Title :
A parallel data acquisition system for electrical impedance tomography
Author :
Rosell, Javier ; Riu, Pere ; Pallas-areny, Ramon
Author_Institution :
Div. de Instrum. y Bioingenieria, ETS Ing Telecom, Barcelona, Spain
Abstract :
A PC-based parallel data acquisition system designed for electrical impedance tomography and a test method for evaluating its performance are described. The system uses 16 electrodes and 16 differential channels to acquire up to 10 images/s. A single programmable-frequency current source is connected to any pair of electrodes by a multiplexer. Image reconstruction is based on a weighted backprojection and takes about 1 s. The common mode rejection ratio, the use of feedback to increase it, and channel crosstalk are analyzed. Acquisition errors are evaluated from dependent measurements and the reciprocity theorem. Some preliminary results obtained by applying this system to the acquisition of thoracic images related to cardiac activity are presented. Final images are obtained by averaging between 20 and 100 cardiac-gated cycles
Keywords :
bioelectric phenomena; biomedical equipment; computerised tomography; data acquisition; medical diagnostic computing; microcomputer applications; 1 s; PC-based parallel data acquisition system; acquisition errors; cardiac activity; cardiac-gated cycles; channel crosstalk; differential channels; electrical impedance tomography; electrodes; image reconstruction; medical diagnostic imaging; multiplexer; programmable-frequency current source; reciprocity theorem; thoracic images; weighted backprojection; Crosstalk; Data acquisition; Electrodes; Feedback; Image reconstruction; Imaging phantoms; Impedance measurement; System testing; Tomography; Voltage;
Conference_Titel :
Engineering in Medicine and Biology Society, 1989. Images of the Twenty-First Century., Proceedings of the Annual International Conference of the IEEE Engineering in
Conference_Location :
Seattle, WA
DOI :
10.1109/IEMBS.1989.95818
