A Comparative Study of Skin Phantoms for Microwave Applications.

In the here-reported study, we investigated the dielectric properties of three different skin-mimicking materials used in the reported controlled experiments for development and testing of microwave-range medical devices. Each of the phantom materials under consideration is tested in two forms: a thicker, larger block and a 2-mm sheet. The measured properties are compared to a reference of human skin tissue measurements from literature. Depending on the frequency range of the medical device in development, some phantoms are more suitable to represent human skin than others. We observe that all phantoms still show lower dielectric properties than the human skin reference, but are suitable representations of skin at microwave applications if used as 2-mm thin layers.

A Flexible Antenna Array with Integrated Switching Matrix for Breast Cancer Detection.

In this report, we introduce a flexible board combining a custom switching circuit and 16 integrated antennas for a time-domain ultrawideband radar for breast health monitoring in one device. The goal of this study is to assess the suitability of the flexible prototype for tumor detection using carbon-polyurethane experimental breast models and comparing the performance to an earlier prototype with a rigid switching circuit and 16 separate antennas. The flexible antenna array allows direct contact with the patient skin while reducing the number of RF and DC cables needed in the previously reported system. We evaluate that the introduced flexible board successfully transmits and receives the microwave signals, and isolates tumor responses using a simple method. However, we observe that the board exhibits an early signal in the recordings of all antenna pairs which corresponds to direct cross-talk on the board and is not part of the signal that has passed through the phantom.

Microwave Radar for Breast Screening: Initial Clinical Data with Suspicious-Lesion Patients.

We present results of a statistical analysis of patient measurements with a time-domain multistatic microwave radar for early breast cancer detection. The scanned patients varied in age, but all showed a suspicious lesion on a previous breast screening with a mammogram or MRI. We assess the correlation between the signal response of preprocessed data and specific patient attributes. The goal is to use the results towards optimizing the clinical prototype, in order to improve the overall signal quality for a future large-scale study.