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46-478: Treacher Collins can refer to: Treacher Collins syndrome , a rare genetic disorder characterised by craniofacial deformities. Edward Treacher Collins , the surgeon and ophthalmologist after whom the syndrome was named. Topics referred to by the same term [REDACTED] This disambiguation page lists articles associated with the title Treacher Collins . If an internal link led you here, you may wish to change

92-416: A child has a new mutation in the responsible gene and did not inherit it from either parent. In the outcome of the disease, inter- and intrafamilial variability occurs. This suggests that when an affected child is born, it is important to investigate the parents to determine whether the affected gene is present, because the parent could have a mild form of the disease that has not been diagnosed. In this case,

138-402: A child with Treacher Collins syndrome is the primary concern at birth, with other issues only addressed once respiratory function has been stabilized. Underdevelopment of the zygomatic bone gives the cheeks a sunken appearance. The external ear is sometimes small , rotated, malformed, or absent entirely in people with TCS. Symmetric, bilateral narrowing or absence of the external ear canal,

184-548: A conventional bone conduction aid has proven preferable to surgical reconstruction. The disorder can be associated with a number of psychological symptoms, including anxiety, depression, social phobia, and distress about body image. People who have this disorder may also experience discrimination, bullying, and name calling, especially when young. A multi-disciplinary team and parental support should include these issues. TCS occurs in about one in 50,000 births in Europe. Worldwide, it

230-412: A medical doctor, audiologist or audiometrist, with the result plotted separately for each ear on an audiogram . The shape of the plot reveals the degree and nature of hearing loss, distinguishing conductive hearing loss from other kinds of hearing loss. A conductive hearing loss is characterized by a difference of at least 15 decibels between the air conduction threshold and bone conduction threshold at

276-699: A mutation in this gene being found in 90–95% of the individuals with TCS. However, in some individuals with typical symptoms of TCS, mutations in TCOF1 have not been found. Investigation of the DNA has resulted in the identification of the kind of mutations found in TCOF1 . The majority of mutations are small deletions or insertions , though splice site and missense mutations also have been identified. Mutation analysis has unveiled more than 100 disease-causing mutations in TCOF1 , which are mostly family-specific mutations. The only recurrent mutation accounts for about 17% of

322-422: A mutation. The one normal copy of the gene does not produce enough protein, causing disease. Haploinsufficiency of the treacle protein leads to a depletion of the neural crest cell precursor, which leads to a reduced number of crest cells migrating to the first and second pharyngeal arches . These cells play an important role in the development of the craniofacial appearance, and loss of one copy of treacle affects

368-421: A result of a new mutation rather than being inherited. The involved genes may include TCOF1 , POLR1C , or POLR1D . Diagnosis is generally suspected based on symptoms and X-rays , and potentially confirmation by genetic testing . Treacher Collins syndrome is not curable. Symptoms may be managed with reconstructive surgery, hearing aids, speech therapy , and other assistive devices. Life expectancy

414-405: Is a genetic disorder characterized by deformities of the ears, eyes, cheekbones, and chin. The degree to which a person is affected, however, may vary from mild to severe. Complications may include breathing problems, problems seeing, cleft palate , and hearing loss . Those affected generally have normal intelligence. TCS is usually autosomal dominant . More than half the time it occurs as

460-409: Is also described. In most cases, the bones of the middle ear and the middle ear cavity are misshapen. Inner ear malformations are rarely described. As a result of these abnormalities, a majority of the individuals with TCS have conductive hearing loss . Most affected people also experience eye problems, including coloboma (notches) in the lower eyelids, partial or complete absence of eyelashes on

506-472: Is caused by deformed structures in the outer and middle ear. The hearing loss is generally bilateral with a conductive loss of about 50–70 dB. Even in cases with normal auricles and open external auditory canals, the ossicular chain is often malformed. Attempts to surgically reconstruct the external auditory canal and improve hearing in children with TCS have not yielded positive results. Auditory rehabilitation with bone-anchored hearing aids (BAHAs) or

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552-466: Is estimated to occur in one in 10,000 to one in 50,000 births. The syndrome is named after Edward Treacher Collins (1862–1932), the English surgeon and ophthalmologist who described its essential traits in 1900. In 1949, Adolphe Franceschetti and David Klein described the same condition on their own observations as mandibulofacial dysostosis . The term mandibulofacial dysostosis is used to describe

598-444: Is generally normal. TCS occurs in about one in 50,000 people. The syndrome is named after Edward Treacher Collins , an English surgeon and ophthalmologist , who described its essential traits in 1900. Symptoms in people with Treacher Collins syndrome vary. Some individuals are so mildly affected that they remain undiagnosed, while others have moderate to severe facial involvement and life-threatening airway compromise. Most of

644-464: Is inherited in an autosomal dominant manner and the penetrance of the affected gene is almost complete. Some recent investigations, though, described some rare cases in which the penetrance in TCS was not complete. Causes may be a variable expressivity, an incomplete penetrance or germline mosaicism . Only 40% of the mutations are inherited. The remaining 60% are a result of a de novo mutation , where

690-538: Is more effective that air conduction. A normal, or positive, result, is when air conduction is more effective than bone conduction. With a one-sided conductive component the combined use of both the Weber and Rinne tests is useful. If the Weber test is used, in which a vibrating tuning fork is touched to the midline of the forehead, the person will hear the sound more loudly in the affected ear because background noise does not mask

736-459: Is often associated with developmental delay and intellectual disability, more than 95% of people affected with TCS have normal intelligence. The psychological and social problems associated with facial deformity can affect quality of life in individuals with TCS. Mutations in TCOF1 , POLR1C , or POLR1D genes can cause Treacher Collins syndrome. TCOF1 gene mutations are the most common cause of

782-593: Is often first suspected with characteristic symptoms observed during a physical exam. However, the clinical presentation of TCS can resemble other diseases, making diagnosis difficult. The OMENS classification was developed as a comprehensive and stage-based approach to differentiate the diseases. This acronym describes five distinct dysmorphic manifestations, namely orbital asymmetry, mandibular hypoplasia, auricular deformity, nerve development, and soft-tissue disease. Orbital symmetry Mandible Ear Facial nerve Soft tissue A few techniques are used to confirm

828-412: Is sometimes observed. Cleft palate is also common. Dental anomalies are seen in 60% of affected people, including tooth agenesis (33%), discoloration (enamel opacities) (20%), malplacement of the maxillary first molars (13%), and wide spacing of the teeth. In some cases, dental anomalies in combination with mandible hypoplasia result in a malocclusion . This can lead to problems with food intake and

874-456: Is usually due to otitis media with effusion and may present with speech and language delay or difficulty hearing. Later onset of conductive hearing loss may have an obvious cause such as an ear infection, trauma or upper respiratory tract infection or may have an insidious onset related to chronic middle ear disease, otosclerosis or a tumour of the naso-pharynx. Earwax is a very common cause of a conductive hearing loss which may present suddenly when

920-447: The differential diagnosis , one should consider the acrofacial dysostoses. The facial appearance resembles that of Treacher Collins syndrome, but additional limb abnormalities occur in those persons. Examples of these diseases are Nager syndrome and Miller syndrome . The oculoauriculovertebral spectrum should also be considered in the differential diagnosis. An example is hemifacial microsomia , which primarily affects development of

966-614: The ability to close the mouth. Less common features of TCS may add to an affected person's breathing problems, including sleep apnea. Choanal atresia or stenosis is a narrowing or absence of the choanae , the internal opening of the nasal passages, which may also be observed. Underdevelopment of the pharynx can also narrow the airway. Features related to TCS that are seen less frequently include nasal deformities, high-arched palate, macrostomia , preauricular hair displacement, cleft palate , hypertelorism , notched upper eyelid, and congenital heart defects . Although facial deformity

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1012-407: The cases. TCOF1 is found on the 5th chromosome in the 5q32 region. It codes for a relatively simple nucleolar protein called treacle , that is thought to be involved in ribosome assembly . Mutations in TCOF1 lead to haploinsufficiency of the treacle protein. Haploinsufficiency occurs when a diploid organism has only one functional copy of a gene, because the other copy is inactivated by

1058-425: The cells' ability to form the bones and tissues of the face. POLR1C and POLR1D mutations are responsible for a minority of cases of Treacher Collins. POLR1C is found on chromosome 6 at position 6q21.2 and POLR1D is found on chromosome 13 at position 13q12.2. Those genes code for a protein subunits shared between RNA polymerase I and III. Both of these polymerases are important for ribosome biogenesis. TCS

1104-477: The clinical features. In July 1977, a New York Times article describing new plastic surgery techniques which could partially correct the appearance of those with Treacher Collins syndrome was widely circulated resulting in raised awareness of the disease. Prior to beginning his comedy career, Bob Saget made a documentary short called "Through Adam's Eyes" documenting his young nephew's experiences undergoing facial reconstructive surgery due to Treacher Collins;

1150-464: The condition, Not All Heroes Wear Capes, published in 2023. In Wonder , a children's novel , the main character is a child who has Treacher Collins syndrome. A 2017 film adaptation of Wonder , starring Julia Roberts , Owen Wilson and Jacob Tremblay , was released in November 2017. Alison Midstokke , who appears in the drama film Happy Face (2018), is an actress and activist who has

1196-417: The condition. Conductive hearing loss Common causes of conductive hearing loss include: Fluid accumulation is the most common cause of conductive hearing loss in the middle ear, especially in children. Major causes are ear infections or conditions that block the eustachian tube , such as allergies or tumors. Blocking of the eustachian tube leads to decreased pressure in the middle ear relative to

1242-562: The condition. In 2011, BBC Three returned to Jono to cover his and his partner Laura's quest to start a family, in So What If My Baby Is Born Like Me? , which first aired as part of a BBC Three season of programmes on parenting. The first film was replayed on BBC One shortly ahead of the second film's initial BBC Three broadcast. Lancaster's third BBC Three film, Finding My Family on Facebook , which looked at adoption , aired in 2011. Lancaster's memoir about living with

1288-502: The degree of stenosis and atresia of the external auditory canal, the status of the middle ear cavity, the absent or dysplastic and rudimentary ossicles, or inner ear abnormalities such as a deficient cochlea. Two- and three-dimensional CT reconstructions with VRT and bone and skin-surfacing are helpful for more accurate staging and the three-dimensional planning of mandibular and external ear reconstructive surgery. Other diseases have similar characteristics to Treacher Collins syndrome. In

1334-458: The diagnosis in TCS. An orthopantomogram (OPG) is a panoramic dental X-ray of the upper and lower jaw. It shows a two-dimensional image from ear to ear. Particularly, OPG facilitates an accurate postoperative follow-up and monitoring of bone growth under a mono- or double-distractor treatment. Thereby, some TCS features could be seen on OPG, but better techniques are used to include the whole spectrum of TCS abnormalities instead of showing only

1380-433: The disorder, with POLR1C and POLR1D gene mutations causing an additional 2% of cases. In individuals without an identified mutation in one of these genes, the genetic cause of the condition is unknown. The TCOF1 , POLR1C , and POLR1D genes code for proteins which play important roles in the early development of bones and other tissues of the face. Mutations in these genes reduce the production of rRNA, which may trigger

1426-402: The ear, mouth, and mandible. This anomaly may occur bilaterally. Another disease which belongs to this spectrum is Goldenhar syndrome , which includes vertebral abnormalities, epibulbar dermoids and facial deformities. The treatment of individuals with TCS may involve the intervention of professionals from multiple disciplines. The primary concerns are breathing and feeding, as a consequence of

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1472-477: The external ear, and this causes decreased motion of both the ossicles and the tympanic membrane. Third window effect caused by: Conductive hearing loss makes all sounds seem faint or muffled. The hearing loss is usually worse in lower frequencies. Congenital conductive hearing loss is identified through newborn hearing screening or may be identified because the baby has microtia or other facial abnormalities. Conductive hearing loss developing during childhood

1518-421: The features of TCS are symmetrical and are already recognizable at birth. The most common symptom of Treacher Collins syndrome is underdevelopment of the lower jaw and underdevelopment of the zygomatic bone . This can be accompanied by the tongue being retracted . The small mandible can result in a poor occlusion of the teeth or in more severe cases, trouble breathing or swallowing. The respiratory system of

1564-418: The film won a student Academy Award . The disorder was featured on the show Nip/Tuck , in the episode " Blu Mondae ". TLC 's Born Without a Face features Juliana Wetmore, who was born with the most severe case in medical history of this syndrome and is missing 30%–40% of the bones in her face. In 2010, BBC Three documentary Love Me, Love My Face covered the case of a man, Jono Lancaster, with

1610-415: The hearing on this side. The following table compares sensorineural hearing loss to conductive: Tympanometry , or acoustic immitance testing, is a simple objective test of the ability of the middle ear to transmit sound waves from the outer ear to the middle ear and to the inner ear. This test is usually abnormal with conductive hearing loss. A type B tympanogram reveals a flat response, due to fluid in

1656-493: The hypoplasia of the mandibula and the obstruction of the hypopharynx by the tongue. Sometimes, they may require a tracheostomy to maintain an adequate airway, and a gastrostomy to assure an adequate caloric intake while protecting the airway. Corrective surgery of the face is performed at defined ages, depending on the developmental state. An overview of the present guidelines: Hearing loss in Treacher Collins syndrome

1702-422: The jaw abnormalities. Another method of radiographic evaluation is taking an X-ray image of the whole head. The lateral cephalometric radiograph in TCS shows hypoplasia of the facial bones, like the malar bone, mandible, and the mastoid. Finally, occipitomental radiographs are used to detect hypoplasia or discontinuity of the zygomatic arch . A temporal-bone CT using thin slices makes it possible to diagnose

1748-418: The link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=Treacher_Collins&oldid=913079522 " Category : Disambiguation pages Hidden categories: Short description is different from Wikidata All article disambiguation pages All disambiguation pages Treacher Collins syndrome Treacher Collins syndrome ( TCS )

1794-467: The lower lid, downward angled eyelids, drooping of upper and lower eyelids , and narrowing of the tear ducts . Vision loss can occur and is associated with strabismus , refractive errors , and anisometropia . It can also be caused by severely dry eyes , a consequence of lower eyelid abnormalities and frequent eye infections. Although an abnormally shaped skull is not distinctive for Treacher Collins syndrome, brachycephaly with bitemporal narrowing

1840-422: The middle ear (otitis media), or an eardrum perforation. A type C tympanogram indicates negative middle ear pressure, which is commonly seen in eustachian tube dysfunction. A type As tympanogram indicates a shallow compliance of the middle ear, which is commonly seen in otosclerosis. Pure tone audiometry , a standardized hearing test over a set of frequencies from 250 Hz to 8000 Hz, may be conducted by

1886-468: The nature and location of the specific cause. In cases of infection, antibiotics or antifungal medications are an option. Some conditions are amenable to surgical intervention such as middle ear fluid, cholesteatoma, and otosclerosis. If conductive hearing loss is due to head trauma , surgical repair is an option. If absence or deformation of ear structures cannot be corrected, or if the patient declines surgery, hearing aids which amplify sounds are

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1932-458: The outer ear up to the tympanic membrane. For basic screening, a conductive hearing loss can be identified using the Rinne test with a 256 Hz tuning fork. The Rinne test , in which a patient is asked to say whether a vibrating tuning fork is heard more loudly adjacent to the ear canal (air conduction) or touching the bone behind the ear (bone conduction), is negative indicating that bone conduction

1978-508: The risk of having another affected child is 50%. If the parents do not have the affected gene, the recurrence risk appears to be low. In following generations, the severity of the clinical symptoms increases. Mutations in the main genes responsible for TCS can be detected with chorionic villus sampling or amniocentesis . Rare mutations may not be detected by these methods. Ultrasonography can be used to detect craniofacial abnormalities later in pregnancy, but may not detect milder cases. TCS

2024-711: The same frequency. On an audiogram, the "x" represents responses in the left ear at each frequency, while the "o" represents responses in right ear at each frequency. Most causes of conductive hearing loss can be identified by examination but if it is important to image the bones of the middle ear or inner ear then a CT scan is required. CT scan is useful in cases of congenital conductive hearing loss, chronic suppurative otitis media or cholesteatoma, ossicular damage or discontinuity, otosclerosis and third window dehiscence. Specific MRI scans can be used to identify cholesteatoma. Management falls into three modalities: surgical treatment, pharmaceutical treatment, and supportive, depending on

2070-447: The self-destruction (apoptosis) of certain cells involved in the development of facial bones and tissues. It is unclear why the effects of a reduction in rRNA are limited to facial development. Mutations in TCOF1 and POLR1D cause the autosomal dominant form of Treacher Collins, and mutations in POLR1C cause the autosomal recessive form. TCOF1 is the primary gene associated with TCS,

2116-414: The wax blocks sound from getting through the external ear canal to the middle and inner ear. Diagnosis requires a detailed history, local examination of the ear, nose, throat and neck, and detailed hearing tests. In children a more detailed examination may be required if the hearing loss is congenital. Examination of the external ear canal and ear drum is important and may help identify problems located in

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