Canadian Association of Radiologists Journal 64 (2013) 18e27www.carjonline.org
Abdominal Imaging / Imagerie abdominale
Abdominal Hemangiomas: A Pictorial Review of Unusual,Atypical, and Rare Types
Vijayanadh Ojili, MDa,*, Sree Harsha Tirumani, MDb, Gowthaman Gunabushanam, MDc,Arpit Nagar, MDd, Venkateswar Rao Surabhi, MDe, Kedar N. Chintapalli, MDa,
John Ryan, MD, FRCPCb
aDepartment of Radiology, University of Texas Health Science Center at San Antonio, San Antonio, Texas, USAbDiagnostic Imaging, The Ottawa Hospital, Ottawa, Ontario, Canada
cDiagnostic Radiology, Yale University School of Medicine, New Haven, Connecticut, USAdDivision of Abdominal Imaging, Department of Radiology, Ohio State University Medical Center, Columbus, Ohio, USA
eDepartment of Radiology, University of Texas Health Science Center at Houston, Houston, Texas, USA
Abstract
Hemangiomas are a radiologist’s dream lesions because they allow a confident diagnosis most of the time. However, within the abdomen,hemangiomas may occur in such atypical locations and can have such unusual features that they cause significant diagnostic dilemma andmay end up being excised surgically. The literature is replete with isolated case reports of atypical hemangiomas in the abdominal cavity, and,to our knowledge, so far, there is no comprehensive review. We present, in this article, a pictorial review of a gamut of uncommonhemangiomas and hemangiomatosis syndromes. Knowledge of these rare types can help in limiting diagnostic errors and increase theconfidence of radiologists, thus avoiding unnecessary surgeries.
R�esum�e
Les h�emangiomes sont les l�esions qui posent le moins de difficult�es aux radiologistes, leur permettant de poser un diagnostic sur la plupartdu temps. Toutefois, les h�emangiomes localis�es dans l’abdomen se trouvent parfois �a des endroits atypiques et peuvent pr�esenter des car-act�eristiques inhabituelles qui compliquent grandement le diagnostic et peuvent n�ecessiter une ablation chirurgicale. La litt�erature pr�esente detr�es nombreux cas d’h�emangiomes atypiques dans la cavit�e abdominale, mais, �a notre connaissance, aucune �etude exhaustive n’a �et�e r�ealis�eejusqu’ici. Dans cet article, nous faisons une revue iconographique de divers cas d’h�emangiomes inhabituels et de syndromes associ�es auxh�emangiomes. Les donn�ees sur ces formes rares d’h�emangiomes peuvent contribuer �a la diminution des erreurs de diagnostic et amener lesradiologistes �a poser leur diagnostic avec une certitude accrue, ce qui permet aussi d’�eviter des chirurgies inutiles.� 2013 Canadian Association of Radiologists. All rights reserved.
Key Words: Hemangioma; Abdomen; Ultrasound; Computed tomography; Magnetic resonance imaging
Hemangiomas are ubiquitous vascular neoplasms thatmay be found in virtually every human organ. They arebenign tumours that arise from embryonic remnants of uni-potent angioblastic cells [1]. Although hemangiomas mayoccur anywhere within the abdomen, including the solidorgans, hollow viscera, ligaments, and abdominal wall, theliver is the most common site. Typically, hemangiomas have
* Address for correspondence: Vijayanadh Ojili, MD, Department of
Radiology, University of Texas Health Science Center at San Antonio, 7703
Floyd Curl Drive MS 7800, San Antonio, Texas 78229, USA.
E-mail address: [email protected] (V. Ojili).
0846-5371/$ - see front matter � 2013 Canadian Association of Radiologists. A
doi:10.1016/j.carj.2011.08.004
a pathognomonic imaging appearance. However, unusualimaging features and atypical locations can present signifi-cant diagnostic dilemmas. The literature is replete with casereports of unusual and atypical hemangiomas that resulted insurgical excision, with the diagnosis established only athistopathology. In this article, we present a pictorial reviewof a gamut of uncommon hemangiomas and hemangioma-tosis syndromes. Knowledge of these rare types can help inlimiting diagnostic errors and increase the confidence ofradiologists, thus avoiding unnecessary surgeries. In most ofthe cases, magnetic resonance imaging (MRI) is the modalityof choice and is a problem-solving tool.
ll rights reserved.
Figure 1. Atypical sclerosing hepatic hemangioma. (A, B) Axial contrast computed tomography image of the liver in the portal venous phase, showing an
irregular hypodense tumour (arrows), with heterogenous enhancement and central calcification. Biopsy of the lesion showed cavernous hemangioma.
19Review of abdominal hemangiomas / Canadian Association of Radiologists Journal 64 (2013) 18e27
Hepatic Hemangiomas
Hepatic hemangiomas have a prevalence of 1%-20% inthe general population and are 2-5 times more common inwomen [2]. They are often asymptomatic, incidentallydetected, and require no treatment. Symptomatic hemangi-omas are usually large and present clinically with pressuresymptoms, rupture, or consumptive coagulopathy. On ultra-sound, a typical hepatic hemangioma is well defined; smallerthan 3 cm in size; and hyperechoic, with posterior acousticenhancement. Blood-filled sinuses of a hemangioma havelow acoustic impedance, which causes posterior acousticenhancement due to increased through-transmission [3]. On
Figure 2. Giant multiloculated hepatic hemangioma. (A-C) Axial postcontrast T
minute delayed (C) phases, showing large septated hypointense lesion (asterisks
dynamic computed tomography (CT), hemangiomas arewell-marginated hypodense lesions with peripheral nodularenhancement that matches the aorta in arterial phase,progressive centripetal filling on venous phase, and persistentenhancement on delayed images. A high signal on T2-weighted images, which increases further on heavily T2-weighted sequences, is due to the very long T2 relaxationtime. Postgadolinium MRIs are similar to iodinated contraston CT. MRI has a sensitivity and specificity close to 98% andaccuracy of 99% in characterizing hemangioma [4]. Ontechnetium 99m pertechnetateelabeled red blood cell scin-tigraphy, hemangiomas show increased activity on delayedblood pool images.
1-weighted magnetic resonance images in arterial (A), venous (B), and 2-
) with nodular (white arrows) enhancing septae.
Figure 3. Splenic hemangioma. (A) Ultrasound image of the spleen, showing a well-marginated hyperechoic tumour (asterisk). (B) Axial contrast computed
tomography image, showing heterogenous enhancing lesion in the portal venous phase (asterisk).
20 V. Ojili et al. / Canadian Association of Radiologists Journal 64 (2013) 18e27
Various atypical patterns of hemangiomas have beendescribed and include hemangiomas with echogenic border;giant hemangiomas; flash filling, calcified (Figure 1), hyali-nized, cystic, or multilocular hemangiomas; pedunculatedhemangiomas; and hemangiomas with fluid-fluid levels [5].Giant hemangiomas are larger than 4 cm and can becomplicated by rupture, intratumoural hemorrhage, eryth-rocytosis due to erythropoietin secretion, or consumptivecoagulopathy (Figure 2) [6]. Such hemangiomas may needsurgical excision or partial hepatectomy. Hemangiomas canoccasionally be associated with arterioportal shunting,capsular retraction, and nodular hyperplasia [7].
Splenic Hemangiomas
Hemangioma of the spleen, although very uncommon, is themost common primary splenic neoplasm. These usually aresmaller than 2 cm, however, they may occasionally attaina massive size and present clinically with mass effect, pain, orhemorrhage. They are either single or multiple, and associatedwith systemic hemangiomatosis. Splenic hemangiomas onultrasound appear well marginated, echogenic, and, whenlarge, heterogenous with anechoic areas (Figure 3A). Dopplerultrasoundmay show peripheral vascularity. CT characteristics
Figure 4. Splenic hemangioma. (A, B) Axial dynamic contrast-enhanced T1-we
phases, showing a hypointense splenic lesion with progressive centripetal filing
typical of hemangioma are peripheral nodular enhancementand progressive centripetal filling, with larger lesions fillingmore inhomogenously (Figure 3B). T2 hyperintensity, again, issuggestive but not diagnostic because metastasis, lymphoma,and abscess, the common differentials for splenic lesions, showsimilar signal. Signal matching the cerebrospinal fluid or bileand centripetal filling on gadolinium-enhanced images arerelatively specific for hemangioma (Figure 4) [8]. Nuclear scanwith labeled red blood cells shows slow filling and slowwashout, whereas sulfur colloid scan shows hemangiomas asphotopenic areas. Treatment is indicated for giant hemangi-omas with a risk of rupture and consists of partial or totalsplenectomy. The risk of malignant transformation is onlytheoretical [9].
Gastrointestinal Hemangiomas
Hemangiomas can occur anywhere in the gastrointestinaltract, with the small intestine being the most common site,followed by the large intestine and the stomach [10]. Theyconstitute up to 10% of all benign small intestine tumours and1.6% of benign gastric tumours [10]. Jejunum is the commonsite in small bowel and rectosigmoid in large bowel [11].Clinically, they present with chronic gastrointestinal bleeding,
ighted magnetic resonance images in venous (A) and 5-minute delayed (B)
(arrows). Note the incidental hepatic cysts (asterisks).
Figure 5. Gastric hemangioma in 2 different patients. (A, B) Axial contrast-enhanced computed tomography (CT) images in arterial (A) and venous (B) phase,
showing circumferential thickening of body of the stomach (asterisks) with progressive enhancement. (C) Axial contrast-enhanced CT image of another patient
in the venous phase, showing a large exophytic tumour with nodular enhancement arising from the gastric wall (asterisk).
Figure 6. Renal hemangioma in 2 different patients. (A, B) Axial contrast computed tomography (CT) images in arterial (A) and venous (B) phases, showing
a peripheral nodular enhancing tumour (arrowheads) arising from the renal papilla. (C) Coronal reformatted CT image of another patient in late arterial phase,
showing a large enhancing tumour with phleboliths (asterisk) filling the renal pelvis.
21Review of abdominal hemangiomas / Canadian Association of Radiologists Journal 64 (2013) 18e27
Figure 7. Perirenal hemangioma. (A, B) Axial contrast computed tomography (CT) images in the portal venous phase, demonstrating an enhancing tumour
(asterisks), with phleboliths in relation to the upper pole of the right kidney. (C, D) Coronal and sagittal reformatted CT images, showing the tumour (asterisks)
separate from the normal right adrenal gland (arrows).
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mechanical obstruction, perforation, or intussusception.Gastrointestinal hemangiomas can be associated with heman-giomas of solid organs and hemangiomatosis syndromes. Onradiologic examination, the presence of phleboliths is patho-gnomonic [11]. Diffuse wall thickening (Figure 5, A and B),polypoidal intraluminal mass, exophytic mass (Figure 5C),mucosal irregularities, and a mesenteric mass that involvesadjacent bowel loops are findings seen on cross-sectionalimaging. A change of position of phleboliths and theabsence of rigidity are reported as pathognomonic of gastrichemangiomas [12]. MRI shows a typical high signal on T2-weighted imaging and after gadolinium enhancement [11].
Adrenal Hemangioma
Cavernous hemangiomas of the adrenal gland are very rare,with only 52 cases being reported so far [13]. Often detectedincidentally on routine imaging, they may present withnonspecific abdominal pain, dragging sensation, or mass inthe abdomen. Intra-abdominal hemorrhage, although rare, canbe life threatening, with the risk higher with tumours largerthan 3.5 cm [14]. On radiologic examination, hemangiomasare difficult to distinguish from the more common adrenalneoplasms. They usually are unilateral, and up to 60% showspeckled calcification on radiographs [14]. Ultrasound
features are nonspecific. Findings on CT, which can favora hemangioma, are similar to hemangiomas elsewhere andinclude a peripheral high-density rim and patchy and spottyperipheral enhancement with centripetal filling [15]. MRIshows high signal intensity on a T2-weighted sequence andlow signal, with areas of high signal on T1-weighted imagesthat correspond to areas of hemorrhage [15]. Surgical excisionis considered for symptomatic tumours and tumours at risk ofcomplications, such as hemorrhage, thrombosis, and necrosis.
Renal and Perirenal Hemangiomas
Genitourinary hemangiomas are uncommon and may arisefrom the kidneys, lower urinary tract, or reproductive organs.The kidney is the most common site, followed by the urinarybladder [16]. Within the kidney, the most common site is therenal papilla (Figure 6) [16]. Perirenal hemangiomas alsohave been reported (Figure 7) [17]. Renal hemangiomasusually are small and asymptomatic, but, when large, canpresent as flank mass, with life-threatening hematuria andrarely renal vein thrombosis. Ultrasound shows hemangiomato be a hyperechoic, or rarely, a hypoechoic lesion. CT showshemangioma as a hypodense mass or a heterogenousenhancing solid mass, depending on cavernous or capillaryhistology and the presence or absence of hemorrhage [18].
Figure 8. Gastrosplenic ligament Hemangioma. (A, B) Axial contrast computed tomography in venous (A) and delayed (B) phases, showing a well-defined
hypodense lesion (asterisks) in the gastrosplenic ligament with nodular enhancement. (C) Coronal true fast imaging with steady state precession magnetic
resonance image (MRI), showing the tumour to be a T2 hyperintense tumour (asterisk). (D) Axial contrast-enhanced T1-weighted MRI in venous phase,
showing nodular enhancement in the tumour (asterisk).
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MRI can be diagnostic, with a typical high signal onT2-weighted images, with flow voids. The presence ofhemorrhage or necrosis results in T2 hypointensity [18]. Adifferential diagnosis includes papillary necrosis, renal cellcarcinoma, urothelial tumours, ectopic papilla, and hemor-rhagic papillitis.
Hemangiomas of the Mesentery, Omentum,Retroperitoneum, and Body Wall
Although uncommon, hemangiomas can occur in theomentum and mesentery because these are derivatives ofmesodermal remnants. Isolated case reports in the literaturedescribe their radiologic features. Reported sites of origininclude omentum, gastrosplenic ligament, lesser omentum,and mesoappendix. Nonspecific symptoms were associatedwith these hemangiomas, although a few reports mentionacute abdomen due to rupture and infection. Ultrasound andCT reveal a solid mass with a nodular appearance (Figure 8).MRI can be a problem-solving tool, with typical imaging
characters of hemangioma (Figure 8). Extensive mobility ofmesenteric hemangioma has been reported [19]. Retroperi-toneal hemangiomas are of the cavernous type and are diffi-cult to diagnose before surgery (Figure 9). They can occur inperirenal, peripancreatic, or periureteric locations, and in theiliopsoas muscles (Figure 10) [17]. They may be adherent tothe pancreatic head, kidney, ureter, peritoneum, or muscles,which makes surgical excision difficult. They have the sameimaging features as hemangiomas in other locations, again,with MRI being the definitive diagnostic modality [20].Hemangioma also can occur within the inferior vena cava(Figure 11). Hemangiomas of the abdominal wall can beisolated or associated with intra-abdominal vascular malfor-mations (Figure 12). Very rarely, hemangiomas can occur inthe inguinal canal along the spermatic cord (Figure 13) [21].
Hemangiomatosis Syndromes
These are the rare diverse syndromes with vascular mal-formations as the hallmark pathology. A few well-known
Figure 9. Retroperitoneal hemangioma. (A) Axial unenhanced computed tomography (CT) sections, showing a well-defined lesion (arrow) adjacent to the
inferior vena cava. (B, C) Axial contrast-enhanced CT images in arterial and venous phases, showing peripheral enhancement and progressive central filling
(arrows).
24 V. Ojili et al. / Canadian Association of Radiologists Journal 64 (2013) 18e27
syndromes include Klippel-Tr�enaunay syndrome, Kasabach-Merritt syndrome, blue rubber bleb nevus syndrome, andProteus syndrome. Klippel-Tr�enaunay syndrome is charac-terized by port-wine stain, abnormal venous structures, andosseous and soft-tissue hypertrophy [22,23]. Sixty-threepercent of patients have all 3 components of the abovetriad hypertrophy [22]. Varicose veins are seen in mostpatients. Cavernous hemangiomas are seen in solid
Figure 10. Psoas muscle hemangioma. (A) Axial nonefat-saturated T1-weighted m
lesion in the left psoas (arrow). (B) Axial T2-weighted MRI, showing the lesion
abdominal viscera, retroperitoneum, and mediastinum(Figure 14, A-D). Gastrointestinal tract involvement is seenin 20% of patients; the distal colon and rectum are the mostcommon sites (Figure 14, C and D). There can be intra-abdominal and intrapelvic extension, and involvement ofgenitalia [24]. Imaging features are generally characteristic.Plain radiography and CT demonstrate phleboliths. Dopplerultrasound allows evaluation of venous anomalies. MRI and
agnetic resonance images (MRI), demonstrating a well-defined hyperintense
to be hyperintense (arrow).
Figure 11. Hemangioma of the inferior vena cava (IVC). (A) Ultrasound image of intrahepatic IVC, showing a well-defined echogenic lesion in the wall
(arrow). (B) Coronal reformatted contrast computed tomography image, showing the lesion as a filling defect in IVC with mild enhancement (arrow). (C, D)
Axial T2-weighted and postcontrast T1-weighted magnetic resonance images, showing a hyperintense lesion with enhancement (arrows).
25Review of abdominal hemangiomas / Canadian Association of Radiologists Journal 64 (2013) 18e27
magnetic resonance venography can be used to evaluate deepmalformations, including abdominal viscera and colon(Figure 14E). Venous malformations of Klippel-Tr�enaunaysyndrome are hyperintense on T2-weighted images and showno flow voids [24]. Kasabach-Merritt syndrome is a raremanifestation of large hemangiomas (Figure 15). It is char-acterized by intralesional fibrinolysis, consumptive coagul-opathy, and thrombocytopenia, sometimes resulting indisseminated intravascular coagulation [25]. Neonatal
Figure 12. Hemangioma of abdominal wall. Axial computed tomography
image in the arterial phase, showing serpiginous vascular channels (arrow) in
the left lateral abdominal wall.
hemangiomatosis can result in this syndrome, with conges-tive heart failure and gastrointestinal bleeding [24]. Bluerubber bleb nevus syndrome is characterized by cutaneousand gastrointestinal venous malformations [24]. Proteussyndrome is characterized by vascular malformations,lipomas and fatty hypertrophy, regional atrophy, hyperpig-mentation, and nevi [26].
Figure 13. Inguinal canal hemangioma. Axial contrast-enhanced computed
tomography sections of pelvis, showing enhancing irregular soft-tissue
lesion (arrow) with phleboliths along the spermatic cord.
Figure 14. Klippel-Tr�enaunay syndrome. (A) Ultrasound image of the spleen, showing multiple hyperechoic lesions (white arrows) in the spleen, which
represent hemangiomas. (B, C) Axial and (D) coronal reformatted contrast computed tomography images, showing hemangiomas in the liver (long white
arrows), spleen (black arrow heads), left adrenal gland (black arrow), and right upper thigh (white arrow head). Thickened rectosigmoid with phleboliths (small
white arrows) represents colorectal hemangiomatosis. (E) Axial true fast imaging with steady-state precession magnetic resonance images show T2 hyper-
intense hemangiomas in the liver (thick white arrows), left adrenal gland (thin white arrow), and spleen (black arrow heads).
26 V. Ojili et al. / Canadian Association of Radiologists Journal 64 (2013) 18e27
Conclusion
Hemangiomas, although common and not life threatening,can be clinically and radiologically challenging when atyp-ical in imaging appearance and location. A high index of
Figure 15. Giant hepatic hemangioma causing Kasabach-Meritt syndrome. (A, B)
phases, showing a large nodular enhancing lesion (arrows), replacing almost the
radiologic suspicion and knowledge of atypical imagingfeatures may aid in the appropriate diagnosis of these enti-ties. Most hemangiomas have typical nodular enhancementand progressive filling. Therefore, dynamic imaging witheither CT or MRI is immensely advantageous over single-
Axial contrast-enhanced computed tomography images in arterial and venous
entire right lobe of liver. The patient developed consumptive coagulopathy.
27Review of abdominal hemangiomas / Canadian Association of Radiologists Journal 64 (2013) 18e27
phase imaging. Large hemangiomas may be associated withthrombosis, sclerosis, and calcification, and may becomplicated by rupture. The interpreting radiologist shouldlook for these findings and appropriately aid the referringclinician in the management of these patients.
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