Imaging in maxillofacial trauma cases

1. Imaging in Maxillofacial trauma

2. Lines used in skull radiography
The Anthropological line
• The Isometric “Baseline” which runs from the inferior
orbital margin to the upper border of the external
auditory meatus
The Orbital-Meatal Line
• The original “Baseline” which runs from the outer
canthus of the eye to the centre of the external
auditory meatus
The Interpupillary line
• The line connects the centres of the orbits and is at 90
degree to the median sagittal plane.

3. Buttress system of face
The buttress system of face is formed by
strong frontal, maxillary, zygomatic,
sphenoid and mandible bones and their
attachments to one another.
The central midface contains many
fragile bones that could easily crumble
when subjected to strong forces. These
fragile bones are surrounded by
thicker bones of the facial buttress
system lending them some strength and
stability.
These buttress represent the best
available understanding of the
mechanical support of face as they
determine how an impact is distributed
over the face

4. Plain film radiography
•To screen for facial injury
• projections are relative to
Canthomeatal line
•Proper positioning (of
patient’s head), alignment of
xray beam is critical for
evaluation because facial
skeletal anatomy is complex

5. • Remember: plain film is a 2D image of a 3D object
• Overlapping structures significantly obscure anatomic
detail. This problem is solved by standard views (to
minimize overlap, allow visualization of important
structures, familiarity for interpretation)
• Rule of symmetry: two sides of the face are quite
symmetrical
• Symmetry is usual, and asymmetry is suspect
• Multiplicity: fractures of facial bones are frequently
multiple.
• Do not stop looking for others when see one

6. Facial series
• Standard occipitomental
• 30° occipitomental
• Water’s view (PA view with
angulation)
• Caldwell view (PA view)
• Towne’s view
• Lateral view
• Submento - vertex
Mandibular series
• Orthopantogram
• Oblique view
• PA mandible
• Reverse Towne’s view
Most consistently helpful view in facial trauma is the Waters view

7. Standard Occipitomental
• The patient is positioned
facing the film with the
head tipped back so the
radiographic baseline is at
45° to the film, the so-
called nose-chin position.
• The X-ray tube head is
positioned with the
central ray horizontal (0°)
centered through the
occiput

8. • This projection shows the
facial skeleton and
maxillary antra, and
avoids superimposition of
the dense bones of the
base of the skull.
• In this projection the
petrous bones are
projected below the
maxillary antra so whole
of the lateral maxillary
wall is clear.

9. 30° OCCIPITOMENTAL
• The patient is in exactly the
same position as for the 0°
OM, i.e. the head tipped
back, radiographic baseline
at 45° to the film, in the
nose-chin position.
• The X-ray tube head is
aimed downwards from
above the head, with the
central ray at 30° to the
horizontal, centered
through the lower border of
the orbit

10. • This projection also
shows the facial skeleton,
but from a different angle
to 0° OM, enabling
certain bony
displacements to be
detected.
• This projection provides a
superior view of the
malar arches and the
anterior aspect of the
inferior orbital margins.

11. Water’s view
• The image receptor is
placed in front of the
patient and perpendicular
to the midsagittal plane
the patient’s head is tilted
upward so that the
canthomeatal line forms a
37 degree angle with the
image receptor. If the
patient’s mouth is open,
the sphenoid sinus will be
seen superimposed over
the palate.

14. McGrigor & Campbell lines
• A PATTERN OF FOUR
LINES that the eye
should follow in OM.
• USING THESE LINES
allows one to examine
all those parts of face
where fractures and
others signs are most
likely to be found and
reduces the chances of
missing a fracture

15. • Line 1-passing through the FZ
suture and across the upper edge
of the orbit
• Line 2- follows the zygomatic arch
(elephants trunk) crosses the
zygomatic bone and follows the
inferior orbital margin to opposite
side
• Line 3- passes through condyle and
coronoid process and through
lateral and medial wall of maxillary
antra on each side
• Line 4- cross mandibular ramus and
bite line
• Line 5- across inferior border of
mandible

16. Isolated zygomatic arch fracture
• Disruption of middle
McGrigor- Campbell
line is due to fracture of
right zygomatic arch
• Following the upper
and lower lines shows
no fracture

17. Tripod fracture
• The zygoma is separated
from the frontal bone at
the zygomatico- frontal
suture
• Comminuted fracture of
the zygomatic arch
• Orbital floor fracture
• Breach of the lateral wall
of the maxillary antrum

19. • Line 1 (orbital line) – fractures of lateral orbital
or diastasis of frontozygomatic suture,
fracture of orbital floor
• Line 2 (Zygomatic line)- fractures of lateral
orbit and zygomatic arch
• Line 3( maxillary line) – fractures of lateral wall
of maxillary sinus and zygoatic arch

20. Maxillary antrum fluid level
• A fluid level of blood
seen in the maxillary
antrum may be the only
obvious sign of fracture
• Th e zygomatico –
frontal suture (A) has a
variable normal
appearance
• Widening of the suture
–if seen alone-does not
indicate a fracture

21. Orbital ‘blowout’ fracture –Teardrop
sign
• On the left a ‘teardrop’
of soft tissue has
herniated from the
orbit into the maxillary
antrum

22. PA projections

23. • The patient is positioned
facing the film with the
head tipped forwards so
that the forehead and tip
of the nose touch the film
— the so-called
foreheadnose position.
The radiographic baseline
is horizontal and at right
angles to the film.

24. OCCIPITOFRONTAL 15° -20°(Caldwell
view)
• The patient is positioned
facing the film with the
head tipped forwards so
that the forehead and tip of
the nose touch the film —
the so-called foreheadnose
position. The radiographic
baseline is horizontal and at
right angles to the film.
• The X-ray tube head is
positioned with the central
ray horizontal (15-20°)
centered through the
occiput and aimed to exit
at nasion .

25. • Used to study fractures
of frontal bone, orbital
margins, zygomatico-
frontal suture and
lateral wall of maxillary
sinuses.
• The petrous ridges are
shown at a level
between the lower and
middle thirds of the
orbits

26. Towne’s view ( anteroposterior
projection)
• Technique
The base line is
perpendicular the film.
The flim is placed
posteriorly on the
occipital area of the head.
The central ray is directed
30 degree to the base line
and passes through it at a
point between the
external auditory canal

28. Lateral view of skull
• Image receptor is
positioned parallel to the
patient’s midsaggital
plane. The side of interest
placed towards image
receptor.
• The central beam is
perpendicular to mid
saggital plane and film
and centered over
external auditory meatus.

31. Submentovertex
• This projection
shows
the base of the skull,
zygomatic
• arches, sphenoidal
• sinuses and facial
• skeleton from
• below

34. Orthopantomography
• A technique for producing a single tomographic image
of the facial structures that includes both the maxillary
and mandibular dental arches and their supporting
structures.
• pantomography is derived from two words – panorama
and tomography
• Ortho - straight
• Panoramic - An unobstructed or a complete view of
the object in every direction
• Tomography – An xray technique for making
radiographs of layers of tissue in depth, without the
interference of tissue above and below that level

35. As the tubehead rotates around the patient, the x-ray beam passes through
different parts of the jaws, producing multiple images that appear as one
continuous image on the film (“panoramic view”).

36. MAIN INDICATIONS
• Evaluation of-
• Trauma
• Location of third molars
• Extensive dental or osseous disease
• Known or suspected large lesions
• Tooth development
• Retained teeth or root tips
• TMJ pain
• Dental anomalies etc.

37. POSTERO-ANTERIOR OF THE JAWS (PA JAWS/PA
MANDIBLE)
• The patient is in exactly the
same position as for the PA
skull, i.e. the head tipped
forward, the radiographic
baseline horizontal and
perpendicular to the film in
the forehead-nose position.
• The X-ray tube head is
again horizontal (0°), but
the central ray is centered
through the cervical spine
at the level of the rami of
the mandible.

38. • This projection shows
the posterior parts of
the mandible. It is not
suitable for showing the
facial skeleton because
of superimposition of
the base of the skull
and the nasal bones.

39. Main Indications
Fractures of the mandible involving the following sites:
• Posterior third of the body
• Angles
• Rami
• Low condylar necks
• Lesions such as cysts or tumors in the posterior third of
the body or rami to note any
• medio-lateral expansion
• Mandibular hypoplasia or hyperplasia
• Maxillofacial deformities.

40. Reverse Towne’s
• The patient is in the PA position, i.e. the head
tipped forwards in the forehead-nose position,
but in addition the mouth is open. The
radiographic baseline is horizontal and at right
angles to the film.
• Opening the mouth takes the condylar heads out
of the glenoid fossae so they can be seen.
• The X-ray tube head is aimed upwards from
below the occiput, with the central ray at 30° to
the horizontal, centered through the condyles.

42. Main Indications
• High fractures of the condylar necks
• Intra capsular fractures of the TMJ
• Investigation of the quality of the articular
surfaces of the condylar heads in TMJ
disorders
• Condylar hypoplasia or hyperplasia

43. Lateral Oblique view
• The Film is positioned against the patient's cheek
overlying the ascending ramus and the posterior aspect
of the condyle of the mandible under investigation.
• The Film is positioned so that its lower border is
parallel with the inferior border of the mandible but
lies at least 2 cm below it
• The mandible is extended as far as possible.
• The X-Ray tube is centered from the contralateral side
of the mandible at a point 2 cm below the inferior
border in the region of the first/second permanent
molar with angulation of 10 degrees cephalad or
caudal

45. Advanced imaging in Maxillofacial
trauma

46. Axial Plane
(Transverse)
This is an Axial
image..
…that represents
this area of
anatomy

47. Coronal Plane
Coronal Plane slices through the anatomy
from side to side.
Click

48. Sagittal Plane
Sagittal Plane is a slice through the anatomy
from front to back
Click

49. • Face
– Face (midface) is the region
from supraorbital rims to and
including maxillary alveolar
process
– Mandible, including the
temporomandibular joints
(TMJ), considered separate
from the face
– This lecture series will
include both parts (face and
mandible)

50. 3DCT FACE ANTERIOR
VIEW
Major structures
are labeled in the
picture.
Nasofrontal suture
Zygomatico frontal
suture
Zygomatico temporal
suture
SOF = Superior orbital
fissure
IOF = Inferior orbital
fissure

51. 3DCT
LEFT LATERAL VIEW

60. CHECKLIST
 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
- 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