104 results on '"Gehl HB"'
Search Results
2. Magnetartefakte nach Cochlea-Implantation - Intraindividueller Vergleich von Cochlea-Implantaten der zweiten und dritten Generation
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Kilgue, A, Eichler, T, Ibrahim, M, Gehl, HB, Sudhoff, H, Todt, I, Kilgue, A, Eichler, T, Ibrahim, M, Gehl, HB, Sudhoff, H, and Todt, I
- Published
- 2022
3. High resolution evaluation of various cochlear implant electrodes’ scalar position by 3T MRI
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Riemann, C, primary, Scholtz, LU, additional, Gehl, HB, additional, Sudhoff, H, additional, and Todt, I., additional
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- 2021
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4. MRI follow-up after intralabyrinthine and vestibular schwannoma resection and cochlear implantation
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Lauer, AC, additional, Sudhoff, H, additional, Gehl, HB, additional, Boga, E, additional, and Todt, I, additional
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- 2019
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5. MRT-Kontrollen nach Resektion intralabyrinthärer und vestibulärer Schwannome und Cochlea-Implantation
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Lauer, AC, additional, Sudhoff, H, additional, Gehl, HB, additional, Boga, E, additional, and Todt, I, additional
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- 2019
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6. Estimation of different cochlear implant electrodes position in the human temporal bone by high resolution 3T MRI
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Scholtz, LU, additional, Gehl, HB, additional, Sudhoff, H, additional, and Todt, I, additional
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- 2018
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7. Beurteilung unterschiedlicher Cochlea Implantelektroden und deren scalärer Position im humanen Felsenbein mittels hochauflösenden 3T MRT
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Scholtz, LU, additional, Gehl, HB, additional, Sudhoff, H, additional, and Todt, I, additional
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- 2018
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8. Das kindliche Lymphangiom als Differentialdiagnose einer plötzlich aufgetretenen cervicalen Schwellung
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Stoiber-Lipp, F, Reineke, U, Gehl, HB, Sudhoff, H, and Stolle, M
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ddc: 610 ,610 Medical sciences ,Medicine - Abstract
Einleitung: Die 5-jährige Patientin wurde von den Eltern notfallmäßig in unserer Klinik vorgestellt bei plötzlich, beim Spielen aufgetretener, schmerzloser, cervicaler Schwellung rechts. Z.n. Tonsillektomie und Adenotomie 10 Tage zuvor alio loco. Anamnese: Bei der Patientin wurde[for full text, please go to the a.m. URL], 83. Jahresversammlung der Deutschen Gesellschaft für Hals-Nasen-Ohren-Heilkunde, Kopf- und Hals-Chirurgie
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- 2012
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9. Mangan-Dipyridoxal-Diphosphat als neues Kontrastmittel in der MRT von benignen und malignen Pankreastumoren: Erste klinische Erfahrungen
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S Hauptmann, Rolf W. Günther, P. Klever, and Gehl Hb
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Pancreatic disease ,Side effect ,business.industry ,Urine ,medicine.disease ,Contrast medium ,medicine.anatomical_structure ,Flip angle ,Contrast-to-noise ratio ,medicine ,Radiology, Nuclear Medicine and imaging ,T2 weighted ,business ,Nuclear medicine ,Pancreas - Abstract
MnDPDP is a new intracellular contrast medium of which 50% is excreted through the bile; its acceptability and effect on MR images was studied in 21 patients, 18 of whom had malignant and three benign tumours of the pancreas. Spin echo T1 images (SE-T1: TR = 500 ms; TE = 15 ms) showed a 20% increase in signal to noise ratio (S/N) (p = 0.059) and a 90% increase in contrast to noise ratio (C/N) (p = 0.0027). In gradient T1 images (GE-T1: TR = 100 ms; TE = 6 ms; flip angle = 70 degrees) there was an increase of S/N of 70% (p < 0.0001) and of the C/N of 200% (p < 0.0001). T2 weighted SE sequences were inferior to plain SE-T1 weighted sequences with regard to their S/N and C/N ratios. There were no significant clinical complications or biochemical changes in the blood or urine. A subjective side effect in three patients was a feeling of heat. MnDPDP is a well tolerated and effective contrast medium for MRT of pancreatic tumours.
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- 1993
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10. Mn-DPDP in MR imaging of pancreatic adenocarcinoma: initial clinical experience
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Gehl Hb, V. Schumpelick, S. Matern, Bohndorf K, R Urhahn, Rolf W. Günther, S Hauptmann, K P Lodemann, and P. Klever
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Male ,Pathology ,medicine.medical_specialty ,Pancreatic disease ,Contrast Media ,Adenocarcinoma ,medicine ,Mangafodipir ,Humans ,Radiology, Nuclear Medicine and imaging ,Pancreas ,Edetic Acid ,Manganese ,medicine.diagnostic_test ,business.industry ,Pancreatic tissue ,Magnetic resonance imaging ,Middle Aged ,medicine.disease ,Magnetic Resonance Imaging ,Mr imaging ,Pancreatic Neoplasms ,medicine.anatomical_structure ,Hepatic parenchyma ,Pyridoxal Phosphate ,Female ,business ,Nuclear medicine ,medicine.drug - Abstract
Manganese (II) N,N'-dipyridoxylethylenediamine-N,N'-diacetate 5,5'-bis(phosphate) (DPDP) was tested as a contrast agent for magnetic resonance imaging of pancreatic adenocarcinoma in 15 patients. At enhanced T1-weighted spin-echo (SE) and enhanced T1-weighted gradient-echo (GRE) imaging, statistically significant increases in signal-to-noise ratio (S/N) for the pancreas (21% and 92%, respectively) and contrast-to-noise ratio (C/N) (91% and 209%, respectively) were found. The C/N at enhanced T1-weighted SE imaging was superior to that at unenhanced imaging, including T2-weighted SE imaging (P = .001). Subjective image analysis showed that delineation of the pancreas and pancreatic tumors was clearly improved (P = .05) on enhanced T1-weighted SE and GRE images compared with on unenhanced T1- and T2-weighted images. The liver enhanced 19% at T1-weighted SE imaging and 90% at T1-weighted GRE imaging. There was a significantly higher S/N increase in hepatic parenchyma than in pancreatic tissue at enhanced T1-weighted GRE imaging (P = .0026) but not at enhanced T1-weighted SE imaging.
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- 1993
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11. MR-Angiographie (MRA) der tiefen Bein- und Beckenvenenthrombose: Vergleich mit der Phlebographie
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Rolf W. Günther, Gehl Hb, and Bohndorf K
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medicine.medical_specialty ,medicine.diagnostic_test ,business.industry ,Deep vein ,medicine.disease ,Thrombosis ,Inferior vena cava ,medicine.anatomical_structure ,medicine.vein ,Angiography ,cardiovascular system ,Internal iliac vein ,Medicine ,Radiology, Nuclear Medicine and imaging ,cardiovascular diseases ,Pelvic vein thrombosis ,Radiology ,business ,Pelvis ,Gradient echo - Abstract
MRA by means of flow-phased gradient echo sequences is a valuable addition to phlebography for showing the extent of thrombosis in the veins of the pelvis and lower limbs. In eight out of 32 patients in whom the extent of deep vein thrombosis was not clearly shown by phlebography, it was possible to demonstrate the involvement of the inferior vena cava. Three of these patients had bilateral pelvic vein thrombosis. In seven out of 32 cases, thrombosis on the opposite side, which was not apparent clinically, could be demonstrated by MRA. Seven out of 32 patients showed involvement of the internal iliac vein. MRA is also valuable for observing the effect of treatment.
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- 1990
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12. Renal perfusion imaging using contrast-enhanced phase-inversion ultrasound
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Bergmann-Köster Cu, Stöckelhuber Bm, Kreft B, Gehl Hb, Wiesmann M, and Stöckelhuber M
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Nephrology ,Adult ,Graft Rejection ,Male ,medicine.medical_specialty ,Kidney Cortex ,media_common.quotation_subject ,Contrast Media ,Perfusion scanning ,Kidney ,Renal Circulation ,Internal medicine ,medicine ,Contrast (vision) ,Humans ,media_common ,Ultrasonography ,Kidney Medulla ,business.industry ,Ultrasound ,General Medicine ,Kidney Transplantation ,Transplantation ,medicine.anatomical_structure ,Kidney Failure, Chronic ,Female ,Radiology ,Nuclear medicine ,business ,Perfusion ,Phase inversion - Abstract
We evaluated different techniques of contrast-enhanced phase-inversion ultrasound to visualize renal perfusion in native kidneys and kidney transplants.Contrast-enhanced phase inversion ultrasound with different levels of mechanical index and frame rate was performed in 20 kidneys of 13 healthy volunteers. In addition, five dysfunctioning kidneys of patients with chronic renal failure, five functionally intact kidney transplants, three kidney transplants with compensated renal failure, and two kidney transplants with acute rejection were studied. Analysis using a software algorithm for time-resolved perfusion imaging was compared to single-image analysis performed by three independent radiologists.Optimal depiction of renal perfusion was achieved only by using a mechanical index, which was high enough to destroy the microbubbles of the contrast agent (burst imaging) combined with a low frame rate (0.5 images/second). Renal cortex and medulla showed a homogeneous enhancement in kidneys of healthy volunteers and functionally intact renal transplants. Dysfunctioning kidneys of patients with chronic renal failure as well as kidney transplants with compensated renal failure or acute rejection showed a significantly reduced level of enhancement. Computer-assisted time-resolved perfusion analysis was not superior to single-image analysis.Renal perfusion patterns of normal and abnormal tissue can be visualized using contrast-enhanced phase-inversion ultrasound imaging.
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- 2005
13. Eine weiße Raumforderung der Paukenhöhle - ein Vestibularisschwannom
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Stolle, MKW, Abdel-Aziz, T, Ebmeyer, J, Gehl, HB, Sudhoff, H, Stolle, MKW, Abdel-Aziz, T, Ebmeyer, J, Gehl, HB, and Sudhoff, H
- Published
- 2011
14. Pancreatic enhancement after low-dose infusion of Mn-DPDP
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K C Klose, Dierk Vorwerk, Rolf W. Günther, and Gehl Hb
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Male ,Time Factors ,Contrast Media ,Nuclear magnetic resonance ,Long period ,medicine ,Mangafodipir ,Humans ,Radiology, Nuclear Medicine and imaging ,Infusions, Intravenous ,Pancreas ,Edetic Acid ,Manganese ,medicine.diagnostic_test ,business.industry ,Low dose ,Mangafodipir trisodium ,Magnetic resonance imaging ,Image enhancement ,Image Enhancement ,Magnetic Resonance Imaging ,Mr imaging ,medicine.anatomical_structure ,Liver ,Pyridoxal Phosphate ,Nuclear medicine ,business ,medicine.drug - Abstract
Enhancement of the pancreas was demonstrated after low-dose (10 mumol/kg) infusion of a new contrast agent for magnetic resonance (MR) imaging, manganese dipyridoxal-diphosphate (Mn-DPDP). To the authors' knowledge, this has not been described previously. The enhancement reached a maximum of 98% +/- 13% (standard deviation) during a long period (greater than 6 hours). Mn-DPDP seems to have potential as a selective contrast agent in MR imaging of the pancreas.
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- 1991
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15. Schwannom des Taschenbandes - Fallbericht
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Ebmeyer, J, Reineke, U, Essing, M, Gehl, HB, Raute-Kreinsen, U, Sudhoff, H, Ebmeyer, J, Reineke, U, Essing, M, Gehl, HB, Raute-Kreinsen, U, and Sudhoff, H
- Published
- 2009
16. MRI findings in acute hypertensive encephalopathy
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Christoph Härtel, S. Schilling, Jürgen Sperner, and Gehl Hb
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Pediatrics ,medicine.medical_specialty ,Hypertensive encephalopathy ,business.industry ,MEDLINE ,Streptococcus infection ,medicine.disease ,Epilepsy ,Neurology ,medicine ,Neurology (clinical) ,Intensive care medicine ,business ,Mri findings - Published
- 2003
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17. Imaging of hemodialysis fistulas: limitations of MR angiography
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Klaus Bohndorf, Ulrich Gladziwa, Gehl Hb, Susanne Handt, and Rolf W. Günther
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Adult ,medicine.medical_specialty ,medicine.medical_treatment ,Anastomosis ,Arteriovenous Shunt, Surgical ,Renal Dialysis ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Aged ,medicine.diagnostic_test ,business.industry ,Mr angiography ,Angiography, Digital Subtraction ,Digital subtraction angiography ,Middle Aged ,Magnetic Resonance Imaging ,Feeding artery ,Doppler sonography ,Forearm ,Regional Blood Flow ,Angiography ,cardiovascular system ,Hemodialysis ,Radiology ,business ,Shunt (electrical) ,Blood Flow Velocity - Abstract
The clinical feasibility and utility of a three-dimensional (3D) MR angiography (MRA) were evaluated in 20 patients with hemodialysis fistulas. All patients had well functioning shunts and were imaged with a fast imaging in steady precision (FISP) flow rephased and flow dephased sequence. For comparison digital subtraction angiography and color-coded image directed Doppler sonography were used. Of 20 patients studied, 4 interrupted the MR examination due to pain in the shoulder of the extremity imaged. Of the 16 remaining fistulas only 2 were completely displayed on MR including feeding artery, anastomosis, and draining vein(s) on the MRA. Although 15 of 16 feeding arteries were shown by MRA, 10 of 16 draining veins and 14 of 16 anastomoses of the fistulas showed signal voids due to a lack of rephasing. Superimposing the MRA on the dephased images helped to demonstrate the shunt in another four patients having normal shunts. Thus, the utility of 3D MRA in imaging of hemodialysis fistulas is limited by technical problems and by patient's cooperation.
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- 1991
18. Two-dimensional MR angiography in the evaluation of abdominal veins with gradient refocused sequences
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Bohndorf K, Rolf W. Günther, Gehl Hb, and K. C. Klose
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medicine.medical_specialty ,Vena Cava, Inferior ,Constriction, Pathologic ,Mesenteric Veins ,Mesenteric Vascular Occlusion ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Vein ,medicine.diagnostic_test ,business.industry ,Portal Vein ,Ultrasound ,Mr angiography ,Magnetic resonance imaging ,Thrombosis ,Middle Aged ,medicine.disease ,Magnetic Resonance Imaging ,Abdominal veins ,medicine.anatomical_structure ,Splenic Vein ,Angiography ,Abdomen ,Radiology ,business - Abstract
The purpose of this study was to demonstrate the potential role of gradient refocused magnetic resonance imaging as an angiographic method in the evaluation of abdominal veins. Fifteen patients with different venous disorders were examined using first order motion refocused gradient echo sequences (fast low angle shot) in sequential section acquisition technique. Twelve patients had abdominal tumors and three idiopathic thrombosis of abdominal veins. Magnetic resonance was superior to indirect splenoportography and mesentericoportography in evaluation of the abdominal veins in 8 of 10 cases. It was also superior to ultrasound in 3 of 7 cases and to dynamic CT in 2 of 11 cases. This resulted from a higher intrinsic contrast between flowing blood and stationary tissue. It is concluded that two-dimensional gradient refocused imaging may be a valuable angiographic method in the evaluation of abdominal veins.
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- 1990
19. Strahlenschutz in der kardialen MultiSlice CT
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Gellißen, J, primary, Schulz, E, additional, Leibecke, T, additional, Gehl, HB, additional, and Stoeckelhuber, BM, additional
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- 2004
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20. Spektrum und Strahlenexposition der CT-Fluoroskopie
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Stoeckelhuber, B, primary, Schulz, E, additional, Gellissen, J, additional, Melchert, UH, additional, Gehl, HB, additional, Bergmann-Koester, CU, additional, and Leibecke, T, additional
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- 2004
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21. Scimitar-Syndrom in der MRT
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Bock Ta, Krasny R, Gehl Hb, and Ch. Müller-Leisse
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business.industry ,Scimitar syndrome ,Medicine ,Radiology, Nuclear Medicine and imaging ,business ,Nuclear medicine ,medicine.disease - Published
- 1990
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22. Simultaneous ipsilateral epidermoid of the petrous apex combined with intracanalicular and extracanalicular facial schwannoma.
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Ebmeyer J, Gehl HB, Reineke U, Sudhoff H, Ebmeyer, Jörg, Gehl, Hans-Björn, Reineke, Ulf, and Sudhoff, Holger
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- 2009
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23. Vestibular schwannoma presenting as a white middle ear mass behind an intact tympanic membrane.
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Ebmeyer J, Gehl HB, Upile T, and Sudhoff HH
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- 2011
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24. Multicenter, double-blind, randomized, intraindividual crossover comparison of gadobenate dimeglumine and gadopentetate dimeglumine for Breast MR imaging (DETECT Trial)
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Antonella Petrillo, Matthieu Faivre-Pierret, Paolo Belli, K.-F. Kreitner, Francesco Sardanelli, Federica Pediconi, L. Martincich, Johannes T. Heverhagen, Pietro Panizza, Marco Salvatore, Claudia M. Weiss, Katja C. Siegmann, Fiona J. Gilbert, Chiara Zuiani, Stefano Corcione, Christian M. Zechmann, Hans B. Gehl, Harrie C. M. van den Bosch, Wei Jun Peng, Felix Diekmann, Lin Ma, Martincich, L, Faivre Pierret, M, Zechmann, Cm, Corcione, S, van den Bosch, Hc, Peng, Wj, Petrillo, A, Siegmann, Kc, Heverhagen, Jt, Panizza, P, Gehl, Hb, Diekmann, F, Pediconi, F, Ma, L, Gilbert, Fj, Sardanelli, F, Belli, P, Salvatore, Marco, Kreitner, Kf, Weiss, Cm, and Zuiani, C.
- Subjects
Adult ,Gadolinium DTPA ,China ,Contrast Media ,Breast Neoplasms ,Sensitivity and Specificity ,law.invention ,Double blind ,breast neoplasm, contrast media, MRI ,Breast cancer ,Meglumine ,breast neoplasm ,Randomized controlled trial ,Double-Blind Method ,law ,Predictive Value of Tests ,Image Interpretation, Computer-Assisted ,medicine ,Organometallic Compounds ,Humans ,Radiology, Nuclear Medicine and imaging ,Prospective Studies ,Prospective cohort study ,GADOBENATE DIMEGLUMINE ,Aged ,Aged, 80 and over ,Chi-Square Distribution ,Cross-Over Studies ,business.industry ,Middle Aged ,medicine.disease ,Mr imaging ,Crossover study ,Magnetic Resonance Imaging ,Europe ,Female ,Breast disease ,Nuclear medicine ,business ,MRI - Abstract
To intraindividually compare 0.1 mmol/kg doses of gadobenate dimeglumine and gadopentetate dimeglumine for contrast material-enhanced breast magnetic resonance (MR) imaging by using a prospective, multicenter double-blind, randomized protocol.Institutional review board approval and patient informed consent were obtained. One hundred sixty-two women (mean age, 52.8 years ± 12.3 [standard deviation]) enrolled at 17 sites in Europe and China between July 2007 and May 2009 underwent at least one breast MR imaging examination at 1.5 T by using three-dimensional spoiled gradient-echo sequences. Of these, 151 women received both contrast agents in randomized order in otherwise identical examinations separated by more than 2 but less than 7 days. Images, acquired at 2-minute or shorter intervals after contrast agent injection, were evaluated independently by three blinded radiologists unaffiliated with enrollment centers. Histopathologic confirmation was available for all malignant lesions (n = 144), while benign lesions were confirmed either by using histopathologic examination (n = 52) or by at least 12-month diagnostic follow-up (n = 20) with mammography and/or ultrasonography. Determinations of malignant lesion detection rates and diagnostic performance (sensitivity, specificity, accuracy, positive predictive value [PPV], and negative predictive value [NPV]) were performed and compared (McNemar and Wald tests). A full safety assessment was performed.Significant superiority for gadobenate dimeglumine was noted by readers 1, 2, and 3 for malignant lesion detection rate (91.7%, 93.1%, 94.4% vs 79.9%, 80.6%, 83.3%, respectively; P ≤ .0003). Readers 1, 2, and 3 reported significantly superior diagnostic performance (sensitivity, specificity, and accuracy) for breast cancer detection with gadobenate dimeglumine (91.1%, 94.5%, 95.2% vs 81.2%, 82.6%, 84.6%; 99.0%, 98.2%, 96.9% vs 97.8%, 96.9%, 93.8%; 98.2%, 97.8%, 96.7% vs 96.1%, 95.4%, 92.8%, respectively; P ≤ .0094) and significantly superior PPV (91.1%, 85.2%, 77.2% vs 80.7%, 75.5%, 60.9%, respectively; P ≤ .0002) and NPV (99.0%, 99.4%, 99.4% vs 97.8%, 98.0%, 98.1%, respectively; P ≤ .0003). No safety concerns were noted with either agent.Gadobenate dimeglumine is superior to gadopentetate dimeglumine for breast cancer diagnosis. © RSNA, 2010 Clinical trial registration no. NCT00486473 (http://www.clinicaltrials.gov/).http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.10100968/-/DC1.
- Published
- 2010
25. MRI-Based Inner Ear Assessment and Cochlin Tomoprotein-Based Evaluation of Perilymphatic Fistula in Patients with Sudden Hearing Loss.
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Kim R, Mihailovic D, Riemann C, Kilgué A, Pfeiffer CJ, Gehl HB, Scholtz LU, and Todt I
- Abstract
Objectives: To study the correlation between positive cochlin tomoprotein testing (CTP), magnetic resonance (MR) imaging, and the auditory and vestibular function amongst patients with sudden hearing loss., Study Design: Prospective case series., Methods: We prospectively examined eight patients who presented with sudden hearing loss (>60 dB) with or without vertigo or tinnitus. We performed an ELISA-based CTP detection test using middle ear lavage samples. In addition to the CTP examination, a magnetic resonance imaging (MRI) examination was performed using different sequences (T1 and a T1 sequence with a contrast medium (CM), a T2 sequence, 4 h delayed intravenous gadolinium-enhanced three-dimensional fluid-attenuated inversion recovery (3D FLAIR))., Results: All patients with sudden hearing loss (>60 dB) presented a non-specific contrast enhancement in the cochlea and vestibulum on the affected side on delayed 3D-FLAIR MRI. Four patients had a positive CTP test, suggesting a perilymphatic fistula (PLF). However, no specific MRI signal for a PLF was observed., Conclusions: Using multimodal diagnostic measures, such as CTP testing and different MRI sequences, no correlation could be found in patients with a PLF.
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- 2024
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26. Endolymphatic Hydrops Magnet Resonance Imaging in Ménière's Disease Patients after Cochlea Implantation.
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Pfeiffer CJ, Gehl HB, Scholtz LU, Goon P, Sudhoff H, and Todt I
- Abstract
Introduction: Cochlear implantation in patients with Ménière's disease (MD) is the treatment of choice in cases of functional deafness. Additional vertigo control is of central importance in this group of patients. Endolymphatic hydrops (ELH) is the pathophysiological correlate of MD and can be evaluated by magnet resonance imaging (MRI). Bilateral MD occurs in 10-33% and can be the reason for a postoperative persisting or newly occurring vertigo in this group. Recent developments in the field of implant magnets and experience in MRI sequences allow the diagnostic performance of MRI in cochlear implantees to be evaluated. The aim of the present study was to evaluate the possibility of MRI as a visual diagnostic tool for endolymphatic hydrops in cochlear implantees., Material and Methods: This was a retrospective study including three cochlear implantees (age: 61-76 years, one female, two male) suffering from MD who, postoperatively, had a recurrence of vertigo with Ménière's-like symptoms. An MRI was performed for the evaluation of ELH (ELH-MRI). MRI observation was performed by a 4 h iv. delayed Gad 3 D Flair sequence., Results: In all cases, the ipsilateral implant magnet artifact covered the vestibulum, the semicircular canals and the cochlea. The contralateral vestibulum, the semicircular canal and the cochlea were fully observable, and a classification of the ELH-MRI could be performed., Conclusion: ELH-MRI scanning allows for the detection of contralateral labyrinthine endolymphatic hydrops and is a tool for the postoperative evaluation of vertigo in cochlear implantees.
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- 2023
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27. Prospective Evaluation of 3 T MRI Effect on Residual Hearing Function of Cochlea Implantees.
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Eichler T, Ibrahim A, Riemann C, Scholtz LU, Gehl HB, Goon P, Sudhoff H, and Todt I
- Abstract
Introduction: The approval process for MRI safety of implants includes physical observations and an experimental evaluation in artificial settings to simulate the in vivo effect. This contains the observation of temperature changes and artificial current generation by the magnetic field. From these findings, the safety of an implant and its effect on the patient can be estimated. MRI safety is based on an in vivo evaluation of adverse events after the approval process, but an actual analysis of the effect on different tissues is not followed. The effect of MRI scanning in cochlea implantees on their residual hearing as the correlate of the hair cell function is so far unknown, therefore the aim of the present study was to observe the effect of 3 T MRI on the residual hearing of cochlea implantees., Material and Methods: In this prospective study, we performed a 3 T MRI T2 2D MS Drive sequence in eight cochlea-implanted ears. Before and after the MRI scan, a bone conduction pure tone audiogram (BC PTA) was performed. All cochlea implantees had a pre-scanning threshold of low frequency residual hearing between 20 dB and 65 dB., Results: Low frequency mean residual hearing was not affected by the 3 T T2 2D MS Drive sequence. We observed a pre-scanning threshold at 250 Hz of 42.9 (SD 3.9) dB and for 500 Hz 57.1 (SD 6.4) dB. Post-scanning BC PTA was for 250 Hz 42.1 (SD 3.9) dB and for 500 Hz 57.1 (SD 5.7) dB., Conclusion: 3 T MRI scanning has no significant functional effect on the hair cells in cochlea implantees in low frequencies with a T2 2D MS Drive sequence.
- Published
- 2022
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28. Ipsilateral Vestibular Schwannoma after Cochlear Implantation.
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Tüpker S, Ay N, Scholtz LU, Gehl HB, Mautner VF, Goon P, Sudhoff H, and Todt I
- Abstract
Objective: The vestibular schwannoma incidence rate is approximately 4.2 per 100,000/year. Thus far, about 700,000 cochlear implantations have been performed worldwide; therefore, the occurrence of vestibular schwannoma postcochlear implantations can be assumed to be infrequent. Recent developments allow safe observation and surveillance of the implanted-side internal auditory canal (IAC) and cochlea by magnetic resonance imaging (MRI), even after cochlear implantation. Patients . A 71-year-old woman with sudden hearing loss and a contralateral vestibular schwannoma without clinical and genetic signs of neurofibromatosis type II. Intervention(s) . Ipsilateral cochlear implantation and contralateral vestibular schwannoma extirpation with regular tumor follow-up. Main Outcome Measure(s) . Comparison of ipsilateral pre and postcochlear implantation 3T MRI T1 GAD., Results: We observed a tumor growing at the fundus of the internal auditory canal 1 year after cochlear implantation on the ipsilateral side. Although first detected after cochlear implantation beside a known vestibular schwannoma on the contralateral side, a scan slice thickness of 2 mm cannot fully exclude the preoperative persistence of a small tumor. Based on the clinical findings and after genetic exclusion of NFII, the patient was classified as a NFII mosaic type., Conclusion: Even after cochlear implantation, tumors in the IAC causing vertigo, facial palsy, and affecting the audiologic outcome can be detected by MRI. The MRI slice thickness used before cochlear implantation should be under 2 mm., Competing Interests: The authors declare that they have no conflicts of interest., (Copyright © 2022 S. Tüpker et al.)
- Published
- 2022
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29. Evaluation of cochlear implant electrode scalar position by 3 Tesla magnet resonance imaging.
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Riemann C, Scholtz LU, Gehl HB, Schürmann M, Sudhoff H, and Todt I
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- Humans, Magnetic Resonance Imaging, Magnets, Prospective Studies, Cochlear Implantation methods, Cochlear Implants, Electrodes, Implanted
- Abstract
The estimation of scalar electrode position is a central point of quality control during the cochlear implant procedure. Ionic radiation is a disadvantage of commonly used radiologic estimation of electrode position. Recent developments in the field of cochlear implant magnets, implant receiver magnet position, and MRI sequence usage allow the postoperative evaluation of inner ear changes after cochlear implantation. The aim of the present study was to evaluate the position of lateral wall and modiolar cochlear implant electrodes using 3 T MRI scanning. In a prospective study, we evaluated 20 patients (10× Med-El Flex 28; 5× HFMS AB and 5× SlimJ AB) with a 3 T MRI and a T2 2D Drive MS sequence (voxel size: 0.3 × 0.3 × 0.9 mm) for the estimation of the intracochlear position of the cochlear implant electrode. In all cases, MRI allowed a determination of the electrode position in relation to the basilar membrane. This observation made the estimation of 19 scala tympani electrode positions and a single case of electrode translocation possible. 3 T MRI scanning allows the estimation of lateral wall and modiolar electrode intracochlear scalar positions., (© 2021. The Author(s).)
- Published
- 2021
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30. Quality Control after Intracochlear Intralabyrinthine Schwannoma Resection and Cochlear Implantation.
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Sudhoff H, Scholtz LU, Gehl HB, and Todt I
- Abstract
Background: The combination of intralabyrinthine schwannoma (ILS) removal and cochlear implantation is the standard of care after surgical resection for audiological rehabilitation. Intracochlear ILS is not only the most frequent tumor in this group of schwannomas, but it is also, to some degree, surgically the most challenging because of its position behind the modiolus. Recent developments in the knowledge of implant position, implant magnet choice, and magnetic resonance imaging (MRI) sequences make an MRI follow-up after surgical removal possible. Thus far, no results are known about the surgical success and residual rate of these kind of tumors. The aim of the present study was to perform an early MRI follow-up for the evaluation of residual or recurrent intracochlear ILS after surgical removal and cochlear implantation., Methods: In a retrospective study, we evaluated seven patients after an intracochlear ILS removal and single-stage cochlear implantation with a mean period of 13.4 months post surgery with a 3T T1 GAD 2 mm sequence for a residual ILS. Patients were operated on using an individualized technique concept., Results: In six out of seven cases, 3 T T1 GAD 2 mm MRI follow-up showed no residual or recurrent tumor. In one case, a T1 signal indicated a tumor of the upper inner auditory canal (IAC) at the MRI follow up., Conclusion: MRI follow-up as a quality control tool after ILS removal and cochlear implantation is highly important to exclude residual tumors. Long-term MRI evaluation results are needed and can be obtained under consideration of implant position, implant magnet, and MRI sequence choice. A preoperative MRI slice thickness less than 2 mm can be recommended to visualize possible modiolar and IAC expansion.
- Published
- 2021
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31. Effect of head position on cochlear implant MRI artifact.
- Author
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Ay N, Gehl HB, Sudhoff H, and Todt I
- Subjects
- Artifacts, Humans, Magnetic Resonance Imaging, Magnets, Cochlear Implants, Ear, Inner diagnostic imaging, Ear, Inner surgery
- Abstract
Purpose: A new generation of cochlear implant (CI) magnets and specific surgical techniques (e.g., implant positioning) has changed the relationship between a CI and magnet resonance imaging (MRI). MRI allows a pain free in vivo evaluation of the inner ear fluid state and internal auditory canal after the insertion of an electrode. The aim of this study is to evaluate how the patient's head position in the MRI scanner influences the CI magnet-related artefact., Methods: We performed in vivo measurement of MRI artefacts at 3 T with a CI system containing a bipolar diametrical magnet. The implant magnet was positioned with a head bandage at different positions from the nasion and external auditory canal in three volunteers. We used a turbo spin echo (TSE) T2w sequence on the axial and coronal planes and observed three positions: (1) regular position, (2) chin to chest (anteflexion), and (3) hyperextension (retroflexion)., Results: By comparing the positions, anteflexion of the cervical spine in a chin-to-chest position allowed us to place the artefact in a more apical position from the IAC in the coronal plane. The hyperextension of the cervical spine position shifts the artefact father towards the cochlea's direction., Conclusion: The head's position can influence the location of MRI artefacts. In cases where the artefact diminished the IAC or cochlea, anteflexion of the cervical spine in the chin-to-chest position of the head in the MRI scanner should be attempted to allow a visualization of the IAC.
- Published
- 2021
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32. Laterality of Audiovestibular Symptoms Predicts Laterality of Endolymphatic Hydrops in Hydropic Ear Disease (Menière).
- Author
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Gürkov R, Todt I, Jadeed R, Sudhoff H, and Gehl HB
- Subjects
- Contrast Media, Edema, Humans, Magnetic Resonance Imaging, Retrospective Studies, Endolymphatic Hydrops diagnostic imaging, Meniere Disease
- Abstract
Background: For clinical confirmation of the diagnosis of hydropic ear disease (HED) (Menière) by MR imaging, two routes of contrast enhancement of the perilymphatic space are currently being used: intratympanic and intravenous. While unilateral intratympanic contrast application generally enables a higher perilymph signal intensity and image quality, the intravenous route allows for imaging of both inner ears simultaneously. It is conceivable that intratympanic contrast application to one ear would result in a failure to detect endolymphatic hydrops in a given patient if the hydrops is present only in the other ear. Therefore, in this study we examined the question whether the ear with the greater degree of endolymphatic hydrops may be predicted based on clinical features., Methods: Retrospective study of 50 patients with HED confirmed on MR imaging. Three tesla MR imaging with 3D fluid attenuated inversion recovery 4 hours after intravenous gadolinium contrast application was used to detect endolymphatic hydrops. The index ear was defined by auditory symptoms during attacks, low frequency hearing loss, and caloric canal paresis., Results: In all patients the ear with more severe symptoms corresponded with the ear showing the more severe hydrops on MR imaging., Conclusion: In summary, in this study population the degree of low-frequency hearing loss (250 Hz-1 kHz) in combination with auditory symptoms during attacks identified the ear with the greater extent of endolymphatic hydrops in all patients. In conclusion, intratympanic contrast application to the index ear seems to be sufficient to confirm the diagnosis of HED (Menière) on MR imaging.
- Published
- 2020
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33. MRI Observation After Intralabyrinthine and Vestibular Schwannoma Resection and Cochlear Implantation.
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Sudhoff H, Gehl HB, Scholtz LU, and Todt I
- Abstract
Objective: MRI observation is part of the regular follow-up after vestibular schwannoma (VS) or intralabyrinthine schwannoma (ILS) resection. Because cochlear implantation (CI) after resection is part of the audiological rehabilitation process, the magnet resonance imaging (MRI) behavior of CI systems needs to be considered. In light of recent developments in MRI artifact positioning and pain prevention, this study evaluates reproducible MRI observations after tumor resection and CI surgery as part of follow-up. Methods: In a retrospective study, we evaluated 9 patients with a T1 KM, T2 sequence MRI observation, and cone beam computed tomography (CBCT) after ILS/VS resection and CI. In all but one case, a CI with a diametrically bipolar magnet and a receiver positioned 8-9 cm behind the external auditory canal was performed. Results: In all but one case, MRI observation allowed for a pain-free visual assessment of the intralabyrinthine and internal auditory canal (IAC) regions. In one case, a painful dislodgement of the receiver magnet occurred. Conclusion: MRI follow-up after ILS and VS resection and CI is reproducibly possible. Implant choice and positioning should be considered before implantation to allow for a pain-free visual assessment afterward. This finding allows for the first time a widening of the indication into this patient group., (Copyright © 2020 Sudhoff, Gehl, Scholtz and Todt.)
- Published
- 2020
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34. Comparison of Cochlear Implant Magnets and Their MRI Artifact Size.
- Author
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Todt I, Guerkov R, Gehl HB, and Sudhoff H
- Subjects
- Artifacts, Humans, Cochlear Implants, Ear, Inner diagnostic imaging, Magnetic Resonance Imaging standards, Magnets
- Abstract
Introduction: Recent developments regarding cochlear implant magnets (e.g., a bipolar diametral magnet) and refined surgical techniques (e.g., implant positioning) have had a significant impact on the relation between cochlear implants and MRIs, making the reproducible visibility of cochlea and IAC possible. MRI scanning has changed from a contraindication to a diagnostic tool. Magnet artifact size plays a central role in the visual assessment of the cochlea and IAC., Objective: The aim of this study is to compare the CI magnet-related maximum artifact sizes of various cochlea implant systems., Materials and Methods: We performed an in vivo measurement of MRI artifacts at 1.5 and 3 Tesla with three cochlear implant magnet systems (AB 3D, Medel Synchrony, and Oticon ZTI). The implant, including the magnet, was positioned with a head bandage 7.0 cm and 120° from the nasion, external auditory canal. We used a TSE T2w MRI sequence on the axial and coronal plains and compared the artifacts in two volunteers for each tesla strength., Results: Intraindividual artifact size differences between the three magnets are smaller than interindividual maximum artifact size differences. 3 T MRI scans, in comparison to 1.5 T MRI scans, show a difference between soft artifact areas., Conclusion: We observed no major difference between maximum implant magnet artifact sizes of the three implant magnet types., Competing Interests: The authors declare that they have no conflicts of interest., (Copyright © 2020 I. Todt et al.)
- Published
- 2020
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35. [A rare pathology of the petrous part of the temporal bone: adenoma of the middle ear].
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Sudhoff H, Gehl HB, Brasch F, Riemann R, and Todt I
- Subjects
- Ear, Middle, Endoscopy, Female, Humans, Middle Aged, Temporal Bone, Adenoma diagnosis, Adenoma pathology, Adenoma therapy, Ear Neoplasms diagnosis, Ear Neoplasms pathology, Ear Neoplasms therapy
- Abstract
Adenomas are very rare tumors of the middle ear. They are benign neoplasms originating from the glandular components of the mucous membrane of the middle ear. The middle ear adenoma was first described by Hyams and Michaels in 1976, which was named an adenomatous tumor. This article reports the case of a 50-year-old female patient, who presented with recurrent right-sided dull otalgia and pulse synchronous tinnitis, which began 1 year prior to presentation, with the suspected diagnosis of a glomus tympanicum tumor. Following the otorhinolaryngological examination and imaging an unclear mesotympanal space-occupying lesion was detected. A transmeatal endoscopic complete removal of the tumor was carried out. The histopathological investigations enabled the diagnosis of an adenoma of the middle ear. Adenomas are a rare differential diagnosis of tumors of the middle ear. In cases with a suitable localization an adequate exposure and removal of this rare tumor can be achieved by a transmeatal endoscopic access.
- Published
- 2020
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36. 3T MRI-based estimation of scalar cochlear implant electrode position.
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Tek F, MüLler S, Boga E, Gehl HB, Seitz D, Scholtz LU, Sudhoff H, and Todt I
- Subjects
- Cochlea diagnostic imaging, Cochlea surgery, Cochlear Implantation instrumentation, Humans, Prospective Studies, Scala Tympani diagnostic imaging, Cochlear Implantation methods, Cochlear Implants, Electrodes, Implanted, Magnetic Resonance Imaging methods
- Published
- 2019
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37. Patient radiation dose in percutaneous biliary interventions: recommendations for DRLs on the basis of a multicentre study.
- Author
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Schmitz D, Vogl T, Nour-Eldin NA, Radeleff B, Kröger JC, Mahnken AH, Ittrich H, Gehl HB, Plessow B, Böttcher J, Tacke J, Wispler M, Rosien U, Schorr W, Joerdens M, Glaser N, Fuchs ES, Tal A, Friesenhahn-Ochs B, Leimbach T, Höpner L, Weber M, Gölder S, Böhmig M, Hetjens S, Rudi J, and Schegerer A
- Subjects
- Adult, Female, Humans, Male, Biliary Tract Surgical Procedures methods, Fluoroscopy statistics & numerical data, Germany, Radiography, Interventional statistics & numerical data, Reference Values, Retrospective Studies, Stents, Biliary Tract diagnostic imaging, Radiation Dosage, Radiation Exposure statistics & numerical data, Radiology, Interventional standards, Radiology, Interventional statistics & numerical data
- Abstract
Objective: Percutaneous biliary interventions (PBIs) can be associated with a high patient radiation dose, which can be reduced when national diagnostic reference levels (DRLs) are kept in mind. The aim of this multicentre study was to investigate patient radiation exposure in different percutaneous biliary interventions, in order to recommend national DRLs., Methods: A questionnaire asking for the dose area product (DAP) and the fluoroscopy time (FT) in different PBIs with ultrasound- or fluoroscopy-guided bile duct punctures was sent to 200 advanced care hospitals. Recommended national DRLs are set at the 75th percentile of all DAPs., Results: Twenty-three facilities (9 interventional radiology depts. and 14 gastroenterology depts.) returned the questionnaire (12%). Five hundred sixty-five PBIs with 19 different interventions were included in the analysis. DAPs (range 4-21,510 cGy·cm
2 ) and FTs (range 0.07-180.33 min) varied substantially depending on the centre and type of PBI. The DAPs of initial PBIs were significantly (p < 0.0001) higher (median 2162 cGy·cm2 ) than those of follow-up PBIs (median 464 cGy·cm2 ). There was no significant difference between initial PBIs with ultrasound-guided bile duct puncture (2162 cGy·cm2 ) and initial PBIs with fluoroscopy-guided bile duct puncture (2132 cGy·cm2 ) (p = 0.85). FT varied substantially (0.07-180.33 min)., Conclusions: DAPs and FTs in percutaneous biliary interventions showed substantial variations depending on the centre and the type of PBI. PBI with US-guided bile duct puncture did not reduce DAP, when compared to PBI with fluoroscopy-guided bile duct puncture. National DRLs of 4300 cGy·cm2 for initial PBIs and 1400 cGy·cm2 for follow-up PBIs are recommended., Key Points: • DAPs and FTs in percutaneous biliary interventions showed substantial variations depending on the centre and the type of PBI. • PBI with US-guided bile duct puncture did not reduce DAP when compared to PBI with fluoroscopy-guided bile duct puncture. • DRLs of 4300 cGy·cm2 for initial PBIs (establishing a transhepatic tract) and 1400 cGy·cm2 for follow-up PBIs (transhepatic tract already established) are recommended.- Published
- 2019
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38. Stapes Prosthesis Length: One Size Fits All?
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Sudhoff H, Gehl HB, Boga E, Müller S, Wilms K, Mutze S, and Todt I
- Subjects
- Female, Humans, Imaging, Three-Dimensional, Incus diagnostic imaging, Male, Retrospective Studies, Tomography, X-Ray Computed, Ossicular Prosthesis, Otosclerosis surgery, Stapes diagnostic imaging, Stapes Surgery methods, Vestibule, Labyrinth diagnostic imaging
- Abstract
Background: The insertion of the stapes piston into the vestibule provides the physical basis for a successful stapedotomy. In routine clinical practice, two different ways to handle prosthesis length are performed: (1) an individualized measurement of the stapes prosthesis length or (2) a standard prosthesis length for all cases., Objective: The objective of this study was to compare both ways of handling prosthesis length and the effect of these methods on insertional prosthesis depth., Material and Method: We retrospectively evaluated 39 patients after performing a stapedotomy for radiologically estimated vestibular stapes prosthesis insertion depth. The individual measured length data were hypothetically changed to a standard length of 4.75, 5, 5.25, and 5.5 mm, and the insertion depths were compared., Results: The individually measured prosthesis lengths led to an insertion depth between 0.2 and 1.6 mm (mean 0.74 mm). The ratio of insertion depth/vestibular depth was between 8 and 59.1% (mean 26.6%). The different assumed standard lengths led to different rates of the vestibulum positions and possible bony contacts at the vestibulum floor., Conclusion: The individual measurement led to a zero rate of the vestibulum positions of stapes prosthesis pistons with a low insertion depth/vestibular depth ratio., (© 2019 S. Karger AG, Basel.)
- Published
- 2019
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39. Comparison of gadobenate dimeglumine-enhanced breast MRI and gadopentetate dimeglumine-enhanced breast MRI with mammography and ultrasound for the detection of breast cancer.
- Author
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Gilbert FJ, van den Bosch HC, Petrillo A, Siegmann K, Heverhagen JT, Panizza P, Gehl HB, Pediconi F, Diekmann F, Peng WJ, Ma L, Sardanelli F, Belli P, Corcione S, Zechmann CM, Faivre-Pierret M, and Martincich L
- Subjects
- Contrast Media, Female, Humans, Image Enhancement methods, Middle Aged, Reproducibility of Results, Sensitivity and Specificity, Breast Neoplasms diagnosis, Gadolinium DTPA, Magnetic Resonance Imaging methods, Meglumine analogs & derivatives, Organometallic Compounds, Ultrasonography, Mammary methods
- Abstract
Purpose: To compare gadobenate dimeglumine-enhanced magnetic resonance imaging (MRI) with gadopentetate dimeglumine-enhanced MRI, mammography, and ultrasound for breast cancer detection across different malignant lesion types and across different densities of breast tissue., Materials and Methods: In all, 153 women with Breast Imaging Reporting and Data System (BI-RADS) 3–5 findings on mammography and/or ultrasound underwent identical breast MRI exams at 1.5T with gadobenate dimeglumine and gadopentetate dimeglumine. Images were evaluated by three independent blinded radiologists. Mammography, ultrasound, and combined mammography and/or ultrasound findings were available for 108, 109, and 131 women. Imaging findings were matched with histology data by a fourth, independent, blinded radiologist. Malignant lesion detection rates and diagnostic performance were compared., Results: In all, 120, 120, and 140 confirmed malignant lesions were present in patients undergoing MRI+mammography, MRI+ultrasound, and MRI+mammography and/or ultrasound, respectively. Significantly greater cancer detection rates were noted by all three readers for comparisons of gadobenate dimeglumine-enhanced MRI with mammography (Δ15.8–17.5%; P < 0.0001), ultrasound (Δ18.3–20.0%; P < 0.0001), and mammography and/or ultrasound (Δ8.6–10.7%; P ≤ 0.0105) but not for comparisons of gadopentetate dimeglumine-enhanced MRI with conventional techniques (P > 0.05). The false-positive detection rates were lower on gadobenate dimeglumine-enhanced MRI than on conventional imaging (4.0–5.5% vs. 11.1% at mammography; 6.3–8.4% vs. 15.5% at ultrasound). Significantly improved cancer detection on MRI was noted in heterogeneously dense breast (91.2–97.3% on gadobenate dimeglumine-enhanced MRI vs. 77.2–84.9% on gadopentetate dimeglumine-enhanced MRI vs. 71.9-84.9% with conventional techniques) and for invasive cancers (93.2–96.2% for invasive ductal carcinoma [IDC] on gadobenate dimeglumine-enhanced MRI vs. 79.7–88.5% on gadopentetate dimeglumine-enhanced MRI vs. 77.0–84.4% with conventional techniques). Overall diagnostic performance for the detection of cancer was superior on gadobenate dimeglumine-enhanced MRI than on conventional imaging or gadopentetate dimeglumine-enhanced MRI., Conclusion: Gadobenate dimeglumine-enhanced MRI significantly improves cancer detection compared to gadopentetate dimeglumine-enhanced MRI, mammography, and ultrasound in a selected group of patients undergoing breast MRI for preoperative staging or because of inconclusive findings at conventional imaging.
- Published
- 2014
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40. Computed tomography before balloon Eustachian tuboplasty--a true necessity?
- Author
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Abdel-Aziz T, Schröder S, Lehmann M, Gehl HB, Ebmeyer J, and Sudhoff H
- Subjects
- Balloon Occlusion, Humans, Postoperative Complications prevention & control, Predictive Value of Tests, Preoperative Care, Retrospective Studies, Temporal Bone diagnostic imaging, Temporal Bone surgery, Treatment Failure, Eustachian Tube diagnostic imaging, Eustachian Tube surgery, Otologic Surgical Procedures methods, Tomography, X-Ray Computed methods
- Abstract
Objective: Since the introduction of balloon Eustachian tuboplasty the necessity of preoperative high-resolution CT scans of the temporal bone has been a topic of debate. This study investigated the informative value of preoperative CT scanning in predicting intraoperative or postoperative difficulties and complications. Special focus was laid on the existence of carotid canal dehiscences for fear of intraprocedural injury., Study Design: Retrospective., Setting: Tertiary referral center., Patients and Interventions: Approximately 284 patients (510 Eustachian tubes) with intractable Eustachian tube dysfunction undergoing unilateral or bilateral balloon Eustachian tuboplasty with preoperative high-resolution CT scans of the temporal bone from January 1, 2009, to December 31, 2012., Results: Carotid canal dehiscences were found in 18 patients (6.3%). In 3 patients (4 Eustachian tubes, 1.1% of patients) balloon dilatation could not be performed because of difficulties advancing the balloon catheter. Of these 3 patients, one had bilateral carotid canal dehiscences, whereas the other two had unremarkable CT scans. Postoperative complications occurred in 3 patients (1.1%): 2 soft tissue emphysemas and 1 unilateral hypoglossal paresis. All 3 patients had unremarkable CT scans, and all complications resolved completely without further sequelae., Conclusion: Preoperative high-resolution CT scan of the temporal bone does not seem to be suitable to predict intraoperative or postoperative difficulties of balloon Eustachian tuboplasty. Being extremely cautious during balloon catheter insertion into the Eustachian tube and using a device that is designed with a built-in stop mechanism preventing too deep insertion, the data presented suggest that fear of injury to the internal carotid artery during balloon dilatation might be disproportionate. Nevertheless, for inexperienced surgeons, HR-CT scans of the temporal bone may help to understand the relation between internal carotid artery and the Eustachian tube.
- Published
- 2014
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41. Computed tomographic angiography imaging and clinical implications of internal mammary artery perforator vessels as recipient vessels in autologous breast reconstruction.
- Author
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Fansa H, Schirmer S, Cervelli A, and Gehl HB
- Subjects
- Adult, Angiography methods, Female, Humans, Middle Aged, Tomography, X-Ray Computed methods, Transplantation, Autologous, Treatment Outcome, Wound Healing physiology, Mammaplasty methods, Mammary Arteries diagnostic imaging, Mammary Arteries surgery, Perforator Flap blood supply
- Abstract
The internal mammary artery (IMA) is the standard recipient vessel for autologous breast reconstruction. To save the IMA for bypass surgery, to keep flap pedicles short, and to allow better flap positioning, the IMA perforators were used. Forty-six flaps for immediate breast reconstructions were performed in 39 patients. In the first 22 patients, the decision to use the perforators was clinically based. In the second group of 17 patients, all patients received a thoracic computed tomographic angiography (CTA) to determine the perforators. In 13 flaps (6 deep inferior epigastric artery perforator, 3 superficial inferior epigastric artery, and 4 transverse myocutaneous gracilis), the perforators were used as recipient vessels. Of these flaps, 5 were anastomosed to perforators before the CTA was applied and 8 after the CTA was established. The CTA revealed the IMA and the perforators in detail. In immediate reconstructions, the IMA perforators can be used as recipient vessels. They allow better flap positioning for superficial inferior epigastric artery and transverse myocutaneous gracilis flaps in particular; moreover, it decreases donor site and recipient site morbidity. After introducing the CTA, the perforators were used more frequently for anastomosis.
- Published
- 2013
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42. Multimodality treatment for poorly differentiated neuroendocrine head and neck carcinomas--a single institution experience.
- Author
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Görner M, Brasch F, Hirnle P, Gehl HB, Scholtz LU, Wegehenkel K, and Sudhoff H
- Subjects
- Adult, Aged, Carboplatin administration & dosage, Carcinoma, Neuroendocrine radiotherapy, Carcinoma, Neuroendocrine surgery, Carcinoma, Small Cell radiotherapy, Carcinoma, Small Cell surgery, Carcinoma, Squamous Cell radiotherapy, Carcinoma, Squamous Cell surgery, Cisplatin administration & dosage, Combined Modality Therapy methods, Etoposide administration & dosage, Female, Head and Neck Neoplasms radiotherapy, Head and Neck Neoplasms surgery, Humans, Male, Middle Aged, Retrospective Studies, Squamous Cell Carcinoma of Head and Neck, Treatment Outcome, Antineoplastic Combined Chemotherapy Protocols therapeutic use, Carcinoma, Neuroendocrine drug therapy, Carcinoma, Small Cell drug therapy, Carcinoma, Squamous Cell drug therapy, Head and Neck Neoplasms drug therapy
- Abstract
Poorly differentiated head and neck neuroendocrine neoplasms are very rare. Surgical resection alone is insufficient to control the disease because of the high incidence of metastases. However, due to the lack of randomised clinical trials, treatment recommendations for this cancer vary considerably and are based on a limited number of small retrospective studies. We performed a retrospective analysis of all patients treated at our institution between 2003 and 2011. We assessed the stage of disease, type of therapy, toxicity, treatment response, time to progression and overall survival for all cases. Ten patients received combined modality treatment with chemotherapy in addition to surgery or radiation or both. According to Response Evaluation Criteria In Solid Tumours (RECIST) criteria, six of nine evaluable patients achieved complete remission and three patients had a partial remission. The mean duration of response was 358 days, with a range from 141 to 1080 days. The overall 1-year survival rate was 88%; however, only approximately 50% of patients were alive after 2 years. Multimodality treatment concepts induce high initial remission rates in poorly differentiated neuroendocrine head and neck carcinomas. However, the time to relapse is usually short, and therefore long-term prognosis of this rare head and neck tumour remains poor., (© 2013 John Wiley & Sons Ltd.)
- Published
- 2013
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43. [Complete remission of multiple brain metastases of non-small cell lung cancer induced by gefitinib monotherapy].
- Author
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Müller F, Riesenberg H, Hirnle P, Gehl HB, Düwel P, and Görner M
- Subjects
- Adenocarcinoma pathology, Adenocarcinoma radiotherapy, Adult, Brain Neoplasms pathology, Brain Neoplasms radiotherapy, Cranial Irradiation, Drug Resistance, Neoplasm, Female, Gefitinib, Humans, Liver Neoplasms drug therapy, Liver Neoplasms pathology, Liver Neoplasms secondary, Lung Neoplasms pathology, Lung Neoplasms radiotherapy, Lymphatic Metastasis pathology, Lymphatic Metastasis radiotherapy, Magnetic Resonance Imaging, Neoplasm Staging, Radiotherapy Dosage, Radiotherapy Planning, Computer-Assisted, Adenocarcinoma secondary, Antineoplastic Agents therapeutic use, Brain Neoplasms secondary, Lung Neoplasms drug therapy, Quinazolines therapeutic use
- Abstract
Background: While the activity of tyrosine kinase inhibitors as the first line treatment for primary tumors in patients with stage IV non-small cell lung cancer and a positive EGF receptor mutation is well known, little data on the efficacy in controlling cerebral metastases are available., Case Report and Results: A 43-year-old woman was diagnosed with non-small cell lung cancer with cerebral and hepatic metastases. Emergency radiation therapy was initiated at the time of diagnosis due to superior vena cava syndrome. However, after she failed to respond to this therapy and in light of a positive EGF receptor mutation, gefitinib was added at a dose of 250 mg/day while continuing radiation to the primary lesion and cervical lymph nodes. She showed a rapid clinical and radiologic response with complete remission of the cerebral metastases 6 weeks after starting gefitinib. No severe toxicity was observed., Conclusion: This case demonstrates that gefitinib can be given during radiation treatment without significant toxicity. Furthermore, complete remission of cerebral metastases can be achieved with tyrosine kinase inhibitor monotherapy.
- Published
- 2011
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44. Petrous apex cholesterol granuloma involving the sphenoid sinus.
- Author
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Korbmacher D, Lehmann M, Gehl HB, Ebmeyer J, and Sudhoff H
- Subjects
- Adult, Granuloma, Foreign-Body surgery, Humans, Male, Petrous Bone surgery, Sphenoid Sinus surgery, Cholesterol, Granuloma, Foreign-Body diagnosis, Magnetic Resonance Imaging
- Abstract
Petrous apex cholesterol granulomas are slowly expanding lesions that clinically present with a variety of cranial nerve deficits. We present a case of a 40-year-old man with a right-sided, sudden-onset hearing loss. Apart from a 60-dB high-frequency sensorineural hearing loss in the right ear, all other neurotologic examinations were normal. Computed tomography revealed partial destruction of the right carotid canal, petrous apex, and clivus. Surgical treatment was performed via an endoscopic transnasal, trans-sphenoid approach using an image-guidance system. Postoperative magnetic resonance imaging showed a significant reduction in the size of the cholesterol granuloma and a stable hearing threshold.
- Published
- 2011
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45. [Significance of abdominal wall CT-angiography in planning DIEA perforator flaps, TRAM flaps and SIEA flaps].
- Author
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Fansa H, Schirmer S, Frerichs O, and Gehl HB
- Subjects
- Epigastric Arteries diagnostic imaging, Epigastric Arteries surgery, Female, Humans, Microvessels diagnostic imaging, Retrospective Studies, Sensitivity and Specificity, Angiography, Mammaplasty methods, Microsurgery methods, Surgical Flaps blood supply, Tissue and Organ Harvesting methods, Tomography, X-Ray Computed
- Abstract
Muscle sparing TRAM flaps and DIEA perforator flaps are standard procedures for breast reconstruction. Recently CT-angiography has been established to evaluate perforator vessels pre-operatively. CT-angiography was introduced to our department in July 2009. In a retrospective analysis data of the last 20 patients (altogether 22 flaps) before CT-angiography introduction and the following 20 (also 22 flaps) patients after introduction of CT-angiography were analysed with regard to the ratio of TRAM to DIEP flaps, and the time required to raise the flaps. The same surgeon raised all flaps. As different surgeons performed dissection of the recipient site, anastomoses, and insertion of flaps, and patients received primary (with sentinel or complete lymphadenctomy) or secondary reconstructions, only the time required harvesting the flap was compared. Thus other influences on raising the flap were eliminated. DIEP flaps were harvested with one single perforator. If perfusion or was considered not to be safe via one single perforator a muscle sparing TRAM flap (ms2) was raised. Angiography was performed using a 64-slice multi-detector CT scanner. CT-angiography did not lead to an increased rate of DIEP flaps in relation to ms2-TRAM flaps. Harvesting time of all flap types with CT-angiography on average was 121 min, without CT-angiography 135 min. This was not significantly different. However, separate analysis of DIEP flaps and ms2-TRAM flaps revealed a significant advantage of CT-angiography based harvesting of DIEP flaps of 26 min: with CT-angiography 101 min vs. 127 min without CT-angiography (p<0.028). There were no significant differences for ms2-TRAM flaps. All scans showed course and branching, diameter and size of the inferior epigastric artery. If evident the superficial inferior epigastric artery (SIEA) was marked. Dosage was 292 mGy-606 mGy×cm dependent on body weight. CTDI was 6.8-14.7 mGy. CT-angiography is a reproducible and observer independent procedure that reliably demonstrates the inferior epigastric artery and its perforating branches. Sensitivity is considered to be 99,6%. Additionally the superficial inferior epigastric artery can be evaluated. In our patients the ratio of ms2-TRAM flaps to DIEP flaps was not affected by introducing CT-angiography. However, DIEP flap harvesting was significantly accelerated. Harvesting of ms2-TRAM flaps was not affected. It remains to be seen whether the observed time advantage is really essential for this operation. Preoperative imaging of the perforators allows establishing a detailed, observable and comprehensible operation strategy, which particularly facilitates surgical training and learning of perforator dissection., (© Georg Thieme Verlag KG Stuttgart · New York.)
- Published
- 2011
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46. Multicenter, double-blind, randomized, intraindividual crossover comparison of gadobenate dimeglumine and gadopentetate dimeglumine for Breast MR imaging (DETECT Trial).
- Author
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Martincich L, Faivre-Pierret M, Zechmann CM, Corcione S, van den Bosch HC, Peng WJ, Petrillo A, Siegmann KC, Heverhagen JT, Panizza P, Gehl HB, Diekmann F, Pediconi F, Ma L, Gilbert FJ, Sardanelli F, Belli P, Salvatore M, Kreitner KF, Weiss CM, and Zuiani C
- Subjects
- Adult, Aged, Aged, 80 and over, Breast Neoplasms pathology, Chi-Square Distribution, China, Cross-Over Studies, Double-Blind Method, Europe, Female, Humans, Image Interpretation, Computer-Assisted, Middle Aged, Predictive Value of Tests, Prospective Studies, Sensitivity and Specificity, Breast Neoplasms diagnosis, Contrast Media, Gadolinium DTPA, Magnetic Resonance Imaging methods, Meglumine analogs & derivatives, Organometallic Compounds
- Abstract
Purpose: To intraindividually compare 0.1 mmol/kg doses of gadobenate dimeglumine and gadopentetate dimeglumine for contrast material-enhanced breast magnetic resonance (MR) imaging by using a prospective, multicenter double-blind, randomized protocol., Materials and Methods: Institutional review board approval and patient informed consent were obtained. One hundred sixty-two women (mean age, 52.8 years ± 12.3 [standard deviation]) enrolled at 17 sites in Europe and China between July 2007 and May 2009 underwent at least one breast MR imaging examination at 1.5 T by using three-dimensional spoiled gradient-echo sequences. Of these, 151 women received both contrast agents in randomized order in otherwise identical examinations separated by more than 2 but less than 7 days. Images, acquired at 2-minute or shorter intervals after contrast agent injection, were evaluated independently by three blinded radiologists unaffiliated with enrollment centers. Histopathologic confirmation was available for all malignant lesions (n = 144), while benign lesions were confirmed either by using histopathologic examination (n = 52) or by at least 12-month diagnostic follow-up (n = 20) with mammography and/or ultrasonography. Determinations of malignant lesion detection rates and diagnostic performance (sensitivity, specificity, accuracy, positive predictive value [PPV], and negative predictive value [NPV]) were performed and compared (McNemar and Wald tests). A full safety assessment was performed., Results: Significant superiority for gadobenate dimeglumine was noted by readers 1, 2, and 3 for malignant lesion detection rate (91.7%, 93.1%, 94.4% vs 79.9%, 80.6%, 83.3%, respectively; P ≤ .0003). Readers 1, 2, and 3 reported significantly superior diagnostic performance (sensitivity, specificity, and accuracy) for breast cancer detection with gadobenate dimeglumine (91.1%, 94.5%, 95.2% vs 81.2%, 82.6%, 84.6%; 99.0%, 98.2%, 96.9% vs 97.8%, 96.9%, 93.8%; 98.2%, 97.8%, 96.7% vs 96.1%, 95.4%, 92.8%, respectively; P ≤ .0094) and significantly superior PPV (91.1%, 85.2%, 77.2% vs 80.7%, 75.5%, 60.9%, respectively; P ≤ .0002) and NPV (99.0%, 99.4%, 99.4% vs 97.8%, 98.0%, 98.1%, respectively; P ≤ .0003). No safety concerns were noted with either agent., Conclusion: Gadobenate dimeglumine is superior to gadopentetate dimeglumine for breast cancer diagnosis. © RSNA, 2010 Clinical trial registration no. NCT00486473 (http://www.clinicaltrials.gov/)., Supplemental Material: http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.10100968/-/DC1.
- Published
- 2011
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47. Schwannoma of the larynx.
- Author
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Ebmeyer J, Reineke U, Gehl HB, Hamberger U, Mlynski R, Essing M, Upile T, and Sudhoff H
- Subjects
- Adult, Female, Humans, Laryngeal Neoplasms diagnosis, Laryngeal Neoplasms surgery, Magnetic Resonance Imaging, Neurilemmoma diagnosis, Neurilemmoma surgery, Tomography, X-Ray Computed, Laryngeal Neoplasms pathology, Neurilemmoma pathology
- Abstract
Objectives: Neurogenic tumors of the larynx are extremely rare. The goal of this report is to advert to this rare disease, to review and discuss diagnostics, differential diagnoses and treatment options., Study Design: Retrospective case report and review of the literature., Methods: Case report of a schwannoma of the supraglottic larynx and review of the English- and German-language literature regarding neurogenic tumors of the larynx., Results: Neurogenic laryngeal tumors typically involve the supraglottic larynx, rarely the glottis. They can course globus sensation, dysphagia, dysphonia and upper airway obstruction. Imaging does not yield a definite diagnosis. The only curative treatment option is complete surgical resection., Conclusions: A definite diagnosis can only be made histologically. Endoscopic (laser-) resection for smaller lesions and external approaches for larger lesions are recommended treatment options.
- Published
- 2009
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48. Abdominal and iliac arterial stenoses: comparative double-blinded randomized study of diagnostic accuracy of 3D MR angiography with gadodiamide or gadopentetate dimeglumine.
- Author
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Schaefer PJ, Boudghene FP, Brambs HJ, Bret-Zurita M, Caniego JL, Coulden RA, Gehl HB, Hammerstingl R, Huber A, Mendez RJ, Nonent M, Oestmann JW, Pueyo JC, Thurnher S, Weishaupt D, and Jahnke T
- Subjects
- Adult, Aged, Aged, 80 and over, Angiography, Digital Subtraction, Arterial Occlusive Diseases diagnostic imaging, Double-Blind Method, Female, Humans, Male, Middle Aged, Predictive Value of Tests, Prospective Studies, Sensitivity and Specificity, Abdomen blood supply, Arterial Occlusive Diseases diagnosis, Contrast Media, Gadolinium DTPA, Iliac Artery, Imaging, Three-Dimensional, Magnetic Resonance Angiography methods
- Abstract
Purpose: To prospectively evaluate accuracy of gadolinium-enhanced three-dimensional (3D) magnetic resonance (MR) angiography with gadodiamide and gadopentetate dimeglumine (0.1 mmol/kg), with intraarterial DSA as reference standard, for imaging abdominal and iliac arterial stenoses., Materials and Methods: The study was approved by all institutional review boards; informed consent was obtained from each subject before procedures. Two hundred forty-seven subjects were included; 240 received either contrast agent and were available for safety analysis; 222 were available for accuracy analysis. Enhanced 3D MR angiography and DSA were performed; image data were evaluated in a double-blinded randomized study. Stenoses were classified as not relevant (<50% stenosis) or relevant (> or =50%). For detection of main stenosis, accuracy with enhanced 3D MR angiography compared with that with DSA was determined., Results: The difference in accuracy for imaging with gadodiamide and gadopentetate was 3.6%. Noninferiority was inferred because the lower bound of the exact two-sided 95% confidence interval was -10.1 and was above the noninferiority margin (-15%). Accuracy for detection of the main stenosis was low, 56.4% for gadodiamide and 52.8% for gadopentetate group. Subgroup analysis with exclusion of inferior mesenteric artery and internal iliac arteries and the most false-positive stenosis classifications yielded better results: 76.6% and 71.6%, respectively. Sensitivity, specificity, and negative and positive predictive values did not differ substantially between study groups. In the main analysis, values were 44%, 96%, 35%, and 97% for gadodiamide and 44%, 83%, 30%, and 90% for gadopentetate, respectively. In the subgroup analysis, values were 66%, 95%, 61%, and 96% for gadodiamide and 63%, 86%, 58%, and 88% for gadopentetate, respectively., Conclusion: Noninferiority of gadodiamide versus gadopentetate was verified based on the primary end point, which was accuracy for detection of the main stenosis with enhanced 3D MR angiography compared with DSA., (Copyright RSNA, 2006.)
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- 2006
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49. Visceral fat deposition and insulin sensitivity in depressed women with and without comorbid borderline personality disorder.
- Author
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Kahl KG, Bester M, Greggersen W, Rudolf S, Dibbelt L, Stoeckelhuber BM, Gehl HB, Sipos V, Hohagen F, and Schweiger U
- Subjects
- Adult, Borderline Personality Disorder blood, Borderline Personality Disorder epidemiology, Borderline Personality Disorder metabolism, Comorbidity, Depressive Disorder, Major blood, Depressive Disorder, Major epidemiology, Depressive Disorder, Major metabolism, Diabetes Mellitus, Type 2 immunology, Diabetes Mellitus, Type 2 metabolism, Female, Glucose metabolism, Homeostasis immunology, Homeostasis physiology, Humans, Hydrocortisone blood, Insulin Resistance immunology, Interleukin-6 blood, Intra-Abdominal Fat immunology, Intra-Abdominal Fat metabolism, Magnetic Resonance Imaging, Models, Biological, Tumor Necrosis Factor-alpha analysis, Borderline Personality Disorder immunology, Depressive Disorder, Major immunology, Insulin Resistance physiology, Intra-Abdominal Fat physiopathology
- Abstract
Objective: Major depressive disorder (MDD) is associated with increased intra-abdominal fat, an important antecedent of noninsulin-dependent diabetes mellitus (NIDDM) and cardiovascular disorders. Furthermore, MDD is commonly accompanied by endocrine and immune dysregulation that has also been discussed in connection with the pathogenesis of NIDDM and ischemic heart disease. In borderline personality disorder (BPD), a dysregulation of the hypothalamic-pituitary-adrenal system has also been described. Therefore, our study aimed at examining visceral fat, insulin resistance, and alterations of cortisol and cytokines in young depressed women with and without comorbid BPD., Methods: Visceral fat was measured in 18 premenopausal women with MDD and in 18 women comorbid with MDD and BPD by means of magnetic resonance tomography at the level of the first lumbar vertebral body. Twelve BPD patients without MDD and 20 healthy women served as the comparison groups. Concentrations of fasting cortisol, tumor necrosis factor-alpha, and interleukin-6 were measured, and indicators of insulin resistance and beta-cell sensitivity were calculated according to the homeostasis assessment model., Results: We found increased visceral fat in women comorbid with MDD and BPD, and to a lesser extent, in women with MDD but without BPD. Insulin sensitivity was reduced in comorbid patients. Serum interleukin-6 (IL-6) and tumor necrosis factor-alpha concentrations were significantly increased in both groups of depressed patients. Reduced insulin sensitivity correlated with the amount of visceral fat and with serum concentrations of IL-6., Conclusion: Young depressed women with and without comorbid BPD display increased visceral fat and may constitute a risk group for the development of NIDDM and the metabolic syndrome. Our data support the hypothesis that the immune and endocrine alterations associated with MDD and BPD may contribute to the pathophysiologic processes associated with NIDDM.
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- 2005
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50. Decreased osteoprotegerin and increased bone turnover in young female patients with major depressive disorder and a lifetime history of anorexia nervosa.
- Author
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Kahl KG, Rudolf S, Dibbelt L, Stoeckelhuber BM, Gehl HB, Hohagen F, and Schweiger U
- Subjects
- Adolescent, Adult, Anorexia Nervosa blood, Anorexia Nervosa physiopathology, Bone Density, Bone Diseases, Metabolic blood, Bone Diseases, Metabolic physiopathology, Cytokines blood, Depressive Disorder, Major blood, Depressive Disorder, Major physiopathology, Female, Hormones blood, Humans, Lumbar Vertebrae physiopathology, Osteoprotegerin, Tumor Necrosis Factor-alpha analysis, Anorexia Nervosa complications, Bone Diseases, Metabolic etiology, Depressive Disorder, Major complications, Glycoproteins blood, Receptors, Cytoplasmic and Nuclear blood, Receptors, Tumor Necrosis Factor blood
- Abstract
Low bone mineral density (BMD) is a frequent, often persistent complication in patients with major depressive disorder (MDD) and anorexia nervosa (AN) that increases the risk of pathologic fractures. The pathogenetic process underlying osteopenia in MDD and AN is still unclear, although several factors, including a dysbalance of cytokines, are associated with loss of bone mass. Alterations in the serum levels of cytokines have been observed in patients with MDD, AN, and other psychiatric disorders. Therefore, we examined serum levels of cytokines, markers of bone turnover, and BMD in 13 patients with MDD and a lifetime history of AN. Bone turnover markers (osteocalcin and C-terminal degradation products of type I collagen) and tumor necrosis factor alpha (TNF-alpha) in patients were significantly increased compared with those of the control group. Osteoprotegerin (OPG) in patients was significantly decreased. Eight of 13 patients (62%) displayed osteopenia at the lumbar spine. TNF-alpha correlated significantly with C-terminal degradation products of type I collagen, an osteoclastic marker, but significantly negatively with OPG. Our data suggest that TNF-alpha and OPG may play a role in the pathogenetic process underlying osteopenia in these patients.
- Published
- 2005
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