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The research here presented aims at developing a new, promising method for the imaging diagnostics of breast lesions - ultrasound tomography (UST). A currently implemented device enables the reconstruction three complementary images for each coronal breast section. Based on in vivo breast examination, the authors developed an approach to breast diagnostics which employs ultrasound transmission and reflection tomography imaging. The obtained transmission images of ultrasound speed distribution show good correlation of glandular tissue areas with their visualization on MRI images. The results also allow a prediction that the implemented UST device offering fusion of reconstructed images may contribute to achieving a new standard for breast cancer diagnostics through non-invasive, fast and cheap screening tests.

The paper presents the preliminary results of examinations of biological structures and healthy breast tissue in vivo obtained with the developed ultrasound tomography model. This device uses an innovative combination of ultrasound transmission tomography (UTT) and ultrasound reflection tomography (URT) which enable to obtain three-dimensional images in the same way as in the classical computer tomography (CT). The huge advantage of these methods is not exposing the patient to ionizing radiation. Compared to conventional breast ultrasonic echography (US), UTT and URT methods enable to acquire a much larger amount of information whose clinical significance has not been well documented yet. Based on the preliminary results, it is anticipated that the ultrasound tomography may contribute to the creation of a new standard of diagnosis and treatment of breast cancer. Currently, a Polish manufacturer of ultrasound scanners aims at getting an ultrasonic tomography device for examining women’s breasts to market.

Various types of undesirable crosstalk can occur in ultrasonic arrays consisting of a number of elementary piezoelectric transducers. Crosstalk is a result of deficiency in electrical or mechanical isolation between the array's elements. It is a function of proximity between piezoelectric transducers of the array or between connections. Small piezoceramic transducers tightly located inside of a circle (cylinder or sphere in 3-D systems) are used for in vivo ultrasound tomography imaging of breast tissue. This means that correct switching of transducers makes it possible to quickly acquire tomographic transmission and reflection data. A problem with such arrangements is the occurrence of crosstalk, which introduces specific errors to measurement data. Transmission and reflection tomographic images reconstructed based on ultrasonic measurements with crosstalk are distorted in a characteristic way. This work analyses the effect of crosstalk in a circular transducer array on ultrasound transmission tomography - especially, when used for examination of breast tissue.