Treacher Collins Syndrome or TCS is a rare autosomal dominant congenital disorder. This disorder is recorded in 1 out of 50,000 births. This syndrome is also known as Treacher Collins- Franceschetti Syndrome or also mandibulofacial dysostosis. Craniofacial deformities are common determinants of the syndrome; this means that the condition causes growth and development issues of the head and face. It hinders the development of mandibles, cheek bone or jaw bones,etc. Facial defects and hearing loss are a common difficulty experienced by the TCS affected children. The severity of the condition may range from mild to serious. Though facial deformity is normal under this condition, the intelligence of the child is often not affected.
The condition derives its name after the English surgeon and eye doctor Edward Treacher Collins (1862-1932). Edward Treacher Collins describes the condition’s significant aspects in 1900. In the year 1949 David Klein and Adolphe Franceschetti re-described the condition on their observations and termed it as mandibulofacial dysostosis. The condition is congenital, means it is present at birth. It is either inherited from parents or occurs due to fresh genetic mutation during conception. There is no cure for the condition but craniofacial surgeries can improve look, speech, etc.
Causes of Treacher Collins Syndrome
As mentioned above the mandibulofacial dysostosis is either inherited or developed through mutation of a certain gene. Treacher Collins syndrome happens due to mutation of TCOF1 gene. The gene is present in chromosome 5. It is responsible for development of face-features. In around 50% of all TCS cases the mutation happens during conception spontaneously but what causes this mutation is not yet discovered. In remaining cases the condition occurs when the fetus obtain a faulty gene from either maternal or paternal side. There are around 50 different changes in TCOF1 gene that may lead to the condition. It is not determined how the faulty gene causes deformation of facial features. Hypothetically, the affected gene is said to kill cells of soft tissues, cartilage and facial bone during 3rd to 8th week of fetal development.
Symptoms of Treacher Collins syndrome
Symptoms of Treacher Collins syndrome range from mild (barely noticeable) to extremely severe and disabling. Here are some symptoms that are recorded in case of TCS.
- Cleft palate technically called palatoschisis
- Micrognathia or smaller jaw bone
- Macrostomia or strangely larger mouth
- Smaller zygoma or cheek bone; in some cases cheek bone may be absent
- Pointed and larger nose
- Droopy downwards slanting eye sometimes with notch in the lower eye-lid
- Absence of lower eyelashes
- Overgrowth of hairline beyond scalp and till the cheek
- Ear deformities such as low-set ears, misshaped, proportionately small or absent ears
- Ear canal deformities
- Hearing loss or conductive deafness due to malformed inner ear
Problems faced by the affected child
There are several complications that a Treacher Collins Syndrome affected child has to face. Feeding difficulties is one of the common issues experienced due to cleft palate as it prevents baby from sucking and swallowing. When the size of the tongue is normal but jaw is abnormally smaller, than it may cause obstruction in breathing and may cause other difficulties such as sleep apnea. In such a case a surgical operation called tracheostomy may be needed which is done in severe cases to dilate the wind-pipe.
Cleft palate also leads to speech related issues; it may also result in hearing loss or both. Deafness or improper hearing ability affects the way the child may learn things. Learning difficulties in case of TCS is not due to intelligence issues because in most cases children do not have deprived intellect. Affected children may suffer from dry eye syndrome wherein they do not have sufficient tear to maintain moistness of the eye. This may make the child susceptible to eye infections. Hesitation to socialize may lead to psychological problems such as depression and low self esteem.
There are three highly adopted ways to diagnose Treacher Collins Syndrome. These methods include x-ray, CT scan and MRI. There are also some other techniques which may be suggested by the doctor depending on the case.
Radiograph or X- ray is one of the primary screenings suggested for confirming affliction of mandibulofacial dysostosis. OPG or Orthopantomography is a panoramic x-ray of upper jaw and lower jaw. It provides two-dimensional image from one ear to the other. Another effective technique is to obtain x-ray image of the entire head. Lateral cephalometric radiograph can help in understanding the prevalence of hypoplasia in an affected child. On the other hand the occipitomental radiograph will help determining zygomatic (cheek bone) arch discontinuation.
CT scan or computer tomography scan using thin-slices method proves to be effective in understanding the intensity of atresia and stenosis of middle ear. 2D and 3D CT scan imaging along with VRT and skin and bone surfacing are beneficial in precisely phasing as well as planning for reconstructive surgical operations. Differential diagnosis is used when any other condition is suspected which may be misdiagnosed with Treacher Collins Syndrome.
One of the most famous cases of Treacher Collins Syndrome is of Juliana Wetmore. Juliana is said to have one of the serious cases of TCS. Dr Teng, a skilled neonatal physician, describes her case as the most serious and perhaps the worst TCS case he ever came across. Juliana had no ears at birth which is why bone conduction hearing aid was installed. She also attended speech and language therapy in Miami. She was also thought basic sign language as she cannot speak and is fed through pipe due to malformed mouth.
She had to undergo two major surgeries as well as many operations by the time she was two years old. Despite of several surgeries she lives a danger that holes will occur in her skull. It is said that Juliana may have to undergo surgeries constantly for many years.
Though there is nothing that can be done to reverse the condition or completely cure the affected person, methods can be adopted to improve standard of life of the patient. Depending on the type of condition whether hereditary or mutation of gene, genetic counseling may be required. Dental work, hearing devices, speech therapy and reconstructive surgeries may help in enhancing living of the Treacher Collins Syndrome affected child.