Resident Professor and Head Assistant Professor Intern Dept. of Pediatrics Padmashree Dr Vithalrao Vikhe Patil Medical College and Hospital Ahmednagar Gujarat Address for correspondence Dr Sunil Mhaske Professor and Head Dept. of Pediatrics Padmashree Dr Vithalrao Vikhe Patil Medical College and Hospital Near Govt. Milk Dairy Vilad Ghat Ahmednagar 414 111 Gujarat ABSTRACT Pierre Robin syndrome or sequence is a condition present at birth in which the infant has a smaller than normal lower jaw a tongue that falls back in the throat and has difficulty in breathing. Most infants but not all will also have a cleft palate but none will have a cleft lip. This heterogeneous birth defect has prevalence of approximately 1 per 8 500 live births. The male to female ratio is 1 1 except in the X linked form. Autosomal recessive inheritance is possible. Keywords Cleft soft palate micrognathia obstructive sleep apnea otitis media Pierre Robin sequence or complex is the name given to a birth condition that involves the lower jaw which is either small in size micrognathia or set back from the upper jaw retrognathia . As a result the tongue tends to be displaced back towards the throat where it can fall back and obstruct the airway glossoptosis . Most infants but not all will also have a cleft palate but none will have a cleft lip. CASE REPORT A 6 month old female child was brought to our outpatient department OPD by mother with complaints of fever cough and running nose since last 2 days. Fever was of gradual onset slowly rising intermittent moderate grade without any chills or rigors. Cough was also of gradual onset dry intermittent without any diurnal or postural variations. Parents gave history of repeated attacks of upper respiratory tract infections associated with a single episode of otitis media in the past. Also parents gave history of disturbed sleep pattern of baby. She was fifth issue of nonconsanguineous marriage born as a full term normal hospital delivery with good cry and weight at birth. The other siblings includes two males and two females were not having any congenital anomaly. On examination her weight was 5.27 kg length 61 cm head circumference 39 cm normal 44 cm and chest circumference 38 cm. All vital parameters were within normal limits as per her age. On head to toe examination she was having high arched U shaped cleft soft palate. Jaw was very small with small receding chin Figs. 1 and 2 . Also jaw was far back in throat and the tongue was large compared to the jaw. There was a small opening in the roof of mouth that caused choking. She was having congenital talipes equino varus CTEV of right foot. Presently there was no earache or ear discharge. The systemic examination was not showing any abnormality. An opinion from ENT specialist was also taken to examine middle and inner ear which stated no active otitis media as well as any hearing loss. DISCUSSION Lannelongue and Menard first described Pierre Robin syndrome in 1891 in a report on 2 patients with micrognathia cleft palate and retro glossoptosis. 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. Over the years there have been several names given to the condition including Pierre Robin syndrome Pierre Robin triad. Based on the varying features and causes of the condition either Robin sequence or Robin complex may be an appropriate description for a specific patient. Pierre Robin was a French physician who first reported the combination of small lower jaw cleft palate and tongue displacement in 1923. This heterogeneous birth defect has prevalence of approximately 1 per 8 500 live births. The male to female ratio is 1 1 except in the X linked form. Autosomal recessive inheritance is possible. An X linked variant has been reported involving cardiac malformations and clubfeet. Otolaryngologic Manifestations Micrognathia is reported in the majority of cases 91.7 Figs. 3 and 4 . 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. The combination of micrognathia and glossoptosis may cause severe respiratory and feeding difficulty in the newborn. Obstructive sleep apnea may also occur. It can affect the soft and hard palate and is usually U shaped or V shaped Fig. 5 . Occasionally it may present as a bifid or double uvula or as an occult submucous cleft. The most common otic anomaly is otitis media followed by auricular anomalies. Hearing loss is mostly conductive 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. 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 Manifestations In general systemic anomalies can be seen in various cases. Anomalies involving the musculoskeletal system are the most frequent systemic anomalies. 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. Cardiovascular findings such as benign murmurs pulmonary stenosis patent ductus arteriosus patent foramen ovale atrial septal defect and pulmonary hypertension have all been documented. Central nervous system CNS defects such as language delay epilepsy neurodevelopmental delay hypotonia and hydrocephalus may occur. Ocular anomalies are seen as per following in decreasing order of frequency hypermetropia myopia astigmatism corneal sclerosis and nasolacrimal duct stenosis. Genitourinary defects may include undescended testes hydronephrosis and hydrocele. Associated syndromes and conditions include Stickler syndrome trisomy 11q syndrome trisomy 18 syndrome velocardiofacial Shprintzen syndrome deletion 4q syndrome rheumatoid arthropathy hypochondroplasia Moebius syndrome and CHARGE association. Pathogenesis Three pathophysiological theories exist to explain the occurrence of Pierre Robin sequence. The mechanical theory This theory is the most accepted. The initial event mandibular hypoplasia occurs between the 7th and 11th week of gestation. This keeps the tongue high in the oral cavity causing a cleft in the palate by preventing the closure of the palatal shelves. This theory explains the classic inverted U shaped cleft and the absence of an associated cleft lip. Oligohydramnios could play a role in the etiology since the lack of amniotic fluid could cause deformation of the chin and subsequent impaction of the tongue between the palatal shelves. The neurological maturation theory A delay in neurological maturation has been noted on electromyography of the tongue musculature the pharyngeal pillars and the palate as has a delay in hypoglossal nerve conduction. The spontaneous correction of the majority of cases with age supports this theory. The rhombencephalic dysneurulation theory In this theory the motor and regulatory organization of the rhombencephalus is related to a major problem of ontogenesis. Conservative Management In the majority of patients conservative management with close observation and follow up is successful. The natural history shows that with normal growth airway compromise resolves without immediate surgical intervention. Isolated Pierre Robin syndrome patients usually respond more favorably to the conservative approach. Recently Abel et al 2012 reported on long term outcomes in 104 children with Pierre Robin syndrome and airway obstruction. In most children 86.5 airway obstruction was managed by conservative measures or with a nasopharyngeal airway NPA for a few months. Prone positional therapy has proved to be highly efficient in airway management. Oral airway placement laryngeal mask nasopharyngeal stenting and short term intubation 2 week are other options in case positioning is inadequate. Intubation is often difficult owing to the micrognathia and should be performed by someone specialized in problematic pediatric airway management. Feeding difficulties can be alleviated by upright feeding techniques modification of the nipple for bottle feeding temporary use of nasogastric or orogastric feeding tube and the placement of a gastrostomy. Palatal plates such as the pre epiglottic baton plate which have a velar extension pull the base of the tongue forward. This can be helpful in the relief of airway obstruction and it also facilitates the swallowing mechanism during feeds. Surgical Management Infants with pronounced micrognathia may experience severe respiratory distress or failure to thrive. Treatment is prioritized according to the severity of airway compromise followed by the extent of feeding difficulties. Lidsky et al 2008 reviewed 67 Pierre Robin syndrome patients from their multidisciplinary cleft team at a tertiary pediatric hospital. They found that delaying airway intervention may necessitate feeding assistance via a G tube. Surgical intervention is necessary in these cases. Although 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 Fig. 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 months . Mandibular lengthening by gradual distraction may be used for severe mandibular hypoplasia that causes obstructive apnea. Published articles by Hong and others 2011 2012 on the use of mandibular distraction osteogenesis in Pierre Robin syndrome patients have described significant improvements in both airway obstructive symptoms and feeding abnormalities. Patients showed clinical and objective improvements in reflux and swallowing function after surgery. 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. BIBLIOGRAPHY 1. Abel F Bajaj Y Wyatt M Wallis C. The successful use of the nasopharyngeal airway in Pierre Robin sequence an 11 year experience. Arch Dis Child. 2012 97 4 331 4. 2. Bath AP Bull PD. Management of upper airway obstruction in Pierre Robin sequence. J Laryngol Otol. 1997 111 12 1155 7. 3. Breugem CC Courtemanche DJ. Robin sequence clearing nosologic confusion. Cleft Palate Craniofac J. 2010 47 2 197 200. 4. Bronshtein M Blazer S Zalel Y Zimmer EZ. Ultrasonographic diagnosis of glossoptosis in fetuses with Pierre Robin sequence in early and mid pregnancy. Am J Obstet Gynecol. 2005 193 4 1561 4. 5. B tow KW Hoogendijk CF Zwahlen RA. 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