Label-Free Virtual Histology for Rapid Cancer Diagnosis
Histological visualizations hold paramount importance in the management of clinical diseases and serve as a fundamental tool for biological comprehension. Nevertheless, prevailing methods employed for visualizing subcellular tissue morphology necessitate the utilization of exogenous histochemical labels, such as hematoxylin and eosin (H&E) stains, to achieve contrast in biological specimens. The imaging of these tissue samples mandates extensive chemical and mechanical preparation procedures prior to analysis. Therefore, these processes impose substantial labour intensiveness and fundamentally modify the structure and chemical composition of the tissue. In clinical settings, the application of histochemical staining techniques often leads to notable delays in providing critical clinical feedback, consequently impeding prompt decision-making pertaining to treatment strategies.
As one of our main focuses, we apply photon absorption remote sensing (PARS), to capture salient label-free contrast in biological specimens. Biomolecules present unique absorption spectra and unique responses to absorption events. These interactions can be leveraged to extract information on properties such as chemical bonding, and sample composition. By capturing most optical interactions (optical scattering, non-radiative and radiative absorption) as a pulse of excitation light is introduced into a specimen, PARS can provide exceptional insight into the composition of specimens. For example, when imaging a section of preserved human breast tissues, PARS captures both the radiative and non-radiative absorption fractions. These are combined to show a total absorption image shown in the figure. In addition, PARS may yield novel biomolecule-specific features such as the ratio of non-radiative to radiative relaxation processes, called the quantum efficiency ratio (QER). Combined with AI processing, the PARS may provide direct emulation of conventional histological stains such as hematoxylin and eosin (H&E). In the future, PARS may enable direct label-free histological imaging of unstained freshly resected tissues and ultimately in-situ, with any number of emulated histochemical contrasts.
As one of our main focuses, we apply photon absorption remote sensing (PARS), to capture salient label-free contrast in biological specimens. Biomolecules present unique absorption spectra and unique responses to absorption events. These interactions can be leveraged to extract information on properties such as chemical bonding, and sample composition. By capturing most optical interactions (optical scattering, non-radiative and radiative absorption) as a pulse of excitation light is introduced into a specimen, PARS can provide exceptional insight into the composition of specimens. For example, when imaging a section of preserved human breast tissues, PARS captures both the radiative and non-radiative absorption fractions. These are combined to show a total absorption image shown in the figure. In addition, PARS may yield novel biomolecule-specific features such as the ratio of non-radiative to radiative relaxation processes, called the quantum efficiency ratio (QER). Combined with AI processing, the PARS may provide direct emulation of conventional histological stains such as hematoxylin and eosin (H&E). In the future, PARS may enable direct label-free histological imaging of unstained freshly resected tissues and ultimately in-situ, with any number of emulated histochemical contrasts.