A potential role for nasal obstruction in development of acute sinusitis: An infection study in rabbits

The sequence of events that predispose to the onset of sinusitis are usuall y attributed to pathophysiologic factors within the ostiomeatal complex. Os tial compromise or obstruction with reduced clearance of antral pathogens h as been implicated as a major factor that contributes to early sinus diseas e. Recent work in this laboratory has indicated that other processes may al so contribute to this cascade. Using an infectious model in rabbits, the ro le of nasal obstruction in early, acute sinusitis was studied. Unilateral n asal closure was followed by bilateral inoculation with 10(8) CFU of Strept ococcus pneumoniae type 3. Antral gas composition was examined on days 1, 2 , 3, 5 7, and 14, and swabs obtained for culture. Representative rabbits un derwent CT scans to evaluate changes in nasal and sinus mucosa. Results sho wed a significant increase in CO2 and a trend toward a decrease in O-2 on t he obstructed side. There was also a significant decrease in obstructed CO2 levels from postoperative days (POD) 1-14. Acute sinusitis was not observe d in any animal; however, nasal obstruction gave rise to a dramatic prolong ation of bacterial retention. On days 2-7 bacteria was consistently culture d from the obstructed side only. CT scans on POD 2 and POD 3 showed mucosal thickening in the sinus and infundibulum on the obstructed side, indicativ e of sinus pathology. These results indicate that nasal obstruction may be a key factor in the cascade of events that predispose to the onset of sinus disease.