Instrumental Non-Invasive Diagnostics of the Depth of Skin Burn: Current Opportunities and Unsolved Problems

Abstract

Introduction. Burns of various etiologies are on the 3-4 place in frequency among all injuries, they are associated with a high percentage of complications, disability and mortality. Currently, a single algorithm for objective verification of the depth of skin damage has not been developed. Numerous diagnostic technologies used to solve this problem require systemic analysis.The aim of study was to analyze current literature data on technologies for instrumental diagnostics of the depth of thermal damage to the skin.Materials and methods. A search for literary sources in databases was conducted using eLIBRARY.RU, PubMed, Cyberleninka databases. The period of publications was limited to 2011-2020.Results. The method of objective "gold standard" verification of thermal damage to the skin remains a biopsy followed by morphological examination, but the method's traumaticity does not allow it to be used for monitoring the course of the process in dynamics, for multi-focal studies. Among non-invasive methods, dermatoscopy and video microscopy are noted, but the small imaging area and the need for direct contact of the device with the skin surface limit the use of these methods. Laser Doppler flowmetry and imaging are fairly accurate non-contact methods that allow assessing the condition of a burn wound in real time. The method is not applicable to wounds with blisters, insufficient sanitation. Laser speckle contrast imaging is used to evaluate blood flow and is based on the analysis of speckle structure fluctuations. The method allows determining the degree of burn damage depending on changes in the blood flow. However, the method is difficult to apply with a vessel diameter sized 40 microns. The method is sensitive to movement and internal factors. Infrared and Raman spectroscopy are technique for evaluating vibrational patterns in a particular spectrum, these can be used to identify a molecule or determine its structure. Simultaneous use of spatial frequency visualization and speckle imaging demonstrated a high level of correlation with the results of histological research, which makes the use of these methods promising. Ultrasound also provides a proper correlation with histological data, but it is an imperfect method due to inaccuracies in determining the thickness of the epidermis, dermis, and scar condition. Optical coherence tomography (OCT) is a non-invasive optical method that allows obtaining high-resolution images of skin architecture in real time. The high level of compliance of the visualized structures, in particular, layers, appendages and vessels of the skin, with histological findings, gave this method a name "optical biopsy". Anatomical congruence of normal and damaged skin was established in an experiment between histology and OCT.Conclusion. Early assessment of the depth of thermal damage to the skin is crucial for choosing a personalized treatment strategy for the burned. None of the modern diagnostic methods is universal. Multimodal approaches to diagnostics are the most effective.