by Michael Lee, MD

Cleft lip and palate is the most common congenital malformation of the head and neck.  It is a complex problem and requires multidisciplinary care and treatment.  This care is generally distributed among such fields as Plastic surgery, Oral surgery, Pediatrics, Psychiatry, Dentistry, Genetics, and of course Otolaryngology.  The incidence of cleft lip with or without cleft palate is 1/000 with a 2:1 male predilection.  The incidence also differs among ethnicities with Native Americans having the highest risk.  Isolated cleft palate has an incidence of 1/2000 with a 2:1 female predilection.  There is no variation among ethnicities with isolated cleft palate.

Cleft lip and palate can be divided into syndrome related or syndrome non-related abnormalities.  It is estimated that between 15 and 60% of all clefts are syndrome related.  Over 200 syndromes have been implicated in cleft lip and palate.  Syndrome-related clefts can be associated with single gene mutations, chromosomal aberrations, teratogens, or environmental influences.  In order for a child with a cleft to be placed in the non-syndromic category they must undergo normal growth and cognitive development, have no history of teratogenic or environmental factors, and have no other any head and neck or systemic anomalies.

It is difficult to discuss cleft lip and palate without at least a brief mention of the embryology.  Development of the nose, upper lip, and palate can be divided into two stages.  The first stage takes place during the fourth or fifth week of gestation.  During this phase the frontonasal process, which consist of bulk mesoderm with overlying ectoderm, proliferates and becomes the nose, upper lip, and premaxilla.  Lateral proliferation develops into lateral lip and the nasal ala.  The second phase begins during the eighth and ninth week of gestation and eventually produces the palate posterior to the incisive foramen.  During this phase mesodermal palatal shelves initially angled superior, migrate toward the midline and fuse.  Fusion begins at the incisive foramen and migrates posterior.  Any mishap during these phases can produce an anomaly of the lip or palate.

Cleft lip can be classified as unilateral or bilateral.  They can also be classified as complete, with extension into the nasal cavity, or incomplete with a bridge of soft tissue serving to divide.  Cleft palate can be classified as unilateral in which the larger of the palatal shelves is typically fused with the septum.  They can also be bilateral in which none of the palate bones are typically fused with the septum.  Cleft palate can be further classified as primary with the cleft anterior to the incisive foramen.  The defect is posterior to the incisive foramen in a secondary cleft.  If the cleft involves palate both anterior and posterior to the incisive foramen then it is classified as a complete cleft palate.  An incomplete cleft palate is used to describe a cleft of the secondary palate; most often this term refers to a submucosal cleft palate. 

A sound knowledge of cleft lip and palate anatomy is required prior to intervention and surgical repair.  The unilateral cleft lip typically has hypoplastic orbicularis fibers if incomplete, and if complete, the fibers are deficient medially and bulky laterally.  The columella is shortened in the unilateral cleft lip. The lateral crus of the lower lateral cartilage as well as the nasal ala is displaced inferior and lateral, leaving the dome flattened and rotated on the side of the cleft.  The bilateral cleft lip has an isolated bulge of soft tissue labeled the prolabium that is centrally located.  The prolabium, as well as the underlying premaxilla, appears protruded with regard to the hypoplastic maxillary segments.  Typically the orbicularis fibers are absent in the prolabium.  Nasal deformity is similar in bilateral cleft lip, with involvement of both lower lateral cartilages and ala.  When discussing cleft palate anatomy, it is important to remember that the hard palate is composed of the palatal shelves of the maxilla and that the posterior hard palate is composed of the horizontal plates of the palatal bones.  The soft palate is a fibromuscular fold consisting of the tensor veli palatini, levator veli palatini, palatoglossus, palatopharyngeus, and musculus uvulare muscles.  The primary function of the soft palate is to aid in speech and swallow.  Clefts involving the soft palate obviously preclude normal function in speech and swallow as well as proper eustachian tube dysfunction.  For this reason the otolaryngology community places myringotomy tubes in this population to assist in prevention of chronic middle ear effusion. 

There are many procedures that might be necessary for children with cleft lip and/or palate throughout their life.  Initially, they may require taping or lip adhesion to help mold the cleft lip or palate into a more narrow or symmetric deformity.  Cheiloplasty, which is repair of the cleft lip, is typically performed around three months of age.  If a child undergoes lip adhesion, this procedure is postponed until six months in an effort to allow mature scar to form.  There are many different methods of cheiloplasty, the most common in the United States being the Millard technique.  This procedure includes downward rotation to the medial segment with advancement of the lateral segment.  The scar is conveniently placed in the region of the natural philtral column.  Other methods include the Tennison-Randall repair, Hagedorn-LeMesurier repair, and Rose-Thompson repair.  Repair of the bilateral cleft lip is based off of the common themes of creating the philtrum from the prolabium and the lateral vermillion creating the tubercle.  Repair of the palate is termed palatoplasty and usually takes place around twelve months of age.  The earlier the repair takes place, the sooner the child will likely have improved velopharyngeal competence.  However, it is generally accepted that palatal repair may restrict maxillofacial growth and hence later repair is preferred.  There are multiple types of palatoplasty with one of the more common being the Bardach technique, of which there are many variants.  The Bardach repair includes bilateral palatal flaps based of the descending palatal artery.  Once the flaps are raised, the nasal mucoperiosteum is closed, the soft palate musculature repaired, and the oral mucoperiosterum approximated.  With a few adjustments, this procedure can be applied to a bilateral cleft palate as well.  The Wardill-Kilner-Peet repair is a V-Y advancement flap typically used for wide clefts and those of the secondary palate.  The Furlow technique is a double reversing Z-plasty typically used for narrow clefts of the secondary palate.  This procedure provides optimal effects on the soft palate as it realigns the levator sling, with lengthening of the palate to prevent velopharyngeal insufficiency.  Other procedures that children with cleft lip and palate may undergo include pharyngoplasty, alveolar bone grafting, rhinoplasty, and orthognathic jaw surgery. 

In conclusion, cleft lip and palate is the most common congenital malformation of the head and neck.  Treatment requires a multidisciplinary approach, to which the role of the Otolaryngologist is crucial.