Title :
ACT3: a high-speed, high-precision electrical impedance tomograph
Author :
Cook, Raymond D. ; Saulnier, Gary J. ; Gisser, David G. ; Goble, John C. ; Newell, J.C. ; Isaacson, David
Author_Institution :
Dept. of Biomed. Eng., Rensselaer Polytech. Inst., Troy, NY, USA
Abstract :
Presents the design, implementation, and performance of Rensselaer´s third-generation adaptive current tomograph, ACT3. This system uses 32 current sources and 32 phase-sensitive voltmeters to make a 32-electrode system that is capable of applying arbitrary spatial patterns of current. The instrumentation provides 16 b precision on both the current values and the real and reactive voltage readings and can collect the data for a single image in 133 ms. Additionally, the instrument is able to automatically calibrate its voltmeters and current sources and adjust the current source output impedance under computer control. The major system components are discussed in detail and performance results are given. Images obtained using stationary agar targets and a moving pendulum in a phantom as well as in vivo resistivity profiles showing human respiration are shown.
Keywords :
biomedical equipment; computerised tomography; electric impedance imaging; 133 ms; 16 b precision; 32-electrode system; arbitrary current spatial patterns; automatic calibration; high-speed high-precision electrical impedance tomograph; human respiration; in vivo resistivity profiles; medical diagnostic imaging; moving pendulum; phantom; reactive voltage readings; stationary agar targets; Automatic control; Biomedical computing; Biomedical engineering; Current; Electrodes; Frequency estimation; Instruments; Surface impedance; Voltage; Voltmeters; Algorithms; Calibration; Computers, Analog; Electric Impedance; Electronics; Equipment Design; Humans; Image Processing, Computer-Assisted; Models, Structural; Respiration; Signal Processing, Computer-Assisted; Tomography;
Journal_Title :
Biomedical Engineering, IEEE Transactions on
