Cleft lip and cleft palate

Cleft lip (CL) and cleft palate (CP) are the most common congenital orofacial deformities. A combination of genetic predisposition and in-utero exposure to teratogens (nicotine, alcohol, antiepileptic drugs) can arrest the fusion of the facial processes required for normal facial development. Failure of fusion of the maxillary prominence with the medial nasal prominence causes cleft lip (CL). Failure of fusion of the palatine prominences causes cleft palate (CP). Cleft lip and/or palate may be unilateral or bilateral and complete or incomplete. In addition to facial deformity, infants with CL and CP have feeding, hearing, speech difficulties, and defects in the dentition. Infants with cleft lips and/or palate require special feeding techniques (feeding in upright position, special feeding bottles) since they cannot effectively create negative sucking pressure. Treatment should be initiated as early as possible and may involve an interdisciplinary team of plastic surgeons, oral maxillofacial surgeons, otolaryngologists, pediatricians, and speech therapists. Nasoalveolar molding and lip taping are non-surgical techniques used to decrease the size of the lip/palatal defects and should be initiated early (at 2 weeks of age). Repair of the cleft lip is done at 3 months of age and of the cleft palate at 6 months of age with the aim of optimizing feeding and speech development without interrupting normal maxillofacial growth.

• Incidence
  • Cleft lip with/without cleft palate is common: 1 case in 1000 live births
  • Isolated cleft palate is less common: 1 case in 2000 live births
• Unilateral CL/CP is more common than bilateral CL/CP.
• Majority of cases are nonsyndromic.

References:^[1][2][3][4]

Epidemiological data refers to the US, unless otherwise specified.

The development of CL/CP is dependent on the interaction of environmental factors and genetic predisposition. ^[5]

• Genetic predisposition
  • Family history: multifactorial inheritance pattern (Mendelian inheritance is rare)
  • Part of genetic disorders
    • Pierre Robin sequence
    • Patau syndrome (trisomy 13)
    • Edwards syndrome (trisomy 18)
    • DiGeorge syndrome (22q11.2 deletion syndrome)
    • Loeys-Dietz syndrome: bifid uvula
• Environmental factors: exposure to teratogenic substances in utero
  • Nicotine and/or alcohol
  • Drugs: antiepileptics; (e.g., phenytoin, sodium valproate, carbamazepine, phenobarbital), folate antagonists (e.g., methotrexate, trimethoprim), and excessive vitamin A intake during pregnancy

Cleft lip and palate involves a disrupted fusion of the 5 embryonic facial prominences (the midline frontonasal prominence, the bilateral maxillary prominences, and the bilateral mandibular prominences) and results in congenital orofacial deformities. ^[6]

• Cleft lip
  • Partial or total failure of primary palate formation during the 6–7^th week of development
  • Failed fusion of the maxillary prominences and medial nasal prominences at the midline
• Cleft palate
  • Failed formation of the secondary palate during the 8–12^th week of development
  • Failed fusion of either the lateral palatine processes (palatine shelves) or of the palatine shelves with the nasal septum and/or primary palate

Partial or total failure of primary palate formation leads to cleft lip. Failed formation of the secondary palate leads to cleft palate.

Facial features ^[2][7]

CL/CP may be unilateral or bilateral, complete or incomplete.

Cleft lip

• Microform cleft lip: slight, incomplete cleft characterized by a notch on the vermillion border of the upper lip (unilateral)
• Incomplete cleft lip: cleft on the upper lip that does not extend into the nostril (unilateral/bilateral)
• Complete cleft lip
  • Cleft on the upper lip that extends into the nostrils (unilateral/bilateral)
  • Cleft palate is more commonly associated with complete than incomplete cleft lip
• Unilateral cleft lip: the orbicularis oris inserts into the nasal ala on the cleft side and the columella on the unaffected side
• Bilateral cleft lip: the orbicularis oris inserts into the nasal alae bilaterally

Cleft palate

• Incomplete cleft palate: clefting only of the secondary palate (anterior or posterior to the incisive foramen)
• Complete cleft palate
  • Cleavage of the entire hard palate, soft palate, and the uvula (anterior and posterior to the incisive foramen)
  • Often associated with cleft lip
• Bifid uvula
  • A split or forked uvula, typically containing less muscle tissue than a normal uvula.
  • Least severe form of cleft palate
• Submucosal cleft palate (occult cleft palate): muscular and/or bony palatal defect that is masked by intact palatine mucosa

Other features ^[8][9]

• Feeding difficulties: depends on the type and severity of the cleft
  • Bifid uvula: may cause nasal regurgitation
  • Cleft lip
    • Sucking difficulties may occur.
    • Minimal feeding difficulties
  • Cleft Palate
    • Sucking difficulties
    • Nasal regurgitation of milk
    • Choking/coughing during feeds
    • Excessive aerophagia
• Speech difficulties: hypernasal, unintelligible speech due to velopharyngeal insufficiency (a structural disorder that causes the inability to form a seal between the nasopharynx and oropharynx and that is characterized by hypernasal speech, which may impair intelligibility)
• Dentition defects (in CP): due to clefts creating gaps in the maxilla
• Hearing loss: due to recurrent/persistent otitis media with effusion (OME)

• Prenatal
  • CL/CP may be diagnosed on prenatal ultrasound (after 12 weeks of gestation)
  • If detected prenatally, amniocentesis for karyotyping is offered, to detect other chromosomal abnormalities
• Postnatal: clinical diagnosis; children with a submucosal cleft palate may present in later life with abnormal speech and/or OME

References:^[10]

Approach ^[11][12]

• Management requires an interdisciplinary approach involving oral maxillofacial surgeons, plastic surgeons otolaryngologists, pediatricians, and speech therapists.
• A cleft lip or palate should always receive surgical repair.
• Speech assessment at 12–14 months and therapy of velopharyngeal insufficiency

Conservative measures before surgery ^[13]

• Proper feeding techniques: feeding in upright position to prevent nasal regurgitation; use of specialized feeding bottles ; frequent burping
• Nasoalveolar molding: Use of a custom made orthodontic prosthesis to bridge and reduce the palatal gap and passively mold the maxillary, palatal, and nasal structures into a normal shape
• Nasal stent: to lift the drooping nostril and shape the nose
• Lip taping: use of adhesive tape to reduce the defect; makes definitive surgery easier
• Lip adhesion: suturing the edges of the cleft lip, in conjunction with NAM can be done in infants with complete CL/CP who are not responding well to lip taping

Surgical repair ^[14]

• Cleft lip repair (cheiloplasty)
  • Goals: achieving normal lip contour and nose, improve oral competence
  • Timing: at age 3 months, surgery is usually staged with cleft lip being the first surgery and cleft palate done at a later time due to risk of surgery to infant
  • Tympanostomy tubes are placed at the same sitting: in children with OME causing hearing loss/recurrent infections
• Cleft palate repair (palatoplasty) ^[15]
  • Goals: closure of the defect, optimal speech development, and normal maxillofacial growth
  • Timing: at age 6–9 months
• Further surgery is often required as the child grows older.