Optofluidic intracavity spectroscopy of canine hemangiosarcoma

The label-free technique of optofluidic intracavity spectroscopy (OFIS) uses light transmitted through a cellular body in a microfluidic optical resonator to distinguish different types of cells by their optical properties. The OFIS technique has differentiated canine hemangiosarcoma (HSA) cells from monocytes in peripheral blood mononuclear cells based on their distinctive transmission spectra. A single characteristic parameter indicative of strong multi-transverse-mode resonances was determined for each cell by forming a linear combination of the mean and standard deviation of the transmission spectra over one free spectral range, excluding the peaks of passive Fabry-Pérot cavities without cells. The difference in the characteristic parameters of HSA and monocyte samples was statistically highly significant with a p-value as low as 10(-6). The same method shows that the characteristic parameters of canine lymphoma and lymphocytes are distinct with p < 0.005. A receiver operating-characteristic curve constructed from t-distributions fit to the HSA and monocyte data indicates that 95% sensitivity and 98% specificity can be simultaneously achieved.