V.S. Kozlov, S.K. Zhukov, Yaroslavl State Medical Academy, Yaroslavl, Russia. The incidence of bronchial asthma has steadily increased in the past decade, both in Russia and abroad. Not only has the incidence changed, but also its forms, with severe, hormone-dependent forms becoming increasingly common. Pathological changes in the nasal cavity and paranasal sinuses play a significant role in the development of bronchial asthma. According to various authors, the prevalence of this pathology in patients with bronchial asthma ranges from 30% to 95.5%. Treatment of this patient population is an exceptionally challenging task, as surgical interventions can cause severe exacerbations of bronchial asthma. At the same time, persistent chronic upper respiratory tract infection in bronchial asthma completely precludes the possibility of sustained remission of this disease. All of this makes the search for an adequate treatment strategy for chronic rhinosinusitis in patients with bronchial asthma crucial. The YAMIK sinus catheter, developed in 1985 by G.I. Markov and V.S. Kozlov, operates by creating controlled pressure in the nasal cavity and paranasal sinus system, allowing for non-invasive evacuation of pathological secretions. The YAMIK sinus catheter also allows for prolonged filling of the paranasal sinuses with medicinal mixtures. The non-invasive, comprehensive therapeutic effect of the YAMIK sinus catheter on the mucous membrane of all paranasal sinuses is extremely important in patients with bronchial asthma, helping to eliminate the source of chronic infectious sensitization. Eliminating this source has a positive effect on the bronchopulmonary system. A comprehensive examination of the paranasal sinuses in patients with bronchial asthma using CT and MRI revealed that paranasal sinus lesions are most often combined. Isolated frontal sinusitis and sphenoiditis were not observed in our observations. Bilateral maxillary ethmoiditis was observed most frequently (34.3%), with unilateral maxillary ethmoiditis being somewhat less common (21.7%). Pansinusitis (12.1%) and hemisinusitis (12.8%) were equally common. All of this indicates that multiple, total, and subtotal lesions of the paranasal sinuses are predominant in bronchial asthma. This fits well with the theory of simultaneous damage to all parts of the respiratory tract in patients with bronchial asthma, which is systemic in nature and dictates a comprehensive approach to the treatment of upper respiratory tract lesions in patients with bronchial asthma. Thus, the conducted studies have shown that in 73.6% of cases, the onset of bronchial asthma is preceded by pathological changes in the paranasal sinuses, so their timely treatment is a priority. To more thoroughly understand the pathological relationships between the upper and lower respiratory tract in bronchial asthma, we conducted an in-depth analysis of cytobiochemical parameters of paranasal sinus contents. This was made possible only by the use of the YAMIK sinus catheter, which allows for non-invasive collection of contents from all affected paranasal sinuses. In some cases, the YAMIK sinus catheter was ineffective. In these patients, corrective surgery on intranasal structures was performed to improve the effectiveness of subsequent use of the YAMIK sinus catheter. The effectiveness of these microsurgical procedures was greater in cases of vasomotor and polypous sinusitis and less so in cases of purulent and purulent-polypous sinusitis. In any case, we considered the endonasal microsurgical interventions performed as the first stage of complex therapy aimed at solving the main problem - creating anatomical prerequisites for the normal functioning of the anastomoses. A study of mucociliary clearance before and after treatment of chronic sinusitis in patients with bronchial asthma also proved the positive role of vacuum drainage with the YAMIK sinus catheter in normalizing the condition of the mucous membrane of the nasal cavity and paranasal sinuses. Analysis of the results of biochemical and cytological studies showed that as a result of treatment, the number of neutrophils and lymphocytes in the sinuses decreases in the infection-dependent form of bronchial asthma, which indicates abatement of the chronic inflammatory process. The number of eosinophils and mast cells also decreases, which indicates a decrease in sinus allergization; the number of respiratory epithelial cells decreases, which indicates the onset of normalization of the mucous membranes of the paranasal sinuses. Of particular interest are the data from a functional study of pulmonary respiration in the patients with bronchial asthma examined by us before and after treatment. They indicate a clear tendency towards persistent remission of bronchial Asthma. The results of the resolution of chronic foci of upper respiratory tract infection were more clearly evident in patients with infection-related asthma than in those with atopic asthma. This is apparently due to the fact that in atopic asthma, not only rhinobronchial mechanisms are important, but also a number of additional factors. Nevertheless, even in atopic asthma, a certain improvement in the course of asthma was diagnosed with the resolution of upper respiratory tract pathology. Data from a comprehensive pulmonary examination, including a functional examination, data from a special questionnaire, the dynamics of the use of sympathomimetic drugs, and a comparative characteristic of daily asthma attacks, show a clear dynamic of improvement in the course of bronchial asthma after the elimination of foci of infectious and atonic sensitization in the paranasal sinuses. Having analyzed a group of patients with worsening bronchial asthma, we came to the conclusion that it was associated with a special variant of the aspirin triad, the course of which develops according to The disease follows specific laws and is only partially related to paranasal sinus pathology. Follow-up observation of patients with bronchial asthma after treatment for chronic rhinosinusitis demonstrates the lasting effect of sinus sanitation using vacuum drainage with the YAMIK sinus catheter. Our study suggests that treatment of chronic rhinosinusitis with the YAMIK sinus catheter not only normalizes the condition of the paranasal sinuses but also leads to long-term and stable asthma remission. This is likely due to the YAMIK sinus catheter's effective elimination of infectious and atonic sensitization foci in the paranasal sinuses, which is impossible with traditional sinus treatment methods.