EIT is a imaging method based on measurement of voltages and currents on the surface of some object.
What is EIT?
- Different tissues have a different electrical conductivity
- Applying currents and measuring voltages using electrodes on the body surface
- Creating an image of the impedance/admittivity distribution inside the body
The model we used
- Thorax with lungs: Model consisted of7680 elements –Matrix includes≈6∙107 elements
Admittance gradient – TISSUES
noise
- Noise of course is present in every electrical system.
- But we want to check what level of noise will enable a tolerable reconstruction.
- We added noise ~ N(0,a) to the voltage read of each electrode
Reconstruction time
- A full reconstruction took ~10 seconds
- That is good for some purposes (tumor detection, etc’) but not for a real-time system
- Our system is not well suited for this job, and matlab is very inefficient
- Perhaps with lower settings, algorithm tweaks or a special system, the time will be much shorter
Conclusions
- More electrodes are not necessarily better
- Admittance gradient will always increase the error but not always the same way
- We found what levels of noise are tolerable
- Our current system is not ready for real-time activity