Limitations to SV determination from APT images

Date

1989-11-01

Author

Eyüboğlu, Behçet Murat
Barber, David

Metadata

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The limitations related to the position-dependent point response function (PRF) of an applied potential tomography (APT) system are determined. The 3-D distribution of the PRF is measured. The thickness of the APT's field of view (slice) and the spatial resolution are determined from these measurements. The effects of these parameters on the reconstructed image are discussed. The results show that the sensitive slice thickness is not uniform across the image plane and that the PRF is strongly dependent on position. Therefore, the appearance of localized resistivity changes in the images is a function of their position relative to the electrodes in 3-D space. The same amount of stroke volume (SV) at different spatial locations is therefore reconstructed differently. Hence, an accurate calculation of an index of cardiac volumes is complicated, and calibration is needed. A uniform sensitivity distribution across the image plane would result in more reliable volume indices. The FWHM resolution is position dependent and is a function of the conductivity change, being poorest at the center of the field.

Subject Keywords

Conductivity, Electrodes, Conductors, Tomography, In vivo, Humans, Thorax, Impedance, Voltage, Image reconstruction

URI

https://hdl.handle.net/11511/87526

DOI

https://doi.org/10.1109/IEMBS.1989.95809

Conference Name

1989 Annual International Conf Of The IEEE Engineering In Medicine And Biology Soc : Images Of The Twenty-First Century

Collections

Department of Electrical and Electronics Engineering, Conference / Seminar

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Citation Formats

B. M. Eyüboğlu and D. Barber, “Limitations to SV determination from APT images,” Seattle, WA, USA, 1989, p. 442, Accessed: 00, 2021. [Online]. Available: https://hdl.handle.net/11511/87526.