The impact of changes in nasal biomechanical properties caused by allergic rhinitis on uneven airflow distribution and exacerbation of allergic reactions

Allergic rhinitis (AR) is a common chronic condition characterized by an exaggerated nasal response to allergens, significantly impacting airflow and exacerbating symptoms. Structural changes in the nasal cavity, such as septal deviation and turbinate hypertrophy, disrupt normal airflow dynamics, prolonging allergen retention and intensifying inflammation. The interplay between anatomical abnormalities, increased inflammatory mediators, and biomechanical feedback mechanisms creates a cycle that amplifies AR symptoms. Methods: Based on the results of thin-layer CT scans of the nasal cavity for 20 patients with nasal septum deviation and 20 healthy northern Chinese individuals, a three-dimensional reconstruction was performed using surface reconstruction finite element partitioning methods to simulate the airflow characteristics through the nasal airways. Results: In individuals with nasal septum deviation, the bilateral nasal airflow distribution is primarily on the side with the wider airway, with the maximum airflow concentrated in the middle part of the total nasal passage on the wider side; the nasal airway pressure drops most rapidly at the site of greatest deviation, accounting for 79.65% of the total pressure difference across the airway. In healthy individuals, the bilateral nasal airflow is influenced by the nasal cycle, predominantly occurring on one side, with the maximum airflow distributed in the middle and lower parts of the total nasal passage; the nasal airway pressure drops most rapidly at the nasal threshold, accounting for approximately 58.78% of the total pressure difference across the airway. Conclusion: Using computer simulation to establish a numerical model of the nasal structure and analyze the relationship between anatomical abnormalities and airflow field characteristics represents a feasible scientific approach for studying the correlation between nasal structure, function, and disease. This can provide references for surgical treatment plans aimed at optimizing airflow paths and altering airflow distribution, as well as for personalized assessments before and after surgery. These biomechanical changes are crucial for developing targeted surgical and medical treatments, enabling more accurate disease assessment and personalized treatment plans. This knowledge also inspires the development of innovative therapies, improves symptom control, and offers hope for more effective AR management in the future.