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Various craniofacial abnormalities result from maldevelopment of the 1st and 2nd visceral arches, which form facial bones and ears during the 2nd mo of gestation. These deformities include cleft lip and cleft palate; Treacher Collins (mandibulofacial dysostosis), Goldenhar's (oculoauriculovertebral dysplasia or hemifacial microsomia), Waardenburg's, and Pierre Robin syndromes; hypertelorism; and external and middle ear deformities (see
Table 1: Congenital Craniofacial and Musculoskeletal Abnormalities: Common Craniofacial Syndromes ). Most infants with craniofacial abnormalities have normal intelligence.
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Table 1
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Common Craniofacial Syndromes
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Syndrome
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Typical Findings
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Waardenburg's syndrome
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Deafness, partial albinism (white forelock usually), heterochromic iris, laterally displaced medial canthi
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Pierre Robin syndrome
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Micrognathia with glossoptosis, mandibular hypoplasia, cleft soft palate
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Treacher Collins syndrome
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Malformed external ear, mandibular and malar hypoplasia, antimongoloid slant of the palpebral fissures, coloboma of the lower eyelid, conductive hearing loss
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Goldenhar's syndrome (oculoauriculovertebral dysplasia)
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Facial asymmetry, unilateral malformed external ear with preauricular tags and sinuses, conductive hearing loss, microphthalmia, epibulbar lipodermoid, macrostomia with mandibular hypoplasia, vertebral abnormalities
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Velocardiofacial syndrome
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Cleft palate, hypernasal speech, cardiac abnormalities, typical facies, learning disabilities
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Cleft palate
and cleft lip:
The most common 1st arch deformities are cleft palate and cleft lip, which occur in 1/700 to 800 births. Both environmental and genetic factors are thought to contribute. Prenatal maternal use of tobacco and alcohol may increase risk. Having one affected child increases risk of having a second one. Folic acid, taken just before becoming pregnant and through the 1st trimester, decreases the risk.
The cleft may vary from involvement of only the soft palate to a complete fissure of the soft and hard palates, the alveolar process of the maxilla, and the lip. The mildest form is a bifid uvula.An isolated cleft lip can occur.
A cleft palate interferes with feeding and speech development. Goals of treatment are to ensure normal feeding, speech, and maxillofacial growth and to avoid formation of fistulas. Early treatment, depending on the specific abnormality, consists of specially designed bottle nipples (to facilitate flow) or dental appliances (to occlude the cleft so suckling can occur) and a feeder that can be squeezed to deliver formula. Ultimate treatment is surgical closure; however, timing of surgery, which may interfere with growth centers around the premaxilla, is somewhat controversial. For a cleft palate, a 2-stage procedure is often done. The cleft lip and soft palate are repaired during infancy (at age 3 to 6 mo). Then, the residual hard palate cleft is repaired at age 15 to 18 mo. Surgery can result in significant improvement, but if deformities are severe or treatment is inadequate, patients may be left with a nasal voice, compromised appearance, and a tendency to regurgitate. Dental and orthodontic treatment, speech therapy, and counseling may be required.
Deformities characterized
by a small mandible:
Pierre Robin syndrome and Treacher Collins syndrome are characterized by glossoptosis (a tongue that falls to the back of the throat) and respiratory problems as well as micrognathia (a small mandible). A cleft palate as well as conductive hearing loss may be present. Feeding can be difficult, and sometimes cyanosis develops because the tongue is posterior and may obstruct the pharynx. Prone positioning during feeding may help, but uncoordinated swallowing may require nasogastric gavage feedings or a gastrostomy tube. If cyanosis or respiratory problems persist, tracheostomy or surgery to affix the tongue in a forward position (eg, sewing it to the inner lower lip) may be required. Otologic evaluation is indicated.
Agenesis
of the jaw:
Congenital absence of the condyloid process (and sometimes the coronoid process, the ramus, and parts of the mandibular body) is a severe malformation. The mandible deviates to the affected side, resulting in severe malocclusion; the unaffected side is elongated and flattened. Abnormalities of the external, middle, and inner ear; temporal bone; parotid gland; masticatory muscles; and facial nerve often coexist.
X-rays of the mandible and temporomandibular joint show the degree of underdevelopment and distinguish agenesis from other conditions that result in similar facial deformities but do not involve severe structural loss.
Treatment consists of reconstruction with autogenous bone grafting (costochondral graft) and is done promptly to limit progression of facial deformity. Often, mentoplasty, onlay grafts of bone and cartilage, and soft-tissue flaps and grafts further improve facial symmetry. Distraction osteogenesis is being increasingly used; an osteotomy is done, and a distraction (separator) device is attached to both pieces. Over time, the distance between the 2 pieces is widened, and new bone grows in between to enlarge the bone. Orthodontic treatment in early adolescence helps correct malocclusion.
Congenital
ear malformations:
Malformed pinna (microtia) and external auditory canal atresia, which causes conductive hearing loss, involve the external ear. These malformations, which frequently coexist, are often identified at or soon after birth. Occasionally, school-based screening tests identify a partially occluded external auditory canal in children with a normal pinna.
Hearing tests (see Hearing Loss: Physical examination) and CT of the temporal bone are necessary to evaluate possible additional bony malformations. Treatment can include surgery and a bone-conduction hearing aid, depending on whether the malformation is unilateral or bilateral; whether it affects hearing, learning, and social development; and whether complications (eg, facial nerve involvement, cholesteatoma, otitis media) are present. Surgery may include pinna reconstruction, the creation of an external auditory canal, tympanic membrane, and ossicles, or both.
Last full review/revision November 2005
Content last modified November 2005
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