Electron microscopy assessment of the recovery of sinus mucosa after sinus surgery.

OBJECTIVES: To determine the level of injury to the maxillary sinus mucosa due to chronic infection and the capacity of sinus mucosa to recover after sinus surgery.
MATERIAL AND METHODS: Scanning and transmission electron microscopy (SEM and TEM, respectively) were used for examination of maxillary sinus mucosa at the time of endoscopic sinus surgery and 6 months postoperatively.
RESULTS: SEM showed non-ciliated cells, metaplasia, ciliary disorientation, abundant goblet cells, microvilli and compound cilia perioperatively. Six months postoperatively the numbers of non-ciliated cells and microvilli had increased but the degree of metaplasia and disorientation and the number of compound cilia had decreased. Perioperative TEM revealed metaplasia, disorientation, tubulus anomalies, compound cilia and one patient with short dynein arms.
CONCLUSIONS: As a result of this study we conclude that sinus mucosa repairs slowly after surgery. There are still many pathological findings in the mucosa 6 months postoperatively and some of these findings may even be irreversible. Patients need frequent follow-up after their operation and we suggest that a follow-up time for sinus surgery patients of at least 1 year should be allowed before final evaluation of the operation and its outcomes is made.