Abstract

AIM: Rhinosinusitis and olfactory disorders are thought to be dependent on the airflow inside the nasal cavity. Many reports appear that alterations of respiratory airflow may participate in various airway epithelial dysfunctions including nose, although the details have not been well known yet. On the other hand, the idea of aerosol transport into the sinuses via vibrating nebulization suggests that pressure fluctuations increase aerosol diffusion and ventilate dead spaces by flow induction. However, the adequate pulse frequency has not been well evaluated. This study used computational fluid dynamics (CFD) to investigate the effects of vibrating airflow on the forward direction volume flow rate (FVF) and the wall shear stress (WSS) in the olfactory cleft and middle meatus of the human nasal cavity.

METHODS: CFD simulations were used to investigate the nasal respiratory flow. A model was created from the sinus CT scan of three patients without sinonasal pathology. CFD analysis was performed to evaluate the effect of airflow vibrations with four different frequencies (25, 50, 75, and 100 Hz) on FVF and WSS in the olfactory cleft and middle meatus of the nasal cavity.

RESULTS: CFD analysis demonstrated significant increases of FVF and WSS on the olfactory cleft and middle meatus under conditions of nasal airflow with vibration.

CONCLUSION: The vibration stimulation might affect not only the drug delivery but also nasal epithelial functions. Vibrating aerosols may be a promising tool for mechanotherapy to improve the pathological status of nasal epithelial cells involving olfactory disorders and rhinosinusitis.