| Автор | Tian-Xian Zhao |
| Автор | Brian H Brown |
| Автор | Peter Nopp |
| Автор | Wei Wang |
| Автор | Andrew D Leathard |
| Автор | Li-Qin Lu |
| Дата выпуска | 1996-11-01 |
| dc.description | Resistivity data from 9.6 kHz to 1.2 MHz were recorded from eight normal subjects using an electrical impedance tomographic spectroscopy (EITS) system and then averaged to a mean cardiac cycle using the ECG gating technique. The Cole - Cole model, that is, extracellular resistance R connected in parallel with intracellular resistance S and membrane capacitance C in series, with a distribution parameter a, was applied to model the frequency characteristics and to produce parametric images. During systole, SC and RC were found to decrease and FR increase. The changes in R/S were not consistent among the subjects. We estimated the peak changes in R, S and C to be -2.5%, -3.3% and -7.6% respectively. The results can be explained by considering the blood vessels as spheres of different sizes with blood inside them. The decrease in R during systole might be caused by the increased blood content in relatively large vessels, whereas that in S by the increased blood volume in relatively small vessels. The capacitance of blood is normally smaller than that of lung tissue, whereas FR of blood is higher than that of lung tissue. Hence, as blood content increases, C should decrease and FR increase. |
| Формат | application.pdf |
| Издатель | Institute of Physics Publishing |
| Название | Modelling of cardiac-related changes in lung resistivity measured with EITS |
| Тип | paper |
| DOI | 10.1088/0967-3334/17/4A/027 |
| Electronic ISSN | 1361-6579 |
| Print ISSN | 0967-3334 |
| Журнал | Physiological Measurement |
| Том | 17 |
| Первая страница | A227 |
| Последняя страница | A234 |
| Аффилиация | Tian-Xian Zhao; Department of Medical Physics and Clinical Engineering, The University of Sheffield, Royal Hallamshire Hospital, Glossop Road, Sheffield S10 2JF, UK |
| Аффилиация | Brian H Brown; Department of Medical Physics and Clinical Engineering, The University of Sheffield, Royal Hallamshire Hospital, Glossop Road, Sheffield S10 2JF, UK |
| Аффилиация | Peter Nopp; Department of Medical Physics and Clinical Engineering, The University of Sheffield, Royal Hallamshire Hospital, Glossop Road, Sheffield S10 2JF, UK |
| Аффилиация | Wei Wang; Department of Medical Physics and Clinical Engineering, The University of Sheffield, Royal Hallamshire Hospital, Glossop Road, Sheffield S10 2JF, UK |
| Аффилиация | Andrew D Leathard; Department of Medical Physics and Clinical Engineering, The University of Sheffield, Royal Hallamshire Hospital, Glossop Road, Sheffield S10 2JF, UK |
| Аффилиация | Li-Qin Lu; Department of Medical Physics and Clinical Engineering, The University of Sheffield, Royal Hallamshire Hospital, Glossop Road, Sheffield S10 2JF, UK |
| Выпуск | 4A |
