Quantification of house dust mite deposition in the paranasal cavities following functional endoscopic sinus surgery

House dust mites (HDM) are a major perennial allergen source and a significant cause of allergic diseases worldwide. However, inhalation exposure to HDMs in the paranasal cavities remains unclear. This study describes and quantifies HDM deposition and potential allergic impact in the paranasal cavities for patients who underwent functional endoscopic sinus surgery (FESS). HDM deposition in postoperative nasal models was numerically investigated based on the largest patient cohort with 8 post-FESS nasal airway subjects. The effects of body position on allergen deposition were investigated. HDM with a smaller diameter was deposited dispersively in the paranasal cavities, and compared with healthy adults, there were rare fecal pellet deposits in the post-FESS of the paranasal sinuses, except for the frontal sinus. The large particles were mainly deposited in the nasal septum, and a few were deposited in the sinuses. In a lying position, more HDM is deposited outside the paranasal cavities. Under exercising conditions, the deposition rates in the nasal cavity and ethmoid sinus increased, while those in the frontal sinus decreased. HDM fecal pellets could enter all sinuses following FESS, and the smaller were deposited dispersively in the paranasal cavities, which may contribute to allergic respiratory disease. In addition to the respiratory flow rate and particle size, body position is also a notable factor in HDM deposition. The digital post-FESS nasal subject database with HDM fecal pellet deposition data can offer a valuable reference for the treatment and prevention of recurrence following endoscopic sinus surgery.