Enlargement of nasal vault diameter with closed septoturbinotomy.

BACKGROUND Septal deviation and inferior turbinate hypertrophy are important contributors to nasal airflow obstruction. In recent years, a closed septoturbinotomy, whereby a speculum is inserted into the nose and the blades are spread, has been shown to centralize the bony septum and outfracture the turbinates in most cases. It is a minimally invasive procedure that frequently corrects bony septal deviation and reduces enlarged inferior turbinates. However, the extent of vault enlargement by that method has not been quantified. The purpose of this study was to demonstrate and quantify the extent to which a closed septoturbinotomy enlarges the maximal diameter of the nasal vault. METHODS Measurements and silicone molds of the nasal vault were obtained before and immediately after performing closed septoturbinotomy in nine human cadavers. Measurements were taken with standardized graduated rubber tubing. Molds were obtained with commercially available sealant. RESULTS All cadaver noses demonstrated enlargement of maximal internal diameter of the obstructed side on both calibrated tubing and silicone mold measurements (p < 0.05). The mean postosteotomy-to-preosteotomy vault diameter ratio was 1.64 (range, 1.25 to 2.3) for the obstructed side and 1.16 (range, 1.0 to 1.4) for the unobstructed side. This 64 percent increase in radius permits a theoretical 7-fold increase in flow by Poiseuille's law. CONCLUSIONS Closed septoturbinotomy is a minimally invasive technique that enlarges the nasal vault in the overwhelming majority of cases. A clinical trial with rhinomanometry is needed to verify the extent of functional improvement.