What is velopharyngeal insufficiency?

Velopharyngeal insufficiency is a disorder resulting in the improper closing of the velopharyngeal sphincter (soft palate muscle in the mouth) during speech, allowing air to escape through the nose instead of the mouth. During speech, the velopharyngeal sphincter must close off the nose to properly pronounce strong consonants such as "p," "b," "g," "t" and "d." To close off the nose from the mouth during speech, several structures come together to achieve velopharyngeal closure. These include the velum (soft palate or roof of the mouth), the lateral pharyngeal walls (side walls of the throat) and the posterior pharyngeal wall (the back wall of the throat). If the velopharynx is not closed, snort sounds may be produced through the nose. Improper function of this structure also produces a nasal tone in the voice. Surgery can consist of doing a sphincter pharyngoplasty, where the surgeon moves tissue from the back of the throat closer to the back of the palate. Most times this surgery is recommended when the surgeon decides that the palate is working as well as it can, but the back of the throat isn't moving correctly.