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Bildgebung in der Beckenchirurgie

Holger Keil, Paul Grützner, Jochen Franke
2018 OP-Journal  
Keil H et al. Bildgebung in der … OP-JOURNAL 2018; 34: 5-16 Dieses Dokument wurde zum persönlichen Gebrauch heruntergeladen. Vervielfältigung nur mit Zustimmung des Verlages.  ... 
doi:10.1055/s-0044-100157 fatcat:vbjzqmefefbwvgwlrxfswprzsi

Abstract: Automatic Plane Adjustment in Surgical Cone Beam CT-volumes [chapter]

Celia Martín Vicario, Florian Kordon, Felix Denzinger, Markus Weiten, Sarina Thomas, Lisa Kausch, Jochen Franke, Holger Keil, Andreas Maier, Holger Kunze
2021 Informatik aktuell  
Cone beam computed tomography (CBCT) is used intra-operatively to assess the result of surgery. Due to limitations of patient positioning and the operating theater in general, the acquisition usually cannot be performed such that the axis-aligned multiplanar reconstructions (MPR) of the volume match the anatomically oriented MPRs. This needs to be corrected manually, which is a time-consuming and complex task and requires the surgeon to interact with non-sterile equipment. To this end, this
more » ... y investigates a fully-automatic solution to directly regress the standard plane parameters from a CBCT volume of the calcaneus and ankle regions. A PoseNet convolutional neural network (CNN) is adapted and trained, comparing a 6D-, Euler angle-and quaternionbased approach to represent the plane rotation [1]. In addition, a cost function is optimized to incorporate orientation constraints. The best-performing CNN -which uses the 6D representation -estimates the plane normal with a median accuracy of 5 • , the in-plane rotation with a median accuracy of 6 • , and the position with a median accuracy of 6 mm. The inference time is less than 0.05 s. References
doi:10.1007/978-3-658-33198-6_40 fatcat:h63fgtvlzrdsdpf2jhs76rjaly

Optimal Timing of Extracorporeal Shock Wave Treatment to Protect Ischemic Tissue

Matthias A. Reichenberger, Holger Keil, Wolf Mueller, Christel Herold-Mende, Romed Meirer, Martha Maria Gebhard, Günter Germann, Holger Engel
2011 Annals of Plastic Surgery  
Enhancement of flap survival through extracorporeal shock wave treatment (ESWT) is a promising new technique; however, no attempt has been made to define the optimal time point and frequency of ESWT to optimize treatment with ESWT for ischemic indications. Twenty-eight male Wistar rats were randomized into 4 groups and an oversized, random-pattern flap was raised and reattached in place in each animal. ESWT was applied 7 days before (group E7) or immediately after the surgical intervention
more » ... p E0). The third group was treated with ESWT 7 days before and additionally immediately after the operation (group E7/0). The fourth group served as a control group and did not receive any ESWT (group C). Seven days after flap harvest the results of flap survival, perfusion, microvessel density, and vascular endothelial growth factor concentrations were assessed. Flap survival was significantly increased in all ESWT groups as compared with the control group. The groups (E7 and E0) that received ESWT pre-or postoperatively showed a significant increase in flap perfusion and microvessel density. Combined pre-and postoperative ESWT application (group E0/E7) did not demonstrate a cumulative effect in any evaluation. In this study, we were be able to prove the effectiveness of ESWT in the protection of ischemic tissue flaps. This study suggests that single postoperative application is the most efficacious protocol for clinical applications of ESWT in the treatment of ischemic tissue.
doi:10.1097/sap.0b013e3182085880 pmid:21587053 fatcat:4dtjcxfkbzgz7p3yu2fxnl7cu4

Intra-operative imaging in trauma surgery

Holger Keil, Nils Beisemann, Benedict Swartman, Sven Yves Vetter, Paul Alfred Grützner, Jochen Franke
2018 EFORT Open Reviews  
Keil declares grants from Siemens Healthcare AG; payment for lectures from Brainlab AG, activities outside the submitted work. P.  ... 
doi:10.1302/2058-5241.3.170074 pmid:30662762 pmcid:PMC6335592 fatcat:rucj73n24jf6hfbw4jhqcfe5i4

Temperature induced friction increase in friction test and forming demonstrator for sheet metal forming

Jan Filzek, Daniel Keil, Holger Schröder
2021 ESAFORM 2021  
High process stability is needed in sheet metal forming industry. This can be achieved by predicting and controlling the transient process and temperature variation, especially at start of production. In this connection, the temperature induced friction changing plays a significant role because it leads to product failures. The handling of the transient friction effects is currently done reactively, based on the individual experience of the machine operators. In future, those transient effects
more » ... eed to be controlled. This paper shows initially an analysis of the temperature induced friction increase in a well-known and proven flat strip drawing test. Different tribological systems were tested at tool temperatures between 20 and 80 °C. The temperature increase results in a higher friction of up to 77 %. Several influences on friction increase will be presented. These friction influences were verified afterwards with a heated forming demonstrator under laboratory conditions.
doi:10.25518/esaform21.3732 fatcat:fwn5rjgu4fctdknqm3ukcxww4i

Preoperative shock wave treatment enhances ischemic tissue survival, blood flow and angiogenesis in a rat skin flap model

Holger Keil, Wolf Mueller, Christel Herold-Mende, Martha Maria Gebhard, Günter Germann, Holger Engel, Matthias A. Reichenberger
2011 International Journal of Surgery  
Author contribution Holger Keil performed most experiments and wrote the manuscript together with MAR.  ...  Gebhard and Holger Engel performed some experiments and provided surgical support Günter Germann provided coordination and mentorship and drafted manuscript Matthias A.  ... 
doi:10.1016/j.ijsu.2011.01.003 pmid:21256991 fatcat:v5tzqxdzvvc2jpikik6wicgl4e

Comment on "Sediment research, management and policy—a decade of JSS"

Martin Keil, Jochen Großmann, Holger Weiß
2011 Journal of Soils and Sediments  
doi:10.1007/s11368-011-0334-7 fatcat:2flqczl3e5bxvahj7nd4gxpa24

CREB1Genotype Modulates Adaptive Reward-Based Decisions in Humans

Claudia Wolf, Holger Mohr, Esther K. Diekhof, Henning Vieker, Roberto Goya-Maldonado, Sarah Trost, Bernd Krämer, Maria Keil, Elisabeth B. Binder, Oliver Gruber
2015 Cerebral Cortex  
fMRI Task Previous studies have used this (Trost et al. 2014 ) and similar versions (Diekhof and Gruber 2010; Diekhof, Keil, et al. 2012; Diekhof, Nerenberg, et al. 2012 ) of our event-related fMRI task  ...  Suzuki et al. 2011) and their activity contributes to the neural networks related to adaptive reward-based decision-making (Diekhof and Gruber 2010; Liu et al. 2011; Diekhof, Kaps, et al. 2012; Diekhof, Keil  ... 
doi:10.1093/cercor/bhv104 pmid:26045569 fatcat:gshhwuhgh5a7xbj2c2bilyi6xa

Acellularization-Induced Changes in Tensile Properties Are Organ Specific - An In-Vitro Mechanical and Structural Analysis of Porcine Soft Tissues

Stefan Schleifenbaum, Torsten Prietzel, Gabriela Aust, Andreas Boldt, Sebastian Fritsch, Isabel Keil, Holger Koch, Robert Möbius, Holger A. Scheidt, Martin F. X. Wagner, Niels Hammer, Adam J. Engler
2016 PLoS ONE  
Introduction Though xenogeneic acellular scaffolds are frequently used for surgical reconstruction, knowledge of their mechanical properties is lacking. This study compared the mechanical, histological and ultrastructural properties of various native and acellular specimens. Discussion Acellularization induces changes in the tensile properties of soft tissues. Some of these changes appear to be organ specific. Loss of cross-linking type I collagen may indicate increased mechanical strength due
more » ... o decreasing transverse forces acting upon the scaffolds, whereas fibronectin loss may be related to decreased load-bearing capacity. Potentially, the alterations in tissue mechanics are linked to organ function and to the interplay of cells and the extracellular matrix, which is different in hollow organs when compared to skin.
doi:10.1371/journal.pone.0151223 pmid:26960134 pmcid:PMC4784745 fatcat:fyqdkp4dircy7mj2s6kjfgc5ze

Comparison of three different reduction methods of the ankle mortise in unstable syndesmotic injuries

Sven Yves Vetter, Nils Beisemann, Holger Keil, Marc Schnetzke, Benedict Swartman, Jochen Franke, Paul Alfred Grützner, Maxim Privalov
2019 Scientific Reports  
In order to achieve a clinically satisfying result and to prevent posttraumatic osteoarthritis in the treatment of unstable syndesmotic injuries, anatomically correct reduction is crucial. The objective of the study was to investigate three different reduction methods of the ankle mortise in unstable syndesmotic injuries. In a specimen model with 38 uninjured fresh-frozen lower legs, a complete syndesmotic dissection was performed. The ankle mortise was reduced with either a collinear reduction
more » ... clamp, a conventional reduction forceps or manually with crossing K-wires. The reduction clamps and the K-wires were placed in a 0°-angle to the leg axis. The clamps were positioned on the posterolateral ridge of the fibula 20 mm proximal to the ankle joint line. A cone beam computed tomography was performed after dissection and after each reduction. Tibio-fibular distances and angles were determined. Despite significant differences in terms of overcompression (0.09-0.33 mm; p = 0.000-0.063) and the slight external rotation (0.29-0.47°; p = 0.014-0.07), the results show a satisfying reduction of the ankle mortise. There were no considerable differences between the reduction methods. It can therefore be concluded that the ankle mortise can be reduced with any of the methods used, but that the positioning and the contact pressure must be considered.
doi:10.1038/s41598-019-51988-y pmid:31659196 pmcid:PMC6817893 fatcat:ntqsvgqccrdinkksjrtubnzbzq

CD11c+ dendritic cells mediate antigen‐specific suppression in extracorporeal photopheresis

Holger Hackstein, Annika Kalina, Britta Dorn, Isabell Sofia Keil, Nelli Baal, Gabriela Michel, Cornelia Brendel, Andreas Neubauer, Thilo Jakob, Gregor Bein
2020 Clinical and Experimental Immunology  
Extracorporeal photopheresis (ECP) represents one of the most widespread and effective cell therapies for graft-versus-host disease and other T cell-mediated disorders. However, the key factors affecting the therapeutic efficacy of ECP remain unclear. We hypothesized that therapeutic effects are mediated by ECP-treated antigen presenting dendritic cells (DC). To test this hypothesis, we used the experimental model of contact hypersensitivity (CHS). The ECP's therapeutic activity improved when
more » ... e total cell dose of the ECP-treated cells was increased. We used different haptens during sensitization to demonstrate that the anti-inflammatory activity of ECP is antigen-specific. This confirmed the hypothesis that professional antigen-presenting cells are involved in the mode of action. Also, the ECP's therapeutic activity was abrogated by the depletion of CD11c+ DC which represents less than 1% of all the ECP-exposed cells. Finally, we confirm the critical importance of CD11c+ DC for ECP activity by showing that only a few purified CD11c+ DC are sufficient to mediate its therapeutic effect. The finding, that ECP-treated, physiologic antigen-presenting DC alone mediate antigen-specific modulation of a pathological immune response may translate in better targeted interventions when treating patients.
doi:10.1111/cei.13539 pmid:33073358 fatcat:fufqttsu3vc4rpcabu6qjszlly

Ruxolitinib therapy for myelofibrosis in Austria

Maria-Theresa Krauth, Sonja Burgstaller, Veronika Buxhofer-Ausch, Günther Gastl, Klaus Geissler, Felix Keil, Peter Krippl, Thomas Melchardt, Andreas Petzer, Holger Rumpold, Thamer Sliwa, Stefan Wöhrer (+2 others)
2018 Wiener Klinische Wochenschrift  
The oral Janus associated kinase (JAK1/2) inhibitor ruxolitinib has been available for treatment of patients with intermediate or high-risk myelofibrosis in Europe since 2012. Since its introduction, the expertise of prescribing doctors with respect to ruxolitinib function, efficacy and adverse effects has consistently been augmented, resulting in therapy modalities that are better tailored to individual patients as well as in increased safety of the treatment. The present consensus on
more » ... ib therapy management has been elaborated by Austrian experts in myeloproliferative neoplasms in line with international treatment guidelines. Our recommendations aim to contribute to an improved management of patients with myelofibrosis treated with ruxolitinib.
doi:10.1007/s00508-018-1365-5 pmid:30043249 fatcat:i7al6mqy3bc4vga2u2fwjd76qa

Correction to: Ruxolitinib therapy formyelofibrosis in Austria

Maria-Theresa Krauth, Sonja Burgstaller, Veronika Buxhofer-Ausch, Günther Gastl, Klaus Geissler, Felix Keil, Peter Krippl, Thomas Melchardt, Andreas Petzer, Holger Rumpold, Thamer Sliwa, Stefan Wöhrer (+2 others)
2018 Wiener Klinische Wochenschrift  
doi:10.1007/s00508-018-1428-7 fatcat:auwh5yt5mfefxlh7wkykutsmja

Interobserver and intraobserver agreement of ligamentous injuries on conventional MRI after simple elbow dislocation

Marc Schnetzke, Svenja Schüler, Johannes Hoffend, Rainer Simon, Holger Keil, Felix Porschke, Stefan Studier-Fischer, Paul-Alfred Grützner, Thorsten Guehring
2017 BMC Musculoskeletal Disorders  
The primary objective of this study was to assess the interobserver and intraobserver agreement on ligamentous injuries on conventional magnetic resonance imaging (MRI) in acute simple elbow dislocation. The secondary objectives were to determine the interobserver agreement on the assessment of joint congruity, joint effusion, loose bodies and chondral lesions on conventional MRI. Methods: Conventional MRIs (1.5 Tesla, elbow specific surface coil) of 30 patients (40.7 years; range 14-72) with
more » ... mple elbow dislocations were evaluated by four blinded examiners. An analysis of the interobserver agreement of all raters and for several subgroups (radiologists, orthopaedics, experienced, non-experienced) was performed. The examiners assessed the integrity (intact, partial tear, complete tear) of the lateral collateral ligament (LCL), medial collateral ligament (MCL), extensor and flexor tendons, as well as the presence of joint congruity, joint effusion, loose bodies and chondral lesions. Agreement strength, correlation and proportion of exact agreement were determined for interobserver agreement, and intraobserver agreement analyses. Results: Interobserver agreement of all examiners was fair to moderate for collateral ligaments (LCL: 0.441, MCL: 0.275). Exact agreement of all raters was found in 33.3% for the LCL and in 26.7% for the MCL. The both experienced examiners showed highest agreement strength for the LCL (0.619) and the radiologists showed highest agreement strength for the MCL (0.627), the proportion of exact agreement was 60.0% in both categories. A high proportion of exact agreement regarding joint congruity (90%), joint effusion (100%), loose bodies (96.7%) and chondral lesion (80%) was found among the radiologists. The evaluation of the intraobserver agreement revealed slight to substantial agreement (0.227 to 0.718) for the collateral ligaments. Conclusions: This study shows difficulties in the evaluation of ligaments by conventional MRI technique as demonstrated by a weak inter-and intraobserver agreement. This should be the basis to develop new MRI quality standards with special focus on coronal oblique reconstructions to improve the evaluation of ligament injuries after simple elbow dislocations.
doi:10.1186/s12891-017-1451-2 pmid:28219360 pmcid:PMC5319117 fatcat:ovmzyh6wz5ezba4fmj2o3peez4

Trends in Cardiovascular Risk Factors Among Patients With Coronary Heart Disease

Christof Prugger, Jan Heidrich, Jürgen Wellmann, Ralf Dittrich, Stefan-Martin Brand, Ralph Telgmann, Günter Breithardt, Holger Reinecke, Hans Scheld, Peter Kleine-Katthöfer, Peter U. Heuschmann, Ulrich Keil
2012 Deutsches Ärzteblatt International  
►Cite this as: Prugger C, Heidrich J, Wellmann J, Dittrich R, Brand SM, Telgmann R, Breithardt G, Reinecke H, Scheld H, Kleine-Katthöfer P, Heuschmann P, Keil U: Trends in cardiovascular risk factors among  ...  Keil U: Das weltweite WHO-MONICA-Projekt: Ergebnisse und Aus- blick. Gesundheitswesen 2005; 67: 38-45. e16.  ...  Heuschmann, Ulrich Keil e10. Miettinen H, Lehto S, Salomaa V, et al.: Impact of diabetes on mortality after the first myocardial infarction.  ... 
doi:10.3238/arztebl.2012.0303 pmid:22611443 pmcid:PMC3355493 fatcat:igzhpr76ebfbzb6gppngzi4f2u
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