As red blood cells flowing in capillaries pass through the focal volume of an optical coherence tomography (OCT) system, they will induce a transient change in back-scattering, leading to peaks in the intensity of the OCT signal. In recent years, an OCT method has been devised exploiting these intensity fluctuations to estimate the hemodynamic parameters, such as RBC speed and flux. In this work, using concurrent OCT and two-photon microscopy, we assess the accuracy of the technique, highlighting that single red blood cells can indeed be detected in OCT, in specific hemodynamic and experimental settings.
|