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Einleitung: Über das konkrete Ausmaß einer Neck-Dissection während der totalen Laryngektomie gibt es weder national noch international einen offiziellen Konsens in Form von Leitlinien. Dies hat einen individuellen und nicht-standardisierten Therapieplan in der chirurgischen Therapie des Halses beim fortgeschrittenen Larynxkarzinom zur Folge. Methoden: Wir untersuchten retrospektiv die Verläufe von 58 konsekutiven Patienten, die sich an der Charité wegen eines fortgeschrittenen Plattenepithelkarzinoms des Larynx einer totalen Laryngektomie mit beidseitiger Neck-Dissection unterzogen. Hierbei wurde zum einen das Nodal Yield des ipsilateralen Halses bzgl. Auswirkung auf Overall und Disease-free Survival untersucht. Zum anderen etablierten wir ein Klassifikationsschema des CT-basierten Mittelllinienbezugs des Primärtumors (Typ A "clear", B "involved", C "exceeded" und D "bilateral") und untersuchten die Relation zu kontralateraler Halslymphknoten-Metastasierung. Ergebnisse: Uni- und multivariate Regresssionsanalysen zeigten keinen signifikanten Einfluss des ipsilateralen Nodal Yields auf Overall- und Disease-free Survival (p < 0.05). Ein pN+-Hals zeigte einen negativen prognostischen Wert (OS: hazard ratio [HR] 0.179; p=0,013). In 10,3% zeigte sich ein p2Nc-Hals. Typ-D-tumoren haben eine Wahrscheinlichkeit von 23,5% kontralateral zu metastasieren. Typ-A-Tumoren unterliegen einer Risiko-Reduktion von 100% für kontralaterale Metastasierung. Schlussfolgerungen: Das ipsilaterale Nodal Yield einer Neck-Dissection in der Laryngektomie hat keinen Einfluss auf das Outcome. Bei Typ-A-Tumoren und klinisch unauffälligem kontralateralen Hals (<= cN2b) scheint eine kontralaterale Neck-Dissection nicht indiziert, was zur Reduktion von OP-Zeit und Komplikationsraten beitragen kann.Der Erstautor gibt keinen Interessenkonflikt an.

Velocity measurements were carried out in a cube filled with the liquid metal GaInSn using a dual plane, two-component ultrasound array Doppler velocimeter. The liquid metal was suddenly exposed to an azimuthal body force generated by a rotating magnetic field (RMF). The measurements show a similar flow structure compared to the case of the RMF-driven flow in a cylindrical container, in particular the so-called initial adjustment phase followed by an inertial phase which is dominated by inertial oscillations of the secondary flow. The interest was especially focused on the onset of unsteady flow regimes. The transition from the steady double vortex structure of the secondary flow to an oscillating regime was detected at a magnetic Taylor number of Ta > 1.3  105. A detailed analysis of the flow structure was done by means of the Proper Orthogonal Decomposition (POD). Corresponding numerical simulations were performed showing an excellent agreement with the experimental data.

Velocity measurements were carried out in a cube filled with the liquid metal GaInSn using a dual plane, two-component ultrasound array Doppler velocimeter. The liquid metal was suddenly exposed to an azimuthal body force generated by a rotating magnetic field (RMF). The measurements show a similar flow structure compared to the case of the RMF-driven flow in a cylindrical container, in particular the so-called initial adjustment phase followed by an inertial phase which is dominated by inertial oscillations of the secondary flow. The interest was especially focused on the onset of unsteady flow regimes. The transition from the steady double vortex structure of the secondary flow to an oscillating regime was detected at a magnetic Taylor number of Ta > 1.3  105. A detailed analysis of the flow structure was done by means of the Proper Orthogonal Decomposition (POD). Corresponding numerical simulations were performed showing an excellent agreement with the experimental data.

Velocity measurements were carried out in a cube filled with the liquid metal GaInSn using a dual plane, two-component ultrasound array Doppler velocimeter. The liquid metal was suddenly exposed to an azimuthal body force generated by a rotating magnetic field (RMF). The measurements show a similar flow structure compared to the case of the RMF-driven flow in a cylindrical container, in particular the so-called initial adjustment phase followed by an inertial phase which is dominated by inertial oscillations of the secondary flow. The interest was especially focused on the onset of unsteady flow regimes. The transition from the steady double vortex structure of the secondary flow to an oscillating regime was detected at a magnetic Taylor number of Ta > 1.3  105. A detailed analysis of the flow structure was done by means of the Proper Orthogonal Decomposition (POD). Corresponding numerical simulations were performed showing an excellent agreement with the experimental data.

Einleitung: Beim Vagusneurinom handelt es sich um einen seltenen gutartigen, neurogenen Tumor, der von den Schwann'schen Zellen ausgeht und im Kopf-/Halsbereich auftreten kann. Klinisch fallen die betroffenen Patienten mit einer langsam wachsenden, schmerzlosen zervikalen Schwellung auf. Gelegentlich können weitere Symptome wie Dysphonie und Dysphagie auftreten.Kasuistik: Wir berichten über den Fall eines 35-jährigen Patienten, der sich mit einer seit 4 Monaten größenprogredienten, symptomatischen linkszervikalen Raumforderung in unserer Poliklinik vorstellte. Der primäre Verdacht auf eine zervikale Echinococcuszyste beruhte auf einer auswärtigen MRT und Ultraschalluntersuchung. Die Serologie konnte eine Echinokokkose ausschließen.Es zeigte sich das Bild einer 185 x 115 x 69 mm messenden, vorwiegend zystoiden, spindelförmigen Raumforderung mit teils soliden Septierungen zervikal links im Verlauf des N. vagus. Eine weitere kleinere Raumforderung fand sich kaudal des Ganglions trigeminale mit konsekutiver Aufweitung des Foramen ovale. Die Exstirpation und histologische Sicherung der zervikalen Raumforderung erfolgte transzervikal über einen Neck-dissection-Zugang mit anschließender End-zu-End-Anastomosierung des N. vagus. Der histopathologische Befund bestätigte das Vorliegen eines Neurinoms.Der Erstautor gibt keinen Interessenkonflikt an.

Ultrasound velocity measurements were performed in a liquid metal flow (GaInSn) inside a cubic vessel. The flow was driven by the combined action of a rotating (RMF) and a travelling magnetic field (TMF) leading to an inherent three-dimensional electromagnetic force distribution in the fluid. As a result flow structures develop which are essentially determined by the frequency difference and the strength relation of both fields. The driving force is stationary for identical frequencies whereas it undergoes a slow temporal modulation in case of slightly varying frequencies. Beside the magnetic field parameter the alignment of the TMF’s to the fluid volume’s axis plays a crucial role. A novel ultrasound array system was used in the present study to measure two velocity components in two perpendicular planes (2d-2c) simultaneously. This contribution reports on the influence of axial alignment on the flow, and on the flow dynamics resulting from slightly different field frequencies of the RMF and the TMF.

Investigating the complex interaction of conductive fluids and magnetic fields is relevant for a variety of applications from basic research in magnetohydrodynamics (MHD) to modeling industrial processes involving metal melts, such as the crystal growth process in the photovoltaic industry. This enables targeted optimizations of the melt flow and allows to significantly increase the yield and energy efficiency of an industrial process. However, experimental studies in this field are often limited by the performance of flow instrumentation for opaque liquids. We present an ultrasound array Doppler velocimeter (UADV) for flow mapping in opaque liquids at room temperature. It is modular and flexible regarding its measurement configuration, for instance it allows capturing two velocity components in two planes (2d-2c). It uses up to 9 linear arrays with a total element count of 225, driven in a parallelized time division multiplex (TDM) scheme. A FPGA-based signal pre-processing allows to handle the massive data bandwidth of typ. 1.2 GB/s and enables a continuous and near-realtime operation of the measurement system. Combining the velocity information of multiple arrays necessitates precise knowledge of their relative geometric position. We present a novel method for spatial self-calibration by a mutual time of flight measurement that significantly reduces the alignment errors. The capabilities of the UADV system are demonstrated in an experiment for basic MHD research. A cubic plexiglas container (67mm3) is filled with a metal melt (GaInSn, melting point 10°C). The flow induced by time-varying rotating magnetic fields is captured with a temporal resolution of 250ms and an uncertainty of approx. 1% for the horizontal and vertical central cross-section of the cube (2d- 2c).

Ultrasound velocity measurements were performed in a liquid metal flow (GaInSn) inside a cubic vessel. The flow was driven by the combined action of a rotating (RMF) and a travelling magnetic field (TMF) leading to an inherent three-dimensional electromagnetic force distribution in the fluid. As a result flow structures develop which are essentially determined by the frequency difference and the strength relation of both fields. The driving force is stationary for identical frequencies whereas it undergoes a slow temporal modulation in case of slightly varying frequencies. Beside the magnetic field parameter the alignment of the TMF’s to the fluid volume’s axis plays a crucial role. A novel ultrasound array system was used in the present study to measure two velocity components in two perpendicular planes (2d-2c) simultaneously. This contribution reports on the influence of axial alignment on the flow, and on the flow dynamics resulting from slightly different field frequencies of the RMF and the TMF.

Investigating the complex interaction of conductive fluids and magnetic fields is relevant for a variety of applications from basic research in magnetohydrodynamics (MHD) to modeling industrial processes involving metal melts, such as the crystal growth process in the photovoltaic industry. This enables targeted optimizations of the melt flow and allows to significantly increase the yield and energy effciency of industrial processes. However, experimental studies in this field are often limited by the performance of flow instrumentation for opaque liquids. We present an ultrasound array Doppler velocimeter (UADV) for flow mapping in opaque liquids at room temperature. It is modular and flexible regarding its measurement configuration, for instance it allows capturing two velocity components in two planes (2d - 2c). It uses up to 9 linear arrays with a total element count of 225, driven in a parallelized time division multiplex (TDM) scheme. A FPGA-based signal pre-processing allows to handle the massive data bandwidth of typ. 1.2 GB/s and enables a continuous and near-realtime operation of the measurement system. The capabilities of the UADV system are demonstrated in a basic MHD research experiment with a metal melt (GaInSn) in a cubic container of (67 mm)³. The flow induced by a rotating magnetic field is captured with a temporal resolution of 250 ms for the horizontal and vertical central cross-section of the cube.

Investigating the complex interaction of conductive fluids and magnetic fields is relevant for a variety of applications from basic research in magnetohydrodynamics (MHD) to modeling industrial processes involving metal melts, such as the crystal growth process in the photovoltaic industry. This enables targeted optimizations of the melt flow and allows to significantly increase the yield and energy effciency of industrial processes. However, experimental studies in this field are often limited by the performance of flow instrumentation for opaque liquids. We present an ultrasound array Doppler velocimeter (UADV) for flow mapping in opaque liquids at room temperature. It is modular and flexible regarding its measurement configuration, for instance it allows capturing two velocity components in two planes (2d - 2c). It uses up to 9 linear arrays with a total element count of 225, driven in a parallelized time division multiplex (TDM) scheme. A FPGA-based signal pre-processing allows to handle the massive data bandwidth of typ. 1.2 GB/s and enables a continuous and near-realtime operation of the measurement system. The capabilities of the UADV system are demonstrated in a basic MHD research experiment with a metal melt (GaInSn) in a cubic container of (67 mm)³. The flow induced by a rotating magnetic field is captured with a temporal resolution of 250 ms for the horizontal and vertical central cross-section of the cube.

Ultrasound velocity measurements were performed in a liquid metal flow (GaInSn) inside a cubic vessel. The flow was driven by the combined action of a rotating (RMF) and a travelling magnetic field (TMF) leading to an inherent three-dimensional electromagnetic force distribution in the fluid. As a result flow structures develop which are essentially determined by the frequency difference and the strength relation of both fields. The driving force is stationary for identical frequencies whereas it undergoes a slow temporal modulation in case of slightly varying frequencies. Beside the magnetic field parameter the alignment of the TMF’s to the fluid volume’s axis plays a crucial role. A novel ultrasound array system was used in the present study to measure two velocity components in two perpendicular planes (2d-2c) simultaneously. This contribution reports on the influence of axial alignment on the flow, and on the flow dynamics resulting from slightly different field frequencies of the RMF and the TMF.

Investigating the complex interaction of conductive fluids and magnetic fields is relevant for a variety of applications from basic research in magnetohydrodynamics (MHD) to modeling industrial processes involving metal melts, such as the crystal growth process in the photovoltaic industry. This enables targeted optimizations of the melt flow and allows to significantly increase the yield and energy efficiency of an industrial process. However, experimental studies in this field are often limited by the performance of flow instrumentation for opaque liquids. We present an ultrasound array Doppler velocimeter (UADV) for flow mapping in opaque liquids at room temperature. It is modular and flexible regarding its measurement configuration, for instance it allows capturing two velocity components in two planes (2d-2c). It uses up to 9 linear arrays with a total element count of 225, driven in a parallelized time division multiplex (TDM) scheme. A FPGA-based signal pre-processing allows to handle the massive data bandwidth of typ. 1.2 GB/s and enables a continuous and near-realtime operation of the measurement system. Combining the velocity information of multiple arrays necessitates precise knowledge of their relative geometric position. We present a novel method for spatial self-calibration by a mutual time of flight measurement that significantly reduces the alignment errors. The capabilities of the UADV system are demonstrated in an experiment for basic MHD research. A cubic plexiglas container (67mm3) is filled with a metal melt (GaInSn, melting point 10°C). The flow induced by time-varying rotating magnetic fields is captured with a temporal resolution of 250ms and an uncertainty of approx. 1% for the horizontal and vertical central cross-section of the cube (2d- 2c).

Investigating the complex interaction of conductive fluids and magnetic fields is relevant for a variety of applications from basic research in magnetohydrodynamics (MHD) to modeling industrial processes involving metal melts, such as the crystal growth process in the photovoltaic industry. This enables targeted optimizations of the melt flow and allows to significantly increase the yield and energy effciency of industrial processes. However, experimental studies in this field are often limited by the performance of flow instrumentation for opaque liquids. We present an ultrasound array Doppler velocimeter (UADV) for flow mapping in opaque liquids at room temperature. It is modular and flexible regarding its measurement configuration, for instance it allows capturing two velocity components in two planes (2d - 2c). It uses up to 9 linear arrays with a total element count of 225, driven in a parallelized time division multiplex (TDM) scheme. A FPGA-based signal pre-processing allows to handle the massive data bandwidth of typ. 1.2 GB/s and enables a continuous and near-realtime operation of the measurement system. The capabilities of the UADV system are demonstrated in a basic MHD research experiment with a metal melt (GaInSn) in a cubic container of (67 mm)³. The flow induced by a rotating magnetic field is captured with a temporal resolution of 250 ms for the horizontal and vertical central cross-section of the cube.

Ultrasound velocity measurements were performed in a liquid metal flow (GaInSn) inside a cubic vessel. The flow was driven by the combined action of a rotating (RMF) and a travelling magnetic field (TMF) leading to an inherent three-dimensional electromagnetic force distribution in the fluid. As a result flow structures develop which are essentially determined by the frequency difference and the strength relation of both fields. The driving force is stationary for identical frequencies whereas it undergoes a slow temporal modulation in case of slightly varying frequencies. Beside the magnetic field parameter the alignment of the TMF’s to the fluid volume’s axis plays a crucial role. A novel ultrasound array system was used in the present study to measure two velocity components in two perpendicular planes (2d-2c) simultaneously. This contribution reports on the influence of axial alignment on the flow, and on the flow dynamics resulting from slightly different field frequencies of the RMF and the TMF.

Einleitung: Penetrierende Halsverletzungen können innerhalb kürzester Zeit zu lebensbedrohlichen Situationen führen und stellen aufgrund der komplexen Anatomie, der Nähe vitaler Strukturen und der Gefahr der akuten Verlegung der Atemwege eine Herausforderung in der Notfallmedizin dar. Ziel der Studie war die retrospektive Analyse von Patienten mit diesem Verletzungsmuster zur Optimierung des klinischen Managements in Diagnostik und Therapie. Methoden: In die Studie wurden insgesamt 35 Patienten mit Halsstich- und Halsschnittverletzungen eingeschlossen, die von 2001-2009 in unserer Klinik behandelt wurden. Ausgewertet wurden Daten zum Unfallhergang, Verletzungsmuster und zur durchgeführten Diagnostik und Therapie.Ergebnisse: Mit 65,7% waren v.a. männliche Patienten betroffen (m/w: 12/ 23). Die Altersspanne reichte vom 19.-80. Lebensjahr (MW 40,4 a). In der Mehrheit handelte es sich um Rohheitsdelikte (n=22), gefolgt von Suizidversuchen (n=9) und Unfällen (n=4). Bei allen Patienten erfolgte umgehend eine Wundexploration in ITN, wobei überwiegend Weichteilverletzungen der Zone II (n= 29) versorgt wurden. Folgende anatomische Strukturen waren zusätzlich betroffen: Gl. submandibularis (n=2); A. carotis (n=3), V. jugularis interna (n=2), Kehlkopf- u. Trachealverletzungen (n=6). Zusätzlich erfolgte eine Panendoskopie, sechs Patienten wurden tracheostomiert. Zwei Patienten erlagen ihren Verletzungen beide u.a. mit Verletzungen der A. carotis communis.Schlussfolgerung: Um Halsstich- und -schnittverletzungen adäquat zu behandeln u. schwerwiegende, möglicherweise tödlich verlaufende Verletzungen zu erkennen, sind fundierte anatomische Kenntnisse, schnelles Handeln u. gezielte diagnostische Methoden basierend auf einem klar definiertem Management gefordert.