Label-free identification of human glioma xenograft of mouse brain with quantitative ultraviolet photoacoustic histology imaging.

The ability to unveil molecular specificities of endogenous nonfluorescent chromophores of ultraviolet photoacoustic imaging technology enables label-free histology imaging of tissue specimens. In this work, we exploit ultraviolet photoacoustic microscopy for identifying human glioma xenograft of mouse brain ex vivo. Intrinsically excellent imaging contrast of cell nucleus at ultraviolet photoacoustic illumination along with good spatial resolution allows for discerning the brain glioma of freshly-harvested thick brain slices, which circumvents laborious time-consuming preparations of the tissue specimens including micrometer-thick slicing and H&E staining that are prerequisites in standard histology analysis. The identification of tumor margins and quantitative analysis of tumor areas is implemented, representing good agreement with the standard H&E-stained observations. Quantitative ultraviolet photoacoustic microscopy can access fast pathological assessment to the brain tissues, and thus potentially facilitates intraoperative brain tumor resection to precisely remove all cancerous cells and preserve healthy tissue for maintaining its essential function.