Multimodal Breast Phantoms for Microwave, Ultrasound, Mammography, Magnetic Resonance and Computed Tomography Imaging

Abstract

The aim of this work was to develop multimodal anthropomorphic breast phantoms suitable for evaluating the imaging performance of a recently-introduced Microwave Imaging (MWI) technique in comparison to the established diagnostic imaging modalities of Magnetic Resonance Imaging (MRI), Ultrasound (US), mammography and Computed Tomography (CT). MWI is an emerging technique with significant potential to supplement established imaging techniques to improve diagnostic confidence for breast cancer detection. To date, numerical simulations have been used to assess the different MWI scanning and image reconstruction algorithms in current use, while only a few clinical trials have been conducted. To bridge the gap between the numerical simulation environment and a more realistic diagnostic scenario, anthropomorphic phantoms which mimic breast tissues in terms of their heterogeneity, anatomy, morphology, and mechanical and dielectric characteristics, may be used. Key in this regard is achieving realism in the imaging appearance of the different healthy and pathologic tissue types for each of the modalities, taking into consideration the differing imaging and contrast mechanisms for each modality. Suitable phantoms can thus be used by radiologists to correlate image findings between the emerging MWI technique and the more familiar images generated by the conventional modalities. Two phantoms were developed in this study, representing difficult-to-image and easy-to-image patients: the former contained a complex boundary between the mammary fat and fibroglandular tissues, extracted from real patient MRI datasets, while the latter contained a simpler and less morphologically accurate interface. Both phantoms were otherwise identical, with tissue-mimicking materials (TMMs) developed to mimic skin, subcutaneous fat, fibroglandular tissue, tumor and pectoral muscle. The phantoms’ construction used non-toxic materials, and they were inexpensive and relatively easy to manufacture. Both phantoms were scanned using conventional modalities (MRI, US, mammography and CT) and a recently introduced MWI radar detection procedure called in-coherent Multiple Signal Classification (I-MUSIC). Clinically realistic artifact-free images of the anthropomorphic breast phantoms were obtained using the conventional imaging techniques as well as the emerging technique of MWI.

Incoherent Radar Imaging for Breast Cancer Detection and Experimental Validation against 3D Multimodal Breast Phantoms

“…As mentioned in the introduction, this paper can be regarded as a companion paper of [ 33 ]. In that paper, we mainly focused on the design, construction and characterization of the breast phantom; microwave imaging algorithms were not described at all.…”

“…Accordingly, before obtaining the image, data must be first processed in order to reduce the clutter due to the antenna’s internal reflection, the skin interface and other non-tumor breast tissues. To this end, we employed a hybrid clutter removal method [ 33 ].…”

“…In this contribution we will give a quick review of the incoherent methods and detail the clutter mitigation procedure that was used, but actually not described, in [ 33 ]. In particular, the achievable cancer detection is checked by using experimental data collected by employing the multi-modal breast phantom developed in [ 33 ].…”

“…In this contribution we will give a quick review of the incoherent methods and detail the clutter mitigation procedure that was used, but actually not described, in [ 33 ]. In particular, the achievable cancer detection is checked by using experimental data collected by employing the multi-modal breast phantom developed in [ 33 ]. Accordingly, this paper focuses more on the image process and can be considered as a companion paper of [ 33 ] which, instead, mainly considered the development of the breast phantom and its tissue characterization for different imaging modalities.…”

Thermal Characterization of Phantoms Used for Quality Assurance of Deep Hyperthermia Systems

“…Tissue mimicking models (phantoms) have been proposed and are increasingly being adopted in the design, optimization and quality assurance of medical devices to guarantee their correct performance in clinical applications. In particular, multi-modal phantoms have been developed and are used in electromagnetic-based hyperthermia applications, such as deep or superficial hyperthermia and thermal ablation [1][2][3][4][5][6][7][8]. Such phantoms are required to mimic the target portion of human body of interest from an electromagnetic perspective, but also from a thermal point of view.…”