Two-Stage Palate Repair

51

Two-Stage Palate Repair

Robert M. Menard

KEY POINTS

Growth of the maxilla occurs through a combination of processes: sutural growth through the midpalatal suture (MPS), transverse palatine suture (TPS), and maxillary-vomerine suture (MVS), as well as by periosteal bone apposition.

Infants with unrepaired cleft palates lack the ability to separate the oral and nasal cavities, which leads to a predominance of posteriorly articulated consonant sounds.

The controversies surrounding the potential benefits versus drawbacks of two-stage palate repair stem entirely from the lack of long-term, prospective studies assessing the technique.

The recommended age for soft palate closure has varied from 3 to 24 months, and for delayed hard palate closure it varies from 6 months to more than 16 years.

Long-term studies have shown the benefits of a two-stage cleft palate repair technique both with regards to maxillary growth outcomes and for speech development and velopharyngeal adequacy.

As practitioners who treat infants, children, and adults with cleft lip and palate, we can agree that our overall goal is to achieve close to normal growth of the facial soft tissues and skeleton, while allowing for the development of as normal speech as possible. How to achieve this goal, however, is the greatest controversy in cleft lip and palate care. Perhaps most greatly contested is the debate between single-stage versus two-stage cleft palate repair. It has been nearly 100 years since Sir Harold Gillies1 first suggested the two-stage repair concept; since then, scores of reports either promoting or disparaging the technique have been published. The purpose of this chapter is to review the advantages and disadvantages that have been presented in the literature and to present the latest protocols for surgical technique and timing that have been validated by prospective, longitudinal studies. Innovations that might be added to these techniques to optimize results are also explored.

MAXILLARY GROWTH AND SPEECH DEVELOPMENT

Maxillary Growth

Growth of the maxilla occurs through a combination of processes. Sutural growth occurs in the midpalatal suture (MPS), transverse palatine suture (TPS), and maxillary-vomerine suture (MVS) (Fig. 51-1); the midpalatal suture allows for lateral growth, whereas the transverse palatine suture allows for anteroposterior growth. The maxillary–vomerine suture contributes to anteroinferior growth of the entire maxilla.26

Growth also occurs with periosteal bone apposition (see Fig. 51-1). This apposition deposits bone in large part along the posterior palate and maxillary tuberosities, allowing for growth in the sagittal plane and making room for the molar teeth. Vertical growth results from bone apposition along the alveolar process and in connection with tooth eruption. In addition to the contribution of the maxillary–vomerine suture, growth of the maxilla inferiorly also occurs from bone deposition on the oral side of the palate, with concurrent bone resorption on the nasal side.

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Fig. 51-1 Maxillary bone growth. A, Axial view of maxilla. The midpalatal suture (MPS) allows for lateral growth of the maxilla, whereas the transverse palatal suture (TPS) allows for anteroposterior growth. Hatched lines indicate sutural growth, and punctate dots denote appositional growth, which is especially prominent along the posterior maxilla and alveolar process. B, Coronal view of the maxilla. Arrows indicate the directions of sutural growth, with notable appositional growth along the alveolar process. C, Sagittal view of the maxilla. Anteroinferior growth is seen along the maxillary–vomerine suture (MVS), with significant appositional growth along the posterior maxilla and alveolar process.

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Fig. 51-2 The three mucosal zones of the palate. The palatal fibromucosa (1) is thin and contributes to bone deposition on the oral palatal surface. The maxillary fibromucosa (2) is thick and contributes to the increasing depth and width of the palatal vault. The gingival fibromucosa (3) lies between the maxillary fibromucosa and the teeth and covers the alveolar ridge and teeth.

The palatal mucosa overlying the periosteum has also been implicated in the transverse development of the maxilla7 (Fig. 51-2). Three distinct zones have been recognized. The palatal fibromucosa is located in the midline, is thin, and contributes to the previously mentioned bone deposition on the oral palatal surface. The maxillary fibromucosa is thick, contains the neurovascular bundle, and contributes to increasing the depth and width of the palatal vault. The gingival fibromucosa lies between the maxillary fibromucosa and the teeth and covers the alveolar ridge and teeth. Scar tissue formation in any of these three regions, particularly the maxillary fibromucosa, will lead to growth restriction of the maxilla.

Speech Development

Speech development begins with the production of vowel sounds, starting at around 2 months of age. This is followed by the production of consonants, beginning with the back consonants, such as “h” and “g” around 2 to 3 months of age, and followed by the front consonants, such as “m,” “n,” and “p,” around 6 months of age. This marks the start of reduplicated, or canonical, babbling, with predominantly anteriorly produced consonants (such as “bababa”).8 Production of these anteriorly produced consonants is predicated on the infant’s ability to achieve velopharyngeal closure. Infants with unrepaired cleft palates lack the ability to separate the oral and nasal cavities, leading to a predominance of posteriorly articulated consonant sounds. In unoperated complete cleft palates, these posteriorly articulated consonants are most often glottally placed. Posterior oral consonant production has been shown to occur in infants with early soft palate closure (SPC)9 (Fig. 51-3). Opinions vary as to whether this predominance of posteriorly articulated consonant sounds during babbling in infants with cleft palates carries over into speech misarticulations. During the transition from babbling to normal early speech, however, a competent velopharyngeal mechanism is needed for the production of the intraoral pressure required to produce the anterior plosives. With incompetence of the velopharyngeal mechanism, the risk of compensatory pharyngeal or glottal articulation of the plosives and fricatives remains high. Infants and children with velopharyngeal competence after SPC but with residual clefts of the hard palate or alveolus have been shown to either retract their plosives to a position behind the opening (retracted oral articulation, see Fig. 51-3, C) or to maintain them anterior to the palatal defect, but with adaptations such as weakness or nasal air escape.10

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Fig. 51-3 Location of articulation of the plosive consonants. A, Normal articulation, with placement of different sounds indicated with circles. B, Compensatory glottal articulation secondary to velopharyngeal insufficiency, with sounds produced near the glottis. C, Retracted oral articulation of “t” and “d,” and occasionally “p” and “b,” secondary to a residual cleft or fistula of the hard palate.

CONTROVERSIES REGARDING TWO-STAGE PALATE REPAIR

The controversies surrounding the potential benefits and drawbacks of two-stage palate repair stem entirely from the fact that few long-term, prospective studies assessing the technique have been performed. Multiple retrospective publications have varied in the techniques used for hard palate closure and SPC, the use or lack of intraoral appliances, the timing of these procedures, the selection and nonrandomization of patients, the differences in timing and analysis of cephalometric studies toward following facial growth, the metrics and systems used to analyze speech outcomes, and the statistical methods used to analyze results. The results of these publications are compilations of nonlinear data collected in a nonstandardized fashion and fall under the definition of level III evidence, which leaves considerable variability in the reliability of the conclusions drawn.11 The following subsections examine these variations in greater detail.

Timing of Repair

The literature varies considerably regarding the timing of SPC and delayed hard palate closure (DHPC). The recommended age for SPC has varied from 3 to 24 months, and for DHPC it ranges from 6 months to more than 16 years.1219 These age recommendations are largely reflections of the personal experience of the individual cleft surgeon, without any scientific evaluation of their relevance.20 The timing of early SPC can be influenced by anesthetic and airway risks as well as operative difficulties secondary to the size of the cleft and oral cavity. For DHPC, the timing has often been considered a trade-off between speech development and maxillary growth. When evaluating outcomes, however, the timing of the palatal procedures has seldom been examined in relation to the precise details of the surgical methods used. This concentration on the timing of procedures to describe the two-stage palate repair without regard to the surgical technique used has created significant confusion about the results of two-stage palate repair.20 Regardless of the timing of the procedures, some techniques for SPC and DHPC denude more bone and cause more scarring of the soft tissues across the palatal sutures, resulting in poorer maxillary growth outcomes. This variability between techniques, while lumping them all together under the heading of “two-stage palate repair,” is one of the major factors in the discord between opponents and proponents of two-stage palate repair.

Surgical Techniques

Soft Palate

Gillies and Fry1 were the first to describe separation of the velum from the posterior hard palate in their two-stage technique. Separation of the mucosa and muscles at the junction of the soft and hard palates was necessary to lengthen the soft palate at the time of SPR.21 Reorientation of the velar muscles toward the midline brought the velum closer to the pharyngeal wall, as described in multiple SPR techniques. The extent of dissection used to achieve this, however, has differed significantly among techniques (Fig. 51-4).

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Fig. 51-4 Six published techniques of soft palate repair in two-stage palate repair. A, The technique proposed by Schweckendiek and Doz.19 A three-layer closure (nasal mucosa, muscle, and oral mucosa) is performed, followed by placement of an elastic strap across the nasal surface with lateral oral incisions; lateral clips are used to adjust the tension of the elastic strap. B, The technique proposed by Perko.21 Supraperiosteal mucosa flaps are elevated off the posterior third of the hard palate, denuding no bone. The velar muscles are reoriented toward the midline and repaired, and the nasal mucosa layer is lengthened by Z-plasty, with a V-Y pushback closure of the oral layer. The repair is anchored anteriorly using a vomer flap. C, The technique reported by Tanino et al.14 The oral mucosa at the junction of the soft and hard palates is cut, and the cleft muscles are dissected from the posterior margin of the palatal bone. The nasal mucosa is then freed from the posterior hard palate, and the repair is closed in three layers, reconstructing the palatal muscle sling by suturing together the released muscle bundles. D, The technique proposed by Chait et al.22 Two short posteriorly based mucoperiosteal flaps are raised, and the levator muscles are freed from the posterior edge of the hard palate. An intravelar veloplasty is carried out, with a three-layered closure with a slight pushback. The repair extends onto the posterior hard palate. E, The technique reported by Lilja et al.23 A zigzag incision is made at the junction of the hard palate and soft palate, and posteriorly based oral mucosal flaps are elevated. A posteriorly based vomer flap that does not reach the vomero–premaxillary suture is raised. The velar muscles and nasal mucosa are divided from the posterior insertion on the hard palate and rotated to the midline. The vomer flap is incorporated into the nasal layer closure, followed by reconstruction of the velar muscle sling and pushback closure of the oral mucosal layer. F, The technique proposed by Malek et al.13 A lazy-S incision is made at the junction of the hard and soft palates, and the pterygoid hamulus is infractured. The muscular attachments along the posterior margin of the hard palate are divided, and a posteriorly based vomer flap is incorporated into the nasal layer closure, followed by reapproximation of the velar muscles in the midline and oral mucosal closure.

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Fig. 51-5 Soft palate repair in a two-stage repair using a modified Furlow technique as described by Nishio et al.30 An anteriorly based vomer flap is incorporated into the oral layer closure anteriorly, and small posterior elevations of vomerine mucosa are used to anchor the nasal layer closure.

The further the dissection proceeds anteriorly and medially, the smaller the residual hard palate cleft. Although this could be considered an advantage in relation to speech development before DHPC, it had the disadvantage of increased maxillary growth impairment, particularly when growth-sensitive areas such as the transverse palatine suture were left denuded.20 To decrease tension and minimize the amount of anterior dissection required, some techniques have described a posteriorly based vomer flap in the repair of the anterior nasal mucosa layer.13,21,22 The vomer flap anchors the anterior part of the repaired velum to the lower nasal septum and elevates the velum to the height of the palatal shelves, helping to further reduce the size of the residual hard palate cleft.20

Since 2001, several groups have reported on use of a modified Furlow technique for closure of the soft palate in the first stage of the two-stage repair2427 (Fig. 51-5). The Furlow soft palate repair has been described both with and without an anteriorly based vomer flap. When soft palate closure completed with the Furlow technique at 12 months and DHPC performed at 18 months was compared with one-stage pushback palatoplasty at 12 months, improved AP palatal length, posterior maxillary sagittal growth, anterior facial height, and transverse palatal width was found with the two-stage technique.25,28,29

Hard Palate

Multiple methods for closure of the residual hard palate cleft have also been described. These DHPC techniques have varied according to the surgeons preference, the patient’s age, and the size of the residual hard palate cleft. In patients with minor residual clefts, successful two-layer closure has been described without wide mucoperiosteal undermining or lateral relaxing incisions (Fig. 51-6). Perko21 described a small, sliding mucoperiosteal flap for oral layer closure, leaving a small denuded area of bone to close by secondary healing. Turn-over vomer flaps, rotating the raw surface to face orally, have also been described; grafting with either full-thickness skin grafts or tibial periosteum has been described with these flaps to decrease the incidence of postoperative fistula formation. In wider clefts, traditional techniques such as those described by von Langenbeck,31 Wardill,32 and Dorrance33 have been used. The greater amount of palatal scarring associated with these techniques has been shown to increase the risk for restriction in maxillary length growth at the transverse palatal suture. As the timing of DHPC protocols moved earlier secondary to speech concerns and toward combining the procedure with alveolar cleft bone grafting, the amount of scarring generated became even more important because the hard palate was closed before maxillary growth had completed.

May 11, 2019 | Posted by in Oral and Maxillofacial Surgery | Comments Off on Two-Stage Palate Repair
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