Does Inhaled Pollen Enter the Sinus Cavities?

The Impact of allergic and nonallergic rhinitis on pediatric sinusitis

“…Finally, three of the eight patients who did not develop nasal responses showed radiographic changes. This study demonstrating changes in the sinuses after nasal provocation with allergen is probably not explainable by direct entry of allergen into the sinuses, because another study, by Adkins et al [18], demonstrated that radiolabeled ragweed pollen, after nasal inhalation, does not enter the sinus cavities. Only one study has evaluated the co-prevalence of chronic sinusitis and nonallergic rhinitis.…”

Nasal challenge with allergen leads to maxillary sinus inflammation

“…However, a major problem with this hypothesis is that the sinus ostia are connected to the nasal cavity by narrow, convoluted bony channels, making it very unlikely for pollen to penetrate the maxillary sinus. Adkins et al 19 performed nasal allergen challenges in nonatopic subjects with Tc99m-labeled ragweed pollen and found intense activity in the nasal cavity but no activity in the paranasal sinuses. Studies of IgE levels and gas composition support the limited exchange between the nasal cavity and the sinuses.…”

Genetics and phenotyping in chronic sinusitis

“…In general, aeroallergens do not access healthy sinus cavities, and this is likely to be even truer with the occlusion of the sinus ostia that occurs with this disease. 66,67 However, these patients do display worsening of sinus inflammation after aeroallergen exposures, and nasal challenges exacerbate eosinophil influx into the sinuses. 61 In the absence of direct access to the sinuses, these studies suggest systemic and/or local lymphatic recirculation of inflammatory cells (ie, eosinophils, eosinophil precursors, 68 dendritic cells, and T H lymphocytes) between the nasal epithelium, nasal/sinus lymphatics, bone marrow, and sinus tissue that drive this disorder.…”