DOI:10.2214/AJR.05.0946
AJR 2006; 187:658-666
© American Roentgen Ray Society
Appearance of Solid Organ Injury with Contrast-Enhanced Sonography in Blunt Abdominal Trauma: Preliminary Experience
John P. McGahan1,
Stephanie Horton1,
Eugenio O. Gerscovich1,
Marijo Gillen1,
John R. Richards2,
Michael S. Cronan1,
John M. Brock1,
Felix Battistella3,
David H. Wisner3 and
James F. Holmes2
1 Department of Radiology, University of California, Davis School of Medicine,
UC Davis Medical Center, 4860 Y St., Ste. 3100, Sacramento, CA 95817.
2 Department of Emergency Medicine, University of California, Davis School of
Medicine, UC Davis Medical Center, Sacramento, CA 95817.
3 Department of Surgery, University of California, Davis School of Medicine, UC
Davis Medical Center, Sacramento, CA 95817.
Received June 3, 2005;
accepted after revision July 22, 2005.
Supported by an internally funded grant from the Department of Radiology,
University of California, Davis. Address correspondence to J. P. McGahan
(john.mcgahan{at}ucdmc.ucdavis.edu).
Abstract
OBJECTIVE. The purpose of this study was to compare the detection
rate of injury and characterize imaging findings of contrast-enhanced
sonography and non-contrast-enhanced sonography in the setting of confirmed
solid organ injury.
SUBJECTS AND METHODS. This prospective study involved identifying
hepatic, splenic, and renal injuries on contrast-enhanced CT. After injury
identification, both non-contrast-enhanced sonography and contrast-enhanced
sonography were performed to identify the possible injury and to analyze the
appearance of the injury. The sonographic appearance of hepatic, splenic, and
renal injuries was then analyzed, and the conspicuity of the injuries was
graded on a scale from 0 (nonvisualization) to 3 (high visualization).
RESULTS. Non-contrast-enhanced sonography revealed 11 (50%) of 22
injuries, whereas contrast-enhanced sonography depicted 20 (91%) of 22
injuries. The average grade for conspicuity of injuries was increased from
0.67 to 2.33 for spleen injuries and from 1.0 to 2.2 for liver injuries
comparing non-contrast-enhanced with contrast-enhanced sonography,
respectively, on a scale from 0, being nonvisualization, to 3, being high
visualization. The splenic injuries appeared hypoechoic with occasional areas
of normal enhancing splenic tissue within the laceration with
contrast-enhanced sonography. Different patterns were observed in liver
injuries including a central hypoechoic region. In some liver injuries there
was a surrounding hyperechoic region.
CONCLUSION. Contrast-enhanced sonography greatly enhances
visualization of liver and spleen injuries compared with non-contrast-enhanced
sonography. Solid organ injuries usually appeared hypoechoic on
contrast-enhanced sonography, but often a hyperechoic region surrounding the
injury also was identified with liver injuries.
Keywords: abdominal imaging contrast media sonography trauma
Introduction
The main focus of sonography for the patient with blunt abdominal trauma is
the detection of free fluid. In one original report, this sonographic
examination consisted of only a single view of Morison's pouch to detect free
fluid [1]. However, during its
evolution over the past three decades, sonography for blunt abdominal trauma
has become more standardized and is now termed "focused abdominal
sonography for trauma" (FAST)
[2]. Early studies showed the
sensitivity of sonography, using detection of free fluid alone, to be in the
range of 90%, with specificities of from 97% to 100%
[3-6].
Although FAST is primarily used for the detection of free fluid in the abdomen
or pelvis, there have been studies showing the ability to detect parenchymal
organ injury [6,
7]. Although most researchers
have either ignored detection of solid organ injury or reported a low
detection rate [1], there have
been studies in which detection of solid organ injury with FAST was 41%
[6,
7]. A limitation of sonography
using only free fluid as the sole criterion of injury is that parenchymal
injuries requiring surgery or embolization may be present without free fluid
[8-11].
More recently, several authors have reported an increased detection rate of
solid organ injury in patients with blunt abdominal trauma using
contrast-enhanced sonography
[12-14].
In this study, we present our preliminary data using contrast-enhanced
sonography to detect solid organ injury in patients with blunt abdominal
trauma and compare contrast-enhanced sonography and non-contrast-enhanced
sonography with CT.
Subjects and Methods
This prospective study was conducted from June 2004 through March of 2005
and was approved by our institutional review board. Written informed consent
was obtained from all patients. Subjects considered for inclusion were 18
years old or older who had an injury of the liver, spleen, or kidney detected
on CT and were not candidates for immediate surgery. All patients underwent
dedicated contrast-enhanced CT (LightSpeed 16, GE Healthcare) of the abdomen
and pelvis with IV contrast material (120-150 mL of iohexol [Omnipaque 300,
Amersham Health]) injected at 2.5 mL/s. No oral contrast material was
administered. The technique used an automatic milliamperage setting from 200
to 440 mA at 120 kV. Detector collimation was 1.25 mm, and scans were
reconstructed at 5 mm every 5 mm. A 5-minute delayed scan of the upper abdomen
was obtained using a similar technique.
Organ injuries detected on CT were graded using a scale developed by the
American Association for the Surgery of Trauma for splenic, hepatic, and renal
injuries
[15-17].
A modified and abbreviated version of this scale created by the Organ Injury
Scaling Committee of the American Association for the Surgery of Trauma for
liver and spleen injuries is presented in Tables
1 and
2; for a more complete table
and CT modification of the tables, the reader is referred to references
15 through
17.
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TABLE 1: American Association for the Surgery of Trauma (AAST) Scale and Modified
Scale for Classification of Liver Injuries
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TABLE 2: American Association for the Surgery of Trauma (AAST) Scale and Modified
Scale for Classification of Liver Injuries
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Radiology faculty interpreting the CT examinations notified the clinical
coordinator when a patient had a solid organ injury detected on CT. The
clinical coordinator was blinded to the site of injury. A different radiology
faculty membernot involved in interpreting the CT examination and
blinded to the site of the injurywas notified to obtain informed
consent. Baseline sonography followed by contrast-enhanced sonography was then
performed. All sonographic examinations were performed by the same sonographer
who had more than 2 years of experience with contrast-enhanced sonography. The
radiologist who had obtained informed consent was present for the sonographic
examinations. Sonography was always performed within 48 hours after the CT
examination.
All sonography examinations were performed on a Sequoia unit
(Siemens-Acuson); baseline scan images of the right upper quadrant, left upper
quadrant, mid epigastrium, right flank, left flank, and pelvis were obtained
using a 4-MHz convex transducer. Tissue harmonics were used with a 4-MHz
convex transducer using a low mechanical index of 0.3-0.6 for the
contrast-enhanced sonography portion of the examination. For contrast
enhancement, a 0.1-mL dose of SH U 508A (Definity, Bristol-Myers Squibb) was
injected within 30 seconds into an antecubital vein followed by a 10-mL saline
flush. Immediately after contrast injection, the right upper quadrant of the
abdomen was scanned for 3-4 minutes until the enhancement effect began to
subside. Then another 0.1-mL dose of SH U 508A was injected, followed by
imaging of the left upper quadrant of the abdomen for 3-4 minutes. In four
patients, 0.2-mL of SH U 508A was injected at one site because of inadequate
contrast response in the organ of interest. All injections were performed by
one individual. All video and still images were recorded for review on a
workstation (Kinetics, Siemens-Acuson). Only selected 2-second video clips of
the examinations, including at least arterial, venous, and delayed images,
were obtained. Injections were separated by a time interval of approximately
5-7 minutes. The total time for the examination was approximately 15 minutes;
the SD of the time needed for each examination was not calculated.
A data sheet was completed by both radiologists noting the presence or
absence of injury and, if present, the extent of solid organ injury shown on
CT, non-contrast-enhanced sonography, and contrast-enhanced sonography. The
presence or absence of free fluid detected using CT, non-contrast-enhanced
sonography, and contrast-enhanced sonography was noted by both radiologists.
The injury was graded based on its conspicuity from 0 to 3 for
non-contrast-enhanced sonography, contrast-enhanced sonography, and CT. The
scale used was adapted from Catalano et al.
[14], where 0 = not
recognizable; 1 = low injury-to-parenchyma gradient; 2 = medium
injury-to-parenchyma gradient; and 3 = high injury-to-parenchyma gradient.
Thus for grade 0, the echogenicity of the suspected region of injury and the
echogenicity of the noninjured parenchyma were nearly equal and the injury was
not seen. In grade 3 injuries, the echogenicity of the region of injury was
very different from the echogenicity of the noninjured parenchyma and the
region of injury was easily identified. Grade 1 and grade 2 injuries were
intermediate in conspicuity on this scale. Grade 1 injuries were seen but were
not as easily identified as grade 2 injuries. The sonographic appearance of
these injuries was described as hypoechoic, isoechoic, or hyperechoic.

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Fig. 1B Splenic laceration with subcapsular hematoma in 46-year-old
woman. Longitudinal non-contrast-enhanced sonogram shows central heterogeneous
region (arrow) with normal-appearing spleen posteriorly and
subcapsular hematoma anteriorly.
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Fig. 1C Splenic laceration with subcapsular hematoma in 46-year-old
woman. Longitudinal contrast-enhanced sonogram shows that splenic tissue noted
posteriorly appears perfused and echogenic. Central region (arrow),
which is nonperfused, is more hypoechoic and corresponds to region of splenic
laceration. More anterior hypoechoic region corresponding to subcapsular
hematoma remains hypoechoic.
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Results
The results for CT, non-contrast-enhanced sonography, and contrast-enhanced
sonography are reported in Table
3. CT depicted free fluid in 10 of 20 patients. There was no
difference in the detection of free fluid between non-contrast-enhanced
sonography and contrast-enhanced sonography; both showed free fluid in the
same 10 of 20 patients as revealed on CT. Eleven subcapsular hematomas of the
liver or spleen were identified on CT. Only four (36%) were seen on
non-contrast-enhanced sonography, whereas all 11 (100%) were seen on
contrast-enhanced sonography (Figs.
1A,
1B, and
1C). There were no
false-positive non-contrast-enhanced sonography or contrast-enhanced
sonography examinations.
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TABLE 3: Visualization of Subcapsular Hematomas and Organ Injuries on
Contrast-Enhanced CT, NonContrast-Enhanced Sonography, and
Contrast-Enhanced Sonography
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Twenty-two solid organ injuries were detected in 20 patients on CT.
Non-contrast-enhanced sonography showed 11 (50%) of the 22 injuries, whereas
contrast-enhanced sonography showed 20 (91%) of the 22 injuries.
Classification of hepatic and splenic injuries and the number of each type are
presented in Tables 4 and
5. The only liver injury not
visualized on contrast-enhanced sonography during prospective review was a
2.5-cm laceration in the left lobe. However, during retrospective review of
the video record, this laceration could be identified as a linear hypoechoic
region. The conspicuity scale breakdown for the spleen and liver injuries is
presented in Tables 6 and
7. The average conspicuity
grade for the splenic injuries increased from 0.67 for non-contrast-enhanced
sonography to 2.33 for contrast-enhanced sonography. With regard to liver
injuries, the conspicuity scale increased from 1.0 for non-contrast-enhanced
sonography to 2.2 for contrast-enhanced sonography. Injuries that were not
identified on either non-contrast-enhanced sonography or contrast-enhanced
sonography were given a score of 0.
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TABLE 4: Splenic Injury Severity Compared with Detection Rate on
NonContrast-Enhanced Sonography and Contrast-Enhanced
Sonography
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TABLE 5: Liver Injury Severity Compared with Detection Rate on
NonContrast-Enhanced Sonography and Contrast-Enhanced
Sonography
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TABLE 6: Spleen Injuries: Comparison of Conspicuity on CT, NonContrast
Enhanced Sonography, and Contrast-Enhanced Sonography
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TABLE 7: Liver Injuries: Comparison of Conspicuity on CT, NonContrast
Enhanced Sonography, and Contrast-Enhanced Sonography
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There were three renal injuries in which only a renal laceration with a
subcapsular hematoma was seen on non-contrast-enhanced sonography. These
injuries were better seen with contrast-enhanced sonography. An avulsed kidney
was not seen on non-contrast-enhanced sonography, whereas it was identified on
contrast-enhanced sonography. A renal laceration was not seen with
contrast-enhanced sonography.
The echogenicity of liver and spleen injuries before and after contrast
administration was of particular interest. Splenic injuries were most often
hypoechoic when visualized on non-contrast-enhanced sonography (Figs.
1A,
1B, and
1C). Three of four injuries
seen on non-contrast-enhanced sonography were hypoechoic compared with the
surrounding parenchyma. On contrast-enhanced sonography, these injuries
appeared more conspicuous and hypoechoic against the surrounding enhanced
splenic parenchyma. All injuries identified on contrast-enhanced sonography
were hypoechoic compared with surrounding parenchyma (Figs.
1A,
1B,
1C,
2A, and
2B). Areas of enhancement of
the splenic parenchyma could be observed within stellate splenic lacerations
and were similar to the appearance on CT (Figs.
3A and
3B). The avascular regions
appeared hypoechoic and devoid of contrast microbubbles on contrast-enhanced
sonography, whereas microbubbles could be seen in the surrounding parenchyma.
Unfortunately, in our imaging studies, the transaxial CT plane could not be
reproduced exactly with sonography because of overlying ribs.

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Fig. 2B Splenic laceration in 20-year-old woman.
Non-contrast-enhanced sonogram was interpreted as showing normal findings,
whereas this axial contrast-enhanced sonogram shows well-demarcated hypoechoic
splenic laceration (arrow), which correlated with appearance on
contrast-enhanced CT.
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Fig. 3B Splenic laceration in 23-year-old woman. Based on
longitudinal non-contrast-enhanced sonogram (not shown), spleen was
interpreted as normal; however, this axial contrast-enhanced sonogram shows
splenic laceration corresponding to region on CT with areas within laceration
that were perfused splenic tissue (arrow).
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In most patients with liver injuries, there was correlation between CT,
non-contrast-enhanced sonography, and contrast-enhanced sonography. Most
commonly a hypodense region within the liver detected on CT corresponded to a
heterogeneous hyperechoic region on non-contrast-enhanced sonography. In four
of six cases in which injury was seen on non-contrast-enhanced sonography, the
appearance of the liver injury compared with surrounding parenchyma was
hyperechoic. One injury was hypoechoic on non-contrast-enhanced sonography,
whereas another injury was hyperechoic with a central hypoechoic region on
non-contrast-enhanced sonography. This was then followed by contrast-enhanced
sonography showing a hypoechoic region in six cases (Figs.
4A,
4B, and
4C). However, a different
pattern was identified in some liver injuries. In these cases, the hyperechoic
region of injury detected on non-contrast-enhanced sonography was also
identified on contrast-enhanced sonography. The periphery of this hyperechoic
region appeared to enhance on contrast-enhanced sonography in three cases
(Figs. 5A,
5B,
5C,
6A,
6B,
6C, and
6D). However, within the
center of the hyperechoic region, a linear hypoechoic region was identified
using contrast-enhanced sonography in three cases (Figs.
5A,
5B,
5C,
6A,
6B,
6C, and
6D).

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Fig. 4C Liver laceration in 46-year-old woman. Axial
contrast-enhanced sonogram shows central hypoechoic region (straight
arrow). Hypoechoic region was surrounded by perfused hyperechoic region
(curved arrow).
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Fig. 5B Liver laceration in 21-year-old woman. Longitudinal
non-contrast-enhanced sonogram of liver shows fairly large echogenic region of
liver (arrow) that corresponds to site of injury identified on
CT.
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Fig. 5C Liver laceration in 21-year-old woman. Longitudinal
contrast-enhanced sonogram shows echogenic region (arrowhead) to be
perfused and to appear slightly more echogenic than normal liver. However,
there was nonperfused central hypoechoic region (curved arrow). Also
note hematoma in hepatorenal fossa (straight arrow) that was not
identified on initial non-contrast-enhanced sonogram.
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Fig. 6B Liver laceration in 32-year-old man. Longitudinal
non-contrast-enhanced sonogram shows large heterogeneous hyperechoic region
(arrow) noted in liver in corresponding area of injury identified on
CT.
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Fig. 6C Liver laceration in 32-year-old man. Contrast-enhanced
sonogram shows that some of peripheral region that appeared hyperechoic on
non-contrast-enhanced sonogram is perfused (arrowhead). However, more
centrally, there is hypoechoic region (arrow) that corresponds to
region of liver laceration, hematoma, or both.
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For some of these injuries, there were minor discrepancies between the size
of the injury on non-contrast-enhanced sonography, contrast-enhanced
sonography, and CT. An example of this discrepancy is shown in Figures
5A,
5B, and
5C in which a presumed large
liver laceration is detected on CT. Non-contrast-enhanced sonography shows an
echogenic area roughly corresponding to the CT finding. However,
contrast-enhanced sonography depicts a smaller hypoechoic region centrally
surrounded by an isoechoic to hyperechoic region that appeared to enhance on
contrast-enhanced sonography.
Discussion
Initial reports about the use of sonography in patients with blunt
abdominal trauma concentrated on detection of free fluid in the abdomen, and
in many early studies, there were very high sensitivity rates for this
application. For instance, Rothlin and associates
[6] reported a sensitivity rate
of 90.0% and a specificity of 99.5% of the sonographic examination in patients
with blunt abdominal trauma. However, as suggested by Rozycki et al.
[18], the reason for this high
sensitivity rate was that patient outcome rather than CT was used to establish
the sensitivity of sonography. When FAST was compared with CT by McGahan et
al. [7], FAST depicted free
fluid in 63% of the patients with solid organ injuries or free fluid
identified on CT. Because free fluid has been used by most authors as the sole
criterion for a positive FAST, contained parenchymal injuries have been shown
to be missed by this approach
[7,
11].
There have been few reports of FAST being used to detect solid organ
injury. Both McGahan et al. [7]
and Rothlin et al. [6] showed a
detection rate of solid organ injuries with FAST of 41%, but most researchers
have reported a low detection rate or have not attempted to use FAST to look
for solid organ injury. Both groups of authors used a modified FAST scan,
which included not only an examination to check for free fluid, but also an
examination to evaluate the solid organs using sonography. This same approach
is used by Catalano et al.
[14] who described it as the
"full potential" sonographic technique, instead of the
"minimized" FAST evaluating only free fluid. More recently, there
have been a number of reports evaluating the use of contrast-enhanced
sonography for the detection of solid organ injury
[12-14].
For the evaluation of splenic trauma, Catalano et al.
[12] showed that avascular
splenic areas that were not visualized on non-contrast-enhanced sonography
were well seen on contrast-enhanced sonography and CT.
Miele et al. [13] also
reported promising results with contrast-enhanced sonography for the detection
of liver injuries. They concluded that contrast-enhanced sonography could be
the first diagnostic imaging study for patients with minor trauma, whereas CT
should be used in patients with more severe trauma. Catalano et al.
[14] reviewed the use of
contrast-enhanced sonography in the evaluation of liver trauma in 21 patients.
On the basis of their findings, they characterized contrast-enhanced
sonography as a promising tool in the initial assessment and follow-up of
patients with blunt liver trauma.
In another study, Catalano et al.
[19] showed contrast-enhanced
sonography to be useful for detecting intraabdominal vascular injuries, such
as ruptured abdominal aortic aneurysms. However, Poletti et al.
[9] took a more cautious
approach with the use of contrast-enhanced sonography.
They compared three different types of sonograms to CT. The initial or
admission FAST examination was compared with a non-contrast-enhanced
sonography control examination followed by contrast-enhanced sonography. They
found the detection rate of solid organ injuries for the admission FAST
examination, non-contrast-enhanced sonography, and contrast-enhanced
sonography was 40%, 57%, and 80%, respectively. Although encouraged by this
improved detection rate with contrast-enhanced sonography, they were
discouraged because 18% of solid organ injuries were missed on
contrast-enhanced sonography even after low-quality examinations had been
eliminated. Their conclusion was that contrast-enhanced sonography cannot be
recommended to replace CT in hemodynamically stable trauma patients but that
it may be helpful for detecting delayed findings such as a splenic
pseudoaneurysm.
In reviewing our data, there are several interesting observations. The
first is the difference in appearance of parenchymal organ injury between the
non-contrast-enhanced sonography and subsequent contrast-enhanced sonography
examinations. As documented by other researchers
[20-22],
the appearance of an organ injury on non-contrast-enhanced sonography may be
hyperechoic, mixed echogenic, or hypoechoic. However, this pattern changes
with the administration of contrast material. As the rest of the organ is
perfused and becomes hyperechoic, the area of injury is hypoperfused and
becomes more hypoechoic and conspicuous compared with the surrounding
parenchyma. In the spleen, the injury was often hypoechoic on
non-contrast-enhanced sonography and became more conspicuous on
contrast-enhanced sonography (Figs.
2A,
2B,
3A, and
3B). Furthermore, regions of
normal, perfused spleen could be observed within the anatomic site of injury
(Figs. 3A and
3B). This pattern occurred with
stellate splenic lacerations and has not, to our knowledge, been previously
reported using contrast-enhanced sonography. Not all spleen lacerations are
completely linear or wedge-shaped; instead, they may be more complex or
stellate, with normal areas of enhancing parenchyma seen within the region of
laceration.

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Fig. 6D Liver laceration in 32-year-old man. Contrast-enhanced
sonogram obtained in slightly different area shows there is central hypoechoic
echoic region (arrow) with surrounding perfused echogenic area
(arrowhead).
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Liver injuries were often not seen on non-contrast-enhanced sonography and
appeared hypoechoic on contrast-enhanced sonography
[14] (Figs.
4A,
4B, and
4C). In some cases, these
liver injuries appeared quite large on non-contrast-enhanced sonography and
CT, but on contrast-enhanced sonography the periphery of the injured area
stayed hyperechoic and the microbubbles were visualized. A hypoechoic region
was localized more centrally and was not perfused with administration of
contrast material. Although surgical correlation is lacking for these liver
injuries treated conservatively, it is plausible that the central hypoechoic
region is the laceration and that the surrounding hyperechoic region is
severely injured tissue that had a mixture of viable and nonviable tissues
(Figs. 5A,
5B,
5C,
6A,
6B,
6C, and
6D). This imaging appearance
was also reported by Poletti et al.
[9] who postulated that
contrast-enhanced sonography may give further insight into the true nature of
an injury. For instance, they reported a number of patients with solid organ
injuries that were not detected on contrast-enhanced sonography. These
injuries were most often minor ones, which may have been affected by edema
(contusions), whereas more significant injuries such as lacerations are seen
as hypoechoic regions on contrast-enhanced sonography. Contrast-enhanced
sonography may thus change our understanding of injuries to solid organs. If
this hypothesis is correct, contrast-enhanced sonography may have importance
in further characterizing true lacerations from injuries in which edema
(contusion) is the predominate pattern
[9]. A limitation of the study
is the small number of patients, but if this hypothesis were confirmed by a
large series, contrast-enhanced sonography could become an important adjunct
to CT in the characterization of a solid organ injury and subsequent triage to
further intervention.
Although we did not detect any pseudoaneurysms in our series, both Poletti
et al. [9] and Catalano et al.
[12] have shown that
pseudoaneurysms are clearly depicted by contrast-enhanced sonography as a
well-delineated and focal hyperechoic region. They concluded that
contrast-enhanced sonography may have a role in the detection of delayed
pseudoaneurysm from blunt abdominal trauma
[19], but this finding needs
to be confirmed with further prospective studies.
We detected all 11 subcapsular hematomas on contrast-enhanced sonography
compared with detection of only four of the 11 on non-contrast-enhanced
sonography. One explanation for this discrepancy in detection is that free
fluid appears hypoechoic on non-contrast-enhanced sonography, whereas
subcapsular hematomas are echogenic. However, with contrast-enhanced
sonography, these hematomas have little or no perfusion of contrast material,
and thus appear hypoechoic compared with normal surrounding parenchyma (Figs.
5A,
5B, and
5C).
Our study has some limitations. Although reviewers were blinded to the site
of organ injury on contrast-enhanced sonography and non-contrast-enhanced
sonography, they were not blinded to the fact that an injury had been
identified on CT. Even so, in only 50% of the cases was an injury identified
on non-contrast-enhanced sonography. This rate is not much greater than the
41% previously reported in the literature
[6,
7]. The second limitation is
that, unfortunately, not all CT planes could be exactly reproduced by
sonography because of the overlying ribs. Third, this series is limited in the
numbers of injuries. Furthermore, specificity could not be determined because
only CT images that showed injuries were included. Finally, surgical
correlation is lacking, but in most series, as in this one, CT is considered
the gold standard.
In conclusion, contrast-enhanced sonography performed better than
non-contrast-enhanced sonography for the detection of solid organ injuries. CT
is the gold standard in the evaluation of patients with blunt abdominal
trauma, and it remains the imaging study of choice in patients who are
hemodynamically stable. Non-contrast-enhanced sonography continues to have an
important role in the triage of patients with blunt abdominal trauma who are
not hemodynamically stable and cannot undergo CT. As proposed by Miele et al.
[13] and Catalano et al.
[14], there may be a future
role for contrast-enhanced sonography in initial evaluation of patients with
blunt abdominal trauma. Certainly, contrast-enhanced sonography can be used in
the follow-up of hospitalized patients with a known solid organ injury who are
managed conservatively and who cannot be easily moved to the CT suite.
Contrast-enhanced sonography could be used to help detect any changes in the
injury and spare the patient further radiation exposure.
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