Granulation formation following tracheal stenosis stenting: Influence of stent position

Objectives/Hypothesis: To determine whether stent-to-vocal fold distance influences morbidity following stent placement for tracheal stenosis. Methods: Fifty-five stent procedures (46 Montgomery T-tube [Boston Medical Products, Westborough, MA] and 9 Dumon stents [Novatech, Grasse, France]) were performed in 40 patients enrolled in this study. Results: The most common complication of stenting for tracheal stenosis was granulation (23 procedures, 41.82%). Of 43 procedures where the stent upper edge was located at or below the vocal folds, granulation occurred in 21 procedures (48.84%). Of 12 procedures where the stent edge was located above the vocal fold, granulation occurred in two procedures, or 16.67% (odds ratio - 4.773, P-.0458, χ² test). Among patients in whom the stent edge was located at or below the vocal folds, the granulation complication rate was higher in those with a stent-tovocal fold distance of <10 mm. Multivariate analysis revealed that the stent-to-vocal fold distance independently predicted granulation formation; an inverse correlation was identified between stent-to-vocal fold distance and granulation severity (n = 43, r = -.501, P =.0006;Spearman ranking test). Receiver operating characteristic curve analysis further demonstrated that a stent-to-vocal fold distance cutoff value between 9.5 and 11 mm had the best accuracy in predicting granulation formation. Conclusions: A stent-to-vocal fold distance of 10 mm was found to be a critical distance for discriminating granulation formation. Optimal stent-to-vocal fold distance should routinely be evaluated before stent placement.