this is medical presentation on burning surgery.

1. PREP BY :DR ZOHREH FAIZ
DIRECT BY:SP.M.JAMAL AFSHAR
AND SP.AB SAMI SAADAT
Mandibular dysostosis

2. Definition
 also known as Treacher Collins syndrome
 range between 1 in 40,000 to 1 in 70,000 of live births
 recognizable at birth
 diagnosed prenatally on US

3. emberyology
 Growth of craniofacial structures derived from the first and second pharyngeal
arch, groove, and pouch
 it is diminished symmetrically and bilaterally.
 critical period occurs sixth and seventh week

4. Anteroposterior view of 2-month-old boy
with Treacher Collins syndrome

5. Lateral view of 2-month-old boy with
Treacher Collins syndrome

6. Anteroposterior view of 2-year-old boy
with Treacher Collins syndrome

7. Lateral views of 2-year-old boy with
Treacher Collins syndrome

8. Epidemology
 Frequency
 Race
 Sex
 Age

9. Clinical Presentation
Dysmorphology and symptoms are as follows:
 Facies
 Skull
 Eyes
 Ears
 Nose
 Mouth and throat
 Mental status

10. Facies
 The face is characteristic
 bilaterally and symmetrically
 nose has a normal size
 Many time it is large (hypoplastic supraorbital rims and zygomas)
 The palpebral fissures are downward-sloping
 Cheek bones are depressed
 chin recedes with a large, down-turned mout

12. Skull
 Bones are hypoplastic(malar, zygomatic, frontal , lateral pterygoid plates,
paranasal sinuses, and mandibular condyles )
 Mastoids
 lateral margins of the orbits
 cranial base
 calvaria

13. Eyes
 palpebral fissures
 cilia

14. Ears
 pinnae are often malformed
 crumpled , misplaced toward
 meatal atresia
 EAC stenosis or atresia
 hypoplasia or agenesis of malleus and incus
 absence of the middle ear and tympanic spaces
 Extra ear tags and blind fistulas

16. Nose
 appears large (hypoplastic supraorbital rims and zygomas)
 More time is normal

17. Mouth and throat
 cleft palate
 absent soft palate
 submucous cleft palate
 parotid glands are missing or hypoplastic
 Pharyngeal hypoplasia is a constant finding
 mandibular angle is more obtuse than normal
 ramus is deficient

18. Mental status
 Intelligence is usually normal
 Developmental delay may be secondary to undiagnosed hearing loss
 Dysfunctional symptoms
 Hypoplasia and a retro positioned tongue
 Difficulties with swallowing and feeding
 Conductive hearing loss
 Impaired vision

19. Genetic
 autosomal dominant
 TCOF1, POLR1C, or POLR1D gene
 Administration of a teratogenic dose of vitamin A or isotretinoin in mice, rats, and
hamsters

20. Laboratory Studies
 ultrasonography (preferred to fetoscopy)

21. prenatal diagnosis requires
 Blood samples from family members
 Fetal cells obtained via chorionic villi sampling (10-11)
 Amniocentesis (16-17)

22. Assessment and monitoring of postnatal
functions
 Pulse oximeter monitoring
 Audiologic testing
 Neuro ophthalmologic assessment
 craniofacial CT scan (axial and coronal slices)
 Evaluation and genetic diagnosis by a medical geneticist

23. Imaging Studies
 Anteroposterior and lateral cephalography
 craniofacial CT scan
 As follow-up, CT scans from orbits through mandible (usually enough for
surgical planning)
 MRI for (IAC) study preferred
 If the clinical diagnosis of Treacher Collins syndrome is in doubt, radiological
assessment can be useful

24. Treatment & Management
 Medical Care
 immediate attention to airway and swallowing inadequacies is critical
 tracheostomy is performed
 feeding by gavage or even through a gastrostomy tube
 Fit hearing aids shortly after birth
 Family-to-family support

25. Surgical Care
 anatomic deformity and timing
 Occlusion of the oropharynx
 Distraction osteogeneses
 Tracheostomy
 tongue-lip adhesion is considered
 lateral coloboma of the lower eyelid ( skin-muscle flap from the upper lid or brow)

26.  Macrostomia, repaired with Z-plasty or straight-line skin repair
 Cleft palate
 Microtia is addressed at age 5-7 years
 A Z-plasty flap is transposed from the upper eyelid to the lower one

27. Complications
 The complications include:
 Deafness
 Blindness
 Obstructive sleep apnea
 Respiratory failure leading to death

28. Reference:
 Converse
 Medscape
 Internet