You are in: eMedicine Specialties > Otolaryngology and Facial Plastic Surgery > PEDIATRIC OTOLARYNGOLOGY Velopharyngeal InsufficiencyArticle Last Updated: Oct 14, 2006AUTHOR AND EDITOR INFORMATIONAuthor: Michael J Biavati, MD, Clinical Assistant Professor, Department of Otolaryngology, University of Texas Southwestern Michael J Biavati is a member of the following medical societies: American Academy of Otolaryngology-Head and Neck Surgery, American Academy of Pediatrics, American Cleft Palate/Craniofacial Association, American College of Surgeons, American Laryngological Rhinological and Otological Society, American Society of Pediatric Otolaryngology, Society for Ear, Nose and Throat Advances in Children, and Texas Medical Association Coauthor(s): Gina Rocha-Worley, MS, CCC/SLP, Speech Pathologist, Department of Speech Pathology, Harlem Hospital Center Editors: Ari J Goldsmith, MD, Program Director, Associate Professor, Department of Otolaryngology, Division of Pediatric Otolaryngology, State University of New York Downstate Medical Center; Francisco Talavera, PharmD, PhD, Senior Pharmacy Editor, eMedicine; Gregory C Allen, MD, Assistant Professor, Department of Otolaryngology-Head and Neck Surgery, University of Colorado School of Medicine; Christopher L Slack, MD, Otolaryngology-Facial Plastic Surgery, Private Practice, Associated Coastal ENT; Medical Director, Treasure Coast Sleep Disorders; Arlen D Meyers, MD, MBA, Professor, Department of Otolaryngology-Head and Neck Surgery, University of Colorado School of Medicine Author and Editor Disclosure Synonyms and related keywords: velopharyngeal insufficiency, VPI, velopharyngeal incompetency, velopharyngeal dysfunction, VPD, hypernasality, resonance disorders, cleft palate, palatoplasty, pharyngeal flap, pharyngoplasty, velocardiofacial syndrome, VCF syndrome, Kabuki syndrome, KS, Shprintzen syndrome INTRODUCTIONThe 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. 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. ProblemVPC 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 VPD. EtiologyWhen describing etiologies of 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.
PathophysiologyOral resonance (as contrasted to nasal resonance) is obtained by 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. VPD describes what happens when VPC 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 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. ClinicalHistorical factors in 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. 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. 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 VCF syndrome (ie, Shprintzen syndrome) and Kabuki syndrome (KS). A family history may reveal other affected individuals, pointing to a genetic etiology. RELEVANT ANATOMYSix muscles comprise the velopharyngeal sphincter.
When viewed endoscopically, several topical anatomic features of the velopharynx (nasopharynx) are important to note.
CONTRAINDICATIONSOne 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 VCF 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. WORKUPDiagnostic Procedures
TREATMENTMedical therapySpeech therapy Speech therapy improves velopharyngeal function when 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. 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 (eg, 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. Two types of prostheses are available. Obturators can substitute for tissue deficiency and are attached to the teeth by metal wire or bands. 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. Surgical therapyAs 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 in the patient. Information obtained during objective evaluation via physical examination, nasopharyngoscopy, and/or multiview VF greatly aids in determining how best to accomplish this. Determination of a patient's predominant VPC pattern directs the surgeon to the treatment most appropriate for the patient. Preoperative detailsVelopharyngeal 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 (see Image 1). Defining the type of closure pattern is important when considering surgical intervention for correction of VPD.
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 tonsillectomy and/or adenoidectomy. In most instances, preoperative adenoidectomy is necessary. 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 VCF 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 detailsFollowing 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 sphincter. 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. 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 possible tonsillectomy and/or adenoidectomy is determined preoperatively. Adenoidectomy is performed several weeks (minimum 6 wk) preoperatively if the desired vertical level of the sphincter is expected to lie at or above the level of the adenoid pad. Similarly, if the tonsils are significantly enlarged so that they may make raising the palatopharyngeal flaps difficult, they must be removed. Other technical considerations include recognizing that 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. 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%. 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 (4F) 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 banned by the Food and Drug Administration (FDA) due to a high extrusion rate. Teflon is not approved for use in the pharynx due to concerns over the risk of injection into large blood vessels. Autologous tissue, such as fat or rolled dermis, has been less problematic but tends to resorb with time. All 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 detailsImmediate 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 airway management in the postanesthesia recovery room. 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 mild narcotics such as acetaminophen with either codeine or hydrocodone. Stronger narcotics, such as morphine or meperidine, may cause 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 and soft blended foods (eg, mashed potatoes) until the palatal incision has healed (usually 2-3 wk). Follow-upThe initial follow-up appointment is at 7-10 days, at which time the wound is examined for healing problems. 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. COMPLICATIONSPharyngoplasty 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. 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. OUTCOME AND PROGNOSISPharyngoplasty 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 be12-17%. Pharyngeal flap One large series of 500 patients reported normalization or resolution of hypernasality in 90% of patients. MULTIMEDIA
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Velopharyngeal Insufficiency excerpt Article Last Updated: Oct 14, 2006 | ||||||||||||||||||||||||||||||||||||||||