Article
Refine
Year of publication
Institute
- Fachbereich Elektrotechnik und Informationstechnik (638) (remove)
Document Type
- Article (638) (remove)
Keywords
- Multimediamarkt (6)
- Hot S-parameter (2)
- Literaturanalyse (2)
- MINLP (2)
- Referenzmodellierung (2)
- 197m/gHg (1)
- 3-D printing (1)
- Anwendungsorientierter Forschungsansatz (1)
- Arbeit 4.0 (1)
- Automated driving (1)
- Automotive application (1)
- Benchmark (1)
- Bloom’s Taxonomy (1)
- Booster Stations (1)
- Buffering Capacity (1)
- CAV (1)
- Cardiovascular Magnetic Resonance (1)
- Chance Constraint (1)
- Chaostheorie (1)
- Chatbots (1)
- Circuit simulation (1)
- Competence Developing Games (1)
- Content Management (1)
- Design Science Research (1)
- Digitalisierung (1)
- E-Learning (1)
- EBSCO Discovery Service (1)
- EGG (1)
- Engineering Application (1)
- Enhanced Telecom Operations Map (1)
- Experimental validation (1)
- Forschungsprozess (1)
- Furnace (1)
- Fusion (1)
- Game-based learning (1)
- Gold nanoparticle (AuNP) (1)
- High field MRI (1)
- IBM Watson Explorer (1)
- IP-based networks (1)
- IT security education (1)
- Image Quality Assessment (1)
- Image Quality Score (1)
- Interval Time Series (1)
- Keyword analysis (1)
- Larynx position (1)
- Li7La3Zr2O12 (1)
- LiGaO2 (1)
- Lidar (1)
- Literaturrecherche (1)
- MILP (1)
- MPEG 4 (1)
- MPEG 7 (1)
- MPEG-Standard (1)
- MR safety (1)
- MRI (1)
- Magneto alert sensor (1)
- Meitner-Auger-electron (MAE) (1)
- Mode converter (1)
- Modeling (1)
- Multimedia-Dienst (1)
- NGN (1)
- Plasma (1)
- Plasma diagnostics (1)
- Powertrain (1)
- Praxisprojekte (1)
- Process virtualization (1)
- Product bundling (1)
- Prozessabläufe (1)
- Prozessautomatisierung (1)
- Prozessmodellierung (1)
- Prozessstandardisierung (1)
- Pump System (1)
- Pumping systems (1)
- Radar (1)
- Robotic Process Automation (1)
- Rotary encoder (1)
- Self-driving (1)
- Services (1)
- Sound Pressure Level (1)
- Stochastic Programming (1)
- Targeted radionuclide therapy (TRT) (1)
- Technical Operations Research (1)
- Telecommunication (1)
- Text Analytics (1)
- Text Analytics (1)
- Text Mining (1)
- Tomography (1)
- Transfer impedance (1)
- Transformation (1)
- Uktrahigh field MRI (1)
- Uncertainty (1)
- VOP compression (1)
- Voice assessment (1)
- Water Distribution (1)
- Water Supply Networks (1)
- Wiegand sensor (1)
- automated vehicles (1)
- availability (1)
- batteries and fuel cells (1)
- body imaging at 7 T MRI (1)
- body imaging at UHF MRI (1)
- connected automated vehicles (1)
- design of technical systems (1)
- eTOM (1)
- electrospinning (1)
- energy efficiency (1)
- energy transfer (1)
- experimental evaluation (1)
- fibers (1)
- ga-doping (1)
- garnet solid electrolyte (1)
- genetic algorithm (1)
- global optimization (1)
- harmonic radar (1)
- harmonic radar tags (1)
- heating system (1)
- ignition (1)
- integrated transmit coil arrays (1)
- irradiation (1)
- legal obligations (1)
- mathematical optimization (1)
- microplasma (1)
- microwave (MW) plasma (1)
- microwave measurements (1)
- mixed-integer linear programming (1)
- next generation network (1)
- nonlinear VNA measurements (1)
- optimization (1)
- plasma jet (1)
- porous materials (1)
- product bundling (1)
- product liability (1)
- programming (1)
- remote sensing (1)
- resilience (1)
- slum classification (1)
- solid-state battery (1)
- stochastic optimization (1)
- sustainability (1)
- system optimization (1)
- system synthesis (1)
- technical operations research (1)
- telecommunication (1)
- thermal dose (1)
- tissue temperature (1)
- transmit antenna arrays (1)
- water supply design (1)
The simultaneous assessment of glottal dynamics and larynx position can be beneficial for the diagnosis of disordered voice or speech production and swallowing. Up to now, methods either concentrate on assessment of the glottis opening using optical, acoustical or electrical (electroglottography, EGG) methods, or on visualisation of the larynx position using ultrasound, computer tomography or magnetic resonance imaging techniques.
The method presented here makes use of a time-multiplex measurement approach of space-resolved transfer impedances through the larynx. The fast sequence of measurements allows a quasi simultaneous assessment of both larynx position and EGG signal using up to 32 transmit–receive signal paths. The system assesses the dynamic opening status of the glottis as well as the vertical and back/forward motion of the larynx.
Two electrode-arrays are used for the measurement of the electrical transfer impedance through the neck in different directions. From the acquired data the global and individual conductivity is calculated as well as a 2D point spatial representation of the minimum impedance.
The position information is shown together with classical EGG signals allowing a synchronous visual assessment of glottal area and larynx position. A first application to singing voice analysis is presented that indicate a high potential of the method for use as a non-invasive tool in the diagnosis of voice, speech, and swallowing disorders.
Objective:
To develop a transmit/receive radiofrequency (RF) array for magnetic resonance imaging (MRI) of the carotid arteries at 7 T. The prototype is characterized in numerical simulations and bench measurements, and the feasibility of plaque imaging at 7 T is demonstrated in first in vivo images.
Materials and Methods:
The RF phased array coil consists of 8 surface loop coils. To allow imaging of both sides of the neck, the RF array is divided into 2 coil clusters, each with 4 overlapping loop elements. For safety validation, numerical computations of the RF field distribution and the corresponding specific absorption rate were performed on the basis of a heterogeneous human body model. To validate the coil model, maps of the transmit B1+ field were compared between simulation and measurement. In vivo images of a healthy volunteer and a patient (ulcerating plaque and a 50% stenosis of the right internal carotid artery) were acquired using a 3-dimensional FLASH sequence with a high isotropic spatial resolution of 0.54 mm as well as using pulse-triggered proton density (PD)/T2-weighted turbo spin echo sequences.
Results:
Measurements of the S-parameters yielded a reflection and isolation of the coil elements of better than −18 and −13 dB, respectively. Measurements of the g-factor indicated good image quality for parallel imaging acceleration factors up to 2.4. A similar distribution and a very good match of the absolute values were found between the measured and simulated B1+ transmit RF field for the validation of the coil model. In vivo images revealed good signal excitation of both sides of the neck and a high vessel-to-background image contrast for the noncontrast-enhanced 3-dimensional FLASH sequence. Imaging at 7 T could depict the extent of stenosis, and revealed the disruption and ulcer of the plaque.
Conclusions:
This study demonstrates that 2 four-channel transmit/receive RF arrays for each side of the neck is a suitable concept for in vivo MRI of the carotid arteries at 7 Tesla. Further studies are needed to explore and exploit the full potential of 7 T high-field MRI for carotid atherosclerotic plaque imaging.
Absatzkanäle kaum verknüpft
(2011)