Ultraviolet photoacoustic remote sensing for virtual histopathology

Abstract

Conventional histopathology has involved cutting, fixing, embedding, sectioning, and staining of surgical tissue specimens and has been the gold-standard for tissue diagnosis including tumor margin determination for over a century. However, this process is laborious and time-consuming and can lead to delays in diagnosis that are typically weeks after a surgery. In as many as 20-40% of solid tumor surgeries, residual tumor tissue is left behind and repeat surgeries are required. To address this critical issue we propose a new form of microscopy, photoacoustic remote sensing (PARS), that is capable of histology-like imagery that could enable histopathological inspection of tissues while a patient is still on the operating table. This would enable a surgeon to go back and remove additional tumor tissues that are left behind. Using ultraviolet 266nm light, we obtain images of cell nuclei from fixed and fresh tissue specimens with strong correlation to traditional HE pathology.