PVCP-based anthropomorphic breast phantoms containing structures similar to lactiferous ducts for ultrasound imaging: A comparison with human breasts.

The purpose of this work was to obtain an anthropomorphic phantom with acoustic properties similar to those of breast tissue, possessing lactiferous duct-like structures, which would be a first for this type of phantom. Breast lesions usually grow in glandular tissues or lactiferous ducts. Shape variations in these structures are detectable by using ultrasound imaging. To increase early diagnosis, it is important to develop computer-aided diagnosis (CAD) systems and improve medical training. Using tissue-like materials that mimic known internal structures can help achieve both of these goals. However, most breast ultrasound phantoms described in the literature emulate only fat tissues and lesion-like masses. In addition, commercially available phantoms claim to be realistic, but do not contain lactiferous duct structures. In this work, we collected reference images from both breasts of ten healthy female volunteers aged between 20 and 30 years using a 10 MHz linear transducer of a B-mode medical ultrasound system. Histograms of the grey scale distribution of each tissue component of interest, the grey level means, and standard deviations of the regions of interest were obtained. Phantoms were produced using polyvinyl chloride plastisol (PVCP) suspensions. The lactiferous duct-like structures were prepared using pure PVCP. Solid scatterers, such as alumina (mesh #100) and graphite powders (mesh #140) were added to the phantom matrix to mimic glandular and fat tissue, respectively. The phantom duct-like structure diameters observed on B-mode images (1.92 mm ± 0.44) were similar to real measures obtained with a micrometer (2.08 mm ± 0.23). The phantom ducts are easy to produce and are largely stable for at least one year. This phantom allows the researchers to elaborate the structure at their will and may be used in training and as a reference for development of CAD systems.