Automated morphometric studies of collagen fibers as an auxiliary method for diagnosing cold injury

Background. Cold injury is one of the most significant problems for the northern regions of the Russian Federation. Frostbite is defined as a complex of changes caused by the action of low temperatures, which lead to morphological changes in damaged tissue structures. As a result, the skin with underlying tissues and the intercellular matrix, the components of which are collagen fibers, are damaged, which eventually leads to remodeling and a protracted course of the wound process. Morphometric studies in combination with quantitative analysis of microphotographs (histological specimens) using GIS technologies make it possible to distinguish altered collagen fibers under the influence of low temperatures from relatively healthy tissues.

The aim of the study. To assess the possibility of using computer analysis of microphotographs in  a  complex of morphometric studies of collagen fibers in local cold injury.

Materials and methods. The study included 84 patients with III and IV degree frostbite of the lower extremities. Morphological study of tissues and microphotography were performed using Leica DM2500 microscope (Leica, Germany). The thickness of  collagen fibers was measured based on  visual measurements of characteristic areas of the microphotograph. Computer analysis of tissue microphotographs of  the  zone of cryoinjury was performed using the ArcINFO software (Esri, USA). Statistical processing of the study results was carried out using the SPSS Statistics software package (IBM Corp., USA). Graphs and diagrams were constructed using MS Office Excel (Microsoft Corp., USA).

Results. With frostbite, severe tissue damage occurs, accompanied by the destructive processes of the extracellular matrix components. Low temperatures contribute to  changes in the width and orientation of collagen fibers in the damaged area. In  this  regard, a change in the texture of the histological specimen image leads to achange in the numerical characteristics of the standard deviation of the curvature coefficient in the studied area of the microphotograph. Thus, in the late reactive period, the described complex of morphometric studies makes it possible to classify particular microphotograph as having pathological signs or as a sample of healthy tissue.

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