Multi-frequency electrical impedance tomography of the breast: new clinical results

Electrical impedance tomography (EIT) has been used in the recent past for a number of clinical applications. In this work we present recent tomographic and spectroscopic findings for breast imaging from clinical exams completed at Dartmouth. The results presented here are based on 18 normal and 24 abnormal subjects. The participants were classified as normal or abnormal using the American College of Radiology (ACR) indexing system for mammograms. The EIT data were collected for ten discrete frequencies in the range 10 kHz-1 MHz using a single array of 16 electrodes. The finite element method was used to reconstruct the images. The images were examined visually and were compared with mammograms. The results were also analyzed based on zonal averages of property values and breast tissue radiodensities. Statistical analysis showed a significance difference between the mean conductivity and permittivity values of normal and abnormal subjects for various zones defined on the reconstructed images. Tissues with high radiodensity also had increased conductivity and permittivity.

[1]  Hamid Dehghani,et al.  A novel data calibration scheme for electrical impedance tomography. , 2003, Physiological measurement.

[2]  David Isaacson,et al.  NOSER: An algorithm for solving the inverse conductivity problem , 1990, Int. J. Imaging Syst. Technol..

[3]  T P Ryan,et al.  Temperature field estimation using electrical impedance profiling methods. I. Reconstruction algorithm and simulated results. , 1994, International journal of hyperthermia : the official journal of European Society for Hyperthermic Oncology, North American Hyperthermia Group.

[4]  D. S. Holder,et al.  Electrical impedance tomography (EIT) of brain function , 2005, Brain Topography.

[5]  Keith D Paulsen,et al.  Imaging the breast with EIS: an initial study of exam consistency. , 2002, Physiological measurement.

[6]  Brian H. Brown,et al.  Medical impedance tomography and process impedance tomography: a brief review , 2001 .

[7]  J C Newell,et al.  Reconstruction of conductivity changes due to ventilation and perfusion from EIT data collected on a rectangular electrode array. , 2001, Physiological measurement.

[8]  A Korjenevsky,et al.  Preliminary static EIT images of the thorax in health and disease. , 2002, Physiological measurement.

[9]  Keith D. Paulsen,et al.  A multichannel continuously selectable multifrequency electrical impedance spectroscopy measurement system , 2000, IEEE Transactions on Biomedical Engineering.

[10]  David Isaacson,et al.  Electrical Impedance Tomography , 1999, SIAM Rev..

[11]  J Jossinet,et al.  Tissue impedance: a historical overview. , 1995, Physiological measurement.

[12]  Keith D. Paulsen,et al.  Electrical impedance spectroscopy of the breast: clinical imaging results in 26 subjects , 2002, IEEE Transactions on Medical Imaging.

[13]  A Korjenevsky,et al.  A 3D electrical impedance tomography (EIT) system for breast cancer detection. , 2001, Physiological measurement.

[14]  A Hartov,et al.  Multifrequency electrical impedance imaging: preliminary in vivo experience in breast. , 2000, Physiological measurement.

[15]  W R Breckon,et al.  Mathematical aspects of impedance imaging. , 1987, Clinical physics and physiological measurement : an official journal of the Hospital Physicists' Association, Deutsche Gesellschaft fur Medizinische Physik and the European Federation of Organisations for Medical Physics.

[16]  K D Paulsen,et al.  An enhanced electrical impedance imaging algorithm for hyperthermia applications. , 1997, International journal of hyperthermia : the official journal of European Society for Hyperthermic Oncology, North American Hyperthermia Group.