Evaluation of Intranasal Ostium in External Dacryocystorhinostomy

Objective: The investigation of factors affecting the dimension and configuration of the intranasal ostium in successful external dacryocystorhinostomy (DCR). Material and Methods: Fifty-one patients were enrolled within this study. During operation, dimensions of bone window were measured. In the postoperative sixth month, changes in bone window size were evaluated using spiral paranasal tomography, and the intranasal ostium was examined with nasal endoscopy. Results: There were 19 patients who underwent DCR and 32 patients who underwent DCR+silicone tube intubations (SI). The mean bone window size was 214.37 mm2 during operation and 214.87 mm2 after six months. The mean intranasal ostium size was measured as 51.42 mm2 for patients who had undergone DCR and 28.66 mm2 for the DCR+SI cases. The endoscopic appearance of the ostium was observed as oval or round for the DCR cases and in slit form for the DCR+SI cases. A multiple logistic regression model showed that silicon tube intubation posed an 11 times greater risk for configuration distortion in the intranasal ostium (p=0.0079). Conclusion: Postoperative intranasal ostium size has a relation with the intraoperative bone window size. The difference of mean intranasal ostium sizes of DCR and DCR+SI cases was not statistically significant. However, because SI gives rise to ostium configuration by triggering fibrosis, it should not be carried out unless absolutely necessary.