Design and calibration of a compact multi-frequency EIT system for acute stroke imaging

Physiol Meas. 2006 May;27(5):S199-210. doi: 10.1088/0967-3334/27/5/S17. Epub 2006 Apr 24.

Abstract

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.

Publication types

  • Clinical Trial
  • Research Support, Non-U.S. Gov't
  • Validation Study

MeSH terms

  • Acute Disease
  • Algorithms*
  • Calibration
  • Computer Simulation
  • Electric Impedance*
  • Equipment Design
  • Equipment Failure Analysis
  • Humans
  • Image Enhancement / instrumentation*
  • Image Enhancement / methods
  • Image Enhancement / standards
  • Image Interpretation, Computer-Assisted / methods
  • Image Interpretation, Computer-Assisted / standards
  • Miniaturization
  • Models, Neurological
  • Phantoms, Imaging
  • Plethysmography, Impedance / instrumentation*
  • Plethysmography, Impedance / methods
  • Plethysmography, Impedance / standards
  • Reproducibility of Results
  • Sensitivity and Specificity
  • Stroke / diagnosis*
  • Stroke / physiopathology*
  • Tomography / instrumentation*
  • Tomography / methods
  • Tomography / standards