11 results on '"Dethlefsen, Ebba"'
Search Results
2. Dedicated Photon-Counting CT for Detection and Classification of Microcalcifications: An Intraindividual Comparison With Digital Breast Tomosynthesis.
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Huck, Luisa Charlotte, Bode, Maike, Zanderigo, Eloisa, Wilpert, Caroline, Raaff, Vanessa, Dethlefsen, Ebba, Wenkel, Evelyn, and Kuhl, Christiane Katharina
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- 2024
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3. Feasibility study of 2D Dixon-Magnetic Resonance Fingerprinting (MRF) of breast cancer
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Zanderigo, Eloisa, Huck, Luisa, Distelmaier, Martina, Dethlefsen, Ebba, Maywald, Mirjam, Truhn, Daniel, Dirrichs, Timm, Doneva, Mariya, Schulz, Volkmar, Kuhl, Christiane K., and Nolte, Teresa
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- 2022
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4. Single-needle electroporation and interstitial electrochemotherapy: in vivo safety and efficacy evaluation of a new system
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Pedersoli, Federico, Ritter, Andreas, Zimmermann, Markus, Schulze-Hagen, Maximilian, Liebl, Martin, Dethlefsen, Ebba, von Stillfried, Saskia, Pfeffer, Joachim, Kuhl, Christiane K., Bruners, Philipp, and Isfort, Peter
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- 2019
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5. Phantom study for comparison between computed tomography- and C-Arm computed tomography-guided puncture applied by residents in radiology.
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Meine, Timo C., Hinrichs, Jan B., Werncke, Thomas, Afat, Saif, Biggemann, Lorenz, Bucher, Andreas, Büttner, Martina, Christner, Sara, Dethlefsen, Ebba, Engel, Hannes, Gerwing, Mirjam, Getzin, Tobias, Gräger, Stephanie, Gresser, Eva, Grunz, Jan-Peter, Harder, Felix, Heidenreich, Julius, Hitpaß, Lea, Jakobi, Kristina, and Janisch, Michael
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- 2022
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6. Loss of 4q21.23-22.1 Is a Prognostic Marker for Disease Free and Overall Survival in Non-Small Cell Lung Cancer.
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Uzunoglu, Faik G., Dethlefsen, Ebba, Hanssen, Annkathrin, Wrage, Michaela, Deutsch, Lena, Harms-Effenberger, Katharina, Vashist, Yogesh K., Reeh, Matthias, Sauter, Guido, Simon, Ronald, Bockhorn, Maximillian, Pantel, Klaus, Izbicki, Jakob R., and Wikman, Harriet
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BIOMARKERS , *SMALL cell lung cancer , *MICROSATELLITE repeats , *FLUORESCENCE in situ hybridization , *CANCER cells , *ONCOLOGIC surgery - Abstract
This study was performed to assess the prognostic relevance of genomic aberrations at chromosome 4q in NSCLC patients. We have previously identified copy number changes at 4q12-q32 to be significantly associated with the early hematogenous dissemination of non-small cell lung cancer (NSCLC), and now aim to narrow down potential hot-spots within this 107 Mb spanning region. Using eight microsatellite markers at position 4q12-35, allelic imbalance (AI) analyses were performed on a preliminary study cohort (n = 86). Positions indicating clinicopathological and prognostic associations in AI analyses were further validated in a larger study cohort using fluorescence in situ hybridization (FISH) in 209 NSCLC patients. Losses at positions 4q21.23 and 4q22.1 were shown to be associated with advanced clinicopathological characteristics as well as with shortened disease free (DFS) and overall survival (OS) (DFS: P = 0.019; OS: P = 0.002). Multivariate analyses identified the losses of 4q21.23-22.1 to be an independent prognostic marker for both DFS and OS in NSCLC (HR 1.64–2.20, all P<0.04), and especially in squamous cell lung cancer (P<0.05). A case report study of a lung cancer patient further revealed a loss of 4q21.23 in disseminated tumor cells (DTCs). Neither gains at the latter positions, nor genomic aberrations at 4q12, 4q31.2 and 4q35.1, indicated a prognostic relevance. In conclusion, our data indicate that loss at 4q21.23-22.1 in NSCLC is of prognostic relevance in NSCLC patients and thus, includes potential new tumor suppressor genes with clinical relevance. [ABSTRACT FROM AUTHOR]
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- 2014
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7. Detection of Microcalcifications in Spiral Breast Computed Tomography with Photon-Counting Detector Is Feasible: A Specimen Study.
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Wetzl, Matthias, Wenkel, Evelyn, Balbach, Eva, Dethlefsen, Ebba, Hartmann, Arndt, Emons, Julius, Kuhl, Christiane, Beckmann, Matthias W., Uder, Michael, Ohlmeyer, Sabine, and Pinker-Domenig, Katja
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CALCIFICATIONS of the breast ,TOMOSYNTHESIS ,TOMOGRAPHY ,DETECTORS ,BREAST biopsy - Abstract
The primary objective of the study was to compare a spiral breast computed tomography system (SBCT) to digital breast tomosynthesis (DBT) for the detection of microcalcifications (MCs) in breast specimens. The secondary objective was to compare various reconstruction modes in SBCT. In total, 54 breast biopsy specimens were examined with mammography as a standard reference, with DBT, and with a dedicated SBCT containing a photon-counting detector. Three different reconstruction modes were applied for SBCT datasets (Recon1 = voxel size (0.15 mm)
3 , smooth kernel; Recon2 = voxel size (0.05 mm)3 , smooth kernel; Recon3 = voxel size (0.05 mm)3 , sharp kernel). Sensitivity and specificity of DBT and SBCT for the detection of suspicious MCs were analyzed, and the McNemar test was used for comparisons. Diagnostic confidence of the two readers (Likert Scale 1 = not confident; 5 = completely confident) was analyzed with ANOVA. Regarding detection of MCs, reader 1 had a higher sensitivity for DBT (94.3%) and Recon2 (94.9%) compared to Recon1 (88.5%; p < 0.05), while sensitivity for Recon3 was 92.4%. Respectively, reader 2 had a higher sensitivity for DBT (93.0%), Recon2 (92.4%), and Recon3 (93.0%) compared to Recon1 (86.0%; p < 0.05). Specificities ranged from 84.7–94.9% for both readers (p > 0.05). The diagnostic confidence of reader 1 was better with SBCT than with DBT (DBT 4.48 ± 0.88, Recon1 4.77 ± 0.66, Recon2 4.89 ± 0.44, and Recon3 4.75 ± 0.72; DBT vs. Recon1/2/3: p < 0.05), while reader 2 found no differences. Sensitivity and specificity for the detection of MCs in breast specimens is equal for DBT and SBCT when a small voxel size of (0.05 mm)3 is used with an equal or better diagnostic confidence for SBCT compared to DBT. [ABSTRACT FROM AUTHOR]- Published
- 2021
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8. Potential of spiral breast computed tomography to increase patient comfort compared to DM.
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Wetzl, Matthias, Wenkel, Evelyn, Dietzel, Matthias, Siegler, Lisa, Emons, Julius, Dethlefsen, Ebba, Heindl, Felix, Kuhl, Christiane, Uder, Michael, and Ohlmeyer, Sabine
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DIGITAL mammography , *PATIENT compliance , *BODY mass index , *LIKERT scale , *PATIENTS' attitudes , *MAGNETIC resonance mammography , *SPIRAL computed tomography , *MAMMOGRAMS , *BREAST , *BREAST tumors , *LONGITUDINAL method - Abstract
Purpose: To intra-individually compare patient comfort of spiral breast computed tomography (SBCT) versus digital mammography (DM).Method: This prospective IRB approved study included 79 patients undergoing both SBCT and DM for the assessment of BI-RADS 4 - 6 lesions. Following SBCT and DM patients answered a standardized questionnaire regarding "Overall patient comfort" and "Pain" on a 5-point Likert Scale. On the same Likert Scale, experienced radiologic technicians rated the workflow of the SBCT regarding patients' "Mobility", ease of patient "Positioning", patients' adherence to the examination ("Compliance") and expected image quality. Visibility of fibroglandular tissue in SBCT was independently rated by two breast radiologists on a 10-point Likert Scale. Subgroups stratified by menopausal status and body mass index (BMI) were analyzed.Results: Patients reported significantly lower pain during SBCT (4.73 ± 0.57) compared to DM (4.09 ± 0.90; P < 0.01). This effect was independent from BMI. However, pain reduction by SBCT was most pronounced in premenopausal (SBCT vs. DM: 4.79 ± 0.50 vs. 3.89 ± 0.99) compared to postmenopausal patients (4.71 ± 0.77 vs. 4.20 ± 0.89). Overall patient comfort in premenopausal patients tended to be higher in SBCT compared to DM (P = 0.08). Radiologic technicians rated the SBCT procedure generally as positive (average: 4.62 ± 0.56). Coverage of fibroglandular tissue in SBCT was generally high (9.82 ± 0.43) and interrater agreement was good (κ = 0.77).Conclusions: Patients experience less pain during spiral breast computed tomography compared to DM, especially in premenopausal women. Imaging is feasible at a high level of anatomical breast coverage and without problems with the clinical workflow. [ABSTRACT FROM AUTHOR]- Published
- 2021
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9. Photon-counting versus Dual-Source CT of Congenital Heart Defects in Neonates and Infants: Initial Experience.
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Dirrichs T, Tietz E, Rüffer A, Hanten J, Nguyen TD, Dethlefsen E, and Kuhl CK
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- Adult, Infant, Newborn, Child, Humans, Male, Infant, Female, Child, Preschool, Signal-To-Noise Ratio, Thorax, Lung, Radiation Dosage, Tomography, X-Ray Computed methods, Heart Defects, Congenital diagnostic imaging
- Abstract
Background Photon-counting CT (PCCT) has been shown to improve cardiovascular CT imaging in adults. Data in neonates, infants, and young children under the age of 3 years are missing. Purpose To compare image quality and radiation dose of ultrahigh-pitch PCCT with that of ultrahigh-pitch dual-source CT (DSCT) in children suspected of having congenital heart defects. Materials and Methods This is a prospective analysis of existing clinical CT studies in children suspected of having congenital heart defects who underwent contrast-enhanced PCCT or DSCT in the heart and thoracic aorta between January 2019 and October 2022. CT dose index and dose-length product were used to calculate effective radiation dose. Signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were calculated by standardized region-of-interest analysis. SNR and CNR dose ratios were calculated. Visual image quality was assessed by four independent readers on a five-point scale: 5, excellent or absent; 4, good or minimal; 3, moderate; 2, limited or substantial; and 1, poor or massive. Results Contrast-enhanced PCCT ( n = 30) or DSCT ( n = 84) was performed in 113 children (55 female and 58 male participants; median age, 66 days [IQR, 15-270]; median height, 56 cm [IQR, 52-67]; and median weight, 4.5 kg [IQR, 3.4-7.1]). A diagnostic image quality score of at least 3 was obtained in 29 of 30 (97%) with PCCT versus 65 of 84 (77%) with DSCT. Mean overall image quality ratings were higher for PCCT versus DSCT (4.17 vs 3.16, respectively; P < .001). SNR and CNR were higher for PCCT versus DSCT with SNR (46.3 ± 16.3 vs 29.9 ± 15.3, respectively; P = .007) and CNR (62.0 ± 50.3 vs 37.2 ± 20.8, respectively; P = .001). Mean effective radiation doses were similar for PCCT and DSCT (0.50 mSv vs 0.52 mSv; P = .47). Conclusion At a similar radiation dose, PCCT offers a higher SNR and CNR and thus better cardiovascular imaging quality than DSCT in children suspected of having cardiac heart defects. © RSNA, 2023.
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- 2023
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10. Using Machine Learning to Reduce the Need for Contrast Agents in Breast MRI through Synthetic Images.
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Müller-Franzes G, Huck L, Tayebi Arasteh S, Khader F, Han T, Schulz V, Dethlefsen E, Kather JN, Nebelung S, Nolte T, Kuhl C, and Truhn D
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- Humans, Middle Aged, Retrospective Studies, Breast, Machine Learning, Contrast Media, Magnetic Resonance Imaging methods
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Background Reducing the amount of contrast agent needed for contrast-enhanced breast MRI is desirable. Purpose To investigate if generative adversarial networks (GANs) can recover contrast-enhanced breast MRI scans from unenhanced images and virtual low-contrast-enhanced images. Materials and Methods In this retrospective study of breast MRI performed from January 2010 to December 2019, simulated low-contrast images were produced by adding virtual noise to the existing contrast-enhanced images. GANs were then trained to recover the contrast-enhanced images from the simulated low-contrast images (approach A) or from the unenhanced T1- and T2-weighted images (approach B). Two experienced radiologists were tasked with distinguishing between real and synthesized contrast-enhanced images using both approaches. Image appearance and conspicuity of enhancing lesions on the real versus synthesized contrast-enhanced images were independently compared and rated on a five-point Likert scale. P values were calculated by using bootstrapping. Results A total of 9751 breast MRI examinations from 5086 patients (mean age, 56 years ± 10 [SD]) were included. Readers who were blinded to the nature of the images could not distinguish real from synthetic contrast-enhanced images (average accuracy of differentiation: approach A, 52 of 100; approach B, 61 of 100). The test set included images with and without enhancing lesions (29 enhancing masses and 21 nonmass enhancement; 50 total). When readers who were not blinded compared the appearance of the real versus synthetic contrast-enhanced images side by side, approach A image ratings were significantly higher than those of approach B (mean rating, 4.6 ± 0.1 vs 3.0 ± 0.2; P < .001), with the noninferiority margin met by synthetic images from approach A ( P < .001) but not B ( P > .99). Conclusion Generative adversarial networks may be useful to enable breast MRI with reduced contrast agent dose. © RSNA, 2023 Supplemental material is available for this article. See also the editorial by Bahl in this issue.
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- 2023
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11. Phantom study for comparison between computed tomography- and C-Arm computed tomography-guided puncture applied by residents in radiology.
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Meine TC, Hinrichs JB, Werncke T, Afat S, Biggemann L, Bucher A, Büttner M, Christner S, Dethlefsen E, Engel H, Gerwing M, Getzin T, Gräger S, Gresser E, Grunz JP, Harder F, Heidenreich J, Hitpaß L, Jakobi K, Janisch M, Kocher N, Kopp M, Lennartz S, Martin O, Moher Alsady T, Pamminger M, Pedersoli F, Piechotta PL, Platz Batista da Silva N, Raudner M, Roehrich S, Schindler P, Schwarze V, Seppelt D, Sieren MM, Spurny M, Starekova J, Storz C, Wiesmüller M, Zopfs D, Ringe KI, Meyer BC, and Wacker FK
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- Humans, Phantoms, Imaging, Punctures methods, Software, Radiology, Tomography, X-Ray Computed methods
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Purpose: Comparison of puncture deviation and puncture duration between computed tomography (CT)- and C-arm CT (CACT)-guided puncture performed by residents in training (RiT)., Methods: In a cohort of 25 RiTs enrolled in a research training program either CT- or CACT-guided puncture was performed on a phantom. Prior to the experiments, the RiT's level of training, experience playing a musical instrument, video games, and ball sports, and self-assessed manual skills and spatial skills were recorded. Each RiT performed two punctures. The first puncture was performed with a transaxial or single angulated needle path and the second with a single or double angulated needle path. Puncture deviation and puncture duration were compared between the procedures and were correlated with the self-assessments., Results: RiTs in both the CT guidance and CACT guidance groups did not differ with respect to radiologic experience (p = 1), angiographic experience (p = 0.415), and number of ultrasound-guided puncture procedures (p = 0.483), CT-guided puncture procedures (p = 0.934), and CACT-guided puncture procedures (p = 0.466). The puncture duration was significantly longer with CT guidance (without navigation tool) than with CACT guidance with navigation software (p < 0.001). There was no significant difference in the puncture duration between the first and second puncture using CT guidance (p = 0.719). However, in the case of CACT, the second puncture was significantly faster (p = 0.006). Puncture deviations were not different between CT-guided and CACT-guided puncture (p = 0.337) and between the first and second puncture of CT-guided and CACT-guided puncture (CT: p = 0.130; CACT: p = 0.391). The self-assessment of manual skills did not correlate with puncture deviation (p = 0.059) and puncture duration (p = 0.158). The self-assessed spatial skills correlated positively with puncture deviation (p = 0.011) but not with puncture duration (p = 0.541)., Conclusion: The RiTs achieved a puncture deviation that was clinically adequate with respect to their level of training and did not differ between CT-guided and CACT-guided puncture. The puncture duration was shorter when using CACT. CACT guidance with navigation software support has a potentially steeper learning curve. Spatial skills might accelerate the learning of image-guided puncture., Key Points: · The CT-guided and CACT-guided puncture experience of the RiTs selected as part of the program "Researchers for the Future" of the German Roentgen Society was adequate with respect to the level of training.. · Despite the lower collective experience of the RiTs with CACT-guided puncture with navigation software assistance, the learning curve regarding CACT-guided puncture may be faster compared to the CT-guided puncture technique.. · If the needle path is complex, CACT guidance with navigation software assistance might have an advantage over CT guidance.., Citation Format: · Meine TC, Hinrichs JB, Werncke T et al. Phantom study for comparison between computed tomography- and C-Arm computed tomography-guided puncture applied by residents in radiology. Fortschr Röntgenstr 2022; 194: 272 - 280., Competing Interests: Lorenz Biggemann: L. B. declares travel grant from Siemens Healthineers and speakers honorarium from Bristol Myer-Squibb unrelated to this project.Jan –Peter Grunz: J.-P. G. declares employment as “Research Consultant” at Siemens Healthineers unrelated to this project.Markus Kopp: M. B. declares participation at the Siemens Healthineers speakers’ bureau unrelated to this project.Simon Lennartz: S. L. declares institutional research support from Philips unrelated to this project.Timo C. Meine: T.C.M. declares passive participation at the BTG TheraSphere™ DACH Summit 2018 unrelated to this to this project.Bernhard C. Meyer: B.C.M. declares relationships with Siemens Healthcare and ProMedicus (outside the submitted work).Frank K. Wacker: F. K. W. declares relationships with Siemens Healthcare and ProMedicus (outside the submitted work).David Zopfs: D. Z. declares institutional research support from Philips Healthcare unrelated to this project., (Thieme. All rights reserved.)
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- 2022
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