What is velopharyngeal insufficiency (VPI)?
In American speech, most letters are produced through the mouth and require no, or very little, air flowing through the nose. In fact, the only consonants produced through the nose are “m,” ”n” and “ng.” The muscles in the roof of the mouth (palate) and the throat work together and close off the nose area from the mouth area to provide the right balance for normal-sounding speech. This is known as velopharyngeal closure.
If there’s a problem with this closure, air escapes through the nose instead of the mouth. This is known as VPI, or velopharyngeal insufficiency, and it affects the quality of a child’s speech.
Having a cleft palate contributes to VPI and it is not uncommon for a child with a cleft palate to have speech issues related to VPI. Surgery to close the palate can help speech sound normal, but about 20 percent of children with a cleft palate may still have VPI after the repair surgery.
What causes VPI?
The physical problems that can affect the closure between the mouth and nose areas include:
- Poor movement of the palate
- A palate that is not long enough to reach the back wall of the throat
- An open cleft palate (a cleft palate that has not yet been repaired or has a fistula, or small hole in it, after the repair)
- A submucous cleft palate (a condition where the muscles of the palate are not joined together properly)
What does VPI sound like?
A person with VPI will have speech that has a nasal sound to it. This is called hypernasality when too much air escapes through the nose.
How is VPI diagnosed?
It is very important that a speech-language pathologist who is part of a craniofacial team evaluate a child’s speech to identify velopharyngeal insufficiency. There are other speech problems that may exist along with or instead of VPI. Special tests may be recommended to determine the specific cause of the speech problem.
A child can be referred to our VPI clinic. As part of the evaluation process, our team’s ear, nose and throat doctor works with our speech-language pathologist and craniofacial plastic surgeon to perform a procedure called nasendoscopy. A small flexible fiberoptic scope is inserted into the child’s nose. This allows them to see how the muscles in the throat are working while a child is talking. The image helps the team decide on treatment recommendations.
How is VPI treated?
Our VPI team will review what is found on the test and talk with the family about the best approach to correct VPI. These approaches may include:
- Surgery: The size and shape of your child's velopharyngeal gap will dictate the type of surgery that is necessary. The most common types of surgery for VPI are a posterior pharyngeal wall injection augmentation, furlow palatoplasty, pharyngeal flap or sphincter pharyngoplasty.
- Speech therapy
- Use of a special mouth appliance to help the palate move in a way to obtain better speech
Other speech problems may exist or develop related to VPI and often affect the way a child produces their speech sounds (articulation). Children may try to make up for their VPI and in doing so they may develop unusual speech patterns called compensatory substitutions. These patterns can quickly become habits and are difficult to change if not corrected early by speech therapy. A therapy program should be started as soon as possible, even before physical correction of VPI, to help minimize the development of these habits.
Children with cleft palate, just like all children, may also have other speech problems not directly related to their clefts. These issues may include other errors in speech sounds, problems with speech timing and coordination, and voice and language disorders. A craniofacial speech-language pathologist can help identify these issues and make appropriate recommendations for therapy and further evaluation.