Objective: to determine the morphological features of proliferative processes in the mucosa of the nasal cavity and paranasal sinuses (PNS) in combination treatment aimed at restoring the olfactory analyzer. Material and methods. The investigators performed septoplasty and submucosal nasal septum resection in 120 patients with the deviated nasal septum (Group 1) and medical treatment in 50 people with chronic bacterial infection of the PNS (Group 2). All patients received combination treatment (antimicrobial therapy, laser therapy, and aromatherapy, etc.). A control group consisted of 22 healthy individuals. The activity of mitochondria and lysosomes was determined in the peripheral blood T lymphocytes; impression smears taken from the nasal mucosa were cytologically analyzed before surgery and after the combination therapy. Results. Dysosmia lasting 3 to 5 years was accompanied by hyperemia, edema, increased vascular permeability, and large numbers of eosinophils with moderate degenerative changes and macrophages. The longer than 3 years' duration of the chronic process led to pronounced degenerative processes, neutrophil infiltration of leukocytes with toxic granulation - to a smaller number of epitheliocytes cells and the appearance of fibrin fiber in the secretion. The combination therapy in both groups normalized succinate dehydrogenase activity in the presence of a high cell diversity in the impression smears, the normalized activity of detached mitochondria, and the decreased arousal and atypical activity of clustered mitochondria. Conclusion. The combination therapy has a positive impact at the cellular and subcellular levels. Analysis of the activity of succinate dehydrogenase, impression smears from the nasal mucosa may help in predicting the duration and efficiency of therapy in rehabilitation after septoplasty and nasal septal resection and in medical treatment for chronic bacterial rhinosinusitis.