Title :
EBCT imaging of heart and lungs triggered by ECG and ventilation
Author :
Hutten, Helmut ; Mitterbacher, André
Author_Institution :
Inst. of Biomed. Eng., Graz Univ. of Technol., Austria
Abstract :
A device has been developed to monitor both the bioimpedance across the thorax using the four-electrode method and the ECG. The transthoracic bioimpedance signal depends on the alveolar air volume. Coincidence of the ECG related trigger signal (e.g. R-wave) with a set tolerance band for this bioimpedance signal is determined and employed to trigger the electron beam computerised tomography (EBCT) imaging. The coincidence rate of the R-wave with the alveolar air volume depends on the width of the tolerance band. Furthermore, the coincidence rate depends on the position of the tolerance band between the endinspiratory and the endexpiratory volume. When the tolerance band is set to 10% of the tidal volume (approx. 50 ml) the displacement effect is estimated to be about 2 mm. Under these conditions, the total cycle time is prolonged to about 200 s. The trigger device has been successfully used to control the EBCT machine
Keywords :
computerised tomography; electrocardiography; electron beam applications; pneumodynamics; 200 s; ECG; R-wave; alveolar air volume; bioimpedance across thorax; coincidence rate; electron beam computerised tomography imaging; four-electrode method; heart; medical diagnostic imaging; set tolerance band; transthoracic bioimpedance signal; ventilation; Bioimpedance; Blood; Electrocardiography; Filling; Heart; Impedance; Lungs; Patient monitoring; Thorax; Ventilation;
Conference_Titel :
Engineering in Medicine and Biology Society, 2000. Proceedings of the 22nd Annual International Conference of the IEEE
Conference_Location :
Chicago, IL
Print_ISBN :
0-7803-6465-1
DOI :
10.1109/IEMBS.2000.900824