Cardiac mapping of electrical impedance tomography by means of a wavelet model

Harki Tanaka^1*, Neli Regina Siqueira Ortega², Andre Hovnanian³, Carlos Roberto Ribeiro de Carvalho³, Marcelo Britto Passos Amato³

¹Center of Engineering, Modelling and Applied Social Sciences, Federal University of ABC, Sao Paulo, Brazil.
²Center of Fuzzy Systems in Health, School of Medicine, University of Sao Paulo, Sao Paulo, Brazil.
³Respiratory Intensive Care Unit, Hospital das Clínicas, School of Medicine, University of Sao Paulo, Sao Paulo, Brazil.

DOI: 10.4236/wjcd.2013.37073                

Abstract

To improve the identification of cardiac regions in Electrical impedance tomography (EIT) pulmonary perfusion images, a model of wavelet transform was developed. The main goal was to generate maps of the heart using EIT images in a controlled animal experiment using a healthy pig and in two human volunteers. The model was capable of identifying the heart regions, demonstrated robustness and generated satisfactory results. The pig images were compared to perfusion images obtained using injection of a hypertonic solution and achieved an average area of the ROC curve of 0.88. The human images were qualitatively compared with Computerized Tomography scan (CT-scan) images.

Keywords

Electrical Impedance Tomography; Heart; Image Analysis; Image Segmentation; Wavelet

Conflicts of Interest

The authors declare no conflicts of interest.

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