Fig. 3From: CT comparison of the nasal airway anterior and posterior to the piriform aperture in patients with and without nasal obstructionSegmentation of the CT-CSA. (a) Design of the CT-CSAant−60 in a 40-year-old man, by drawing a line (white line) between the anterior nasal spine and the anterior edge of the intranasal suture in the midsagittal plane. (b) Outlining the nasal airway by drawing a line (white continuous line) at the border between the black space and the grey areaBack to article page