R. J. Palacio’s popular book Wonder, and the subsequent movie release, has placed a spotlight on Treacher Collins syndrome. Treacher Collins syndrome is a rare genetic condition that affects the development of bones and other tissues of the face. Some people show almost unnoticeable signs of the disease, while others have more obvious symptoms. People with Treacher Collins syndrome typically have normal intelligence and a life expectancy consistent with the general population.
Symptoms
According to the National Institutes of Health (NIH)1, about 1 in 50,000 babies are born with Treacher Collins syndrome. While symptoms vary, some noticeable physical characteristics may include:
- Underdeveloped facial bones, especially the cheek bones.
- A smaller than normal jaw and chin, known as micrognathia.
- Cleft palate, or an opening in the roof of the mouth.
- Downward slanting eyes.
- Sparse or absent eyelashes.
- Missing, small, or malformed ears.
- A beak-like nose.
In the most severe cases, underdevelopment of the facial bones can restrict a baby’s airway, resulting in potentially life-threatening respiratory problems. Some people with Treacher Collins syndrome also exhibit other eye deformities that may lead to vision loss. As a result of their physical abnormalities, those with Treacher Collins may have delayed speech or motor development, difficulty eating, and hearing or vision.
Causes
In humans, every cell normally contains 23 pairs of chromosomes, for a total of 46. The first 22 pairs are numbered by size. The other two chromosomes, known as X and Y, are the sex chromosomes that determine if a baby is a boy or a girl.
Chromosomes contain genes that are made up of DNA. Each person has two copies of every gene, one inherited from each parent. Most genes are the same in all people, but less than 1 percent are slightly different. These small differences form each person’s unique physical features.
Treacher Collins syndrome occurs when there is a change in the gene on chromosome 5, which affects facial development. 1 About 40 percent of the time, one parent has the Treacher Collins Syndrome gene.
Diagnosis
If Treacher Collins syndrome is suspected in a child, physicians will assess:
- The airway for evidence of obstruction
- The palate for clefts
- The ability to swallow effectively
- The ears for hearing function
- The eyes for extraocular movement, corneal exposure, and visual acuity
A genetic diagnosis also may be performed that includes:
- A physical examination:
- Distinctive facial features
- Measurements of head circumference, the distance between the eyes, and the length of the arms and legs
- Specialized examinations to view other structures of the body:
- Nervous system (neurological)
- Eyes (ophthalmologic)
- Specialized imaging like x-rays, computerized tomography (CT) scans, or magnetic resonance imaging (MRI)
- Personal medical history including:
- Past health issues of the parents and close family members
- Results of any medical or genetic testing that already has been done
- Laboratory tests:
- Molecular, chromosomal, and biochemical genetic testing
- Tests to measure levels of certain substances in blood and urine
If hearing loss is found within the first six months of life, a craniofacial CT scan can be performed to document the anatomy of the head and neck and the external auditory canal, middle ear, and inner ear. In addition, assessment for dental abnormalities should be made once teeth erupt.
Treatment Options
Treatment for Treacher Collins syndrome usually falls into three age groups:
- Birth to 2 years: airway and feeding difficulties
- 3 years to 12 years: speech therapy and integration into education system
- 13 years to 18 years: orthognathic (jaw) surgery
A child with Treacher Collins syndrome should be treated by a qualified craniofacial medical team. Since the physical abnormalities associated with Treacher Collins can vary significantly, treatment also varies depending on the individual’s needs. Some treatment options may include:
- Surgical improvement of the airway to improve respiratory function.
- Placement of a gastrostomy feeding tube to ensure adequate caloric intake when palate or jaw deformities make eating difficult.
- Bone conduction amplification, speech therapy, and educational intervention for treatment of hearing loss. A hearing aid also may be recommended.
- Craniofacial reconstruction of bones and soft tissue in the face to improve symmetry. This may include:
- Repair of the cleft palate
- Reconstruction of the cheek bones (zygomatic) and eye socket (orbital) once bony development is complete around age 5 to 7
- Jaw (maxillomandibular) reconstruction
- Nasal reconstruction
- External ear reconstruction followed by reconstruction of the external auditory canal and/or middle ear, if needed
- Lower eyelid surgery
- Orthodonture work to correct misaligned teeth
Prognosis
If their symptoms are managed properly, those with Treacher Collins syndrome typically grow into functioning adults with normal intelligence and average lifespans. Your pediatrician can help coordinate you with the appropriate specialists. Dr. Lauren Good is available for any and all questions regarding your child. To schedule an appointment, call the office at (540) 772-3400 or book an appointment online below.