AJR 2000; 175:1145-1149
© American Roentgen Ray Society
MR Imaging of Complications After Liver Transplantation
Katsuyoshi Ito1,2,
Evan S. Siegelman1,
Alan H. Stolpen1 and
Donald G. Mitchell3
1
Department of Radiology, The Hospital of the University of Pennsylvania, 3400
Spruce St., 1st Floor, Silverstein, Philadelphia, PA 19104-4283.
2
Present address: Department of Radiology, Yamaguchi University School of
Medicine, 1-1-1 Minamikogushi, Ube, Yamaguchi 755-8505.
3
Department of Radiology, Thomas Jefferson University Hospital, 132 S. 10th
St., 1096 Main Bldg., Philadelphia, PA 19107.
Received January 3, 2000;
accepted after revision March 21, 2000.
Address correspondence to K. Ito.
Introduction
Liver transplantation has become a common treatment for end-stage liver
disease. Even with improvements in surgical techniques and immunosuppression
therapy, there are still a number of significant complications that can
develop after liver transplantation. Sonography is used as the initial imaging
technique for the detection of complications after liver transplantation.
However, current MR imaging techniques, including contrast-enhanced MR
angiography and MR cholangiography, may provide a more comprehensive
evaluation of the transplanted liver and reveal abnormalities of vascular
structures, bile ducts, and liver parenchyma and depict extrahepatic tissues.
We describe the imaging findings found after liver transplantation, including
common expected postoperative findings and various hepatobiliary
complications; we also discuss the role of MR imaging in the diagnosis of
complications after liver transplantation. The MR imaging techniques we
describe are similar to those described in referenced articles
[1,
2].
Normal Findings After Liver Transplantation
Familiarity with expected postoperative MR imaging findings of the
transplanted liver is essential for the evaluation of complications after
transplantation. A small amount of ascites or fluid in the perihepatic region
or the intersegmental fissure of the transplanted liver and transient
right-sided pleural effusion are common findings after liver transplantation
[3]
(Fig. 1). These fluid
collections usually resolve within weeks. Lymph nodes are frequently
identified in the porta hepatis and portacaval space and are often reactive.
However, posttransplantation lymphoproliferative disorder should be considered
when enlarged lymph nodes are detected 4-12 months after transplantation.
Periportal high signal intensity on T2-weighted MR images is seen with greater
frequency in patients with a shorter interval after transplantation
(Fig. 1). This finding may
persist for several weeks. Periportal abnormal high signal intensity is
related to lymphedema caused by the interruption of normal lymphatic drainage
by transplantation. Periportal high signal intensity does not correlate with
acute allograft rejection [4].
Narrowing of the portal vein at the porta hepatis, presumably caused by
surrounding edema, is a transient vascular change observed in the early
postoperative period. Mild anastomotic narrowing of the portal vein, caused by
the smaller caliber of the donor portion than the recipient portion, is also a
common finding after liver transplantation
(Fig. 2).
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Fig. 1. —52-year-old man who underwent successful liver transplantation.
T2-weighted axial fast spin-echo MR image (TR/TE, 8571/108) shows diffuse
periportal abnormal high signal intensity as periportal collar
(arrows). Note fluid collections (arrowheads) around liver
and spleen.
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Fig. 2. —51-year-old woman who underwent successful liver transplantation.
Maximum-intensity-projection image from three-dimensional contrast-enhanced MR
angiography (TR/TE, 6.2/1.1) shows anastomotic narrowing of portal vein
(arrow), presumably caused by smaller caliber of donor portion than
of recipient portion.
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Vascular Complications
Hepatic Artery Thrombosis
Hepatic artery thrombosis is the most common vascular complication of liver
transplantation, occurring in up to 12% of adult patients. Thrombosis is
associated with increased cold ischemia time of the donor liver, severe acute
rejection, anatomic variants of hepatic vasculature, and incongruence of the
joined vessels [5]. Thrombosis
of the hepatic artery results in bile duct ischemia and necrosis because the
hepatic artery is the sole vascular supply to the allograft biliary system.
Contrast-enhanced three-dimensional MR angiography is a useful and noninvasive
method for evaluating the patency of the hepatic artery, with accuracy similar
to that of sonography [1]
(Figs.
3,4,5A,5B,5C),
and has the potential to replace diagnostic hepatic angiography. Additionally,
contrast-enhanced MR angiography may play an important role in identifying
patients who require hepatic angiography with therapeutic options, including
thrombectomy, intraaterial thrombolytic therapy, or angioplasty.
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Fig. 3. —71-year-old man who underwent liver transplantation.
Maximum-intensity-projection image from three-dimensional contrast-enhanced MR
angiography (TR/TE, 6.2/1.1) shows normal hepatic artery (arrow)
originating from celiac trunk. Note superior mesenteric artery
(arrowhead).
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Fig. 4. —51-year-old woman with hepatic artery thrombosis after liver
transplantation. Maximum-intensity-projection image from three-dimensional
contrast-enhanced MR angiography (TR/TE, 6.2/1.1) shows complete obstruction
of common hepatic artery (arrow) 15 mm beyond its origin. Obstruction
likely corresponds to anastomosis. Note normal celiac trunk and splenic artery
and portal venous branches. Distal splenic vein was out of scan range.
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Fig. 5A. —42-year-old woman with hepatic artery thrombosis and hepatic
infarction after liver transplantation. Maximum-intensity-projection image
from three-dimensional contrast-enhanced MR angiography (TR/TE, 12/1.9) shows
proximal thrombosis of hepatic artery (long arrow). Note lack of
opacification of distal branches. Also note gastroduodenal artery (short
arrow). Superior mesenteric artery is normal (arrowhead).
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Fig. 5B. —42-year-old woman with hepatic artery thrombosis and hepatic
infarction after liver transplantation. T2-weighted axial fast spin-echo MR
image (4050/80) shows heterogeneous high signal intensity (arrows) in
left and right hepatic lobes.
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Fig. 5C. —42-year-old woman with hepatic artery thrombosis and hepatic
infarction after liver transplantation. Contrast-enhanced T1-weighted
gradient-echo MR image (130/2.5) shows no enhancement of areas
(arrows) seen in B, indicating hepatic infarction caused by
hepatic artery thrombosis. Liver infarction was pathologically confirmed
during second liver transplantation.
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Portal Vein Thrombosis or Stenosis
Portal vein thrombosis is an uncommon complication, observed in fewer than
12% of patients. Portal vein stenosis is also uncommon, usually occurring at
the anastomosis, and may be asymptomatic or cause symptoms of portal
hypertension. Contrast-enhanced MR angiography can provide excellent
visualization of portal vein thrombosis and stenosis
[1] (Figs.
6 and
7) and can facilitate
distinction of thrombosis from slow flow. Treatment of symptomatic portal vein
thrombosis or stenosis may include thrombectomy, segmental portal vein
resection, percutaneous thrombolysis and stent placement, or balloon
angioplasty.
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Fig. 6. —61-year-old woman with portal vein thrombosis after liver
transplantation. Contrast-enhanced gradient-echo MR image (TR/TE, 260/1.5)
shows filling defect in portal vein (arrow) caused by thrombus.
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Fig. 7. —52-year-old man with portal vein stenosis after liver
transplantation. Maximum-intensity-projection image from three-dimensional
contrast-enhanced MR angiography (TR/TE, 6.2/1.1) reveals stenosis of portal
vein at anastomosis (arrow). Note wedge-shaped hyperintensity region
in dome of liver caused by arterioportal shunt.
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Inferior Vena Cava Thrombosis
Inferior vena cava thrombosis is rare, occurring in fewer than 3% of
patients. It is caused by technical problems or compression of vessels by a
fluid collection [3].
Flow-sensitive gradient-echo MR imaging (i.e., time of flight or phase
contrast) and contrast-enhanced MR angiography can be used to evaluate the
inferior vena cava. Inferior vena cava thrombus is depicted as an intraluminal
defect. Coronal scanning is useful for determining the extent of inferior vena
cava thrombus (Fig.
8A,8B).
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Fig. 8A. —53-year-old man with partial inferior vena cava thrombosis after
liver transplantation. Flow-sensitive axial gradient-echo MR image (TR/TE,
34/3.1) shows signal defects (arrow) in inferior vena cava indicating
presence of thrombus. Inferior vena cava is not completely obstructed.
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Fig. 8B. —53-year-old man with partial inferior vena cava thrombosis after
liver transplantation. Flow-sensitive coronal gradient-echo MR image (51/5.3)
shows similar findings. Extension of thrombosis (arrow) is seen in
coronal plane.
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Biliary Tract Complications
Biliary Strictures
Most biliary strictures occur at the anastomotic site and may be caused by
scar formation that results in retraction and narrowing. Nonanastomotic
strictures are probably caused by bile duct ischemia resulting from arterial
insufficiency. They occur at the hepatic hilum and progress peripherally into
the intrahepatic bile ducts. MR cholangiography can be used to screen for
biliary strictures [2] (Fig.
9A,9B,9C).
Percutaneous transhepatic cholangiography can be performed for initial
treatment, including balloon dilation, drainage, and stent placement; however,
surgical reconstruction or retransplantation may be required.
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Fig. 9A. —39-year-old woman with biliary stricture after liver
transplantation. Two consecutive T2-weighted axial fast spin-echo MR images
(TR/TE, 9230/100) show stricture of distal bile duct (arrow,
B) with proximal ductal dilatation (arrow, A) in
patient with choledochocholedochostomy reconstruction. Note slightly dilated
intrahepatic bile duct in lateral segment (arrowhead, A).
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Fig. 9B. —39-year-old woman with biliary stricture after liver
transplantation. Two consecutive T2-weighted axial fast spin-echo MR images
(TR/TE, 9230/100) show stricture of distal bile duct (arrow,
B) with proximal ductal dilatation (arrow, A) in
patient with choledochocholedochostomy reconstruction. Note slightly dilated
intrahepatic bile duct in lateral segment (arrowhead, A).
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Bile Leakage
Bile leakage is often a serious complication that develops after
transplantation. Leaks at the biliary anastomosis are common; however, a bile
leak may be caused by bile duct necrosis in patients with hepatic artery
occlusion, producing bilomas or bile peritonitis.
Mucocele of Bile Duct Remnant
Cystic duct remnant mucocele is an uncommon complication that occurs when
the donor cystic duct remnant becomes distended with mucus. It may compress
and obstruct the common hepatic duct, in which case surgical or interventional
procedures may be necessary for treatment. Dilatation of a recipient's
extrahepatic duct remnant after choledochojejunostomy may develop, possibly
caused by Oddi's sphincter dysfunction. These abnormalities are readily seen
as cystic structures on MR cholangiographic sequences
(Fig. 10).
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Fig. 10. —40-year-old man with mucocele of cystic duct remnant after liver
transplantation. T2-weighted coronal single-shot fast spin-echo MR image
(TR/TE, infinite/97) shows dilated cystic duct remnant (arrow)
adjacent to common bile duct.
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Hepatic Parenchymal Complications
Hepatic Infarction or Necrosis
Extrahepatic arterial supply (e.g., parabiliary arteries), which is present
in native livers, is disrupted after transplantation. Therefore, when the
transplanted hepatic artery blood supply is insufficient, bile duct necrosis
develops leading to hepatic parenchymal infarction. Infarctions are commonly
revealed on MR images as peripheral or central lesions with wedge-shaped or
round appearances and no contrast enhancement (Fig.
5A,5B,5C);
however, occasionally, some infarctions appear as periportal irregular
lesions.
Hepatic Abscess or Biloma
Hepatic artery insufficiency caused by thrombosis may induce bile duct
necrosis that may lead to bilomas or abscesses. Although the differentiation
between biloma and abscess is often difficult, intrahepatic bilomas caused by
bile duct necrosis are rather irregular initially without an enhancing margin;
abscesses have an irregular, thick wall (Fig.
11A,11B)
and often develop in the infarcted lobe.
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Fig. 11A. —35-year-old man with hepatic abscess caused by Klebsiella
pneumoniae after liver transplantation. T1-weighted axial spin-echo MR
image (TR/TE, 350/8) shows hypointense mass with thick wall (arrow)
in left hepatic lobe.
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Fig. 11B. —35-year-old man with hepatic abscess caused by Klebsiella
pneumoniae after liver transplantation. Contrast-enhanced axial
gradient-echo MR image (120/1.4) shows mass as hypointense area with enhanced
thick wall (arrow). Diagnosis of abscess was confirmed by
percutaneous drainage.
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Recurrence of Malignant Tumor
In patients with end-stage cirrhosis and known or occult hepatocellular
carcinoma, recurrent hepatocellular carcinoma is a serious complication that
develops after transplantation. The most common site of recurrent
hepatocellular carcinoma is the lung, followed by the liver allograft, then
the regional or distant lymphatic system
[6]. Recurrent hepatocellular
carcinoma in the liver allograft appears as a hypervascular nodule on
contrast-enhanced dynamic MR images (Fig.
12). Lung metastases are presumably caused by embolization of
tumor cells via the hepatic veins before or during transplantation,
potentiated by postoperative immunosuppression therapy. Evaluation of
recurrent hepatocellular carcinoma after transplantation is important to
facilitate the early detection of resectable isolated tumors and the prompt
institution of adjuvant chemotherapy.
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Fig. 12. —44-year-old woman with recurrent hepatocellular carcinoma after
liver transplantation. Contrast-enhanced axial gradient-echo MR image (TR/TE,
115/2.2) obtained during arterial phase shows early enhancing nodules
(arrows) in right hepatic lobe, indicating recurrent hepatocellular
carcinoma.
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Other Complications
Right-Sided Adrenal Hemorrhage
Right-sided adrenal gland hemorrhage has been reported in both adult
pediatric patients after liver transplantation
[7]. There are two causes of
right-sided adrenal gland hemorrhage: venous engorgement caused by right-sided
adrenal vein ligation during the removal of a portion of the inferior vena
cava during transplantation, or coagulopathy caused by a patient's preexisting
liver dysfunction. Adrenal hematoma appears as a suprarenal mass on MR images.
MR imaging is useful in the diagnosis of adrenal gland hemorrhage because of
typical findings of heterogeneous high signal intensity on T1-weighted MR
images caused by the paramagnetic effects of methemoglobin in subacute blood
(Fig. 13). Subhepatic
hematoma, typically located laterally to the adrenal gland, is a common
postoperative finding and should be included in the differential
diagnosis.
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Fig. 13. —44-year-old woman with adrenal gland hemorrhage after liver
transplantation. T1-weighted axial gradient-echo MR image (TR/TE, 100/1.5)
depicts right-sided adrenal gland hematoma that shows peripheral high signal
intensity with central low signal intensity (arrow). Note
intrahepatic bile duct dilatation.
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Posttransplantation Lymphoproliferative Disorder
Organ transplant patients who undergo immunosuppressive therapy are at risk
for posttransplantation lymphoproliferative disorder (Fig.
14A,14B).
Factors supporting the diagnosis of this disorder include symptoms that
develop 4-12 months after transplantation and serologic evidence of exposure
to the Epstein-Barr virus [8].
However, core biopsies should be performed for accurate diagnosis and prompt
treatment. Common features of posttransplantation lymphoproliferative disorder
are lymph node enlargement and extranodal involvement, including involvement
of the spleen, liver, small bowel, kidney, mesentery, and adrenal glands
[9].
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Fig. 14A. —57-year-old woman with posttransplantation lymphoproliferative
disorder. T1-weighted axial gradient-echo MR image (TR/TE, 150/1.5) shows
extrahepatic soft-tissue mass adjacent to lower edge of right hepatic lobe
(arrow).
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Fig. 14B. —57-year-old woman with posttransplantation lymphoproliferative
disorder. Contrast-enhanced axial gradient-echo MR image (150/1.5) shows mass
with rim enhancement (arrow). Pathologic diagnosis of lymphoma was
confirmed by biopsy.
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References
-
Stafford-Johnson DB, Hamilton BH, Dong Q, et al. Vascular
complications of liver transplantation: evaluation with gadolinium-enhanced MR
angiography. Radiology
1998;207:153
-160[Abstract/Free Full Text]
-
Fulcher AS, Turner MA. Orthotopic liver transplantation: evaluation
with MR cholangiography. Radiology
1999;211:715
-722[Abstract/Free Full Text]
-
Bowen A, Hungate GR, Kaye RD, Reyes J, Towbin RB. Imaging in liver
transplantation. Radiol Clin North Am
1996;34:757
-778[Medline]
-
Lang P, Schnarkowski P, Grampp S, et al. Liver transplantation:
significance of the periportal collar on MRI. J Comput Assist
Tomogr 1995;19:580
-585[Medline]
-
Legmann P, Costes V, Tudoret L, et al. Hepatic artery thrombosis
after liver transplantation: diagnosis with spiral CT.
AJR
1995;164:97
-101[Abstract/Free Full Text]
-
Ferris JV, Baron RL, Marsh JWJ, Oliver JH III, Carr BI, Dodd GD
III. Recurrent hepatocellular carcinoma after liver transplantation: spectrum
of CT findings and recurrence patterns. Radiology
1996;198:233
-238[Abstract/Free Full Text]
-
Bowen A, Keslar P, Newman B, Hashida Y. Adrenal hemorrhage after
liver transplantation. Radiology
1990;176:85
-88[Abstract/Free Full Text]
-
Strouse PJ, Platt JF, Francis IR, Bree RL. Tumorous intrahepatic
lymphoproliferative disorder in transplanted livers.
AJR
1996;167:1159
-1162[Abstract/Free Full Text]
-
Pickhardt PJ, Siegel MJ. Posttransplantation lymphoproliferative
disorder of the abdomen: CT evaluation in 51 patients.
Radiology
1999;213:73
-78[Abstract/Free Full Text]
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Introduction
Normal Findings After Liver...
