Patent · US Expired

Process and apparatus for distinguishing conductivities by electric current computed tomography

US4920490A · kind A · utility

76Cited by
5References
3Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJan 28, 1988
Grant dateApr 24, 1990
Priority date
Expiry dateJan 28, 2008

Classification

  • Technology area (CPC A)Human Necessities
  • CPC primaryA61B5/0536
  • WIPO fieldMedical technology
  • WIPO sectorInstruments

Abstract

A method and apparatus for an electric current computed tomography system having an array of electrodes determines the best pattern of currents to apply to the electrodes based on the precision of the system for distinguishing between a known conductivity in a body and an unknown conductivity. An arbitrary current pattern is first applied to the array, which is at the surface of the body. Measurements are then taken for the resulting voltage pattern of the unknown conductivity. Calculations are then made to determine the calculated voltage pattern for the selected conductivity. The absolute value of the difference between the calculated and measured voltage patterns are then taken and, from this, a new current pattern is calculated. If the difference between the new current pattern and the arbitrary current pattern is less than the precision of the system, the arbitrary current pattern is applied to the electrodes. More likely, however, the difference will be greater than the precision. In this case, the new current pattern is applied to the electrodes and the measurements and calculations are repeated to generate a still further new current pattern. The difference between the prev…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.