TRAUMA CT Karl Johnson

BIRMINGHAM CHILDREN’S HOSPITAL

U.K.

SINGLE PAEDIATRIC MAJOR TRAUMA CENTRE SERVING POPULTION OF ~ 6 MIILION PEOPLECONCENTRATION OF SERVICES AND EXPERTISE TO IMPROVE OUTCOMES

Overview

• WHY CT ?

• INDICATIONS

• IMAGING PROTOCOLS

• TECHNIQUE

• IMAGING FINDINGS AND CLINICAL IMPLICATIONS

Basic standard of care

• If suspected significant intracranial, vertebral (skeletal) or visceral injury as a result of trauma (blunt or penetrating) then CT is the imaging method of choice

• CT is the most sensitive and specific investigation in the acute situation

• Quick - allows ongoing patient resuscitation

• Rapid triage of the child to help determine patient management

• Road map for interventional radiology

• In significant (major) trauma with potential life altering /limiting injuries CT should be performed and reported within 1 hour of hospital admission

Paediatric Trauma

• Head injury major cause of death.

• Most seriously injured children have multiple injuries-predictor of head injury.

• Paediatric trauma deaths have a trimodal distribution • ~ 50% dying at the scene from either severe head injury or major

haemorrhage. • ~ A further 30% die within the first few hours from head injury, haemorrhage,

or airway emergencies.• Late deaths due to organ failure and sepsis are often due to inadequate initial

resuscitation.

• Up to 30% of deaths are preventable by rapid identification of problems and early aggressive treatment.

?

• Each child and clinical situation is unique.

• Prior to imaging there should be a Senior Clinical Discussion about what body areas (head, neck, chest, abdomen, pelvis) needs to be scanned and the indications.

• Allows rational thought and justification.

• While a Whole Body CT (WBCT) may be performed; it is important each area is justified.

• WBCT should not be regarded as the default standard test.

• Special consideration must be given to patients who have been exposed to higher energy mechanisms of injury who have clearly suffered severe injury to more than one body region, especially where there are signs of shock.

• Clinical examination can be misleading where a distracting injury is present or impossible in the context of severe brain injury.

• Although WBCT should not be considered a routine investigation in injured children, it is an investigation that is currently used in selected cases by clinicians who have carefully considered the overall risks and benefits.

• This should be considered when discussing imaging strategy with colleagues from other specialties.

• Image appropriate areas only.

• Acceptable noise (reduction in kV and mA).

• Dose modulation and iterative reconstruction -but need to avoid delay.

• Single dual phase imaging.

• In the rare cases where delayed imaging is required then should over a limited area.

Indications

British bias.

Lots of guidelines and protocols have been published –varying levels of evidence base.

Important that both radiologists and clinicians agree.

Pragmatic rather then dogmatic.

Review and audit are essential.

Head

• Post traumatic seizure.

• Focal neurological deficit.

• Persistent headache.

• Vomiting >3.

• Initial assessment (at the scene) Glasgow coma score(GCS) <14 or under 1 <15.

• <15 at 2 hrs.

• Suspected skull injury (depressed, base of skull-hemotympanum , panda eyes, CSF leak, tense fontanelle.

Cervical spineIn Children who present in with Head injury

• Risk factors of cervical spine injury• GCS<13• Neurological symptoms• Focal peripheral neurology• Parathesia• Neck pain• Tenderness

• Distracting injury.• Altered alertness/mental status/intoxication.• If surgery contemplated.

Pragmatic

• Plain film – if done well can exclude cervical spine fracture

• Repeat radiographs increasing dose

• But if child in collar quality is often poor

• Time consuming

• CT quick efficient, greater diagnostic confidence

• Multiplanar

CHEST

• Primary investigation is a chest x-rayCT may be obviated IF

• CXR normal

• Patient is conscious

• Clinically stable

• Consideration also of child’s age, mechanism, possible vertebral injury

• If penetrating injury -need CT

Abdomen/Pelvis

• Pain, • Abdominal distension• Guarding/rigidity • Absent bowel sounds • Soft tissue injury/bruising• lap belt ecchymosis handlebar • Hypotension• Blood from the rectum or nasogastric tube.• Tachycardia • ^ WBC • Delayed presentation in >10%

BLUNT TRAUMA

Penetrating trauma

• Guidelines based on blunt trauma

• Penetrating injury becoming more common in teenagers

• Reduced threshold for increased coverage

• Unaware of internal trajectory

TECHNIQUE• Head (and neck) typically non-

contrast- (unless carotid arteries, penetrating injury)

• Chest arterial phase

• Abdomen - Dual contrast study -allows both arterial and porto/venous imaging of the abdomen

• Contrast -2ml/kg -300mg/ml Iodine• Injection over ~70secs- rate varies by

weight

• - 2/3 volume injected at a slow rate

• -1/3 volume injected ~ 2-3 times quicker

Reporting proforma

• Checklist Form

• Covers each area

• Yes /No responses about the presence or absence of radiological features

• Helps radiologist provide quick overview

• Helps direct acute management

• Not a substitute for formal report

IMAGING- a brief review

• HEAD

• SPINE

• CHEST

• ABDOMEN

• PELVIS

• View in all 3 planes using multiple window levels

Head

Traumatic brain injury is responsible for >75% of deaths in paediatric trauma victims

Primary CT to detect surgical correctable pathology

Determine need for intracranial pressure monitoring

Acceleration/deceleration mechanism often associated with diffuse axonal injury

Oedema

Petechial haemorrhage

Signs of hypoxic ischemic injury within first few hours suggests a poorer prognosis

‘Reversal sign’ relatively high attenuation of the cerebellum due to a generalized decrease in density of the supratentorial brain structures caused by extensive oedema

Initial CT may be normal –but does not exclude intracranial pathology

Spine

• CT will only exclude vertebral fractures

• Will not ‘clear’ the C spine

• Can understate the extent of injury

• No assessment of ligament injury or spinal cord injury

• Findings need to be put into clinical context

MRI

• Challenging in the intubated and unstable patient

• MRI will assess spinal cored and epidural space

• Will often detect marrow oedema beyond recognized fractures

CHEST

• CXR often sufficient

• Children with lung injuries typically suffer multisystem trauma

• Findings• Pneumothorax• Rib fractures • Contusions• Lacerations • Aorta and Bronchial

injury- rare

• Contusions • air space shadowing

• Peripheral sparing

• 4-6 hrs. after trauma

• Lacerations• Air filled cyst,

• fluid/fluid levels

• Implies greater trauma

• Associated with longer ITU stay

Aorta• Aortic injury is rare in children

• Greater chest compliance

• Elastic vascular tissue

• Less body mass

• Seat belts

• Major cause of mortality

• Rapid deceleration

• Fixation aorta at ligamentum arteriosum

•Findings in Aortic Injury

• Periaortic Haematoma

• Pseudoaneurysm

• Loss of normal internal margina

• Change in aortic contour- loss of continuity

• Extravasation of contrast

• Periaortic Haematoma• Easiest sign to detect

• Absent in 20%

• Pseudo aneurysm• Abnormal aortic outline

• Change in contour

• Filling defect and loss of normal internal contours• Haematoma

• Thrombus

• dissection

• Change in aortic contour-loss of continuity

• Extravasation contrast

Abdomen

• Bowel and visceral injuries

• Blunt trauma, the result of deceleration/ shearing or direct impact

• Typically managed conservatively• Unless uncontrolled hemorrhage

• Bowel injury/perforation

• Visceral injury various grading system – manage the patient

• Grading can act as a Predictor of complications

Hypoperfusion complex The Shocked Child

Compensated –Decompensated -Irreversible

• Causes• Severe haemorrhage

• Neurogenic shock

• Cardiac arrest

• Poor prognosis in trauma patients (85% mortality rate)

• Child good at compensating and CT findings may precede clinical arrest

• Bowel wall thickening and paradoxical enhancement (damage vascular endothelium)

• Liver heterogenous with periportal oedema

• Thickened and enhancement renal cortex

• Flattened IVC

• Feathery hyperintense pancreas

• Gall bladder enhancement

• Adrenal enhancement

BOWEL INJURY• May be overlooked on initial review

• Blunt trauma • Compressions on of intestinal loops, increased intraluminal pressure

• Crush injury

• Poor fitting seat belts –higher center of gravity In children lead to hyperflexion

• Jejunum/ileum 45%, Duodenum 27%, Colon 37%, Stomach 10%

•Findings in bowel trauma

• Mesenteric haematoma

• Bowel wall thickening

• Abnormal enhancement

• Free intraperitoneal air

• Extravasated bowel content

• Peritoneal fluid• Non specific –

• consider bowel injury in absence solid organ injury/pelvic fracture

• Bowel wall thickening• >3mm

• Intramural haematoma

• May be localised

• Abnormal enhancement • Psoas as reference• increase seen in hypoperfusion due

to damaged vascular endothelium• Decreased - focal contusion or

mesenteric vascular injury

• Mesenteric haematoma • Often mesenteric root(>70 HU)

• Stranding in the mesentery

• Collections may develop

Duodenal trauma

• Haematoma (non enhancing) intramural, intraluminal or Para duodenal

• Follows contours of the duodenum

• Free /retroperitoneal air • Angular and curvilinear

• Anterior abdominal wall and liver

• Small foci gas

• Lung windows helpful

Hepatic trauma

• AAST injury scale grade I-VI

• Laceration irregular branching low attenuation foci that does not enhance

• Subcapsular collections

• Involvement of porta hepatis or major more likely to result in complications- biliary leak and pseudoaneurysm

And the spleen

Renal

• Contusions• Reduced enhancement

• Lacerations• Defect of renal surface • Low attenuation • Associated with hematomas, vascular

injury and thrombosis and urine leaks

• Haematomas • Fluid attenuation collection• Can displace bowel/kidney

• Collecting system laceration/injury • Urine mixed with haematoma

• Extravasation of contrast

• Delayed imaging

• May require stenting

Pancreas

• Laceration in pancreas

• Fracture extends from one capsular surface to the other

• Rupture multiple fragments

• Peripancreatic haematoma

• Check for venous thrombus

Pelvis• Rare but due to high impact and

often concomitant injuries.• Immature skeleton more elastic/

thicker periosteum• If triradiate cartilage is open pelvis

is regarded as immature

• Various classification systems define stability.

• Check integrity SIJs• Vertical instability and rotational

deformity.• Operative indications –

instability, severe displacement and articular involvement

CT in Paediatric trauma

• The Gold standard

• Appropriate use based on senior clinical discussion

• Allows fast and sensitive diagnosis improving outcomes

• Able to plan future management

THANK YOU

KIITOS