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1Development of the analysis of experimental data in laser diffractometry of erythrocytes
M.S. Lebedeva1*, E.G. Tsybrov2, S.Yu. Nikitin1
1-Faculty of Physics, Lomonosov Moscow State University, Moscow, Russia 2- Faculty of Computational Mathematics and Cybernetics, Lomonosov Moscow State University,
Moscow, Russia
Laser diffractometry is known to be one of the methods of studying ensembles of red blood cells. The purpose of our work is to create a set of algorithms that would allow us to analyze real diffraction patterns with high accuracy and to obtain central moments of the distribution of red blood cells by size-shape and deformability. At present, a number of algorithms that take into account the degree of uniformity of the blood sample under study and the area of analysis of the diffraction pattern has been developed in our laboratory. The numerical experiment shows a high accuracy of such algorithms, however, in practice, the final result of the diffraction pattern analysis is influenced by many parameters, ranging from the method of preparing a suspension of cells to the resolution of the diffraction pattern registration system.
In this work we compare the experimental results obtained using the algorithms we developed with the results calculated directly by processing microscopic images of red blood cells to understand which of the parameters play a key role in the analysis. We selected the following parameters of cell ensembles for the analysis: the relative widths of the size distribution (RDWR) and deformability distribution (RDWD) of erythrocytes. These values are introduced by analogy with the RDW parameter of a standard blood test and they are dimensionless.
As an example, the result of processing experimental data for a blood sample from a healthy donor is shown below.
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Fig.1. On the left there is a graph of red blood cells size distribution obtained by processing images of cells from a microscope.
One of the diffraction patterns for this donor is shown on the right.
The calculated values of RDWR were 0.0428 and 0.0874 for microscopy and diffractometry, respectively. This can be explained by the fact that laser diffractometry takes into account a large number of variations in values than microscopic analysis. Currently, there is a reason to believe that RDWR value is 3-6% for a healthy donor.
At the moment, the key factors affecting the accuracy of the results obtained by laser diffractometry include the method of preparing a blood sample, the degree of uniformity of the studied ensemble of cells, the area of analysis of the diffraction pattern, the noise level and the resolution of the diffraction pattern registration system.
The main goals for our further work are to accumulate the experimental data on healthy donors and patients with socially significant diseases (for example, diabetes mellitus, cardiovascular diseases), to search for correlations between the parameters of the red blood cell ensemble and these diseases, as well as to continue the process of verification of data processing algorithms developed by us.
The study was conducted with the financial support of the scholarship grant of the "BASIS" foundation № 23-2-2-36-1.
