Cleft lip and cleft palate occur in twice as many males as females; isolated cleft palate is more common in females.
Causes
Cleft lip or palate can occur as part of another chromosomal or Mendelian abnormality (more than 150 have been identified); however, exposure to teratogens during fetal development or a combination of genetic and environmental factors may also produce these defects.
Cleft lip with or without cleft palate occurs in about 1 in 1,000 births among Whites; the incidence is higher among Asians (1.7 in 1,000) and Native Americans (more than 3.6 in 1,000) but lower among Blacks (1 in 2,500). A positive family history is a risk factor for cleft defects.
Signs and symptoms
Congenital defects of the face usually occur in the upper lip. They range from a simple notch to a complete cleft from the lip edge through the floor of the nostril, on either side of the midline, but rarely along the midline itself.
A cleft palate may be partial or complete. A complete cleft includes the soft palate, the bones of the maxilla, and the alveolus on one or both sides of the premaxilla. A double cleft runs from the soft palate forward to either side of the nose, separating the maxilla and premaxilla into freely moving segments. In Pierre Robin syndrome, the tongue is displaced due to micrognathia. The tongue prevents the palate from fusing. Glossoptosis coexists with cleft palate.
Isolated cleft palate is more commonly associated with other congenital defects than isolated cleft lip or cleft lip and cleft palate.
Diagnosis
A typical clinical picture confirms the diagnosis. Cleft lip with or without cleft palate is obvious at birth; occasionally, more severe defects may be seen with diagnostic prenatal ultrasonography. Isolated cleft palate may not be detected until a mouth examination is done or until feeding difficulties develop.
Treatment
Treatment consists of surgical correction, but the timing of surgery varies. Some plastic surgeons repair cleft lips within the first few days of life to make feeding the baby easier. However, many surgeons delay lip repairs for 8 to 10 weeks (sometimes as long as 6 to 8 months) to allow time for maternal bonding and, most important, to rule out associated congenital anomalies.
Cleft palate repair is usually completed by the 12th to 18th month. Still other surgeons repair cleft palates in two steps, repairing the soft palate between ages 6 and 18 months and the hard palate as late as age 5 years. In any case, surgery is performed only after the infant is gaining weight and is infection-free.
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