Title: Imaging OF OTOMANDIBULAR DYSPLASIA: ABOUT 10 CASES
1Imaging OF OTOMANDIBULAR DYSPLASIA ABOUT 10 CASES
A.Ben Abdallah, K.Mrad Dali, M.Omezzine,
I.Chaabani, N.Mama, K.Kadri, H.Moulahi,
K.Tlili Radiology service, Sahloul
Hospital MaxilloFacial surgery service, Sahloul
Hospital
HN14
2INTRODUCTION
- Otomandibular dysplasia is a condition in which
the lower half of one side of the face is
underdeveloped and does not grow normally. - It is sometimes also referred to as hemifacial
microsomia, first and second brachial arch
syndrome, oral-mandibular-auricular syndrome,
lateral facial dysplasia, - or otomandibular dysostosis.
- The syndrome varies in severity, but always
includes the underdevelopment of the ear and the
mandible. This is the second most common facial
birth defect after clefts
3OBJECTIVES
- To illustrate the imaging aspects of
oto-mandibular dysplasia through a study of 10
cases. - To highlight the contribution of imaging in the
preoperative assessment of the lesions of
oto-mandibular dysplasia.
4PATIENTS AND METHODS
- Retrospective study about 10 pediatric cases
- 7 boys and 3 girls,
- Aged from 5 months to 10 years old.
- All patients underwent a computed tomography scan
(CT).
5RESULTS
- CT revealed skeletal anomalies in all cases
- variable mandibular hypoplasia (n10) (table1)
- temporo-mandibular joint anomalies (n8)
- zygoma hypoplasia (n6)
- pterygoid hypoplasia (n4)
- Soft tissue anomalies (table3) muscle hypoplasia
were observed in 7 cases and parotid gland
hypoplasia in 3 cases and agenesic in 3 cases - Hypoplasia of the tympanic cavity was present in
7 patients whith ossicular anomaly in 6 cases. - Other craniofacial anomalies was seen (table2).
6Table 1
Mandible anomalies Mandible anomalies Mandible anomalies Maxillar anomalies Ear malformations Ear malformations Ear malformations Ear malformations Ear malformations Ear malformations Ear malformations Ear malformations
Ascending ramus hypoplasia Mandibar condyle TM joint deformity Reduced hight External meatal External meatal Middle ear cavity Middle ear cavity ossicles ossicles ossicles Aberrant course of the facial nerve
Ascending ramus hypoplasia Mandibar condyle TM joint deformity Reduced hight atretic hypoplasia hypoplasia absent atretic hypoplasic malformed 3
10 7 8 2 6 4 7 1 1 6 2 3
Number Others craniofacial anomalies Others craniofacial anomalies Others craniofacial anomalies Others craniofacial anomalies
Number mastoid hypoplasia Zygomatic arch hypoplasia Styloid Process hypoplasia Orbit anomalies
Number 3 6 3 2
Table 2
Number Soft tissus anomalies Soft tissus anomalies Soft tissus anomalies Soft tissus anomalies Soft tissus anomalies Soft tissus anomalies
Number Mastication muscles hyploasia Mastication muscles hyploasia Mastication muscles hyploasia Parotid gland Parotid gland Parotid gland
Number masseter temporal pterygoid hypoplasia absent present
Number 8 7 7 3 3 4
Table 3
7Case n1 A 2 years old boy
e
a
b
f
(c,d) coronal CT scan shows pterygoid process
hypoplasia (red arrow), abnormal right TM joint
(arrows) with dysplastic condylar process (e,f)
axial CT scan shows hypoplactic middle ear cavity
(arrowhead) with atretic ossicles and external
meatal atresia (arrow).
c
d
(a,b) 3D bone reconstruction reveal mandibular
ramus,condyle and coronoid process hypoplasia,
zygomatic arch hypoplasia (blue arrow) styloid
hypoplasia ( yellow arrow) and reduced high of
the maxillar ()
8Case n1
c
a
b
Coronal (a,b) and axial (c,d) CT scan show
hypoplasia of muscles of mastication masseter
(arrowhead), temporal (red arrow) and pterygoid
(yellow arrow). It shows also agenesis of the
parotid gland
d
9Case n2 8 year old boy who had malformed left
external ear since birth.
(a)3D bone reconstruction shows left mandibular
and maxillary severe hypoplasia ()with
hypoplastic zygoma arch (arrow).
a
b
c
(b,c) CT scan show an absent condylar process,
hypoplastic condyle with abnormal TM joint
(arrow) and hypoplastic pterygoid process
(arrowhead)
(d) axial CT scan reveal external meatal atresia,
agenetic middle ear with hypoplastic and
unpneumatized mastoid.
d
e
f
(e,f) axial CT scan reveal soft-tissu anomalies
hypoplastic masseter, temporal and pterygoid
muscles (arrows) and hypoplastic parotid gland
().
10Case n3 A 11 years old boy
(a,b) coronal CT scan and 3D bone reconstruction
hypoplastic mandibular condyle with TM joint
dislocation (arrow).
b
a
e
(e)axial CT scan shows minor muscles hypoplasia
(arrow) with normal parotid gland.
c
d
Coronal (c) and axial(e) CT scan agenesis of
external meatal, hypoplastic middle ear cavity,
malformated ossicles (arrow) and hypoplastic
and unpneumatized mastoid ().
11Case n4 A 9 years old boy
Axial CT scan (a,b) and 3D bone reconstruction
(c,d) mandibular condyle hypoplasia (arrow) with
normal ramus. There is an external meatal
agenesis and hypoplastis ossicles (arrowheads).
(e,f) axial and coronal CT scan show
masseter,pterygoid and temporal muscle
hypoplasia (arrows)with hypoplastic parotid
gland ()
12Cas n5 A 6 years old boy
b
a
3D bone reconstruction shows a more dramatic
appearance of asymmetric hypoplasia of the
mandible and hypoplastic zygomatic arch (a,b) CT
scan reveals hypoplastic external meatal , middle
ear cavity and ossicles (arrows)
(c,d) axial CT scan shows musles of mastication
hypoplasia (arrows) agenesis of parotid gland ()
c
d
13Case n6 A 10 years old boy
b
a
c
CT scan and 3D bone reconstruction show a left
hemifacial microsoma which associate hypoplastic
ramus (c,e) , mandibular condyle (b) with
anomaly of TM joint (b) , hypoplastic pterygoid
process( a) and zygomatic arch (e).
d
e
14Case n6
a
b
e
(e) axial CT image shows masseter muscle
hypoplasia with hypoplastic parotid gland
c
d
( a,b,c,d) axial and coronal CT images reveal
agenesis of external meatal (yellow arrow)and
middle ear constituents (red arrows) and show
an aberrant course of the 3rd portion of facial
nerve (arrowhead)
15DISCUSSION
- Hemifacial microsomia is a congenital
malformation in which there is a deficiency in
the amount of hard and soft tissue on one side of
the face. It is primarily a syndrome of the first
branchial arch, - It a syndrome involving underdevelopment of the
temporomandibular joint, mandibular ramus,
masticatory muscles and the ear - There may be cardiac, vertebral, and central
nervous system defects, in addition to
craniofacial anomalies.
16Discussion
- Otomandibular dysostosis (OMD) is the second most
common congenital facial anomaly after cleft
lip/palate with a reported incidence of about 1
in 5600 live births. - Males appear to be more frequently affected than
females (7 boys for 3 girls in our study). - It is usually unilateral (70) and always
asymetrical if it exhibits bilaterality.
17Discussion
- The phenotype is highly variable
- The clinical picture varies from slight asymetry
in the face to sever underdevelopment of one face
half with orbital implications, a partially
formed ear or even total absence of the ear. - In 48 of the cases, the condition is a part of a
larger syndrome such as Goldenhar Syndrome (when
epibulbar dermoids and vertebral anomalies are
seen along with other findings of HFM)
18Discussion
- A panoramic radiograph provides an excellent
overview of the osseous structures of the
mandible and maxillofacial complex. - The relationship of the mandible and maxilla to
the cranial base can be established initially
with a lateral cephalometric radiograph. - Computed tomography (CT) can provide both a three
dimensional rendition of the soft tissue and an
image of the under lying bone - Information on comparative muscle development can
be assessed through CT or magnetic resonance
imaging on a case by case basis.
19Imaging findings Craniofacial anomalies
- 1-Mandible
- The most obvious skeletal deformity (all our
cases), - The ascending ramus can be absent or reduced in
height. It was the most common anomaly in our
study, - The chin is deviated towards the affected side
- The mandibular condyle may be hypoplastic
- and malformed
- The TM joint deformity can range from mild
hypoplasia of the codyle with normal joint
anatomy to a grossly disorganized joint anatomy
and pseudo-articulation of the condyle at the
cranial base.
20Craniofacial anomalies
S. Pruzanskys mandible hypoplasia classification
Grade I minimal hypoplasia of mandible Grade II
functioning but deformed TM joint with anteriorly
and mdially dispalced condyle Grade III absence
of the ramus and glenoid fossa
21-
- 2-Maxillar
- Is also reduced in height, present only in 2
cases in our study - Eruption of mandible and maxillary molllars is
delayed - 3-Ear
- The meatal atresia and middle ear anomalies are
almost constant findings (from 66 to 99) (all
cases), - The external ear malformations vary from complete
aplasia to a crumpled, distorted pinna along with
ear tags - Supernumerary ear tags may occur anywhere from
the tragus to the angle of the mouth. - Middle ear cavity is small and ossicles may be
absent, hypoplastic and/or malformed - The mastoid is always hypoplastic and
unpneumatized
Craniofacial anomalies
22Craniofacial anomalies
- 4-Other craniofacial bones anomalies
- The zygoma arch may be decreased in length or
absent (60 in our study) - The mastoid process can be hypoplastic
- The styloid process may be short or absent ,
present in only 3 patients - The orbit may be reduced in dimensions and
frontal bone can be flattered - Clinical microphthalmia or anophthalmia has been
reported and the ipsilateral eye may be at a
lower level than that on the opposite side.
23Craniofacial anomalies
- 5-Extraskeletal anomalies
- Hypoplasia of facial muscles, such as the
masseter, temporal, pterygoid, and those of
facial expression on the involved side can be
observed (80 in our study) - Hypoplasia or aplasia of the parotid gland
- Narrowing of the palpebral fissure occurs on the
affected side in about 10 of patients - A coloboma of the upper eyelid is frequently
encountered - Associated cleft lip and/or palate is found in 7
of patients
24-
- Epibulbar dermoids may be seen in Goldenhar
Syndrome - Hypoplasia and / or paresis of palatal muscles
and pharynx, alongwith tongue musculature is also
reported - 6-Cranial nerve anomalies
- Sensorineural hearing loss and facial nerve
dysfunction are common - Aberrant course of the facial nerve,
- Total or partial hypoplasy of the nerve.
- Only 3 patients have aberrant course of the
facial nerve without nerve paralysis.
Craniofacial anomalies
25 Imaging findings Extrafacial anomalies
- Cranial CT scan can revel hypoplasia of cerebrum
and corpus callosum as well as hydrocephalus - Approximately, 50 of patients have congenital
heart disease - 40 to 60 of HFM patients exhibit
occipitalization of the atlas, cuneiform
vertebra, cervi cal complete or partial
synostosis of 2 or more vertebrae, supernumerary
vertebrae, spinal bifida, and anomalous ribs. - No extrafacial anomalies were seen in our study
26Imaging findings classification
- The wide spectrum of anomalies associated with
HFM has made systematic and inclusive
classification difficult. Classification of the
disease aids in diagnosis, treatment planning,
prognostic predications, and data evaluation. - the 2 popular classification systems used for
HFM, namely, the skeletal, auricular, and soft
tissue (SAT) system, and the orbit, mandible,
ear, nerve, and soft tissue (OMENS) system.
27Skeletal categories Auricle categories Soft tissue categories
S1 Small mandible with normal shape A0 Normal T1 Minimal contour defect with no cranial nerve involvement
S2 Condyle, ramus, and sigmoid notch identifiable but grossly distorted mandible strikingly different in size and shape from normal A1 Small, malformed auricle retaining characteristic features T2 Moderate defect
S3 Mandible severely malformed, ranging from poorly identifiable ramal components to complete agenesis of ramus A2 Rudimentary auricle with hook at cranial and corresponding to the helix T3 Major defect with obvious facial scoliosis, possible severe hypoplasia of cranial nerves, parotid gland, muscles of mastication eye involvement clefts of face or lips
S4 An S3 mandible plus orbital involvment with gross posterior recession of lateral and inferior orbital rims A3 Malformed lobule with rest of pinna absent
S5 The S4 defects plus orbital dystopia and frequently hypoplasia and asymmetrical neurocranium with a flat temporal fossa A3 Malformed lobule with rest of pinna absent
The skeletal, auricle, and soft tissue (SAT)
classification system of HFM
28Orbit Mandible Ear Facial nerve Soft tissue
O0 Normal orbital size position M0 Normal mandible E0 Normal ear N0 No facial nerve involvement S0 No obvious soft tissue or muscle deficiency
O1 Abnormal orbital size M1 Mandible and glenoid fossa are small with a short ramus E1 Mild hypoplasia and cupping with all structures present N1 Upper facial nerve involvement (temporal and zygomatic branches) S1 Minimal subcutaneous/muscle deficiency
O1 Abnormal orbital size M2 Mandibular ramus is short and abnormally shaped Subdivision A and B are based on relative positions of condyle and TMJ E1 Mild hypoplasia and cupping with all structures present N1 Upper facial nerve involvement (temporal and zygomatic branches) S1 Minimal subcutaneous/muscle deficiency
O1 Abnormal orbital size M2 Mandibular ramus is short and abnormally shaped Subdivision A and B are based on relative positions of condyle and TMJ E1 Mild hypoplasia and cupping with all structures present N2 Lower facial nerve involvement (buccal, mandibular, and cervical branches) S2 Moderate between the 2 extremes,S1 and S3
O1 Abnormal orbital size M3 Complete absence of ramus, glenoid fossa, and TMJ. Submental vertex views were used to distinguish mandibular type 2A from type 2B. Type O, an apparently normal mandible has not been included in previous classification systems E1 Mild hypoplasia and cupping with all structures present N3 All branches of facial nerve affected. Other involved nerves were also analyzed, eg, trigeminal N5 (sensory), hypoglossal N12 remaining cranial nerves are signified by the appropriate number in superscript S3 Severe soft tissue deficiency due to subcutaneous and muscular hypoplasmia
The orbit, mandible, ear, facial nerve, and soft
tissue (OMENS) classification system of HFM
29CONCLUSION
- The modern imaging opened a possibility of
precise exploration of oto-mandibular dysplasia - The techniques of browsing by CT scan and the
software of image processing allow to carry out a
true anatomical dissection of the whole of these
malformative syndromes - The SAT and OMENS classification systems allows
to delineate the condition of OMD to provide a
rational basis for treatment choice.