Treacher Collins Syndrome is a rare genetic disorder that affects the development of the facial structures. It is caused by mutations in genes that play roles in facial development. The syndrome is characterized by hypoplasia of the zygomatic bones, mandible, and other facial structures derived from the first and second branchial arches. Treatment involves a series of reconstructive surgeries throughout childhood to correct functional issues and reconstruct the facial structures. Surgical techniques discussed include mandibular distraction, zygomaticomaxillary bone grafting and distraction, and coloboma repair. Later orthognathic procedures may also be considered in selected adult patients.

1. Treacher Collins Syndrome
(Mandibulofacial dysostosis)
Dr Suiyibangbe
M.Ch Plastic and Reconstructive Surgery

2. Content
• Historical Perspective
• Introduction
• Etiopathology
• Clinical features
• Diagnosis
• Treatment and surgical technique
• Postoperative care
• Secondary management

3. Historical Perspective
• From the description by Thompson (1846) to that by Berry,
Treacher–Collins (1900), and Pires de Lima (1944), this
disease entity has been widely studied.
• Name after the eminent British ophthamologist Edward
Treacher Collins
• The French and European literature refers to this
constellation of findings as Franceschetti–Klein syndrome.
• Franceschetti and Klein described various details of this
malformation and first called it “mandibulofacial dysostosis.
• Tessier(1969) described the syndrome as the bilateral
confluence of 6, 7, and 8 clefts, which, depending on the
degree of severity, could affect the zygoma, resulting in its
hypoplasia or absence.

4. Introduction
• The abnormal development of the first and
second branchial arches.
• Treacher–Collins syndrome occurs as an
autosomal-dominant disorder in 1 per 50 000 live
births, 60% of cases arise as sporadic mutations.
• The facial profile of patients with TCS as fish-like
or bird-like.
• The orbit is egg shaped; its base is located
superomedially, and its axis is oriented
inferolaterally.
• A hypoplastic or absent zygoma is the most
characteristic finding or "central event" in TCS.

5. Cont...
• The maxilla is protrusive and overprojected.
• The mandible is often micrognathic, having a reduced
ramus and body length.
• Colobomas or pseudocolobomas of the lower eyelid
are routinely found and are pathognomonic for TCS.
• The cheek and temporal region frequently have long
and tongue-shaped sideburns that are often anteriorly
displaced and extend into the preauricular region.
• The external ear, external auditory canal, tympanic
membrane, and middle ear space have bilateral and
relatively symmetric abnormalities.
• Treacher Collins syndrome is not curable.
• Life expectancy is generally normal.

6. Etiopathology
• Treacher–Collins syndrome, or mandibulofacial
dysostosis, is a complex congenital craniofacial
malformation that most strikingly involves the
middle and lower thirds of the face.
• It is transmitted by an autosomal-dominant gene
of variable penetrance and phenotype.
• The severity of the disease increases in successive
generations.
• Advanced paternal age is considered a risk factor.
• These genetic anomalies cause bilateral defects in
structures derived from the first and second
branchial arches

7. Genetics

8. Cont...
• Mutations in TCOF1, POLR1C, or POLR1D genes can cause Treacher
Collins syndrome.
• TCOF1 gene mutations are the most common cause of the disorder,
accounting for 81 to 93% of all cases
• POLR1C and POLR1D gene mutations cause 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 the self-destruction (apoptosis) of certain cells involved
in the development of facial bones and tissues.

9. Characteristic clinical features of
Treacher–Collins syndrome
Eyelids
• Antimongoloid obliquity of palpebral fissures
• Coloboma of lower eyelids
• Dystopia of lateral canthi
• Shortening of palpebral fissure
• Absence of eyelashes
• Notching of eyebrows and upper eyelids
Orbits
• Inferior portion of lateral wall is often absent
• Inferior migration of superolateral portion of
frontal bone
Malar bone
• Hypoplastic or absent
• Absence of zygomatic arch
Maxilla
• Narrow and underprojected
• High and narrow palate
Mandible
• Hypoplastic
• Vertical occlusal plane
• Class III malocclusion with anterior open bite
• Long and retruded chin
Nose
• Protruded with a broad base
• Flattened frontonasal angle
• Narrow pharynx
Others
• Microtia and ear deformities
• Absence of external auditory canal
• Abnormalities of middle ear
• Macrostomia
• Possible velopharyngeal insufficiency

10. Cont...
• The zygomatic arches are hypoplastic or
absent, and the aponeurosis of the
hypoplastic temporal muscle is in direct
continuity with the aponeurosis of the
masseter muscle.
• According to Tessier’s classification, the
zygomatic bone is absent because of the
confluence of clefts 6, 7, and 8.

11. Fig. 39.1 (A) A 7-year-old boy with Treacher– Collins syndrome presenting with severe coloboma of the lower eyelids,
hypoplastic maxilla, underprojected and narrow maxilla. There is bilateral microtia and macrostomia. The mandible
shows severe hypoplasia, including at the menton.
(B) Three-dimensional computed tomography scan, showing the absence of the zygoma and malar bone and the lack
of the inferolateral orbital floor. The mandible has a very short ascending ramus and the posterior aspect of the maxilla
is also very short vertically.

12. Fig. 39.2 According
to Tessier, the
confluence of
craniofacial clefts 6,
7, and 8 produces
the hypoplasia or
absence of bony
structures, including
the zygoma, orbit,
maxilla, and
ascending ramus of
the mandible.

13. Prenatal diagnosis
• Mutations in the main genes responsible for
TCS can be detected with chorionic villus
sampling or amniocentesis.
• Ultrasonography can be used to detect
craniofacial abnormalities later in pregnancy,
but may not detect milder cases.

14. Radiographs
• 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.
• The lateral cephalometric radiograph in TCS shows
hypoplasia of the facial bones, like the malar bone,
mandible, and the mastoid.
• Two and three-dimensional CT reconstructions of facial
bone and skin-surfacing are helpful for more accurate
staging and planning of mandibular and external ear
reconstructive surgery.
• Diagnosis is generally suspected based on symptoms and X-
rays, and potentially confirmation by genetic testing.

15. Patient selection
• A careful physical examination is required to
ensure an adequate functional assessment of the
retropharyngeal space.
• Significant micrognathia can produce respiratory
distress, and some patients require a
tracheostomy or mandibular distraction at a very
early age.
• It is also important to assess hearing and speech.
• Dental impressions must be obtained to plan
mandibular or maxillomandibular procedures in
older patients.

16. Treatment
• 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 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

17. Cont...
• Hearing loss in Treacher Collins syndrome 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.
• Auditory rehabilitation with bone-anchored hearing
aids (BAHAs) or 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 body image disorders; people may
also experience discrimination, bullying, and name
calling, especially when young.
• Parental support.

18. Surgical management
• Surgical intervention is divided into four stages. The
first stage includes the correction of functional
emergencies when present.
• Respiratory distress is addressed with mandibular
distraction or tracheostomy very early in life.
• Corneal exposure is addressed with eyelid
reconstruction.
• The second stage of reconstruction consists of
zygomaticomaxillary reconstruction with cranial bone
grafts.
• Generally, these procedures are performed between 2
and 4 years of age.

19. Cont...
• The third stage of reconstruction, mandibular
distraction, is performed between 3 and 6 years of age.
• The goal is bilateral elongation of the ascending ramus
and closure of the anterior open bite.
• The fourth stage is distraction osteogenesis of the
reconstructed zygomaticomaxillary complexes and
lateral orbits.
• This distraction should be performed when
zygomaticomaxillary growth is observed to be the
limiting factor in global craniofacial growth. This stage
is frequently performed between 5 and 8 years of age.

20. Colobomas
• Colobomas usually occur in the lower eyelid and are
full thickness defects.
• Reconstruction should therefore include all eyelid
components.
• The most popular procedure consists of a
myocutaneous flap from the superior eyelid rotated
down to cover the defect in the inferior eyelid.
• Essentially, a Z-plasty is designed along the borders of
the coloboma, the defect is defined in the inferior
eyelid, and the superior eyelid flap is raised and
rotated into the inferior defect.
• A release of the orbital septum is mandatory to correct
the position of the lateral canthus.

21. • Fig. 39.3 (A) Procedure for coloboma correction. Planning for a simultaneous
rotation upper eyelid myocutaneous flap is outlined.
• (B) The result after the flap rotation, including the lateral canthopexy. The ligament
has been reattached 4–5 mm superior to its original insertion.

22. Zygoma
• Various alloplastic and autologous materials, including
silicone, dermis-fat grafts, cartilage grafts, and many
others, have been used with varying degrees of success for
this reconstruction.
• Many believe that calvarial bone grafts are the best option
for the reconstruction of the zygomatic arch and malar
bone.
• Some characteristic challenges of this procedure include:
the large amount of bone required, bone grafts must be
adapted to the contour of the defect, the new bone
structure must achieve the necessary projection, and
secondary bone resorption must be avoided.
• The parietal bone is the author’s preferred donor site.

23. Cont...
• A paper template is made including the malar bone,
zygomatic arch, and the lateral aspect of the orbit.
• The curvature of the donor region will be used to
achieve natural contour and projection of the new
zygomaticomaxillary structure.
• The left parietal region is used to reconstruct the right
side of the face and vice versa.
• The free bone grafts are fixed to the subjacent bone
structure at the orbit and the maxilla with 3–4 screws,
16 mm in length. This is usually sufficient for stable
immobilization.

24. Cont...
• The new zygomatic arch should reach laterally to the
bone ridge at the external auditory canal.
• In addition to the rigid fixation, the posterior surface of
the graft should have good contact with the masseter
muscle and the rest of the local soft tissues such that
bony resorption is minimized.
• In addition, a subperiosteal suspension of the cheek
soft tissues is performed with 3–4 monofilament
sutures attached to the temporalis muscle.
• The subperiosteal suspension of overlying soft tissues
adds volume to the region and produces an aesthetic
result.

26. Cont...
• In the past, composite temporoparietal flaps
had been widely used; however the muscle is
always hypoplastic and its rotation produced
secondary depression at the external
temporal fossa.
• This procedure also sacrificed precise shaping
of the osteomuscular flap to preserve
vascularity.

27. Fig. 39.6 (A) Preoperative frontal view of a 7-year-old boy presenting with all the characteristic features of
severe Treacher–Collins syndrome.
(B) Postoperative result after bilateral zygomaticomaxillary reconstruction and coloboma correction. Notice the
new structure at the bizygomatic distance. Bilateral bidirectional mandibular distraction has also
been performed.

28. Mandible
• Micrognathia in Treacher–Collins presents a
unique problem in which the mandibular
anatomy is hypoplastic in all dimensions.
• The deformity is usually bilateral, affecting
mainly the ramus and the body, both in form
and volume.

29. • Two corticotomies are
performed: a vertically
oriented one in the
mandibular body and a
horizontally oriented one in
the ascending ramus.
• Three pins are used: a central
one at the mandibular angle,
a second in the mandibular
body, and a third in the
central aspect of the
ascending ramus.
• One bidirectional distraction
device is used on each side,
each with two distraction rods
to allow independent, precise
elongation of each segment.
The central pin acts as a fixed
pivot point for distraction of
the ramus and body

31. Cont...
• With bone distraction, all tissues from skeleton to skin
are simultaneously elongated without the
inconvenience of bone grafts or tissue expansion.
• In contrast, after conventional osteotomies and bone
grafts, the contracted muscles and overlying soft-tissue
envelope act as a counterforce to the bony
advancement, often causing bony relapse and
necessitating multiple procedures to achieve optimal
aesthetic results.
• The overall functional and aesthetic results with
bidirectional mandibular distraction are satisfying.

32. Fig. 39.8 (A) Preoperative view of a 3-year-old girl with Treacher–Collins syndrome. Coloboma correction.
(B) Postoperative view at 5 years old. The bilateral bidirectional mandibular distraction has reconstructed the
inferior portion of the face. The rotation of the mandible has closed the anterior open bite.
(C) Postoperative view at 11 years old. The maxilla and the mandible show a nearly normal relationship. The
grafted zygomaticomaxillary region, however, demonstrates delayed growth. At this time the patient is
ready for zygomaticomaxillary distraction and fat injection.

33. Distraction of zygomaticomaxillary
region
• At 7–10 years of age, the grafted zygomaticomaxillary complexes
are distracted. The orbitomalar-zygomatic region can be accessed
via a coronal approach.
• An osteotomy is designed to include the zygomatic arch, the
posterior aspect of the malar bone, the inferior third of the lateral
orbital wall, and the inferior orbital rim medially to the infraorbital
foramen.
• A buried distraction device is fixed to the parietal bone, and its tip is
anchored to the posterior aspect of the malar eminence.
• After 5 days of latency, activation of the device begins at a rate of 1
mm/day. New bone formation is observed and a well-defined malar
structure is the result (Fig. 39.9).

34. Fig. 39.9 (A) Preoperative view of a 2-year-old boy with classic Treacher–
Collins syndrome.
(B) At 7 years old, after coloboma correction, zygomaticomaxillary bone
grafting, mandibular distraction, and ear reconstruction.
(C) At 16 years old: after distraction, new bone formation has produced
excellent zygomaticomaxillary volume. Two sessions of fat injection have
obtained excellent facial contour and definition.

35. Orthognathic procedures
• For selected adult patients, classical osteotomies
with a combination of midface rotation and
mandibular lengthening are still utilized.
• With a Le Fort III osteotomy, the midface is
rotated and placed in proper relationship to the
mandible using the frontonasal angle as a
fulcrum. As a result, the maxilla has a more
pronounced anterior projection.
• Unfortunately, the tight soft-tissue envelope
sometimes restricts bony repositioning and can
be a significant cause of relapse.

36. Fig. 39.10 (A) Procedure combining midface rotation and mandible lengthening as proposed by Tessier.
(B) At the first stage of the surgical procedure, the mandible is elongated and the position of the menton is
corrected.
(C) The second stage of the procedure includes the midface osteotomy, adapting the occlusion to the new
dimension of the mandible. Additional calvarial bone grafts can be added to the orbit and zygoma.

37. Postoperative care
• Orthodontic manipulation is absolutely necessary
to obtain good final functional occlusion. The use
of orthodontic elastics during the consolidation
period allows for “callus” manipulation, properly
positioning the mandible in relation to the
maxilla.
• Intraoral myofunctional devices, such as the
Fränkel III style, are used in the long term to
maintain the bone structures and teeth in an
excellent relationship.

38. Secondary procedures
• To define the final contour of the cheeks, zygomatic region,
and gonial angle, fat grafting is becoming a very important
adjunctive technique.
• In our experience, fat grafting is indicated after 15 years of
age as a final refinement of the soft tissue contour and
volume.
• Fat is harvested from the abdomen, prepared for injection,
and grafted with 2-mm cannulas.
• Fat is deposited in fine layers beginning supraperiosteally
and proceeding superficially to an intramuscular plane, and
concluding with small quantities delivered to the
subcutaneous plane.
• In each cheek 15–20 cc of fat is inserted.

39. Fig. 39.11 (A) Preoperative fontal view of a 3-year-old girl. Severe colobomas, hypoplastic
zygomaticomaxillary region, micrognathia, and anterior open bite are present.
(B) At 5 years old, after zygomaticomaxillary bone grafting and bilateral bidirectional mandibular
distraction. Notice the new bone structure at the bizygmatic areas and the inferior third of the
face.
(C) Postoperative view at 17 years old; volume has been added to the malar eminences after
distraction osteogenesis of the bone grafts. Final refinements of the facial contour have been
obtained after fat injection.

40. Key point
• Treacher–Collins syndrome is a congenital craniofacial
malformation that involves the bone and soft tissues of the
middle and lower facial thirds. Specifically, the orbits,
zygomaticomaxillary complex, and mandible are affected.
• Coloboma of the lower eyelids, inferior obliquity of the
palpebral fissures, lateral canthal dystopia, and notching of
the upper eyebrows and eyelids are characteristic.
• Surgical reconstruction should include techniques to repair
both soft-tissue and skeletal deformities.
• Parietal bone grafts are used to augment the malar
eminence. Bilateral distraction osteogenesis corrects
hypoplasia of the mandibular ramus and body with
simultaneous improvement of respiratory and digestive
function.
• Colobomas and macrostomia are repaired prior to bony
reconstruction, and microtia is treated between 9 and 10
years of age.

41. Thank you