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Cleft palate repair

 

The presence of cleft palate has both aesthetic and functional implications for patients in their social interactions, particularly on their ability to communicate effectively and on their facial appearance with or without involvement of the lip.

 

Midfacial skeletal growth may be affected by the surgical repair of the palate. The treatment plan focuses on two areas: speech development and facial growth. Speech development is paramount in the appropriate management of cleft palate.

 

Many surgical techniques and modifications have been advocated to improve functional outcome and aesthetic results. The most controversial issues in the management of cleft palate are the timing of surgical intervention, speech development after various surgical procedures, and the effects of surgery on facial growth.

 

The major goals of surgical intervention are normal speech, minimizing growth disturbances, and establishing a competent velopharyngeal sphincter.

 

History of the Procedure

 

Rogers and Georgiade expertly reviewed the evolution of cleft palate surgery. The first record of a palatal operation dates to 500 AD and was prompted by inflammation of the uvula. In 1552, Houlier proposed suturing palatal clefts and 12 years later Ambroise Pare illustrated obturators for palatal perforations.

 

In 1764, Le Monnier, a French dentist, successfully repaired a cleft velum with a few sutures and hot cautery of the edges. von Graefe, 50 years later, produced inflammation of the velar margins before bringing them together in his palate suture and is credited with performing the first velar repair of a cleft in 1816. JC Warren performed the first velar closure in America in 1824.

 

In 1828, Dieffenbach enhanced the surgical treatment of cleft palate by introducing hard palatal mucosa elevation to allow the closure of hard palatal cleft. von Langenbeck (1859) proposed the creation of a bipedicle mucoperiosteal flap that can be mobilized medially to close the palatal cleft. The improved vascular supply of the mucoperiosteal flap significantly decreased the incidence of dehiscence. See the image below.

 

figure

The von Langenbeck repair. Two bipedicle mucoperiosteal flaps are created by incising along the oral side of the cleft edges and along the posterior alveolar ridge from the maxillary tuberosities to the anterior level of the cleft. The flaps are then mobilized medially with preservation of the greater palatine arteries and closed in layers. The hamulus may need to be fractured to ease the closure.

 

With the ability to successfully close the palate, concern about palatal function was raised. It was evident by this time that the short and immobile palate impaired the speech capability of patients with cleft palate.

 

Veau, Kilner, and Wardill described the unipedicled mucoperiosteal flap based posteriorly on the greater palatine artery that pushed the flap posteriorly to lengthen the palate. The scarring of the denuded bone areas anteriorly and laterally was suspected as the cause of facial growth retardation posteriorly.

 

In 1994, Schweckendiek advocated the use of a 2-stage cleft palate closure. The soft palate was closed early, with closure of the hard palate delayed until several years later. The rationale for the 2-stage procedure was to provide improved velopharyngeal function during the initial speech development and to accomplish the closure of the hard palate after the cleft narrows with facial growth. Anatomic muscle realignment has also been postulated as essential in improving postoperative velopharyngeal function.

 

A topic for debate has been over the treatment of the alveolar cleft that accompanies the cleft palate. The rationale for its closure includes stabilizing the maxillary arch, providing support for tooth eruption and postsurgical orthodontics, closing oronasal fistulae, and improving the aesthetics of the mid face and nose. The current trend is toward secondary bone grafting at the time of mixed dentitia, with early (primary) grafting potentially proving detrimental to midfacial growth.

 

Much discussion has centered over the role and timing of pre-surgical appliances. Both the hard palate and the alveolus can be molded with passive molds and active devices, with the shared ultimate goals of facilitating surgical repair and providing an improved long-term outcome in both facial form and palatal function.

 

These historic developments in the treatment of the cleft palate underlie the existing controversies still found today.

 

The incidence of cleft lip/palate by race is 2.1/1000 in Asians, 1/1000 in whites, and 0.41/1000 in blacks. Isolated cleft palate shows a relatively constant ratio of 0.45-0.5/1000 births.

 

The foremost type of clefting is a bifid uvula, occurring in 2% of the population. The second most frequent type is a left unilateral complete cleft of the palate and prepalatal structures. Midline clefts of the soft palate and parts of the hard palate are also common.

 

Complete clefts of the secondary palate are twice as common in females as in males while the reverse is true of velar clefts. About 7-13% of patients with isolated cleft lip and 11-14% of patients with cleft lip/palate have other anomalies at birth.

 

Pathophysiology

 

The pathologic sequelae of cleft palate include feeding and nutritional difficulties, recurrent ear infections, hearing loss, abnormal speech development, and facial growth distortion.

 

The communication between the oral and nasal chamber impairs the normal sucking and swallowing mechanism of the cleft infants. Food particles reflux into the nasal chamber.

 

The abnormal insertion of the tensor veli palati prevents satisfactory emptying of the middle ear. Recurrent ear infections have been implicated in the hearing loss of patients with cleft palate. The hearing loss may worsen the speech pathology in these patients. Evidence that repair of the cleft palate decreases the incidence of middle ear effusions is inconsistent. However, these problems are overshadowed by the magnitude of the speech and facial growth problems.

 

Speech abnormalities are intrinsic to the anatomic derangement of cleft palate. The facial growth distortion appears to be, to a great extent, secondary to surgical interventions. Along with an intact hard palate, an intact velopharyngeal mechanism is essential in production of high pressure consonants and the oral resonance of vowels.

 

The velopharyngeal mechanism must also remain open to some degree to accomplish nasal resonance of m, n, and ng. With connected spontaneous speech, oral and nasal speech contexts are rapidly coarticulated, resulting in the complex need for millisecond timing of velopharyngeal closure and opening, depending on the speech targets.

 

Presentation:

 

1- Feeding

 

Although a child with cleft palate may make sucking movements with the mouth, the cleft prevents the child from developing normal suction. However, in general, swallowing mechanisms are normal. Therefore, if milk or formula can be delivered to the back of the child’s throat, the infant feeds effectively.

 

Breastfeeding is usually not successful, unless milk production is abundant, but most infants can bottle feed with more specially designed bottles and nipples.

 

2- Airway

 

The infant with Pierre Robin anomaly or other conditions in which the cleft palate is observed in association with a micrognathia or retrognathic mandible may be particularly prone to upper airway obstruction.

 

3- Middle ear disease

 

The disturbance in anatomy associated with cleft palate affects the function of the eustachian tube orifices. Parents and physicians should be aware of the increased possibility of middle ear infection so that the child receives treatment promptly if symptoms arise.

 

4- Associated deformities

 

In as many as 29% of patients, the child with cleft palate may have other anomalies. These may be more commonly associated with isolated cleft palate than with cleft lip/palate. High among the associated anomalies are those affecting the circulatory and skeletal systems.

 

Indications

 

Children born with a cleft palate should undergo surgical repair unless otherwise contraindicated. The main goal is to perform a functional repair of the soft palate musculature through the repositioning of the abnormally-oriented and attached muscles.

 

This anatomic repair attempts to facilitate the development of normal speech. While separation of the oral and nasal cavities is advantageous to normalize feeding and decrease regurgitation and nasal irritation, it is not absolutely necessary for feeding.

 

Palate repair with repositioning of the palatal musculature may be advantageous to eustachian tube function and ultimately to hearing. Because the levator and the tensor veli palatini have their origins along the eustachian tube, repositioning improves function of these muscles, improves ventilation of the middle ear, and decreases serous otitis, which further decreases the incidence of hearing abnormality. Palate repair alone does not usually completely correct this dysfunction and additional therapy frequently includes placement of ear tubes as necessary.

 

Relevant Anatomy

 

The bony portion of the palate is a symmetric structure with division based on the embryonic origin into the primary and secondary palate.

 

The premaxilla, alveolus, and lip, which are anterior to the incisive foramen, are parts of the primary palate. Structures posterior to it, which include the paired maxilla, palatine bones, and pterygoid plates, are part of the secondary palate.

 

The severity of the clefting of the bony palate varies from simple notching of the hard palate to clefting of the alveolus. See the image below.

Anatomy of the palate.

 

The palatine bone is located posterior to the maxilla and pterygoid lamina. It is composed of horizontal and pyramid processes. The horizontal process contributes to the posterior aspect of the hard palate and becomes the floor of the choana. The pyramidal process extends vertically to contribute to the floor of the orbit.

 

Even though the bony defect is important in the surgical treatment of cleft palate, the pathology in the muscles and soft tissues has the greatest impact on the functional result. Six muscles have attachment to the palate: levator veli palatini, superior constrictor pharyngeus, uvulus, palatopharyngeus, palatoglossus, and tensor veli palatini.

 

The 3 muscles that appear to have the greatest contribution to the velopharyngeal function are the uvulae, levator veli palatini, and superior constrictor pharyngeus.

 

The uvulae muscle acts by increasing the bulk of the velum during muscular contraction. The levator veli palatini pulls the velum superiorly and posteriorly to appose the velum against the posterior pharyngeal wall.

 

The medial movement of the pharyngeal wall, attributed to superior constrictor pharyngeus, aids in the opposition of the velum against the posterior pharyngeal wall to form the competent sphincter. The palatopharyngeus displace the palate downwards and medially.

 

Workup:

 

Laboratory Studies

 

Routine laboratory studies are noncontributory in otherwise healthy infants with cleft palate. Some centers obtain a blood count as a routine study before performing surgery on a child with cleft palate.

 

Medical Therapy

 

The Pierre Robin sequence is classically associated with retrognathia, glossoptosis, respiratory distress, and a cleft palate. If untreated, death may result from obstruction by the tongue, which has fallen back in the airway. The most appropriate first step in management is to place the infant in the prone position to allow the tongue to fall forward and clear the trachea.

 

Orthodontic interventions

 

The available data suggest that to optimize speech development, some degree of facial growth distortion may need to be accepted. One role of orthodontic intervention is to minimize the severity of the growth disturbance. Interventions vary according to the type of cleft.

 

Many types of orthodontic appliances have been used in the treatment of patients with cleft palate. In cleft lip/palate, orthodontic appliances can be used to realign the premaxilla into a normal position prior to lip closure.

 

Orthodontic interventions in patients with cleft palate are frequently aimed at maxillary arch expansion, correction of malocclusion, and correction of an often developing class III skeletal growth pattern. The maxillary dental arch contracture may become significant, requiring the surgical repair of the hard palate.

 

Orthodontic interventions may be started early or delayed for several years. When orthodontic manipulation is initiated early, difficulties may occur. Maintaining orthodontic appliances in the infant population may present a challenge unless these appliances are fixed in position.

 

The beneficial influence of these orthopedic interventions has also been questioned, especially in isolated patients with cleft palate. The most beneficial period for orthodontic interventions in isolated cleft palate may be during the mixed dentition period.

 

At approximately age 6-8 years, the permanent incisors are erupting. During this period, children are beginning to have social interactions with their peers. The presence of grossly malaligned teeth and severe malocclusion can lead to social isolation.

The incisor relation can be corrected and maintained with relatively simple interventions. Patients who undergo palatal arch expansion therapy during this period can benefit from the rapid growth phase.

 

The orthodontic intervention can also proceed with more cooperation from the patient in this age group. Orthodontic management of arch deformities after the permanent dentition has erupted is more limited.

 

The established malocclusion and asymmetry between the maxillary arch and mandibular arch usually require orthognathic surgery.

 

Surgical Therapy

 

Timing of palatal closure

 

The timing of surgical repair of cleft palate remains controversial. The goals of palatal repair include normal speech, normal palatal and facial growth, and normal dental occlusion.

 

Physicians believe that early palate repair is associated with better speech results but early repair also tends to produce severe dentofacial deformities. Randall and McComb as well as Lehman and colleagues consistently reported that children whose palates were repaired at an earlier age appeared to have better speech and needed fewer secondary pharyngoplasties than those whose surgeries had been delayed beyond the first 12 months.

 

Noordhoff and associates found that children undergoing delayed palatoplasty for cleft palate had significantly poorer articulation skills before the hard palate closure than children of the same age who did not have clefts.

 

These benefits of early cleft palate repair from the standpoint of speech and hearing must be weighed against the increased technical difficulty of the procedure at a younger age and possible adverse effects on maxillary growth.

 

Numerous studies failed to demonstrate an observable difference in underdevelopment of the palatal arch among children undergoing operations at various ages.

 

The surgical intervention appears to interfere with midfacial growth without regard to the age of the patient at the time surgery is performed.

 

Bifid uvula occurs in 2% of the population. Although bifid uvula occurs in association with submucous cleft palate, most infants with bifid uvula do not have this problem. The recommended management of a bifid uvula is close observation to ensure that speech develops normally.

 

Sequence of operations

 

Multiple protocols for the management of CL/P have been suggested over the years by various authors. Today, the mainstream of cleft repair calls for closure of the lip at an early age (from 6 wk to 6 mo) followed by closure of the palate secondarily approximately 6 months later. This protocol has little impact on facial development.

 

When managing a residual alveolar defect and an associated oronasal fistula, the primary goal of surgery is to allow subsequent development of a normal alveolus.

 

Optimal eruption of teeth at the cleft site and development of normal periodontal structures of the teeth adjacent to the cleft occur when bone grafting and final fistula closure are performed prior to eruption of the permanent canine at the cleft site.

 

Choice of operation

 

The list of surgical techniques used in palatal cleft closure is extensive. The repairs differ depending upon whether the cleft is an isolated cleft palate or part of a unilateral or bilateral cleft lip and palate.

 

The 3 main categories include

(1) simple palatal closure,

(2) palatal closure with palatal lengthening, and (3) either of the first two techniques with direct palatal muscle re-approximation.

 

Von Langenbeck procedure

 

The simple palatal closure was introduced by von Langenbeck and is the oldest cleft palate operation in wide use today. The bipedicle mucoperiosteal flaps were created by incising along the oral side of the cleft edges and along the posterior alveolar ridge from the maxillary tuberosities to the anterior level of the cleft.

 

The flaps were then mobilized medially with preservation of the greater palatine arteries and closed in layers. The hamulus may need to be fractured to ease the closure. The von Langenbeck repair continues to be popular because of the simplicity of the operation.

 

This technique can successfully close moderate-size defects. Modern critics of the von Langenbeck technique cite the unnecessary anterior fistulas it promotes, the insufficiently long palate it produces, and the inferior speech result associated with it.

 

Trier and Dreyer combined primary Von Langenbeck palatoplasty with levator sling reconstruction (intravelar veloplasty). Better speech and superior velopharyngeal function were observed following intravelar veloplasty with muscle reconstruction and careful reconstruction of the levator sling at the time of palate repair is recommended.

 

Palatal lengthening – V-Y pushback

 

Veau’s protocol for closure of cleft palate stressed the need for (1) closure of the nasal layer separately, (2) fracture of the hamular process, (3) staged palatal repair following primary lip and vomer flap closure, and (4) creation of palatal flaps based on a vascular pedicle.

 

Kilner and Wardill devised a technique of palatal repair in 1937 that was more radical than Veau’s and that ultimately became the V-Y pushback. It includes lateral relaxing incisions, bilateral flaps based on greater palatine vessels, closure of the nasal mucosa in a separate layer, fracture of the hamulus, separate muscle closure, and V-Y palatal lengthening.

 

The 4-flap technique is similar to the Wardill-Kilner 2-flap technique, except the oblique incisions are more posterior to create 4 unipedicle flaps. The flaps are again mobilized medially and closed.

 

These pushback techniques achieve greater immediate palatal length but at the cost of creating a larger area of denuded palatal bone anterolaterally. The gain in the length of the palate has not been demonstrated to be permanent or translated to improve velopharyngeal function. This approach has been associated with a higher incidence of fistula formation.

 

Intravelar veloplasty

 

Several studies have emphasized the necessity of realignment of the muscle in the soft palate. The stratagem was designed to lengthen the palate as well as to restore the muscular sling of the levator veli palatini. Improved velopharyngeal function was sporadically reported. Marsh et al conducted a prospective study of the effectiveness of primary intravelar veloplasty and found no significant improvement in velopharyngeal function.

 

Double-opposing Z-plasties

 

In 1986, Furlow described a single-stage palatal closure technique consisting of double opposing Z-plasties from the oral and nasal surfaces. Use of the double Z-plasty minimized the need for lateral relaxing incisions to accomplish closure.

 

The palate was also lengthened as a consequence of the new position of the velar and pharyngeal tissues. Preliminary data revealed that speech development was excellent, with 86% exhibiting normal speech in Furlow’s study. See the image below.

Double-opposing Z-plasties. Furlow’s single-stage palatal closure technique consisting of double opposing Z-plasties from the oral and nasal surfaces. The double Z-plasty minimizes the need for lateral relaxing incisions to accomplish closure. The palate is lengthened as a consequence of the new position of the velar and pharyngeal tissues.

 

Others have confirmed the improvement in speech development. The closure of the hard palate in Furlow’s technique avoids the use of lateral relaxing incisions.

 

The mucoperiosteal flaps are mobilized from the bony hard palate and the palatal defect closed by tenting the flaps across and creating a moderate empty space between the flaps and the bony hard palatal vault.

 

Furlow’s technique appears to be quite successful in clefts of limited size. In moderate-size clefts, lateral relaxing incisions may still be required to obtain closure.

 

Two-flap palatoplasty

 

Bardach and Salyer independently modified the two-flap palatoplasty to combine elements of other operations with some innovative details. The main goals are complete closure of the entire cleft without tension at an early age (< 2 mo), with minimal exposure of raw bony surfaces and the creation of a functioning soft palate.

 

The authors believe that a muscle sling within the soft palate, not velar lengthening, is essential to adequate speech. Morris and colleagues note that 80% of patients treated with this method developed velopharyngeal function within normal limits, although 51% required speech therapy before normal speech production could be expected. See the images below.

Two flap palatoplasty. After lateral relaxing incisions are performed, bilateral flaps are elevated based on greater palatine vessels.

 

Two-flap palatoplasty (continued). Closure of the nasal mucosa is performed. The hamulus may be fractured, the muscle is repaired, and the oral mucosa is closed as a separate layer.

 

In a further modification of the two-flap palatoplasty, the mucoperiosteal flaps are rotated medially. In a study by Black and Gampper, patients who underwent surgery with this technique demonstrated comparatively low rates of velopharyngeal insufficiency and oronasal fistula development (5.7% and 8.6%, respectively).]

 

Velar closure – Delayed hard palate closure

 

Schweckendiek closed the soft palate early (at age 6-8 mo) but left the hard palate open, albeit occluded with a prosthetic plate, until aged 12-15 years.

 

In unilateral clefts the soft palate is closed first, followed by lip surgery 3 weeks later. In bilateral clefts one side of the lip is closed first in conjunction with primary veloplasty, with repair of the other side of the lip and the alveolar cleft 3 weeks later.

 

Schweckendiek reports normal jaw development subsequent to this protocol. Many European surgeons now use Perko’s approach of 2-stage palatal closure. Repair of the soft palate occurs at age 18 months and of the hard palate at 5-8 years.

 

Perko found that the remaining cleft in the hard palate does not disturb speech development to a relevant degree.

 

Several long-term assessments of patients who undergo the Schweckendiek approach or the Zurich approach (as described by Perko) disclosed an unusually high incidence of short palate and poor mobility of the soft palate, with a correspondingly high degree of velopharyngeal insufficiency (VPI). Conversely, facial growth was judged to be quite acceptable in most patients

 

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