VPI and consequences

What is VPI and what are the consequences of by children with a cleft?

The normal velopharyngeal function works when the nasal cavity is successfully closed off from the oral cavity during speech. This closure is achieved because of structures as the velum and the pharyngeal walls. The velopharyngeal insufficiency (VPI) happens when the velum cannot make this closure, not causing the separation between the two cavities referring from anatomical or structural defects such as cleft palate or submucous cleft palate. (Jones, 2008).

The most important compensatory articulation mechanisms when there is VPI are:

• Glottal stops: forced adduction of the vocal cords, replacing an occlusive sound.
• Pharyngeal fricative: friction in the pharyngeal level replacing fricative and affricate sounds.

Children with VPI have:

• Hypernasality: there is too much sound in the nasal cavity during speech.
• Nasal air emission: there is an audible emission of air stream through the nose during speech production.
• Unclear and weak consonants:  the nasal air emission reduces the oral pressure, making the consonants become weak.
• Dysphonia: this happens because of the glottal stops used as a compensatory articulation production.
• Other voice disorders

Research by Partin (2001) supports that 20% to 30% of children with cleft palate (with or without cleft lip) will have persisting VPI after their palate repair because the palate can remain too short or cannot move successfully. That is why children will need speech therapy sessions after the surgery to treat the abnormalities from their speech caused by VPI. Depending on the type and the severity of the cleft the velopharyngeal insufficiency have different impact on their speech.