Velopharyngeal Insufficiency 

Updated: Apr 17, 2019
Author: Michael J Biavati, MD, FACS, FAAP; Chief Editor: Arlen D Meyers, MD, MBA 

Overview

Background

The activities of swallowing and speaking depend upon the ability to obtain adequate closure of the velopharyngeal port. Both are complex motor skills that involve the coordination of a diverse group of muscles along the upper aerodigestive tract. Velopharyngeal movements during phonation are quite distinct from those involved in swallowing, as is clinically evident in patients who are able to obtain good closure during swallowing yet are unable to obtain adequate closure when speaking.

Phonation involves the generation of a column of air pressure passing from the subglottis into the upper airway. Inadequate velopharyngeal closure (VPC) allows air to escape through the nose during the generation of consonants requiring high oral pressure, leading to inappropriate nasal resonance during speech production. Pharyngeal closure patterns are shown below.

Pharyngeal closure patterns important in velophary Pharyngeal closure patterns important in velopharyngeal insufficiency. (A) Coronal. (B) Sagittal. (C) Circular. (D) Circular with the Passavant ridge.

Causes of hypernasality and velopharyngeal dysfunction (VPD) are many and range from structural causes (eg, cleft palate) to neuromuscular problems (eg, those observed in velocardiofacial [VCF] syndrome). Functional etiologies also exist, including splinting of the palate after tonsillectomy, imitation of cultural or familial role models, and phoneme-specific problems.

Problem

Velopharyngeal closure (VPC) is an important part of speech. All phonemes in the English language with the exception of 3 (/m/, /n/, /ng/) are produced with oral airflow, meaning that the velopharynx should be closed. The nasal phonemes (/m/, /n/, /ng/) are produced with nasal resonance, requiring that the velopharynx be open during their production. With so many phonemes in English requiring oral airflow, oral resonance is important to production of intelligible speech.

In describing the problem of hypernasal speech, differentiation between velopharyngeal mislearning, velopharyngeal incompetency, and velopharyngeal insufficiency (VPI) is important. Velopharyngeal mislearning is best described as incorrect closure of the velopharyngeal port in the nasopharynx as a result of articulation difficulties. Velopharyngeal incompetency is inadequate VPC secondary to a functional problem due to oral motor difficulties (eg, paresis, apraxia, dysarthria).

VPI, in contrast, is inadequate closure of the velopharyngeal port resulting from a structural problem with the velum (eg, submucous cleft palate, shorted velum relative to the depth of the posterior pharyngeal wall, overt cleft palate). The effect of velopharyngeal incompetency or VPI on the patient's speech is usually the same; therefore, these 2 terms typically are used interchangeably or best referred to in general as velopharyngeal dysfunction (VPD).

Etiology

When describing etiologies of velopharyngeal dysfunction (VPD), categories of classification include structural abnormalities of the palate, dynamic impairment of a structurally normal palate, and functional abnormalities unassociated with anatomic or dynamic palatal defects. An overview of common etiologies follows.

Overt cleft palate, either before or after repair, is by far the most common cause of VPD. This condition occurs in approximately 1 of 2000 live births. VPD has been reported in as many as 30-50% of patients following palate repair. A retrospective cohort study by Smyth and Wu found that of 271 nonsyndromic infants who underwent a cleft palate repair involving levator veli palatini muscle repositioning with or without lateral palatal release, fistulae occurred in 28 patients (10.3%) followed up at age 5 years. The investigators also found that the existence of fistulae led to a three-fold increase in VPI, with the VPI rate rising from 18% to 54%. The rate reached 71% when fistulae complicated bilateral cleft lip and palate repair.[1]

A submucous cleft palate is defined by the presence of a bifid or double uvula, muscular diastasis of the soft palate (zona pellucida), and notching of the posterior border of the hard palate. This is usually evident on examination of the oral cavity, especially with elevation of the palate when pronouncing the phoneme /ah/.

By contrast, an occult submucosal cleft palate is an absence or deficiency of the musculus uvulae with a diastasis of the levator veli palatini but without the presence of a bifid uvula or grooving of the oral surface of the soft palate. An occult submucous cleft is best visualized endoscopically as midline notch on the nasal surface of the soft palate during palate elevation.

Most patients with either overt or occult submucous cleft palate can produce normal speech. However, because of their abnormal musculature, these patients may be predisposed to VPD from any changes to the velopharyngeal anatomy, such as adenoidectomy.

Transient VPD with hypernasal resonance following adenoidectomy, with or without tonsillectomy, is not uncommon. This condition may persist for several days to weeks and usually resolves spontaneously. Some nasal regurgitation of liquids may be present during this period. Incidence of persistent VPD after adenoidectomy has been reported to range from 1 per 1,500 to 1 per 10,000 patients. While the adenoid pad is not necessary for normal VPC, it may assist in closure in children with structural or functional abnormalities of the soft palate. Children at risk of developing persistent VPD after adenoidectomy often can be identified preoperatively by presence of repaired cleft palate, submucous cleft palate, palatopharyngeal disproportion (ie, abnormally deep pharynx), or palatal hypotonia.

A predisposition to VPD is also present in patients with trisomy 21 (ie, Down syndrome). The combination of oromotor and developmental delays, generalized hypotonia, and intellectual delays constitute significant risk factors for development of VPD following adenoidectomy. Because patients with trisomy 21 often have a narrow velopharynx and a shallower skull base, resulting in less distance for the palate to traverse to effect closure, this risk is somewhat balanced.

Velocardiofacial syndrome (VCF) is an autosomal dominant entity linked to microdeletions in the long arm of chromosome 22. Major findings include cleft palate (overt, submucous, or occult submucous), conotruncal heart anomalies, mental disabilities, and a characteristic facies. VPD is common in patients with VCF syndrome due to the presence of a cleft palate and pharyngeal hypotonia.

Another syndrome in which VPD is a common feature is Kabuki syndrome (KS). Many findings of KS are similar to those of VCF syndrome, including cleft palate, cardiac abnormalities (typically coarctation of the aorta), muscular hypotonia, and characteristic facial features. As with VCF syndrome, poor muscular tone of the velopharynx is a major cause of VPD in patients with KS.

Velopharyngeal incompetency or VPI also may be a feature of other syndromes (eg, neurofibromatosis, myotonic dystrophy, or any syndrome in which low muscle tone is a feature).

VPD may be caused by tonsil hypertrophy that prevents the palate from adequately moving superiorly during attempted velopharyngeal closure. Tonsillectomy may be appropriate in these patients.

Acquired VPD may present in persons affected by stroke or head injury, especially if damage occurs to motor centers controlling cranial nerves responsible for pharyngeal muscle control. Other neurologic diseases (eg, muscular dystrophy, multiple sclerosis, amyotrophic lateral sclerosis [ALS], Parkinson disease) also may lead to VPD in the more advanced stages of disease. Articulation problems and VPD are especially common in patients undergoing pallidotomy for severe Parkinson disease.

Pathophysiology

Oral resonance (as contrasted to nasal resonance) is obtained by velopharyngeal closure (VPC), a seal between the nasopharynx and the oral cavity. Typically VPC is accomplished by elevation of the velum and approximation of the lateral walls to close off the nasopharynx. In a small group of patients, formation of a Passavant ridge on the posterior pharyngeal wall may contribute to closure. Velopharyngeal dysfunction (VPD) describes what happens when velopharyngeal closure is impaired.

Effects of VPD on a patient's speech include: hypernasality; decreased speech intelligibility; and nasal emissions (ie, air escape out of the nose during speech). How severely a patient's speech is affected depends on several factors, including the following: the amount of gap with a closed velum; the patient's articulation and oral motor ability; and compensatory strategies the patient may have developed to decrease nasal emission or hypernasality.

Common compensatory strategies include: speaking with soft intensity (ie, volume) to decrease airflow through the nasal cavity; speaking with loud intensity or pushing to try to project the voice; and substituting phonemes that require less airflow for the correct phoneme.

Presentation

Historical factors in velopharyngeal dysfunction (VPD) are related primarily to problems with speech intelligibility. The voice is described as having a nasal resonance, and nasal emissions (ie, air escape through the nasal passage with speech) also may be present. Often, compensatory articulation errors are present, worsening speech intelligibility. Hoarseness also commonly is observed in children with VPD due to vocal strain to overcome nasal escape.

Nasal regurgitation, especially in infants, may be a precursor to VPD. Parents may describe a history of food and liquids coming through the nose with feeding and spitting up. In older children and adults, recurrent and chronic sinus infections may be a sign of nasopharyngeal reflux and repeated contamination of the nasal cavity. Persistent otorrhea with ear grommets in place also may be due to nasopharyngeal reflux extending up the Eustachian tube and through the middle ear. A history of recurrent ear infections or persistent middle ear effusions may also be an indicator of poor palatal function.

When eliciting a history from patients with VPD, looking for other factors that may lead to diagnosis of a congenital syndrome is important. Poor feeding and hypotonia in infancy may suggest the presence of a neuromuscular disorder. Congenital heart defects in association with VPD are common features of both velocardiofacial syndrome (VCF) and Kabuki syndrome (KS). A family history may reveal other affected individuals, also pointing to a genetic etiology.

Relevant Anatomy

Six muscles comprise the velopharyngeal sphincter, as follows:

  • Tensor veli palatini: This muscle arises from the scaphoid fossa, spine of the sphenoid, and the cartilaginous portion of the eustachian tube. It inserts into a tendon winding around the hamular process. Innervated by the mandibular branch of cranial nerve (CN) V, it tenses the soft palate and opens the eustachian tube during swallowing.

  • Levator veli palatini: This muscle arises from the petrous apex and cartilaginous portion of the eustachian tube. Its fibers fan out in the soft palate and blend with the contralateral levator. Innervated by the pharyngeal plexus from CN IX and X, it pulls the velum in a posterosuperior direction and serves as the major elevator for the velum.

  • Musculus uvulae: This muscle arises from the palatal aponeurosis posterior to the hard palate and inserts into the uvula mucosa. Innervated by the pharyngeal plexus, it functions to add bulk to the dorsal aspect of the uvula.

  • Palatoglossus: The palatoglossus arises from the anterior surface of the soft palate and inserts into the lateral aspect of the tongue base. Innervated by the pharyngeal plexus, it simultaneously lowers the velum and elevates the tongue upwards and backwards.

  • Palatopharyngeus: The palatopharyngeus arises from the soft palate and inserts into the posterior border of the thyroid cartilage. Innervated by the pharyngeal plexus, it positions the velum and narrows the velopharyngeal orifice by adducting the posterior pillars and constricting the pharyngeal isthmus. This muscle also raises the larynx and lowers the pharynx.

  • Superior constrictor: This muscle arises from the lower portion of the pterygoid plate and the hamular process and inserts into the median raphe. Innervated by the pharyngeal plexus, it produces medial movement of the pharyngeal walls and assists in drawing the velum posteriorly.

When viewed endoscopically, several topical anatomic features of the velopharynx (nasopharynx) are important to note.

  • Pharyngeal ostium of the eustachian (auditory) tube: This opening and its associated structures comprise the lateral wall of the nasopharynx. The ostium is bordered anteriorly by the salpingopalatine fold and posteriorly by the cartilaginous torus tubarius. Posterior to the torus tubarius is the pharyngeal recess. Extending inferiorly from the torus tubarius is the salpingopharyngeal fold, which overlies the salpingopharyngeal muscle. Inferior to the ostium and torus, the pterygopharyngeal portion of the superior pharyngeal constrictor muscle comprises the lateral wall of the nasopharynx.

  • Pharyngeal tonsil (ie, adenoid): The adenoid, which is a closely aggregated collection of lymphoid nodules, is directly posterior in the nasopharynx and overlies the basilar portions of the sphenoid and occipital bones. The adenoid lies directly between the torus tubarius on either side and may extend laterally into the pharyngeal recess, where it is commonly known as the eustachian or Gerlach tonsil. Superiorly, the adenoid may extend up into the nasal choanae, and inferiorly, it ends at or near the level of the anterior arch of the atlas. The prevertebral fascia and the atlanto-occipital membrane lie deep to the pharyngeal tonsil.

  • Posterior pharyngeal wall: Immediately inferior to the pharyngeal tonsil, the posterior pharyngeal wall comprises mainly the superior pharyngeal constrictor muscle. Contraction of this muscle in the axial plane at the level of VPC constitutes a structure known as the Passavant ridge.

  • Pharyngeal surface of the soft palate: This structure is formed by the aponeuroses of several muscles including the superior pharyngeal constrictor muscle, levator veli palatini muscle, salpingopharyngeus muscle, palatopharyngeus muscle, and uvular muscle. The insertion and innervation of these muscles is described above.

Contraindications

One factor to consider in preoperative planning is whether breathing is obstructed preoperatively. Placement of a pharyngeal flap increases the degree of nasal airway obstruction and may worsen any preexisting obstructive sleep apnea. This is especially true in patients with Pierre Robin syndrome, in which retrognathia may result in upper airway obstruction. In such instances, consideration should be given to pharyngoplasty instead of pharyngeal flap, since the risk of worsening airway obstruction postoperatively is lessened with pharyngoplasty.

The location of the internal carotid arteries as they traverse the lateral pharynx is also an important consideration, especially in patients with velocardiofacial syndrome (VCF). In patients with VCF, the internal carotid artery can take a more medial position, with a theoretical risk of injury to the ICA during pharyngeal surgery. Preoperative evaluation with contrast-enhanced CT scan or magnetic resonance angiography can elucidate the course of the ICA. In practice, the ICA will lateralize when the head is extended for surgery and will not be in the operative field during pharyngoplasty or pharyngeal flap surgery, and the presence of a medially displaced ICA is not necessarily a surgical contraindication.

The presence of a primary bleeding disorder (ie, hemophilia or von Willebrand disease) may complicate surgical management. Likewise, anticoagulation for reasons such as a prosthetic heart valve may be a contraindication to surgery.

 

Workup

Diagnostic Procedures

Voice and resonance evaluation: A voice and resonance evaluation completed by a speech/language pathologist (SLP) can provide informative data in determining the appropriate course of treatment of velopharyngeal dysfunction (VPD). A thorough voice and resonance evaluation for VPD includes articulation assessment, oral motor assessment, and measurement of nasal airflow.

  • Articulation assessment: Measures of articulation ability, such as the Articulation Proficiency Scale, are administered at the single-word level to determine articulation errors. The patient's speech intelligibility is rated based on this scale and characterized as mild, moderate, or severe. Types of articulation errors also are described, including distortions such as nasal emissions, glottal stops, or nasal fricatives. The patient's response to correction of articulation errors, distortions, nasal emissions, and hypernasality also is assessed in order to determine prognosis for improvement with speech therapy.

  • Oral motor assessment: A subjective oral motor assessment is completed by observing range of motion and speed of the lips and tongue and observing the soft palate and velar elevation when pronouncing the phoneme /ah/. Overall facial symmetry and muscle tone also are noted.

  • Measurement of nasal airflow: The MacKay-Kummer Simplified Nasometric Assessment Procedures (SNAP) test is administered to children aged 3-9 years with Pentax Medical's Nasometer to assess the ratio of oral airflow to nasal airflow. For children aged 9 years and older and for adults, the Zoo Passage, Rainbow Passage, and Nasal Sentences are substituted as standard reading passages. Nasometer results are compared to normative data. A score 3 standard deviations above the mean indicates hypernasal resonance, i.e., speaking with too much airflow and resonance in the nasal cavity. A score 3 standard deviations below the mean indicates hyponasality, which is defined as insufficient nasal resonance for the nasal phonemes (ie, /m/, /n/, /ng/).

Cephalometry can be used to delineate factors such as C1 vertebral abnormalities, excessive pharyngeal depth, and short velum that contribute to VPD in VCF syndrome.[2]

Fiberoptic nasoendoscopy: Following voice evaluation, a determination of the need for fiberoptic nasoendoscopy (FN) is made based on the test results. Indications for FN include hypernasality (either consistent or inconsistent), poor oral airflow with nasal escape, and structural abnormalities of the soft palate. If none of these conditions exist and the patient presents with sufficient oral airflow for most phonemes, speech therapy typically is recommended with periodic reevaluation prior to completion of nasoendoscopy.

  • Sedation: Sedation is typically not used for this procedure. In certain instances, children under 5 and older children who are uncooperative sedation may be helpful. Typically oral midazolam (Versed) is administered at a dose of 0.5 mg/kg (up to 10 mg) and given 15-20 minutes prior to FN. This dosage provides adequate amnesia and sedation while allowing the child to perform the necessary tasks for the examination. Higher doses of midazolam may make the examination difficult because the child is sedated too heavily.

  • Topical anesthesia: Prior to placement of the fiberscope, the nasal cavity is examined for any obstructions that may inhibit passage of the scope into the nasopharynx. The nose then is decongested and anesthetized with a mixture of 4% lidocaine and 0.05% oxymetazoline hydrochloride, which is sprayed into the nose with an atomizing device.

  • Procedure: The fiberscope is passed through the nostril, superior to the inferior turbinate, to the posterior nasal choana. Passage of the scope along the floor of the nose does not position the fiberscope high enough to allow for visualization of the entire velopharyngeal sphincter. With the fiberscope in place, the patient is asked to repeat a series of words and sentences loaded with phonemes that require increased oral airflow (eg, plosives, fricatives) in order to observe the velar closure pattern. The examination is videotaped for later review. Patients who are unable to vocalize these phonemes may be grossly assessed by this technique by looking at overall VPC and identifying any deficiency in each of the specific planes of closure.

  • Advantages and disadvantages: Nasoendoscopy is superior to other methods of assessing VPD (ie, videofluoroscopy) in that it allows for direct visualization of the velopharyngeal sphincter. This is especially important in the postsurgical patient when the velopharyngeal anatomy is altered, such as following placement of a pharyngeal flap. As compared with videofluoroscopy, FN is slightly more invasive and requires a moderate degree of cooperation from the child to obtain an adequate examination.

Videofluoroscopy: Videofluoroscopy (VF) is performed by the SLP in conjunction with a radiologist. Unlike nasopharyngoscopy, VF enables the examiner to see through tissues, so that movement can be discerned at all vertical and horizontal planes within the pharynx. A 3-dimensional perspective can be gained using frontal and lateral projections, along with base or Towne projections.

  • Procedure: VF usually is performed without sedation. Barium is instilled through the nose using a nose dropper in order to contrast soft tissues against the surrounding skeletal structures. Fluoroscopic views then are obtained in the lateral, anteroposterior (frontal), and base projections while the patient articulates phonemes that require increased oral airflow. The lateral view helps the examiner visualize the velum, posterior pharyngeal wall, and tongue. The frontal view enables assessment of the lateral pharyngeal walls along the entire vertical extent of the pharynx.

  • Advantages and disadvantages: VF allows more precise localization of the level of VPC by measuring the level against the spine. Observation of the tongue is also important, as the tongue may contribute to closure in a compensatory fashion by lifting the palate, as is seen in swallowing. This information may be missed with nasopharyngoscopy alone. VF has the obvious disadvantage of radiation exposure. In addition, when normal anatomy is altered (eg, postsurgery), interpretation of the images may be difficult.

 

Treatment

Medical Therapy

Speech therapy

Speech therapy improves velopharyngeal function when velopharyngeal dysfunction (VPD) is minimal or due to articulation errors and in postoperative patients. Compensatory articulation techniques secondary to VPD also can be corrected with speech therapy. However, in patients with a specific anatomic deficiency that precludes adequate closure of the velopharynx, speech therapy cannot replace surgery.

Upon completion of speech and language testing, the SLP determines if VPD and hypernasality are related to articulation errors or if the condition is phoneme specific. If either is the case, the VPD usually is not related to structural abnormalities, and correction with speech therapy most likely is possible.

VPD also can be a result of decreased muscle tone in the oral musculature and soft palate. Decreased muscle tone can be observed on fiberoptic nasoendoscopy when the soft palate closes inconsistently or when closure appears slow in connected speech.[3] A period of speech/language therapy focusing on improving overall oral motor skills and improving strength and elevation of the velum may be able to correct VPD in this case.

Visual feedback

In some children, especially those with hearing impairments, visual feedback can assist in therapy to improve VPD. Several devices are available to assist with this method. Simple tools (e.g., cold mirror, paper paddle) can serve to show the patient when nasal escape occurs. Other devices are commercially available, such as the See-Scape, which is placed at the nose and causes a ball to rise when airflow is nasal rather than oral.

A more sophisticated method is the use of a Nasometer, which graphically displays a ratio of oral sound energy to nasal sound energy. The visual readout can help the therapist and patient develop compensatory techniques to reduce nasalance. In older children, videotaped nasopharyngoscopy has been used to achieve the same goals.

Nasal continuous positive airway pressure therapy

Continuous positive airway pressure (CPAP) therapy is beneficial for patients whose VPD seems related to oral motor issues or velar weakness rather than structural problems of the velum. CPAP therapy is a palate-strengthening program using CPAP equipment, including a nasal mask, which is completed 6 days per week for 8 weeks in the patient's home. With the mask in place, the patient repeats a series of consonant-vowel combinations and sentences designed to cause the velum to open and close against air pressure from the nasal mask. CPAP pressures are increased on a regimented schedule, producing exercises similar to a weightlifting program for the soft palate.

CPAP therapy has the disadvantages of being very regimented and requiring cooperation and participation for up to 24 minutes, 6 days per week, which is difficult for young children. Wearing the nasal mask and speaking with nasal air pressure also can be frightening for some young children. Furthermore, this treatment program is still relatively new and needs further research to determine its effectiveness.

Prosthetics

These devices are helpful when surgery is contraindicated, when the cause of VPI is neuromuscular in nature, or as a temporizing measure until surgery can be performed.

Obturators can substitute for tissue deficiency and are attached to the palate or teeth. In certain cases, the obturator can be downsized gradually so that the native tissue, if adequate in bulk, can strengthen over time and compensate for the decreasing obturator size.

Palatal lifts are used when adequate palatal length exists but dynamic motion of the palate is poor due to neuromuscular etiologies. Palatal lifts reduce the distance the palate must traverse to produce adequate closure.[4]

An additional option is a nasal valve, an appliance fitted to each nostril. A one-way valve on either side allows the patient to breathe in through the nose, but stops nasal airflow with exhalation or speech.

Surgical Therapy

As noted previously, the primary indications for surgical intervention include a structural defect of the velum or a functional problem that results in poor or inconsistent velar closure.

Maximum benefit can be achieved when surgical technique takes advantage of whatever native velopharyngeal function exists. Information obtained during objective evaluation via physical examination, nasopharyngoscopy, and/or multiview video fluoroscopy greatly aids in determining how best to accomplish velopharyngeal closure. Determination of a patient's predominant VPC pattern directs the surgeon to the treatment most appropriate for the patient.

Surgical techniques are illustrated in the videos below.

Coronal closure.
Sagittal closure.
Circular closure.
Circular closure with Passavant's ridge.
Patient with severe articulation disorder and velocardiofacial syndrome. Little or no velar closure is noted on nasopharyngoscopy, known as a "black hole." Surgical treatment is with a wide pharyngeal flap. Aberrant carotid arteries coursing through the nasopharynx complicate surgical management.

Preoperative Details

Velopharyngeal closure pattern

Several patterns of VPC have been described based on nasoendoscopy and VF examinations. The type of closure pattern is determined by the relative contribution of the palate and lateral pharyngeal walls to closure of the velopharyngeal sphincter.

Four basic types of closure patterns, coronal, circular, circular with the Passavant ridge, and sagittal, are used to describe velar closure as seen in the image below. Defining the type of closure pattern is important when considering surgical intervention for correction of VPD.

Pharyngeal closure patterns important in velophary Pharyngeal closure patterns important in velopharyngeal insufficiency. (A) Coronal. (B) Sagittal. (C) Circular. (D) Circular with the Passavant ridge.

See the list below:

  • Coronal: The most common closure pattern, coronal closure is present in 55% of patients with normal velar function. The major contribution to closure is from the soft palate as it contacts a broad area of the posterior pharyngeal wall. Little medial motion of the lateral pharyngeal walls occurs. A coronal closure pattern is often present with an enlarged adenoid pad.

  • Circular: Present in approximately 20% of individuals with normal closure, circular closure involves contribution from both the soft palate and the lateral pharyngeal walls. This results in a closure that resembles a circle getting smaller.

  • Circular with the Passavant ridge: This closure pattern occurs in 15-20% of the population and is a circular pattern that involves anterior motion of the posterior pharyngeal wall (known as Passavant's ridge).

  • Sagittal: The least common pattern, sagittal closure is prevalent in 10-15% of people. Here, palatal elevation is minimal. The main contribution is from medial motion of the lateral pharyngeal walls. This is the pattern seen most commonly in patients with persistent VPD following repair of a cleft palate.

Determination of a patient's closure pattern is clinically significant, as is the determination of the vertical level of closure. The type of closure pattern determines the type of surgical intervention, because surgical intervention is most effective when it targets the point of maximal pharyngeal motion.

Tonsillectomy and adenoidectomy

Another preoperative consideration is the need for adenoidectomy and/or tonsillectomy. In most instances, preoperative adenoidectomy is necessary for either pharyngoplasty or pharyngeal flap. Indications for preoperative tonsillectomy vary.

In the case of pharyngoplasty, adenoidectomy makes room for placement of the lateral pharyngeal wall flaps. Failure to remove the adenoid makes attachment of the flaps to the posterior pharyngeal wall difficult. The need for tonsillectomy before pharyngoplasty is determined by the degree of obstruction. This determination is somewhat subjective and based on the size of the tonsils and whether they interfere with the raising of the lateral pharyngeal wall flaps. Leaving the tonsils in place often helps preserve the posterior tonsillar pilars, which are used to create the pharyngoplasty flaps.

With pharyngeal flaps, removing both the tonsils and adenoid often is necessary. Placement of a pharyngeal flap makes subsequent adenoidectomy difficult if not impossible, and residual adenoid tissue may obstruct the lateral pharyngeal ports. Similarly, the tonsils may obstruct the pharyngeal ports from below, so their removal typically is recommended.

Other considerations

One factor to consider in preoperative planning is whether breathing is obstructed preoperatively. Placement of a pharyngeal flap increases the degree of nasal airway obstruction and may worsen any preexisting obstructive sleep apnea. This is especially true in patients with Pierre Robin syndrome, in which retrognathia may result in upper airway obstruction. In such instances, consideration should be given to pharyngoplasty instead of pharyngeal flap, since the risk of worsening airway obstruction postoperatively is lessened with pharyngoplasty.

The location of the internal carotid arteries as they traverse the lateral pharynx is also an important consideration, especially in patients with velocardiofacial syndrome. In patients with VCF syndrome, the carotid artery can take a more medial position, placing it at risk of injury during pharyngeal surgery. Preoperative evaluation with contrast-enhanced CT scan or magnetic resonance angiography can settle this issue.

Intraoperative Details

Following is an overview of the 3 main surgical approaches to velopharyngeal corrective surgery, which are pharyngoplasty, pharyngeal flap, and posterior pharyngeal wall augmentation.

Pharyngoplasty

This approach is advantageous when coronal or circular closure is present and lateral pharyngeal wall motion is deficient. The goal is to develop a more functional sphincter by improving the dynamics and bulk of the velopharyngeal tissues and by tightening and reducing the size of the velopharyngeal opening.

Hynes was the first to describe pharyngoplasty in 1950 as the elevation of 2 superiorly based flaps comprising the right and left salpingopharyngeus muscles and overlying mucosa. The flaps were rotated 90° and sutured to the mucosal edges of a transverse incision made across the nasopharynx just below the level of the tori tubariae.

In 1968, Orticochea described a modification of the pharyngoplasty procedure using 2 superiorly based flaps comprising the posterior tonsillar pillars with the underlying palatopharyngeus muscles.[5] A small inferiorly based posterior pharyngeal wall flap then was elevated, and the 2 lateral flaps were rotated 90° and inserted onto the posterior flap. Jackson further modified this method by sewing the lateral flaps onto a superiorly based posterior pharyngeal wall flap, allowing higher placement of the lateral wall flaps.

As noted above, the need for adenoidectomy and possible tonsillectomy is determined preoperatively. Adenoidectomy is performed several weeks (minimum 6 weeks) preoperatively to allow for healing of the velopharyngeal sphincter. If the tonsils are significantly enlarged so that they may make raising the palatopharyngeal flaps difficult, they must be removed. Velar closure is then reassessed following adenoidectomy (and tonsillectomy) as the muscular dynamics may have changed.

Other technical considerations include recognizing that more superiorly the palatopharyngeal flaps are elevated, the greater the degree of velopharyngeal obturation. If this is excessive, an obstructive pattern of breathing can develop. Even if the obturation is not excessive, some patients still develop some mild temporary obstructive sleep patterns in the immediate postoperative period. For this reason, most surgeons place a nasal trumpet through the sphincter intraoperatively and remove it the next morning.

Several studies have reported a success rate (ie, correction or significant reduction in hypernasality) from 78-100% with pharyngoplasty. The incidence of postoperative hyponasality is estimated to be 12-17%.

One study reported a 10-year experience on the efficacy of sphincter pharyngoplasty for velopharyngeal insufficiency repair, using need for surgical revision as the primary outcome measure. Six (13%) of 46 patients required revision, achieving a single-procedure success rate of 87%. With a single revision, 100% success was achieved. Further, they reported that compared with sphincter pharyngoplasty alone, Furlow palatoplasty at the same time as sphincter pharyngoplasty may lead to improved outcomes. Further study is needed to clarify this relationship.[6]

Pharyngeal flap

This is the preferred method in patients with good lateral pharyngeal wall motion who have a persistent central gap due to poor palatal motion, as is common following repair of a cleft palate. The procedure aims to develop a central flap of tissue to obturate the midline of the pharyngeal port and decrease the degree of air escape into the nasal cavity.

Schoenborn first reported this procedure in 1876 when he described an inferiorly based posterior wall flap sutured to the nasal surface of the soft palate. He later modified this procedure by using a superiorly based flap when he found that an inferiorly based flap tended to contract and tether the palate downward over time, worsening the patient's VPI.

The flap is raised down to the level of the prevertebral fascia, creating a tissue flap of superior constrictor muscle with its overlying mucosa. This flap is raised superiorly so that its base is at the level of the arch of C1. Typically, splitting the soft palate in the midline is necessary to provide better access to the nasopharynx during creation of the flap. The flap then is sutured to the nasal surface of the palate by incorporating it into the split repair.

Alternatively, the flap can be inset into the palate by performing a fish-mouth incision on its nasal surface. Raising a longer flap than necessary is advantageous to accommodate any future flap contracture. Red rubber nasal trumpets (4 fr) are placed through the resulting lateral ports to alleviate any immediate postoperative obstructive breathing patterns.

One large series of 500 patients reported normalization or resolution of hypernasality in 90% of patients. Failure to improve is related to inadequate flap width either by design or due to contracture. Conversely, a flap that is too wide narrows the lateral ports and produces hyponasal speech. Postoperative airway obstruction is most likely to occur within the first 24 hours and in one series resolved within 2 days in more than 90% of patients.

Posterior wall augmentation

This approach is appropriate in the presence of a persistent gap in the central velopharyngeal port measuring at most 1-3 mm. It also is indicated when the patient can achieve touch closure that is not tight enough to prevent air escape with high oral pressure. Persistent postadenoidectomy VPI is also an appropriate indication for this procedure. Both autogenous tissue and foreign implants have been used for this approach.

A superiorly based pharyngeal flap incorporating the superior constrictor is raised down to the prevertebral fascia. The superior extent of elevation is defined just above the point of maximal closure. It then is buckled onto itself and sutured in place. Initially good results can become less favorable as the flap can atrophy with time, and this procedure is recommended only for small gaps.

A wide variety of implantable materials has been used to augment the posterior wall. Problems with extrusion, migration, resorption, and infection have been reported. Silicone has been noted to have a high extrusion rate. Teflon is not advised for use in the pharynx due to concerns over the risk of injection into large blood vessels. Both silicone and Teflon also have a tendency to migrate inferiorly along the prevertebral fascia. Autologous tissue, such as fat or rolled dermis, has been less problematic but tends to resorb with time.

More recent reports have described the use of calcium hydroxyapatite injected into the posterior pharyngeal wall. This technique has been demonstrated to have a reasonably high success rate with no migration or extrusion of the injected material. Polyethylene implants imbedded into the posterior pharynx has also demonstrated success in some adult patients.

For any of theses procedures, suturing is performed with 3-0 or 4-0 Vicryl sutures because chromic sutures tend not to provide sufficient holding strength and may result in repair dehiscence. Mucosal closure may be performed with chromic sutures as long as closure tension is not too great.

Postoperative Details

Immediate postoperative concerns deal mainly with upper airway obstruction. Placement of nasal trumpets overnight is helpful in management of airway obstruction while the patient is still under the effects of anesthesia. A 2-0 suture placed through the tip of the tongue and used to protrude the tongue can be helpful in temporary airway management in the postanesthesia recovery area.

Patients are admitted overnight primarily for airway management and intravenous hydration. Discharge home is on the first postoperative day as long as oral diet is tolerated and pain control by mouth is adequate.

Pain management postoperatively typically is limited to narcotics such as acetaminophen with either codeine or hydrocodone. Stronger narcotics, such as morphine or meperidine, may cause increased sedation worsening airway obstruction.

Once the patient is tolerating oral fluids and any postoperative nausea has cleared, the patient resumes a diet of thick liquids and soft foods. With pharyngoplasty, a diet similar to that for tonsillectomy patients is used and may include most foods as tolerated. Patients undergoing a pharyngeal flap procedure follow dietary restrictions similar to those for patients undergoing palatoplasty, since the soft palate is divided and repaired. Typically, these patients are restricted to thick liquids or soft foods (eg, mashed potatoes) until the palatal incision has healed (usually 10-14 days).

Follow-up

The initial follow-up appointment is at 7-10 days, at which time the wound is examined for proper healing. A determination regarding resuming a regular diet also is made at this time. Snoring and upper airway obstruction, if present at this point, usually resolve over the next several weeks as edema decreases and flap shrinkage occurs.

At 6 weeks, healing is usually complete, and a speech and resonance reassessment is performed. Surgical correction of structural defects in the velopharyngeal port does not necessarily change function, and articulation problems may persist following surgery. Based on the postsurgical speech and resonance evaluation findings, speech therapy is resumed at this point as necessary.

Complications

Pharyngoplasty

More superiorly raised palatopharyngeal flaps lead to a greater degree of velopharyngeal obturation. If this is excessive, an obstructive pattern of breathing can develop. However, even if the obturation is not excessive, some patients still develop some mild temporary obstructive sleep patterns in the immediate postoperative period. For this reason, most surgeons place a nasal trumpet through the sphincter intraoperatively and remove it the next morning.

Long-term considerations are shrinkage of the flaps and nasopharyngeal scarring. Over time, the flaps may shrink, reducing the bulk of the repair and altering speech results. Patients with return of velopharyngeal escape over time may be a candidate for flap augmentation with fat injection.[7] Nasopharyngeal stenosis may also result, especially if the dissection is carried up onto the soft palate. Resultant upper airway and nasal obstruction may require revision pharyngoplasty with tissue grafts.

Pharyngeal flap

Failure to improve is related to inadequate flap width either by design or due to contracture. Conversely, a flap that is too wide narrows the lateral ports and produces hyponasal speech. Postoperative airway obstruction is most likely to occur within the first 24 hours and in one series resolved within 2 days in more than 90% of patients.

A study by Campos et al indicated that cleft palate repair with a pharyngeal flap may not be associated with obstructive sleep apnea. The study involved 42 middle-aged patients who underwent cleft palate repair, including 22 whose procedure employed a flap and 20 whose repair did not. Although the majority of patients in the study were diagnosed with obstructive sleep apnea, the rate of occurrence did not differ significantly between the flap and nonflap groups (77% and 60%, respectively). The investigators suggested that the occurrence of sleep apnea may have been associated with the patients’ advancing age and with congenital upper airway abnormalities.[8]

Outcome and Prognosis

Pharyngoplasty

Several studies have reported a success rate (ie, correction or significant reduction in hypernasality) between 78-100% with pharyngoplasty. The incidence of postoperative hyponasality is estimated to be 12-17%.

Pharyngeal flap

One large series of 500 patients reported normalization or resolution of hypernasality in 90% of patients.

A literature review by Wagner et al of VPI associated with 22q11.2 deletion syndrome found that treatment with a posterior pharyngeal flap resulted in successful outcomes in 85% of patients.[9]

A retrospective study by Rogers et al of 19 patients with VPI, 18 of whom had a history of cleft palate, found significant speech improvement following surgery using a wide, superiorly based pharyngeal flap.[10]

A retrospective study by Setabutr et al indicated that in patients who undergo pharyngeal flap surgery, older age at the time of surgery is a risk factor for revision. The study, of 61 patients who underwent the pharyngeal flap procedure, found improved speech postoperatively, with the mean nasal air emission score in patients being reduced from 2.0 to 0.8 and the mean resonance being reduced from 2.4 to 0.9. The revision rate was 20% (12 patients), with age being the only covariate found that significantly correlated with a greater chance of revision surgery.[11]

A study by Bohm et al indicated that in patients with velopharyngeal insufficiency (VPI) related to 22q11.2 deletion syndrome, concomitant palatoplasty and sphincter pharyngoplasty produces comparable speech outcomes to pharyngeal flap surgery. The two procedures produced significantly better results than sphincter pharyngoplasty alone, although outcomes from all three operative approaches were similar with regard to complication rates and the need for revision surgery.[12]