Head and neck dev disorders Flashcards
Congenital anomalies, these do not imply?
structural defects that are present
at birth . Congenital does not i mp l y
a genetic basis
malformation syndrome
refers to multiple congenital anomolies that result from a single causative condition that simultaneously affect several tissues
Se qu enc e re fe r s to?
multiple congenital abnormalities resulting from a single causative condition that produces a sequence of downstream effects
lethality? due to? aplasia of? ears?
AGNATHIA
Lethal
Failure of migration of neural crest mesenchyme
Aplasia of mandible
Ears fused in midline
micrognathia
hypoplastic man/max
micrognathia can occur with?
1.Cleidocranial Dysplasia-Marie-Sainton Disease
2.Craniofacial Dysplasia-Crouzon Syndrome
3.Mandibulofacial Dysplasia- Treacher Collins Syndrome
4.Pierre Robin Sequence
inheritence? mutation of what gene? gene role?
C LEIDOCRANIAL DYSOSTOSIS ,
M ARIE-SAINTON D IS EASE
Autosomal dominant , but many cases are new mutations
mutation to core binding factor A1gene at 6p21, controls osteoblast dif resulting in diffuse skeletal abnormalities
CBFA1also plays a role in odontogenesis through effects on dental lamina prolif
CLEIDOCRANIAL DYSPLASIA/ MARIE-SAINTON DISEASE signs
hypoplastic clavicles
frontal bossing
midface hypoplasia
supernumerary teeth
inheritence, mutation to?
craniofacial dystosis/ crouzon syndrome
AD
mutation to FBGR2 at 10q
variable? sutures? midface? orbits?
CRANIOFACIAL DYSPLASIA/ crouzon syndrome signs
variable clinical app
Craniosynostosis - premature closure of cranial sutures
midface hypoplasia (maxilla)
Proptosis - shallow orbits
RADIOGRAPHIC CHANGES IN
CRANIOFACIAL DYSPLASIA
I n c rea sed d i git a l m a rki ngs
“Beaten metal” pattern
beaten metal pattern of craniofacial dysplasia
inheritence? mutation? defects where?
MANDIBULOFACIAL DYSPLASIA
(MANDIBULOFACIAL DYSOSTOSIS,
TREACHER COLLINS SYNDROME)
AD
mutation to 5q31. 3-32
defects to structures derived from 1st and 2nd branchial arches
MANDIBULOFACIAL DYSOSTOSIS,
TREACHER COLLINS SYNDROME) signs
hypoplastic zygoma
coloboma
ear anomolies
man hypoplasia
MANDIBULOFACIAL DYSPLASIA
(MANDIBULOFACIAL DYSOSTOSIS,
TREACHER COLLINS SYNDROME) palebral fissures
downward slanted
MANDIBULOFACIAL DYSPLASIA –
COLOBOMA OF LOWER EYELID
lack of eyelashes past this point
MANDIBULOFACIAL DYSPLASIA in subsequent generations
become more severe/ pronounced
PIERRE ROBIN SEQUENCE
(COMPLEX/SYNDROME) signs
1 . micrognathia
2 . cleft palate
3 . glossoptosis - tongue displacement
PIERRE ROBIN SEQUENCE
(COMPLEX/SYNDROME) sequence of events
1 . M a n d i b u l a r h y p o p l a s i a
2 . P a l a t a l c l e f t (failure of tongue to drop)
3 . G l o s s o p t o s i s
CLINICAL PROBLEMS IN PIERRE ROBIN SEQUENCE
Choking?
Feeding?
Breathing?
Ear?
Choking episodes
Feeding dif ficulties
Breathing dif ficulties
Ear infections
MACROGNATHIA pot. cause?
acromegaly
effects of lesion type
ACROMEGALY
A f u nc t ional p i tu itar y
a d e noma p roduc es
exc es sive g rowt h
h o rmone s e c ret ion a f ter
c l osure o f e p iphy seal
p l ates
S p ac e - oc c upying l e s ion:
▪ Hypopituitarism
▪ Visual field changes
▪ Headache
PHYSICAL FINDINGS IN ACROMEGALY
Progressive coarsening of
facial features
Enlarged nose
Mandibular prognathism
Sof t palate hyper trophy
Macroglossia
Growth of distal extremities
acromegaly
DEVELOPMENTAL DISORDERS
CAUSING FACIAL ASYMMETRY
hemifacial hyperplasia
hemifacial atrophy
hemifacial microstomia
condylar hyperplasia
segemental odontomaxillary hyperplasia - hemimaxillofacial dysplasia
HEMIFACIAL HYPERPLASIA
(FACIAL HEMIHYPERPLASIA )
A s y mmet ri c ove rg rowth of one s i d e of t h e f ac e
genetic? presentation?
HEMIHYPERPLASIA
sporadic, not hereditary
timing of presentation variable
may involve? example?
HEMIFACIAL HYPERPLASIA
may involve all tissues on affected side, including tongue, teeth, man canal
unilateral macroglossia
PROGRESSIVE HEMIFACIAL ATROPHY
name? affects what region?
romberg syndrome
unilateral atrophy of skin/soft tissue
affects CNV dermatome
COURSE OF PROGRESSIVE
HEMIFACIAL ATROPHY
Begins in first two
decades, progresses
for several years, then
stabilizes
Requires only
cosmetic treatment
PROGRESSIVE HEMIFACIAL ATROPHY
“COUP DE SABRE”
presents as a sharp demarcation on the forehead sperating the affected and unaffected sides
HEMIFACIAL MICROSTOMIA due to?
Hypoplasia of one side of the face