General Medical Information

Nasal Vestibule

Thomas V. Mccaffrey

The nasal vestibule is the skin-lined region beginning anteriorly at the nares and extending to the level of the caudal end of the upper lateral cartilage. The support of the vestibule is the alar cartilage and its muscular and fibrous attachments. The nasal alae are subject to pressure changes during the cycle of respiration. During inspiration there is relatively negative pressure within the vestibule. Because of the lack of rigid support of the ala during inspiration, internal negative pressure tends to collapse this segment of the airway. This tendency is normally largely overcome with activation of the dilator nares muscles during inspiration. These muscles are innervated by the facial nerve and normally contract just before the onset of active inspiration. With increased ventilation produced by exercise, activity of the dilator nares muscle increases to prevent an increase in resistance of this segment of the airway.