Microwave radiometry is a passive imaging modality proposed for breast cancer detection without the need for ionizing radiation. Detection of breast tumor using radiometry is challenging as the intensity of thermal radiation received by the antenna is influenced by tumor stage, location, physiological conditions and the imaging setup. The controllable parameters for setting up a good imaging modality for early detection of breast cancer are ambient temperature (Ta), convection cooling of tissue surface (h), and tissue compression (c). Amongst these parameters tissue compression plays an important role since reducing the breast thickness increases visibility. In this work, fabrication of hydrogel breast tissue phantoms with varying concentrations of polyvinyl alcohol (PVAL) is carried out to mimic breast fat and glandular tissue properties for compression study. The phantoms were subjected to compression to investigate the mechanical properties for varying PVAL concentrations. A 3D numerical model was developed for phantom tissue compression simulations. Simulated tissue compression results were compared with phantom measurements for model validation.

The influence of tissue compression and external thermal modulation on passive detection of breast tumors using medical microwave radiometry was investigated using multi‐physics numerical modeling. A three‐dimensional numerical model of the pendant breast with 10 and 6 mm diameter tumors at varying depths (15 mm, 30 mm) was analyzed at thermodynamic equilibrium using a circular waveguide as the receive antenna. The contrast in the brightness temperature, ΔTB, between the unhealthy and healthy breasts was found to be significantly more for breast compression alone, compared to thermal modulation of the tissue surface, irrespective of tissue composition, tumor size, and depth. The study also concludes that small deep‐seated tumor with very low metabolic activity that is not detectable by a radiometer with 0.1 °C sensitivity could be detected under breast compression and short duration cold stress. Thus, detection of deep‐seated breast tumors can be significantly improved under controlled tissue compression with an optional cold stress. Bioelectromagnetics. © 2019 Bioelectromagnetics Society.

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