Microwave Time-Domain Radar: Healthy Tissue Variations Over the Menstrual Cycle

In this study, we follow a healthy patient volunteer with daily breast scans using our time-domain microwave radar monitoring system. Over the course of a 28-day period, which corresponds to the time frame of the menstrual cycle, we perform a total of 54 scans per breast. Our breast monitoring system uses a time-domain, multistatic radar approach with 16 wideband sensors. We first directly compare the recorded signals for each scan, then examine reconstructed images for each breast, and compare how they vary day by day. Images are compared using the structural similarity index, and based on their pixel intensities. We further estimate the daily average tissue permittivity for each breast. The results demonstrate that our system is able to detect variations in the breast tissues over the monthly period; however, we estimate that the quality of these changes differs from those that would appear due to a malignant growth. The tissue changes seen in this trial are not likely to affect the outcome of long-term monitoring for the purpose of abnormality detection; however, measurements on a larger population are required before wider conclusions can be made.