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1101
Ligamentous Celiac Axis:
Compression CT Findings
of the
in Five
Patients
Randall M. Patten1 Douglas M. CoIdwell Yoram Ben-Menachern
Compression an uncommon
of the celiac trunk by the median angiographic and surgical finding
retrospectively
reviewed
contrast-enhanced
arcuate ligament of the diaphragm is that rarely may be symptomatic. We
abdominal
CT scans
in five patients
with
severe ligamentous compression of the celiac axis, confirmed by surgery and/or angiography, and compared the findings with those of enhanced scans of 100 consecutive patients without known ligamentous compression. In all five patients with ligamentous celiac artery compression, CT showed effacement or narrowing of the celiac trunk by an anterior soft-tissue band. Dilated penpancreatic collateral vessels were seen in four cases, and poststenotic dilatation of the distal celiac trunk was seen in two cases. The normal appearance of the vasculature was seen in the majority (76%) of the 100 control subjects, but in eight patients the celiac origin was obscured on CT scans, and in 16 patients the celiac trunk appeared narrow or effaced. Our experience suggests that severe ligamentous celiac artery compression can be identified on CT. However, the isolated CT finding of effacement or obscuration of the celiac axis occurs sufficiently often in normal patients that it is not adequate evidence to establish the diagnosis of celiac artery compression. AJR
156:1101-1103, May 1991
Compression
and stenosis
of the celiac trunk by the median arcuate
the diaphragm is a well-recognized angiographic by the following: moderate to severe stenosis by
compression
by fibrous diaphragmatic
ligament
of
and surgical finding, characterized of the proximal celiac trunk caused
bands, poststenotic
portion of the celiac axis, and the formation of collateral ligament syndrome occurs in a select group of patients
dilatation
of the distal
vessels. Median arcuate with celiac compression
who have abdominal anginalike symptoms and who may benefit from surgical division of the ligamentous band. Although the syndrome was first reported in 1963 [1] and angiographic findings were described in 1965 [2], the CT finding of celiac compression by the median arcuate ligament has not been previously reported. We describe the CT appearance of severe ligamentous compression of the celiac trunk
in five cases
Materials
after re(56-05),
University of Washington School of Medicine, 199 N.E. Pacific St., Seattle, WA 981 95. Address reprint requests to R.M. Patten at Rainier Medical Imaging Center, 1 1 81 1 N.E. 1 28th St., Kirkland, WA 98034. 0361-803X/91/1
65-1101
© American Roentgen Ray Society
angiographic
and surgical
correlation.
and Methods
We retrospectively Received October 12, 1990: accepted vision November 1 2, 1990. 1 All authors: Department of Radiology,
with
reviewed
the abdominal
CT findings in five cases of severe celiac axis
stenosis encountered in a 4-year period. The diagnosis of celiac artery compression by the median arcuate ligament of the diaphragm was established by characteristic appearance on
aortography and selective splanchnic arteriography in all cases and was confirmed surgically in three cases. Angiographic criteria for the diagnosis included eccentric stenosis of the proximal celiac trunk, delayed filling of the celiac branches by collateral flow, and lack of atherosclerosis in other vessels (Figs. 1 and 2A). In the three surgically proved cases, the proximal celiac axis was bound tightly to the aorta by fibrous and ligamentous bands from the diaphragmatic crura. In the two remaining cases, surgery was not performed.
CT studies were performed
for evaluation
of metastatic
arising
disease (three patients), abdominal
trauma (one patient), and abdominal pain (one patient). The median arcuate ligament syndrome was not clinically suspected in any of the patients. There were four men and one woman in the series, ranging
performed
during
bolus administration
oflV
a GE 8800 or 9800 scanner (Milwaukee, axial slices at 10-mm intervals.
contrast
material
by using
WI) and 10-mm collimated
in age from 19 to 67 years (average age, 52 years). CT findings about the celiac five
axis were
cases)
and
tabulated
surgical
and correlated
findings
(three
with
angiographic
(all
Results
cases).
To determine whether CT findings about the celiac axis in these patients were specific for the diagnosis of significant median arcuate
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ligament
compression,
we compared
the CT appearance
of the celiac
axis in patients
with ligamentous celiac compression with the apof the celiac trunk in 1 00 consecutive patients undergoing
pearance IV contrast-enhanced abdominal CT studies for unrelated CT studies were performed for evaluation of suspected metastatic disease (52 cases), abdominal pain (27 cases),
cases), and miscellaneous men and 46 women
56 years).
ranging
indications
(eight cases). There were 54
in age from
All CT examinations
reasons.
or known trauma (13
(study
8 to 87 years (average
and control
groups)
age,
were
In all five cases, effacement of the celiac axis was apparent on the CT scans. A thin, discrete, soft-tissue band extending
across
the anterior
aspect
of the celiac trunk
was seen in
three
patients (Fig. 2B), whereas in the other two patients a more poorly defined linear soft-tissue density obscured the origin of the celiac trunk. In two patients, CT showed poststenotic dilatation of the celiac trunk anterior to the soft-tissue band (Fig. 3), a finding confirmed angiographically in both cases. At angiography, occlusion or severe stenosis of the celiac trunk was seen in all five patients. Branches of the celiac artery were filled by retrograde collateral flow from the gastroduodenal artery, pancreaticoduodenal arteries, and pancreatic arcade. Large collateral vessels about the pancreatic
head and dilatation
of the gastroduodenal
artery were seen
on contrast-enhanced CT images in four cases (Fig. 2C). In one patient, examined because of abdominal trauma,
CT
showed acute occlusion of the left renal artery and complex splenic lacerations in addition to effacement of the celiac artery. CT findings about the celiac axis, initially to be due to acute vascular trauma, were correctly
as median arcuate confirmed
ligament
at laparotomy.
was complicated
compression Surgical
by bleeding
Fig. 1.-61-year-old
man with colonic carcinoma
and solitary resectable
metastasis to left lobe of liver. Lateral aortogram shows marked narrowing of cellac trunk from extrinsic superior impression (arrow). Note poststenotic dilatation of distal celiac artery (C). Compression by median
arcuate ligament was found at surgery. S = superior mesenteric
artery.
at angiography
exploration
from multiple
the pancreatic arcade. In one patient, examined for chronic inal pain, celiac artery compression radiologic finding. Further diagnostic
interpreted diagnosed
and
in this patient
collaterals
within
poorly defined abdomwas the only positive workup was negative.
However, the patient refused surgical intervention. Review of CT findings about the celiac axis in the control patients majority
showed normal appearances (76%) of subjects. The celiac
of the vessels in the trunk was well opaci-
Fig. 2.-67-year-old woman with significant ligamentous compression of celiac trunk. A, Selective superior mesenteric arteriogram shows nearly complete occlusion of celiac trunk (arrowheads) and slow retrograde filling distribution through enlarged and tortuous pancreaticoduodenal arcade (P). C = distal celiac trunk, S = superior mesenteric artery. B, CT scan at level of origin of celiac axis shows thin soft-tissue band (arrowheads) and apparent discontinuity of celiac trunk and common
of celiac hepatic
artery (ha). This apparent vascular interruption could be result of partial volume artifact, although this explanation would not account for difference in densIties between aorta (Ao), hepatic artery, and large collateral branch of pancreaticoduodenal arcade (arrow). I = inferior vena cava. C, CT scan at level slightly Inferior to B shows multiple collateral vessels (arrowheads) in pancreaticoduodenal arcade. Ao = aorta, I = inferior vena cava, S = superior mesenteric vein, arrow = superior mesenteric artery.
tration of IV contrast material and thinly collimated axial slices through the region of the celiac trunk, these cases were identified only in retrospect and therefore CT evaluation of the celiac axis was not optimized for each case. Nevertheless, characteristic findings of a soft-tissue band anterior to the celiac artery and the presence of peripancreatic collateral
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vessels
were noted.
Occasionally,
poststenotic
dilatation
of
the celiac trunk also may be seen distal to the constricting band. The sensitivity and specificity of these findings are unknown. Effacement or poor definition of the origin of the celiac trunk on thick axial CT scans is encountered frequently
as a normal
variant
or as a consequence
artifact. If collateral finding of effacement
reliable Fig. 3.-56-year-old
man with celiac compression.
CT scan at level of
celiac axis shows compression of celiac trunk by a thin ligamentous band (arrows). Note poststenotic dilatation of distal celiac trunk (C). Ao = aorta; I = inferior vena cava.
fled, and its origin from the abdominal aorta was In eight patients, the origin of the celiac trunk clearly defined; in 1 6 patients, the celiac trunk be effaced or narrowed. Collateral vessels about the pancreas and poststenotic dilatation of the were not seen in any of these patients.
clearly seen. could not be appeared to the head of celiac trunk
Discussion
The crura on either side of the aortic hiatus are united by a fibrous arch, the median arcuate ligament. Usually, this ligament passes posteriorly and inferiorly to the origin of the celiac axis. In 1 965, Dunbar and colleagues [2] described a clinical syndrome of postprandial abdominal pain and malabsorption attributed to compression of the celiac trunk by the unyielding median arcuate ligament passing anterior to the artery and tightly compressing it against the aorta. Surgical ligation of the constricting ligamentous band has been performed with variable success [3-7], and many surgeons no longer accept the “median arcuate ligament syndrome” as a clinical entity [8]. Although controversy regarding the clinical syndrome continues, compression of the celiac axis by the median arcuate ligament is a well-documented anatomic variant, seen to variable degree in from 1 0% to 24% of patients [9]. The origin of the celiac trunk undergoes variable caudal migration during embryogenesis, and may vary in location from the level of the 1 1 th thoracic to the first lumbar vertebra; either a high celiac origin or an inferior extension of the median arcuate ligament may therefore contribute to ligamentous compression of the celiac artery. Variable degrees of compression of the celiac trunk have been demonstrated by angiography in 1 3% to 50% of patients [8, 1 0, 1 1 ], and severe stenosis of the celiac axis may be found in 1% of abdominal arteriograms [12]. Severe stenosis of the celiac trunk is commonly associated with enlargement of the arteries of the pancreaticoduodenal arcade, which supply the distribution of the celiac axis via retrograde flow from the superior mesenteric artery. The five cases presented demonstrate that severe compression of the celiac axis can be recognized by CT also. Although optimal CT technique would include bolus adminis-
of partial-volume
vessels are not recognized, the solitary of the celiac axis does not appear to be
CT evidence
for the diagnosis
of significant
celiac
artery compression. Although median arcuate ligament syndrome remains a controversial clinical syndrome, the ability to recognize significant celiac artery compression by CT is nevertheless important. In the acutely traumatized patient, effacement of the celiac trunk from a constricting band may erroneously suggest arterial injury. Moreover, the presence of multiple collateral
vessels associated poses a significant
with severe stenosis of the celiac trunk surgical risk and should be recognized on
preoperative CT. Additionally, for the unwary angiographer, there is increased risk of arterial dissection due to repeated
attempts
at catheterization
of the celiac artery when the trunk
is significantly compressed. of embolization of hepatic
catheterization
This is particularly tumors in which
is necessary.
true in the case superselective
As most of these
patients
are
examined with abdominal CT, attention to the celiac axis may alert the angiographer to potential difficulties. Finally, in some patients with severe celiac artery compression, chronic abdominal pain, and malabsorption, surgical resection of the
constricting cure.
median arcuate
In these
findings
cases,
may suggest
ligament
recognition
proper
may provide a definitive of the
diagnosis
characteristic
CT
and therapy.
REFERENCES 1 . Harjola PT. A rare obstruction 1963:52:547
of the coeliac artery. Ann Chir Gynaecol
2. Dunbar JD, Molnar W, Beman FF, Marable SA. Compression of the celiac trunk and abdominal angina. AJR 1965:95:731-743 3. Stoney RJ, Wylie EJ. Recognition and surgical management of visceral ischemic syndromes. Ann Surg 1966:164:714-721 4. Marable SA, Kaplan MF, Beman FF, et al. Celiac compression syndrome. AmJSurg 1968:115:97-102 5. Carey JP, Stemmer EA, Connolly JE. Median arcuate ligament syndrome: experimental and clinical observations. Arch Surg 1969:99:441-446
6. Kemohan RM, Barros AAB, Cranley B, Johnston
HML. Further evidence
supporting the existence of the celiac artery compression syndrome. Arch Surg 1985:120: 1072-1 076 7. Plate G, Eklof B, Vang J. The celiac compression syndrome: myth or reality? Acta Chir Scand 1981:147:201-203
8. Szilagyi DE, Ryan RL, Elliott JP, Smith JP. The celiac artery compression syndrome:
does it exist?
Surgery
1972:72:849-863
9. Lindner HH, Kemprud E. A clinicoanatomic study of the arcuate ligament of the diaphragm. Arch Surg 1971 :1 03 :600-605 10. Bron KM, Redman HC. Splanchnic artery stenosis and occlusion: mcidence, arteriographic and clinical manifestations. Radiology 1969:92 :323328 1 1 . Reuter S. Accentuation of celiac compression by the median arcuate ligament ofthe diaphragm during deep expiration. Radiology 1971:98:561 12. Cornell without
S. Severe symptoms.
stenosis of celiac axis: Radiology 1971:99:311
analysis
of patients
with
and