1 INTRODUCTION

Velopharyngeal insufficiency (VPI) is a significant speech disorder. This is usually identified and addressed in childhood, but may be seen as a consequence of central nervous system disease or injury, peripheral nerve injury or palate resection with cancer ablation in the adult. VPIcan be a result of inappropriate articulation and hence, in these cases, remediable by aggressive speech therapy. All too often the treatment will need to be surgical. In this chapter, the surgical treatment will be addressed. Prosthetic management can be quite useful as well and will be addressed in the patient selection section, but will not be fully described here.

2 PATIENT SELECTION

Most children with VPI can be successfully treated by speech therapy. It is therefore imperative that the surgeon work closely with the speech pathologist in reduction of hypernasality, with appropriate phoneme production. In the case of VPI following CNS injury, the speech pathologist may be needed to address both swallowing as well as speech. Because recovery of function may take months, surgical intervention in these cases should proceed only after there seems to be a cessation of improvement in function.

The trained ear may hear the hypernasality, nasal emission and nasal turbulence in structured samples or spontaneous speech. The use of a non-heated mirror beneath the nose may give a reasonable assessment of the leakage of air through the nose during speech tasks. As /m,n,ng/ are normally nasalized sounds, the speech sample should focus on the other consonant non-nasal phonemes including/p,b,t,d,s,sh,z/. If the phoneme is not appropriately articulated it may be hypernasal. If possible the sample should obtain isolated phonemes, single words, phrases, sentences and spontaneous speech. Focus should be on the phonemes that are accurately articulated. The assessment of appropriate articulation is best done by the speech pathologist. This emphasizes the need for team care of the person with VPI. Surgical intervention should not be the order when speech therapy alone could suffice.

Another objective measure of hypernasality is naso-metry, also called nasalence testing. The procedure compares the energy coming from the nose versus the mouth in a structured speech environment. With a sample loaded with non-nasal phonemes, hypernasality will be documented as a higher number and is compared to an established normal. It is rated as the number of standard deviations from the mean. If the sample is well articulated and there is good co-operation, this can be a help in deciding the need for surgical intervention.

Occasionally it is felt that the patient needs aggressive intervention, but is not a surgical candidate. These situations include severe airway obstruction, progressive disease, and prior radiation therapy to the airway or medical problems that would reduce the advisability of surgery. In these cases prosthetic management should be considered. An adequately long palate can be lifted to allow velopharyngeal competence or an obturator placed behind the palate can be used. The obturator is especially useful if there is a soft tissue defect from a cancer ablation or if the palate is congenitally short and the palatal lift cannot allow complete closure.

The appliance is clasped to the teeth and may be used during the day, but is removed for cleaning and sleep. This is of special help for both adults and children with a risk of obstructive sleep apnea. Children with other craniofacial syndromes may be at special risk for airway obstruction and prosthetic management may be a good option for them. Endoscopy can help with the determination of the need for prosthesis, as well as its fitting.

If the decision is made that surgery is necessary, endoscopic evaluation of the velopharynx during speech is needed to decide the type and extent of surgery needed.

Though some use only a single surgical procedure for all, there is wisdom in deciding the surgery based on the shape and the size of the ‘gap’ that needs obturation. A coronal or circular closure pattern may be more successful with sphincter pharyngoplasty than the sagittal closure pattern, as the area needing obturation may be more lateral. A pharyngeal flap that obturates the central velopharynx may be more helpful in these situations. If there is a small central gap, one should consider an augmentation.

If the levator veli palatini muscles are longitudinal in orientation rather than transverse, consideration must be given to either an intravelar veloplasty or a Furlow double opposing Z-plasty. In both of these operations the levator is reoriented to improve palatal motion, thereby correcting the VPI. The Furlow will be described in detail here.

Regardless of which surgical intervention is chosen, there is a potential effect on the airway. The Furlow lengthens and thickens the palate. All of the others to a greater degree reduce the cross-sectional airway areaat the velopharynx. This alteration unfortunately mayprecipitate immediate post-surgical airway obstructionand OSA or sleep-disordered breathing, also. In general it seems the procedures from least to most obstructive are: Furlow, augmentation, sphincter and pharyngeal flap. Of course, each of the latter three may be altered tosome extent to increase or decrease nasopharyngeal obturation and hence airway obstruction. This is based onthe degree of motion of the velopharynx during speech. Care must be taken in the decision for surgical interven-tion to offer informed consent with regard to the airway issues.

As one considers surgery for VPI, it is important to plan the procedure based on the endoscopic findings. As was discussed above, one should consider the Furlow for any submucous cleft palate, as one could hope the reorientation of the levator sling would allow improved closure. If there is substantial lateral wall motion, the pharyngeal flap is ideal as it allows obturation without as much airway risk as a wide flap. Sphincter pharyngoplasty works well for most situations, as most people will have a circular or coronal closure pattern and this obturates the lateral and posterior velopharynx.

The association of 22q11 microdeletions (velocardiofacial syndrome) with especially non-cleft VPI makes it imperative to consider cardiac disease in the population of children with VPI. Careful examination and clearance by pediatrics or cardiology are important. Additionally many children with this syndrome will have medialization of the great vessels. This is often seen endoscopically as a pulsatile area in the hypo- or velopharynx. Though usually one may be able to successfully and safely complete the speech surgery even in this setting, it is critical to know this is present and avoid injury to the vertebral or carotid artery. Not only should this be considered at endoscopy, but as the pharynx is inspected as the mouth gag is placed, one should always re-evaluate for pulsation.

3 COMMON CONSIDERATIONS FOR THESEPROCEDURES

The surgery is performed under general anesthesia. Usually the use of an oral RAE tube will allow less interference with the field. The Dingmann mouth gag is usually used. It has the advantage of self-retaining lateral retractors and springs to allow suture retention. Other mouth gags used in tonsil surgery can be employed as well. Craig Senders suggested that releasing the pressure on the tongue during the surgery allowed improved blood flow and likely decreased pain.¹

Local infiltration of the flap areas is necessary for hemostasis and will decrease local pain to make the anesthesia smoother. Lidocaine with epinephrine is good, but has a relatively shorter duration of pain control.

A throat pack is suggested, especially if the endotracheal tube is non-cuffed. This will hopefully prevent both aspiration of blood around the endotracheal tube and also swallowing of blood that could increase the chance of postoperative nausea.

At the end of surgery, a tongue suture can be placed. This is tied loosely and the tail remains long. It is taped to the side of the mouth. In the event of postoperative airway obstruction, pulling the tongue anteriorly with the suture will improve the airway. This is usually removed the following morning if the airway is secure.

4 FURLOW DOUBLE OPPOSING Z-PLASTY

The Furlow double opposing Z-plasty is quickly becoming a standard way of repairing a cleft palate. The advantage is the reorientation of the levator. If the levators are longitudinal one must consider the Furlow, or completely dissecting the levators to perform an intravelar veloplasty. In this chapter the focus will be on the Furlow.

A Z-plasty lengthens a scar. In VPI the problem often includes a short palate. The double Z-plasty lengthens the palate. The initial ‘Z’ can be made in either direction but the right-handed surgeon seems to do better as pictured (Fig. 59.1A). The posteriorly based flaps are always the myomucosal flaps. The anteriorly based flaps are mucosa only. Kathy Sie suggests rounding the tips of the flaps to improve the vascular supply.² The incision is carried through the oral cavity mucosa. As the incision is madein the left hemipalate, care must be taken to maintain a small amount of mucosa behind the posterior edge of the hard palate so that suturing is easier. Careful dissection through the levator and tensor veli palatini tendon brings one to the nasal mucosal layer. The plane is usually well defined. Meticulous blunt and sharp dissection separates the undersurface of the muscle bundle from the nasal mucosa.

Fig. 59.1 Furlow. A, The dashed line indicates the location of the incisions for the initial Z-plasty. The dotted line describes the posterior border of the hard palate. Flap (A) is the oral cavity myomucosal flap and flap (B) is the mucosal flap. B, The posteriorly based myomucosal flap (A) has been elevated as has the anteriorly based mucosal flap (B). The dashed lines show the location for the incisions to create the nasal layer myomucosal flap (D) and the nasal mucosal flap (C). C, The flaps (C) and (D) have been rotated and sutured into position. The uvula is often divided at this point to grant more mobility to the flap (D). The flaps (A) and (B) are retracted out of the field to improve the access for suturing the nasal layer. D, The flaps (A) and (B) have been rotated to create the second Z-plasty. They have been sutured into position. The uvula has been closed. The dashed line shows the location of the closure of the nasal Z-plasty.

The anteriorly based mucosal flap is raised off the palatal muscles. This mucosa is markedly thicker than the nasal mucosa, but is still prone to injury if the dissection is not careful. The midline incision can be made through the palate at the initial step of the operation, or once both oral flaps are raised (Fig. 59.1B).

Approaching the nasal layer, the posterior left hemipalate incision is made to create the anteriorly based mucosal flap. The right hemipalate incision is made anterior near the hard palate edge to allow the myomucosal flap to be posteriorly based. Again it is important to leave a cuff of muscle and mucosa to facilitate the closure.

The nasal layer is closed by rotation of the left nasal mucosal flap across the midline, suturing it to the area of the right posterior hard palate. The nasal layer myomucosal flap is rotated to the left to be sutured to the defect. This places the midline incision at the posterior left hemipalate and the anterior incision along the nasal mucosal flap (Fig. 59.1C).

The oral mucosal flap is now rotated to the left and the myomucosal flap rotated to the right and closed. One can see the muscle bundles are now in a horizontal orientation and posterior in the palate. The mucosal layers are more anterior against the hard palate. The uvula is reapproximated (Fig. 59.1D).

5 PHARYNGEAL FLAP

The pharyngeal flap has been the ‘workhorse’ for years. Though many have abandoned this procedure in favor of sphincter pharyngoplasty, it is still useful and in experienced hands affords excellent results.

The idea is to bring a superiorly based midline flap from the pharynx and insert this into the palate. The following will describe one approach that allows mucosal covering of the flap to decrease flap contracture.

The surgery is done with a midline split of the soft palate (Fig. 59.2A). The posteriorly based nasal mucosal flap is elevated from the palate with careful blunt and sharp dissection. The nasal mucosa is divided just at the hard–soft palate border. The midline pharyngeal flap is developed from the center of the pharynx. Its width would be determined by the degree of obturation needed, as based on the preoperative endoscopy. This is elevated to the level of the hard palate.

Fig. 59.2 Pharyngeal flap. A, The incisions for the palatal split and the posterior pharyngeal flap have been outlined with a dashed line. The dotted line defines the posterior border of the hard palate. The initial incision in the palate is carried through the oral cavity and nasal mucosa. The hemipalates can be rotated laterally to improve the exposure to the posterior pharyngeal wall. The incision in the posterior pharyngeal wall is carried to the fascia. Because the flap will retract, it should be made slightly longer than you might expect. This is a myomucosal flap. B, The nasal mucosal layer (nm) has been delicately elevated from the muscle bundle and rotated laterally. The tip on the left is labeled (A¹) and that on the right labeled (A²). The elevated pharyngeal flap (pf) is rotated superiorly and sutured to the posterior aspect of the hard palate. The uvula (u) is, of course, divided. C, The nasal mucosal layer (nm) is sutured overthe raw surface of the pharyngeal flap (pf). The remainder of the palate isclosed in three layers: oral mucosa and uvula, muscular layer and finally the nasal layer.

In order to reduce the possibility of lateral port scarring that will increase the risk of postoperative airway obstruction, either an endotracheal tube or other catheter is placed through each nare and brought into the nasopharynx. The catheter size is determined by the desired port size.

The pharyngeal flap is sutured to the posterior aspect of the hard palate (Fig. 59.2B). The nasal mucosal flaps are then sutured to the pharyngeal flap to cover the raw surface area. The soft palate is then closed in layers, reapproximating the muscle, the oral cavity mucosa and the uvula (Fig. 59.2C).

The defect in the posterior wall may be loosely approximated.

6 SPHINCTER PHARYNGOPLASTY

This operation has become a standard surgery for the treatment of VPI. The fundamental design is to create a posterior and lateral ridge. The palate will contact this during speech. Because the coronal and circular closure patterns are the most common, this has been exceptionally useful. Originally the hope was that this would create a functional sphincter because of the myomucosal flaps. This rarely happens.

Superiorly based myomucosal lateral pharyngeal wall flaps are elevated (Fig. 59.3A). The flap can include the posterior tonsillar pillar, or only the lateral pharyngeal wall. If the posterior pillar is used the flap tends to be more obstructive but is very useful in a large gap. The flap design is based on the amount of obturation needed. If little obturation is needed, the flap can be longer and narrower. If the sphincter needs to be tight, the shorter, wider flap creates a much smaller port.

Fig. 59.3 Sphincter pharyngoplasty. A, A uvula retractor is used to retract the palate superiorly. The dashed lines demonstrate the location of the incisions. In this drawing the posterior pillar is included in the flap. The horizontal portion of the incision is made as high in the nasopharynx as possible or at a level determined by the anatomy seen on endoscopy. The left superiorly based myomucosal flap is labeled (α) and the right labeled (β). The distal end of the flap (A) will be rotated to (A¹) and (B) will be rotated to (B¹). In order to have the raw surfaces juxtaposed the (β) flap will be rotated on its axis 180° degrees. B, The flaps are sutured into position in the nasopharynx. The lateral wall defects are loosely approximated. C, This sagittal view demonstrates the closure of the (α) and (β) flaps.

A horizontal incision is made at the point of insertion (Fig. 59.3A). This can be defined by the point of maximal palatal elevation as seen in a lateral x-ray taken during speech, landmarks seen at the time of endoscopy or, as in many cases, placed as high as possible in the nasopharynx. Often this can be problematic if there is adenoid tissue in the way. Suturing in the adenoids is difficult and increases the risk of bleeding and the flap not holding. De Serres presented a technique to help with this problem.³ A microdebrider is used to remove the adenoids from the area of the horizontal incision. Hemostasis is assured and the flaps can be sutured into this space.

There are many ways to suture the flaps. The most practical way is to bring the left flap into the nasopharynx, suturing the posterior cut edge to the superior portion of the horizontal incision. The right myomucosal flap must be rotated at its base 180° on axis and then into the nasopharynx so the anterior cut edge is sutured to the inferior aspect of the horizontal incision (Fig. 59.3B). This opposes the raw surfaces (Fig. 59.3C). The degree of overlap and the length and width of the flap determine size of the central port. Exposure of the nasopharynx can be difficult. Retraction of the palate can be done with a uvula retractor as seen in the illustrations or bilateral transnasal red rubber catheters. Adequate visualization for accurate suture placement is a must.

The free edges of the flaps are sutured together (Fig. 59.3C). The defect created as the flaps were raised can be loosely approximated as well.

7 POSTERIOR WALL AUGMENTATION

On endoscopy one may see a small gap. If the gap appears to be 7 mm or less one should consider a posterior wall augmentation. This pharyngoplasty will attempt to address just the small area of concern. For decades there have been many augmentation procedures described. A rolled superiorly based pharyngeal flap has achieved some degree of success, but there is concern that scar could reduce the durability. Injections of both man-made and body substances have been tried, but none have had long-term success.

The following is a technique that is easily performed and has been very successful. This technique uses acellular dermis (Alloderm®).

Two vertical incisions are made in the nasopharynx. This area should correspond to the identified area of leak on endoscopy. A pocket is elevated beneath the fascia. A moderate thickness Alloderm sheet is rolled and sutured with absorbable sutures to maintain the shape. One of these sutures is left long, to assist with placement.

A right-angle clamp is placed through the pocket and the long suture is grasped. The Alloderm roll is pulled into the pocket (Fig. 59.4&). Firmly holding the graft in position, multiple absorbable sutures are placed through the graft to stabilize it in the nasopharynx during the healing process. The long suture is cut and the vertical incisions closed.

Fig. 59.4 Posterior wall augmentation. A, The Alloderm® was rolled and sutured to retain its shape. At one end the suture is left long. After the bilateral vertical incisions are made, a tunnel is made beneath the fascia. Inserting a long right-angle clamp, the long suture is grasped and the rolled Alloderm® is pulled into the tunnel. It will be sutured into position and the vertical incisions closed. B, This sagittal view shows the orientation of the rolled Alloderm®.

This has less risk of airway obstruction. It can be used to augment a scarred pharyngoplasty. If the augmentation fails it does not preclude the use of any other pharyngoplasty. If the graft becomes exposed it may become infected and need excision. Postoperative antibiotic coverage is a must.

8 POSTOPERATIVE MANAGEMENT ANDCOMPLICATIONS

The use of anti-emetics during and after the operation will hopefully improve the immediate postoperative course. Antibiotics during and after the procedure may be helpful in preventing infection and improving healing.

Postoperative pain control is important. IV narcotics should be transitioned to oral as soon as possible. Unfortunately as there is some risk of airway obstruction with these procedures, one must always guard against respiratory depression with narcotics; close monitoring after surgery is important. This is especially important if there is micrognathia. The tongue suture will allow the tongue to be pulled forward to relieve the obstruction. This is important to consider in any child, but especially in those with risk factors for postoperative upper airway obstruction.

Usually hospitalization is necessary after surgery, until the child has adequate oral intake and the airway is assured.

Complications of the surgery include bleeding, airway obstruction, and failure to achieve normal resonance. In general meticulous dissection decreases the risk of bleeding. Intraoperative hemostasis should be achieved with bipolar or low wattage monopolar cautery. This will hopefully decrease unwanted scar formation.

Airway obstruction after these surgeries can be severe or mild. Obstructive sleep apnea is a commonly described complication of pharyngeal flap, but there are reported cases of this as well in sphincter pharyngoplasty. If appropriate, the use of a Furlow or posterior wall augmentation may reduce the risk of postoperative airway obstruction. Even in these cases, there can be obstruction in the child with other risk factors such as micrognathia or other craniofacial anomalies.

Revision of the sphincter and pharyngeal flap is possible to reduce the airway obstruction. This needs to be balanced against the speech concerns, and a repeat endoscopy should be carried out to allow an evaluation of where revision can safely be accomplished without worsening the speech. If there has been significant improvement of speech, continuous positive airway pressure (CPAP) and bi-level positive airway pressure (Bi-PAP) can be considered in the postoperative period. Often over time the need for this pressure-assisted breathing is reduced, whether through the growth of the child or physiologic changes in the velopharynx. There have been multiple reports of taking down a pharyngeal flap without deterioration of speech. This should be considered in the older child.

The endoscopy could also reveal adenoid enlargement or encroachment of the tonsils into the airway. Tonsillectomy should be considered even if the tonsils are small. Adenoidectomy is more difficult, but can be done with a microdebrider through the velopharyngeal port. If the port is too small, a transnasal partial adenoidectomy can be done with a microdebrider. Bearing this in mind, one should consider tonsillectomy and adenoidectomy prior to pharyngoplasty if they are large and endoscopically seem to be a potential for airway obstruction. The speech surgery should be delayed 2–3 months to allow healing of the nasopharynx and oropharynx.

Nasal obstruction can present as mouth breathing, snorting and inability to blow the nose. Occasionally the chief complaint will be hyponasality. Some children and families will be very annoyed with these symptoms. If the endoscopy suggests that a revision would not compromise speech, the flaps can be reduced surgically. Care must be taken to design the surgery based on the endoscopic findings and to make sure mucosal surfaces are closed. Exposed raw surfaces may increase scar formation and make the airway obstruction worse. Often if the obstruction follows a sphincter pharyngoplasty and there is a strong coronal closure pattern, the sphincter can be released laterally. The posterior obturation remains and the airway can often be increased three-fold.

9 SUCCESS AND POTENTIAL FAILURE OF THEPROCEDURE

In properly selected patients with good preoperative planning, the improvement in velopharyngeal function should exceed 90%. Syndromic patents will be more difficult to treat, especially those with Nager’s and velocardiofacial syndrome. Postoperative evaluation by speech pathology and nasalence testing can be helpful in determining the success of these surgeries.

If the surgery failed to eliminate the hypernasality, one must consider possible reasons. Hypernasality may be related to continued articulation issues. The family needs to know this preoperatively. There is usually a need for ongoing speech therapy to perfect the articulation. This is especially the case in maladaptive or compensatory articulation.

Postoperative endoscopy may show air leakage during appropriately articulated phonemes. If the Furlow has failed, one can use any of the other techniques to eliminate the hypernasal resonance. The use of the posterior wall augmentation does not ‘burn bridges’ for using either the sphincter or pharyngeal flap. Revision of the sphincter can be more easily undertaken than in the pharyngeal flap. If there is residual VPI, endoscopy will define the area of concern. The resection of a ‘V’ from the flap followed by a two-layer closure, tightens the port. Raising an additional superiorly based myomucosal flap from the lateral pharyngeal wall and inserting that into the existing sphincter can bulk the area to further obturate the port. After a pharyngeal flap, endoscopy can define which of the ports is the problem and to what extent. The ports can be further obturated with a V–Y advancement flap on the lateral or posterior wall. Additional midline tissue can be added to the lateral aspect of the flap as well.

10 CONCLUSION

The treatment of VPI should be based on an understanding of the closure pattern during speech. A major potential risk of the surgery is airway obstruction, often demonstrated as obstructive sleep apnea. Of the procedures discussed, those with the least risk for airway obstruction are the Furlow and posterior wall augmentation. If there is postoperative sleep apnea the pharyngeal flap and sphincter can be revised to open the port and improve breathing, or CPAP or BiPAP can be used.