STUDY OF OLFACTORY FUNCTION IN RESIDENTS OF THE SIBERIAN METROPOLIS IN NORMAL AND AFTER COVID-19

The olfactory function together with the respiratory and protective functions ensures the comfort of human nasal breathing, and the olfactory analyzer simultaneously with the visual and auditory analyzers is the most important source of information about the smells of the surrounding world coming when inhaling through the nose. Olfactory dysfunction is animportant symptom that can indicate serious violations of the functioning of human organs and systems, however, the current methods of olfactory function research are only qualitative in nature and have a huge dependence on the subjective perception of both the patient and the doctor, which makes it difficult to assess the sense of smell in clinical practice.
A study was conducted to assess olfactory function in healthy people, in people who have had COVID-19, and people with inflammatory diseases and injuries of the nose or head. Based on the study, a technique for digitizing the results of the olfactory function study was developed and indicators of the relative norm of olfaction for residents of the Siberian megalopolis in normal and after COVID-19 were obtained. The correlation of inflammatory and obstructive disorders of the ENT organs and olfactory dysfunction was revealed. Injuries to the nose and head also contributed to impaired sense of smell in patients. It was found that when self-evaluating patients tend to overestimate the quality of their sense of smell. There was also a decrease in olfactory function in the elderly, which is associated with neurodegenerative processes affecting all structures of the olfactory analyzer. Individuals who underwent COVID-19 without impaired olfactory function had higher olfactometryresults compared to patients who had hyposmia after COVID-19. However, studies by D. Brann et al. In mice, it is assumedthat the coronavirus does not enter directly into neurons, but instead can target supporting cells and stem cells of the olfactory epithelium [5]. In previous studies on mice, it was shown that the precursor of the modern virus penetrates the brain through the olfactory tract, and since the viruses are very similar, it is likely that this path of propagation to the brain is possible for the new coronavirus.
The olfactometry proposed by us is a chemosensory test that allows us to establish a more accurate (compared to previous research methods) level of olfactory dysfunction, since it is possible to specify the minimum concentration of an odorous chemical substance at which the patient can identify the smell. Also, this method allows you to compare the patient's result with the indicator of the relative norm of olfactory function for the age group of this patient.
The use of this method for detecting olfactory dysfunction contributes to timely diagnosis and accurate planning of further medical tactics for the management of a patient with hypo- and anosmia, including after COVID-19.

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