10 results on '"Ro, Sa-Ra"'
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2. Tunneled hemodialysis catheter insertion: Above, within, or below the right atrium—Where is the tip?
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Auer, Jonas, primary, Braun, Joachim, additional, Lenk, Julian, additional, Gollrad, Johannes, additional, Ro, Sa-Ra, additional, Hamm, Bernd, additional, and de Bucourt, Maximilian, additional
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- 2022
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3. Impact of double reading on NI-RADS diagnostic accuracy in reporting oral squamous cell carcinoma surveillance imaging – a single-center study
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Elsholtz, Fabian Henry Jürgen, primary, Ro, Sa-Ra, additional, Shnayien, Seyd, additional, Dinkelborg, Patrick, additional, Hamm, Bernd, additional, and Schaafs, Lars-Arne, additional
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- 2022
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4. Retrospective Evaluation of NI-RADS for Detecting Postsurgical Recurrence of Oral Squamous Cell Carcinoma on Surveillance CT or MRI
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Dinkelborg, Patrick, primary, Ro, Sa-Ra, additional, Shnayien, Seyd, additional, Schaafs, Lars-Arne, additional, Koerdt, Steffen, additional, Kreutzer, Kilian, additional, Heiland, Max, additional, Hamm, Bernd, additional, and Elsholtz, Fabian Henry Jürgen, additional
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- 2021
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5. DCE-MR imaging of orbital lesions: diagnostic performance of the tumor flow residence time τ calculated by a multi-compartmental pharmacokinetic tumor model based on individual factors
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Erb-Eigner, Katharina, primary, Asbach, Patrick, additional, Ro, Sa-Ra, additional, Haas, Matthias, additional, Bertelmann, Eckart, additional, Pietsch, Hubertus, additional, Schwenke, Carsten, additional, Taupitz, Matthias, additional, Denecke, Timm, additional, Hamm, Bernd, additional, and Lawaczeck, Rüdiger, additional
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- 2018
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6. Multiparametrische Charakterisierung orbitaler Raumforderungen mittels Magnetresonanztomografie
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Ro, Sa-Ra
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multiparametric ,DWI ,DCE ,orbital masses ,600 Technik, Medizin, angewandte Wissenschaften::610 Medizin und Gesundheit ,MRI - Abstract
Einleitung Orbitale und intraokuläre Raumforderungen sind relativ selten und ihre Differenzierung in benigne und maligne gestaltet sich auf Grund ihrer ähnlichen Symptomatik und mangelnder diagnostischer Hilfsmittel oft problematisch. Ziel dieser Arbeit ist daher die Bewertung der diagnostischen Leistungsfähigkeit der multiparametrischen Magnetresonanztomografie (mpMRT) bei der Unterscheidung maligner von benignen orbitalen Raumforderungen. Material und Methoden An dieser prospektiven, durch die Ethikkommission der Charité – Universitätsmedizin Berlin zugelassenen Studie nahmen 65 Patienten teil, nachdem sie ausführlich aufgeklärt wurden und schriftlich eingewilligt hatten. Die mpMRT wurde an einem 3 Tesla-Gerät unter Verwendung von konventioneller (= anatomischer), diffusionsgewichteter (DWI) und dynamisch kontrastverstärkter (DCE) MR-Bildgebung durchgeführt. Der scheinbare Diffusionskoeffizient (ADC) wurde für jede Raumforderung berechnet. Zur Beurteilung der Permeabilität der Kapillargefäße wurden die Perfusionsparameter Ktrans (= Volumentransferrate vom Blutgefäß in den extravaskulären Extrazellularraum (EZR)), kep (= Flussrate vom extravaskulären EZR zurück ins Blutgefäß), ve (= Volumen des extravaskulären EZR bezogen auf das Volumen des veränderten Gewebes) und iAUC (= initiale Fläche unter der Gadolinium-Konzentrations-Kurve innerhalb der ersten 60 Sekunden) mittels parametrischer Karten generiert. Um das Kontrastmittelverhalten der jeweiligen Raumforderung zu bestimmen, wurden Zeit-Signalintensitäts-Kurven aufgezeichnet. Zwei Radiologen schätzten die MRT-Aufnahmen hinsichtlich der Dignität der jeweiligen Läsion auf einer fünfstufigen Likert-Skala in zwei getrennten Sitzungen ein (zunächst nur konventionelle Sequenzen, danach konventionelle und entweder DWI- oder DCE-Sequenzen). Die Daten wurden mittels Mann-Whitney U-Test und Pearson Chi² Test analysiert. Ergebnisse 33 Patienten hatten maligne orbitale Raumforderungen und 32 Patienten hatten benigne orbitale Raumforderungen (Referenzstandard: Histopathologie in 35 Fällen und klinisches Follow-up bei 30 Patienten). Der Mittelwert des ADC maligner Raumforderungen unterschied sich signifikant von dem Mittelwert (SD) des ADC benigner Raumforderungen (825,4 [437,2] x 10-6 mm²/s und 1257,8 [576,8] x 10-6 mm²/s) (p = 0,001). Ktrans, kep und iAUC zeigten in malignen Raumforderungen signifikant höhere Werte (p < 0,01). Benigne Raumforderungen zeigten höhere ve-Werte, während bei malignen Raumforderungen die ve-Werte niedriger waren. 25 bösartige Raumforderungen zeigten einen Washout-Kurvenverlauf, wohingegen 21 gutartige Raumforderungen einen persistierend steigenden Kurvenverlauf zeigten (p < 0,01). Die Analyse der konventionellen Sequenzen ergab eine moderate Spezifität und eine unbefriedigende Sensitivität. Durch Hinzunahme von DWI- bzw. DCE-Aufnahmen verbesserten sich Spezifität und Sensitivität deutlich. Schlussfolgerung DWI und DCE MR-Bildgebung unterstützen die Differenzierung orbitaler Raumforderungen in benigne und maligne und sollten daher in die Routinediagnostik orbitaler Raumforderungen aufgenommen werden., Introduction Orbital and intraocular masses are relatively uncommon and it is often difficult to differentiate malignant orbital masses from benign ones due to their similar clinical presentation and insufficient diagnostic tools. Hence, the purpose of this work was to evaluate the diagnostic performance of multiparametric magnetic resonance imaging (mpMRI) in distinguishing benign from malignant orbital masses. Material and methods This prospective IRB approved study with written informed consent included 65 patients. mpMRI at 3 Tesla including sAI (=standard anatomic imaging), DWI (=diffusion-weighted imaging) and DCE (=dynamic contrast enhanced MR imaging) was performed. Apparent diffusion coefficient (ADC) was calculated for each mass. To assess the capillary leakage parametric maps were generated for obtaining the perfusion parameters including Ktrans (= volume transfer constant between blood plasma and extravascular extracellular space (EES)), kep (= efflux rate constant from EES to blood plasma), ve (= EES volume per unit volume of tissue) and iAUC (= initial area under the gadolinium concentration curve during the first 60 s). Time-signal intensity curves were recorded to determine the curve pattern. Two radiologists estimated the likelihood of malignancy on a five-point Likert scale in two separate reading sessions (initially only sAI, afterwards sAI + either DWI or DCE). Data were analyzed using Mann-Whitney U test and Pearson Chi² test. Results 33 patients had malignant orbital masses and 32 patients had benign orbital masses (reference standard histopathology in 35 cases and clinical follow-up in 30 patients). The mean ADC of malignant masses differed significantly from the mean (SD) ADC of benign masses (825.4 [437.2] x 10-6 mm²/sec and 1257.8 [576.8] x 10-6 mm²/sec, respectively) (p = 0.001). Ktrans, kep and iAUC were significantly higher in malignant masses (p < 0.01). Benign masses demonstrated higher values while malignant lesions more often presented lower values of ve. 25 malignant masses showed a washout pattern and 21 benign masses showed a persistent pattern (p < 0.01). The reading of sAI resulted in an only moderate specificity and an unsatisfying sensitivity. Adding DWI and DCE images improved specificity and sensitivity considerably. Conclusion DWI and DCE MR imaging are helpful tools in differentiating malignant from benign orbital masses and should therefore be included in the routine diagnostic approach of orbital masses.
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- 2016
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7. DCE-MR imaging of orbital lesions: diagnostic performance of the tumor flow residence time τ calculated by a multi-compartmental pharmacokinetic tumor model based on individual factors.
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Erb-Eigner, Katharina, Asbach, Patrick, Ro, Sa-Ra, Haas, Matthias, Bertelmann, Eckart, Pietsch, Hubertus, Schwenke, Carsten, Taupitz, Matthias, Denecke, Timm, Hamm, Bernd, and Lawaczeck, Rüdiger
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CONTRAST-enhanced magnetic resonance imaging ,HOUSING ,RECEIVER operating characteristic curves ,DIFFERENTIAL diagnosis ,DIAGNOSTIC imaging ,EYE-sockets ,EYE-socket tumors ,HETEROCYCLIC compounds ,LONGITUDINAL method ,MAGNETIC resonance imaging ,ORGANOMETALLIC compounds ,RESEARCH evaluation ,TIME ,CONTRAST media - Abstract
Background: Differentiating benign from malignant orbital lesions by imaging and clinical presentation can be challenging.Purpose: To differentiate benign from malignant orbital masses using dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) based on tumor flow residence time τ calculated with the aid of a pharmacokinetic tumor model.Material and Methods: Sixty patients with orbital masses were investigated by 3-T MRI including dynamic sequences. The signal intensity-time curve after i.v. contrast medium administration within lesions was approximated by Gd-concentration profiles on the basis of model calculations where the tumor is embedded in a whole-body kinetic model. One output of the model was tumor flow residence time τ, defined as the ratio of the tumor volume and the tumor blood flow rate. Receiver operating characteristic (ROC) curves were used to analyze the diagnostic performance of τ. The results were compared with those of Ktrans, kep, ve, iAUC, and ADC.Results: Thirty-one benign and 29 malignant orbital masses were identified (reference standard: histopathology, clinical characteristics). Mean τ was significantly longer for benign masses (94 ± 48 s) than for malignant masses (21 ± 19 s, P < 0.001). ROC analysis revealed the highest area under the curve (AUC = 0.94) for τ in orbital masses compared to standard methods.Conclusion: Tumor flow residence times τ of benign and malignant orbital masses are valuable in the diagnostic work-up of orbital tumors. Measures of diagnostic accuracy were superior for τ compared to ADC, Ktrans, ve, and iAUC. [ABSTRACT FROM AUTHOR]- Published
- 2019
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8. Characterization of orbital masses by multiparametric MRI
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Ro, Sa-Ra, primary, Asbach, Patrick, additional, Siebert, Eberhard, additional, Bertelmann, Eckart, additional, Hamm, Bernd, additional, and Erb-Eigner, Katharina, additional
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- 2016
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9. Effects of oral contrast agent on the viscoelastic properties of the terminal ileum investigated using magnetic resonance elastography.
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Ro SR, Loch FN, Siegmund B, Kühl AA, Neumann GM, Hamm B, Braun J, Sack I, and Reiter R
- Abstract
Background: While standard clinical magnetic resonance (MR) enterography can detect inflammatory bowel disease, it is of limited value in deciding between medical versus surgical treatment. Alternatively, intestinal MR elastography has the potential to contribute additional information to therapeutic decision-making; however, the influence of bowel distension by oral contrast agent on viscoelastic tissue properties remains elusive. Therefore, we aimed to investigate the influence of oral contrast agent-induced bowel distension on the viscoelastic properties of the terminal ileum in healthy volunteers., Methods: In this prospective pilot study, 20 healthy volunteers (33.2±8.2 years; 10 men, 10 women) underwent multifrequency MR elastography using a single-shot spin-echo echo planar imaging sequence at 1.5 Tesla and drive frequencies of 40, 50, 60 and 70 Hz. Maps of shear wave speed ( c in ms
-1 ) and loss angle ( φ in rad), representing stiffness and viscous properties, respectively, were generated using tomoelastography data processing. The volunteers were scanned before and after ingestion of 1,000 mL of 2% mannitol solution as oral contrast agent., Results: There was no significant difference in terminal ileum biomechanical properties before vs. after ingestion of an oral contrast agent (mean c : 1.47±0.24 vs. 1.40±0.25 ms-1 with P=0.37; mean φ : 0.70±0.12 rad vs. 0.68±0.12 rad with P=0.61). Moreover, there was no statistically significant correlation between MR elastography parameters before and after the ingestion of oral contrast ( c : r =0.22, P=0.36; φ : r =0.24, P=0.30)., Conclusions: The results of this study suggest that bowel distension for intestinal MR elastography has no systematic effect on the biomechanical tissue properties of the terminal ileum determined by MR elastography. Therefore, future study protocols appear feasible with or without oral contrast agents., Competing Interests: Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://qims.amegroups.com/article/view/10.21037/qims-24-101/coif). B.S., A.A.K., B.H., J.B., I.S., and R.R. report that this study was funded by the German Research Foundation. B.H. is Grant recipient from Abbott, AbbVie, Ablative Solutions, Accovion, Achogen Inc., Actelion Pharmaceuticals, ADIR, Aesculap, Agios Pharmaceuticals, INC., AGO, Arbeitsgemeinschaft industrieller Forschungsvereinigungen, Arbeitsgemeinschaft internistische Onkologie, Aktionsbündnis Partnersicherheit e.V., Alexion Pharmaceuticals, Amgen, AO Foundation, Aravive, Arena Pharmaceuticals, ARMO Biosciences, Inc., Array Biopharma Inc., Art photonics GmbH Berlin, ASAS, Ascelia Pharma AB, Ascendis, Advanced sleep research, Astrellas, AstraZeneca, August Research OOF, Sofia, BG, BARD, Basiliea, Bayer Healthcare, Bayer Schering Pharma, Bayer Vital, BBraun, BerGenBioASA, Berlin-Brandenburger Centrum für regenerative Therapie, Berliner Krebsgesellschaft, Biontech Mainz, BioNTech SE, Biotronik, Bioven, BMBF, BMS, Boehring Ingelheimer, Boston Biomedical Inc., Boston Scientific Medizintechnik GmbH, BRACCO Group, Brahms GmbH, Brainsgate, Bistol-Myers Squibb, Calithera Biosciences UK, Cantargia AB, Medicon Village, Cascadian Therapeutics, Inc., Celgene, CELLACT Pharma, Celldex Therapeutics, Cellestia Biotech AG CH, CeloNova BioSciences, and Charité research organization GmbH. B.S. has served as consultant for Abbvie, Abivax, BMS, Boehringer, CED Service GmbH, Endpoint Health, Falk, Galapagos, Janssen, Lilly, Pfizer, Takeda, and Predictimmune; he received speaker fees from: AbbVie, BMS, CED Service GmbH, Falk, Ferring, Galapagos, Janssen, Lilly, Materia Prima, Takeda, Pfizer and grant support by Arena/Pfizer (served as representative of the Charité). The other authors have no conflicts of interest to declare., (2024 Quantitative Imaging in Medicine and Surgery. All rights reserved.)- Published
- 2024
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10. Retrospective Evaluation of NI-RADS for Detecting Postsurgical Recurrence of Oral Squamous Cell Carcinoma on Surveillance CT or MRI.
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Dinkelborg P, Ro SR, Shnayien S, Schaafs LA, Koerdt S, Kreutzer K, Heiland M, Hamm B, and Elsholtz FHJ
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- Female, Humans, Male, Middle Aged, Mouth diagnostic imaging, Mouth surgery, Mouth Neoplasms surgery, Retrospective Studies, Squamous Cell Carcinoma of Head and Neck surgery, Magnetic Resonance Imaging methods, Mouth Neoplasms diagnostic imaging, Neoplasm Recurrence, Local diagnostic imaging, Radiology Information Systems, Squamous Cell Carcinoma of Head and Neck diagnostic imaging, Tomography, X-Ray Computed methods
- Abstract
BACKGROUND. Imaging surveillance is important for the early diagnosis of recurrence after definitive treatment of oral squamous cell carcinoma (OSCC). The Neck Imaging Reporting and Data System (NI-RADS) includes a standardized template for surveillance imaging and categorizes probability of recurrence at the primary site and in the neck (cervical lymph nodes) by assigning categories of 1 (no evidence of recurrence), 2 (low suspicion, subdivided into 2a and 2b for the primary site), 3 (high suspicion), and 4 (definite recurrence). OBJECTIVE. The aim of this study was to determine the rate of locoregional and nodal OSCC recurrence stratified by NI-RADS category among patients undergoing surveillance CT or MRI. METHODS. This retrospective study included 158 patients enrolled in an institutional surveillance program after resection of OSCC with curative intent. A total of 503 contrast-enhanced CT or MRI examinations performed during surveillance were evaluated. Each examination was randomly assigned to one of four radiologists with expertise in head and neck imaging, who provided NI-RADS categories for the primary site and the neck (1006 assigned NI-RADS categories). NI-RADS performance in identifying recurrence was assessed by ROC curve analysis. All four readers evaluated 50 randomly assigned cases to determine interreader agreement by use of the Kendall W statistic. RESULTS. Cancer recurrence was confirmed in 7.6% (38/503) of cases for the primary site and in 6.2% (31/503) for the neck. For the primary site, recurrence rates were 1.0% in NI-RADS category 1, 7.1% in category 2a, 5.6% in category 2b, 66.7% in category 3, and 100.0% in category 4. For the neck, recurrence rates were 0.5% in category 1, 7.0% in category 2, 80.0% in category 3, and 100.0% in category 4. NI-RADS had AUC values of 0.934 for the primary site and 0.959 for the neck. Interreader agreement was 0.67 for the primary site and 0.81 for the neck. CONCLUSION. NI-RADS offers excellent discriminatory power in detection of OSCC recurrence, both for the primary site and the neck. CLINICAL IMPACT. Radiologists and maxillofacial surgeons should implement NI-RADS in surveillance regimens for postoperative OSCC to help detect recurrences in an effective and standardized manner using imaging.
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- 2021
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