The Syndromic Child (May,1996)

THE SYNDROMIC CHILD
SOURCE: Dept. of Otolaryngology, UTMB, Grand Rounds
DATE: May 8, 1996
RESIDENT PHYSICIAN: Greg Young, M.D.
FACULTY: Ronald W. Deskin, M.D.
SERIES EDITOR: Francis B. Quinn, Jr., M.D.

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"This material was prepared by resident physicians in partial fulfillment of educational requirements established for the Postgraduate Training Program of the UTMB Department of Otolaryngology/Head and Neck Surgery and was not intended for clinical use in its present form. It was prepared for the purpose of stimulating group discussion in a conference setting. No warranties, either express or implied, are made with respect to its accuracy, completeness, or timeliness. The material does not necessarily reflect the current or past opinions of members of the UTMB faculty and should not be used for purposes of diagnosis or treatment without consulting appropriate literature sources and informed professional opinion."

The syndromic child is at risk for several problems within the Otolaryngologist's range of expertise. Anatomic anomalies and functional deficiencies often compromise the upper airway, hearing, and speech of these patients. Occult findings, usually in the neck, may lead to severe consequences if unrecognized.

Terms:

Malformation-

A malformation is a “morphologic defect of an organ, part of an organ, or a larger area of the body resulting from an intrinsically abnormal developmental process. The most common types of malformations are due to incomplete morphogenesis, such as hypoplasia (e.g. microcephaly), incomplete closure (e.g. cleft palate), or incomplete separation (e.g. syndactyly). Malformations initiated late in fetal development are simple, while those initiated early in organogenesis are more complex and severe.1

Deformation-

A deformation is an abnormal form or position of a portion of the body (e.g club foot, congenital hip dislocation). They occur late in fetal development, and are caused by intrauterine mechanical forces that restrict the movement of the developing fetus. Conditons that may restrict fetal movement include a small maternal size, amniotic tear, bicornuate uterus, and twin fetuses. In addition, fetal malformations of the central nervous system or urinary tract may also lead to deformations, due to partial paralysis of the legs or insufficient amniotic fluid, respectively. Deformations may spontaneously improve postnatally, when the restriction on movement is no longer present.1

Disruption-

A disruption is a defect due to an interference with an otherwise normally developing organ or region of the body. The in-utero amputation of a finger or limb due to an amniotic band is a disruption. Unlike malformations and deformations, disruptions usually occur sporadically, with no increased recurrence risk. 1





Comparison of Malformations, Deformations, and Disruptions:

                       Malformation    Deformation          Disruption

Timing of Insult          embryo          fetus                fetus

Level of Insult           organ           region               region

Mortality                 +               -                    -

Spontaneous Correction    -               +                    -

Recurrence Risk           Higher          Lower                Rare

Frequency in Neonates     3%              2%                   Rare



- modified from table 3-15 of Pediatric Otolaryngology, Bluestone, Stool,

Kenna, third edition, 1995.

Sequence-

A sequence occurs when a single developmental defect results in a chain of secondary defects, which may, in turn, lead to tertiary defects. The result is a variably expressed group of defects, all of which can be traced back to the original event. For example, the primary defect in Pierre Robin syndrome is mandibular hypoplasia, which results in posterior displacement of the tongue, which precludes closure of the palatal aches. Both single malformations and sequences may occur in isolation, or as part of a group of malformations.1

Syndrome-

Syndromes are groups of anomolies which contain multiple malformations and/or sequences. The malformations and sequences are variably expressed in a syndrome, such that a given anomaly may be incompletely expressed or absent in certain individuals with the syndrome. Single malformations that are unique to a syndrome, and that are always expressed in that syndrome, are very rare. Therefore, making the diagnosis of a syndrome depends on recognizing the overall pattern of the anomalies. In the more common syndromes, the frequency and range of expression of various malformations and sequences are known.1

Syndrome vs. Sequence-

In syndromes, the pathogenetic relationship of the group of anomalies is frequently not understood. By contrast, the entire cascade of events is often known in a sequence. A sequence may have multiple known causes (e.g. Pierre Robin), whereas a syndrome can often be traced to a single genetic malformation (e.g. Down syndrome). In sequences, there is one primary defect causing a cascade of secondary anomalies. In syndromes, there are often multiple primary defects resulting in several cascades of embryonically noncontiguous anomalies. One or more sequences may be associated with various syndromes (e.g. Pierre Robin sequence is often seen in Stickler syndrome).1

Associations-

An association is the occurrence in multiple patients of a group of anomalies not known to be a sequence or syndrome(e.g. CHARGE, VATER). It is not a specific disorder or diagnosis. Its main utility as a designation is to alert clinicians to search for other possible components of the constellation in a patient with one or more anomalies. 2

Minor Anomalies of the Face

Minor anomalies are those defects without serious medical or surgical significance. Examples of minor anomalies of the face include epicanthic folds, coloboma, small or protuberant ears, small nares, and bifid uvula. Almost half of all known minor anomalies occur on the face. These anomalies may be of cosmetic concern since they are often conspicuous.

Certain minor anomalies are quite common in many syndromes, and therefore often aid in their diagnosis. For example, the upslanting palpebral fissures, epicanthic folds, low nasal bridge, small nose, and protruding tongue of Down syndrome provides a typical appearance that readily suggests the diagnosis.1

While isolated minor anomalies are quite common and occur in 15% of the general population, 90% of patients with 3 or more minor anomalies also have a major anomaly . Therefore, infants with 3 or more minor anomalies should be carefully evaluated for occult renal, cardiac, or vertebral anomalies.1

Idiopathic mental retardation is also associated with multiple minor anomalies. A study of patients with idiopathic mental retardation showed that more than 40% of these patients had 3 or more anomalies, 80% of which were minor. Therefore, patients with 3 or more anomalies should be monitored closely for appropriate mental development. 1

Syndrome Diagnosis

The diagnosis of a syndrome begins with a careful history and physical examination. Photographs help with documentation and chromosome studies may be used to confirm certain syndromes.

The history should include the mother's age, exposure to toxins, and previous abortions. Paternal age, parent consanguinity, and family history are also important. Maternal Factors:

Advanced age- increased risk of trisomies (21, 13, 18)

Exposure to toxins- fetal alcohol syndrome, fetal hydantoin syndrome, warfarin syndrome

Previous abortions- X-linked dominant disorders, balanced translocation carriers

Advanced Paternal Age- increased risk of new mutations and dominant conditions (e.g. Marfan, Crouzon, Treacher Collins, Apert)

Consanguinity- associated with autosomal recessive defects

Positive Family History- associated with chromosomal or monogenic disorders

Management of Children with Craniofacial Syndromes:

The aesthetic, functional, and psychological ramifications of craniofacial anomalies in children are immense, and span the range of expertise of several medical and surgical specialties. As such, a team approach is essential to the management of these patients. The otolaryngologist typically is responsible for evaluation and management of the upper airway, hearing, and speech in these patients.

Airway:

Children with craniofacial anomalies present a variety of airway challenges. The airway problems which may occur in these children change as the child grows, but each may cause significant morbidity, and in some cases, mortality.

Neonatal Nasal Airway Obstruction-

Neonatal nasal airway obstruction may occur in infants less that 3 months old who have bilateral choanal atresia, midfacial hypoplasia (Crouzon, Apert), or frontal nasal dysplasia (nasal encephalocele). Because infants are obligate nasal breathers, respiratory distress and asphyxia may occur. Affected infants have paradoxical cyanosis, whereby cyanosis occurs at rest, and only resolves when the infant is crying (and therefore mouth breathing). Treatment consists of securing an oral airway in place until 2-3 months of age, when the child learns to mouth breathe.1

Neonatal Oral Airway Obstruction-

Neonatal oral airway obstruction may occur in children with mandibular hypoplasia or retrognathia, as the associated glossoptosis (posteroinferior displacement of the tongue) results in oropharyngeal obstruction. Mandibular anomalies and glossoptosis are more likely to cause symptomatic obstruction in patients with a cleft palate(e.g. Pierre Robin sequence). Treatment is usually insertion of a nasopharyngeal airway, or tracheotomy (performed over a rigid bronchoscope). Infants may sometimes be kept in the prone position to provide an adequate airway, allowing the tongue to fall anteriorly. Suturing the tongue to the lower lip has been advocated in the past. Mandibular growth reduces glossoptosis with time, and by 6 months of age, this type of airway obstruction has usually resolved. Decannulation is usually performed at this time. However, if a cleft palate is present, decannulation may be delayed until after its repair.1

Obstructive Sleep Apnea-

Obstructive sleep apnea may occur in children with narrowed nasopharygeal airways. In addition to children with enlarged adenoids, those with posterior displacement of the midface (Crouzon, Apert) may occlude their nasopharygeal airway when in the supine position. The resulting obstructive sleep apnea in both groups of patients may be successfully treated with adenotonsillectomy.

Older children with retrognathia (Treacher Collins) and snoring with obstructive symptoms may also benefit from tonsillectomy. If unsuccessful, sliding mandibular osteotomies are sometimes performed in mid-adolescence.

Uvulopalatopharyngoplasty (UPPP) is contraindicated in patients with glossoptosis and a history suggestive of obstructive symptoms. In general, surgery for velopharyngeal incompetence (VPI) should not be performed on patients at risk for obstructive sleep apnea. Severe obstructive sleep apnea and cor pulmonale have been documented after UPPP in these patients.

Tracheostomy may be necessary in some children with OSA, either as an initial treatment in severe cases to prevent asphyxiation, or as a last resort after adenotonsillectomy, partial base of tongue or supraglottic fold excision, and/or sliding mandibular osteotomies have failed to relieve the obstruction.1

Chronic Nasal Obstruction->

Patients with a unilateral cleft of the primary palate have a combination of nasal anomalies that results in bilateral nasal obstruction.

1) The dome of the ipsilateral lower lateral cartilage is lower smaller, and retroposed, with a widened angle between the medial and lateral crura.

2) The ipsilateral upper lateral cartilage is flatter

3) The ipsilateral lateral crus is flatter

4) The alar base is displaced downward against an underdeveloped maxilla

5) The nasal floor is wider

6) The columella and cartilagenous septum are deviated to the contralateral side

7) The posterior septum is deviated to the ipsilateral side

8) The nasal tip is deviated to the contralateral side

If the soft tissue collapse is not significant, septoplasty alone may improve the nasal airway in these patients. Conservative removal of a caudal strip of cartilagenous septum, and more aggressive removal of the vomer and nasal spine is advocated.

Another cause of nasal obstruction in patients with craniofacial anomalies is nasal mucosal edema. This may result from an oronasal fistula, heterotopic tooth eruption in the floor of the nose, or sinusitis. Medical or surgical treatment of these conditions may improve the nasal airway.1

Surgical Airway Maintenance in Children with Craniofacial Anomalies-

The surgical airway in children with craniofacial anomalies may be maintained with naso- or oro-tracheal intubation, or with tracheostomy. Tracheostomy is somewhat less common today due to improvements in intubating equipment and techniques (e.g. flexible endoscopes, optical stylets), and the use of miniplates instead of IMF for mandibular osteotomies. However, tracheostomy should still be performed whenever difficulties with either primary endotracheal intubation or urgent postoperative re-intubation are anticipated.3

The ideal method of airway maintenance varies depending on the patient's anatomic restrictions, and the surgery to be performed. Nasotracheal intubation may not be possible in patients who have undergone cleft palate repair, unless the lateral ports of the palatopharyngoplasty flap are of sufficient size. In patients with severe retrognathia and TMJ ankylosis, nasal intubation or bronchoscopy followed by tracheostomy in usually indicated. If retrognathia occurs with cervical spondylosis, local tracheostomy without prior airway control may be necessary. In general, however, tracheostomies in children with craniofacial anomalies should be performed with prior airway control using bronchoscopy or endotracheal intubation.

The anatomic anomaly most often associated with difficult airway management is mandibular hypoplasia.3 Children born with mandibular hypoplasia (e.g. Pierre Robin sequence, Treacher Collins syndrome, Goldenhar's syndrome) often require laryngoscopy or intubation. This may be due to primary respiratory symptoms, or because general anesthesia is required to correct a congenital anomaly. Visualization of the vocal cords can be difficult or impossible with standard intubating techniques due to anatomic features associated with mandibular hypoplasia. These include a prominent maxilla or maxillary teeth, glossoptosis, a small oral cavity which results in a relative macroglossia, and trismus due to TMJ problems. As a result of the posterior displacement of the tongue, the larynx appears to be located more anteriorly during laryngoscopy, precluding its visibility.

Method of Intubation-

A method of intubation has been developed by Handler and Keon that minimizes the anatomic difficulties associated with the hypoplastic mandible.3 The following instruments are required, in addition to the usual pediatric airway set:

1) appropriate size endotracheal tube with proximal connector removed, which has been coated with a water soluble lubricant

2) lubricated 2.7 mm diameter telescope

3) 9-cm pediatric Jackson anterior commissure laryngoscope

4) laryngeal alligator forceps

After placing the child in the sniffing position, a 9-cm pediatric Jackson anterior commissure laryngoscope is inserted along the right side of the tongue. This particular laryngoscope is recommended because

1) the straight enclosed barrel prevents protrusion of the tongue into the line of sight

2) the narrow profile promotes easier access to the laryngeal inlet, and

3) suctioning is easily accomplished.

When the posterior third of the tongue is reached, the proximal end of the laryngoscope is moved far right, and the distal tip is directed to the midline and advanced. Using this method instead of the usual "midline tongue" approach, the fulcrum action of the tongue on the laryngoscope is avoided, and the needed anterior angulation of laryngoscope is attained. The laryngoscope is then used to lift the epiglottis, and further advancement is accomplished after the larynx is externally manipulated both posteriorly and to the left. Once the vocal cords are in view, the prepared endotracheal tube is inserted into the laryngoscope and passed through the cords. The telescope may be used as an optical stylet if insertion is difficult. The telescope is removed, and the proximal end of the endotracheal tube is grasped with the alligator forceps.

The laryngoscope is then carefully removed, and the forceps is used to hold the endotracheal tube in place. The proximal connector is then reattached to the endotracheal tube, and placement is confirmed in the usual fashion. 3

Hearing Loss

Normal hearing is required for proper development of language skills. Even mild degrees of hearing loss may impair learning. Children with craniofacial anomalies are at high risk for congenital and acquired hearing loss. Often, however, the detection of hearing loss in these children is delayed because their slower learning is attributed to their syndrome. Unusual appearance is often erroneously equated with mental retardation. Both congenital and acquired hearing loss in these patients is usually conductive. Any sensorineural component in most types of craniofacial anomalies is thought to be coincidental. An exception is the congenital sensorineural hearing loss associated with Waardenburg syndrome.

Congenital Hearing Loss-

Congenital hearing loss is commonly seen with microtia, because of the often associated external canal atresia. Microtia is common with Treacher-Collins syndrome and hemifacial microsomia. Patients with canal atresia often have obliteration of the middle-ear cleft, thereby precluding surgery. Hearing in these patients, however, often is much improved with a bone conduction hearing aid. Surgery is usually not performed on patients with a normal hearing ear, but CROS hearing aids may improve auditory rehabilitation in these patients.

Congenital hearing loss without microtia may be due to ossicular deformity or fixation. Ossicular anomalies are often associated with an abnormal appearing tympanic membrane (small, oblique, poor landmarks). Ossicular surgery is often helpful in these patients, but increased caution should be exercised due to the greater incidence of facial nerve dehiscence and abnormal location.1

Acquired Hearing Loss-

Acquired hearing loss in patients with craniofacial anomalies is usually associated with eustachian tube dysfunction (ETD). Middle ear effusion, retraction, atelectasis, and cholesteatoma are all seen in these patients as a consequence of ETD. Patients with secondary cleft palates and midface craniosynostosis are most commonly affected. Those with Apert syndrome (acrocephalosyndactyly) may have abnormal eustachian tube cilia, which may exacerbate the ETD.

Children with secondary cleft palates and midface craniosynostosis rarely respond to antibiotics, and usually require tympanostomy tube placement for ETD. Often, tubes will be needed until early to mid adolescence. Unilateral jugular dehiscences may be more common in patients with craniosynostosis, so careful preoperative examination should be performed in these patients. In addition, poor eustachian tube function in these patients precludes successful tympanoplasty until mid to late adolescence.1

Speech Disorders:

Hypernasality-

Cleft palate repair often leads to velopharyngeal incompetence (VPI) and an associated hypernasal speech. Hypernasality also characterizes "deaf speech", observed with craniofacial anomalies and a hearing loss of more than 30dB. Hypernasality can often be substantially reduced with speech therapy. If the child is at least 5 years old and speech therapy has failed, palatopharyngoplasty (UPPP) is often performed with good results. Again, UPPP should not be performed on patients with glossoptosis and obstructive symptoms.1

Hyponasality-

Hyponasality is due to nasal airway obstruction, and is commonly seen in patients with craniofacial anomalies that involve a posterior displacement of the midface. Similar hyponasality occurs with bilateral choanal atresia and iatrogenic velopharyngeal atresia (e.g. due to UPPP). These patients often respond to adenoidectomy, and repair of choanal atresia if present.

Hoarseness-

Hoarseness in common in patients with VPI due to vocal nodules that develop in response to compensatory increased laryngeal activity. The treatment of choice is correction of the VPI. Hoarseness may also occur after nasotracheal intubation.

Common Syndromes and Sequences in Otolaryngology:

Pierre Robin Sequence:

Pierre Robin sequence is the combination of micrognathia, cleft palate, and glossoptosis, which occurs in about 1 in 8,500 births. It is seen with a variety of disorders, including those due to monogenic or chromosomal abnormalities, teratogens, and disruptions. One fourth of children with Pierre Robin sequence have a specific syndrome, another one third have multiple anomalies but no specific syndrome, and the remaining 40% occur in isolation. The syndrome most commonly seen in patients with Pierre Robin sequence is Stickler syndrome (about 12%). Because of the ocular problems associated with Stickler syndrome (myopia, retinal detachment due to connective tissue disorder), patients with Pierre Robin sequence should have a careful eye examination. Ear, heart, and limb anomalies are also seen with increased frequency in Robin sequence children.

The basic defect in Robin sequence is thought to be mandibular hypoplasia which may occur by at least four different mechanisms. Oligohydromnios decreases fetal movement, and may restrict mandibular growth by compressing the chin against the chest. Hypotonia may inhibit mouth opening and thereby restrict mandibular exercise. Systemic growth deficiencies may cause intrinsic mandibular hypoplasia. Connective tissue disorders may cause intrinsic mandibular hypoplasia and inhibit palatal closure.

The resulting mandibular hypoplasia causes a posterior displacement of the tongue. A wide U shaped cleft palate is caused by the tongue partially interposing between the palatal folds. Micrognathia results in decrease support for the tongue, which leads to glossoptosis (postero-inferior position of tongue).2

Airway and hearing problems are common in patients with Robin sequence.

Airway:

Glossoptosis causes a ball valve effect in the posterior pharynx, allowing air to excape, but not enter the lungs. This, in turn, leads to episodic cyanosis and sternal retractions, worse in the supine position. Respiratory difficulty frequently occurs within the 1st week of life. Asphyxia has occurred from the tongue becoming lodged in the cleft palate, thereby occluding the nasopharyx. Failure to thrive is common in these patients, and can often be reversed by placement of a nasopharyngeal airway. Cor pulmonale may develop in severe cases, and is treated with nasopharyngeal airway placement or tracheostomy. 2

Hearing:

Otitis media is common in these patients, and is due to eustachian tube dysfunction, complicated by the cleft palate.

Feeding:

Poor feeding is common, and probably results from lack of tongue control.

Trisomy 21 syndrome(Down Syndrome)

Down syndrome is the most common of all malformation syndromes. In 1866, Langdon Down described a condition that he called "mongolian idiocy". Down syndrome occurs in about 1/650 live births. The majority of trisomy 21 conceptions end in spontaneous abortions.2

The syndrome is due to a nondisjunction (95%) of chromosome 21 or translocation (5%) of the q22 segment to another chromosome. The recurrence rate for nondisjunction type Down syndrome is about 1%, and for translocation type is 2-10% (except is 100% for G/G(21/21) translocation).4

Average IQ is 30-40, and Down syndrome occurs in about 15% of patients institutionalized for mental retardation. Average life span is 35 years, with death due to congenital heart disease, leukemia, and pneumonia in childhood, and Alzheimer's and poor immunity in adulthood. Prevalence increases with maternal age.5

Hall studied the clinical features of these patients extensively, and developed the Ten Cardinal Features of Down Syndrome.2 Hall noted that 6 of these features were present in 90% of Down newborns, and all affected newborns had at least 4 of these features:



1) hypotonia           4) excess posterior neck skin  7) anomalous auricles

2) poor moro reflex    5) flat facial profile         8) pelvic dysplasia

3) hyperextensibility  6) slanted palpebral fissures  9) single palmer crease  

   of joints    

10) 5th finger anomaly

Other common head and neck findings include epicanthic folds, Brushfield spots, small and open mouth, protruding tongue, narrow palate, short and broad neck.

Airway and hearing problems are common in Down patients.

Airway:

Sleep apnea occurs in up to 50% of Down patients.4 Anatomic, functional, and central mechanisms may all contribute to airway obstruction in these patients. Micrognathia, narrow palate, and midface hypoplasia may impinge both the naso- and oro-pharyngeal airway. Hypopharyngeal collapse during inspiration has been observed in Down patients. An abnormal hypoxic stimulus for respiration may be a contributing factor in some cases.

Central vs. obstructive apnea can be differentiated by the lack of respiratory effort in central apnea. Patients with obstructive sleep apnea may benefit from UPPP. Adenotonsillectomy is indicated in these patients if adenotonsillar hypertrophy exists. Control of upper airway infections is an essential part of sleep apnea treatment.

Hearing:

The incidence of hearing loss in Down syndrome patients is 42-78%.4 Conductive hearing loss due to middle ear effusion is most common. Sensorineural hearing loss is rare in affected children but common in older patients(due to age, repeated infections, and perhaps the observed bony deposition along the basal spiral tract.4

Anatomic anomalies in Down patients that contribute to chronic middle ear effusion and conductive hearing loss include external auditory canal stenosis(precludes TM inspection) and eustachian tube cartilage anomalies(promotes stasis and ascending infection). Functional factors include hypotonicity of the tensor veli palatini (poor eustachian tube opening). Altered T-cell function in these patients may promote otitis media.4

Myringotomy and tube placement, along with antibiotic therapy, is the treatment of choice for Down patients with middle ear effusion. Those with persistent hearing loss often improve with conductive hearing aids. Ideally, all patients with Down syndrome should undergo otologic and audiologic examination prior to 18 months of age. Several studies have shown that hearing improvement in Down patients improves language development and social function.

Occult Findings:

Cervical manipulation should be minimized in Down patients, since 16% have odontoid abnormalities, and 15% have atlantoaxial instability.2

CHARGE Association

The anomalies that comprise CHARGE association are: Coloboma (uni- or bilateral coloboma of iris, retina, and/or disc in 50%) Heart defects(PDA, VSD, ASD, cushion defect, aortic coarctation, tetrology in 50%) Atretic choanae(65%) Retarded postnatal growth(50%) and CNS defects(mild mental retardation in 50%) Genital hypoplasia in males(50%) Ear anomalies( low set/lop/cup-shape/etc. in 50%) and deafness

CHARGE is thought to arise from a defect in the development or maturation of cephalic neural crest cells. Polyhydramnios occurs with CHARGE in about 50% of cases. One-third of affected infants die in the 1st 3 months. The mortality rate is even higher in those with both cardiac defects and choanal atresia.2

Characteristic facies include square face with malar flattening, pinched nostrils, long philtrum, prominent columella, high nasal bridge, small mouth and cleft palate. Each of these facial anomalies, as well as swallowing difficulty and unilateral facial palsy occur in about 50% of affected patients.

Patients with CHARGE associations may have both airway and hearing problems.

Airway:

Complete nasal obstruction is common in affected patients, since choanal atresia is bilateral in 65% of cases. If unilateral, it occurs more often on the left. Infants with bilateral choanal atresia may exhibit paradoxic cyanosis. Treatment consists of securing an oral airway until the infant learns to mouth breathe at 2-3 months of age.2

Hearing:

The hearing loss typical of CHARGE patients is a mixed progressively worsening hearing loss, with a wedged shaped audiogram. Histologically, a Mondini defect is often found in the pars inferioris, with complete absence of the pars superioris.2

Treacher Collins Syndrome (Mandibulofacial dysostosis, Franceschitti-Zwahlen-Klein):

Treacher Collins Syndrome involves anomalous derivatives of the 1st and 2nd pharyngeal arch, groove, and pouch. It is inherited as autosomal dominant with variable expressivity. New mutations are responsible for about 60% of cases, and are more common with older fathers. Intelligence is usually normal.2

Treacher Collins facies are characteristic. The palpebral fissures are short, and slope laterally downward. The lower eyelid often has no cilia medially, and a coloboma is present laterally. The supraorbital rims and zygomas are hypoplastic, giving the false impression of a large nose. The large mouth is down-turned, and the chin is receded. The auricles are malformed, often with meatal atresia. Microtia occurs in 60% of patients.

Radiography shows severely underdeveloped malar bones with nonfusion of the zygomatic arches. Mandible films show a small, retrognathic mandible with antegonial notching and an open bite.

Treacher Collins syndrome patients may have problems with airway maintenance and hearing.

Airway

The hypoplastic, retrognathic mandible of these patients may lead to airway difficulty, especially if the need for intubation or laryngoscopy arises. The intubation procedure described above for the hypoplastic mandible is helpful in these patients. In older childhood, these patients may develop obstructive sleep patterns, which may respond to tonsillectomy or mandibular osteotomy procedures.

Hearing:

Treacher Collins patients often have conductive hearing loss, which may be congenital or acquired. Congenital causes of hearing loss include meatal or canal atresia, ossicle defects, or middle ear obliteration with connective tissue. The inner ears are usually normal. Acquired hearing loss is due to eustachian tube dysfunction, probably caused by palatopharyngeal incompetence (70% of Treacher Collins have cleft palate or related problem). 2

Crouzon Syndrome (Craniofacial Dysostosis):

Crouzon syndrome was first described by Crouzon in 1912. It is inherited as autosomal dominant, with about 50% of cases representing new mutations. It occurs with a frequency of about 1 in 25,000. Intelligence is normal. Facies are characteristic, and must include ocular proptosis (due to shallow orbits).2 Other common features are craniosynostosis (usually brachycephaly), maxillary hypoplasia, crossbite with crowding of maxillary teeth and lateral palatal swellings.

These patients often have problems with airway and hearing.

Airway:

Airway problems in these patients are primarily due to the hypoplastic midface, which results in a decreased nasopharyngeal space. Infants with Crouzon syndrome may exhibit paradoxical cyanosis, whereby cyanosis is only relieved with crying (and therefore oral breathing). Treatment involves securing an oral airway until the patient is 2-3 months of age, when oral breathing is learned. During later childhood, these patients may develop obstructive sleep patterns, which may respond to adenotonsillectomy.

Hearing:

Although external canal atresia is seen in about 13% of these patients, conductive hearing loss occurs in over 50%. 2 Hearing loss in these patients is usually acquired, from eustachian tube dysfunction. In these patients, eustachian tube dysfunction is thought to occur because of midface hypoplasia, and the resulting decreased nasopharyngeal space. These patients often require multiple sets of middle ear ventilation tubes.

Occult Findings:

Cervical manipulation should be limited during intubation in these patients, since about 30% have cervical spine anomalies (mostly vertebral fusions/ C2-3 73%).2

BIBLIOGRAPHY

1) Crysdale W.S., and Gaffney R.J.,: Malformations and Syndromes. In: Pediatric Otolaryngology, Volume I, 3rd edition. C.D. Bluestone, S.E. Stool, and Kenna(Eds.). W.B. Saunders, Philadelphia, pp. 51-70, 1995.

2) Strome M.: Down's syndrome: A modern Otorhinolaryngological perspective. Laryngoscope, 91: 1581-1594, 1981.

3) Handler S.D., and Keon T.P,: Difficult laryngoscopy/intubation: The child with mandibular hypoplasia. Ann Otol Rhinol Laryngol, 92: 401-404, 1983.

4) Strome S.E., and Strome M.: Down syndrome: An otolaryngologic perspective. J Otolaryngol 21: 394-397, 1993.

5) Gorlin R.J., Cohen Jr., M.M., and Levin L.S.: Syndromes of the Head and Neck, 3rd Edition. Oxford University Press, Oxford, pp. 33-40,524-526, 649-652,700-705,881-882. \