Quantitative phase imaging trends in biomedical applications

In the last decades, the understanding of the complex biological mechanisms that regulate the life and growth of single cells and their reciprocal interaction has steadily increased. In this process, Quantitative Phase Imaging (QPI) has emerged as an invaluable tool, thus providing a new way of investigating live cell behaviour in a dynamic, label-free and non-invasive modality. It has proved especially relevant to biomedical and diagnostic applications, as the information-rich quantitative phase data opens new channels to investigate pathophysiology. In this review, we expose the recent developments in the extraction of unique biological information, and we provide a schematic overview of the currently developed techniques. Specifically, we identify four different trends of relevance in the context of biomedical applications, namely QPI-cytometry, development of point-of-care devices, tomographic phase reconstruction techniques and learning-based approaches, providing a current insight in the way they are shifting our approach to the acquisition and treatment of QPI data.