Trauma craniofacial

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Traumatismo Craniano 
Encefálico 
Facial 
Skull fracture 
• Caused by direct impact to the skull. 
• Marker for underlying brain injury as this requires a 
substantial force. 
• Classified as linear, depressed or basal. 
• Type depends on amount of force applied and the ratio 
of force to the impact area. 
• Clinically difficult to detect. If detectable there is likely 
to be underlying brain injury. 
• Increased significance if an open fracture, or if the 
fracture communicates with an air sinus, is depressed or 
crosses an artery or major dural sinus. 
• Beware Non-accidental injury; commonest cause of 
skull fracture in an infant. 
Radiological features 
• Plain skull radiographs are the initial investigation with 
some progressing to CT. 
• Linear fractures will appear as a deeply black sharply 
defined line. May be mistaken for a suture line or vascular 
groove. A vascular groove often branches, has a sclerotic 
margin and a typical site. 
• Depressed fractures are often difficult to see. Look for 
increased or double density related either to bony overlap or 
if the fracture has being imaged tangentially. 
• Basal skull fractures are not well seen on plain radiographs. 
Look for fluid level within sphenoid sinus. If suspected the 
patient should have a CT. 
• CT will often demonstrate skull fractures when viewed on 
bony windows. More useful for visualisation of secondary 
complications. 
 
• Look closely at the initial scout image as this may 
demonstrate a fracture. 
• Soft tissue swelling, or an underlying brain 
abnormality, may be associated with a fracture. 
• Fractures may be missed if appropriate „window‟ 
parameters are not chosen. Always assess for fractures 
on bony windows. 
• Fractures appear as sharply defined lines and should not 
be mistaken for a suture or vascular groove; a vascular 
groove often branches and both have typical sites. 
• The presence of intracranial air may be secondary to an 
open fracture or connection with an air-containing 
sinus. 
(a) Depressed skull fracture (arrowheads) with (b) CT correlation (different patient). (a) Depressed skull fracture (arrowheads) with (b) CT correlation (different patient). 
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Simple vault fracture (arrowheads). 
Base of skull fracture (arrows). 
Left parietal bone fracture 
(arrowheads) with marked 
overlying 
soft tissue contusion. Depressed skull fracture 
(arrow). 
Base of skull fracture (arrows). 
Complex vault fracture (arrows). 
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Bilateral comminuted temporal 
bone 
fractures (arrows). 
Classification of Head Injury 
• Traumatic head injury can be divided into primary and 
secondary forms. Primary lesions are those that occur as a 
direct result of a blow to the head. Secondary lesions occur 
as a consequence of primary lesions, usually as a result of 
mass effect or vascular compromise. Secondary lesions are 
often preventable, whereas primary injuries, by definition, 
have already occurred by the time the patient arrives in the 
emergency department. 
• Primary lesions include epidural, subdural, subarachnoid, 
and intraventricular hemorrhage, as well as diffuse axonal 
injury (DAI), cortical contusions, intracerebral hematomas, 
and subcortical gray matter injury. Direct injury to the 
cerebral vasculature is another type of primary lesion. 
• Secondary lesions include cerebral swelling, brain 
herniation, hydrocephalus, ischemia or infarction, CSF leak, 
leptomeningeal cyst, and encephalomalacia. 
Cerebral contusion 
• Commonest form of traumatic intra-axial injury. 
• Contusions occur at the inferior and polar surfaces of 
the frontal and temporal lobes. 
• Injury results secondary to contact with bony surfaces 
during deceleration and is produced by damage to 
parenchymal blood vessels leading to petechial 
haemorrhage and oedema. 
• Contusions develop in surface grey matter tapering into 
white matter. 
• Injuries may be coup or contra-coup. 
• Cerebral contusions are also produced secondary to 
depressed skull fractures and are associated with other 
intracranial injuries. 
Radiological features 
• Non-contrast computed tomography (CT) useful 
in the early posttraumatic period. 
• Contusions are seen as multiple focal areas of low 
or mixed attenuation intermixed with tiny areas of 
increased density representing petechial 
haemorrhage. 
• True extent becomes apparent over time with 
progression of cell necrosis and oedema. 
• Magnetic resonance imaging (MRI) is the best 
modality for demonstration of oedema and 
contusion distribution. 
CT features 
• Location 
– Often multiple bilateral lesions at the interface between grey and white 
matter. 
– Commonly along anterior, lateral and inferior surfaces of frontal and 
temporal lobes. 
– Less frequently seen in parietal and occipital lobes and the posterior 
fossa. 
• CT sensitive for haemorrhage in the acute post-traumatic period. 
• The site of scalp swelling often indicates the site of the coup injury. 
• Focal/multiple areas of low attenuation, representing oedema, are 
intermixed with tiny areas of increased density, representing 
petechial haemorrhage. 
• In children, a common appearance is of diffuse cerebral swelling 
without haemorrhage in the acute post-traumatic period. 
• True extent becomes apparent over time with progression of cell 
necrosis, oedema and mass effect. 
Cerebral contusions in both 
frontal lobes (arrows). The 
adjacent low 
density represents local 
oedema. 
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Hemorrhagic contusion in the 
superior frontal gyrus, 24 hours 
old. Axial CT. 
Bifrontal hemorrhagic contusion 3-4 days old. Axial T2WI (a) and axial T1WI(b). 
Loss of signal due to susceptibility artifact on T2W2(a). Hyperintense signal 
(methemoglobin) on T1WI(b) 
Multi-focal contusions 
within both 
frontal lobes, with 
additional acute 
subarachnoid 
haemorrhage on the 
tentorium (arrowheads). 
Marked left 
fronto-parietal soft tissue 
swelling 
(astrerisk). 
Subtle left parieto-
occipital 
contusions. 
Large contusions in the right 
frontal 
and temporal lobes. 
Right temporal contusions, with 
subtle 
high density subarachnoid 
blood 
outlining sulci posteriorly 
(arrow). 
Note the adjacent 
subcutaneous soft 
tissue and left frontal swelling. 
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Extradural haematoma 
• The majority of these are arterial (middle meningeal 
artery) with a small proportion being of venous origin. 
• Commonly unilateral and associated with a fracture in 
adults. Skull fractures are often absent in children due 
to skull elasticity. 
• Haematoma forms between the inner table of skull and 
the dura. 
• May have associated injuries, such as a subdural 
haematoma (SDH) or contusions. 
• Arterial bleeding usually develops and presents rapidly 
within 1 hour of injury whereas venous haematomas 
may present after several days. 
Radiological features 
• CT signs include a biconvex hyperdense elliptical 
collection with a sharply defined edge. Mixed 
density suggests active bleeding. 
• The haematoma does not cross suture lines. 
• May separate the venous sinuses/falx from the 
skull; this is the only type of haemorrhage to do 
this. 
• Mass effect depends on the size of the 
haemorrhage and associated oedema. 
• Venous bleeding is more variable in shape. 
• Associated fracture line may be seen. 
Lentiform-shaped high 
density left extradural 
haematoma (arrows). Note 
the contra-coup right 
temporal contusions 
(arrowheads). 
Subarachnoid haemorrhage 
• Spontaneous subarachnoid haemorrhage (SAH) 
usually occurs secondary to a ruptured aneurysm 
or arteriovenous malformation. 
• Acquired aneurysms are commonest in the circle 
ofWillis;at bifurcations with turbulent flow. 
• Commonest before 50 years of age, but may occur 
at any age. 
• Free blood causes irritation of the meninges. 
• A sentinel headache occurs in roughly two-third 
of patients heralding a future bleed. 
Radiological features 
• Non-contrast CT is sensitive within 4–5 hours 
of onset. 
• Look for acute haemorrhage (increased 
density) in the cortical sulci, basal cisterns, 
Sylvian fissures, superior cerebellar cisterns 
and in the ventricles. 
• MRI is relatively insensitive within the first 48 
hours but is useful after this time and in 
recurrent bleeds to pick up subtle haemosiderin 
deposition. 
Multiple areas of linear high 
density are seen within the 
right cerebral sulci (arrows); 
these represent areas of 
acute subarachnoid 
haemorrhage. 
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Subdural haematoma 
• SDH commonly occurs in the elderly and in 
children (beware NAI). 
• Occur in the subdural space, i.e. the potential 
space between pia arachnoid membrane and dura. 
• Caused by traumatic tearing of bridging veins in 
the subdural space. 
• Often secondary to deceleration injuries, or direct 
trauma in which there is movement of the brain in 
relation to the skull. Beware forceful coughing/ 
sneezing or vomiting in the elderly. 
• No consistent relationship to skull fractures. 
Radiological features 
• CT shows a crescentic fluid collection between 
the brain and inner skull. Concave inner 
margin with minimal brain substance 
displacement. 
• Crosses suture lines but not dural reflections. 
• In the acute phase the fluid collections appear 
to be of high density; in the subacute phase (2–
4 weeks post-injury) the collection is isodense 
to brain and in the chronic phase (4 weeks 
post-injury) the collection is of low density. 
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Herniation Syndromes 
• CT systems with multiple detectors allow multiplanar reconstructions that visualise the displacement 
of brain tissue. 
• Subfalcial herniation: Most common herniation syndrome 
– The septum pellucidum is displaced to the contralateral side (semiconvex course) 
– There is a risk of obstructed flow of CSF due to blockage of the interventricular foramen of Monro (the width 
of the temporal horns is a sensitive sign of this). 
• Transtentorial herniation: Displacement of portions of the midbrain inferiorly through the tentorium 
– Narrowing or complete occlusion (obliteration) of the cisterna ambiens 
– Usually with midline displacement Obstructed flow of CSF due to compression of the sylvian aqueduct. 
• Tonsilar herniation: Infratentorial mass effect 
– Displacement of the cerebellar tonsils inferiorly through the foramen magnum Obliteration of the prepontine 
cistern 
– The perimedullar halo of CSF is no longer present in the foramen magnum Obstructed flow of CSF due to 
compression of the sylvian aqueduct and the fourth ventricle. 
• MRI findings 
– This modality is the second choice due to the time it requires 
– Multiplanar imaging can visualize the herniation syndrome in all planes 
• Secondary sequelae that can be visualized include: microhemorrhages (T2*-weighted images), 
cranial nerve lesions (T1-weighted gradient echo sequences after injection of contrast agent), 
hypoxic brain damage (diffusion-weighted images). 
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Facial fractures 
• Often secondary to assault in adults and falls in 
children. Facial fractures in children are 
suspicious of non-accidental injury (NAI). 
• Emphasis on diagnosis rather than specific 
treatment in accident and emergency 
(A&E).Functional loss and disability can be 
significant following facial trauma. 
• Consider cervical spine injury in all. 
• Classified according to site – maxillary (sub-
classified by Le Fort), malar, infra-orbital, 
mandibular and nasal. 
Le Fort classification 
Le Fort fracture classification 
• type 1 
– horizontal maxillary fracture, separating the teeth from the upper 
face. 
– fracture line passes through the alveolar ridge, lateral nose and 
inferior wall of maxillary sinus. 
• type 2 
– pyramidal fracture, with the teeth at the pyramid base, 
and nasofrontal suture at its apex 
– fracture arch passes through posterior alveolar ridge, lateral 
walls of maxillary sinuses, inferior orbital rim and nasal bones. 
• type 3 
– craniofacial disjunction 
– fracture line passes through nasofrontal suture, maxillo-frontal 
suture, orbital wall and zygomatic arch. 
Additional tips 
 
• if the anterolateral margins of the nasal fossa 
are intact it excludes a type 1 fracture. 
• if the infraorbital rims are intact it excludes a 
type 2 fracture. 
• if the zygomatic arch is intact it excludes a 
type 3 fracture. 
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Mid-face fracture – Le 
Fort II.Additional 
diastasis of the left 
zygomaticofrontal 
suture (arrow). 
Maxillary 
• Commonly associated with massive facial trauma and other 
organ trauma. Presents with massive soft tissue swelling, 
mid-face mobility and malocclusion. Cerebrospinal fluid 
(CSF) rhinorrhoea may occur secondary to dural tears. 
• Significant epistaxis can occur compromising both airway 
and circulation and can require intervention. 
 
• Radiological features 
• Request facial views. Fractures can be difficult to see. 
• CT scan often of benefit to delineate number and extent of 
fractures. Helpful in planning surgery and subsequent 
follow-up. 
• Fractures rarely occur in their pure form and are often 
asymmetrical. 
Malar 
• The zygoma may fracture in isolation or more 
commonly extend through to the infra-orbital foramen 
with disruption of the zygomaticotemporal and 
zygomatico-frontal sutures (tripod fracture). 
• Look for cheek flattening, a palpable step, infra-orbital 
nerve damage and diplopia. 
• Intra-oral examination may reveal bony irregularity 
above and behind the upper molars. 
 
• Radiological features 
• Facial views supplemented by submentovertex (SMV) 
views to visualise the zygomatic arches. 
Left zygomatic arch fracture. 
Infra-orbital (blow out) fracture 
• Enophthalmos and orbital emphysema may be evident. 
Diplopia may occur secondary to ocular muscle (or orbital 
fat) entrapment. 
• Globe injuries not uncommon, e.g. retinal detachment. 
 
• Radiological features 
• Facial views may show a „teardrop‟, representing soft 
tissue, herniating into the maxillary sinus. Complete 
opacification of the maxillary sinus occurs secondary to 
haemorrhage and oedema and, if unilateral, should be 
considered to be a secondary fracture until proven 
otherwise. 
• Depression of the orbital floor may be visible. 
• Air within the soft tissues may be seen with orbital 
emphysema. 
Infra-orbital fracture. (a) 
‘Teardrop’ sign. (b) Coronal CT 
demonstrating 
the same. 
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Infra-orbital fracture. (a) 
‘Teardrop’ sign. (b) Coronal CT 
demonstrating 
the same. 
Mandibular 
• Pain and tenderness and a palpable step may be evident. 
Malocclusion common. May fracture distant to point of 
impact. 
• Lip numbness suggests inferior dental nerve damage. 
 
• Radiological features 
• Confirm with a panoramic view (orthopantomogram, 
OPG) with combined antero-posterior (AP) views. 
• Condylar views may show a fracture or 
temporomandibular joint (TMJ) dislocation. Coronal 
CT is of benefit in difficult to visualise condylar 
fractures. 
OPG: Fractures of right body and left ramus of mandible. 
Caso 01 
•36 year-old with severe headache 
 
Opções 
• Epidural hematoma 
• Subdural hematoma 
• Glioblastoma multiforme 
• Diffuse axonal injury 
• Subarachnoid hemorrhage 
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Subarachnoid Hemorrhage (SAH) 
• Bleeding into the subarachnoid space, between 
the pia mater and the arachnoid 
• Clinical findings 
– Headache is most common symptom 
– Frequently reported as severe (“worst headache of 
life"), of abrupt onset, reaches maximum intensity 
within seconds (“thunderclap headache”) 
– Nausea 
– Vomiting 
– Change in mental status -- confusion 
– Decreased level of consciousness including coma 
– Spinal fluid may be bloody 
 
Imaging findings 
• Unenhanced CT of the brain is the study of choice for establishing presence of SAH 
• Acute hemorrhage is most evident 2-3 days after the acute bleed 
• CT angiography and MRA have replaced conventional angiography in most institutions for the 
identification and location of the aneurysm itself 
• Acute hemorrhage appears as high-attenuation (white) material that fills the normally black 
subarachnoid spaces, which include 
– The basilar cisterns 
• Especially the suprasellar cistern 
– The sulci 
• Especially the Sylvian fissures 
– Over the convexities of the brain, SAH produces white, branching densities representing the normally black 
sulci filled with blood 
• During the subacute period (days to weeks after acute bleed), look for 
– Decreased visualization of the normally “black” fluid within the sulci and basal cisterns 
– Enlargement of the ventricles 
• From communicating hydrocephalus 
• False positives may occur by mistaking normal visualization of the falx cerebri and tentorium 
cerebellifor SAH 
• MR angiography is useful in identifying the location of aneurysms 
• Cerebral angiography is used for the detection of intracranial aneurysms 
– Such features as aneurysm size and shape can help determine which aneurysm has bled 
– Still considered the “gold” standard for diagnosis of intracranial aneurysm 
Subarachnoid hemorrhage 
(SAH). There is high-attenuation 
blood in the Sylvian fissures 
(blue arrows) and the 
interhemispheric fissure (red 
arrow) seen on this non-contrast 
enhanced CT of the brain. Do 
not confuse normal, physiologic 
calcifications (white and black 
arrows) for blood. 
Caso 02 
• 3 month-old with swallowing difficulties 
Opções 
• Normal Convolutional Markings 
• Sarcoid 
• Neuroblastoma 
• Lacunar Skull 
• Fibrous Dysplasia 
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Lacunar Skull / Luckenschadel 
Skull 
• Bone dysplasia of skull consisting of multiple 
oval lucencies separated by dense, bony ridges 
• Associated with 
– Neural tube defects, especially myelomeningocele 
– Chiari II malformation 
– Encephalocele 
• Not related to degree of concomitant 
hydrocephalusInner table more affected than 
outer. 
Imaging Findings 
• Well-defined lucent areas in calvarium 
representing nonossified fibrous bone 
• Lacunae are bounded by normally ossified 
bone 
• Most prominent in parietal bones 
• Small posterior fossa associated with Chiari II 
malformation 
• Lacunar Skull. There are multiple focal areas 
of radiolucency in the skull (white arrows) 
bounded by more normal, dense bony ridges. 
The child had a known myelomeningocele. 
Caso 03 
• 29 year-old unable to close mouth 
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Opções 
• Maxillary Sinusitis 
• Dislocation of Mandible 
• Fracture of Mandible 
• Dentigerous Cyst 
• Enlarged Adenoids 
Dislocations of the Mandible 
• Clinical findings 
• Dislocations of the mandible tend to be 
uncomfortable but not severely painful for the 
patient 
– The presence of a fracture increases the pain 
• Patients are unable to close mouth completely 
• Difficulty speaking and, possibly, swallowing 
• Dislocations may be unilateral or bilateral 
– Prognathic appearance to jaw when both are 
dislocated 
Imaging findings 
• Conventional radiography is usually diagnostic 
• Mandibular condyle lies anterior to the 
articulate eminence on one or both sides 
Dislocated mandible. Both 
mandibular condyles 
(labeled M) are dislocated 
anterior to 
their respective mandibular 
fossae (red and black 
arrows) in the temporal 
bones. The blue arrow 
points to the articular 
eminence which prevents 
the mandibular condyle 
(black M) from relocating 
in the mandibular fossa 
(black arrow). 
Caso 04 
 
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Le fort fractures 
• All Le fort fractures involve the pterygoid 
processes. The type II Lefort fracture line passes 
vertically through the maxilla from posterior 
alveolar margin to the medial orbital rim, over the 
bridge of the nose and down the other side. The 
midface is separated from the rest of the skull and 
is typically depressed (see angled image). The 
presence of a Lefort fracture implies a large force, 
and imaging of the brain and cervical spine 
should also be performed. The airway is at risk, 
particularly with Lefort III fractures, and 
intensive airway management is required. 
Caso 05 
• A 50-year-old male patient was brought by the 
ambulance to the emergency department after 
a fall on the face, which was extremely 
swollen with multiple bruises and haematomas 
raising the possibility of a midface fracture. 
 
3-D CT-
Reconstruction 
image of the skull 
 
A midface fracture 
starting at 
zygomaticofrontal 
suture (blue arrow), 
running posteriorly 
through medial wall 
of the orbit (blue 
arrowheads) and 
passing through the 
nasofrontal 
suture (green 
arrow). Also fracture 
of the zygomatic 
arch (red arrow). 
Axial non-enhanced CT image of the paranasal sinuses 
Bilateral fracture of the lateral wall of maxillary sinus (blue arrowheads) as well as 
medial wall (red arrowhead). Fracture of the nasal septum is also seen (green 
arrowhead). Bilateral haematosinus (yellow asterisk). 
Axial non-enhanced 
CT image of the 
paranasal sinuses 
 
The red arrow shows 
associated 
nasoethmoid fracture. 
3-D CT-
Reconstruction 
image of the skull 
(view from below) 
 
Both red arrows 
show bilateral non-
displaced fracture 
of the zygomatic 
arch which is a 
characterstic 
feature for this type 
of fractures. 
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Coronal non-
enhanced CT 
image of the 
paranasal 
sinuses 
 
The blue arrows 
show bilateral 
fracture of the 
pterygoid 
processes, which 
is a common 
association in all 
three types of Le 
Fort fractures. 
Coronal non-enhanced CT image of 
the paranasal sinuses 
 
This section shows that orbital floor 
is bilaterally intact (red arrows) thus 
excluding Le Fort 
II fracture. 
Diagramatic illustration of the different planes of Le Fort fractures 
A. Le Fort I: involves the anterolateral margin of the nasal fossa above the 
maxillary alveolar process. 
B. Le Fort II: involves the inferior orbital rim. 
C. Le Fort III: involves the zygomatic arch. 
Steps of diagnosis 
• 1. Always look at the pterygoid processes (coronal images). 
A fracture of the pterygoid processes almost always 
indicates that there is at least one of the Le Fort fractures. 
• 2. To classify the type, look at the three bony structures that 
are unique to each type: 
– Anterolateral margin of the nasal fossa (type I), 
– Inferior orbital rim (type II), 
– Zygomatic arch (type III). 
• If one of these structures is intact, the corresponding type of 
Le Fort is excluded. 
• 3. If one of the Le Fort fractures is suspected because of a 
break in its unique component, it should be confirmed by 
identifying the other fractures that are expected in the plane 
of that type of fracture. 
Diagnóstico 
• Final Diagnosis 
– Le Fort III Fracture of the Skull (Craniofacial 
Disjunction)• Differential Diagnosis List 
– Le Fort II Fracture, Le Fort I Fracture 
Referências 
 
• BRANT, William E.; HELMS, Clyde A. (Ed.). Fundamentals of diagnostic 
radiology. Lippincott Williams & Wilkins, 2012. 
• CONDER, GABRIEL; RENDLE, JOHN; MISRA, RAKESH R.; KIDD, SARAH. 
A–Z of Emergency Radiology. Cambridge University Press, 2009. 
• HOLMES, Erskine J.; MISRA, Rakesh R. AZ of emergency radiology. Cambridge 
University Press, 2004. 
• JUHL, John H.; CRUMMY, Andew B.; KUHLMAN, Janet E. Interpretação 
radiológica. Interpretação radiológica, 2000. 
• SARTOR, Klaus. Brain Imaging (Direct Diagnosis in Radiology). Thieme, 2012. 
• WEBB, Wayne Richard; BRANT, William E.; MAJOR, Nancy M. Fundamentals of 
body CT. Elsevier Health Sciences, 2006. 
 
• GAILLARD, F. Appendicolith; Radiopaedia. org. 2014. 
• William Herring. LEARNING RADIOLOGY, 2014 
 
• Mohammed Noeman, Gunnar Gaffke. KMG Klinikum Güstrow, Germany. (2012, 
Aug. 10) Le Fort III Fracture (Craniofacial Disjunction) {Online}