure of a new ultra-low dose (ULD) protocol compared to a high-quality (HQ) protocol for CT-torsion measurement of the lower limb. The analyzed patients (n = 60) were examined in the period March to October 2019. In total, 30 consecutive patients were examined with the HQ and 30 consecutive patients with the new ULD protocol comprising automatic tube voltage selection, automatic exposure control, and iterative image reconstruction algorithms. Radiation dose parameters as well as the contrast-to-noise ratio (CNR) and diagnostic confidence (DC; rated by two radiologists) were analyzed and potential predictor variables, such as body mass index and body volume, were assessed. The new ULD protocol resulted in significantly lower radiation dose parameters, with a reduction of the median total dose equivalent to 0.17 mSv in the ULD protocol compared to 4.37 mSv in the HQ protocol (p < 0.001). Both groups showed no significant differences in regard to other parameters (p = 0.344–0.923). CNR was 12.2% lower using the new ULD protocol (p = 0.033). DC was rated best by both readers in every HQ CT and in every ULD CT. The new ULD protocol for CT-torsion measurement of the lower limb resulted in a 96% decrease of radiation exposure down to the level of a single pelvic radiograph while maintaining good image quality.
- Published
- 2021
- Full Text
- View/download PDF
3. Ultra-low dose CT for scaphoid fracture detection—a simulational approach to quantify the capability of radiation exposure reduction without diagnostic limitation
- Author
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Gabriel, Keller, Florian, Hagen, Leoni, Neubauer, Katarzyna, Rachunek, Fabian, Springer, and Mareen Sarah, Kraus
- Subjects
Radiology, Nuclear Medicine and imaging - Abstract
Modern CT might deliver higher image quality than necessary for fracture imaging, which would mean non-essential effective radiation exposure for patients. We simulated ultra-low dose (ULD)-CT at different dose levels and analyzed their diagnostic performance for scaphoid fracture detection.30 consecutive high quality CT with clinically suspected scaphoid fractures were assessed. ULD-simulations were made at 20%, 10% and 5% of original dose. Three readers at different levels of experience (expert, moderate, inexperienced) expressed their diagnostic confidence (DC; 5-point-Likert-scale) and analyzed the presence and classification of scaphoid fractures within Krimmer's and Herbert's classifications. Effective radiation exposure of the original data sets and ULD-CT were calculated.At 20% and 10% dose the more experienced readers reached perfect sensitivity (100%) and specificity (100%), showing perfect agreement regarding fracture classification (1.00). Diagnostic performance decreased at 5% dose (92.86% sensitivity, 100% specificity; expert reader). The inexperienced reader showed reduced sensitivity and specificity at all dose levels. At 10% dose minimal DC of all readers was 3/5 and mean calculated effective radiation exposure was 1.11 [±0.36] µSv.The results suggest that ULD-CT at 10% dose compared to high quality CT might offer sufficient image quality to precisely detect and classify scaphoid fractures, if moderate experience of the radiologist is granted.
- Published
- 2022
4. Effectiveness of Chest CT in Children: CT Findings in Relation to the Clinical Question
- Author
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Michael Esser, Jürgen F. Schaefer, Ilias Tsiflikas, Sabine Hess, Mareen Sarah Kraus, and Sergios Gatidis
- Subjects
Thorax ,medicine.medical_specialty ,business.industry ,Chest ct ,Retrospective cohort study ,Pneumonia ,University hospital ,medicine.disease ,Pediatric Radiology ,Clinical question ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Ct findings ,Radiology ,Child ,Tomography, X-Ray Computed ,business ,Retrospective Studies - Abstract
To estimate the effectiveness and efficiency of chest CT in children based on the suspected diagnosis in relation to the number of positive, negative, and inconclusive CT results.In this monocentric retrospective study at a university hospital with a division of pediatric radiology, 2019 chest CT examinations (973 patients; median age: 10.5 years; range: 2 days to 17.9 years) were analyzed with regards to clinical data, including the referring department, primary questions or suspected diagnosis, and CT findings. It was identified if the clinical question was answered, whether the suspected diagnosis was confirmed or ruled out, and if additional findings (clinically significant or minor) were detected.The largest clinical subgroup was the hematooncological subgroup (n = 987), with frequent questions for inflammation/pneumonia (66 % in this subgroup). Overall, CT provided conclusive results in 97.6 % of all scans. In 1380 scans (70 %), the suspected diagnosis was confirmed. In 406/2019 cases (20 %), the CT scan was negative also in terms of an additional finding. In 8 of 9 clinical categories, the proportion of positive results was over 50 %. There were predominantly negative results (110/179; 61 %) in pre-stem cell transplant evaluation. In the subgroup of trauma management, 81/144 exams (57 %) showed positive results, including combined injuries (n = 23). 222/396 (56 %) of all additional findings were estimated to be clinically significant.In a specialized center, the effectiveness of pediatric chest CT was excellent when counting the conclusive results. However, to improve efficiency, the clinical evaluation before imaging appears crucial to prevent unnecessary CT examinations.· Pediatric chest CT in specialized centers has a high diagnostic value.. · CT identifies relevant changes besides the working hypothesis in clinically complex situations.. · Pre-CT clinical evaluation is crucial, especially in the context of suspected pneumonia..· Esser M, Tsiflikas I, Kraus MS et al. Effectiveness of Chest CT in Children: CT Findings in Relation to the Clinical Question. Fortschr Röntgenstr 2022; 194: 281 - 290.ZIEL: Abschätzung der klinischen Wertigkeit der Thorax-CT bei Kindern auf Grundlage der Verdachtsdiagnose und positiven, negativen und inkonklusiven CT-Befunde.In dieser retrospektiven monozentrischen Studie an einer Universitätsklinik mit Abteilung für Kinderradiologie wurden 2019 Thorax-CTs (973 Patienten; Altersmedian 10,5 Jahre; Spannweite: 2 Tage bis 17,9 Jahre) hinsichtlich klinischer Daten analysiert, einschließlich Zuweiserinformationen, primärer Fragestellungen oder Verdachtsdiagnosen und CT-Befunde. Es wurde festgehalten, ob die klinische Fragestellung beantwortet wurde, ob die Verdachtsdiagnose bestätigt oder ausgeschlossen wurde und ob Nebenbefunde (klinisch signifikant oder irrelevant) festgestellt wurden.Die größte klinische Untergruppe bestand aus hämatoonkologischen Fällen (n = 987) mit häufiger Fragestellung eines pulmonalen Infektfokus (66 % in dieser Gruppe). Insgesamt lieferte die CT in 97,6 % aller CTs konklusive Resultate. In 1380 CTs (70 %) wurde die Verdachtsdiagnose bestätigt. In 406/2019 Fällen (20 %) wurde weder ein primärer Befund noch ein Nebenbefund festgestellt. In 8 von 9 klinischen Kategorien war der Anteil der positiven Ergebnisse über 50 %. Vorwiegend negative Ergebnisse (110/179; 61 %) traten bei Patienten vor Stammzelltransplantation auf. In der Gruppe der Traumapatienten lieferten 81/144 der Untersuchungen (57 %) positive Ergebnisse, einschließlich mehrerer kombinierter Verletzungen (n = 23). 222/396 aller Nebenbefunde (56 %) wurden als klinisch relevant eingestuft.Die pädiatrische Thorax-CT in spezialisierten Zentren hat eine hohe diagnostische Aussagekraft im Hinblick auf konklusive Untersuchungsergebnisse. Zur Verbesserung der Effizienz der Methode und Prävention unnötiger CT-Untersuchungen ist die klinische Beurteilung prä-CT entscheidend.· Die pädiatrische Thorax-CT in spezialisierten Zentren hat eine hohe diagnostische Aussagekraft.. · Die CT kann in klinisch komplexen Situationen relevante Veränderungen neben der Arbeitshypothese erkennen.. · Die klinische Beurteilung prä-CT ist unentbehrlich, insbesondere bei Verdacht auf eine Pneumonie..
- Published
- 2021
5. State-of-the-art magnetic resonance imaging sequences for pediatric body imaging
- Author
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Mareen Sarah Kraus, Ailish C. Coblentz, Vibhas S. Deshpande, Johannes M. Peeters, Pedro M. Itriago-Leon, and Govind B. Chavhan
- Subjects
Pediatrics, Perinatology and Child Health ,Radiology, Nuclear Medicine and imaging - Published
- 2022
6. Ossäre Normvarianten in der radiologischen Diagnostik des Handgelenks
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Fabian Springer, Mareen Sarah Kraus, and Cecilia Zhang
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03 medical and health sciences ,0302 clinical medicine ,business.industry ,030220 oncology & carcinogenesis ,Carpal coalition ,Medicine ,Radiology, Nuclear Medicine and imaging ,Madelung deformity ,Nuclear medicine ,business ,030218 nuclear medicine & medical imaging - Abstract
Das Handgelenk stellt mit zahlreichen an ihm beteiligten Knochen eines der komplexesten Gelenke des Korpers dar. Es besitzt eine hohe Flexibilitat bei ausgezeichneter Stabilitat. Die Variationsbreite der knochernen Strukturen, welche zugleich Ursache oder Differenzialdiagnose von pathologischen Veranderungen sein kann, stellt den befundenden Radiologen vor differenzialdiagnostische Schwierigkeiten. Nur die Kenntnis der wichtigsten ossaren Normvarianten erlaubt eine fundierte Befundung des Handgelenks. Als radiologisches Standardverfahren zur Untersuchung der knochernen Strukturen des Handgelenks ist in erster Linie die konventionelle Rontgendiagnostik zu nennen, gefolgt von der Computertomographie (CT) und im Zuge dezidierter Fragestellungen ggf. auch der Magnetresonanztomographie (MRT). Andere Verfahren, wie z. B. die Sonographie oder Szintigraphie, haben in der Routinediagnostik der ossaren Strukturen keinen Stellenwert. Neben der Reduktion der effektiven Strahlendosis haben sich seit der Einfuhrung der Mehrzeilenspiral-CT keine wesentlichen Innovationen in der klinischen Routinediagnostik zur Beurteilung der knochernen Strukturen des Handgelenks durchgesetzt. Als initiales diagnostisches Verfahren erlaubt meist das konventionelle Rontgen bereits eine sichere Diagnose im Bereich der knochernen Strukturen; bestehen jedoch bildmorphologische Unklarheiten oder eine Diskrepanz zwischen klinischem Befund und konventionell radiologischer Bildgebung, sollte zeitnah eine weitere Abklarung mittels CT erfolgen. Nur bei speziellen Fragestellungen oder zur Reduktion der Strahlenexposition bei Kindern ist eine MRT in der klinischen Routine indiziert.
- Published
- 2021
7. Differing Pulmonary Structural Abnormalities Detected on Pulmonary MR Imaging in Cystic Fibrosis Patients with Varying Pancreatic Function
- Author
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Michael Esser, Ute Graepler-Mainka, Andreas Hector, M Teufel, Jürgen F. Schaefer, Sabrina Fleischer, Ilias Tsiflikas, Lena S. Kiefer, and Mareen Sarah Kraus
- Subjects
Male ,medicine.medical_specialty ,Adolescent ,Cystic Fibrosis ,Genotype ,Sacculation ,Atelectasis ,Air trapping ,Gastroenterology ,Cystic fibrosis ,030218 nuclear medicine & medical imaging ,Pulmonary function testing ,03 medical and health sciences ,0302 clinical medicine ,Internal medicine ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Child ,Lung ,Retrospective Studies ,Bronchiectasis ,business.industry ,medicine.disease ,Magnetic Resonance Imaging ,Respiratory Function Tests ,Pancreatic Function Tests ,Phenotype ,medicine.anatomical_structure ,030228 respiratory system ,Female ,medicine.symptom ,Pancreas ,business - Abstract
In cystic fibrosis (CF) the phenotypic expression of complaints varies widely. Genotypes with sufficient pancreatic function (PS) exhibit milder lung disease compared to CF patients with insufficient pancreatic function (PI). The purpose of this study was to evaluate structural lung disease (SLD) in CF patients with differing pancreatic status but similar results on pulmonary function testing using a pulmonary magnetic resonance imaging score (MR-CF score). In this retrospective study, 20 patients in our single-center CF database were included: 10 with PS (mean age 12.5 years; six male; BMI 17.4 kg/m Patients with CF-PS had overall statistically significant lower MR-CF scores (p = 0.024), and therefore milder SLD, compared to CF-PI. The differences were most significant for bronchiectasis (p = 0.0042) and air trapping (p = 0.0304). SLD was more severe in the upper lobes in all patients. However, differences between CF-PS and CF-PI patients were present in both the upper and lower lung areas (p = 0.0247 and p = 0.0196, respectively). Our results demonstrated that CF patients with impaired pancreatic function show more severe lung pathology detected by MRI, especially bronchiectasis and air trapping. · Pulmonary MRI offers morphological and functional details without using ionizing radiation. · CF patients with pancreatic insufficiency show more severe pulmonary structural impairment. · Bronchiectasis and air trapping are the most common structural lung changes with predominance in the upper lung lobes..· Kraus MS, Teufel M, Esser M et al. Differing Pulmonary Structural Abnormalities Detected on Pulmonary MR Imaging in Cystic Fibrosis Patients with Varying Pancreatic Function. Fortschr Röntgenstr 2020; 192: 567 - 575.ZIEL: Die Multisystemerkrankung zystische Fibrose (CF) zeigt phänotypisch eine große Symptomvarianz, wobei Genotypen mit suffizienter Pankreasfunktion (PS) eine mildere Lungenbeeinträchtigung aufzuweisen scheinen im Vergleich zu pankreasinsuffizienten (PI) CF-Patienten. Ziel dieser Studie war die Evaluation von strukturellen Lungengerüstveränderungen (SLD) bei CF-Patienten mit unterschiedlicher Pankreasfunktion mittels pulmonalem MRT-Score (MR-CF-Score). 20 CF-Patienten wurden in diese retrospektive monozentrische Studie eingeschlossen: 10 PS-CF-Patienten (mittleres Alter 12,5 Jahre; 6 männlich; BMI 17,4 kg/m CF-PS-Patienten zeigten einen signifikant niedrigeren MR-CF-Gesamtscore (p = 0,024) und damit mildere Lungengerüstveränderungen. Die größten kategorischen Unterschiede waren bezüglich Bronchiektasien (p = 0,0042) und Überblähung (p = 0,0304) zu beobachten. SLD waren insbesondere in den Lungenoberfeldern am deutlichsten, jedoch zeigten sich signifikante Unterschiede in Bezug auf die Pankreasfunktion in sowohl den Lungenober- als auch -unterfeldern (p = 0,0247 und p = 0,0196). Unsere Ergebnisse zeigen signifikante Unterschiede bezüglich SLD und Pankreasstatus bei CF-Patienten mit identischen Lungenfunktionswerten. Pankreasinsuffiziente Patienten zeigten hierbei deutlich schwerere Lungengerüstveränderungen im MRT, insbesondere Bronchiektasien und Überblähung. · Pulmonales MRT ermöglicht eine morphologische und funktionelle Diagnostik ohne Einsatz ionisierender Strahlung.. · CF-Patienten mit insuffizienter Pankreasfunktion zeigen ausgeprägtere strukturelle Lungengerüstveränderungen im Vergleich zu pankreassuffizienten Patienten bei gleicher Lungenfunktion.. · Bronchiektasien und Überblähung sind die häufigsten strukturellen Lungengerüstveränderungen mit Betonung der Lungenoberfelder..
- Published
- 2020
8. New severity assessment in cystic fibrosis: signal intensity and lung volume compared to LCI and FEV1: preliminary results
- Author
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Winfried Baden, Mareen Sarah Kraus, Sabrina Fleischer, Andreas Hector, Sergios Gatidis, Juergen F. Schaefer, Ilias Tsiflikas, and Dominik Hartl
- Subjects
medicine.medical_specialty ,Lung ,medicine.diagnostic_test ,business.industry ,Magnetic resonance imaging ,General Medicine ,Lung Clearance Index ,medicine.disease ,Cystic fibrosis ,030218 nuclear medicine & medical imaging ,Pulmonary function testing ,03 medical and health sciences ,0302 clinical medicine ,medicine.anatomical_structure ,030220 oncology & carcinogenesis ,medicine ,Radiology, Nuclear Medicine and imaging ,Lung volumes ,Expiration ,Radiology ,Respiratory system ,Nuclear medicine ,business - Abstract
Magnetic resonance imaging (MRI) aids diagnosis in cystic fibrosis (CF) but its use in quantitative severity assessment is under research. This study aims to assess changes in signal intensity (SI) and lung volumes (Vol) during functional MRI and their use as a severity assessment tool in CF patients. The CF intra-hospital standard chest 1.5 T MRI protocol comprises of very short echo-time sequences in submaximal in- and expiration for functional information. Quantitative measurements (Vol/SI at in- and expiration, relative differences (Vol_delta/SI_delta), and cumulative histograms for normalized SI values across the expiratory lung volume) were assessed for correlation to pulmonary function: lung clearance index (LCI) and forced expiratory volume in 1 s (FEV1). In 49 patients (26 male, mean age 17 ± 7 years) significant correlation of Vol_delta and SI_delta (R = 0.86; p 10). The expiratory volume at a relative SI of 100% correlated significantly to LCI (R = 0.676 and 0.627; p 4% was associated with pathological pulmonary function values. Functional pulmonary MRI provides a radiation-free severity assessment tool and can contribute to early detection of lung impairment in CF. Lung volume with SI below 100% of the inspiratory volume represents overinflated tissue; an amount of 4% of the expiratory lung volume was a relevant turning point. • Signal intensity and lung volumes are used as potential metric parameters for lung impairment. • Quantification of trapped air impacts on therapy management. • Functional pulmonary MRI can contribute to early detection of lung impairment.
- Published
- 2019
9. Advanced Virtual Monoenergetic Imaging: Improvement of Visualization and Differentiation of Intramuscular Lesions in Portal-Venous-phase Contrast-enhanced Dual-energy CT
- Author
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Lena S. Kiefer, Mareen Sarah Kraus, Nadja Selo, Michael Esser, Fabian Bamberg, Julian L. Wichmann, Jakob Weiss, Ahmed E. Othman, and Omar M. Albtoush
- Subjects
Male ,Image quality ,media_common.quotation_subject ,Contrast Media ,Malignancy ,Portal venous phase ,030218 nuclear medicine & medical imaging ,Radiography, Dual-Energy Scanned Projection ,Lesion ,03 medical and health sciences ,0302 clinical medicine ,Humans ,Medicine ,Contrast (vision) ,Radiology, Nuclear Medicine and imaging ,Muscle, Skeletal ,Retrospective Studies ,media_common ,Muscle Neoplasms ,Receiver operating characteristic ,Portal Vein ,business.industry ,Virtual Reality ,Virtual monoenergetic imaging ,Middle Aged ,medicine.disease ,ROC Curve ,030220 oncology & carcinogenesis ,Female ,Dual energy ct ,medicine.symptom ,Tomography, X-Ray Computed ,business ,Nuclear medicine ,Algorithms - Abstract
Purpose To evaluate the effect of advanced monoenergetic imaging (MEI+) postprocessing algorithm on the visualization of various intramuscular lesions on portal-venous-phase contrast-enhanced dual-energy computed tomography (DECT). Material and Methods Thirty-nine patients (64.3 ± 11.1 years; 26 males) with various intramuscular lesions ranging from malignancy, bleeding, inflammation, edematous changes, and benign neoplasms were included and underwent DECT (100/Sn150kV). Postprocessing with MEI+ technique was used to reconstruct images at four different keV levels (40, 60, 80, 100) and compared to the standard portal-venous-phase CT (CTpv) images. Image quality was assessed qualitatively (conspicuity, delineation, sharpness, noise, and confidence) by two independent readers using 5-point Likert scales, 5 = excellent; as well as quantitatively by calculating signal-to-noise ratios (SNR), contrast-to-noise ratios (CNR), and area under the receiver operating characteristic (ROC) curve (AUC) for lesion characterization. Results Highest lesion enhancement and diagnostic confidence were observed in MEI+ 40 keV, with significant differences to CTpv (p Conclusion MEI+ at low keV levels can significantly improve lesion detection of benign versus malignant intramuscular entities in patients undergoing portal-venous-phase DECT scans due to increased CNR.
- Published
- 2019
10. Radiation Dose Reduction in CT Torsion Measurement of the Lower Limb: Introduction of a New Ultra-Low Dose Protocol
- Author
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Afat, Gabriel Keller, Simon Götz, Mareen Sarah Kraus, Leonard Grünwald, Fabian Springer, and Saif
- Subjects
radiation exposure ,radiation dosage ,rotation ,torsion ,lower limb ,lower extremity ,ultra-low dose ,ULD - Abstract
This study analyzed the radiation exposure of a new ultra-low dose (ULD) protocol compared to a high-quality (HQ) protocol for CT-torsion measurement of the lower limb. The analyzed patients (n = 60) were examined in the period March to October 2019. In total, 30 consecutive patients were examined with the HQ and 30 consecutive patients with the new ULD protocol comprising automatic tube voltage selection, automatic exposure control, and iterative image reconstruction algorithms. Radiation dose parameters as well as the contrast-to-noise ratio (CNR) and diagnostic confidence (DC; rated by two radiologists) were analyzed and potential predictor variables, such as body mass index and body volume, were assessed. The new ULD protocol resulted in significantly lower radiation dose parameters, with a reduction of the median total dose equivalent to 0.17 mSv in the ULD protocol compared to 4.37 mSv in the HQ protocol (p < 0.001). Both groups showed no significant differences in regard to other parameters (p = 0.344–0.923). CNR was 12.2% lower using the new ULD protocol (p = 0.033). DC was rated best by both readers in every HQ CT and in every ULD CT. The new ULD protocol for CT-torsion measurement of the lower limb resulted in a 96% decrease of radiation exposure down to the level of a single pelvic radiograph while maintaining good image quality.
- Published
- 2021
- Full Text
- View/download PDF
11. Author response for 'Distribution Patterns of Intra‐ and Extramyocellular Fat by Magnetic Resonance Imaging in Subjects with Diabetes, Prediabetes and Normoglycemic Controls'
- Author
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Thierno D. Diallo, Susanne Rospleszcz, Jana Fabian, Konstantin Nikolaou, Christa Meisinger, Lena S. Kiefer, Jürgen Machann, Frank W. Roemer, Christopher L. Schlett, Annette Peters, Wolfgang Rathmann, Fabian Bamberg, Roberto Lorbeer, Mareen Sarah Kraus, Margit Heier, and Corinna Storz
- Subjects
medicine.medical_specialty ,medicine.diagnostic_test ,business.industry ,Diabetes mellitus ,Internal medicine ,medicine ,Cardiology ,Distribution (pharmacology) ,Magnetic resonance imaging ,Prediabetes ,medicine.disease ,business - Published
- 2021
12. FDG PET/MRT zur Detektion von inflammatorischen pulmonalen Veränderungen bei Kindern mit zystischer Fibrose
- Author
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Mareen Sarah Kraus, Jürgen F. Schäfer, P Utz, Ilias Tsiflikas, Sergios Gatidis, Helmut Dittmann, Michael Esser, Ute Graepler-Mainka, and R Schwarz
- Published
- 2021
13. MRT der Lunge: Langjährige Überwachung von Lungenveränderungen bei zystischer Fibrose in der nativen Lungen- MRT
- Author
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U Graepler-Mainka, J Schäfer, P Utz, L Kiefer, R Schwarz, M Esser, Mareen Sarah Kraus, and I Tsiflikas
- Published
- 2021
14. Impact of
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Lena Sophie, Kiefer, Julia, Sekler, Brigitte, Gückel, Mareen Sarah, Kraus, Christian, la Fougère, Konstantin, Nikolaou, Michael, Bitzer, Sergios, Gatidis, and Christina, Pfannenberg
- Subjects
Original Research - Abstract
Objective: To determine the impact of 18F-FDG-PET/CT on clinical management of patients with cholangiocellular carcinoma (CCA). Methods: Patients with CCA undergoing clinically indicated 18F-FDG-PET/CT between 04/2013 and 08/2018 were prospectively included in a local PET/CT registry study. Intended clinical management (“non-treatment” such as watchful-waiting or additional diagnostic tests, and “palliative” or “curative treatment”) was recorded before and after PET/CT. Changes in intended management after PET/CT were analyzed. Results: 27 patients (mean age: 60 years, IQR: 51.5–67.5 years, 56% males) with 43 PET/CT examinations were included. Intended management changed in 35/43 cases (81.4%) following PET/CT. Major changes (i.e., between “non-treatment” and “treatment” strategies or between a “curative” and “palliative” treatment goal) occurred in 27/43 (62.8%) cases. Before PET/CT, additional imaging and/or biopsy were intended in 21/43 (48.8%) and 9/43 (20.9%) cases, respectively. After PET/CT, further imaging was carried out in one case and imaging-targeted biopsy in eight cases. Although the absolute number of biopsies after PET/CT did not decrease, in only one of these eight cases biopsy had already been planned before PET/CT, whereas in the other eight cases, the originally planned biopsies were dispensable after PET/CT. Conclusions: 18F-FDG-PET/CT significantly impacts clinical management of patients with CCA. It guides decisions on treatment strategy (especially curative vs palliative treatment goal) and on additional tests, particularly by helping referring clinicians to avoid unnecessary imaging and by guiding targeted biopsy. Advances in knowledge: Systematic implementation of 18F-FDG-PET/CT may enable a more appropriate and tailored treatment of patients with CCA, especially in cases of suspected recurrence.
- Published
- 2021
15. Distribution patterns of intramyocellular and extramyocellular fat by magnetic resonance imaging in subjects with diabetes, prediabetes and normoglycaemic controls
- Author
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Thierno D. Diallo, Mareen Sarah Kraus, Lena S. Kiefer, Wolfgang Rathmann, Jürgen Machann, Susanne Rospleszcz, Jana Fabian, Christa Meisinger, Fabian Bamberg, Margit Heier, Christopher L. Schlett, Roberto Lorbeer, Frank W. Roemer, Konstantin Nikolaou, Annette Peters, and Corinna Storz
- Subjects
Male ,medicine.medical_specialty ,Endocrinology, Diabetes and Metabolism ,Population ,030209 endocrinology & metabolism ,Type 2 diabetes ,030204 cardiovascular system & hematology ,Gastroenterology ,Prediabetic State ,03 medical and health sciences ,0302 clinical medicine ,Endocrinology ,Diabetes mellitus ,Internal medicine ,Internal Medicine ,Humans ,Medicine ,Mass index ,ddc:610 ,Prediabetes ,Intramyocellular lipids ,Muscle, Skeletal ,education ,education.field_of_study ,business.industry ,Middle Aged ,medicine.disease ,Lipids ,Magnetic Resonance Imaging ,Diabetes Mellitus, Type 2 ,Body Composition ,Cohort Study ,Type 2 Diabetes ,Female ,Median body ,Intramuscular fat ,business ,human activities - Abstract
AIM To evaluate the distribution of intramyocellular lipids (IMCLs) and extramyocellular lipids (EMCLs) as well as total fat content in abdominal skeletal muscle by magnetic resonance imaging (MRI) using a dedicated segmentation algorithm in subjects with type 2 diabetes (T2D), prediabetes and normoglycaemic controls. MATERIALS AND METHODS Subjects from a population-based cohort were classified with T2D, prediabetes or as normoglycaemic controls. Total myosteatosis, IMCLs and EMCLs were quantified by multiecho Dixon MRI as proton-density fat-fraction (in %) in abdominal skeletal muscle. RESULTS Among 337 included subjects (median age 56.0 [IQR: 49.0-64.0] years, 56.4% males, median body mass index [BMI]: 27.2 kg/m2 ), 129 (38.3%) were classified with an impaired glucose metabolism (T2D: 49 [14.5%]; prediabetes: 80 [23.7%]). IMCLs were significantly higher than EMCLs in subjects without obesity (5.7% [IQR: 4.8%-7.0%] vs. 4.1% [IQR: 2.7%-5.8%], P
- Published
- 2021
16. Radiation Dose Optimization in Pediatric Chest CT: Major Indicators of Dose Exposure in 1695 CT Scans over Seven Years
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Michael Esser, Mareen Sarah Kraus, S. Schneeweiß, Juergen F. Schaefer, Sergios Gatidis, Ilias Tsiflikas, M Teufel, and Sabine Hess
- Subjects
Male ,Adolescent ,Iohexol ,Chest ct ,Contrast Media ,Radiation Dosage ,Effective dose (radiation) ,030218 nuclear medicine & medical imaging ,03 medical and health sciences ,0302 clinical medicine ,Germany ,Multidetector Computed Tomography ,Humans ,Medicine ,Radiology, Nuclear Medicine and imaging ,Child ,Retrospective Studies ,Univariate analysis ,business.industry ,Radiation dose ,Age Factors ,Infant, Newborn ,Infant ,Retrospective cohort study ,Equipment Design ,Cone-Beam Computed Tomography ,Radiation Exposure ,Image Enhancement ,Iopamidol ,Pediatric Radiology ,Child, Preschool ,030220 oncology & carcinogenesis ,Female ,Radiography, Thoracic ,Tomography ,Radiation protection ,Tomography, X-Ray Computed ,business ,Nuclear medicine - Abstract
To analyze possible influencing factors on radiation exposure in pediatric chest CT using different approaches for radiation dose optimization and to determine major indicators for dose development. In this retrospective study at a clinic with maximum care facilities including pediatric radiology, 1695 chest CT examinations in 768 patients (median age: 10 years; range: 2 days to 17.9 years) were analyzed. Volume CT dose indices, effective dose, size-specific dose estimate, automatic dose modulation (AEC), and high-pitch protocols (pitch ≥ 3.0) were evaluated by univariate analysis. The image quality of low-dose examinations was compared to higher dose protocols by non-inferiority testing. Median dose-specific values annually decreased by an average of 12 %. High-pitch mode (n = 414) resulted in lower dose parameters (p 0.001). In unenhanced CT, AEC delivered higher dose values compared to scans with fixed parameters (p 0.001). In contrast-enhanced CT, the use of AEC yielded a significantly lower radiation dose only in patients older than 16 years (p = 0.04). In the age group 6 to 15 years, the values were higher (p 0.001). The diagnostic image quality of low-dose scans was non-inferior to high-dose scans (2.18 vs. 2.14). Radiation dose of chest CT was reduced without loss of image quality in the last decade. High-pitch scanning was an independent factor in this context. Dose reduction by AEC was limited and only relevant for patients over 16 years.· The radiation dose of pediatric chest CT was reduced in the last decade.. · High-pitch scanning is an independent factor of dose optimization.. · Dose reduction by AEC is limited and only relevant for older children..· Esser M, Hess S, Teufel M et al. Radiation Dose Optimization in Pediatric Chest CT: Major Indicators of Dose Exposure in 1695 CT Scans over Seven Years. Fortschr Röntgenstr 2018; 190: 1131 - 1140.ZIEL: Analyse möglicher Einflussfaktoren auf die Strahlenexposition bei der Thorax-CT des Kindes unter Anwendung verschiedener Methoden der Dosisoptimierung und Bestimmung von Kenngrößen für die Dosisentwicklung. In dieser retrospektiven Studie an einer Klinik der Maximalversorgung einschließlich einer Abteilung für Kinderradiologie wurden 1695 Thorax-CTs von 768 Patienten (mittleres Alter, 10 Jahre; Spannweite, zwei Tage bis 17,9 Jahre) analysiert. Volumen-CT-Dosisindex, effektive Dosis und size-specific dose estimate, automatische Dosismodulation (AEC), sowie High-Pitch-Protokolle (Pitch ≥ 3,0) wurden mittels univariater Analyse ausgewertet. Die Bildqualität von Niedrigdosis-Untersuchungen wurde zu Protokollen mit höherer Dosis mittels „Non-Inferiority“-Analyse verglichen. Die medianen Dosiswerte sanken pro Jahr um durchschnittlich 12 %. Untersuchungen mit High-Pitch-Modus (n = 414) lieferten geringere Dosiswerte (p 0,001). In nativen Untersuchungen mit AEC ergaben sich höhere Dosiswerte im Vergleich zu Untersuchungen mit manuell festgelegten Parametern (p 0,001). In kontrastangehobenen CTs erzielte die AEC nur bei Patienten über 16 Jahren signifikant niedrigere Dosiswerte (p = 0,04). Im Alter von 6 bis 15 Jahren waren die Dosiswerte mit AEC höher (p 0,001). Die diagnostische Bildqualität von Niedrigdosis-Untersuchungen war den CTs mit höherer Dosis nicht unterlegen (2,18 vs. 2,14). Im letzen Jahrzehnt wurden die Dosiswerte der Thorax-CT ohne Verlust der Bildqualität reduziert. High-Pitch-Protokolle sind in diesem Zusammenhang ein unabhängiger Einflussfaktor. Die Dosisreduktion mittels AEC war beschränkt und nur für Patienten über 16 Jahren relevant.· Im letzten Jahrzehnt konnte die Strahlendosis der Thorax-CT bei Kindern reduziert werden.. · Die Untersuchung mit hohen Pitch-Werten ist ein unabhängiger Faktor der Dosisoptimierung.. · Die Dosisreduktion der AEC ist beschränkt und nur für ältere Kinder relevant..
- Published
- 2018
17. MR arthrography of the hip: diagnostic performance and image quality of 3D-steady state free precession versus 2D turbo spin echo sequences
- Author
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Joerg Hausdorf, Ulrich Grosse, Mareen Sarah Kraus, Sasan Partovi, Andrea Baur-Melnyk, Ahmed Sobieh, and Mike Notohamiprodjo
- Subjects
Adult ,Male ,musculoskeletal diseases ,medicine.medical_specialty ,Sensitivity and Specificity ,030218 nuclear medicine & medical imaging ,Arthroscopy ,03 medical and health sciences ,Imaging, Three-Dimensional ,0302 clinical medicine ,Positive predicative value ,Image Interpretation, Computer-Assisted ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Femur ,Pelvis ,Retrospective Studies ,medicine.diagnostic_test ,business.industry ,Magnetic resonance imaging ,Steady-state free precession imaging ,Middle Aged ,Magnetic Resonance Imaging ,Sagittal plane ,medicine.anatomical_structure ,030220 oncology & carcinogenesis ,Orthopedic surgery ,Female ,Artifacts ,business ,Nuclear medicine ,Hip Injuries - Abstract
To retrospectively compare the diagnostic performance of isotropic 3D steady-state free precession (3D-SSFP) sequences with 2D turbo spin-echo proton density-weighted fat-saturated (2D-TSE-PD fs) images in hip magnetic resonance arthrography; arthroscopy was a standard of reference. Eighty-one patients with suspected labral tears who underwent hip MR arthrography (3-T scanner) were included. 2D-TSE-PD fs sequences were acquired in three planes and a singular sagittal 3D-SSFP. Labral tears, cartilage pathology and bone marrow were independently assessed by two blinded radiologists using a 5-point Likert scale. Accuracy was determined in 39 patients using invasive arthroscopy. Diagnostic confidence of labral and cartilaginous pathologies based on image quality was rated higher for 3D-SSFP (4.5 ± 0.8; 4.35 ± 0.7; p
- Published
- 2018
18. MR Arthrography of the Hip: Diagnostic Performance and Image Quality of 3D Steady-State Free Precession versus 2D Turbo Spin-Echo Sequences
- Author
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Konstantin Nikolaou, Dominik Ketelsen, Mareen Sarah Kraus, Sasan Partovi, Roland Syha, Ulrich Grosse, Ahmed Sobieh, Mike Notohamiprodjo, and Joerg Hausdorf
- Subjects
medicine.medical_specialty ,Nuclear magnetic resonance ,Mr arthrography ,business.industry ,Image quality ,Medicine ,Radiology, Nuclear Medicine and imaging ,Orthopedics and Sports Medicine ,Radiology ,Steady state free precession ,Fast spin echo ,business - Published
- 2017
19. CT-morphologic and CT-textural patterns of response in inoperable soft tissue sarcomas treated with pazopanib—a preliminary retrospective cohort study
- Author
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Christian Philipp Reinert, Wolfgang M. Thaiss, Marius Horger, Gabriel C. C. Gast, Cristopher Kloth, Mareen Sarah Kraus, and Michael Esser
- Subjects
Adult ,Male ,medicine.medical_specialty ,Indazoles ,Treatment outcome ,Antineoplastic Agents ,Soft Tissue Neoplasms ,030218 nuclear medicine & medical imaging ,Pazopanib ,03 medical and health sciences ,0302 clinical medicine ,Text mining ,X ray computed ,medicine ,Carcinoma ,Humans ,Radiology, Nuclear Medicine and imaging ,Aged ,Retrospective Studies ,Aged, 80 and over ,Sulfonamides ,Full Paper ,business.industry ,Soft tissue ,Retrospective cohort study ,Sarcoma ,General Medicine ,Middle Aged ,medicine.disease ,Pyrimidines ,Treatment Outcome ,Pneumothorax ,030220 oncology & carcinogenesis ,Female ,Radiology ,business ,Tomography, X-Ray Computed ,medicine.drug - Abstract
Objective: To analyze patterns of response in soft tissue sarcomas exposed to pazopanib using CT-morphologic and textural features and their suitability for evaluating therapeutic response. Methods: Retrospective evaluation of CT response and texture patterns in 33 patients (23 female; mean age: 61.2 years, range, 30–85 years) with soft tissue sarcomas treated with pazopanib from October 2008 to July 2017. Response evaluation was based on modified (m)CHOI-criteria and RECISTv.1.1 and classified as partial response (PR), stable disease (SD), progressive disease (PD). The following CT-texture (CTTA)-parameters were calculated: mean, entropy and uniformity of intensity/average/skewness/entropy of co-occurrence matrix and contrast of neighboring-gray-level-dependence-matrix. Results: Following mCHOI-criteria, 12 patients achieved PR, 7 SD and 14 PD. As per RECISTv.1.1 9 patients obtained PR, 9 SD and 15 PD. Frequent patterns of response were tumor liquefaction and necrosis (n=4/33, 12.1% each). Further patterns included shrinkage and cavitation (n=2/33, 6.1% each). In responders, differences in mean heterogeneity (p=0.01), intensity (p=0.03), average (p=0.03) and entropy of skewness (p=0.01) were found at follow-up whereas in non-responders, CTTA-parameters did not change significantly. Baseline-CTTA-features differed between responders and non-responders in terms of uniformity of skewness (p=0.045). Baseline-CTTA-parameters did not correlate with any morphologic response pattern. Conclusion: Most frequent patterns of response to pazopanib were tumor liquefaction and necrosis. Single CT-textural features show strong association with the response to pazopanib—although limited in relation to specific response patterns. Advances in knowledge: Tumor liquefication and necrosis are important patterns of response to pazopanib. CT-texture analysis has limited associations with specific response patterns.
- Published
- 2019
20. New severity assessment in cystic fibrosis: signal intensity and lung volume compared to LCI and FEV
- Author
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Sabrina, Fleischer, Mareen Sarah, Kraus, Sergios, Gatidis, Winfried, Baden, Andreas, Hector, Dominik, Hartl, Ilias, Tsiflikas, and Juergen Frank, Schaefer
- Subjects
Adult ,Male ,Adolescent ,Cystic Fibrosis ,Respiration ,Organ Size ,Magnetic Resonance Imaging ,Severity of Illness Index ,Respiratory Function Tests ,Young Adult ,Exhalation ,Forced Expiratory Volume ,Humans ,Female ,Child ,Lung Volume Measurements ,Lung - Abstract
Magnetic resonance imaging (MRI) aids diagnosis in cystic fibrosis (CF) but its use in quantitative severity assessment is under research. This study aims to assess changes in signal intensity (SI) and lung volumes (Vol) during functional MRI and their use as a severity assessment tool in CF patients.The CF intra-hospital standard chest 1.5 T MRI protocol comprises of very short echo-time sequences in submaximal in- and expiration for functional information. Quantitative measurements (Vol/SI at in- and expiration, relative differences (Vol_delta/SI_delta), and cumulative histograms for normalized SI values across the expiratory lung volume) were assessed for correlation to pulmonary function: lung clearance index (LCI) and forced expiratory volume in 1 s (FEVIn 49 patients (26 male, mean age 17 ± 7 years) significant correlation of Vol_delta and SI_delta (R = 0.86; p0.0001) during respiration was observed. Individual cumulated histograms enabled severity disease differentiation (mild, severe) to be visualized (defined by functional parameter: LCI10). The expiratory volume at a relative SI of 100% correlated significantly to LCI (R = 0.676 and 0.627; p0.0001) and FEVFunctional pulmonary MRI provides a radiation-free severity assessment tool and can contribute to early detection of lung impairment in CF. Lung volume with SI below 100% of the inspiratory volume represents overinflated tissue; an amount of 4% of the expiratory lung volume was a relevant turning point.• Signal intensity and lung volumes are used as potential metric parameters for lung impairment. • Quantification of trapped air impacts on therapy management. • Functional pulmonary MRI can contribute to early detection of lung impairment.
- Published
- 2019
21. Impact of 18F-FDG-PET/CT on Clinical Management in Patients with Cholangiocellular Carcinoma
- Author
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Julia Sekler, Sergios Gatidis, B. Gückel, Lena S. Kiefer, Christina Pfannenberg, Michael Bitzer, Christian la Fougère, Konstantin Nikolaou, and Mareen Sarah Kraus
- Subjects
03 medical and health sciences ,medicine.medical_specialty ,0302 clinical medicine ,Cholangiocellular carcinoma ,business.industry ,030220 oncology & carcinogenesis ,Medicine ,Fdg pet ct ,In patient ,General Medicine ,Radiology ,business ,030218 nuclear medicine & medical imaging - Abstract
Objective: To determine the impact of 18F-FDG-PET/CT on clinical management of patients with cholangiocellular carcinoma (CCA). Methods: Patients with CCA undergoing clinically indicated 18F-FDG-PET/CT between 04/2013 and 08/2018 were prospectively included in a local PET/CT registry study. Intended clinical management (“non-treatment” such as watchful-waiting or additional diagnostic tests, and “palliative” or “curative treatment”) was recorded before and after PET/CT. Changes in intended management after PET/CT were analyzed. Results: 27 patients (mean age: 60 years, IQR: 51.5–67.5 years, 56% males) with 43 PET/CT examinations were included. Intended management changed in 35/43 cases (81.4%) following PET/CT. Major changes (i.e., between “non-treatment” and “treatment” strategies or between a “curative” and “palliative” treatment goal) occurred in 27/43 (62.8%) cases. Before PET/CT, additional imaging and/or biopsy were intended in 21/43 (48.8%) and 9/43 (20.9%) cases, respectively. After PET/CT, further imaging was carried out in one case and imaging-targeted biopsy in eight cases. Although the absolute number of biopsies after PET/CT did not decrease, in only one of these eight cases biopsy had already been planned before PET/CT, whereas in the other eight cases, the originally planned biopsies were dispensable after PET/CT. Conclusions: 18F-FDG-PET/CT significantly impacts clinical management of patients with CCA. It guides decisions on treatment strategy (especially curative vs palliative treatment goal) and on additional tests, particularly by helping referring clinicians to avoid unnecessary imaging and by guiding targeted biopsy. Advances in knowledge: Systematic implementation of 18F-FDG-PET/CT may enable a more appropriate and tailored treatment of patients with CCA, especially in cases of suspected recurrence.
- Published
- 2021
22. Diffusion kurtosis imaging histogram parameter metrics predicting survival in integrated molecular subtypes of diffuse glioma: An observational cohort study
- Author
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Franziska Eckert, Johann-Martin Hempel, Benjamin Bender, Mareen Sarah Kraus, Ulrike Ernemann, Georg Bier, Hardy Richter, Jens Schittenhelm, Marco Skardelly, Cornelia Brendle, and Uwe Klose
- Subjects
Oncology ,Adult ,Male ,medicine.medical_specialty ,World Health Organization ,030218 nuclear medicine & medical imaging ,03 medical and health sciences ,Diffuse Glioma ,0302 clinical medicine ,alpha-Thalassemia ,Internal medicine ,Glioma ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Diffusion Kurtosis Imaging ,ATRX ,Aged ,Retrospective Studies ,Univariate analysis ,Receiver operating characteristic ,Proportional hazards model ,business.industry ,Brain Neoplasms ,Univariate ,General Medicine ,Middle Aged ,medicine.disease ,Prognosis ,Isocitrate Dehydrogenase ,Diffusion Magnetic Resonance Imaging ,Diffusion Tensor Imaging ,030220 oncology & carcinogenesis ,Mental Retardation, X-Linked ,Female ,business ,Epidemiologic Methods ,Biomarkers - Abstract
The aim of the study was to assess the predictive value of preoperatively assessed diffusion kurtosis imaging (DKI) metrics as prognostic factors in the 2016 World Health Organization Classification of Tumors of the Central Nervous System integrated glioma groups.Seventy-seven patients with histopathologically confirmed treatment-naïve glioma were retrospectively assessed between 08/2013 and 10/2017 using mean kurtosis (MK) and mean diffusivity (MD) histogram parameters from DKI, overall and progression-free survival, and relevant prognostic molecular data (isocitrate dehydrogenase, [IDH]; alpha-thalassemia/mental retardation syndrome X-linked, [ATRX]; chromosome 1p/19q loss of heterozygosity). Receiver operating characteristic (ROC) analysis was performed on metric variables to determine the optimal cutoff-values. The Kaplan-Meier method was used to assess univariate survival data. A multivariate Cox proportional hazards model was performed on significant results from the univariate analysis.There were significant differences in overall and progression-free survival between patient age (p = 0.001), resection statuses (p = 0.002), WHO glioma grades (p 0.0001), and integrated molecular profiles (p 0.0001). Survival was significantly better in patients with lower MK and higher MD values globally (p = 0.009), in gliomas without chromosome 1p/19q LOH (p 0.0001), and those with retained ATRX expression (p = 0.008).Patient age and MK from DKI from DKI are relevant factors for preoperatively predicting overall and progression-free survival. Regarding the molecular subgroups, they seem to be predictive in gliomas with ATRX retention, representing a feature of IDH wild-type gliomas.
- Published
- 2018
23. Spinal dual-energy computed tomography: improved visualisation of spinal tumorous growth with a noise-optimised advanced monoenergetic post-processing algorithm
- Author
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Jakob Weiss, Nadja Selo, Konstantin Nikolaou, Mike Notohamiprodjo, Ahmed E. Othman, Fabian Bamberg, Mareen Sarah Kraus, and Thomas Flohr
- Subjects
Male ,Image quality ,media_common.quotation_subject ,Signal-To-Noise Ratio ,Sensitivity and Specificity ,030218 nuclear medicine & medical imaging ,Radiography, Dual-Energy Scanned Projection ,03 medical and health sciences ,0302 clinical medicine ,Image noise ,Medicine ,Image acquisition ,Contrast (vision) ,Humans ,Radiology, Nuclear Medicine and imaging ,In patient ,Spinal Cord Neoplasms ,media_common ,Neuroradiology ,Spinal Neoplasms ,business.industry ,Reproducibility of Results ,Dual-Energy Computed Tomography ,Middle Aged ,equipment and supplies ,Radiographic Image Enhancement ,030220 oncology & carcinogenesis ,Female ,Neurology (clinical) ,Cardiology and Cardiovascular Medicine ,business ,Nuclear medicine ,Artifacts ,Noise (radio) ,Algorithms - Abstract
The aim of this study was to evaluate the effect of advanced monoenergetic post-processing (MEI+) on the visualisation of spinal growth in contrast-enhanced dual-energy CT (DE-CT). Twenty-six oncologic patients (age, 61 ± 17 years) with spinal tumorous growth were included. Patients underwent contrast-enhanced dual-energy CT on a third-generation dual-source CT scanner. Image acquisition was in dual-energy mode (100/Sn150kV), and scans were initiated 90 s after contrast agent administration. Virtual monoenergertic images (MEI+) were reconstructed at four different kiloelectron volts (keV) levels (40, 60, 80, 100) and compared to the standard blended portal venous computed tomography (CTpv). Image quality was assessed qualitatively (conspicuity, delineation, sharpness, noise, confidence; two independent readers; 5-point Likert scale; 5 = excellent) and quantitatively by calculating signal-to-noise (SNR) and contrast-to-noise-ratios (CNR). For a subgroup of 10 patients with MR imaging within 4 months of the DE-CT, we compared the monoenergetic images to the MRIs qualitatively. Highest contrast of spinal growth was observed in MEI+ at 40 keV, with significant differences to CTpv and all other keV reconstructions (60, 80, 100; p
- Published
- 2016
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