Craniofacial conditions
Congenital, mostly symmetric underdevelopment of the cheekbone, lower jaw and ears – with normal intellectual development.
Treacher Collins syndrome (mandibulofacial dysostosis) is a congenital malformation of the facial bones. Typical features are a mostly symmetric underdevelopment of the cheekbone and lower jaw, downward-and-outward slanting eyelid axes, notches of the lower eyelids (colobomas) as well as ear malformations with conductive hearing loss. It is not a craniosynostosis – the brain and intellectual development are usually normal. In the foreground are the airway, hearing and the step-by-step reconstruction of the face.
The most common cause are changes in the TCOF1 gene, which encodes the protein "treacle"; more rarely the genes POLR1C and POLR1D are affected.[1] These changes disturb the early development of the so-called neural crest cells, from which a large part of the facial bones arises.[2] Inheritance is mostly autosomal dominant (autosomal recessive for POLR1C); about 60 % of cases arise de novo. The frequency is estimated at about 1 : 50,000.
Intellectual development is normal. The expression ranges from very mild to severe.
Because of the small, recessed lower jaw and narrow airways, breathing problems can occur – similar to Pierre Robin sequence. In severe cases, positioning, breathing aids, a mandibular distraction or, rarely, a temporary tracheotomy (tracheostoma) are necessary. Early assessment at a specialised centre is decisive.
Due to middle-ear and ear-canal malformations, there is usually a bilateral conductive hearing loss. As the inner ear generally works, early provision of a bone-conduction hearing system (e.g. bone-conduction hearing aid / BAHA) is very effective and supports language development. Speech therapy and regular hearing tests are important.
Treatment is carried out in several carefully planned steps:
The order depends on function (breathing, hearing, eyes) and growth. Definitive procedures are often only completed in adolescence or early adulthood.
The work-up includes: clinical examination by a craniofacial team, hearing test and ENT assessment, sleep / airway diagnostics if needed, 3D imaging of the facial bones as well as genetic testing (TCOF1, POLR1C, POLR1D).
Ideal is care by a team with oral and maxillofacial / craniofacial surgery, ENT and audiology, paediatrics, anaesthesia, ophthalmology, orthodontics and paediatric dentistry, speech therapy, genetics as well as psychology and social counselling.
The prognosis is favourable: intellectual development is normal and, after securing the airway in the newborn period, life expectancy is also normal. The severity is however very variable – from very mild to marked. With early hearing provision and staged reconstruction, most affected people achieve good function and quality of life. Decisive are the timely securing of airway and hearing as well as long-term, coordinated support.
Airway and hearing are early priorities; reconstruction over years.
Airway takes priority (positioning, mandibular distraction or tracheostomy if needed); early hearing assessment; feeding.
Bone-conduction hearing aid (initially on a softband) for speech development; mandibular distraction if needed.
Correction of eyelid coloboma to protect the cornea; cleft palate closure if present.
Bone reconstruction of cheekbone and eye socket; external ear reconstruction (rib cartilage or implant).
Osteotomy after sufficient growth, depending on the jaw joint.
Fat transfer/contouring, rhinoplasty; ear canal surgery selectively.
Hearing, vision, breathing/sleep, psychosocial aspects.
Typical course – highly individual. Timing, order and type of procedures are always determined individually at the specialised centre and may differ markedly. This is based on established craniofacial treatment concepts (incl. ERN CRANIO). See also Treatment pathways and Craniofacial library.
Further pages on this condition – diagnostics, treatment, cross-cutting topics and research.
Selected authoritative external sources on this condition.
External third-party sites; linked, not hosted. Not a recommendation in individual cases; does not replace medical advice.