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Case Report
Power Doppler Sonographic Diagnosis of
Torsion in a Wandering Spleen
Murat Danacı, MD, Ümit Belet, MD, Türkay Yalın, MD, Veysel Polat, MD, Selim Nurol, MD,
Mustafa Bekir Selçuk, MD
Department of Radiology, Ondokuz Mayıs University, School of Medicine, Kurupelit, 55139 Samsun, Turkey
Received 23 June 1999; accepted 3 November 1999
ABSTRACT: A wandering spleen is a rare clinical entity resulting from congenital maldevelopment or acquired laxity of the spleen’s suspensory ligaments; it
may result in torsion of the spleen. We report the
gray-scale sonographic, power Doppler sonographic,
and CT findings in a case of wandering spleen torsion.
The gray-scale sonograms showed a displaced spleen
that appeared as a homogeneous, hypoechoic mass
suggestive of an enlarged, ectopic spleen in the central abdomen. Power Doppler sonograms showed no
blood flow in the parenchyma or hilum of the spleen
and were consistent with torsion and infarction in the
spleen. Contrast-enhanced CT scans showed a homogeneous, unenhanced mass that was diagnosed as a
torsioned wandering spleen. The hilar vessels of the
spleen were also unenhanced. © 2000 John Wiley &
Sons, Inc. J Clin Ultrasound 28:246–248, 2000.
Keywords: wandering spleen; ultrasonography;
power Doppler ultrasonography; computed tomography
W
andering or ectopic spleen is a rare clinical
entity characterized by congenital deficiency or acquired laxity of the suspensory ligaments of the spleen. This condition may result in
splenic mobility and predispose the elongated
splenic pedicle to torsion.1 CT, sonographic, scintigraphic, and angiographic findings of torsion of
a wandering spleen have been defined.1–3 To our
knowledge, there are only 2 reports of the Doppler
sonographic findings in wandering spleen torsion,
and power Doppler sonography was not used in
these cases.2,3 We report the gray-scale sonographic, power Doppler sonographic, and CT findings in a case of wandering spleen torsion.
Correspondence to: M. Danacı
© 2000 John Wiley & Sons, Inc.
246
CASE REPORT
A 21-year-old woman presented with abdominal
pain and fever that had begun 1 week previously.
Physical examination revealed a well-defined
mass near the umbilicus and tenderness at that
site. The results of routine laboratory studies revealed that the patient had leukocytosis and
thrombocytopenia. A plain radiograph showed a
soft-tissue mass in the center of the abdomen; a
splenic silhouette was not detected in the upper
left quadrant of the abdomen, but there were gasfilled bowel loops at that location.
Sonography was performed using an SSA 270A
ultrasound scanner (Toshiba, Tokyo, Japan) and
a 3.75-MHz convex-array transducer. Gray-scale
sonography showed that the spleen was displaced
and appeared as a solid, well-defined, homogeneous, hypoechoic mass in the central abdomen.
This mass was suggestive of an enlarged, ectopic
spleen and was less echogenic than a normal
spleen would be. Tortuous vessels were observed
in the hilum of the spleen on gray-scale sonograms. Subsequently performed power Doppler
sonography showed no blood flow in the parenchyma or hilum of the spleen (Figure 1). The
splenic artery could not be followed because of
intervening bowel gas. The findings on the power
Doppler sonograms were consistent with torsion
and infarction of the spleen.
Contrast-enhanced CT scans showed a homogeneous, unenhanced mass that was diagnosed as
a torsioned wandering spleen. Hilar vessels of the
spleen were also unenhanced (Figure 2). The CT
scans showed that the location of the pancreas,
especially its tail, was normal. The appearance of
abdominal organs other than the spleen was normal on both CT scans and sonograms. Torsion
JOURNAL OF CLINICAL ULTRASOUND
TORSION IN A WANDERING SPLEEN
FIGURE 1. Power Doppler sonogram shows absence of blood flow in the parenchyma and hilum of a wandering spleen.
DISCUSSION
FIGURE 2. Contrast-enhanced CT scans obtained at 2 different levels
show that the spleen is not in its usual location and show an unenhanced, well-defined, hypodense mass suggestive of the spleen in
the abdomen. Unenhanced vascular structures are visible in the hilum of the spleen.
and acute infarction of a wandering spleen were
observed during a laparoscopy, and a splenectomy
was performed with no postoperative complications.
VOL. 28, NO. 5, JUNE 2000
The spleen is typically held in a relatively fixed
position by suspensory ligaments, surrounding
organs, and musculature. The 3 main ligaments
attached to the spleen are the lienorenal ligament, the gastrolienal ligament, and the phrenicocolic ligament. The lienorenal and gastrolienal
ligaments arise from the dorsal mesogastrium.
The posterior left reflection of this mesentery attaches the tail of the pancreas to the anterior surface of the left kidney. If this attachment is incomplete or fails to occur, the spleen can move to
any part of the abdomen and can elongate its vascular pedicle. The tail of the pancreas follows the
movements of the splenic hilum. The most serious
complication of wandering spleen is torsion of the
spleen on its pedicle 1 or more turns, leading to
infarction. The tail of the pancreas is sometimes
involved in torsion of the spleen.
Patients with torsion of wandering spleen may
have acute, chronic, or intermittent symptoms.
Affected patients may be asymptomatic, may
have mild abdominal pain due to either vascular
congestion or intermittent torsion and spontaneous detorsion, or may present with an acute abdomen due to torsion of the splenic pedicle with
subsequent infarction. Complications of acute
splenic torsion include gangrene of the spleen, abscess formation, localized peritonitis, intestinal
obstruction, and necrosis of the pancreatic tail.4
Various imaging techniques, including plain
radiography, barium enema studies, scintigraphy, gray-scale sonography, Doppler sonography,
angiography, and CT, have been used to diagnose
247
DANACI ET AL
wandering spleen.2,4 Plain radiographic findings
are usually nonspecific: an abdominal mass, the
absence of a splenic silhouette, and gas-filled
bowel loops where the splenic silhouette should
be.1 Barium enema findings may be normal or
may show bowel displacement by the ectopic
spleen.4 Scintigraphy can be valuable in the
evaluation of splenic function and may show either absence of radionuclide uptake due to splenic
torsion or normal uptake of radionuclide by an
abnormally positioned spleen. Scintigraphy has
poor anatomic resolution, however, and thus
presents little advantage over sonography or CT.4
Angiography also provides definite evidence of
splenic torsion and ectopic spleen location but is
invasive and no longer indicated for diagnosis.4
Sonographic findings in cases of wandering
spleen include the absence of a splenic image in
the normal location and the presence in the abdomen or pelvis of a homogeneous mass whose sonographic appearance is consistent with that of a
spleen.1 However, gray-scale sonographic findings provide an insufficient basis for the diagnosis
of torsion and infarction because the echogenicity
of the infarcted spleen varies from case to case.
The congested or infarcted spleen may have an altered echotexture. Despite acute infarction in the
spleen, however, the echogenicity may be normal.
Diffuse increased echogenicity of the spleen may
correspond to areas of hemorrhagic congestion at
the time of surgery.5 Use of color and duplex
Doppler sonography allows evaluation of blood
flow in the splenic parenchyma and in the major
splenic vessels.2,6 It has been reported that the
absence of sonographically detectable flow in the
splenic parenchyma may be due to insufficient
sensitivity of color and duplex Doppler sonography to slow or low-amplitude blood flow.2 Power
Doppler sonography can identify slow blood flow
and flow in small vessels, and the technique has
potential for assessing tissue perfusion and, when
used in conjunction with echo-enhancing agents,
volume-flow calculations.7
248
CT can be used to show an ectopic spleen, other
abdominal organs, the peritoneal cavity, and,
with use of a contrast agent, splenic infarction.
CT, however, is relatively expensive compared
with sonography, exposes the patient to ionizing
radiation, and frequently subjects the patient to
small but definable risks from the contrast
agent.2
We conclude that gray-scale sonography and
power Doppler sonography are valuable imaging
modalities in the diagnosis of wandering spleen
and the torsion and infarction associated with
wandering spleen. These modalities are simple,
rapid, noninvasive, and inexpensive; the patient
is not exposed to ionizing radiation; and contrast
agent injection is not needed.
REFERENCES
1. Belet U, Akan H, Kazancı F, et al. Torsion of a wandering spleen. Radiologic assessment in one case.
Radiol Med (Torino) 1998;95:125.
2. Nemcek AA Jr, Miller FH, Fitzgerald SW. Acute torsion of a wandering spleen: diagnosis by CT and
duplex Doppler and color flow sonography. AJR Am
J Roentgenol 1991;157:307.
3. Berkenblit RG, Mohan S, Bhatt GM, et al. Wandering spleen with torsion: appearance on CT and ultrasound. Abdom Imaging 1994;19:459.
4. Herman TE, Siegel MJ. CT of acute splenic torsion
in children with wandering spleen. AJR Am J
Roentgenol 1991;156:151.
5. Newman B, Bowen A, Eggli KD. Recognition of malposition of the liver and spleen: CT, MRI, nuclear
scan and fluoroscopic imaging. Pediatr Radiol 1994;
24:274.
6. Garcia JA, Garcia-Fernandez M, Romance A, et al.
Wandering spleen and gastric volvulus. Pediatr Radiol 1994;24:535.
7. Sutton D, Gregson R. Arteriography and interventional angiography. In: Sutton D, editor. Textbook of
radiology and imaging. New York: Churchill Livingstone; 1998. p 673.
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