2. Abdominal trauma
Trauma causes I0% of deaths worldwide
The third commonest cause of death after malignancy
and vascular disease
3. Blunt abdominal trauma
Vehicular trauma (75%)
Blow to the abdomen (15%)
Fall from height (6-9%)
Others
Domestic accidents
Fights
Iatrogenic cardiopulmonary resuscitation
4. Mechanism of injury
Direct impact or
movement of organs
Compressive, stretching
or shearing forces
Solid Organs > Blood
Loss
Hollow Organs > Blood
Loss and Peritoneal
Contamination
Retroperitoneal >
Often asymptomatic
initially
6. Vectors of Force - Trauma
"Packages"
Right-sided Midline Left-sided
R hepatic
lobe
R kidney
Diaphragm
pancreatic
head
duodenum
IVC
Left hepatic
lobe
Pancreatic
body
Aorta
Transverse
colon
Duodenum
Small bowel
Spleen
L kidney
Diaphragm
Pancreatic
tail
10. Category B
Hemodynamically stable
Mild to moderate responsive hypotension
Significant trauma and have at least
moderate suspicion of intra-abdominal injury
based on clinical signs and symptoms
These patients should be evaluated by
imaging
11. Category C
Hemodynamically stable
Patients with hematuria after blunt
abdominal trauma
All patients with gross hematuria and
pelvic fracture require additional imaging
of the bladder to exclude bladder rupture
13. What is FAST?
A focused, goal directed, sonographic
examination of the abdomen
Goal is presence of haemoperitoneum or
haemopericardium
Can be integrated into the primary or
secondary survey and can be performed
quickly, without removing patients from the
clinical arena
Focused Assessment with Sonography for Trauma
14. What FAST is NOT
A definitive diagnostic investigation
A substitute for CT
15. The ABCDE of Trauma
A - Airway
B - Breathing
C - Circulation (FAST)
D - Disability
E - Environment and Exposure
16. The FAST examination
FAST examines four areas for free fluid:
Perihepatic & hepato-renal
space
Perisplenic
Pelvis
Pericardium
17. The perihepatic scan
The hepatorenal
space (pouch of
Morison)
most dependent
part of the upper
peritoneal cavity
The probe is placed
in the right mid- to
posterior axillary
line at the level of
the 12th ribs.
21. Perisplenic window
Transducer
positioned in left
posterior axillary line
between 10th and
11th ribs with beam
in coronal plane.
Demonstrates
spleen, kidney and
diaphragm
May be marred by
acoustic shadows
from ribs
May be improved by
imaging patient
whilst in full
inspiration.
23. The pelvic scan
The pelvic examination
visualises the cul-de-sac:
the Pouch of Douglas in
females and the
rectovesical pouch in the
male
Most dependent portion
of the lower abdomen
and pelvis, where fluid
will collect
The transducer is placed
midline just superior to
the symphysis pubis
24. The pericardial scan
For the subxiphoid view, the transducer-
probe should be placed in the subxiphoid
area and directed into the chest toward
the left shoulder so as to view the
diaphragm and heart. This view can be
difficult to obtain if the patient is
experiencing significant abdominal pain.
27. FAST: Strengths and Limitations
Strengths
Rapid (~2 mins)
Portable
Inexpensive
Technically simple,
easy to train
Can be performed
serially
Useful for guiding
triage decisions in
trauma patients
Limitations
Does not typically
identify source of
bleeding
Requires extensive
training to assess
parenchyma reliably
Limited in detecting
<250 cc
intraperitoneal fluid
Particularly poor at
detecting bowel and
mesentery damage
Difficult to assess
retroperitoneum
Limited by habitus
in obese patients
28. CT in Abdominal Trauma
Initial evaluation of
blunt trauma
penetrating trauma
Follow up of non-operative management
Rule out Injury
29. The findings to look for in abdominal trauma
are the following:
Hemoperitoneum
Pneumoperitoneum
Contrast blush consistent with active extravasation
Subcapsular hematomas
Laceration
Contusions
Devascularization of organs or parts of organs
30. Hemoperitoneum
Hyperdense intraperitoneal fluid collection
0–20HU Preexisting ascites
Bile
Urine
Digestive fluid
Diluted or old blood
30–45HU Free Unclotted
intraperitoneal blood
45–70HU Clotted blood/sentinel clot
sign hematoma
>100 HU Extravasation of contrast
medium
(vascular or urinary)
31. SENTINEL CLOT SIGN
• Clotted blood
adjacent to the site
of injury is of higher
attenuation value
than unclotted blood
which flows away .
• When the source of
intraperitoneal bleed
not evident, the
location of highest
attenuating blood
clot is a clue to the
most likely source
32. Spleen
The spleen is the most commonly
injured organ in blunt abdominal trauma
40% of all solid organ injuries
33. Plain film findings for spleen
trauma
left lower rib fracture
The classic triad indicative of acute
splenic rupture
Left hemidiaphragm
elevation
Left lower lobe atelectasis
Pleural effusion
37. Vascular Trauma
The most dangerous vascular traumatic
lesions are arterial lesions
Irregular area of increased density relative
to background spleen
Typically the attenuation value is within 10
HU of the adjacent artery
38. Delayed splenic rupture
Bleeding due to splenic injury occurring
more than 48 h after blunt trauma
following an apparently normal CT
examination
Due to ruptures of subcapsular splenic
haematomas.
39. Splenic CT Injury Grading Scale
Grade I Laceration(s) < 1 cm deep
Subcapsular hematoma < 1cm diameter
Grade
II
Laceration(s) 1-3 cm deep
Subcapsular or central hematoma l-3cm
diameter
Grade
III
Laceration(s) 3-10 cm deep
Subcapsular or central hematoma 3-10
cm diameter
Grade
IV
Laceration(s) > 10 cm deep
Subcapsular or central hematoma >
10cm diameter
Grade
V
Splenic tissue maceration or
devascularization
40. Simply :
Grade 1 is less than 1 cm.
Grade 2 is about 2 cm (1-3 cm).
Grade 3 is more than 3 cm.
Grade 4 is more than 10 cm.
Grade 5 is total devascularization or
maceration.
41. Contrast blush
A contrast blush is defined as an area of high density
with density measurements within 10 HU compared
to the nearby vessel (or aorta).
The differential diagnosis is:
Active arterial extravasation
Post-traumatic pseudoaneurysm
Post-traumatic AV fistula
42. Contrast-enhanced CT:
there is frank arterial
bleeding
from the splenic artery
associated with a
fragmented spleen.
Extensive
haemoperitoneum is
also present
43. SPLENIC INJURIES - Management
Grade I-III:Often arterial hemorrhage, therefore
nonoperative management less successful
Grade IV-V: almost invariably require operative
intervention
Delayed hemorrhage (hours to weeks post-injury):
8-21%
44. Liver
The liver is the second most commonly
injured organ in abdominal trauma.
Between 70 and 90% of hepatic injuries are
minor
Right lobe most commonly affected
45. Abdominal Trauma Protocol
Blunt injury -deceleration, crush, weapon (e.g.
bat)
venous phase ~70 secs
Delayed scan if injury present; ~3-5 mins
Penetrating injury: knives, gun
Same as blunt
Additional scan after rectal contrast material
46. Associated injuries:
2/3 have hemoperitoneum
45% have associated splenic injury
33% have rib fractures
Duodenal or pancreatic injury
Biliary injury: hematobilia, biloma, biliary
ascites, bile duct disruption
Ultrasound sensitive for grade 3 or
greater
47. Radiological overview of liver injury:
Right lobe> left lobe; 3:1
Posterior segment most common (fixed by
coronary ligament)
CT imaging method of choice
48. Features with impact on the
management and the prognosis
Number of segments involved by the lacerations
(significant if at least three segments are involved)
Central or subcapsular location of the lacerations
and contusions
Extension of lesions within the porta hepatis or the
gallbladder fossa
Importance of the hemoperitoneum
Vascular lesions with active bleeding or sentinel
clot sign
49. Green arrow: oval shaped hypodense area consistent with
hematoma
Yellow arrow: linear shaped hypodense area consistent
with laceration.
Notice that this laceration crosses the left portal vein
Blue arrow: vague ill defined hypodense area consistent
with contusion
Fluid around the liver
There is almost a transsection of the liver, but both lobes
do enhance so there is still normal vascular supply.
56. Periportal Edema
Periportal hypodensities running in parallel
to the portal branches
Causes
Diffusion from intraparenchymal bleeding
Dilatation of periportal lymph vessels
Vascular or focal bile duct dissection
60. Indications for surgical treatment in liver
trauma
Shock
Active venous bleeding
Trauma of the gallbladder
Abdominal surgery necessary for other causes
61. Retroperitoneal Hemorrhage
Retroperitoneal hemorrhage may arise from
injuries to major vascular structures, hollow
viscera, solid organs, or musculoskeletal structures
or a combination
65. Pancreas
Uncommon injury
1.1% incidence in penetrating trauma and only 0.2%
in blunt trauma.
Rarely an isolated injury.
Usually part of a 'package injury‘
Difficult to detect pancreatic injury on CT and one has
to rely on ancillary findings
Pancreatic duct injury cannot be directly visualized on
CT.
Deeper the laceration more likely that duct is injured
68. Indirect Signs
Edema with global pancreatic enlargement
and loss of lobulation
Peripancreatic fat infiltration
Peripancreatic fluid, especially if it is located
around the SMA or the omental bursa
Thickening of the left anterior pararenal
fascia or fluid in the anterior pararenal space
Concomitant duodenal injury
Hematic fluid between the dorsal surface of
pancreas- Considered a DIRECT SIGN
69. AAST GRADING OF PANCREAS INJURY
Grade
Type of
Injury Description of Injury
I Hematoma Minor contusion without duct injury
Laceration Superficial injury without duct injury
II Hematoma Major contusion without duct injury or
tissue loss
Laceration Major laceration without duct injury or
tissue loss
III Laceration Distal transection or parenchymal injury
with duct injury
IV Laceration Proximal transection or parenchymal
injury with probable duct injury (not
involving ampulla)
70. Imaging of Renal Trauma
Computed tomography (CT) is the modality of
choice in the evaluation of blunt renal injury
Injury to the kidney is seen in approximately 8%–
10% of patients with blunt or penetrating
abdominal injuries
71. Renal criteria for performing CT
in abdominal trauma
Macroscopic hematuria
Microscopic hematuria with shock
Important renal ecchymosis or fracture
of the lumbar transverse process
Open trauma involving the
retroperitoneum
Mechanism of deceleration (risk of
pedicle injury)
In children all types of posttraumatic
hematuria
72. Computed Tomography
Early and delayed CT scans through the kidneys
are necessary
Excretory-phase contrast (3min)
The preferred technique
Helical CT performed from the dome of the
diaphragm
Scanning parameters include
Collimation of 7 mm,
Pitch of 1.3,
Image reconstruction intervals of 7 mm.
74. Laceration
Hypodense, irregularly linear areas,
typically distributed along the vessels and
filled with blood.
They are best analyzed at arterial phase
Superficial (<1 cm from the renal cortex)
Deep (>1 cm from the renal cortex)
Renal medulla
Collecting tubule system
86. Urinoma/Urohematoma
Presence of a more or less significant
breach of the collecting tube system, with
urine escape reflected by extravasation of
contrast medium on delayed imaging, in an
extrarenal location
88. AAST organ injury severity scale grading system for
kidney injury
Grade 1 Contusion or contained and non -expanding
subcapsular haematoma, without parenchymal
laceration; haematuria
Grade 2 Non -expanding, confined, perirenal
haematoma or cortical laceration less than 1 cm
deep; no urinary extravasation
Grade 3 Parenchymal laceration extending more than 1
cm into cortex; no collecting system rupture or
urinary extravasation
Grade 4 Parenchymal laceration extending through the
renal cortex, medulla and collecting system
Grade 5 Pedicle injury or avulsion of renal hilum that
devascularizes the kidney; completely shattered
kidney;
89.
90. CT Cystography
Empty the bladder
Instill the contrast retrograde through the Foley
catheter of avg. 350-400 cc of contrast
Image the pelvis
BLADDER INJURY
92. Intraperitoneal rupture (type 2)
Cystography
Contrast in paracolic gutters, around bowel loops,
pouch of Douglas and intraperitoneal viscera
± Pelvic fracture
CT cystography
Contrast in paracolic gutters, around bowel loops,
pouch of Douglas and intraperitoneal viscera
97. Intestinal and Mesenteric
Traumas
Bowel or mesentery injury occurs in 5% of
patients with abdominal blunt trauma
More common following open trauma,
especially in injuries caused by firearms
98. Four CT findings should alert the
radiologist
1. Focal fat infiltration
2. Interloop hematoma (sentinel clot
sign)
3. Bowel wall thickening
4. Free intraperitoneal air
99. Small Bowel Injury
Diffuse circumferential thickening
Hypoperfused "shock" bowel
Focal thickening
Usually non-transmural injury
Specific findings, rare
Bowel content extravasation
Focal bowel wall discontinuity
Most common finding
Unexplained non-physiologic free fluid (84%)
Mesenteric stranding
Focal bowel thickening
Interloop fluid
If in combination, strongly suggestive
100. Indirect findings of traumatic
bowel perforation
Peritoneal findings
Sentinel clot
Focal mesenteric infiltration
GI findings
Pneumoperitoneal air bubbles localized within
the mesentery
Focal wall thickening
103. Causes of bowel thickening related to
trauma
Contusion/hematoma
Perforation
Distal ischemia due to mesenteric lesion
Bowel shock
Secondary to peritonitis
Bowel spasm
104. GI Ischemia
Bowel ischemia
Segmental (distal branch vessel injury)
Diffuse thickening of small bowel wall - hypotensive
shock bowel
Typical CT signs
Lack of parietal enhancement
Thickening of bowel wall
Parietal pneumatosis with presence of air inside the
bowel wall
Air in the mesentery and portal venous system
105. Role of Interventional Radiology
Embolization
Spleen
Liver
Pelvis
Angioplasty + Stent
Renal artery dissection
106. Agents for embolizations
Gelfoam
Soaked in an antibiotic solution
restorable
Can be cut in variable size
May result in too distal embolization
Risks for tissue infarction or late abscess
formation
Coils
Have variable size, length, diameter
Precise targeted delivery
Expensive
Need normal coagulation
Metal stents
Large-caliber patent artery
107. Advantages
Embolization can decrease the
amount of resuscitation fluid to
maintain vital sign.
Embolization can decrease shock
index
Operation with adjunct embolization
can decrease the mortality rate
Embolization is a promising way for
stopping bleeding
109. Role of MR Imaging in trauma
demonstrated to be a near-equivalent technique to
CT in the accurate appraisal of individual organ
injuries
The use of MRI at present confers no additional
advantages in the initial trauma evaluation
Limited access to patients for monitoring and
resuscitation and the need for MR-compatible
equipment pose major disadvantages.
At present MRI is reserved for problem solving
after the acute phase of trauma has passed
110. Take home messages:
Abdominal injuries are often underappreciated
radiologically either because of difficulty in
assessment caused by condition of patient or because
some signs take time to develop.
CT , mdct in particular has revolutionized the
management of trauma patient.
One should be aware of indirect signs of trauma on CT
Angiography has an increasing role in non operative
management of abdominal trauma