IMAGING OF SKULL FRACTURES

1. SKULL AND FACIAL
FRACTURES
By Dr. Yassera Hameed

2. What is a fracture?
• A partial or complete
break in the skull bone
and generally occurs as
a result of direct impact.
• indicates that
substantial force has
been applied to the head
and is likely to have
damaged the cranial
contents.

3. Anatomy Of The Fracture
The brain is surrounded by
1. (CSF)
2. enclosed in meningeal covering
3. and protected inside the SKULL.
The fascia and muscles
 of the scalp------------------- additional cushioning
 10 times more force is required to fracture a
cadaveric skull with overlaying scalp than the one
without

4. Anatomy of the fracture
 The skull ------
flat bones
cranial sutures.
 outer table(1.5mm)
 the spongy diploe,
 inner table(0.5mm)
 a thick, fibrous, dura mater
 shallow subdural space
 arachnoid mater that covers the
surface of the brain.
• The diploë does not form where the
skull is covered with muscles, leaving
the vault thin and prone to fracture.

5. Skull fractures are more easily sustained at
• the thin squamous temporal
• parietal bones,
• the sphenoid sinus,
• the foramen magnum,
• the petrous temporal ridge,
• and the inner parts of the sphenoid wings at the skull base.
• The middle cranial fossa
• cribriform plate, the roof of orbits in the anterior cranial fossa,
and the areas between the mastoid and dural sinuses in the
posterior cranial fossa.
THE SITES AT RISK

6. • THE ROLE OF IMAGING IS TO ASSESS
THE FRACTURE
 PATTERN,
 TYPE,
 EXTENT,
 AND POSITION
THIS IS IMPORTANT IN ASSESSING THE
SUSTAINED INJURY.

7. CLASSIFICATION OF SKULLFRACTURES
Skull fractures
LINEAR
VAULT
temporal sphenoid occipital condylar cranial fossa
BASILAR
OPEN CLOSED
Longitudinal transverde mixed
ANTERIOR;cribriform MIDDLE POSTERIOR
orbital roof
DEPRESSED

8. PAEDIATRIC
1. Growing skull fracture
2. Ping pong fracture
3. Birth fracture
4. Diastatic fracture

9. Linear fracture
 MOST COMMON
 a break in the bone but
 no displacement,
 The fracture involves the
entire thickness of the skull.
 little clinical significance
unless
involve a vascular
channel, a venous sinus
groove, or a suture.
• COMPLICATIONS include
1. EPIDURAL
HEMATOMA,
2. VENOUS SINUS
THROMBOSIS
3. SUTURE
DIASTASIS

10. Lateral skull radiograph
in a child a long, LINEAR FRACTURE extending from the midline in the occipital
region across the occipital bone into the temporal bone

11. DEPRESSED FRACTURE
 The fractured segments are displaced inward, toward the
meninges and brain for more than 3 mm. (the fragment of
bone is depressed deeper than the adjacent inner table.
 A high-energy transfer, such as a blow from a baseball bat
 is usually comminuted
 Mostly the frontoparietal region,
the bones are thin and
this part of the head is particularly prone to an
assailant's attack.
CLOSED COMPOUND/OPEN
associated with a skin laceration or when the fracture
extends into the paranasal sinuses and the middle-ear
structures

12. Compound skull fractures occur
when all layers protecting the brain
have been breached from the
meninges to the epidermis
allowing outside environmental
contact with the skull cavity

13. Sagittal CT images of an
OPEN
, COMMINUTED
,DEPRESSED SKULL
FRACTURE. Associated
Pneumocehalus (small arrows)

14. SKULL BASE FRACTURES
70% of the skull base fractures occur in the anterior fossa,
20% in the middle central skull base
5% in the middle and posterior fossa.

16. IMAGING IN SKULL FRACTURES
A. Radiography
B. Computed Tomography
C. Magnetic Resonance Imaging
D. Ultrasonography
E. Nuclear Imaging
F. Angiography

17. The American College of
Radiology (ACR)
Appropriateness Criteria

18. ACR APPROPRIATENESS CRITERIA

19. A-----RADIOGRAPHY

20. (A) SKULL RADIOGRAPHY
.A deep black and sharply defined line.
Skull radiograph in a man shows a LINEAR
TEMPOROPARIETAL FRACTURE

21. (a) skull radiography
• False positives/negatives
FRACTURE
SUTURE
1-Greater than 3 mm in width
2-Widest at the center and narrow at the
ends
3-Runs through both the outer and the
inner lamina of bone, hence appears
darker
4-Usually over temporoparietal area
5-Usually runs in a straight line
6-Angular turns
1-Less than 2 mm in width
2-Same width throughout
3-Lighter on x-rays compared
with fracture lines
4-At specific anatomic sites
5-Does not run in a straight
line
6-Curvaceous

22. LATERAL SKULL RADIOGRAPH
left-sided fracture. across the occipital and parietal
bones.
the normal bilateral squamous
temporal sutures, not to be confused with
fractures.

23. SKULLRADIOGRAPH
in a child --------- an occipital fracture. a sclerotic
margin----------- likely to be depressed.
• example of a nonaccidental injury

24. Lateral skull radiograph
in a child - a long, LINEAR FRACTURE
running across the occipital bone.
not a vessel and not a known site for a suture.

25. • a curvilinear shadow----------- a depressed fracture.

26. Postmortem radiograph in a child with multiple fractures due to nonaccidental trauma show
A diastatic fracture of the sagittal suture.

27. --- a left-sided fracture----- courses without interruption across the occipital and parietal
bones.

28. sagittal and lambdoid sutures. None
of these are fractured,
all have serrated edges.
The sutures communicate one with
another;
they are not blind ending.

29. Frontal skull
radiograph shows a
persistent metopic
suture that has not
yet fused; this is
not a fracture.

30. Vessel markings simulating a
fracture.

31. Importance of straight position of pt.. patient is malpositioned, both coronal sutures
are seen as separate entities. also the lambdoid sutures; . Accessory occipital sutures
are exaggerated by the patient's rotation.

32. (a) skull radiography
ADVANTAGES
 Skull radiographs reveal
1. Most linear fractures,
2. Show air-fluid levels in the paranasal
sinuses and cranium,
3. And delineate the craniocervical
junction well.

33. (A) SKULL RADIOGRAPHY
• do not help in assessing intracranial
complications associated with skull fractures.
In addition,
• Temporal Bone Fractures May Be Easily
Missed.

34. THE DETECTION OF A SKULL FRACTURE
ON A RADIOGRAPH
IS REGARDED AS
AN INDICATION FOR
CT EVALUATION.

35. ADVANTAGES
• MASS EFFECT,
• VENTRICULAR SIZE AND CONFIGURATION
• BONE INJURIES,
• ACUTE HEMORRHAGE.
(B) CT SCAN:-CT scanning is the modality of choice in the evaluation of
suspected skull fractures and intracranial injury.

36. CT SCAN
 an excellent modality at demonstrating
intermediate and late sequelae of head trauma,
such as
• PORENCEPHALY,
• SUBDURAL HYGROMA
• LEPTOMENINGEAL CYSTS,
• and VASCULAR COMPLICATIONS.

37. CT SCAN
• 3-D reconstructions are valuable when
evaluating facial fractures.
• Thin-section bone windows of up to 1-1.5 mm,
with sagittal reconstruction, are useful in
assessing injuries.

38. CT SCAN limitations
1. small and nonhemorrhagic lesions such
as contusion,
diffuse axonal injuries (DAIs).
2. for early demonstration of
hypoxic-ischemic encephalopathy (HIE)

39. CT SCAN
3-Temporal bone CT scanning requires
additional imaging time and patient cooperation,.
4- cannot be used to distinguish between CSF
and hemorrhage in the middle ear.

40. CT SCAN
• False positives/negatives
A linear or minimally depressed fracture may
be easily overlooked
 Basilar skull fractures are difficult to
demonstrate
In patients with shearing injury of the white
matter, a CT scan may initially be normal.

41. Axial CT scan showing AN OPEN ,NON DEPRESSED, LINEAR SKULL
FRACTURE(arrow)associated with pneumocephalus(circle).

42. Comminuted depressed skull fracture with pneumocephalus

43. COMMINUTED
DEPRESSED
FRACTURE of the
frontal sinus with
air fluid
and bone fragments in
frantal sinus
and Pneumocephalus; level
of depression greater than
width of cortex

44. Coronal CT of an open, COMMINUTED, DEPRESSED SKULL FRACTURE.
The level of depression is greater than the bony table and there are a number of bone
fragments impacted below the inner cortex of the opposing bone (large arrow).

45. C.T scan in a child -------- frontoethmoid region a COMMINUTED FRACTURE in the left
frontal bone and disruption of the left orbit with air in the orbital cavity.

46. AN OPEN
COMMINUTED AND
DEPRESSED
FRONTAL BONE FRACTURE
Contusional hemorrhage in the left
frontal lobe,
S.A.H
Temporal Extradural Hematoma(red
Arrow)
A Small Pocket Of Air
The temporal horns are slightly dilated,
suggesting the development of
Hydrocephalus.

47. Axial nonenhanced c t scan of the brain shows an OPEN COMMINUTED FRACTURE
OF THE LEFT PARIETAL BONE with an underlying extradural hematoma. Air is
tracked from the scalp tissues through the fracture into the hematoma.
FRACTURES THAT
LACERATED A MENINGEAL
ARTERY,

48. Axial brain and bone-window cT scans - multiple fractures involving the right temporal and
parietal bones, with depression

50. Bone-window cT scan shows a FRACTURE OF THE FRONTAL BONE.
the fluid level in the frontal sinus,----------------- that clotted blood is layering out.

51. SKULL BASE FRACTURES
• These are not always visible, but blood in the
sinus cavities (eg sphenoid sinus) suggests
their presence.

52. a fracture through the left
occipital bone
a haemorrhagic
contusion is seen in
the cerebellum
a fluid level in the
sphenoid sinus.

53. SIMPLE LINEAR
FRACTURE
of the skull base involving
the foramen magnum.this
injury pattern is concerning
for
i. associated spinal
fracture,
ii. cord injury or
iii. blunt cerebrovascular
injury

54. Fracture of temporal Bone

55. Fracture of temporal bone extending into foramen ovale

56. Occipital fracture extending to foramen magnum: risk of brainstem compression by
hematoma

57. A subtle temporal
bone fracture as
seen on CT

58. (A) Transverse temporal bone fracture (B) Longitudinal temporal bone fracture

59. • If the patient has clinical evidence of skull
base fracture (eg CSF rhinorrhoea /otorrhea/
bleeding from the external auditory meatus)
• A NORMAL CT DOES NOT EXCLUDE
SUCH A FRACTURE.

60. BLEEDING FROM THE EXTERNALAUDITORY MEATUS--------- A
SIGN OF SKULL BASE FRACTURE

61. BATTLE SIGN

62. PATIENT WITH RACCOON EYES.
NOTE THE TARSAL PLATE SPARING.

63. (C) MR IMAGING
LIMITATIONS
 its limited availability in the acute trauma setting,
 long imaging times,
 sensitivity to patient motion,
 incompatibility with various medical devices, and
 relative insensitivity to subarachnoid
hemorrhage.
 the risk of scanning patients with certain indwelling
devices (eg, cardiac pacemaker, cerebral
aneurysm clip) or foreign

64. (C) MR IMAGING
Advantages
 The soft tissue detail is superior to that of CT for nonhemorrhagic
primary lesions such as contusions,
 for secondary effects of trauma-------- edema and hypoxic-ischemic
encephalopathy,
 and for imaging of DAI.DAI results in characteristic lesions in
increasing order of injury severity in the: 1) cerebral white matter
and gray-white matter junction, 2) corpus callosum, particularly the
splenium, and 3) dorsal upper brain stem and cerebellum
 DIFFUSION SEQUENCES improve detection of acute infarction
associated with head injury.
 (FLAIR) images are more sensitive than conventional MR imaging
sequences for depicting of subarachnoid hemorrhage and for lesions
bordered by CSF.

65. (C) MR IMAGING
• False positives/negatives
The sensitivity and specificity of MRI in
detecting skull fractures is low, and fractures are
easily missed.

66. (D). CEREBRAL ANGIOGRAPHY, CTA, MRA
in diagnosis and management of traumatic
vascular injuries
pseudoaneurysm,
 dissection,
or uncontrolled hemorrhage

67. (E) ULTRASONOGRAPHY
Ultrasonography is a noninvasive technique
that may be useful for evaluating
• growing skull fractures
• and associated intracranial hemorrhage
in infants.
• In adults, the orbit can also be assessed for
soft-tissue injury by using sonograms.

68. (E) NUCLEAR IMAGING
• CSF rhinorrhea and otorrhea can be localized by
using overpressure cisternography with
technetium-99m (99m Tc)
diethylenetriaminepentaacetic acid (DTPA).
Single-photon emission CT (SPECT) scanning,
positron emission tomography (PET) scanning,
and transcranial Doppler ultrasonography have
complementary roles in the assessment of brain
injury.
LIMITATIONS
Cisternography with99m Tc DTPA may not be
immediately available, as this study is expensive
and cumbersome.

69. OTHER IMAGING MODALITIRS
functional imaging techniques (SPECT, PET, xenon-
enhanced CT, functional MR imaging) have a role in
assessment of cognitive and neuropsychologic
disturbances as well as recovery following head
trauma.

70. PAEDIATRIC FRACTURES

71. Growing skull fractures
• In some children, a fracture may remain un-
united and enlarge to form A GROWING SKULL
FRACTURE.
• SITES: calvarium, but rare sites are the
basiocciput and the orbital roof.
• various names such as A Leptomeningeal Cyst,
Traumatic Meningocele, Cerebrocranial
Erosion, Cephalhydrocele, Meningocele,
And Spuria.

72. Growing skull fractures
 MECHANISM OF INJURY is usually a direct force
applied to the cranial vault, resulting in the fracture, with
tearing of the dura so that cerebrospinal fluid (CSF) leaks
to form a collection. Because the CSF is under pressure
and pulsatile, a transmitted pulsation from the
subarachnoid space into the extra-axial fluid collection
causes pressure enlargement of the fracture
 CT scans, 3 types of growing skull fractures are described:
types I, II, and III.
 Type I is a GSF with a LEPTOMENINGEAL CYST, which
may be seen herniating through the skull defect into the
subgaleal space.
 Type II is characterized by a damaged lesion or GLIOTIC
BRAIN.
 In type III, A PORENCEPHALIC CYST can be seen

73. Axial CT shows
A GROWING SKULL FRACTURE---forming the leptomeningeal cyst

74. Lateral skull radiograph in a child with a growing fracture

75. Birth skull fractures
• occur as a complication of forceps or vacuum
extraction.
• simple parietal linear fractures,
• In some cases, associated extradural
hematoma,[4] subdural hematoma, or axonal
injury is observed.

76. Ping –pong skull fracture
• This is akin to a greenstick fracture of the long
bones in children.
• occurs in the first few months of life
• is usually caused by a fall when the skull hits the
edge of a hard blunt object, such as a table..
• The ping-pong skull fracture was first described
in a newborn whose head was impinging against
the mother's sacral promontory during uterine
contractions.

77. Lateral (CT) scanogram and axial bone-
window CT a temporal fracture.
slight inward bulging of the bone, but the
inner and outer tables are intact. A
CLASSIC PING-PONG
BALL

78. Diastatic Fractures
• when the fracture line transverses one or more
sutures of the skull causing a widening of the
suture
usually seen in infants and young children as the
sutures are not yet fused
• it can also occur in adults------------- usually
affects the lamboidal suture--------- does not fully
fuse in adults until about the age of 60.
• Sutural diastasis may also occur in various
congenital disorders such as cleidocranial
dysplasia and osteogenesis imperfecta.[

79. cranial
abnormalities in
cleidocranial
dysplasia
including
diastatic sutures

80. • Failure to recognize skull fracture has more
consequences than the complications resulting
from treatment.

81. Facial fractures
Fracture Type
Zygomaticomaxillary complex (tripod fracture)
LeFort
I
II
III
Zygomatic arch
Alveolar process of maxilla
Smash fractures
Other

82. • Le Fort fractures account for 10-20% of all
facial fractures

83. Le forte lines for classifying fractures of middle third of the face

85. A 3-D CT reconstruction showing a LeFort type 1 fracture
It is also known as a Guerin fracture or 'floating palate'

86. Bilateral pterygoid
fractures
Pterygoid fractures
are essential in
diagnosis of all
classic lefort
fractures.

87. Le Fort I fractures.Horizontal fracture

88. Le Fort II fractures. oblique fracture lines (arrows)--- through the orbital
floors,

89. Le Fort III -- fractures through the both
frontal sinuses.opacification of sinuses
(asterisks)---------------- represents blood.
Classic fracture lines extend through lateral
orbital walls (arrows)

90. • Only the Le Fort II fracture violates the orbital
rim. Because of this proximity to the
infraorbital foramen, type II fractures are
associated with the highest incidence of
infraorbital nerve hyperaesthesias.
• A Le Fort I fracture is characterized by a low
septal fracture, whereas a Le Fort II fracture
results in a high septal fracture.

91. • the Le Fort III fracture Because of their
location, are associated with the highest rate
of cerebrospinal fluid (CSF) leaks

92. Tri-pod fracture
Water's view. A fracture line is passing thru latral wall of max. sinus,orbital rim close to
infraorbital foramen,orbtal floor and zygomatic arch. The frontozygomatic suture is also
separated (open arrow)

93. Axial view. Fracture with depression of the zygomatic arch on the same side(arrow)

94. Axial CT scan demonstrating zygomaticomaxillary complex fracture on right
with severe displacement.

95. ORBITAL FRACTURES
BLOW-OUT FRACTURE
injury that results from blow to orbit
by object that is too large to enter orbit;
BLOW-IN FRACTURE
occurs when orbital floor fracture
segments herniate upward into orbit, impinging
on inferior orbital muscles or globe

96. Medial Wall and Orbital Floor Blowout Fractures
Herniation of the orbital fat,
Haemorrage in maxillary sinus

97. fracture of the bone beneath the right eye with eye
muscle tissue entrapped within the fracture (arrow).

98. comminuted right orbital roof "blow-in" fracture

100. THANK YOU