You are in: eMedicine Specialties > Otolaryngology and Facial Plastic Surgery > CRANIOFACIAL SURGERY Pierre Robin SyndromeArticle Last Updated: May 19, 2006AUTHOR AND EDITOR INFORMATIONSection 1 of 9
  Author: Ted L Tewfik, MD, FRCS(C), Professor, Department of Otolaryngology, Director of Continuing Medical Education of Otolaryngology, McGill University Medical School; Director, Director of Professional Affairs of Otolaryngology, Department of Otolaryngology, Montreal Children's Hospital; Senior Staff, Montreal General Hospital and Royal Victoria Hospital Ted L Tewfik is a member of the following medical societies: American Academy of Otolaryngology-Head and Neck Surgery, American College of Surgeons, American Society of Pediatric Otolaryngology, Canadian Medical Association, Canadian Society of Otolaryngology-Head & Neck Surgery, Quebec Medical Association, and Royal College of Physicians and Surgeons of Canada Coauthor(s): Nathalie Trinh, MD, Consulting Staff, Department of Otolaryngology, Jean Talon Hospital, Canada; Ahmad S Teebi, MD, Head, Section of Clinical Genetics and Dysmorphology, Division of Clinical and Metabolic Genetics, The Hospital for Sick Children; Professor, Departments of Pediatrics, Medical Genetics, and Microbiology, University of Toronto Editors: Ari J Goldsmith, MD, Program Director, Associate Professor, Department of Otolaryngology, Division of Pediatric Otolaryngology, State University of New York Downstate Medical Center; Francisco Talavera, PharmD, PhD, Senior Pharmacy Editor, eMedicine; David W Stepnick, MD, Associate Professor, Departments of Plastic Surgery and Otolaryngology-Head and Neck Surgery, Case Western Reserve University School of Medicine; Vice President, University Otolaryngology-Head and Neck Surgery, Inc; Christopher L Slack, MD, Otolaryngology-Facial Plastic Surgery, Private Practice, Associated Coastal ENT; Medical Director, Treasure Coast Sleep Disorders; Arlen D Meyers, MD, MBA, Professor, Department of Otolaryngology-Head and Neck Surgery, University of Colorado School of Medicine Author and Editor Disclosure Synonyms and related keywords: Pierre Robin syndrome, Pierre Robin sequence, Robin syndrome, Robin sequence, micrognathia, cleft palate, bifid uvula, double uvula, submucous cleft, retroglossoptosis, mandibular hypoplasia, glossoptosis, macroglossia, ankyloglossia, obstructive sleep apnea, OSA, otitis media, hearing loss, auricular anomalies, velopharyngeal insufficiency, speech defects, hypermetropia, myopia, astigmatism, corneal sclerosis, nasolacrimal duct stenosis, heart murmurs, pulmonary stenosis, patent ductus arteriosus, patent foramen ovale, atrial septal defect, pulmonary hypertension, syndactyly, dysplastic phalanges, polydactyly, clinodactyly, hyperextensible joints, oligodactyly, clubfeet, metatarsus adductus, femoral malformations, coxa varus or valgus, short femur, flexure contractures, congenital hip dislocation, genu valgus, synchondrosis, tibial abnormalities, scoliosis, kyphosis, lordosis, vertebral dysplasia, sacral agenesis, coccygeal sinus, language delay, epilepsy, neurodevelopmental delay,hypotonia,hydrocephalus,undescended testes, hydronephrosis, hydrocele, Stickler syndrome, trisomy 11q syndrome, trisomy 18 syndrome, velocardiofacial syndrome, Shprintzen syndrome, deletion 4q syndrome, rheumatoid arthropathy, hypochondroplasia, Möbius syndrome, CHARGE association BACKGROUNDSection 2 of 9
  Lannelongue and Menard first described Pierre Robin syndrome in 1891 in a report on 2 patients with micrognathia, cleft palate, and retroglossoptosis. In 1926, Pierre Robin published the case of an infant with the complete syndrome. Until 1974, the triad was known as Pierre Robin syndrome; however, the term syndrome is now reserved for those errors of morphogenesis with the simultaneous presence of multiple anomalies caused by a single etiology. The term sequence has been introduced to include any condition that includes a series of anomalies caused by a cascade of events initiated by a single malformation. ETIOLOGY AND PATHOGENESISSection 3 of 9
Frequency This heterogeneous birth defect has a prevalence of approximately 1 per 8500 live births. The male-to-female ratio is 1:1, except in the X-linked form. Etiology Autosomal recessive inheritance is possible. An X-linked variant has been reported involving cardiac malformations and clubfeet. Pathogenesis Three pathophysiological theories exist to explain the occurrence of Pierre Robin sequence.
OTOLARYNGOLOGIC MANIFESTATIONSSection 4 of 9
Micrognathia is reported in the majority of cases (91.7%). It is characterized by retraction of the inferior dental arch 10-12 mm behind the superior arch. The mandible has a small body, obtuse genial angle, and a posteriorly located condyle. The growth of the mandible catches up during the first year; however, mandibular hypoplasia resolves and the child attains a normal profile by approximately age 5-6 years. The jaw index is defined as the alveolar overjet multiplied by the maxillary arch divided by the mandibular arch. This index can be used to objectify mandibular growth. The alveolar overjet is the distance between the most anterior points of the upper and lower alveolar arches. The maxillary arch is the measurement between the 2 tragi via the subnasal point, and the mandibular arch is the distance from the right to the left tragus passing through the pogonion. Glossoptosis is noted in 70-85% of reported cases. Macroglossia and ankyloglossia are relatively rare findings, noted in 10-15% of reported cases. The combination of micrognathia and glossoptosis may cause severe respiratory and feeding difficulty in the newborn. Obstructive sleep apnea may also occur. In reported series, the prevalence of cleft palate varies from 14-91%. It can affect the soft and hard palate and is usually U-shaped (80%) or V-shaped. Occasionally, it may present as a bifid or double uvula or as an occult submucous cleft. The most common otic anomaly is otitis media, occurring 80% of the time, followed by auricular anomalies in 75% of cases. Hearing loss, mostly conductive, occurs in 60% of patients, while external auditory canal atresia occurs in only 5% of patients. Temporal bone computerized planigraphs demonstrate inadequate pneumatization of the mastoid cavities in many patients with Pierre Robin sequence. Gruen et al.(2005) studied 13 temporal bones by light microscopy and identified multiple architectural anomalies involving the entire ear, including abnormal auricles, and anomalies of the ossicles, including abnormal stapes footplates. All specimens showed signs of middle ear infection. Anomalies of the inner ear included aplasia of the lateral semicircular canals, a large vestibular aqueduct, and unusually large otoconia. In the mastoid process there were islands of cartilage in the expected position of Reichert's cartilage and dehiscence of the fallopian canal. Loss of cochlear hair cells was seen in children whohad antemortem hypoxia Nasal deformities are infrequent and consist mostly of anomalies of the nasal root. Dental and philtral malformations occur in one third of cases. Laryngomalacia occurs in approximately 10-15% of patients with Pierre Robin sequence. Gastroesophageal reflux and esophagitis has also been described. Speech defects occur frequently in patients with Pierre Robin sequence. Velopharyngeal insufficiency is usually more pronounced in these patients than in those with isolated cleft palate. SYSTEMIC MANIFESTATIONSSection 5 of 9
In general, systemic anomalies are documented in 10-85% of reported cases. Ocular anomalies are reported in 10-30% of patients. The higher frequency is usually observed when an ophthalmologist is consulted. The following lesions occur in decreasing order of frequency: hypermetropia, myopia, astigmatism, corneal sclerosis, and nasolacrimal duct stenosis. Cardiovascular findings such as benign murmurs, pulmonary stenosis, patent ductus arteriosus, patent foramen ovale, atrial septal defect, and pulmonary hypertension have all been documented. Their prevalence varies in the literature from 5-58%. Anomalies involving the musculoskeletal system are the most frequent systemic anomalies (noted in 70-80% of cases). They include syndactyly, dysplastic phalanges, polydactyly, clinodactyly, hyperextensible joints, and oligodactyly in the upper limbs. In the lower extremities, foot anomalies (clubfeet, metatarsus adductus), femoral malformations (coxa varus or valgus, short femur), hip anomalies (flexure contractures, congenital dislocation), anomalies of the knee (genu valgus, synchondrosis), and tibial abnormalities have been reported. Vertebral column deformities include scoliosis, kyphosis, lordosis, vertebral dysplasia, sacral agenesis, and coccygeal sinus. Central nervous system (CNS) defects such as language delay, epilepsy, neurodevelopmental delay, hypotonia, and hydrocephalus may occur. The incidence of CNS defects is around 50%. Genitourinary defects may include undescended testes (25%), hydronephrosis (15%), and hydrocele (10%). Associated syndromes and conditions include Stickler syndrome, trisomy 11q syndrome, trisomy 18 syndrome, velocardiofacial (Shprintzen) syndrome, deletion 4q syndrome, rheumatoid arthropathy, hypochondroplasia, Möbius syndrome, and CHARGE association. CONSERVATIVE MANAGEMENTSection 6 of 9
Children with severe micrognathia may have significant respiratory obstruction at birth, requiring a nasopharyngeal airway or intubation. Because of micrognathia, intubation can be very difficult and should be performed by someone experienced with the problematic pediatric airway. For most newborns, the earliest physical problem involves feeding. The cleft hampers the generation of enough negative pressure to nurse. The milk or formula has to be delivered through a bottle with a nipple that has a large hole cut into the top to make the delivery effortless. The nurse plays an extremely important role in teaching the mother the proper feeding technique. A multidisciplinary approach is required to manage the complex features involved in the care of these children and their families. The cleft palate team includes pediatricians, otolaryngologists, plastic surgeons, pedodontists, orthodontists, nurses, speech therapists, audiologists, and social workers. This composition ensures that each patient and family receives the most comprehensive care plan, using all available resources from birth to adolescence. Fetal sonographic identification of glossoptosis with micrognathia is possible in early and mid pregnancy and suggests the possibility of Pierre Robin sequence. SURGICAL MANAGEMENTSection 7 of 9
Treatment is prioritized according to the severity of airway compromise followed by the extent of feeding difficulties. Infants with pronounced micrognathia may experience severe respiratory distress or failure to thrive. Surgical intervention is necessary in these cases. While many different surgical procedures have been described, tracheostomy remains the most widely used technique. Other surgical procedures, such as subperiosteal release of the floor of the mouth (see Image 6), and different types of glossopexy, such as the Routledge procedure or other forms of tongue-lip adhesions, can be used. Any glossopexy should be released before significant dentition develops (age 9-12 mo). Mandibular lengthening by gradual distraction may be used for severe mandibular hypoplasia that causes obstructive apnea. As the therapy of choice to correct the conductive hearing loss and prevent middle ear complications, tympanostomy tubes are usually inserted when the palatoplasty is performed. Surgical procedures to repair the cleft palate, details of which are not included herein, fall into 1 of 2 categories. The first category comprises all the one-stage procedures, and the second includes all multistage approaches in which the velum is initially closed and hard palate repair is delayed. The most common procedure is the single-stage palate (hard and soft) closure, performed when the child is aged 6-18 months. MULTIMEDIASection 8 of 9
REFERENCESSection 9 of 9
Article Last Updated: May 19, 2006 | |||||||||||||||||||||||||||||||||||||||||||||||
