Acoustic drug delivery to the maxillary sinus.

Acoustic drug delivery (ADD) is an innovative method for drug delivery to the nose and paranasal sinuses and can be used to treat chronic rhinosinusitis (CRS). The underlying mechanism of ADD is based on the oscillatory exchange of air between the nasal cavity (NC) and the maxillary sinus (MS) through the ostium, which assists with the transfer of the drug particles from the NC to the sinuses. This study aims to examine the efficacy of ADD for drug delivery to the MS using an acoustic wave applied to nebulised aerosols entering the nostril. Here, the effect of acoustic frequency, amplitude, and nebulisation flowrate on the efficiency of ADD to the MS is investigated experimentally. A computational fluid dynamics model was also developed to understand the deposition and transport patterns of the aerosols. The results showed that superimposing an acoustic frequency of 328 Hz, which is the resonance frequency of the selected 3D printed model of the NC-MS combination, on the nebulised aerosols could improve the efficiency of the drug delivery to the MS by 75-fold compared with non-acoustic drug delivery case (p < 0.0001). The experimental data also shows that an increase in the amplitude of excitation, increases the concentration of aerosol deposition in the MS significantly; however, it reaches to a plateau at a sound pressure level of 120 dB re 20 µPa.