Rathachai Kaewlai

1. Imaging of Facial Trauma
Part 2: Pathology (Cont’d)
Rathachai Kaewlai, MD
Specialized in Body Imaging and Emergency Radiology
rathachai@gmail.com
January 2007
The author is willing to receive any input, comments and corrections,
Please do not hesitate to contact at the email address provided above. 1
Emergency Radiology: Imaging of Facial Trauma

2. Outline
• Facial and mandibular fractures
– Maxillary fractures
• Maxillary sagittal fracture
• Alveolar process fracture
• LeFort fractures
– Mandibular fractures
• Imaging approach
– Plain film
– CT
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Emergency Radiology: Imaging of Facial Trauma

3. Maxillary Fractures
• Types of maxillary fractures
– Maxillary sagittal fracture (maxillary sinus fracture)
– Palate fracture
– Alveolar process fracture
– LeFort fractures
• LeFort I fracture
• LeFort II fracture
• LeFort III fracture
• Combination (bilateral, hemi­)
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Emergency Radiology: Imaging of Facial Trauma

4. Maxillary Fractures
• Maxillary sagittal fracture
– AKA maxillary sinus fracture
– Fracture of a maxilla in sagittal plane, involving anterior­lateral wall
of a maxillary sinus (LeFort fractures represent bilateral maxillary
fractures)
– Due to direct blow to either right or left midface
– Plain film shows opacified maxillary sinus
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Emergency Radiology: Imaging of Facial Trauma

5. Maxillary Sagittal Fracture
68­year­old man was found down.
There is a sagittal plane fracture of the left maxillary sinus (red arrow)
with hemosinus (H)
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Emergency Radiology: Imaging of Facial Trauma

6. Maxillary Fractures
• Isolated alveolar process fracture
– Fracture of any portion of the alveolar process
– Clinically evident by malalignment and displacement of teeth
contained within fractured segment
– Even on CT, fracture may be subtle and easily overlooked
– Further imaging may be needed when the diagnosis is made
• X­ray of the teeth or a panoramic view (look for dental injuries)
• Chest radiograph (look for aspirated teeth)
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Emergency Radiology: Imaging of Facial Trauma

7. Maxillary Alveolar Process Fractures
Middle age women fell onto her mouth.
Red arrows show the comminuted fractures of the maxillary alveolar process
on the right side. These fractures are considered ‘open’ as they are
connected to the oral cavity.
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Emergency Radiology: Imaging of Facial Trauma

8. LeFort Fractures
• Among the most severe fractures seen in face and
associated with high­energy trauma
• Named after René LeFort, a French physician, who studied
facial fractures in cadavers. Result was published in 1901
• Key facts
– In each type, there is a partial or complete separation of maxilla
from the remainder of the facial skeleton
– All LeFort fractures must extend through posterior face,
transects the pterygoid processes
– Any combination of LeFort I, II, and III patterns can occur
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Emergency Radiology: Imaging of Facial Trauma

9. LeFort Fractures
• LeFort I fracture
– Definition: transmaxillary fracture
– Transverse (horizontal) fracture of inferior maxillae, involving
maxillary sinuses (all except superior walls), lateral margin of nasal
fossa, nasal septum and pterygoid plates
– Clinical: free floating and movable hard palate with maxillary teeth
– Imaging findings
• Opacified bilateral maxillary sinuses
• Transverse fracture through the inferior maxillae above hard palate
• Best shown and confirmed by coronal and sagittal reformatted CT
images
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Emergency Radiology: Imaging of Facial Trauma

10. LeFort I Fracture
48­year­old man was kicked by a horse.
LeFort I fracture line along bilateral maxillary sinuses (red arrows). Pterygoid plate fractures are
present (not shown). Blue arrow indicates right mandibular fracture.
H = Hemosinus
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Emergency Radiology: Imaging of Facial Trauma

11. LeFort Fractures
• LeFort II fracture
– Pyramid­shaped maxillary fracture, involving maxillary sinuses
(anterior­lateral walls), inferior orbital rim, orbital floor and
nasofrontal suture
– Clinical: free floating, movable midface including maxillary teeth,
hard palate and nose
– Imaging findings:
• Opacified bilateral maxillary sinuses and orbital emphysema
• Fractures of anterior/lateral walls of maxillary sinuses, inferior orbital
rims/floors and disruption of nasofrontal suture
• Best seen and confirmed by coronal reformatted CT images
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Emergency Radiology: Imaging of Facial Trauma

12. LeFort II Fracture
Middle age man in motor vehicle collision.
Fracture lines are demonstrated in red arrows.
Fracture of pterygoid plates are present in all
type of LeFort fractures, they are best seen in
coronal images.
H = Hemosinus
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Emergency Radiology: Imaging of Facial Trauma

13. LeFort Fractures
• LeFort III fracture
– AKA craniofacial disjunction
– This fracture separates calvaria (skull) from the facial bones
– Most severe LeFort fracture
– Definition: separation of facial bones from the skull
• Zygomas separated from sphenoid at zygomatico­sphenoid sutures
• Nasal bones and medial orbital walls separted from frontal bone at
nasofrontal sutures
• Best seen in coronal images
– Clinical: movement of face relative to the skull
– Imaging findings:
• Plain film will underestimate degree of injury due to severe soft tissue
swelling obscuring the bony details. CT is recommended
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Emergency Radiology: Imaging of Facial Trauma

14. Combined LeFort II and
III Fractures
32­year­old man, unrestrained
driver in a motor vehicle
accident.
Blue arrows define LeFort II
fracture. Red arrows define the
LeFort III fracture. Bilateral
pterygoid plate fractures are
present (not shown).
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Emergency Radiology: Imaging of Facial Trauma

15. Mandibular Fractures
• Etiology
– Motor vehicle collisions + assaults: > 80% of mandible fractures
• Incidence
– Ratio of mandibular to facial fractures = 2:1
– Co­existence of mandibular and facial fractures = 6­10%
– Rare in children
• If occurs, condyle is the most common location
• Condyle is the growth center of mandible. Trauma to this area can
retard growth and cause facial asymmetry
• Clinical
– Laceration under chin (common)
– Pain, malocclusion, deviation of mandible on opening mouth
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Emergency Radiology: Imaging of Facial Trauma

16. Mandibular Fractures
• Classification
– Mandible is divided into region for purpose of describing location of
fractures
• Symphysis (= within the boundaries of central incisors)
• Parasymphysis (within the boundaries of vertical lines distal to canine
teeth)
• Body (include the region of third molar)
• Angle (distal to the third molar)
• Ramus
• Condylar process (has separate classification system)
• Coronoid process
• Alveolar process (region normally contains teeth)
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Emergency Radiology: Imaging of Facial Trauma

17. Mandibular Fractures
• Relevant anatomy
– Mandible is a ring or arc bone which is usually difficult to break in
one location. Approximately half of mandible fracture occurs in
multiple locations.
• Search for a second fracture after initial fracture has been
identified (usually at contralateral side)
– In symphyseal, parasymphyseal fractures: Digastric, geniohyoid
and genioglossus muscles pull the symphysis downward posteriorly
– In angle fracture: 3 muscles attaching to the ramus of mandible
(masseter, temporalis and medial pterygoid) pull the proximal
fragment upward and medially
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Emergency Radiology: Imaging of Facial Trauma

18. Mandibular Fractures
• Imaging recommendation
– Plain film mandible series (PA, lateral, Towne’s and bilateral
obliques) show nearly all fractures BUT may be difficult to obtain in
multi­trauma patients
– Panoramic radiography (orthopantogram)
• Need patient in upright position
• Not optimal as a single radiograph to detect mandibular fracture
• Better to look for subtle tooth fracture
– CT
• Show all mandibular fractures AND other facial fractures (co­
existence 6­10%), as well as position and alignment of fragments
• Display associated soft tissue injuries
• Easy to perform in multi­trauma patient
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Emergency Radiology: Imaging of Facial Trauma

19. Mandibular Fractures: Missed
by Mandibular Series
Full mandible series fail to recognize
fracture/dislocation later shown in CT scan.
Red arrows = Mandibular condyles which are located
‘too anterior’ than usual
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Emergency Radiology: Imaging of Facial Trauma

20. Mandibular Fractures: Missed by Mandibular Series
Same patient as in previous page. If plain film is too be used,
CT shows left symphyseal/ parasymphyseal fracture extending to the make sure to have all
tooth (green arrows), and bilateral mandibular condyle fractures (red projections, adequate
arrows). The findings represent ‘Flail mandible’.
coverage and optimal
Limitation of plain films in previous page is likely due to 1. Inadequate
coverage (PA projection does not include the inferior part of mandible) technique. If in doubt, CT
2. Suboptimal technique (Oblique views are not true oblique) is the solution
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Emergency Radiology: Imaging of Facial Trauma

21. Mandibular Fractures
43­year­old man, fell from height, presented with Search for second site
malocclusion of fracture is
Orthopantogram demonstrates a fracture of the right warranted when one
ramus of mandible (red arrows). Subtle ‘second’ site of
sees mandibular
fracture is at the left body (green arrows) with missing
tooth ADA #19 which is confirmed in CT scan (next fracture
page).
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Emergency Radiology: Imaging of Facial Trauma

22. Right Sagittal
Mandibular Fractures
Same patient as in previous page.
CT confirms the fractures of the right angle of mandible (red arrows) and left body (green
arrows). Axial image shows extension of fracture into the root of the left mandibular
tooth, indicating an open fracture
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Emergency Radiology: Imaging of Facial Trauma

23. Mandibular Fractures ­ Missed by Orthopantogram
21­year­old man was punched at his left face by the right­handed.
Orthopantogram shows a nondisplaced fracture of the left angle of mandible (red
arrows), extending to the root of unerupted ADA #18.
Where is the second site of fracture?
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Emergency Radiology: Imaging of Facial Trauma

24. Mandibular Fractures ­ Missed by Orthopantogram
Same patient as previous page.
CT Orthopantogram (post­processing images from axial CT) shows an additional
nondisplaced fracture of the left parasymphysis (blue arrows).
Plain orthopantogram should not be used as a single imaging to look for
mandibular fractures. It is useful for tooth fracture, not for mandible.
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Emergency Radiology: Imaging of Facial Trauma

25. A B
Mandibular Fractures with TMJ Dislocation
19­year­old woman in a rollover motor vehicle collision.
Axial CT image (A) shows ‘empty glenoid sign’ (red line) indicating right temporomandibular joint
dislocation. Image B (inferior to A) revealed a fracture of the right mandibular condyle (red arrow)
with anterior medial displacement of the condyle due to the pull of lateral pterygoid muscle. The
left glenoid fossa is normal.
C = Left condyle of mandible
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Emergency Radiology: Imaging of Facial Trauma

26. Mandibular
Fractures with TMJ
Dislocation
Same patient as in previous
page.
3D reconstruction image
on right lateral view
makes it easier to
understand the fracture
site, dislocation and
orientation of the
fragment.
Red arrows = fracture of the
base of right condyle of
mandible
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Emergency Radiology: Imaging of Facial Trauma

27. Mandibular Fractures with Tooth Fracture
Young man in a motor vehicle accident.
Tooth fracture of ADA #29 is apparent (blue arrow) in this orthopantogram. However,
fracture of the right body of mandible is very subtle (red arrow) and may be detected
only retrospectively. This confirms that orthopantogram is not an appropriate
imaging technique to rule out or characterize mandible fractures.
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Emergency Radiology: Imaging of Facial Trauma

28. Mandibular Fractures with Tooth Fracture
Same patient as in previous page.
In this case, CT demonstrates comminuted fracture of the right body of mandible
(red arrow) and tooth fracture (blue arrow). With tooth fracture, orthopantogram and
dedicated tooth radiograph are an appropriate and optimal technique.
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Emergency Radiology: Imaging of Facial Trauma

29. Imaging Approach ­ Plain Film
• Friendly line (anterolateral antral wall of maxillary sinus)
– Both intact
• NO ZMC or LeFort fractures
• Blowout fracture
• Isolated fractures of lateral orbital wall, zygomatic arch
– One disrupted
• ZMC fractures
• Maxillary sagittal fracture (isolated sinus fracture)
– Both disrupted
• LeFort fractures
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Emergency Radiology: Imaging of Facial Trauma

30. Imaging Approach ­ CT
• Clear sinus sign (= all sinuses and mastoid are clear of fluid)
– Nasal bone fractures
– Isolated zygomatic arch fractures
– Orbital roof/lateral wall fractures
– Mandible fractures
• Hemosinuses
– Pterygoid plate fracture present ­ probable LeFort fracture
• With fracture of lateral margin of nasal fossa = LeFort I
• With fracture of inferior orbital rim = LeFort II
• With fracture of zygomatic arch = LeFort III
– Maxillary wall fractures
– Orbital floors, NOE region fractures
– ZMC fractures
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Emergency Radiology: Imaging of Facial Trauma

31. Checklist for Facial Radiograph/CT
 Treat life­threatening injury first (ABC of trauma)
 CT is more accurate, faster to do than plain film and can be
performed at the same time as trauma head CT
 Emergency in face injury
 Airway compromise due to severe soft tissue swelling,
fracture or obstructed foreign body
 Life threatening hemorrhage can be from nasal injury
 Facial fractures that compromise vision
 Orbital apex fracture may injure optic nerve, requiring urgent Rx
 Entrapment of intraocular muscle requires urgent Rx
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Emergency Radiology: Imaging of Facial Trauma

32. Checklist for Facial Radiograph/CT
 Facial structures are quite symmetrical
 Do not stop searching when see one abnormality
 If suspect for more than simple nasal fracture, do CT
 Significant (but can be subtle) fractures
 Fracture involves the optic foramen which can cause permanent
visual loss if not treated promptly
 Fracture of the posterior wall of frontal sinus requires
neurosurgical evaluation and may require antibiotics prophylaxis
 Fracture/dislocation of the TMJ usually missed on initial survey. It
can cause significant disability if left untreated
 Look for significant soft tissue injuries
 Globe rupture, hemorrhage
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Emergency Radiology: Imaging of Facial Trauma

33. • The information provided in this presentation…
– Does not represent the official statements or views of the Thai
Association of Emergency Medicine.
– Is intended to be used as educational purposes only.
– Is designed to assist emergency practitioners in providing
appropriate radiologic care for patients.
– Is flexible and not intended, nor should they be used to establish a
legal standard of care.
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Emergency Radiology: Imaging of Facial Trauma