[Automatic erythrocytometry in a robotized microscope MEKOS-Ts1]

Measurements of the form and size of erythrocytes are needed in the diagnosis of a number of diseases. However, such measurements, if made manually, are a labor-consuming and often inaccurate method, which ensures the determination of a very limited number of parameters. Hardware/software unit MEKOS-C1 enables an automated examination of blood smear, thus speeding up significantly the analysis and ensuring a more complete and accurate information. The possibilities of unit MEKOS-C1 were evaluated for the diagnosis of ovalocytosis. Blood smears of 19 patients from the Russian Pediatric Clinical Hospital, including 8 patients with inherited ovalocytosis, 1 patient with spherocytic ovalocytosis and 10 patients without the disease, were made use of Erythrocytes were isolated in the images of preparations and the contour of each cell was approximated by ellipse. The ratio between ellipse semi-axes served as a measure of erythrocytes' ovality. The mean ratio of semi-axes (RS) and the index of ovalocytosis (IO), i.e. a ratio of the mean maximum diameter to the mean minimal diameter, were calculated for each smear. Manual IO measurements were made in all preparations as a control. Since an additional error can enter the result because of the irregular smear nature and impossibility to standardize completely the technology of smear preparation, the data, obtained from two different smear parts and from parallel preparations, were compared. The reliability, stability and good reproducibility of the automated measurement results were demonstrated. The mean erythrocytes' RS correlated well with IO, obtained manually, and did not virtually differ from RS, measured in the automated manner. The mean RS value of erythrocytes, obtained from patients with inherited ovalocytosis, significantly differed from the control values, which is indicative of a high information density of the discussed parameter. Therefore, RS, when measured automatically, is a reliable and convenient characteristic of erythrocytes' ovality under the conditions of using the ordinary technique of smear preparation.