CT comparison of the nasal airway anterior and posterior to the piriform aperture in patients with and without nasal obstruction.

The nasal airway anterior to the piriform aperture was smaller in patients with nasal obstruction due to skeletal nasal stenosis than that in controls. On the contrary, the nasal airway posterior to the piriform aperture was similarly large between patients with and without nasal obstruction. Furthermore, in patients with nasal obstruction, the anterior nasal airway was narrower compared to that located posterior to it. On the contrary, control patients' anterior nasal airway was as large as the posterior one.