AJR 2001; 176:955-958
© American Roentgen Ray Society
The Spectrum of Abdominal Venous CT Findings in Blunt Trauma
John J. Hewett1,
Kelly S. Freed1,
Douglas H. Sheafor1,
Steven N. Vaslef2 and
Mark A. Kliewer1
1
Department of Radiology, Box 3808, Duke University Medical Center, Durham, NC
27710.
2
Department of Surgery, Duke University Medical Center, Durham, NC 27710.
Received January 4, 2000;
accepted after revision September 12, 2000.
Address correspondence to D. H. Sheafor.
Introduction
In the United States, abdominal CT is the primary imaging technique used to
examine patients who have sustained blunt abdominal trauma. At our
institution, imaging findings help direct patient treatment, particularly by
stratifying hemodynamically stable patients into those who require
intervention and those who can be treated nonsurgically. Vascular injury is an
especially important subset of traumatic injury because many patients with
this injury require urgent surgical or angiographic intervention and because
injuries—such as those to the retrohepatic inferior vena cava (IVC) and
the liver hilum—are associated with a high morbidity and mortality
[1]. In this article, we
present a spectrum of abdominal venous abnormalities from blunt trauma as
depicted on CT.
We searched the CT database at our level I trauma center for the abdominal
CT reports filed from 1988 to 1999 of patients who sustained blunt abdominal
trauma. Of approximately 25,000 reports of CT examinations, 735 reports
indicated possible venous abnormalities. These CT reports were examined for
representative cases of common venous injuries and of unusual vascular trauma.
Images from these CT studies were selected to show a range of abdominal venous
abnormalities, and findings were correlated with clinical, radiologic,
surgical, and pathologic records.
Abnormalities of the IVC
Slitlike IVC
In the setting of blunt abdominal trauma, a slitlike or collapsed IVC is an
important CT indicator of intravascular volume depletion and shock
(Fig. 1) and may be a sign of
hypovolemia from major hemorrhage
[2]. However, the collapsed IVC
must be seen at multiple levels to distinguish diminished venous pressure or
volume from the transient size fluctuations of the IVC that occur with
respiration and changes in intraabdominal pressure
[2].
View larger version (138K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 1. —36-year-old man injured in motor vehicle collision.
Contrast-enhanced CT scan shows collapsed inferior vena cava (arrow)
associated with severe hypotension. Extensive right renal laceration with
surrounding hematoma (H) is also present.
|
|
Contained Rupture of the IVC
Injuries to the IVC are relatively uncommon in the setting of blunt
abdominal trauma [3]. Signs of
caval injury include retroperitoneal hematoma surrounding the IVC, irregular
vessel contour, and extravasation. In the clinically stable trauma patient, CT
is a reliable tool for anatomic localization of IVC injury and assessment of
associated injuries. Patient survival is improved when the IVC hematoma is
contained [3,
4]
(Fig. 2).
View larger version (123K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 2. —24-year-old man injured in motorcycle collision.
Contrast-enhanced CT scan shows contained rupture (arrow) of
suprarenal inferior vena cava. Patient was treated nonsurgically and released
after 5 days without complication. (Reprinted from
[4])
|
|
Retrohepatic IVC Injury
Injury to the retrohepatic IVC is associated with a high rate of mortality,
exceeding 50% in most published series
[4]. It is crucial, therefore,
that the radiologist be able to recognize the signs of retrohepatic IVC injury
and communicate this possibility to the trauma surgeon. Interestingly, the
patient's clinical condition may seem paradoxically stable because the
surrounding liver can prevent extensive intraabdominal hemorrhage. Signs of
retrohepatic IVC injury on abdominal CT include liver laceration extending
into the porta hepatis and retrohepatic IVC and irregular contour of the
retrohepatic IVC (Fig. 3).
Recognition of a retrohepatic IVC injury can allow balloon tamponade of the
caval laceration to be performed by vascular radiologists before the patient
undergoes surgery [1,
3,
5,
6].
View larger version (144K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 3. —19-year-old woman injured in high-speed motor vehicle
collision. Contrast-enhanced CT scan shows large hepatic laceration extends to
involve retrohepatic inferior vena cava (arrow), which is surrounded
by low-density hematoma (arrowheads).
|
|
Fat in the IVC
The appearance of focal fat seen on CT in the retrohepatic IVC is most
frequently an artifact produced by the volume averaging of pericaval fat and
the vessel lumen [7] (Fig.
4A,4B).
Although rare, true herniation of fat through a caval laceration can be seen
in the setting of blunt abdominal trauma, particularly if significant hepatic
injury is present (Fig. 5).
Furthermore, fat embolism after major bone fracture can also lead to the
detection of fat attenuation within the IVC lumen
[4].
View larger version (72K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 4B. —Enhanced CT scans in 42-year-old man with no history of
trauma. Coronal reformatted image shows fat density (curved arrow)
actually lies adjacent to wall of inferior vena cava (straight
arrows).
|
|
View larger version (112K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 5. —32-year-old man crushed between cement truck and brick wall.
Contrast-enhanced CT scan shows avulsion of left hepatic lobe extends along
anatomic cleavage plane of falciform ligament, without enhancement of left
hepatic lobe (L). Intraluminal filling defect of fat attenuation in inferior
vena cava (arrow) can be seen. At exploratory laparotomy, herniation
of bowel loops into hepatic defect with fat extending into inferior vena caval
laceration was found. Patient died during surgery as result of pulmonary
embolism. (Reprinted from
[4])
|
|
Venous Abnormalities Related to the Liver
Portal and Hepatic Venous Injury
After the spleen, the liver is the second most commonly injured abdominal
organ. With the use of helical CT, the entire liver can be imaged near peak
contrast enhancement, which allows optimal visualization of the liver
parenchyma and vascular infrastructure. This allows accurate localization of a
hepatic laceration relative to the portal and hepatic veins. Lacerations
involving small hepatic vessels can tamponade spontaneously, unlike
lacerations involving larger vessels, especially those near the liver hilum,
which are less likely to be contained.
Signs of vascular injury include a hepatic laceration extending to or
through a hepatic or portal vein (Fig.
6), vessel contour irregularity, or the abrupt cutoff of a hepatic
or portal vein (Fig.
7A,7B).
Active contrast material extravasation is the most direct and dramatic
evidence of vascular injury, originating most commonly from an arterial
source. Active bleeding (Fig.
8) usually presents as an ill-defined high-attenuation collection
with attenuation values that are greater than or equal to those of the
adjacent enhanced vasculature
[2].
View larger version (145K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 6. —39-year-old woman injured in motor vehicle collision.
Contrast-enhanced CT scan shows extensive hepatic laceration (arrows)
involving right portal vein (arrowhead). Surgical repair was
required.
|
|
View larger version (155K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 7A. —18-year-old woman who was restrained passenger in motor
vehicle collision. Contrast-enhanced CT scan reveals parenchymal injury to
right lobe of liver. Note attenuation of right hepatic vein (arrow),
hemoperitoneum (H), and extensive liver laceration. Injuries to right hepatic
and portal veins were discovered at surgery.
|
|
View larger version (167K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 7B. —18-year-old woman who was restrained passenger in motor
vehicle collision. Contrast-enhanced CT scan shows abrupt termination of right
portal vein (arrow) at site of injury. Lack of enhancement of right
hepatic lobe is presumably because of portal venous injury.
|
|
View larger version (123K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 8. —3-year-old boy who was run over by a tractor.
Contrast-enhanced CT scan reveals large hepatic laceration extending to porta
hepatis and retrohepatic inferior vena cava with irregular high attenuation
(arrow) indicating active extravasation. Surgical exploration
revealed laceration of middle hepatic vein.
|
|
Although many hepatic injuries can be managed nonsurgically with close
clinical observation, lacerations involving major vascular structures are
usually treated surgically
[7].
Periportal Radiolucency
In the absence of hepatic injury, periportal radiolucency is most likely
the result of rapid expansion of intravascular volume by vigorous hydration,
which leads to the engorgement of periportal lymphatics and lymphedema
[2]
(Fig. 9). True hemorrhage is
unlikely to cause diffuse periportal radiolucency but may present as focal
periportal low attenuation adjacent to an area of hepatic injury (Fig.
10A,10B).
In hemodynamically stable patients, generalized periportal radiolucency can be
dismissed as insignificant [2],
whereas focal periportal radiolucency suggests hemorrhage potentially caused
by an occult hepatic laceration
[5].
View larger version (114K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 9. —17-year-old girl injured in motor vehicle collision.
Contrast-enhanced CT scan shows diffuse periportal low attenuation
(arrows) that was likely caused by intravascular volume expansion
because no other evidence of liver injury was seen at CT. Patient recovered
after nonsurgical treatment.
|
|
View larger version (148K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 10A. —27-year-old man injured in motor vehicle collision.
Contrast-enhanced CT scan shows focal periportal low attenuation (curved
arrow) adjacent to hepatic laceration (straight arrow). Surgery
revealed middle hepatic vein laceration.
|
|
View larger version (174K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 10B. —27-year-old man injured in motor vehicle collision.
Contrast-enhanced CT scan at more caudal location than A shows
laceration (straight arrow) with normal appearance of posterior
branch of right portal vein (open arrow).
|
|
Mesenteric Venous Abnormalities
Bowel and mesenteric injuries are found in approximately 5% of all patients
who undergo laparotomy after blunt abdominal trauma
[1]. The physical examination
in patients with these injuries is often unrevealing, and symptoms are often
nonspecific or develop several hours from the time of injury. However, early
recognition of bowel and mesenteric injuries is vital because diagnostic
delays can result in patient mortality rates approaching 60%
[3].
Localized hematoma with mesenteric infiltration (Figs.
11 and
12) is the CT hallmark of
mesenteric injury and is seen in approximately 90% of the patients with
vascular disruption [5].
Mesenteric injuries often involve both arterial and venous disruptions.
Visualization of the sentinel clot sign, or a localized higher attenuation
hematoma, may be useful in identifying the source of hemorrhage in the setting
of diffuse hemoperitoneum. In 40% of the cases of mesenteric injuries,
solid-organ and mesenteric injuries occur concurrently
[1,
8], However, even in the
setting of solid-organ injury, high-density hematoma adjacent to bowel is
suggestive of subtle bowel or mesenteric injury and may be an indication for
exploratory laparotomy [8].
View larger version (123K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 11. —61-year-old male pedestrian who was struck by car.
Contrast-enhanced CT scan shows swirling high-density material
(arrow), which is compatible with active hemorrhage and is likely
from arterial injury. Surgical exploration revealed small-bowel mesenteric
avulsion with venous and arterial damage.
|
|
View larger version (159K):
[in this window]
[in a new window]
[as a PowerPoint slide]
|
Fig. 12. —37-year-old female pedestrian who was struck by car.
Contrast-enhanced CT scan shows large mesenteric hematoma (H). High-density
material centrally represents active hemorrhage that is likely from both
arterial and venous sources. Narrowed lumen (arrow) with surrounding
hematoma can be seen. Surgery revealed avulsion of superior mesenteric
vein.
|
|
References
-
Raptopoulos V. Abdominal trauma: emphasis on computed tomography.
Radiol Clin North Am
1994;32:969
-987[Medline]
-
Shanmuganathan K, Mirvis SE, Amoroso M. Periportal low density on
CT in patients with blunt trauma: association with elevated venous pressure.
AJR
1993;160:279
-283[Abstract/Free Full Text]
-
Ombrellare MP, Freeman MB, Stevens SL, Diamond DL, Goldman MH.
Predictors of survival after inferior vena cava injuries. Am
Surg 1997;63:178
-183[Medline]
-
Sheafor DH, Foti TM, Vaslef SN, Nelson RC. Fat in the inferior vena
cava associated with caval injury. AJR
1998;171:181
-182[Free Full Text]
-
Wolfman NT, Bechtold RE, Scharling ES, Meredith JW. Blunt upper
abdominal trauma: evaluation by CT. AJR
1992;158:493
-501[Abstract/Free Full Text]
-
Jeffrey RB Jr, Olcott EW. Imaging of blunt hepatic trauma.
Radiol Clin North Am
1991;29:1299
-1310[Medline]
-
Cunningham MA, Tyroch AH, Kaups KL, Davis JW. Does free fluid on
abdominal computed tomographic scan after blunt trauma require laparotomy?
J Trauma Infect Crit Care
1998;44:599
-603
-
Rizzo MJ, Federle MP, Griffiths BG. Bowel and mesenteric injury
following blunt abdominal trauma: evaluation with CT.
Radiology
1989;173:143
-148[Abstract/Free Full Text]
CiteULike 
Complore 
Connotea 
Del.icio.us 
Digg 
Reddit 
Technorati What's this?
Top
Introduction
Abnormalities of the IVC
