Diagnostic Ultrasound - Abdomen and Pelvis

Hepatic Cavernous Hemangioma
Diagnoses: Liver
Nuclear Medicine Findings
• Tc-99m-labeled red blood cell scan with SPECT (95%
accuracy)
○ Early dynamic scan: Focal defect or less uptake
○ Delayed scans (over 30-50 min): Persistent filling
Imaging Recommendations
• Best imaging tool
○ In absence of risk factors, US for diagnosis and follow-up
(cost-effective plus radiation-free)
○ For definitive characterization, MR may be more
diagnostic than CT
• Protocol advice
○ Atypical lesions or lesions in high-risk patients may
require CT/MR or biopsy
DIFFERENTIAL DIAGNOSIS
Hepatocellular Carcinoma (HCC)
• Background cirrhosis or underlying liver disease
• Heterogeneous and usually hypoechoic
• Irregular or infiltrating borders
Hypervascular Metastases
• Usually multiple
• May have hypoechoic halo ("target" lesion)
Steatosis
• Geographic borders
• Vessels pass through lesion without distortion
Angiosarcoma
• Ill-defined and multicentric
• Highly aggressive, rapidly growing
PATHOLOGY
General Features
• Etiology
○ Hemangiomas occur sporadically without predisposing
factors
• Associated abnormalities
○ Associated with focal nodular hyperplasia (FNH)
○ Kasabach-Merritt syndrome
– Hemangioma with intravascular coagulation, clotting,
and fibrinolysis resulting in thrombocytopenia
Gross Pathologic & Surgical Features
• Solitary, well-defined, blood-filled, soft nodule
○ Size ranges from 2-20 cm
• Cut section: Giant hemangioma
○ Areas of fibrosis, necrosis, and cystic spaces
Microscopic Features
• Large vascular channels lined by single layer of endothelial
cells supported by thin fibrous septa
• No bile ducts or hepatocytes
• Thrombosis of vascular channels resulting in fibrosis and
calcification
CLINICAL ISSUES
Presentation
• Most common signs/symptoms
○ Small and typical hemangioma
– Usually asymptomatic
– Commonly seen on routine examination & autopsy
○ Giant hemangioma
– Asymptomatic or hepatomegaly/abdominal pain
• Lab data: Normal liver function tests
• Diagnosis
○ Multiphasic CECT, CEMR, or RBC scan with SPECT
imaging are highly diagnostic
Demographics
• Age
○ All age groups (uncommon in children)
○ More common in postmenopausal age group
• Gender
○ M:F = 1:2-1:5
• Epidemiology
○ Incidence
– 5-20% of population
– Increases with multiparity
○ Prevalence: Uniform worldwide
Natural History & Prognosis
• Most often asymptomatic; complications are rare
○ Spontaneous rupture, coagulation, or inflammation
○ Compression of adjacent structures
• Often show slow growth
Treatment
• Asymptomatic: Usually ignore
• Symptomatic large lesions: Surgical resection
DIAGNOSTIC CHECKLIST
Consider
• Small HCC or metastasis can mimic hemangioma
Image Interpretation Pearls
• Hemangioma may vary in echogenicity at different times of
scanning due to rate of blood flow within lesion
• May see posterior acoustic enhancement
SELECTED REFERENCES
1. Quaia E: The real capabilities of contrast-enhanced ultrasound in the
characterization of solid focal liver lesions. Eur Radiol. 21(3):457-62, 2011
2. Wakui N et al: Diagnosis of hepatic hemangioma by parametric imaging
using sonazoid-enhanced US. Hepatogastroenterology. 58(110-111):1431-5,
2011
3. Kamaya A et al: Hypervascular liver lesions. Semin Ultrasound CT MR.
30(5):387-407, 2009
4. Jang HJ et al: Hepatic hemangioma: atypical appearances on CT, MR
imaging, and sonography. AJR Am J Roentgenol. 180(1):135-41, 2003
5. Perkins AB et al: Color and power Doppler sonography of liver
hemangiomas: a dream unfulfilled? J Clin Ultrasound. 28(4):159-65, 2000
6. Vilgrain V et al: Imaging of atypical hemangiomas of the liver with pathologic
correlation. RadioGraphics. 20: 379-97, 2000
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