| Velopharyngeal inadequacy | |
|---|---|
| Other names | VPI |
| Specialty | Oral and maxillofacial surgery  |
Velopharyngeal inadequacy is a malfunction of a velopharyngeal mechanism which is responsible for directing the transmission of sound energy and air pressure in both the oral cavity and the nasal cavity. When this mechanism is impaired in some way, the valve does not fully close, and a condition known as "velopharyngeal inadequacy" can develop. VPI can either be congenital or acquired later in life.
A cleft palate is one of the most common causes of VPI. Cleft palate is an anatomical abnormality that occurs in utero and is present at birth. This malformation can affect the lip and palate, or the palate only. A cleft palate can affect the mobility of the velopharyngeal valve, thereby resulting in VPI.[ citation needed ]
While cleft is the most common cause of VPI, other significant etiologies exist. These other causes are outlined in the chart below:
The most frequent types of cleft palates are overt, submucous, and occult submucous.[ citation needed ]
A common method to treat Velopharyngeal insufficiency is pharyngeal flap surgery, where tissue from the back of the mouth is used to close part of the gap. Other ways of treating velopharyngeal insufficiency is by placing a posterior nasopharyngeal wall implant (commonly cartilage or collagen) or type of soft palate lengthening procedure (i.e. VY palatoplasty).[ citation needed ]
Velopharyngeal insufficiency or incompetency are related labels for this phenomenon, in addition to most common generic- velopharyngealinadequacy. Velopharyngeal insufficiency is the inability of the velopharyngeal sphincter to sufficiently separate the nasal cavity from the oral cavity during speech. Velopharyngeal incompetency occurs when the soft palate and the lateral/posterior pharyngeal walls fail to separate the oral cavity from the nasal cavity during speech. Although the definitions are similar, the etiologies correlated with each term differ slightly. However, in the field of medical professionals these terms are typically used interchangeably.[ citation needed ]
The field of articulatory phonetics is a subfield of phonetics that studies articulation and ways that humans produce speech. Articulatory phoneticians explain how humans produce speech sounds via the interaction of different physiological structures. Generally, articulatory phonetics is concerned with the transformation of aerodynamic energy into acoustic energy. Aerodynamic energy refers to the airflow through the vocal tract. Its potential form is air pressure; its kinetic form is the actual dynamic airflow. Acoustic energy is variation in the air pressure that can be represented as sound waves, which are then perceived by the human auditory system as sound.
The uvula, also known as the palatine uvula or staphyle, is a conic projection from the back edge of the middle of the soft palate, composed of connective tissue containing a number of racemose glands, and some muscular fibers. It also contains many serous glands, which produce thin saliva. It is only found in humans.
A cleft lip contains an opening in the upper lip that may extend into the nose. The opening may be on one side, both sides, or in the middle. A cleft palate occurs when the palate contains an opening into the nose. The term orofacial cleft refers to either condition or to both occurring together. These disorders can result in feeding problems, speech problems, hearing problems, and frequent ear infections. Less than half the time the condition is associated with other disorders.
The soft palate is, in mammals, the soft tissue constituting the back of the roof of the mouth. The soft palate is part of the palate of the mouth; the other part is the hard palate. The soft palate is distinguished from the hard palate at the front of the mouth in that it does not contain bone.
A palatal lift prosthesis is a prosthesis that addresses a condition referred to as palatopharyngeal incompetence. Palatopharyngeal incompetence broadly refers to a muscular inability to sufficiently close the port between the nasopharynx and oropharynx during speech and/or swallowing. An inability to adequately close the palatopharyngeal port during speech results in hypernasalance that, depending upon its severity, can render speakers difficult to understand or unintelligible. The potential for compromised intelligibility secondary to hypernasalance is underscored when consideration is given to the fact that only three English language phonemes – /m/, /n/, and /ng/ – are pronounced with an open palatopharyngeal port. Furthermore, an impaired ability to effect a closure of the palatopharyngeal port while swallowing can result in the nasopharyngeal regurgitation of liquid or solid boluses.
Cleft lip and/or palate is a congenital abnormality that is seen frequently around the world. On average, about 1 in every 500-750 live births result in a cleft. Furthermore, in the U.S., the prevalence for cleft lip with or without cleft palate is 2.2 to 11.7 per 10,000 births. Cleft palate alone (CP) results in a prevalence rate of 5.5 to 6.6 per 10,000 births. Cleft of the lip, palate, or both is one of the most common congenital abnormalities and has a birth prevalence rate ranging from 1/1000 to 2.69/1000 amongst different parts of the world.
Hearing loss with craniofacial syndromes is a common occurrence. Many of these multianomaly disorders involve structural malformations of the outer or middle ear, making a significant hearing loss highly likely.
Augmentation pharyngoplasty is a kind of plastic surgery for the pharynx when the tissue at the back of the mouth is not able to close properly. It is typically used to correct speech problems in children with cleft palate. It may also be used to correct problems from a tonsillectomy or because of degenerative diseases. After the surgery, patients have an easier time pronouncing certain sounds, such as 'p' and 't', and the voice may have a less nasal sound.
Vomer flap surgery was used prior to 1975 as a surgical treatment for children with cleft palate. In this procedure, the vomer bone was used to reconstruct the palate and cover the cleft.
A palatal obturator is a prosthesis that totally occludes an opening such as an oronasal fistula. They are similar to dental retainers, but without the front wire. Palatal obturators are typically short-term prosthetics used to close defects of the hard/soft palate that may affect speech production or cause nasal regurgitation during feeding. Following surgery, there may remain a residual orinasal opening on the palate, alveolar ridge, or vestibule of the larynx. A palatal obturator may be used to compensate for hypernasality and to aid in speech therapy targeting correction of compensatory articulation caused by the cleft palate. In simpler terms, a palatal obturator covers any fistulas in the roof of the mouth that lead to the nasal cavity, providing the wearer with a plastic/acrylic, removable roof of the mouth, which aids in speech, eating, and proper air flow.
Pharyngeal flap surgery is a procedure to correct the airflow during speech. The procedure is common among people with cleft palate and some types of dysarthria.
Velopharyngeal insufficiency is a disorder of structure that causes a failure of the velum to close against the posterior pharyngeal wall during speech in order to close off the nasal cavity during oral speech production. This is important because speech requires sound from the vocal folds and airflow from the lungs to be directed into the oral cavity (mouth) for the production of all speech sounds, with the exception of nasal consonants. If complete closure does not occur during speech, this can cause hypernasality and/or audible nasal emission during speech. In addition, there may be inadequate airflow to produce most consonants, making them sound weak or omitted.
Oral and maxillofacial pathology refers to the diseases of the mouth, jaws and related structures such as salivary glands, temporomandibular joints, facial muscles and perioral skin. The mouth is an important organ with many different functions. It is also prone to a variety of medical and dental disorders.
Nasal emission is the abnormal passing of oral air through a cleft palate, or from some other type of velopharyngeal inadequacy (VPI), during the production of a consonant that requires a buildup of oral air pressure for proper pronunciation, such as /p/ or /s/. The escaping air tends to reduce the oral air pressure and impede the proper production of the consonant. Secondary effects sometimes noted with nasal emission are the development of improper compensatory pronunciation habits, including using a very soft voice that uses less breath pressure. Nasal emission can be detected by a number of simple techniques, such as looking for the fogging of a mirror held under the nares or measured more definitively by means of a nasal pneumotachograph
The pharynx is the part of the throat behind the mouth and nasal cavity, and above the esophagus and trachea. It is found in vertebrates and invertebrates, though its structure varies across species. The pharynx carries food to the esophagus and air to the larynx. The flap of cartilage called the epiglottis stops food from entering the larynx.
Oligodactyly is the presence of fewer than five digits on a hand or foot.
Hypernasal speech is a disorder that causes abnormal resonance in a human's voice due to increased airflow through the nose during speech. It is caused by an open nasal cavity resulting from an incomplete closure of the soft palate and/or velopharyngeal sphincter. In normal speech, nasality is referred to as nasalization and is a linguistic category that can apply to vowels or consonants in a specific language. The primary underlying physical variable determining the degree of nasality in normal speech is the opening and closing of a velopharyngeal passageway between the oral vocal tract and the nasal vocal tract. In the normal vocal tract anatomy, this opening is controlled by lowering and raising the velum or soft palate, to open or close, respectively, the velopharyngeal passageway.
The velopharyngeal fricatives, also known as the posterior nasal fricatives, are a family of sounds sound produced by some children with speech disorders, including some with a cleft palate, as a substitute for sibilants, which cannot be produced with a cleft palate. It results from "the approximation but inadequate closure of the upper border of the velum and the posterior pharyngeal wall." To produce a velopharyngeal fricative, the soft palate approaches the pharyngeal wall and narrows the velopharyngeal port, such that the restricted port creates fricative turbulence in air forced through it into the nasal cavity. The articulation may be aided by a posterior positioning of the tongue and may involve velar flutter.
Cleft lip and clip palate is an "umbrella term" for a heterogeneous collection of orofacial clefts. It includes clefting of the upper lip, the maxillary alveolus, and the hard or soft palate, in various combinations. The anatomic combinations include:
The velopharyngeal port or velopharyngeal sphincter is the passage between the nasopharynx and the oropharynx. It is closed off by the soft palate and uvula against the rear pharyngeal wall during swallowing to prevent food and water from entering the nasal passages. During speech, it is open for nasal sounds and closed for oral sounds. It is affected by cleft palate, resulting in velopharyngeal consonants.