Estimation of oxygen saturation from erythrocytes by high-resolution spectroscopic optical coherence tomography.

We demonstrate the feasibility of estimating hemoglobin oxygen saturation (SaO(2)) from erythrocytes over a visible wavelength band using high-resolution spectroscopic optical coherence tomography (SOCT). We take SOCT spectra from individual cells on in vitro human blood phantoms and calculate SaO(2) by fitting the spectra to an analytical model. We also use diffusive spectroscopy (DS) measurements, which is validated by direct measurement of oxygen partial pressure, as a comparison. The result shows a reliable linear association between the SaO(2) derived from SOCT and the DS measurement, indicating this methodology has potential on in vivo applications to evaluate blood oxygenation.