Lorenzo Crocco: Recent Advancements in Contrast-Enhanced Microwave Imaging for Medical Diagnostics

Microwave imaging is an emerging diagnostic technique that uses electromagnetic fields in the microwave frequency range to extract clinically relevant information, while relying on safe and cost-effective instrumentation. A key challenge is the extraction of useful signals from measurements, due to the intrinsic complexity of wave–matter interactions. To address this limitation and improve the sensitivity and specificity of microwave imaging for diagnosing and monitoring pathological conditions, magnetic nanoparticles have been proposed as contrast agents. These nanocomposites are particularly suitable because they can induce variations in the magnetic properties of otherwise non-magnetic media. In addition, their microwave response can be remotely controlled by applying a low-frequency magnetic field of appropriate strength. To date, two main applications have been explored: early breast cancer detection and bone regeneration monitoring. In the former, nanoparticles are dispersed in water-based solutions and selectively accumulate in tumor tissue. In the latter, nanoparticles are embedded within magnetic scaffolds, serving both as therapeutic mediators and as tools for monitoring tissue regeneration. This work reviews the key aspects of contrast-enhanced microwave imaging, along with the specific requirements of these two applications. Then, the design and implementation of a dual-purpose microwave tomographic system capable of supporting both use cases is presented.