Experimentally induced rhinosinusitis in rabbits

The purpose of this study was to develop an experimental rhinosinusitis model by using bacteria-added absorbable material for temporary ostial obstruction.

Absorbable gelatin sponge was inserted between the endoturbinals and the ostium of the sinus. In the first group, the effects of surgical procedure and Gelfoam on ostial mucosa were examined macroscopically. In the second group Gelfoam was moistened with Staphylococcus aureus (ATCC 25923). The sinuses of rabbits were examined by coronal com puted tomography before each surgical procedure and sacrifice. The animals were sacrificed at the first, second, fourth eighth, and tenth weeks. Histologic and microbiologic examinations were performed.

In the first group, fibrotic bands and adhesions were observed between the ostium of the maxillary sinus and the endoturbinals in the first and second week. In the second group, a thick purulent discharge that invariably filled the sinuses of the inoculated side was seen after the first week of induction, and opacity, which was determined radiologically, did not disappear until the end of the study.

In this study, an experimental rhinosinusitis model was accomplished. It is currently believed that obstruction of the ostium with mucosal edema, polyps, or tumour leads to maxillary sinusitis. In this model, the pathogenesis of human sinusitis was imitated by temporary occlusion of the ostium with bacteria-added Gelfoam. This model can be used in further studies to explore the role of the ostium in the pathogenesis of sinusitis.