Quantitative Mapping of Fibrotic Tissue Mechanics via Brillouin Spectroscopy

Fibrosis is a pathological scarring process that disrupts tissue architecture, and is characterized by excessive extracellular matrix (ECM) deposition, leading to tissue stiffening and impaired organ function. Accurate quantification and spatial mapping of fibrotic tissue mechanics are critical for diagnosis, monitoring disease progression, and evaluating therapeutic responses. Here, we employ Brillouin microspectroscopy, a non-invasive, label-free optical technique, to quantify the mechanical properties of human fibrotic tissue in in situ. We show that Brillouin spectroscopy distinguishes fibrotic tissue from healthy tissue on the basis of localized differences in the complex longitudinal modulus and enables real-time monitoring of dynamic alterations in viscoelastic properties during fibrogenesis. To our knowledge, this is the first demonstration of Brillouin spectroscopy for in situ characterization of fibrosis and wound healing in a human model. These findings underscore Brillouin microspectroscopy's potential application as a promising diagnostic and monitoring tool for fibrotic diseases.