RBC core detection

Detection of channel walls, diameter measurement-Automatic or semis-automatic detection of the red blood cell - User interface

In microcirculation, red blood cells (RBCs) tend to migrate toward the centre of the vessel leaving a region of a cell depleted layer or cell-free layer (CFL) at the vessel wall and a core of RBCs at the centre. This heterogenous distribution of cells has an effect on the blood apparent viscosity and the exchanges of gases and nutrients between the RBCs and the vessel. Understanding the formation of the CFL and obtaining accurate measurement of it is paramount for furthering development of devices such as drug administration. In this report a general semi-automatic program developed in MATLAB to quantify the thickness of the CFL for different channel geometries and image quality is proposed. Our program enables the use of method based on intensity, a method using the gradient of the intensity and a method based on spatiotemporal variation. The main features are reported, and the performance is demonstrated on different image sets. A pure automatic detection is limited with the most visually correct using the spatiotemporal method, however proposed thresholding through automatic detection allows for quality controls through manual adjustments. With a semi-automatic approach RBC core variability between 3% to 8% was found when the test user was tasked with repeating the analysis of the same set. Our program provides, users without programming ability, a user-friendly interface that can extract CFL automatically with quality control through manual adjustments.