Title :
Using deconvolved dispersion parameters for selecting EIT frequencies
Author :
McRae, Donald A. ; Esrick, Mark A.
Author_Institution :
Dept. of Radiat. Med., Georgetown Univ., Washington, DC, USA
Abstract :
The electrical impedance from 100 Hz to 40 MHz was measured for two types of human tumor xenografts. The measurements were made non-invasively, in vivo during hyperthermia treatments. Each impedance spectrum was fit using the sum of two Cole-Cole dispersions. The conductivity at the relaxation frequency (Fc) of each dispersion (σFc), and the conductivity at 10 MHz (σ10M) were selected for subsequent use. Using the σ-ratios σ10M/σFc temperature-dependent effects were minimized and two different aspects of the cellular damage sequence were able to be followed during the hyperthermia treatments. Using each σ and its temperature coefficient, the temperature changes can be simultaneously estimated in the usual way
Keywords :
cellular biophysics; deconvolution; electric impedance imaging; hyperthermia; σ-ratios; 100 Hz to 40 MHz; Cole-Cole dispersions; EIT frequencies; cellular damage sequence; conductivity; deconvolved dispersion parameters; dispersion; electrical impedance; electrical impedance tomography; human tumor xenografts; hyperthermia treatments; impedance spectrum; in vivo; noninvasive measurement; relaxation frequency; temperature changes; temperature coefficient; temperature-dependent effects; Colon; Conductivity; Frequency; Humans; Hyperthermia; Impedance measurement; In vivo; Mice; Neoplasms; Temperature measurement;
Conference_Titel :
Bioengineering Conference, 1996., Proceedings of the 1996 IEEE Twenty-Second Annual Northeast
Conference_Location :
New Brunswick, NJ
Print_ISBN :
0-7803-3204-0
DOI :
10.1109/NEBC.1996.503224
