A Multimodal Image Reconstruction Method Using Ultrasonic Waves and Electrical Resistance Tomography

In this paper, a new system that improves the image obtained by an array of ultrasonic sensors using electrical resistance tomography (ERT) is presented. One of its target applications can be in automatic exploration of soft tissues, where different organs and eventual anomalies exhibit simultaneously different electrical conductivities and different acoustic impedances. The exclusive usage of the ERT technique usually leads to some significant uncertainties around the regions´ boundaries and usually generates images with relatively low resolutions. The proposed method shows that by properly combining this technique with an ultrasonic-based method, which can provide good localization of some edge points, the accuracy of the shape of individual cells can be improved, if these edge points are used as constraints during the inversion procedure. The performance of the proposed reconstruction method was assessed by conducting extensive tests on some simulated phantoms which mimic soft tissues. The obtained results clearly show the outperformance of this method over single modalities techniques that use either ultrasound or ERT imaging.