The dissertation focuses on the issues of improving the quality of chronic laryngitis diagnosing in those exposed to exogenous chemicals.
The aim of the work is to promote the quality of chronic laryngitis diagnosing, based on the comprehensive clinical and instrumental study of the vocal apparatus, and evaluate risk factors for the above disease development.
The dissertation presents the findings of the comprehensive clinical and instrumental study of the vocal apparatus and voice function in 75 patients with chronic laryngitis exposed to chemical factors, 15 healthy individuals who constituted a control group and 15 patients with chronic laryngitis who were not exposed to chemicals as a comparison group. Data analysis was performed taking into account the characteristics of exogenous chemical exposure to nitrogen-containing compounds. All patients involved in the study underwent a comprehensive examination, including general clinical examinations, otolaryngological examination, specialized phoniatric examination with functional loads, determination of maximum phonation time (MPT), ENT endoscopy, laryngostroboscopy, acoustic analysis of Jitter, Shimmer, and NHR measures.
The analysis showed that catarrhal and subatrophic types of chronic laryngitis were most common in people exposed to chemical factors. Therefore, we evaluated the data of patients with catarrhal and subatrophic laryngitis. The patients were divided into groups, based on the type of chronic laryngitis, (group 1 included those with catarrhal laryngitis, group 2 was made of patients with a subatrophic type) and the level of chemical exposure to nitrogen-containing compounds at the manufacture.
We compared the results of a survey of patients with chronic laryngitis who worked in workshops where the content of chemicals in the air of the production environment did not exceed significantly the maximum allowable levels (MAL) – subgroup A, and those who were exposed to elevated levels of chemicals in the air – subgroup B. In total, subgroup 1A included 23 patients, subgroup 1B – 17, subgroup 2A – 20, and subgroup 2B – 15. In order to determine the characteristics of chronic laryngitis in the case of exposure to chemical factors, we compared the results of a comprehensive clinical and instrumental examination in patients of the main group and comparison group (patients with chronic laryngitis who had no contact with chemicals). At the same time, we chose only patients with chronic catarrhal laryngitis for comparison, because in most cases of subatrophic laryngitis there is a toxic effect or severe somatic diseases, so it is difficult to completely exclude the influence of chemical factors. Thus, we compared patients, having chronic catarrhal laryngitis, who were exposed to different levels of chemicals (subgroups 1A and 1B) and those who did not experience such an exposure (comparison group).
The dissertation provides a detailed description of the vocal apparatus and vocal function conditions in patients with chronic laryngitis, taking into account the nosological type and parameters of chemical exposure. It also identifies the most informative diagnostic criteria for improving the diagnosis of chronic laryngitis and determining its severity.
It was shown that acoustic analysis, involving such measures as Jitter, Shimmer, NHR, is the most informative and accessible way in the early detection of voice dysfunction in chronic laryngitis. The use of Jitter, Shimmer, NHR measures in the examination of patients with chronic laryngitis allows the objective detection of the vocal apparatus impairments in the early stages; it promotes the timely therapeutic and prophylactic measures, and prevents the progression of persistent vocal disorders. This method is sensitive, objective, accessible and suitable for large teams screening.
The conducted studies enhanced our insight into the occurrence of the vocal apparatus impairments in patients with chronic laryngitis against the background of chemical exposure.
The obtained results may promote the early detection of voice dysfunction in chronic laryngitis against the background of chemical exposure, timely treatment, prophylaxis and prevention of progression of persistent disorders of the vocal apparatus.
