An oral synechia is an adhesion between the maxilla and the mandible; these adhesions can be found at various locations in the oral cavity. The presence of oral synechiae associated with cleft palate represents a rare congenital deformity. Oral synechiae with cleft palate can have serious implications for airway management and feeding in babies, and hence requires early intervention to reduce morbidity. Two cases of congenital oral synechiae accompanied by cleft palate, in which the synechiae veiled the oral cavity restricting a detailed intraoral examination, are reported here.
An oral synechia is a fibrous or soft tissue adhesion between the maxilla and the mandible; these adhesions can be present at various locations in the oral cavity. Oral synechia is a rare congenital deformity with very few documented cases in the literature. It may coexist with other craniofacial anomalies and is most frequently associated with cleft palate. Respiratory distress, feeding difficulty, and restricted mouth opening are the common presenting signs of an oral synechia, often requiring prompt intervention. Two cases of congenital oral synechiae accompanied by cleft palate are reported here.
A referral call was attended in the neonatal intensive care unit for a 1-day-old female infant, born preterm at 32 weeks of gestation with a low birth weight of 1.3 kg, as the third child to a 23-year-old, gravida 3, para 1, abortus 1 mother. A prenatal ultrasound performed at 29 weeks of gestation had revealed severe oligohydramnios. There was no prenatal history of maternal infection, gestational diabetes, or exposure to alcohol, tobacco, medications, or toxins. The baby was born out of a non-consanguineous marriage. The family history did not reveal any synechiae, orofacial clefts, joint pterygia, or contractures. The Apgar scores of the baby at 1, 5, and 10 min were 4, 6, and 7, respectively. She had developed periods of respiratory distress and was receiving oxygen via a hood at the time of presentation.
On examination, the baby had restricted mouth opening due to the presence of a soft membranous adhesion between the palate and the floor of the mouth. The membrane appeared to be running from the palate to the ventrolateral aspect of the tongue on both sides, with a small slit in the middle of the membrane. The diagnosis of oral synechia was made ( Fig. 1 ). A cleft of the secondary palate was suspected. However, further detailed examination of the oral cavity was not possible as the synechia veiled the oral cavity. Oral feeding was not possible, thus nasogastric tube feeding was commenced. There were no obvious deformities in relation to the ears, nose, digits, extremities, and genitalia. Echocardiography revealed an atrial septal defect and patent ductus arteriosus, and the baby was placed under regular cardiac evaluation.
On the third postnatal day, a surgical transection of the synechiae was done under monitored anaesthetic care with oxygen inhalation via nasal prongs. The membranes were divided from the palatal aspect with the aid of surgical diathermy. The procedure was well tolerated by the patient.
Desaturation did not occur during the intervention and the surgery was uneventful. Mouth opening improved and a detailed examination of the oral cavity was made. A secondary cleft of the palate was confirmed. Oral feeding was started on day 2 postoperative and the baby was discharged on day 4 postoperative. During follow-up, the baby was assessed to be growing well and was under regular cardiac evaluation. The surgical repair of the cleft palate was planned at a later date.
An 8-day-old female infant, weighing 3 kg, was brought to the maxillofacial clinic as the parents were having difficulty feeding her. She had been born at a remote health centre. The parents reported that there had been no complications during the pregnancy. The baby was the first child to these non-consanguineous parents. The maternal history did not reveal any significant findings. The family history was also unremarkable.
Examination revealed reduced mouth opening. Intraorally, two fibrous bands suggestive of synechiae were seen, each running from the ventrolateral surface of the tongue to the palate. Cleft of the palate could be visualized through the gap between the two bands, as the bands were cord-like in nature ( Fig. 2 ). Temporomandibular joint movement was within the restricted range allowed by the synechiae. No abnormalities were detected regarding the digits, nose, ears, and genitalia. Echocardiography revealed no abnormalities.
A surgical transection was performed under sedation on the tenth postnatal day. Mouth opening improved. Feeding was encouraged. Repair of the cleft of the secondary palate was planned at a later date.
Oral synechia accompanied by cleft palate was first described by Fuhrmann et al. as cleft palate lateral synechia syndrome. Both patients reported here presented a cleft of the secondary palate associated with the synechiae. A similar case of a baby with cleft palate lateral synechia syndrome has been reported at the authors’ institute. Furthermore, oral synechia may be a component of many syndromes, such as Van der Woude syndrome, popliteal pterygium syndrome, Fryns syndrome, cleft palate lateral synechia syndrome, and oral-facial-digital syndrome.
Despite many theories, the aetiopathogenesis of oral synechiae remains unclear. The persistence of the buccopharyngeal membrane (presence of a remnant) and an abnormality occurring during the formation of the subglossopalatal membrane are the main theories put forth to explain the aetiopathogenesis of synechia. During embryological development of the palate, the persisting buccopharyngeal membrane hinders the inferior and forward motion of the tongue. The tongue is positioned between the palatal shelves superiorly and posteriorly and thus prevents fusion of the palatal shelves in the midline resulting in the cleft of the palate. This may explain the association of oral synechiae with the cleft palate anomaly. In the cases presented herein it was observed that the synechiae were extending from the free margins of the cleft palate to the ventrolateral aspect of the tongue. The tongue was between the cleft in the soft palate posterosuperiorly when the synechiae were detached. So the cleft palate may have been the result of the synechiae. Similarly, Goodacre and Wallace emphasized that the interposition of the tongue between the palatal shelves caused cleft palate and that the prolonged close contact between the floor of the mouth and the palate was the cause of oral synechiae. Other aetiologies of intraoral synechiae reported in the literature are heredity, long-standing contact of the gingival epithelium between the palate and the floor of the mouth, local ischaemia of amniotic bands causing pressure on the first branchial arch, disturbance in the interaction of growth factors, and the intake of meclizine or high-dose vitamin A.
The problems occurring as a result of oral synechiae include restricted mouth opening, feeding difficulty, and their consequences, as well as respiratory distress. Resection of the bands at the earliest opportunity is recommended to secure a definitive airway, provide nutritional support to prevent growth abnormalities, and allow early mobilization of the jaws to prevent ankylosis. However, there are cases reported in the literature in which surgery has been delayed to allow the baby to gain weight and become fit for surgery under anaesthesia. There have also been cases of spontaneous resolution of the membrane. Thus the timing of surgery remains controversial due to the lack of adequate data owing to the rarity of the disease. However, it is believed that the decision on when to intervene will depend on the problems and the co-morbidities associated with each individual case.
Surgery for oral synechiae involves transection of the bands. The bands or membrane, if fibro-muscular in nature, can also be used as additional tissues to repair the palatal cleft at a later date. However, the synechiae in the cases presented herein were thin membranous tissues. Detachment of the synechiae was done from the palatal aspect and the tissues were left in situ to atrophy. It was opted to divide from the palatal aspect, as division from the floor of the mouth or the ventral surface of the tongue would carry a greater risk of bleeding.
Achieving anaesthesia is a challenge in cases of synechiae, as oral intubation is not possible. Nasotracheal intubation with a flexible fibre-optic bronchoscope of a size appropriate for infants may not be readily available in every health centre. An alternative would be to provide inhalation anaesthesia with the provision of an emergency surgical airway just in case the airway is compromised, as was done in the cases presented here.Oral synechia with cleft palate is a rare congenital finding that can have serious implications for airway management and feeding, and may lead to subsequent growth abnormalities.