Julia
E. Roshkow,
MD
#{149} Linda
M. Sanders,
MD
Acute Splenic Sequestration Two Adults with Sickle Us, CT, and MR Imaging
Crisis Cell Disease: Findings’
in
splenic sequestration crisis (ASSC) is a rare complication in adults with sickle cell disease that is diagnosed clinically by means of sudden splenic enlargement and a rapid fall in hematocrit. Two cases of ASSC in adults with heterozygous sickle cell disease (sickle cell-thalassemia and sickle cell-hemoglobin C disease) were studied with use of duplex Doppler ultrasound (US), cornputed tomography (CT), and magnetic resonance (MR) imaging. In both cases, US showed patency of the splenic vein and multiple hypoechoic lesions on the periphery of an enlarged spleen that were of low attenuation on CT scans and hyperintense on both Ti- and T2-weighted MR images. These findings were believed to be suggestive of subacute hemorrhage. This was confirmed pathologically in one case and suggested in the other by the presence of a low-signal-intensity ring, probably hemosiderin, surrounding one of the lesions. Also, the remainder of the spleen in both patients was of normal signal intensity, unlike the diminished signal intensity seen in patients with homozygous sickle cell disease. Further study is needed to determine the role of imaging in the diagnosis and treatment of ASSC. Acute
Index terms: Sickle cell disease (SS, SC), 775.651 #{149} Spleen, CT, 775.1211 #{149} Spleen, MR studies, 775.1214 #{149} Spleen, US studies, 775.12984 Radiology
1990;
177:723-725
splenic sequestration crisis (ASSC), a complication of sickle cell disease, is rare in adults. To our knowledge, only 10 cases of ASSC in adults have been reported in the literature (1-7). It is diagnosed clinically by sudden splenic enlargement accompanied by a rapid fall in hematocrit (6,8). ASSC occurs predominantly in infants and young children with homozygous sickle cell disease but can also occur in adults with heterozygous sickle cell disease, particularly those with sickle cell-thalassemia and sickle cell-hemoglobin C disease (9). We report two cases of ASSC in adults studied with use of duplex Doppler ultrasound (US), computed tomography (CT), and magnetic resonance (MR) imaging. To our knowledge, duplex Doppler US and MR findings in this entity have not previously been described. CUTE
acute episode (Shelton,
tamed.
sickle
cell
REPORTS
31-year-old thalassemia
and
two
man with prior
epi-
sodes of ASSC presented with pain in the back and knees. He had received multiple transfusions prior to this admission. At admission, unremarkable;
his
physical his spleen
ble, his hematocrit
examination was not
was palpa-
was 32.3% (0.323),
his
hemoglobin level was 10.4 g/dL (104 g/ L), and his platelet count was 183,000/ mm3 (183 X 109/L). A reticulocyte count
was not obtained four hours left upper
now
enlarged.
creased
to
level
at that time.
later, he complained quadrant pain. His
His hematocrit
17.9%
(0.179),
his
and CT were hyperintense ed images and markedly
T2-weighted
images
perintense sent either
areas were hemorrhage
infarction.
The
to liver
had dehemoglobin
(Fig la).
low-attenuation areas that to the US findings (Fig ib). were believed to represent eior infarction.
MR imaging
was performed
thought to repreor hemorrhagic of the
signal
on proton
intensity,
density
to liver
on
hy-
spleen
isointense
images
and
on T2-weighted
hy-
im-
ages.
The patient
was stabilized
change transfusion, performed 14 days
and after
with
ex-
splenectomy was the acute epi-
sode. The spleen weighed 880 g. The capsule was intact. The cut surface showed irregular
areas
of yellow
that corresponded seen
on the
images.
these
disco!-
to the focal
le-
At histologic
areas
were
hemor-
rhagic infarcts, approximately 10-14 days old. Congestion was noted, and the sinusoids were packed with sickled erythrocytes. In addition, hemosiderin granules
were scattered throughout Case 2.-A 36-year-old
the spleen. black man with sickle cell-hemoglobin C disease presented with pain in the back and extremities. He had been hospitalized numerous times since the age of 9 years for typical painful crises but had no prior history of sion. At admission, his spleen was not palpable, his hematocrit was 32.3% (0.323), his hemoglobin level was 10.7 g/ dL (107 gIL), his platelet count was 47,000/mm3 (470 X 109/L), and his reticu-
examination revealed a patent vein, as well as patency of large intrasplenic veins. A CT scan obtained with the dynamic bolus technique on day 2 (GE 9800; GE Medical Systems, Milwau-
them hemorrhage
(Fig ic). These
remainder
was of normal perintense
on Ti-weighthyperintense
ASSC and had never
Doppler splenic
kee) showed corresponded These areas
ob-
of new spleen was
(59 gIL), his platelet was 121,000/mm3 (121 X 109/L), his reticulocyte count was 12.6% X 10). US study performed on day 2 (Acu128 [sector probe 5328 MHz]; Acuson, Mountain View, Calif) showed a 19cm spleen with multiple hypoechoic ardistribution
were
sequences
Twenty-
was 5.9 g/dL
eas in a peripheral
sections
spin-echo
examination,
black
use of a Philips operating at 0.5
were used for proton density and T2 weighting (repetition time msec/echo time msec 716/20, 2,250/50, 100). The focal lesions within the spleen seen at US
sions
CASE
axial
Standard
oration
Case 1.-A
with Conn)
T. Ten-millimeter
multiple
count and (126 A son
I From the Department of Radiology, Columbia Presbyterian Medical Center, 622 W 168th St, New York, NY 10032. Received April 5, 1 990; revision requested May 25; revision received July 17; accepted July 18. Address reprint requests to L.M.S. 0 RSNA, 1990
ter the Gyroscan
7 days af-
locyte
count
four hours
received
a transfu-
was 7% (70 X 10). Twentyafter admission, he described
an unusual
feeling
“stiffness.”
His
of left
spleen
was
upper now
quadrant palpable.
His hematocrit had dropped to 18.4% (0.184), his hemoglobin level was 6.0 g/ dL (60 gIL), and his reticulocyte count
wasli%(11OX
10).
US performed cm spleen with
on day 1 showed an 18two small hypoechoic ar-
eas in the periphery. The splenic were patent. A CT scan obtained confirmed
the
imaging
(366/20,
Abbreviation: tration crisis.
US findings
2,016/50,
ASSC
=
acute
veins on day 4
(Fig
2a). MR
100)
per-
splenic
seques-
723
b.
a. Figure
1.
(a) US scan
be markedly
demonstrates hyperintense.
technique
formed sions
on day
shows the
5 showed
corresponding
size.
He
admission [0.370]),
was
discharged
with
a stable
persistent
hyperintense US
and
c.
lesions
splenic lesions spleen demonstrates
(arrows)
in an enlarged
spleen.
(b) CT scan
of low attenuation. (c) T2-weighted a normal hyperintensity to liver,
obtained
with
MR image (2,250/ which is unusual
use of dynamic
bolus
100) shows these lesions in sickle cell disease.
to
leCT
lesion in the anteridemonstrated a pering believed to a transfusion, and spleen decreased 12 days
after
hematocrit
11
(37%
thrombocytopenia X 109/L]), and a nonpalperformed 4 months lat-
(66,000/mm3 [66 pable spleen. US em showed an enlarged cal
hypoechoic
same peripheral The rest of the
to the
findings (Fig 2b). The or aspect of the spleen riphemal low-intensity represent hemosidemin. The patient received over the next week his in
peripheral
spleen
without
fo-
jd
abnormality.
DISCUSSION The diagnosis of ASSC is based on a sudden, massive enlargement of the spleen accompanied by a rapid decrease in hematocrit and evidence of marrow activity, such as a reticulocyte count greater than or equal to steadystate values (8). Evidence of marrow activity serves to differentiate ASSC from aplasia (8). Often thrombocytopenia is seen as well. A major episode is defined as one in which the hemoglobin level is less than 6 g/dL (60 g/L) and has fallen more than 3 g/dL (30 gIL), while a minor episode is one in which the hemoglobin level is greater than 6 g/dL (60 g/L) (9). Since distensibility of the spleen is essential to these episodes, ASSC is usually seen in children under the age of 6 years with homozygous sickle cell disease (6). In fact, this complication accounts for almost 50% of deaths in children under 2 years of age with sickle cell disease (10). ASSC is rare past the age of 8 years due to progressive splenic fibrosis (6). However, in adults with sickle cell-thalassemia and sickle cellhemoglobin C disease, an enlarged,
724
Radiology
#{149}
a.
b.
Figure sions. sions,
2.
(a) CT scan
(b) T2-weighted one of which
shows an enlarged MR image (2,016/ has a low-intensity
spleen with two 100) demonstrates rim (arrow).
and presumably distensible, spleen is common (9). ASSC might, therefore, occur in these patients. The rarity of ASSC in adults may be due to a relatively low susceptibility to this complication or to underdiagnosis, particular-
smaller
ly
nectomy
of
minor
episodes
(6).
intrasplenic
The
initial
sion
more
likely
occurs
at the
obstruction
level
of the
dies
response rapid,
of splenic
with
the
within
a subsequent
hamper
Sple-
adults
or red
may
is
transfu-
to baseline. for
episodes that
to
size
is reserved
infarction.
the
The
is usually
return
US.
that
or
of ASSC
treatment
transfusion.
current
suggests
veins
lele-
sinusoids.
The pathogenesis of ASSC is unknown. The triggering event may be acute obstruction to venous outflow from the spleen leading to sequestration of red cells and, often, of platelets as well (6). Experimental ligation of the splenic vein in animals produces a similar syndrome with splenic enlargement and a decrease in hematocrit (11). Both of our patients, however, had normal flow in the splenic vein and large intrasplenic veins as shown by Doppler This
peripheral low-attenuation two high-signal-intensity
with
cell transfusion
(6).
Liver-spleen
scanning
with
use
technetium-99m
sulfur
colloid
has
shown
an
enlarged
spleen
inhomogeneous or
fects
(3,5,6).
areas of
of
scans
visualization appearance
show
the
US
shows with
CT scans attenuation,
poor,
spleen.
Folbetter
with the seen focal
focal
disde-
hypoechoic
hemorrhage show similar most
of
defects,
progressively
of the spleen of previously
consistent low
with
focal
uptake,
nonvisualization
low-up
me-
alloantibo-
or areas
commonly
pe-
December
1990
ripheral, which may be interspersed with areas of higher attenuation due to recent hemorrhage (4). MR imaging in both our patients showed focal lesions within the spleen that
were
rest
of the spleen
weighted
hyperintense images,
relative
on both consistent
to the
Ti- and with
177
#{149} Number
3
ed
to determine
the
the diagnosis ASSC. U
and
role
of
imaging
treatment
in
6.
7.
8.
References River
CL,
Robbins
hemoglobin:
AB, Schwartz
a clinical
study.
SO. S-C Blood 1961;
18:385-416.
2.
3.
Fullerton WT, Hendrickse JP, Watson-Wilhams EJ. Hemoglobin SC disease in pregnancy. In: JonxisJHP, ed. Abnormal hemoglobins in Africa. Philadelphia: Davis, 1965; 411-433. Geola F, Kukreja SC, Schade SG. Splenic sequestration with sickle cell-C disease.
Arch 4.
5.
Intern
posplenism Am
J Hematol
9.
in hemoglobin 1985;
S-C disease.
CC, Castro 0. Acute crises in adults with Am J Med 1986; 80:985-
cell disease.
Bowcock
SJ,
Nwabueze
11.
12.
ED,
Cook
AE,
Aboud HH, Hughes RG. Fatal splenic soquestration in adult sickle cell disease. Clin Lab Haematol 1988; 10:95-99. Topley JM, Rogers DW, Stevens MCG, Serjeant CR. Acute splenic sequestration and hypersplenism in the first five years in homozygous sickle cell disease. Arch Dis Child 1981; 56:765-769. Williams WJ, Beutler E, Erslev AJ, Lichtman MA. Hematology. New York:
McGraw-Hill, 10.
Med 1978; 138:307-308.
Magid D, Fishman EK, Siegelman SS. Computed tomography of the spleen and liver in sickle cell disease. AJR 1984; 143:245-249. Sear DA, Udden MM. Splenic infarction, splenic sequestration, and functional hy-
DL, Kletter sequestration
990.
T2-
1.
Solanki splenic
sickle
of
hem-
orrhage. This was confirmed pathologically in one case, and in the other, a low-signal-intensity “hemosiderin ring” was highly suggestive of hemorrhage. Adler et a! (12) compared the appearance of the spleen in 13 patients with sickle cell disease with that of 60 healthy patients and found abnormally diminished splenic intensity relative to liver and paraspinal muscle on T2weighted images in all 13 patients. This finding was not seen in either of our patients, which may be due to the heterozygous, rather than homozygous, nature of their sickle cell disease. To our knowledge, there have been no reports of the usual MR appearance of
Volume
the spleen in patients with heterozygous sickle cell disease. In conclusion, further study is need-
1983.
Emond
AM,
Maude
GH, Serjeant
D, Higgs DR. Acute splenic sequestration in homozygous sickle cell disease: natural history and management. J Pediatr 1985; 107:201-206. Altman KI, Watman RN, Solomon K. Surgically induced splenogenic anemia in the rabbit. Nature 1951; 168:827. Adler DD, Glazer GM, Aisen AM. MRI of
the spleen: ings
Collis
normal
in sickle-cell
R, Darvill
CR.
appearance anemia.
AJR
and find1986;
147:843-845.
18:261-268.
Radiology
#{149} 725
E. Roshkow,
MD
#{149} Linda
M. Sanders,
MD
Acute Splenic Sequestration Two Adults with Sickle Us, CT, and MR Imaging
Crisis Cell Disease: Findings’
in
splenic sequestration crisis (ASSC) is a rare complication in adults with sickle cell disease that is diagnosed clinically by means of sudden splenic enlargement and a rapid fall in hematocrit. Two cases of ASSC in adults with heterozygous sickle cell disease (sickle cell-thalassemia and sickle cell-hemoglobin C disease) were studied with use of duplex Doppler ultrasound (US), cornputed tomography (CT), and magnetic resonance (MR) imaging. In both cases, US showed patency of the splenic vein and multiple hypoechoic lesions on the periphery of an enlarged spleen that were of low attenuation on CT scans and hyperintense on both Ti- and T2-weighted MR images. These findings were believed to be suggestive of subacute hemorrhage. This was confirmed pathologically in one case and suggested in the other by the presence of a low-signal-intensity ring, probably hemosiderin, surrounding one of the lesions. Also, the remainder of the spleen in both patients was of normal signal intensity, unlike the diminished signal intensity seen in patients with homozygous sickle cell disease. Further study is needed to determine the role of imaging in the diagnosis and treatment of ASSC. Acute
Index terms: Sickle cell disease (SS, SC), 775.651 #{149} Spleen, CT, 775.1211 #{149} Spleen, MR studies, 775.1214 #{149} Spleen, US studies, 775.12984 Radiology
1990;
177:723-725
splenic sequestration crisis (ASSC), a complication of sickle cell disease, is rare in adults. To our knowledge, only 10 cases of ASSC in adults have been reported in the literature (1-7). It is diagnosed clinically by sudden splenic enlargement accompanied by a rapid fall in hematocrit (6,8). ASSC occurs predominantly in infants and young children with homozygous sickle cell disease but can also occur in adults with heterozygous sickle cell disease, particularly those with sickle cell-thalassemia and sickle cell-hemoglobin C disease (9). We report two cases of ASSC in adults studied with use of duplex Doppler ultrasound (US), computed tomography (CT), and magnetic resonance (MR) imaging. To our knowledge, duplex Doppler US and MR findings in this entity have not previously been described. CUTE
acute episode (Shelton,
tamed.
sickle
cell
REPORTS
31-year-old thalassemia
and
two
man with prior
epi-
sodes of ASSC presented with pain in the back and knees. He had received multiple transfusions prior to this admission. At admission, unremarkable;
his
physical his spleen
ble, his hematocrit
examination was not
was palpa-
was 32.3% (0.323),
his
hemoglobin level was 10.4 g/dL (104 g/ L), and his platelet count was 183,000/ mm3 (183 X 109/L). A reticulocyte count
was not obtained four hours left upper
now
enlarged.
creased
to
level
at that time.
later, he complained quadrant pain. His
His hematocrit
17.9%
(0.179),
his
and CT were hyperintense ed images and markedly
T2-weighted
images
perintense sent either
areas were hemorrhage
infarction.
The
to liver
had dehemoglobin
(Fig la).
low-attenuation areas that to the US findings (Fig ib). were believed to represent eior infarction.
MR imaging
was performed
thought to repreor hemorrhagic of the
signal
on proton
intensity,
density
to liver
on
hy-
spleen
isointense
images
and
on T2-weighted
hy-
im-
ages.
The patient
was stabilized
change transfusion, performed 14 days
and after
with
ex-
splenectomy was the acute epi-
sode. The spleen weighed 880 g. The capsule was intact. The cut surface showed irregular
areas
of yellow
that corresponded seen
on the
images.
these
disco!-
to the focal
le-
At histologic
areas
were
hemor-
rhagic infarcts, approximately 10-14 days old. Congestion was noted, and the sinusoids were packed with sickled erythrocytes. In addition, hemosiderin granules
were scattered throughout Case 2.-A 36-year-old
the spleen. black man with sickle cell-hemoglobin C disease presented with pain in the back and extremities. He had been hospitalized numerous times since the age of 9 years for typical painful crises but had no prior history of sion. At admission, his spleen was not palpable, his hematocrit was 32.3% (0.323), his hemoglobin level was 10.7 g/ dL (107 gIL), his platelet count was 47,000/mm3 (470 X 109/L), and his reticu-
examination revealed a patent vein, as well as patency of large intrasplenic veins. A CT scan obtained with the dynamic bolus technique on day 2 (GE 9800; GE Medical Systems, Milwau-
them hemorrhage
(Fig ic). These
remainder
was of normal perintense
on Ti-weighthyperintense
ASSC and had never
Doppler splenic
kee) showed corresponded These areas
ob-
of new spleen was
(59 gIL), his platelet was 121,000/mm3 (121 X 109/L), his reticulocyte count was 12.6% X 10). US study performed on day 2 (Acu128 [sector probe 5328 MHz]; Acuson, Mountain View, Calif) showed a 19cm spleen with multiple hypoechoic ardistribution
were
sequences
Twenty-
was 5.9 g/dL
eas in a peripheral
sections
spin-echo
examination,
black
use of a Philips operating at 0.5
were used for proton density and T2 weighting (repetition time msec/echo time msec 716/20, 2,250/50, 100). The focal lesions within the spleen seen at US
sions
CASE
axial
Standard
oration
Case 1.-A
with Conn)
T. Ten-millimeter
multiple
count and (126 A son
I From the Department of Radiology, Columbia Presbyterian Medical Center, 622 W 168th St, New York, NY 10032. Received April 5, 1 990; revision requested May 25; revision received July 17; accepted July 18. Address reprint requests to L.M.S. 0 RSNA, 1990
ter the Gyroscan
7 days af-
locyte
count
four hours
received
a transfu-
was 7% (70 X 10). Twentyafter admission, he described
an unusual
feeling
“stiffness.”
His
of left
spleen
was
upper now
quadrant palpable.
His hematocrit had dropped to 18.4% (0.184), his hemoglobin level was 6.0 g/ dL (60 gIL), and his reticulocyte count
wasli%(11OX
10).
US performed cm spleen with
on day 1 showed an 18two small hypoechoic ar-
eas in the periphery. The splenic were patent. A CT scan obtained confirmed
the
imaging
(366/20,
Abbreviation: tration crisis.
US findings
2,016/50,
ASSC
=
acute
veins on day 4
(Fig
2a). MR
100)
per-
splenic
seques-
723
b.
a. Figure
1.
(a) US scan
be markedly
demonstrates hyperintense.
technique
formed sions
on day
shows the
5 showed
corresponding
size.
He
admission [0.370]),
was
discharged
with
a stable
persistent
hyperintense US
and
c.
lesions
splenic lesions spleen demonstrates
(arrows)
in an enlarged
spleen.
(b) CT scan
of low attenuation. (c) T2-weighted a normal hyperintensity to liver,
obtained
with
MR image (2,250/ which is unusual
use of dynamic
bolus
100) shows these lesions in sickle cell disease.
to
leCT
lesion in the anteridemonstrated a pering believed to a transfusion, and spleen decreased 12 days
after
hematocrit
11
(37%
thrombocytopenia X 109/L]), and a nonpalperformed 4 months lat-
(66,000/mm3 [66 pable spleen. US em showed an enlarged cal
hypoechoic
same peripheral The rest of the
to the
findings (Fig 2b). The or aspect of the spleen riphemal low-intensity represent hemosidemin. The patient received over the next week his in
peripheral
spleen
without
fo-
jd
abnormality.
DISCUSSION The diagnosis of ASSC is based on a sudden, massive enlargement of the spleen accompanied by a rapid decrease in hematocrit and evidence of marrow activity, such as a reticulocyte count greater than or equal to steadystate values (8). Evidence of marrow activity serves to differentiate ASSC from aplasia (8). Often thrombocytopenia is seen as well. A major episode is defined as one in which the hemoglobin level is less than 6 g/dL (60 g/L) and has fallen more than 3 g/dL (30 gIL), while a minor episode is one in which the hemoglobin level is greater than 6 g/dL (60 g/L) (9). Since distensibility of the spleen is essential to these episodes, ASSC is usually seen in children under the age of 6 years with homozygous sickle cell disease (6). In fact, this complication accounts for almost 50% of deaths in children under 2 years of age with sickle cell disease (10). ASSC is rare past the age of 8 years due to progressive splenic fibrosis (6). However, in adults with sickle cell-thalassemia and sickle cellhemoglobin C disease, an enlarged,
724
Radiology
#{149}
a.
b.
Figure sions. sions,
2.
(a) CT scan
(b) T2-weighted one of which
shows an enlarged MR image (2,016/ has a low-intensity
spleen with two 100) demonstrates rim (arrow).
and presumably distensible, spleen is common (9). ASSC might, therefore, occur in these patients. The rarity of ASSC in adults may be due to a relatively low susceptibility to this complication or to underdiagnosis, particular-
smaller
ly
nectomy
of
minor
episodes
(6).
intrasplenic
The
initial
sion
more
likely
occurs
at the
obstruction
level
of the
dies
response rapid,
of splenic
with
the
within
a subsequent
hamper
Sple-
adults
or red
may
is
transfu-
to baseline. for
episodes that
to
size
is reserved
infarction.
the
The
is usually
return
US.
that
or
of ASSC
treatment
transfusion.
current
suggests
veins
lele-
sinusoids.
The pathogenesis of ASSC is unknown. The triggering event may be acute obstruction to venous outflow from the spleen leading to sequestration of red cells and, often, of platelets as well (6). Experimental ligation of the splenic vein in animals produces a similar syndrome with splenic enlargement and a decrease in hematocrit (11). Both of our patients, however, had normal flow in the splenic vein and large intrasplenic veins as shown by Doppler This
peripheral low-attenuation two high-signal-intensity
with
cell transfusion
(6).
Liver-spleen
scanning
with
use
technetium-99m
sulfur
colloid
has
shown
an
enlarged
spleen
inhomogeneous or
fects
(3,5,6).
areas of
of
scans
visualization appearance
show
the
US
shows with
CT scans attenuation,
poor,
spleen.
Folbetter
with the seen focal
focal
disde-
hypoechoic
hemorrhage show similar most
of
defects,
progressively
of the spleen of previously
consistent low
with
focal
uptake,
nonvisualization
low-up
me-
alloantibo-
or areas
commonly
pe-
December
1990
ripheral, which may be interspersed with areas of higher attenuation due to recent hemorrhage (4). MR imaging in both our patients showed focal lesions within the spleen that
were
rest
of the spleen
weighted
hyperintense images,
relative
on both consistent
to the
Ti- and with
177
#{149} Number
3
ed
to determine
the
the diagnosis ASSC. U
and
role
of
imaging
treatment
in
6.
7.
8.
References River
CL,
Robbins
hemoglobin:
AB, Schwartz
a clinical
study.
SO. S-C Blood 1961;
18:385-416.
2.
3.
Fullerton WT, Hendrickse JP, Watson-Wilhams EJ. Hemoglobin SC disease in pregnancy. In: JonxisJHP, ed. Abnormal hemoglobins in Africa. Philadelphia: Davis, 1965; 411-433. Geola F, Kukreja SC, Schade SG. Splenic sequestration with sickle cell-C disease.
Arch 4.
5.
Intern
posplenism Am
J Hematol
9.
in hemoglobin 1985;
S-C disease.
CC, Castro 0. Acute crises in adults with Am J Med 1986; 80:985-
cell disease.
Bowcock
SJ,
Nwabueze
11.
12.
ED,
Cook
AE,
Aboud HH, Hughes RG. Fatal splenic soquestration in adult sickle cell disease. Clin Lab Haematol 1988; 10:95-99. Topley JM, Rogers DW, Stevens MCG, Serjeant CR. Acute splenic sequestration and hypersplenism in the first five years in homozygous sickle cell disease. Arch Dis Child 1981; 56:765-769. Williams WJ, Beutler E, Erslev AJ, Lichtman MA. Hematology. New York:
McGraw-Hill, 10.
Med 1978; 138:307-308.
Magid D, Fishman EK, Siegelman SS. Computed tomography of the spleen and liver in sickle cell disease. AJR 1984; 143:245-249. Sear DA, Udden MM. Splenic infarction, splenic sequestration, and functional hy-
DL, Kletter sequestration
990.
T2-
1.
Solanki splenic
sickle
of
hem-
orrhage. This was confirmed pathologically in one case, and in the other, a low-signal-intensity “hemosiderin ring” was highly suggestive of hemorrhage. Adler et a! (12) compared the appearance of the spleen in 13 patients with sickle cell disease with that of 60 healthy patients and found abnormally diminished splenic intensity relative to liver and paraspinal muscle on T2weighted images in all 13 patients. This finding was not seen in either of our patients, which may be due to the heterozygous, rather than homozygous, nature of their sickle cell disease. To our knowledge, there have been no reports of the usual MR appearance of
Volume
the spleen in patients with heterozygous sickle cell disease. In conclusion, further study is need-
1983.
Emond
AM,
Maude
GH, Serjeant
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Radiology
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