88 results on '"Lell M"'
Search Results
2. Impact of whole body electromyostimulation on cardiometabolic risk factors in older women with sarcopenic obesity: the randomized controlled FORMOsA-sarcopenic obesity study
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Wittmann K, Sieber C, von Stengel S, Kohl M, Freiberger E, Jakob F, Lell M, Engelke K, and Kemmler W
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Sarcopenic Obesity ,Whole-Body Electromyostimulation ,Cardiometabolic Risk ,Metabolic Syndrome ,Community-Dwelling ,Older Woman ,Geriatrics ,RC952-954.6 - Abstract
Katharina Wittmann,1 Cornel Sieber,2 Simon von Stengel,1 Matthias Kohl,3 Ellen Freiberger,2 Franz Jakob,4 Michael Lell,5 Klaus Engelke,1 Wolfgang Kemmler1 1Institute of Medical Physics, Faculty of Medicine, Friedrich-Alexander University of Erlangen-Nürnberg, 2Institute for Biomedicine of Aging, Faculty of Medicine, Friedrich-Alexander University of Erlangen-Nürnberg, Erlangen, 3Faculty of Medical and Life Sciences, University of Furtwangen, 4Musculoskeletal Research Center, University of Würzburg, Würzburg, 5Department of Radiology and Nuclear Medicine, Klinikum Nürnberg, Paracelsus Medizinische Privatuniversität, Nürnberg, Germany Background: Sarcopenic obesity (SO) is characterized by a combination of low muscle and high fat mass with an additive negative effect of both conditions on cardiometabolic risk. The aim of the study was to determine the effect of whole-body electromyostimulation (WB-EMS) on the metabolic syndrome (MetS) in community-dwelling women aged ≥70 years with SO. Methods: The study was conducted in an ambulatory university setting. Seventy-five community-dwelling women aged ≥70 years with SO living in Northern Bavaria, Germany, were randomly allocated to either 6 months of WB-EMS application with (WB-EMS&P) or without (WB-EMS) dietary supplementation (150 kcal/day, 56% protein) or a non-training control group (CG). WB-EMS included one session of 20 min (85 Hz, 350 µs, 4 s of strain–4 s of rest) per week with moderate-to-high intensity. The primary study endpoint was the MetS Z-score with the components waist circumference (WC), mean arterial pressure (MAP), triglycerides, fasting plasma glucose, and high-density lipoprotein cholesterol (HDL-C); secondary study endpoints were changes in these determining variables. Results: MetS Z-score decreased in both groups; however, changes compared with the CG were significant (P=0.001) in the WB-EMS&P group only. On analyzing the components of the MetS, significant positive effects for both WB-EMS groups (P≤0.038) were identified for MAP, while the WB-EMS group significantly differed for WC (P=0.036), and the WB-EMS&P group significantly differed for HDL-C (P=0.006) from the CG. No significant differences were observed between the WB-EMS groups. Conclusion: The study clearly confirms the favorable effect of WB-EMS application on the MetS in community-dwelling women aged ≥70 years with SO. However, protein-enriched supplements did not increase effects of WB-EMS alone. In summary, we considered this novel technology an effective and safe method to prevent cardiometabolic risk factors and diseases in older women unable or unwilling to exercise conventionally. Keywords: sarcopenia, obesity, whole-body electromyostimulation, cardiovascular, metabolic risk, metabolic syndrome, community-dwelling, older people
- Published
- 2016
3. Sportwissenschaft
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Kemmler W, Tutor M, Lell M, Scharf M, Fraunberger L, and von Stengel S
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Sports medicine ,RC1200-1245 - Published
- 2014
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4. Transvenous Renal Transplant Biopsy via a Transfemoral Approach
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Schmid, A., Jacobi, J., Kuefner, M.A., Lell, M., Wuest, W., Mayer-Kadner, I., Benz, K., Schmid, M., Amann, K., and Uder, M.
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- 2013
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5. Glymphatic System in Ocular Diseases: Evaluation of MRI Findings.
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Manava, P., Eckrich, C., Luciani, F., Schmidbauer, J., Lell, M. M., and Detmar, K.
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- 2022
- Full Text
- View/download PDF
6. Carotid Artery Calcium: Accuracy of a Calcium Score by Computed Tomography—An In vitro Study with Comparison to Sonography and Histology
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Denzel, C, Lell, M, Maak, M, Höckl, M, Balzer, K, Müller, K.-M, Fellner, C, Fellner, F.A, and Lang, W
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- 2004
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7. Testing of alignment parameters for ancient samples: evaluating and optimizing mapping parameters for ancient samples using the TAPAS tool
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Taron, U, Lell, M, Barlow, A, and Paijmans, J
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lcsh:Genetics ,paleogenomics ,lcsh:QH426-470 ,palaeogenomics ,short-read mapping ,ancient DNA ,alignment sensitivity/specificity - Abstract
High-throughput sequence data retrieved from ancient or other degraded samples has led to unprecedented insights into the evolutionary history of many species, but the analysis of such sequences also poses specific computational challenges. The most commonly used approach involves mapping sequence reads to a reference genome. However, this process becomes increasingly challenging with an elevated genetic distance between target and reference or with the presence of contaminant sequences with high sequence similarity to the target species. The evaluation and testing of mapping efficiency and stringency are thus paramount for the reliable identification and analysis of ancient sequences. In this paper, we present ‘TAPAS’, (Testing of Alignment Parameters for Ancient Samples), a computational tool that enables the systematic testing of mapping tools for ancient data by simulating sequence data reflecting the properties of an ancient dataset and performing test runs using the mapping software and parameter settings of interest. We showcase TAPAS by using it to assess and improve mapping strategy for a degraded sample from a banded linsang (Prionodon linsang), for which no closely related reference is currently available. This enables a 1.8-fold increase of the number of mapped reads without sacrificing mapping specificity. The increase of mapped reads effectively reduces the need for additional sequencing, thus making more economical use of time, resources, and sample material.
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- 2018
8. Die Computertomographie bei der Bildgebung von Kindern mit kongenitalen Herzvitien
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Glaser-Gallion, N., Stinn, B., Alkadhi, H., Lell, M., Goo, H.W., Paul, J. -F, Wildermuth, S., Leschka, S., Glaser-Gallion, N., Stinn, B., Alkadhi, H., Lell, M., Goo, H.W., Paul, J. -F, Wildermuth, S., and Leschka, S.
- Abstract
Zusammenfassung: Kongenitale Herzfehler sind die häufigsten kongenitalen Fehlbildungen. Echokardiographie und Katheterangiographie gelten allgemein als Goldstandard zur Abklärung angeborener Herzerkrankungen. Die Magnetresonanztomographie ist aufgrund ihrer Fähigkeit, Herzvitien morphologisch und funktionell zu charakterisieren, als ein wichtiges ergänzendes Verfahren anzusehen. Durch mehr und mehr dosissparende Untersuchungsprotokolle der neuesten Gerätegenerationen und eine gleichzeitig bessere zeitliche und räumliche Auflösung findet die Computertomographie zunehmend Eingang in die Abklärung kongenitaler Herzfehler. In der präoperativen Planung und der postoperativen Kontrolle erlaubt sie eine übersichtliche Darstellung komplexer Fehlbildung nicht nur des Herzens, sondern auch der pulmonalvenösen und -arteriellen Zirkulation sowie des systemischen Kreislaufs. Dieser Beitrag gibt eine Übersicht über die technischen Aspekte der kardialen CT und die Anpassung des Untersuchungsprotokolls an die zu erwartende Pathologie und das Alter des Kindes. Zudem werden die Möglichkeiten und Limitationen der unterschiedlichen dosissparenden Protokolle erläutert
- Published
- 2018
9. Diagnostics and therapy of vestibular schwannomas - an interdisciplinary challenge
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Rosahl, S, Bohr, C, Lell, M, Hamm, K, Iro, H, Rosahl, S, Bohr, C, Lell, M, Hamm, K, and Iro, H
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Vestibular schwannomas (VS) expand slowly in the internal auditory canal, in the cerebellopontine angle, inside the cochlear and the labyrinth. Larger tumors can displace and compress the brainstem. With an annual incidence of 1:100,000 vestibular schwannoma represent 6-7% of all intracranial tumors. In the cerebellopontine angle they are by far the most neoplasm with 90% of all lesions located in this region. Magnetic resonance imaging (MRI), audiometry, and vestibular diagnostics are the mainstays of the clinical workup for patients harboring tumors. The first part of this paper delivers an overview of tumor stages, the most common grading scales for facial nerve function and hearing as well as a short introduction to the examination of vestibular function. Upholding or improving quality of life is the central concern in counseling and treating a patient with vestibular schwannoma. Preservation of neuronal function is essential and the management options - watchful waiting, microsurgery and stereotactic radiation - should be custom-tailored to the individual situation of the patient. Continuing interdisciplinary exchange is important to monitor treatment quality and to improve treatment results. Recently, several articles and reviews have been published on the topic of vestibular schwannoma. On the occasion of the 88th annual meeting of the German Society of Oto-Rhino-Laryngology, Head and Neck surgery a special volume of the journal "HNO" will be printed. Hence this presentation has been designed to deviate from the traditional standard which commonly consists of a pure literature review. The current paper was conceptually woven around a series of interdisciplinary cases that outline examples for every stage of the disease that show characteristic results for management options to date. Systematic clinical decision pathways have been deduced from our experience and from results reported in the literature. These pathways are graphically outlined after the case pre
- Published
- 2017
10. Verlaufsbeobachtung von Gichttophi mittels Dual Energy CT bei Patienten mit chronischer Gicht unter harnsäuresenkender Medikation
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Ellmann, H, Bayat, S, d'Oliveira, I, Englbrecht, M, Araujo, E, Mendonca, S, Cavallaro, A, Lell, M, Manger, B, Schett, G, and Rech, J
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Gichttophi ,Febuxostat ,ddc: 610 ,Dual Energy CT ,Allopurinol ,Pegloticase ,610 Medical sciences ,Medicine - Abstract
Einleitung: Mittels Dual Energy CT lassen sich Gichtkristallablagerungen hinsichtlich Größe und Quantität verlässlich bestimmen. Longitudinale Verlaufsbeobachtungen sind derzeit, bis auf eine kleine Studie unter Pegloticase, nicht vorhanden. In unserer Untersuchung geht es um [zum vollständigen Text gelangen Sie über die oben angegebene URL], 44. Kongress der Deutschen Gesellschaft für Rheumatologie (DGRh); 30. Jahrestagung der Deutschen Gesellschaft für Orthopädische Rheumatologie (DGORh); 26. Jahrestagung der Gesellschaft für Kinder- und Jugendrheumatologie (GKJR)
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- 2016
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11. Microcystic adnexal carcinoma (MAC)-like squamous cell carcinoma as a differential diagnosis to Bell´s palsy: review of guidelines for refractory facial nerve palsy
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Mueller, S. K., primary, Iro, H., additional, Lell, M., additional, Seifert, F., additional, Bohr, C., additional, Scherl, C., additional, Agaimy, A., additional, and Traxdorf, M., additional
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- 2017
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12. Die diagnostische Aussagekraft der Felsenbein-MRT-Bildgebung bei der Erkennung von Residual- oder Rezidivcholesteatomen als Alternative zur Second look Operation
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Pohmer, S, Lell, M, Brase, C, Iro, H, and Hornung, J
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ddc: 610 ,610 Medical sciences ,Medicine - Abstract
Einleitung: An unserer Klinik ist nach Cholesteatomentfernung über einen endauralen Zugang mit Gehörgangsrekonstruktion die Durchführung einer Second-Look-Operation das übliche therapeutische Vorgehen. Diese Studie versucht den diagnostischen Nutzen einer MRT-Bildgebung des Felsenbeins[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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13. Improved Image Quality in Head and Neck CT Using a 3D Iterative Approach to Reduce Metal Artifact
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Wuest, W., primary, May, M.S., additional, Brand, M., additional, Bayerl, N., additional, Krauss, A., additional, Uder, M., additional, and Lell, M., additional
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- 2015
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14. Tophus resolution with pegloticase: a prospective dual-energy CT study
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Araujo, E. G., primary, Bayat, S., additional, Petsch, C., additional, Englbrecht, M., additional, Faustini, F., additional, Kleyer, A., additional, Hueber, A. J., additional, Cavallaro, A., additional, Lell, M., additional, Dalbeth, N., additional, Manger, B., additional, Schett, G., additional, and Rech, J., additional
- Published
- 2015
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15. Imaging the Parasinus Region with a Third-Generation Dual-Source CT and the Effect of Tin Filtration on Image Quality and Radiation Dose
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Lell, M. M., primary, May, M. S., additional, Brand, M., additional, Eller, A., additional, Buder, T., additional, Hofmann, E., additional, Uder, M., additional, and Wuest, W., additional
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- 2015
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16. Vascular Mapping of Head and Neck: Computed Tomography Angiography Versus Digital Subtraction Angiography
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Kramer, M. Vairaktaris, E. Nkenke, E. Schlegel, K.A. Neukam, F.W. Lell, M.
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Purpose: The aim of the study was to compare multislice computed tomography angiography (MSCTA) to digital subtraction angiography (DSA) for vascular mapping of the head and neck. Patients and Methods: In 50 patients who were scheduled for microvascular reconstruction of the mandible with osteomyocutaneous flaps, MSCTA was carried out before surgery. DSA served as the method of reference. Selective common carotid angiograms were acquired in 2 projections for both sides of the neck. A 64-slice spiral computed tomography (CT) was carried out with a dual-phase protocol, using the arterial phase images for 3-dimensional CTA reconstruction. Volume rendering was used to visualize MSCTA data. Results: No adverse reactions or complications occurred during or after the procedures. All CT angiograms were of diagnostic quality. No statistically significant differences between MSCTA and DSA were found for the detection of branches of the external carotid artery that are relevant host vessels for microsurgery neither in the group of 26 patients who had not had surgical treatment before (P = .687), nor in the group of 24 patients who were affected by either a tumor recurrence or an infected osteoradionecrosis (P = .508). Conclusion: MSCTA proved to be a reliable alternative to DSA in vascular mapping for planning of microvascular reconstruction of the mandible. © 2008 American Association of Oral and Maxillofacial Surgeons.
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- 2008
17. Primary Intraosseous Meningioma of the Mandible: CT and MR Imaging Features
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Lell, M., Tudor, C., Aigner, T., and Kessler, P.
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Adult ,Mandible ,Osteolysis ,Magnetic Resonance Imaging ,nervous system diseases ,Diagnosis, Differential ,stomatognathic diseases ,Mandibular Neoplasms ,stomatognathic system ,Tooth Apex ,Radiography, Panoramic ,otorhinolaryngologic diseases ,Image Processing, Computer-Assisted ,Meningeal Neoplasms ,Humans ,Female ,Meningioma ,Tomography, X-Ray Computed ,neoplasms ,Head & Neck - Abstract
SUMMARY: We describe the rare entity of an intraosseous meningioma arising in the mandible. The meningioma was found incidentally in an asymptomatic adult patient on dental radiography, mimicking other cystic-appearing jaw masses. The CT and MR imaging features of mandibular meningioma are reviewed with reference to prior published descriptions of this unusual entity.
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- 2007
18. Solitary fibrous tumor in the tongue. Case report and review of the literature [Solitärer fibröser tumor der zunge. Fallbericht und literaturübersicht]
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Nkenke, E. Fenner, M. Lell, M. Vairaktaris, E. Neukam, F.W. Faller, G.
- Abstract
Solitary fibrous tumors (SFT) are rare, mostly fibroblastic tumors usually situated in the pleura. Extrapleural manifestations have been described. However, the oral cavity is an uncommon localisation of this tumor. We report the very unusual case of an SFT affecting the tongue that could be removed completely because of its clear delineation. Intraoperative incisional biopsies were used to exclude malignancy. For definitive classification of the tumor, additional histopathologic examinations had to be carried out. Because SFT exhibit malignant behavior only in exceptional cases and their recurrence after complete removal has never been encountered, surgery can focus on the preservation of undisturbed function of the tongue. © 2006 Springer Medizin Verlag.
- Published
- 2007
19. Bone-Subtraction CT Angiography for the Evaluation of Intracranial Aneurysms
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Bf, Tomandl, Ernst-Thilo Hammen, Klotz E, Ditt H, Stemper B, and Lell M
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Skull ,Brain ,Angiography, Digital Subtraction ,Contrast Media ,Intracranial Aneurysm ,Cerebral Angiography ,Ophthalmic Artery ,Imaging, Three-Dimensional ,Image Processing, Computer-Assisted ,Humans ,cardiovascular diseases ,Tomography, X-Ray Computed ,Tomography, Spiral Computed ,Carotid Artery, Internal - Abstract
PURPOSE: CT angiography (CTA) has been established for detection and therapy planning of intracranial aneurysms. The analysis of aneurysms at the level of the skull base, however, remains difficult because bone prevents a free view. We report initial clinical results of an approach for automatic bone elimination from CTA data. MATERIAL AND METHODS: Before the bone-removal process 2 datasets are acquired: nonenhanced spiral CT with reduced dose and contrast-enhanced CTA. The software automatically registers the nonenhanced data onto the CTA data and selectively removes bone. Vascular structures, as well as brain tissue, remain visible. In this study, we investigated 27 patients with 29 aneurysms, 13 of which were located at the skull base. 3D volume-rendered images with and without bone removal were reviewed and compared with digital subtraction angiography by 2 radiologists in consensus. RESULTS: All supraclinoidal aneurysms were detected on 3D volume-rendered images of both CTA and bone-subtraction CT angiography (BSCTA). Four intracavernous and 3 paraclinoid aneurysms of the internal carotid artery were not visible or were only partially visible on conventional 3D CTA, whereas they could be optimally visualized with BSCTA. Bone removal was successful in all patients; the average additional time for postprocessing was 6.2 minutes. In 7 patients (26%), perfect bone removal without any artifacts was achieved. In most patients, some bone remnants were still present, though it did not disturb the 3D visualization of vascular structures. CONCLUSION: BSCTA allows robust and fast selective elimination of bony structures, thus ascertaining a better analysis of arteries at the level of the skull base. This is useful for both detection and therapy planning of intracranial aneurysms.
- Published
- 2006
20. Accuracy of prospectively ECG-triggered very low-dose coronary dual-source CT angiography using iterative reconstruction for the detection of coronary artery stenosis: comparison with invasive catheterization
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Layritz, C., primary, Schmid, J., additional, Achenbach, S., additional, Ulzheimer, S., additional, Wuest, W., additional, May, M., additional, Ropers, D., additional, Klinghammer, L., additional, Daniel, W. G., additional, Pflederer, T., additional, and Lell, M., additional
- Published
- 2014
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21. Die Computertomographie bei der Bildgebung von Kindern mit kongenitalen Herzvitien
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Glaser-Gallion, N, Stinn, B, Alkadhi, H, Lell, M, Goo, H W, Paul, J F, Wildermuth, S, Leschka, S, Glaser-Gallion, N, Stinn, B, Alkadhi, H, Lell, M, Goo, H W, Paul, J F, Wildermuth, S, and Leschka, S
- Abstract
Congenital heart diseases are the most common congenital abnormalities of development. In general, echocardiography and cardiac catheter angiography are considered the gold standard for the evaluation of congenital heart disease. Cardiac magnetic resonance imaging has become an important supplementary imaging modality because of its ability to provide an accurate morphological and functional evaluation. The role of cardiac computed tomography in the imaging of patients with congenital heart disease is becoming increasingly more important due to the development of low radiation dose protocols and improvements in the spatial and temporal resolution. In the preoperative depiction and follow-up after surgical repair of congenital heart diseases, cardiac computed tomography provides detailed information of the heart, the venous and arterial pulmonary circulation as well as systemic arteries. This article reviews the technical aspects of cardiac CT and the modification of examination protocols according to the expected pathology and patient age. The potentials and limitations of the various radiation dose reduction strategies are outlined.
- Published
- 2011
22. Carotid CTA: Radiation Exposure and Image Quality with the Use of Attenuation-Based, Automated Kilovolt Selection
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Eller, A., primary, Wuest, W., additional, Kramer, M., additional, May, M., additional, Schmid, A., additional, Uder, M., additional, and Lell, M. M., additional
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- 2013
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23. Comparison of 128-Section Single-Shot Technique with Conventional Spiral Multisection CT for Imaging of the Temporal Bone
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Schwab, S.A., primary, Eberle, S., additional, Adamietz, B., additional, Kuefner, M.A., additional, Kramer, M., additional, Uder, M., additional, and Lell, M., additional
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- 2011
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24. Three-dimensional volume tomographic study of the imaging accuracy of impacted teeth: MSCT and CBCT comparison--an in vitro study
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Hofmann, E., primary, Medelnik, J., additional, Fink, M., additional, Lell, M., additional, and Hirschfelder, U., additional
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- 2011
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25. Coronary computed tomography angiography with a consistent dose below 1 mSv using prospectively electrocardiogram-triggered high-pitch spiral acquisition
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Achenbach, S., primary, Marwan, M., additional, Ropers, D., additional, Schepis, T., additional, Pflederer, T., additional, Anders, K., additional, Kuettner, A., additional, Daniel, W. G., additional, Uder, M., additional, and Lell, M. M., additional
- Published
- 2009
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26. Einfluss hoher vs. niedriger Reizintensität auf die Ausdauerleistungsfähigkeit untrainierter Männer - die RUSH-Studie.
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Kemmler, W., Tutor, M., Lell, M., Scharf, M., Fraunberger, L., and von Stengel, S.
- Abstract
Copyright of German Journal of Sports Medicine / Deutsche Zeitschrift fur Sportmedizin is the property of Verein zur Forderung der Sportmedizin Hannover e.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
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- 2014
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27. Sporadic endolymphatic sac tumor - a diagnostic and therapeutic challenge
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Künzel, J., Agaimy, A., Hornung, J., Lell, M., Ganslandt, O., Semrau, S., and Johannes Zenk
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Adult ,Male ,Time Factors ,Biopsy ,Temporal Bone ,Case Report ,Immunohistochemistry ,Magnetic Resonance Imaging ,Neurosurgical Procedures ,Treatment Outcome ,Medizinische Fakultät ,Biomarkers, Tumor ,Humans ,Neoplasm Invasiveness ,Radiotherapy, Adjuvant ,ddc:610 ,Cranial Irradiation ,Endolymphatic Sac ,Ear Neoplasms - Abstract
Endolymphatic sac tumor (ELST) is a rare low-grade locally aggressive neoplasm of the inner ear that may occur sporadically or in the setting of von Hippel-Lindau syndrome. We herein present a case of sporadic ELST in a 39-year-old man, treated using an interdisciplinary approach (surgery + radiotherapy), with a 10-year follow-up. The patient presented with hearing loss of sudden onset. The treatment of choice for ELST is radical tumor resection, which is associated with a good long-term prognosis. Remission may last for years, but there may be local recurrences, probably as a result of incomplete resection. Adjuvant radiotherapy is an option in case of recurrence and could be discussed after incomplete resection. The purpose of this report is to call attention to ELSTs, which are difficult to diagnose due to their rarity and variety of presentations.
28. Die Computertomographie bei der Bildgebung von Kindern mit kongenitalen Herzvitien
- Author
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Glaser-Gallion, N., Stinn, B., Alkadhi, H., Lell, M., Goo, H.W., Paul, J. -F, Wildermuth, S., Leschka, S., Glaser-Gallion, N., Stinn, B., Alkadhi, H., Lell, M., Goo, H.W., Paul, J. -F, Wildermuth, S., and Leschka, S.
- Abstract
Zusammenfassung: Kongenitale Herzfehler sind die häufigsten kongenitalen Fehlbildungen. Echokardiographie und Katheterangiographie gelten allgemein als Goldstandard zur Abklärung angeborener Herzerkrankungen. Die Magnetresonanztomographie ist aufgrund ihrer Fähigkeit, Herzvitien morphologisch und funktionell zu charakterisieren, als ein wichtiges ergänzendes Verfahren anzusehen. Durch mehr und mehr dosissparende Untersuchungsprotokolle der neuesten Gerätegenerationen und eine gleichzeitig bessere zeitliche und räumliche Auflösung findet die Computertomographie zunehmend Eingang in die Abklärung kongenitaler Herzfehler. In der präoperativen Planung und der postoperativen Kontrolle erlaubt sie eine übersichtliche Darstellung komplexer Fehlbildung nicht nur des Herzens, sondern auch der pulmonalvenösen und -arteriellen Zirkulation sowie des systemischen Kreislaufs. Dieser Beitrag gibt eine Übersicht über die technischen Aspekte der kardialen CT und die Anpassung des Untersuchungsprotokolls an die zu erwartende Pathologie und das Alter des Kindes. Zudem werden die Möglichkeiten und Limitationen der unterschiedlichen dosissparenden Protokolle erläutert
29. Two-view topogram-based anatomy-guided CT reconstruction for prospective risk minimization.
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Liu C, Klein L, Huang Y, Baader E, Lell M, Kachelrieß M, and Maier A
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- Humans, Image Processing, Computer-Assisted methods, Imaging, Three-Dimensional methods, Radiation Dosage, Phantoms, Imaging, Algorithms, Prospective Studies, Tomography, X-Ray Computed methods
- Abstract
To facilitate a prospective estimation of the effective dose of an CT scan prior to the actual scanning in order to use sophisticated patient risk minimizing methods, a prospective spatial dose estimation and the known anatomical structures are required. To this end, a CT reconstruction method is required to reconstruct CT volumes from as few projections as possible, i.e. by using the topograms, with anatomical structures as correct as possible. In this work, an optimized CT reconstruction model based on a generative adversarial network (GAN) is proposed. The GAN is trained to reconstruct 3D volumes from an anterior-posterior and a lateral CT projection. To enhance anatomical structures, a pre-trained organ segmentation network and the 3D perceptual loss are applied during the training phase, so that the model can then generate both organ-enhanced CT volume and organ segmentation masks. The proposed method can reconstruct CT volumes with PSNR of 26.49, RMSE of 196.17, and SSIM of 0.64, compared to 26.21, 201.55 and 0.63 using the baseline method. In terms of the anatomical structure, the proposed method effectively enhances the organ shapes and boundaries and allows for a straight-forward identification of the relevant anatomical structures. We note that conventional reconstruction metrics fail to indicate the enhancement of anatomical structures. In addition to such metrics, the evaluation is expanded with assessing the organ segmentation performance. The average organ dice of the proposed method is 0.71 compared with 0.63 for the baseline model, indicating the enhancement of anatomical structures., (© 2024. The Author(s).)
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- 2024
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30. Sinogenic Orbital Complications.
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Cohnen M, Klingebiel R, Langner S, Lell M, and Rohde S
- Published
- 2022
- Full Text
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31. Glymphatic System in Ocular Diseases: Evaluation of MRI Findings.
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Manava P, Eckrich C, Luciani F, Schmidbauer J, Lell MM, and Detmar K
- Subjects
- Contrast Media metabolism, Humans, Magnetic Resonance Imaging, Prospective Studies, Vitreous Body diagnostic imaging, Vitreous Body metabolism, Gadolinium metabolism, Glymphatic System
- Abstract
Background and Purpose: There is growing evidence of leakage of gadolinium in an impaired blood-retina barrier. We investigated gadolinium enhancement in different eye compartments and correlated the enhancement with specific ophthalmologic diseases., Materials and Methods: In a prospective clinical study (ClinicalTrials.gov Identifier: NCT05035251), 95 patients (63 with and 32 without ophthalmologic disease) were examined before and after gadolinium administration (20 and 120 minutes) with heavily T2-weighted FLAIR. The cohort was divided according to the location of pathology into anterior and posterior eye compartment groups. Relative signal intensity increase in the anterior eye chamber, vitreous body with retina, optic nerve sheath, and the Meckel cave was analyzed and correlated with the final clinical diagnosis., Results: In patients with a disorder in the anterior eye compartment, significant signal intensity increases were found in the central anterior eye chamber ( P 20 minutes = .000, P 120 minutes = .000), lateral anterior eye chamber ( P 20 minutes = .001, P 120 minutes = .005), and vitreous body with retina ( P 20 minutes = .02) compared with the control group. Patients with pathologies in the posterior eye compartment showed higher signal intensity levels in the central anterior eye compartment ( P 20 minutes = .041) and vitreous body with retina ( P 120 minutes = .006)., Conclusions: Increased gadolinium enhancement was found in the central and lateral anterior eye compartments and the vitreous body with retina in patients with anterior eye compartment disorders 20 and 120 minutes after contrast application, suggesting impairment of the blood-aqueous barrier. In patients with a disorder in the posterior eye compartment, pathologic enhancement indicated disruption of the blood-retinal barrier that allows gadolinium to diffuse into the vitreous body with retina from posterior to anterior, opposite to the known physiologic glymphatic pathway., (© 2022 by American Journal of Neuroradiology.)
- Published
- 2022
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32. Optimizing the setup of multienvironmental hybrid wheat yield trials for boosting the selection capability.
- Author
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Lell M, Reif J, and Zhao Y
- Subjects
- Genomics, Genotype, Phenotype, Selection, Genetic, Triticum genetics
- Abstract
The accuracy of genomic prediction increases with increasing heritability, and thus the challenge of optimizing the design of multienvironment yield trials under a limited budget arises. With this in mind, we aimed to find the best of several options to sparsely distribute a fixed number of plots across different environments to increase the accuracy of hybrid performance prediction. We used a comprehensive published genomic and phenotypic data set of 1,604 winter wheat (Triticum aestivum L.) hybrids and compared several commonly used biometric models for phenotypic data analysis in a resampling study to identify the one that most accurately estimated the hybrid performance in different imbalanced trials. Our results showed that when using information about genotypic relationships, genotypic values were more strongly associated with the reference values than when this information was ignored. In addition, a balanced environmental sampling resulted in an adequate characterization of each environment and increased the accuracy for estimating the hybrid performance. One promising design involved dividing the genotypes into equally sized subgroups that were tested in a subset of environments, with the constraint that the subgroups overlapped with respect to the environments. This scenario appears to be particularly appropriate, as it provided both high accuracies in the estimates of genotypic values and had low variability resulting from the data sample used. Thus, we were able to clearly demonstrate the utility for optimizing the design of multienvironment hybrid wheat yield trials in times of genomic selection., (© 2021 The Authors. The Plant Genome published by Wiley Periodicals LLC on behalf of Crop Science Society of America.)
- Published
- 2021
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33. Corrigendum to "Improving contrast enhancement in pulmonary CTA: The value of breathing maneuvers" [Eur J Radiol Open 7 (2020) 100280].
- Author
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Manava P, Galster M, Schoen M, Ficker J, Lell MM, Adamus R, and Bruch M
- Abstract
[This corrects the article DOI: 10.1016/j.ejro.2020.100280.]., (© 2021 The Author(s).)
- Published
- 2021
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34. Improving Contrast Enhancement in Pulmonary CTA: The value of breathing maneuvers.
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Manava P, Galster M, Schoen M, Ficker J, Lell MM, Adamus R, and Bruch M
- Abstract
Purpose: To investigate contrast dynamics and artifacts associated with different breathing maneuvers during pulmonary computed tomography angiography (pCTA) in a prospective randomized clinical trial., Method: Three different breathing maneuvers (inspiration, expiration, Mueller) were randomly assigned to 146 patients receiving pCTA for suspected pulmonary embolism (PE). Contrast enhancement of central and peripheral arteries and imaging quality of lung parenchyma were compared and analyzed. Results were compared by using the analysis of variances (ANOVA) and Kruskal-Wallis-Test., Results: Mean enhancement in the pulmonary trunk was highest during breath-hold in inspiration (293 HU, range 195-460 HU) compared to Mueller (259 HU, range 136-429 HU, p = 0022) and expiration (267 HU, range 115-376 HU). This was similar for the right pulmonary artery (inspiration 289 HU, range 173-454 HU; Mueller 250 HU, range 119-378 HU; p = 0.007; expiration 257 HU, range 114-366 HU; p = 0.032) and left pulmonary artery (inspiration 280.3 HU, range 170-462 HU; Mueller 245 HU, range 111-371 HU; p = 0.016; expiration 252 HU, range 110-371 HU).Delineation of peripheral arteries was significantly better in inspiration vs Mueller (p = 0.006) and expiration (p = 0.049). Assessment of the lung parenchyma was significantly better in inspiration vs Mueller (p = 0.013) or expiration (p < 0.001)., Conclusions: Resting inspiratory position achieved the highest enhancement levels in central and peripheral pulmonary arteries and best image quality of the pulmonary parenchyma in comparison to other breathing maneuvers. It is necessary to train the maneuver prior to the examination in order to avoid deep inspiration with the risk of suboptimal opacification of the pulmonary arteries., Competing Interests: The authors report no declarations of interest., (© 2020 The Authors.)
- Published
- 2020
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35. Diagnostic value of 3D dynamic contrast-enhanced magnetic resonance imaging in lymph node metastases of head and neck tumors: a correlation study with histology.
- Author
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Treutlein C, Stollberg A, Scherl C, Agaimy A, Ellmann S, Iro H, Lell M, Uder M, and Bäuerle T
- Abstract
Background: Accurate staging of cervical lymph nodes (LN) is pivotal for further clinical management of patients with head and neck cancer. Functional magnetic resonance imaging (MRI) such as three-dimensional (3D) dynamic contrast-enhanced (DCE) acquisition might improve the diagnosis of cervical LN metastases., Purpose: To evaluate the additional diagnostic value of high-resolution 3D T1-weighted DCE in detecting LN metastasis compared to standard morphological imaging criteria in patients with head and neck tumors as correlated to histopathology., Material and Methods: Standard MRI with 3D DCE acquisition at voxel sizes of 1 × 1×1 mm was performed in 15 patients before surgery; 92 LN of the head and neck were histopathologically analyzed. A logistic regression analysis of semi-quantitative DCE parameters, time-intensity curve (TIC) shapes, and morphological criteria was performed to differentiate benign from malignant LN., Results: Standard MRI was sufficient for diagnosis of malignancy in LN with a short-axis diameter ≥ 15 mm (n = 17). For LN metastases with a short-axis diameter <15 mm (n = 12), however, the combination of 3D DCE MRI parameters, TIC shapes, and LN diameter significantly increased the sensitivity and specificity of diagnosing metastases (DCE + TIC shape + LN diameter: 92% and 88% vs. DCE only: 83% and 68% ( P < 0.01) vs. LN diameter only: 83% and 77% ( P = 0.04)., Conclusion: MRI including isotropic high-resolution 3D DCE acquisition combined with morphological criteria allows an accurate assessment of small cervical LN metastases in patients with head and neck cancer. For LN ≥ 15 mm diameter, morphologic imaging may suffice to diagnose metastatic disease to the LN., (© The Foundation Acta Radiologica 2020.)
- Published
- 2020
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36. High Intensity Resistance Exercise Training vs. High Intensity (Endurance) Interval Training to Fight Cardiometabolic Risk Factors in Overweight Men 30-50 Years Old.
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Tuttor M, von Stengel S, Kohl M, Lell M, Scharf M, Uder M, Wittke A, and Kemmler W
- Abstract
Cardiovascular and cardiometabolic diseases are leading causes of death worldwide. Exercise favorably affects this problem, however only few invest (enough) time to favorably influence cardiometabolic risk-factors and cardiac morphology/performance. Time-effective, high-intensity, low-volume exercise protocols might increase people's commitment to exercise. To date, most research has focused on high-intensity interval training (HIIT), the endurance type of HIT, while corresponding HIT-resistance training protocols (HIT-RT) are rarely evaluated. In this study we compared the effect of HIIT vs. HIT-RT, predominately on cardiometabolic and cardiac parameters in untrained, overweight-obese, middle-aged men. Eligible, untrained men aged 30-50 years old in full-time employment were extracted from two joint exercise studies that randomly assigned participants to a HIIT, HIT-RT or corresponding control group. HIIT predominately consisted of interval training 90 s-12 min, (2-4 sessions/week), HIT-RT (2-3 sessions/week) was applied as a single set resistance training to muscular failure. Core intervention length of both protocols was 16 weeks. Main inclusion criteria were overweight-obese status (BMI 25-35 kg/m
2 ) and full employment (occupational working time: ≥38.5 h/week). Primary study-endpoint was the Metabolic Syndrome (MetS) Z-Score, secondary study-endpoints were ventricular stroke volume index (SVI) and myocardial mass index (MMI) as determined by Magnetic Resonance Imaging. The Intention to treat (ITT) principle was applied to analyze the summarized data set. Twenty-seven eligible men of the HIT-RT and 30 men of the HIIT group were included in the ITT. Both interventions significantly ( p < 0.001) improve the MetS Z-Score, however the effect of HIIT was superior ( p = 0.049). In parallel, HIT-RT and HIIT significantly affect SVI and MMI, with the effect of HIIT being much more pronounced ( p < 0.001). Although HIIT endurance exercise was superior in favorably affecting cardiometabolic risk and particularly cardiac performance, both exercise methods positively affect cardiometabolic risk factors in this overweight to obese, middle-aged cohort of males with low time resources. Thus, the main practical application of our finding might be that in general overweight-obese people can freely choose their preferred exercise type (HIIT-END or HIT-RT) to improve their cardiometabolic health, while investing an amount of time that should be feasible for everybody. Trial Registrations: NCT01406730, NCT01766791., (Copyright © 2020 Tuttor, von Stengel, Kohl, Lell, Scharf, Uder, Wittke and Kemmler.)- Published
- 2020
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37. Effects of Conventional Uric Acid-Lowering Therapy on Monosodium Urate Crystal Deposits.
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Ellmann H, Bayat S, Araujo E, Manger B, Kleyer A, Cavallaro A, Lell M, Schenker H, Simon D, Tascilar K, Baraf HSB, Schett G, and Rech J
- Subjects
- Aged, Alcohol Drinking, Allopurinol therapeutic use, Benzbromarone therapeutic use, Febuxostat therapeutic use, Female, Fructose, Gout diagnostic imaging, Humans, Male, Meat, Middle Aged, Prospective Studies, Purines, Shellfish, Tomography, X-Ray Computed, Uricosuric Agents therapeutic use, Diet Therapy, Foot Joints diagnostic imaging, Gout therapy, Gout Suppressants therapeutic use, Uric Acid blood
- Abstract
Objective: Few studies have systematically and quantitatively addressed the impact of urate-lowering therapy on monosodium urate (MSU) deposits. This study was undertaken to analyze the effect of lifestyle measures and conventional urate-lowering therapy on MSU deposits in patients with gout., Methods: In this prospective study, subjects with gout according to the American College of Rheumatology/European League Against Rheumatism classification criteria and presence of MSU deposits seen on dual-energy computed tomography (DECT) scans received either lifestyle intervention or conventional urate-lowering therapy for a mean period of 18 months before a follow-up DECT scan. Detected MSU deposits were quantified by volumetric measurement and validated by semiquantitative scoring, and baseline and follow-up measurements were compared., Results: Baseline and follow-up DECT scans were available for all 83 subjects. Six subjects discontinued treatment, and 77 subjects underwent a lifestyle intervention (n = 24) or were treated with allopurinol (n = 29), febuxostat (n = 22), or benzbromarone (n = 2) over the entire observation period. The mean serum uric acid (UA) level decreased from 7.2 to 5.8 mg/dl in the overall population. In patients who discontinued treatment, no change in MSU deposits or serum UA levels was observed. The burden of MSU deposits significantly decreased in patients undergoing lifestyle intervention (MSU volume P = 0.007; MSU score P = 0.001), and in patients treated with allopurinol (MSU volume and score P < 0.001) or febuxostat (MSU volume P < 0.001; MSU score P = 0.001). No significant decline in MSU deposits was noted in patients who discontinued treatment., Conclusion: These data show that lifestyle intervention and xanthine oxidase inhibitors significantly decrease the MSU deposit burden. Hence, conventional gout therapy not only lowers serum UA levels, but also reduces pathologic MSU deposits., (© 2019 University Erlangen. Arthritis & Rheumatology published by Wiley Periodicals, Inc. on behalf of American College of Rheumatology.)
- Published
- 2020
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38. Advanced Modeled Iterative Reconstruction (ADMIRE) Facilitates Radiation Dose Reduction in Abdominal CT.
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Ellmann S, Kammerer F, Allmendinger T, Hammon M, Janka R, Lell M, Uder M, and Kramer M
- Subjects
- Aged, Algorithms, Cohort Studies, Female, Humans, Male, Middle Aged, Software, Abdomen diagnostic imaging, Radiation Dosage, Radiographic Image Interpretation, Computer-Assisted, Tomography, X-Ray Computed
- Abstract
Rationale and Objectives: This study aimed to determine the potential degree of radiation dose reduction achievable using Advanced Modeled Iterative Reconstruction (ADMIRE) in abdominal computed tomography (CT) while maintaining image quality. Moreover, this study compared differences in image noise reduction of this iterative algorithm with radiation dose reduction., Methods: Eleven consecutive patients scheduled for abdominal CT were scanned according to our institute's standard protocol (100 kV, 289 reference mAs). Using a proprietary reconstruction software, CT images of these patients were reconstructed as either full-dose weighted filtered back projections or with simulated radiation dose reductions down to 10% of the full-dose level and ADMIRE at either strength 3 or strength 5. Images were marked with arrows pointing on anatomic structures of the abdomen, differing in their contrast to the surrounding tissue. Structures were grouped into high-, medium-, and low-contrast subgroups. In addition, the intrinsic noise of these structures was measured. That followed, image pairs were presented to observers, with five readers assessing image quality using two-alternative-forced-choice comparisons. In total, 3000 comparisons were performed that way., Results: Both ADMIRE 3 and 5 decreased noise of the anatomic structures significantly compared to the filtered back projection, with an additional significant difference between ADMIRE 3 and 5. Radiation dose reduction potential for ADMIRE ranged from 29.0% to 53.5%, with no significant differences between ADMIRE 3 and 5 within the contrast subgroups.The potential levels of radiation dose reduction for ADMIRE 3 differed significantly between high-, medium-, and low-contrast structures, whereas for ADMIRE 5, there was only a significant difference between the high- and the medium-contrast subgroups., Conclusion: Although ADMIRE 5 permits significantly higher noise reduction potential than ADMIRE 3, it does not facilitate higher levels of radiation dose reduction. ADMIRE nonetheless holds remarkable potential for radiation dose reduction, which features a certain dependency on the contrast of the structure of interest. Applying ADMIRE with a strength of 3 in abdominal CT may permit radiation dose reduction of about 30%., (Copyright © 2018 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.)
- Published
- 2018
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39. Testing of Alignment Parameters for Ancient Samples: Evaluating and Optimizing Mapping Parameters for Ancient Samples Using the TAPAS Tool.
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Taron UH, Lell M, Barlow A, and Paijmans JLA
- Abstract
High-throughput sequence data retrieved from ancient or other degraded samples has led to unprecedented insights into the evolutionary history of many species, but the analysis of such sequences also poses specific computational challenges. The most commonly used approach involves mapping sequence reads to a reference genome. However, this process becomes increasingly challenging with an elevated genetic distance between target and reference or with the presence of contaminant sequences with high sequence similarity to the target species. The evaluation and testing of mapping efficiency and stringency are thus paramount for the reliable identification and analysis of ancient sequences. In this paper, we present 'TAPAS', (Testing of Alignment Parameters for Ancient Samples), a computational tool that enables the systematic testing of mapping tools for ancient data by simulating sequence data reflecting the properties of an ancient dataset and performing test runs using the mapping software and parameter settings of interest. We showcase TAPAS by using it to assess and improve mapping strategy for a degraded sample from a banded linsang ( Prionodon linsang ), for which no closely related reference is currently available. This enables a 1.8-fold increase of the number of mapped reads without sacrificing mapping specificity. The increase of mapped reads effectively reduces the need for additional sequencing, thus making more economical use of time, resources, and sample material., Competing Interests: The authors declare no conflict of interest.
- Published
- 2018
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40. Diagnostics and therapy of vestibular schwannomas - an interdisciplinary challenge.
- Author
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Rosahl S, Bohr C, Lell M, Hamm K, and Iro H
- Abstract
Vestibular schwannomas (VS) expand slowly in the internal auditory canal, in the cerebellopontine angle, inside the cochlear and the labyrinth. Larger tumors can displace and compress the brainstem. With an annual incidence of 1:100,000 vestibular schwannoma represent 6-7% of all intracranial tumors. In the cerebellopontine angle they are by far the most neoplasm with 90% of all lesions located in this region. Magnetic resonance imaging (MRI), audiometry, and vestibular diagnostics are the mainstays of the clinical workup for patients harboring tumors. The first part of this paper delivers an overview of tumor stages, the most common grading scales for facial nerve function and hearing as well as a short introduction to the examination of vestibular function. Upholding or improving quality of life is the central concern in counseling and treating a patient with vestibular schwannoma. Preservation of neuronal function is essential and the management options - watchful waiting, microsurgery and stereotactic radiation - should be custom-tailored to the individual situation of the patient. Continuing interdisciplinary exchange is important to monitor treatment quality and to improve treatment results. Recently, several articles and reviews have been published on the topic of vestibular schwannoma. On the occasion of the 88
th annual meeting of the German Society of Oto-Rhino-Laryngology, Head and Neck surgery a special volume of the journal "HNO" will be printed. Hence this presentation has been designed to deviate from the traditional standard which commonly consists of a pure literature review. The current paper was conceptually woven around a series of interdisciplinary cases that outline examples for every stage of the disease that show characteristic results for management options to date. Systematic clinical decision pathways have been deduced from our experience and from results reported in the literature. These pathways are graphically outlined after the case presentations. Important criteria for decision making are size and growth rate of the tumor, hearing of the patient and the probability of total tumor resection with preservation of hearing and facial nerve function, age and comorbidity of the patient, best possible control of vertigo and tinnitus and last but not least the patient's preference and choice. In addition to this, the experience and the results of a given center with each treatment modality will figure in the decision making process. We will discuss findings that are reported in the literature regarding facial nerve function, hearing, vertigo, tinnitus, and headache and reflect on recent studies on their influence on the patient's quality of life. Vertigo plays an essential role in this framework since it is an independent predictor of quality of life and a patient's dependence on social welfare. Pathognomonic bilateral vestibular schwannomas that occur in patients suffering from neurofibromatosis typ-2 (NF2) differ from spontaneous unilateral tumors in their biologic behavior. Treatment of neurofibromatosis type-2 patients requires a multidisciplinary team, especially because of the multitude of separate intracranial and spinal lesions. Off-label chemotherapy with Bevacizumab can stabilize tumor size of vestibular schwannomas and even improve hearing over longer periods of time. Hearing rehabilitation in NF2 patients can be achieved with cochlear and auditory brainstem implants., Competing Interests: The authors declare that they have no competing interests.- Published
- 2017
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41. Prediction of fluoroscopic angulations for transcatheter aortic valve implantation by CT angiography: influence on procedural parameters.
- Author
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Hell MM, Biburger L, Marwan M, Schuhbaeck A, Achenbach S, Lell M, Uder M, and Arnold M
- Subjects
- Aged, Aged, 80 and over, Cohort Studies, Female, Fluoroscopy methods, Humans, Male, Postoperative Complications mortality, Postoperative Complications physiopathology, Predictive Value of Tests, Preoperative Care methods, Prognosis, Retrospective Studies, Risk Assessment, Severity of Illness Index, Statistics, Nonparametric, Survival Rate, Treatment Outcome, Aortic Valve Stenosis diagnostic imaging, Aortic Valve Stenosis surgery, Computed Tomography Angiography methods, Transcatheter Aortic Valve Replacement methods
- Abstract
Aims: Repeated angiograms to achieve an exactly orthogonal visualization of the aortic valve plane can substantially contribute to the total contrast amount required for transcatheter aortic valve implantation (TAVI). We investigated whether pre-procedural identification of an optimal fluoroscopic projection by cardiac computed tomography (CT) can significantly reduce the amount of a procedure-related contrast agent compared with angiographic determination of suitable angulations., Methods and Results: Eighty consecutive patients (81 ± 5 years, 55% male) with symptomatic severe aortic valve stenosis and normal renal function who underwent cardiac CT prior to TAVI were prospectively randomized. In 40 patients, a CT-predicted suitable angulation was used for the first aortic angiogram (CT cohort); in the other 40 patients, the first aortogram was acquired at LAO 10°/cranial 10 (angiography cohort). Additional aortograms were performed if no satisfactory view of the aortic valve plane was obtained. The number of aortograms needed to achieve a satisfactory fluoroscopic projection (1.2 ± 0.6 vs. 3.2 ± 1.7; P < 0.001) and the total amount of contrast agent per TAVI procedure were significantly lower in the CT cohort (95 ± 21 vs. 125 ± 36 mL; P < 0.001). Incidence of acute kidney injury was not significantly different. There was no significant difference regarding radiation dose, time of procedure, degree of post-procedural aortic regurgitation, complications and 30-day mortality between the cohorts., Conclusion: Pre-procedural identification of a suitable fluoroscopic projection by cardiac CT significantly reduces a procedural contrast agent volume required for TAVI., (Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2016. For permissions please email: journals.permissions@oup.com.)
- Published
- 2017
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42. Protein Supplementation to Augment the Effects of High Intensity Resistance Training in Untrained Middle-Aged Males: The Randomized Controlled PUSH Trial.
- Author
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Wittke A, von Stengel S, Hettchen M, Fröhlich M, Giessing J, Lell M, Scharf M, Bebenek M, Kohl M, and Kemmler W
- Subjects
- Adult, Body Composition drug effects, Dietary Supplements adverse effects, Food Hypersensitivity, Humans, Male, Middle Aged, Muscle, Skeletal drug effects, Muscle, Skeletal physiology, Proteins adverse effects, Resistance Training adverse effects, Exercise physiology, Muscle Strength drug effects, Proteins administration & dosage, Resistance Training methods
- Abstract
High intensity (resistance exercise) training (HIT) defined as a "single set resistance exercise to muscular failure" is an efficient exercise method that allows people with low time budgets to realize an adequate training stimulus. Although there is an ongoing discussion, recent meta-analysis suggests the significant superiority of multiple set (MST) methods for body composition and strength parameters. The aim of this study is to determine whether additional protein supplementation may increase the effect of a HIT-protocol on body composition and strength to an equal MST-level. One hundred and twenty untrained males 30-50 years old were randomly allocated to three groups: (a) HIT, (b) HIT and protein supplementation (HIT&P), and (c) waiting-control (CG) and (after cross-over) high volume/high-intensity-training (HVHIT). HIT was defined as "single set to failure protocol" while HVHIT consistently applied two equal sets. Protein supplementation provided an overall intake of 1.5-1.7 g/kg/d/body mass. Primary study endpoint was lean body mass (LBM). LBM significantly improved in all exercise groups ( p ≤ 0.043); however only HIT&P and HVHIT differ significantly from control ( p ≤ 0.002). HIT diverges significantly from HIT&P ( p = 0.017) and nonsignificantly from HVHIT ( p = 0.059), while no differences were observed for HIT&P versus HVHIT ( p = 0.691). In conclusion, moderate to high protein supplementation significantly increases the effects of a HIT-protocol on LBM in middle-aged untrained males.
- Published
- 2017
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43. Noise Reduction in Abdominal Computed Tomography Applying Iterative Reconstruction (ADMIRE).
- Author
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Schaller F, Sedlmair M, Raupach R, Uder M, and Lell M
- Subjects
- Adult, Aged, Aged, 80 and over, Algorithms, Artifacts, Contrast Media, Humans, Middle Aged, Radiation Dosage, Subtraction Technique, Radiographic Image Interpretation, Computer-Assisted methods, Tomography, X-Ray Computed methods
- Abstract
Rationale and Objectives: The study aimed to compare image quality of filtered back projection (FBP) and iterative reconstruction (advanced modeled iterative reconstruction, ADMIRE) in contrast-enhanced computed tomography (CT) of the abdomen, and to assess the differences of reconstructions according to these methods. It also aimed to investigate the potential for noise reduction of ADMIRE for different reconstructed slice thicknesses., Materials and Methods: CT data of the abdomen and pelvis were acquired using a 128-slice single-source CT system using automated kV selection and tube current adaption based on patients' anatomy. Raw data sets from patients scanned at 100 kV were selected, and images were reconstructed with slice thicknesses of 1 mm, 3 mm, and 5 mm, both with FBP and ADMIRE. Filter strength F1, F3, and F5 of the ADMIRE algorithm and the corresponding reconstruction kernels were used. In total, 58 raw data sets from 17 patients were used to reconstruct from the same raw data FBP and ADMIRE images, representing identical body regions. Identical regions of interest were placed at the same position of up to four images and image noise was measured. Differences of reconstructed images and detail preservation were tested using an image subtraction technique, and subjective image quality was assessed using a 5-point Likert scale., Results: On average, for 1-mm slice thickness, noise reduction was 9.15% ± 2.4% with filter strength level F1, 30.2% ± 3.4% with F3, and 54.4% ± 7.0% with F5 as compared to FBP. For a slice thickness of 3 mm, noise reduction was 8.5% ± 3.7% with F1, 28.6% ± 3.9% with F3, and 52.2% ± 9.1% with F5. For 5 mm, the corresponding values are 8.9% ± 2.7%, 31.4% ± 2.8%, and 52.7% ± 7.7%. On subtraction images, edge information of tissue classes with a high attenuation gradient was found, but structures with small differences in attenuation were not detectable on subtraction images, confirming that no relevant details were lost in the iterative reconstruction process., Conclusions: ADMIRE is able to reduce image noise considerably (up to 50%) without any obvious negative impact on lesion depiction as assessed visually. Noise reduction of ADMIRE seems to be independent of slice thickness., (Copyright © 2016 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.)
- Published
- 2016
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44. Chronic recurrent multifocal osteomyelitis in association with pyoderma gangraenosum.
- Author
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Wurm MC, Brecht I, Lell M, Brunner K, Mitsimponas KT, Chada M, Jahn J, Neukam FW, and von Wilmowsky C
- Subjects
- Adolescent, Child, Chronic Disease, Female, Germany, Humans, Recurrence, Osteomyelitis complications, Pyoderma complications
- Abstract
Background: Chronic recurrent multifocal osteomyelitis (CRMO) is a rare acquired inflammatory skeletal disorder of unknown origin. CRMO was first described by Gideon in 1972 and mainly affects children and young adults of female gender. The CRMO is part of the clinical picture of non-bacterial Osteomyelitis (NBO) and typically presents a relapsing recurring course with both remission and spontaneous exacerbation. CRMO is typically encountered in the limbs and the metaphysis of long bones in particular. Usually the clinical symptoms include painful swellings of the affected regions. This case report describes the rare case of a CRMO of the mandible in association with pyoderma gangraenosum., Case Presentation: A 14-year old female caucasian patient, residing in the south of Germany, presented in the oncological outpatient clinic of our Department of Paediatrics and Adolescent Medicine in June 2014 complaining of increasing neck pain and progressive swelling at her left cheek ongoing for about 6 weeks. These symptoms had been occurring quarterly for 4 years, but had never been as pronounced. Blood biochemistry showed a moderately elevated CRP (35 mg/l) and a significantly increased blood sedimentation rate (BSR 48/120 mm). The panoramic radiograph, however, revealed a bone alteration in the left mandibular region. Further investigations confirmed the diagnosis of CRMO., Conclusion: The present case underlines the fact that rare diseases might occasionally present with even more rare symptoms. These occasions can obviously be considered to present a considerable diagnostic challenge.
- Published
- 2016
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45. Development of a Dual-Energy Computed Tomography Scoring System for Measurement of Urate Deposition in Gout.
- Author
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Bayat S, Aati O, Rech J, Sapsford M, Cavallaro A, Lell M, Araujo E, Petsch C, Stamp LK, Schett G, Manger B, and Dalbeth N
- Subjects
- Aged, Female, Humans, Image Processing, Computer-Assisted, Male, Middle Aged, Gout diagnostic imaging, Tomography, X-Ray Computed methods, Uric Acid analysis
- Abstract
Objective: To develop a semiquantitative dual-energy computed tomography (DECT) scoring system for measurement of urate deposition in gout., Methods: Following a structured review of images, a semiquantitative DECT urate scoring method for foot/ankle scans was developed for testing. This method included 4 regions, each scored 0-3, with a maximum total DECT urate score of 12. DECT scans from 224 patients (182 with gout, 42 without gout) were scored by 2 independent readers. Automated urate volumes were also measured. Paired scans from 8 patients receiving pegloticase were analyzed, and a timing exercise was undertaken. The properties of the DECT urate score were analyzed according to the Outcome Measures in Rheumatology (OMERACT) filter., Results: The interreader intraclass correlation coefficient (95% confidence interval) for the DECT urate score was 0.98 (0.97-0.98). All scored regions contributed to the total DECT urate score. DECT urate scores and volumes were highly correlated (r = 0.91, P < 0.0001). Both DECT urate scores and volumes discriminated between gout and nongout control participants and between the tophaceous gout, nontophaceous gout, and control groups. Compared with urate volume, the DECT urate score had greater ability to discriminate between responders and nonresponders to pegloticase therapy (P < 0.001 for DECT urate score and P > 0.05 for volume). The mean ± SD time required for the DECT urate score was 121 ± 2 seconds and for urate volume was 240 ± 2 seconds (P = 2 × 10(-31) )., Conclusion: We have developed a novel semiquantitative DECT scoring method for measurement of urate deposition in the feet/ankles. This method fulfills many aspects of the OMERACT filter., (© 2016, American College of Rheumatology.)
- Published
- 2016
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46. Intra-abdominal localized hyaline-vascular Castleman disease: imaging characteristics and management of a rare condition.
- Author
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Vassos N, Raptis D, Lell M, Klein P, Perrakis A, Köhler J, Croner RS, Hohenberger W, and Agaimy A
- Published
- 2016
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47. Improved Image Quality in Head and Neck CT Using a 3D Iterative Approach to Reduce Metal Artifact.
- Author
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Wuest W, May MS, Brand M, Bayerl N, Krauss A, Uder M, and Lell M
- Subjects
- Adult, Aged, Aged, 80 and over, Contrast Media, Female, Humans, Iopamidol analogs & derivatives, Male, Middle Aged, Sensitivity and Specificity, Algorithms, Artifacts, Dental Restoration, Permanent, Image Enhancement methods, Image Processing, Computer-Assisted methods, Imaging, Three-Dimensional methods, Metals, Mouth Neoplasms diagnostic imaging, Oropharyngeal Neoplasms diagnostic imaging, Tomography, X-Ray Computed methods
- Abstract
Background and Purpose: Metal artifacts from dental fillings and other devices degrade image quality and may compromise the detection and evaluation of lesions in the oral cavity and oropharynx by CT. The aim of this study was to evaluate the effect of iterative metal artifact reduction on CT of the oral cavity and oropharynx., Materials and Methods: Data from 50 consecutive patients with metal artifacts from dental hardware were reconstructed with standard filtered back-projection, linear interpolation metal artifact reduction (LIMAR), and iterative metal artifact reduction. The image quality of sections that contained metal was analyzed for the severity of artifacts and diagnostic value., Results: A total of 455 sections (mean ± standard deviation, 9.1 ± 4.1 sections per patient) contained metal and were evaluated with each reconstruction method. Sections without metal were not affected by the algorithms and demonstrated image quality identical to each other. Of these sections, 38% were considered nondiagnostic with filtered back-projection, 31% with LIMAR, and only 7% with iterative metal artifact reduction. Thirty-three percent of the sections had poor image quality with filtered back-projection, 46% with LIMAR, and 10% with iterative metal artifact reduction. Thirteen percent of the sections with filtered back-projection, 17% with LIMAR, and 22% with iterative metal artifact reduction were of moderate image quality, 16% of the sections with filtered back-projection, 5% with LIMAR, and 30% with iterative metal artifact reduction were of good image quality, and 1% of the sections with LIMAR and 31% with iterative metal artifact reduction were of excellent image quality., Conclusions: Iterative metal artifact reduction yields the highest image quality in comparison with filtered back-projection and linear interpolation metal artifact reduction in patients with metal hardware in the head and neck area., (© 2015 by American Journal of Neuroradiology.)
- Published
- 2015
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48. Imaging the Parasinus Region with a Third-Generation Dual-Source CT and the Effect of Tin Filtration on Image Quality and Radiation Dose.
- Author
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Lell MM, May MS, Brand M, Eller A, Buder T, Hofmann E, Uder M, and Wuest W
- Subjects
- Humans, Radiation Dosage, Tin, Cone-Beam Computed Tomography methods, Image Processing, Computer-Assisted methods, Paranasal Sinuses diagnostic imaging
- Abstract
Background and Purpose: CT is the imaging technique of choice in the evaluation of midface trauma or inflammatory disease. We performed a systematic evaluation of scan protocols to optimize image quality and radiation exposure on third-generation dual-source CT., Materials and Methods: CT protocols with different tube voltage (70-150 kV), current (25-300 reference mAs), prefiltration, pitch value, and rotation time were systematically evaluated. All images were reconstructed with iterative reconstruction (Advanced Modeled Iterative Reconstruction, level 2). To individually compare results with otherwise identical factors, we obtained all scans on a frozen human head. Conebeam CT was performed for image quality and dose comparison with multidetector row CT. Delineation of important anatomic structures and incidental pathologic conditions in the cadaver head was evaluated., Results: One hundred kilovolts with tin prefiltration demonstrated the best compromise between dose and image quality. The most dose-effective combination for trauma imaging was Sn100 kV/250 mAs (volume CT dose index, 2.02 mGy), and for preoperative sinus surgery planning, Sn100 kV/150 mAs (volume CT dose index, 1.22 mGy). "Sn" indicates an additional prefiltration of the x-ray beam with a tin filter to constrict the energy spectrum. Exclusion of sinonasal disease was possible with even a lower dose by using Sn100 kV/25 mAs (volume CT dose index, 0.2 mGy)., Conclusions: High image quality at very low dose levels can be achieved by using a Sn100-kV protocol with iterative reconstruction. The effective dose is comparable with that of conventional radiography, and the high image quality at even lower radiation exposure favors multidetector row CT over conebeam CT., (© 2015 by American Journal of Neuroradiology.)
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- 2015
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49. Determining microvascular obstruction and infarct size with steady-state free precession imaging cardiac MRI.
- Author
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Wuest W, Lell M, May M, Scharf M, Schlundt C, Achenbach S, Uder M, and Schmid A
- Subjects
- Adult, Aged, Aged, 80 and over, Coronary Vessels pathology, Female, Gadolinium, Humans, Image Enhancement, Male, Middle Aged, Coronary Circulation, Magnetic Resonance Imaging, Cine methods, Microcirculation, Myocardial Infarction diagnosis, Myocardium pathology
- Abstract
Purpose: In cardiac MRI (cMRI) injection of contrast medium may be performed prior to the acquisition of cine steady-state free precession (SSFP) imaging to speed up the protocol and avoid delay before late Gadolinium enhancement (LGE) imaging. Aim of this study was to evaluate whether a condensed clinical protocol with contrast cine SSFP imaging is able to detect early microvascular obstruction (MO) and determine the infarct size compared to the findings of LGE inversion recovery sequences., Materials and Methods: The study complies with the Declaration of Helsinki and was performed following approval by the ethic committee of the University of Erlangen-Nuremberg. Written informed consent was obtained from every patient. 68 consecutive patients (14 females/54 males) with acute ST-elevation myocardial infarction (STEMI) treated by percutaneous coronary revascularization were included in this study. CMRI was performed 6.6±2 days after symptom onset and MO and infarct size in early contrast SSFP cine imaging were compared to LGE imaging., Results: MO was detected in 47/68 (69%) patients on cine SSFP and in 41/68 (60%) patients on LGE imaging. In 6 patients MO was found on cine SSFP imaging but was not detectable on LGE imaging. Infarct size on cine SSFP showed a strong agreement to LGE imaging (intraclass correlation coefficient [ICC] of 0.96 for enddiastolic, p<0.001 and 0.96 for endsystolic, p<0.001 respectively). Significant interobserver agreement was found measuring enddiastolic and endsystolic infarct size on cine SSFP imaging (p<0.01)., Conclusions: In patients after STEMI infarct size and presence of MO can be detected with contrast cine SSFP imaging. This could be an option in patients who are limited in their ability to comply with the demands of a cMRI protocol.
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- 2015
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50. Accuracy of prospectively ECG-triggered very low-dose coronary dual-source CT angiography using iterative reconstruction for the detection of coronary artery stenosis: comparison with invasive catheterization.
- Author
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Layritz C, Schmid J, Achenbach S, Ulzheimer S, Wuest W, May M, Ropers D, Klinghammer L, Daniel WG, Pflederer T, and Lell M
- Subjects
- Algorithms, Contrast Media, Coronary Stenosis diagnostic imaging, Female, Humans, Iohexol analogs & derivatives, Male, Middle Aged, Prospective Studies, Radiation Dosage, Cardiac Catheterization, Cardiac-Gated Imaging Techniques, Coronary Angiography methods, Coronary Stenosis diagnosis, Radiographic Image Interpretation, Computer-Assisted, Tomography, X-Ray Computed methods
- Abstract
Objective: To evaluate the image quality and diagnostic accuracy of very low-dose computed tomography (CT) angiography (CTA) for the evaluation of coronary artery stenosis., Background: Iterative reconstruction (IR) has shown to substantially reduce image noise and hence permit the use of very low-dose data acquisition protocols in coronary CTA., Methods: Fifty symptomatic patients with an intermediate likelihood for coronary artery disease underwent coronary CTA (heart rate: 59 ± 5 bpm, prospectively ECG-triggered axial acquisition, 100 kV, 160 mAs, 2 × 128 × 0.6 mm collimation, 60 mL contrast, 6 mL/s) prior to invasive coronary angiography. CTA images were reconstructed using both standard filtered back projection (FBP) and a raw data-based IR algorithm [Sinogram Affirmed Iterative Reconstruction (SAFIRE), Siemens Healthcare]. Subjective image quality (four-point Likert scale from 0 = non-diagnostic to 3 = excellent image quality), image noise, signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), as well as the presence of coronary stenosis >50% were independently determined by two observers., Results: The mean dose-length product was 46.8 ± 3.5 mGy cm (estimated effective dose 0.66 ± 0.05 mSv). IR led to significantly improved objective image quality compared with FBP (image noise: 41 ± 12 vs. 49 ± 11 HU, P < 0.0001; CNR: 16 ± 8 vs. 12 ± 4, P < 0.0001; SNR: 13 ± 7 vs. 10 ± 3, P < 0.0001). Four coronary segments were not evaluable on FBP data, whereas all segments showed diagnostic image quality with IR. To detect significant coronary stenosis, sensitivity, specificity, positive predictive value, and negative predictive value were 69% (11/16), 97% (175/180), 69% (11/16), and 97% (175/180) per vessel with FBP data sets, respectively. With IR data sets, the corresponding values were 81% (13/16), 97% (178/184), 68% (13/19), and 98% (178/181). These differences were not statistically significant (P = 0.617)., Conclusions: Raw data-based IR significantly improves image quality in very low-dose prospectively ECG-triggered coronary dual-source CTA when compared with standard reconstruction using FBP., (Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2014. For permissions please email: journals.permissions@oup.com.)
- Published
- 2014
- Full Text
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