Dark field microscopy for the endothelial glycocalyx study: first russian experience; the reproducibility of the method

Introduction and purpose. Endothelial glycocalyx is a protective structure of the vascular bed and is damaged in early stages of cardiovascular diseases. Dark field microscopy can determine the depth of penetration of red blood cells in endothelial glycocalyx to estimate the perfusion boundary region (PBR). The aim of this study was to test and validate this method. Materials and methods. The study involved 38 healthy volunteers aged from 28 to 65 years (18 women and 20 men). The sidearm dark field microscopy of the mucosal microvessels in the sublingual area was used to determine the depth of penetration of red blood cells in endothelial glycocalyx to estimate PBR. Results end discussion. The results indicate good tolerability of the test by patients. Our data on the structure of microvessels were highly reproducible and did not depend on the sampling region within sublingual area and on time intervals between sampling. PBR value was not gender-dependent. Conclusion. The dark field microscopy method passed the first step of validation, showing a good feasibility and tolerability, as well as high reproducibility of measurements that are independent of the sampling region and time intervals between sampling.