Chapter 30: Cleft Palate

The secondary palate forms the hard palate posterior to the incisive foramen and the soft palate. The primary palate forms the hard palate anterior to the incisive foramen as well as the lip, nostril sill, and alveolus. The primary palate is formed by the medial and lateral nasal prominences of the frontonasal process migrating and fusing with the maxillary prominence during weeks 4–7 of gestation. The secondary palate is formed by migration and fusion of the lateral palatal processes of the maxillary prominence between weeks 5 and 12 of gestation. Therefore, the hard palate is unusual as it develops from both the primary and secondary palates.1–4

The bony palate develops from the primary and secondary palates. The primary palate (anterior to the incisive foramen) is formed by the premaxillary portion of the maxilla. The secondary palate (posterior to the incisive foramen) is formed by the palatine processes of the maxilla and the palatine processes of the palatine bone. In week 8, the lateral palatal processes are vertical and progress to a horizontal position as the tongue moves caudally. The palatal processes rotate at different times, with the right moving before the left. This may explain the higher incidence of left-sided clefts. Fusion of the palatal processes takes longer in females (approximately 1 week), which may explain an increased incidence of cleft palate in females. Interruption of the migration or fusion steps may result in a cleft palate.1–4

With the exception of the tensor veli palatini muscle, all of the muscles of the soft palate are innervated by the pharyngeal plexus, with contributions from cranial nerves IX, X, and XI. The tensor veli palatini muscle originates from the first pharyngeal arch and functions to open the Eustachian tube. This is logical embryologically because the first arch forms the second and third parts of the trigeminal nerve (Fig. 30.1).1–4

4. Marazita ML, Mooney MP. Current concepts in the embryology and genetics of cleft lip and cleft palate. Clin Plast Surg 2004;31(2):125–140

5. Kosowski TR, Weathers WM, Wolfswinkel EM, Ridgway EB. Cleft palate. Semin Plast Surg 2012;26(4):164–169 Submucous clefts have a triad of a posterior hard palate notch (not anterior), a bifid uvula, and a zona pellucida. The zona pellucida is a thin central area created by a diastasis of the soft palate musculature. It has a typical translucent appearance. The triad is sometimes referred to as Calnan’s triad, as it was described by him in 1954.1,2 Surgery is reserved for patients with velopharyngeal incompetence and may go unnoticed unless this is evident. Lower Fig. 30.1 Anatomy of the palate. Incisive foramen Greater palatine artery and nerves Greater palatine foramen Lesser palatine foramen Pterygoid hamulus Buccinator muscle Palatopharyngeus muscle Palatoglossus muscle Palatine tonsil Superior pharyngeal constrictor muscle Pterygomandibular raphe Lesser palatine artery and nerves Tendon of tensor veli palatini muscle Transverse palatine folds (rugae) Palatine process of maxilla Palatine glands Horizontal plate of palatine bone Palatine aponeurosis from tensor veli palatini muscle Interdigitating fibers of levator veli palatini muscle Uvular muscle Retromolar glands lip pits in conjunction with cleft palate is typical for Van der Woude syndrome, which is an autosomal dominant condition representing one-fifth of all syndromic cleft palates. It is not a feature of submucous cleft palate.3

A bifid uvula is effectively a partial cleft of the uvula and is traditionally regarded as a marker for submucous cleft palate. Submucous clefts are associated with the triad of bifid uvula, notching of the hard palate, and muscular diastasis of the soft palate.1 Bifid uvula can however occur spontaneously in many healthy and otherwise normal individuals. In fact, it is estimated that a bifid uvula is present in around 2% of the population. The frequency of the other clefts is far less common.1–3

The overall incidence of cleft lip with or without cleft palate, and isolated cleft palate is around 1:750 live births. The incidence of cleft lip with or without palate (CL/P) is affected by race and is highest in Asians at 1:500, but is less common in whites (1:1000) and blacks (1:2000). In contrast, the incidence of cleft palate (CP) is unaffected by race (1:2000 live births for all races). There is a gender difference in cleft lip and cleft palate. The male to female ratio for CL/P is 2:1, while the reverse is true for CP at 1:2.1–5

The standard risk for developing cleft palate is around 0.5% or 1 in 2000. The risk of having a child with an isolated cleft palate is significantly increased by either the parent or sibling having a cleft palate deformity. If unaffected parents have a child with a cleft palate, the risk of having another increases to 2%. If one parent has a cleft palate with no affected children, the risk for the first child is 6%. However, if an affected parent has one child with a cleft palate, the risk for the next child increases to 15%. These risks are relevant to clinical practice as parents will often wish to discuss risks during consultation.1–4

The baseline risk for developing a cleft lip/palate (CL/P) deformity is dependent on race and varies between 0.05 and 0.2% (0.5:1000 to 2:1000). The risk of having a child with a CL/P is significantly increased by either a parent or sibling having a cleft deformity. If one parent has CL/P with no affected children, the risk is 4%. However, if an affected parent has one child with CL/P the risk increases to 17%. The risk for normal parents with two CL/P children increases to 9%. Risks of 30 and 50% do not relate to CL/P development.1–4

Cleft palate can be syndromic or nonsyndromic. Nonsyndromic clefts are characterized by one defect or multiple anomalies that are the result of a single initiating event or primary malformation. Syndromic clefts are characterized by more than one malformation involving more than one developmental field. Associated anomalies are most commonly seen with isolated cleft palates. This can be as high as 70% where Pierre Robin sequence is included. Anomalies are also higher in bilateral cleft patients. Syndromic clefts include syndromes such as Stickler, velocardiofacial, and Van der Woude.1–3

The clinical features of Pierre Robin sequence are micrognathia/retrognathia and glossoptosis often with cleft palate. These can lead to significant airway problems, especially in young babies that require acute admission. The risk of airway compromise usually improves with age but in the acute setting needs meticulous care. Treatment includes lateral or prone positioning, and careful observation. In some cases, a nasopharyngeal airway or continuous positive airway pressure (CPAP) is required for a short duration. Occasionally tracheostomy is required. Infants with Pierre Robin sequence do not always have a cleft palate, but when one is present it tends to be wide and U-shaped as opposed to the normal V-shaped cleft.1,2

There are a number of syndromes associated with cleft palate (CP). The most common is Stickler syndrome, which represents 25% of all syndromic cases. This is an autosomal dominant condition with a mutation in the gene for type II collagen. The clinical presentation may include Pierre Robin sequence (but this is not specific to the other factors listed), ocular malformations, hearing loss, and arthropathies, each due to the collagen abnormality.1,2 Velocardiofacial and Shprintzen’s syndrome are different terms used to describe the same condition and represent 15% of syndromic CP. This autosomal dominant condition is associated with a deletion on chromosome 22. It is also therefore known as 22q11 deletion. It involves cardiovascular abnormalities, abnormal facies, and developmental delay.3,4 Van der Woude syndrome represents around 20% of all syndromic cleft palate cases. This is also autosomal dominant and is associated with lower lip pits.5 Other syndromes associated with cleft palate include Apert syndrome and Crouzon syndrome.

Folic acid and vitamin deficiencies are strongly associated with increased risk of cleft development. It is therefore really important to use oral folic acid and multivitamin supplements during early pregnancy. Doing so is also associated with a lower incidence of cleft lip or cleft lip and palate births in pregnant women with a family history of cleft lip/palate. The data on maternal smoking are inconsistent regarding the increased risk of clefts, but it probably does increase risk. Neither maternal alcohol nor caffeine ingestion is associated with increased risk. The risk of developing an isolated oral cleft increases with increased age of the parents, particularly if both are over the age of 30 years. Paternal age has the most profound effect.1–3

A major challenge for infants with isolated cleft palate is early feeding as the presence of a cleft palate prevents them from achieving a negative pressure required for adequate suction. Most infants and their parents require assistance in feeding which necessitates squeezy bottle with large cross-section fissures or sometimes a palate obturator. Specialist nurse and dietician support are provided within the multidisciplinary team to new parents to support them. Regular assessment of weight gain should be undertaken to assess progress. Airway issues and recurrent chest infections are not generally a concern in isolated cleft palate. Sleeping difficulties may occur secondary to poor feeding and subsequent hunger but are not themselves a specific issue associated with cleft palate. Physical appearance is unaffected in isolated cleft palate unlike cleft lip patients. The social impact centers on speech issues later in life.1

The soft palate can be repaired using an intravelar veloplasty or a double-opposing Z-plasty, as described by Furlow. Both of these techniques should improve functional outcomes in terms of speech and feeding. The intravelar veloplasty involves reorientation of the levator veli palatini muscle and palatopharyngeus muscle complex transversely following their dissection from the abnormal insertion.1,2 Furlow’s technique uses double- opposing Z-plasties based on the cleft midline. The anteriorly based flaps contain only mucosa, while the posteriorly based flaps contain mucosa and levator muscle complex. Nasal mucosal flaps are transposed and closed, the levator sling is reoriented transversely, and the oral mucosal flaps are transposed and closed. Although the soft palate is lengthened, as per Z-plasty techniques in general, the transverse dimension is reduced, thereby making closure of wide clefts more difficult and increasing the risk of subsequent fistula formation. The hard palate can be repaired with the von Langenbeck technique, the Veau-Wardill-Kilner technique (V-Y pushback palatoplasty), or the Bardach technique (two-flap palatoplasty). Selection of technique is often based on personal preference. The von Langenbeck palatoplasty uses bilateral bipedicled mucoperiosteal flaps with parallel incisions made along the cleft margin and lingual side of the alveolus. Nasal and oral mucosal flaps are mobilized and approximated in the midline. Poor speech outcomes have been attributed to the creation of a short immobile palate. These outcomes can be improved when combined with an intravelar veloplasty.3 The V-Y pushback technique involves bilateral mucoperiosteal flaps based on the greater palatine arteries. It incorporates a V-Y closure anteriorly to lengthen the palate as well as fracture of the hamulus, levator muscle repair, and closure of the nasal and oral mucosa in separate layers. It has been associated with a high incidence of fistula formation and growth disturbances, and has fallen out of favor in many centers.4 Vomer flaps can also be used to close hard palate defects. They can be either inferiorly or superiorly based and are useful in wide or bilateral clefts. Their use early in palatoplasty is controversial because of the risk of facial growth disturbance. Pharyngeal flaps are used to address poor speech in velopharygeal dysfunction.

The key concerns after cleft palate repair are: (1) airway monitoring, (2) control of postoperative bleeding, and (3) encouragement of early feeding. Bleeding can be controlled by meticulous intraoperative hemostasis and injection of local anesthetic that contains epinephrine, with packing of raw areas. Postoperative application of oxymetazoline (Afrin) can also reduce bleeding and is a popular adjunct. Oxymetazoline is a direct-acting sympathomimetic amine that acts on alpha-adrenergic receptors in the arterioles of the oronasal mucosa, resulting in decreased blood flow. Patients should be placed with the head gently elevated using pillows after cleft palate repair and not supine. Airway management involves continuous pulse oximetry and sedation is stopped as early as possible to minimize risk of respiratory compromise. Early feeding should be arranged, with liquid for the first 24 hours followed by a soft diet until day 10. Often, feeding can be the determining factor in discharge timing and all patients will stay overnight after surgery.1–4

Palatal fistulas by definition occur posterior to the incisive foramen. They most often occur at the junction of the soft and hard palates. The most common long-term complication after cleft palate repair is development of a palatal fistula, but rates are diverse (5–60%).1 They are likely to depend on many factors, including cleft severity, previous surgery, and surgical technique. The most common anatomic site is the junction of hard and soft palates.2 Fistulas can be treated surgically (with local or distant flaps) but alternatively may be managed nonsurgically with or without an obturator. The operative mortality in cleft palate repair is approximately 0.5%. Cleft palate repair can interfere with maxillary growth and does not normalize it. This can display as midface hypoplasia or problems with occlusion.3–5