Correlation mapping nano-sensitive optical coherence tomography (cm-nsOCT): a novel technique for structural characterization

Abstract

Optical coherence tomography (OCT), a non-invasive label-free depth resolved imaging technique, facilitates cellular level structural and functional imaging of living animal and human tissues, but the structural sensitivity and resolution are fundamentally limited to microscale. Detection of structural changes in biological samples at nanoscale poses a significant challenge to both researchers and healthcare professionals. Furthermore, when considering physiological processes, it is desirable to be able to resolve these structural changes both spatially and temporally. Here, we present a novel method for detecting nanoscale structural changes non-invasively. This technique is based on adaptation of the correlation mapping approach to nano-sensitive optical coherence tomography (nsOCT). Our work describes the principles of this technique and demonstrates the feasibility of correlation mapping nano-sensitive optical coherence tomography (cm-nsOCT) by monitoring internal structural changes within different objects, including human skin in vivo. Structural changes can be visualized at each point in the sample over space or time. The experimental results show new possibilities for the study of structural changes, without the need for biomarkers or labels. Thus, cm-nsOCT could potentially offer exciting and far-reaching opportunities for early disease diagnosis, as well as myriad applications for researchers.