General Medical Information

Nasal Valve

Thomas V. Mccaffrey

The nasal valve is the region of the nasal airway extending from the caudal end of the upper lateral cartilage to the anterior end of the interior turbinate. It is located approximately 1.3 cm from the nares. This is the narrowest segment of the nasal airway and is the major flow-resistive segment of the nasal airway. Measurements made from casts of the nasal airway give an average cross-sectional area of 0.73 cm2 for this region. In a normal nose, the nasal valve region is the narrowest segment of the nasal airway. As air enters this constricted segment of the airway, airflow accelerates, and intraluminal pressure decreases according to the Bernoulli principle. This decrease in pressure can collapse this segment of the airway during inspiration if the upper lateral cartilage is anatomically weak or has been surgically detached from the septal cartilage. The erectile tissues of the nasal septum and tip of the inferior turbinate impinge on the nasal valve. Engorgement of these tissues can increase the resistance of this segment of the nasal airway.