A new, compact UCLH Mk 2.5 EIT system has been developed and calibrated for EIT imaging of the head. Improvements include increased input and output impedances, increased bandwidth and improved CMRR (80 dB) and linearity over frequencies and load (0.2% on a single channel, +/-0.7% on a saline tank over 20 Hz-256 kHz and 10-65 Omega). The accuracy of the system is sufficient to image severe acute stroke according to the specification from recent detailed anatomical modelling (Horesh et al 2005 3rd European Medical and Biological Engineering Conference EMBEC'05). A preliminary human study has validated the main specifications of the modelling, the range of trans-impedance from the head (8-70 Omega) using a 32 electrode, 258 combination protocol and contact impedances of 300 Omega to 2.7 kOmega over 20 Hz to 256 kHz.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1088/0967-3334/27/5/S17 | DOI Listing |
Intensive Crit Care Nurs
January 2025
Department of Intensive Care Medicine, Hospital Universitario de La Princesa, Madrid, Spain; Centro de investigación en red CIBERES de enfermedades respiratorias, Instituto de Salud, Carlos III, Madrid, Spain. Electronic address:
Objectives: To analyse the effects on respiratory function, lung volume and the regional distribution of ventilation and perfusion of routine postural repositioning in mechanically ventilated critically ill patients.
Methods: Prospective descriptive physiological study. We evaluated gas-exchange, lung mechanics, and Electrical Impedance Tomography (EIT) determined end-expiratory lung impedance and regional ventilation and perfusion distribution in five body positions: supine-baseline (S1); first lateralisation at 30° (L1); second supine position (S2), second contralateral lateralisation (L2) and third final supine position (S3).
Materials (Basel)
January 2025
Institute of Physical Chemistry, Bulgarian Academy of Sciences, Acad. G. Bonchev St., Bl.11, 1113 Sofia, Bulgaria.
Calcium phosphates are often used for biomedical applications. Hydroxyapatite, for example, has a wide range of applications because it mimics the mineral component of natural bone. Widespread interest in the catalytic properties of ceria is due to its use in automotive catalytic converters.
View Article and Find Full Text PDFFluids Barriers CNS
January 2025
Department of Biomedical Engineering, Air Force Medical University, Xi'an, China.
Background: Acute and critical neurological diseases are often accompanied with elevated intracranial pressure (ICP), leading to insufficient cerebral perfusion, which may cause severe secondary lesion. Existing ICP monitoring techniques often fail to effectively meet the demand for real-time noninvasive ICP monitoring and warning. This study aimed to explore the use of electrical impedance tomography (EIT) to provide real-time early warning of elevated ICP by observing cerebral perfusion.
View Article and Find Full Text PDFACS Photonics
January 2025
Institute of Electronic Structure and Laser, Foundation for Research and Technology-Hellas (FORTH-IESL), GR-70013 Heraklion, Crete, Greece.
THz metamaterials present unique opportunities for next-generation technologies and applications as they can fill the "THz gap" originating from the weak response of natural materials in this regime, providing a variety of novel or advanced electromagnetic wave control components and systems. Here, we propose a novel metamaterial design made of three-dimensional, metallic, "cactus-like" meta-atoms, showing electromagnetically induced transparency (EIT) and enhanced refractive index sensing performance at low THz frequencies. Following a detailed theoretical analysis, the structure is realized experimentally using multiphoton polymerization and electroless silver plating.
View Article and Find Full Text PDFInt J Numer Method Biomed Eng
January 2025
Bioengineering, Department of Electrical, Electronic and Computer Engineering, University of Pretoria, Gauteng, South Africa.
The imaging of the live cochlea is a challenging task. Regardless of the quality of images obtained from modern clinical imaging techniques, the internal structures of the cochlea mainly remain obscured. Electrical impedance tomography (EIT) is a safe, low-cost alternative medical imaging technique with applications in various clinical scenarios.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!