**7.1. Robin anomalad**

are absent. The ethmoid bone (that set the interorbital distance) is hypoplastic. The secondary palate may or may not be involved. MCL with hypertelorism (also known as "median cleft face syndrome" or "frontonasal dysplasia") is characterized by the presence of a bifid nose and cranium bifidum occultum, as well as of the premaxilla, while the brain is normal in most cases. **Diagnosis:** The defect, involving both the upper lip and the palate, is better seen in axial scans of the palate (**Figure 17**). A useful hint in this process is the visualization of the tongue in a position within the oral cavity, which is higher than normal. The sonographer should be alerted to a possible pitfall in the diagnosis of MCL because sometimes the defect may be

**Prognosis and obstetrical management:** Prognosis depends entirely on the association with other anomalies. MCL syndrome is associated in 80% of cases with normal intelligence. Radical cosmetic surgery is required. If alobar holoprosencephaly present, it is uniformly lethal [42].

**Incidence:** 2% of all pediatric teratomas occur in the nasopharyngeal area (including oral,

**Pathology:** Tumors arise mainly from the sphenoid bone; they rarely arise from other areas (the hard and soft palate, the pharynx, the tongue, and jaw). These tumors grow into the oral or nasal cavity or intracranially. Obstruction of the mouth is responsible for polyhydramnios. Most tumors are benign, consisting histologically of tissues derived from any of the three germinal layers. They can fill the mouth and airways and lead to acute asphyxia immediately

**Ultrasound diagnosis:** Solid tumor arising from the sphenoid bone, hard and soft palate, the pharynx, the tongue, and the jaw. The tumor may grow into the oral or nasal cavity or intracranially. Calcifications and cystic components may also be noticed. The differential diagnosis will include neck teratomas, encephaloceles, conjoined twins, and other tumors of the facial

**Associated abnormalities:** This is a sporadic condition, with no increased incidence of chromosomal defects or genetic syndromes; only 6% of these tumors have associated anomalies, and the facial ones being attributed to the mechanical effects of the tumor on developing

**Investigations:** Scans every 4 weeks to monitor the growth of the tumor and assess the amniotic fluid. If polyhydramnios develops, amniodrainage may be balanced. Fetal MRI is recom-

**Prognosis:** It depends on the size of the lesion and the involvement of vital structures. The lesions are usually very large, and the polyhydramnios associates a poor prognosis. The major cause of neonatal death is asphyxia due to airway obstruction. Surgical resection is possible at

mended at 32 weeks to assess the spatial relation of the tumor to adjacent structures.

times. There are no reported cases of malignancies [46–49].

tonsillar, and basicranial areas). The majority of cases occur in newborn [43, 44].

structures. Polyhydramnios (due to pharyngeal compression) is usually present.

masked by the tongue, giving a false impression of an intact palate [41].

**Definition:** A teratoma that arises from the oral cavity or pharynx.

**6.2. Epignathus**

108 Congenital Anomalies - From the Embryo to the Neonate

after birth [44].

structures [45].

**Synonyms:** Cleft palate, micrognathia and glossoptosis, and Pierre Robin syndrome.

**Definition:** This anomaly is associated with micrognathia and glossoptosis, with a posterior cleft palate or a high arched palate.

**Incidence:** The frequency is 1:30,000 [50].

**Etiology:** In 40% of the cases, the anomaly is isolated and mostly sporadic, although sometimes familiar cases suggest both autosomal recessives and autosomal dominant patterns of transmission. It is most frequently seen in association with other anomalies or with recognized genetic and nongenetic syndromes [51].

**Embryology:** The mandible starts at the point in which the two mandibular prominences join to delimit the inferior part of the stomodeum. The fusion of the three palatine processes forms the palate. Finally, the frontonasal prominence creates the median, and the maxillary processes create the two lateral ones. It is apparent that the three components of this defect are related to one another. Possibly, an early hypoplasia of the mandible creates this defect, as it leads to the tongue being displaced toward the posterior region, which prevents the posterior palatine processes to close as they should in a normal situation [52].

**Associated anomalies:** The Robin anomaly is found as an isolated lesion in 39% of all patients. In 36%, one or more associated anomalies are present. In 25% of patients, a known syndrome is found.

Robin anomaly is to be suspected when polyhydramnios is associated with micrognathia (**Figure 18**). Congenital heart disease occurs in 10% of affected neonates, so fetal echocardiography is recommended [53].

**Prognosis:** The Robin anomaly is a neonatal emergency in many cases. Glossoptosis may lead to the obstruction of the airways and suffocation.

It is mandatory that a pediatrician be present in the delivery room and be prepared to intubate the infant. Karyotype should be considered [54].
