Diagnostic Ultrasound - Abdomen and Pelvis

Hepatic Cavernous Hemangioma
TERMINOLOGY
Synonyms
• Liver hemangioma, capillary hemangioma, cavernous
hemangioma
Definitions
• Benign tumor composed of dilated endothelial-lined
vascular channels lined by single layer of endothelial cells
supported by thin fibrous stroma
IMAGING
General Features
• Best diagnostic clue
○ Well-defined, uniformly hyperechoic mass
• Size
○ Small (capillary) hemangioma: < 2 cm
○ Typical hemangioma: 2-10 cm
○ Giant hemangioma: > 10 cm (arbitrary cutoff)
• Morphology
○ Most common benign tumor of liver
○ 2nd most common liver tumor after metastases
○ Usually solitary & grow minimally
○ May be multiple in up to 10% of cases
○ More commonly seen in postmenopausal women
○ May have central scar in giant hemangiomas
– Calcification of scar is rare (< 10%)
Ultrasonographic Findings
• Grayscale ultrasound
○ Typically homogeneously hyperechoic (over 2/3 of
patients)
– Probably due to slow blood flow rather than multiple
interfaces
– Smooth or lobulated well-defined borders
– Occasionally see posterior acoustic enhancement
○ Echogenicity may vary
– Echogenicity may change over time during imaging
– Direction & angle of insonation may alter echogenic
appearance
– In fatty livers, hemangiomas may appear hypoechoic
– Heterogeneous in large lesions
□ Hypoechoic areas within large lesions may
represent necrosis, hemorrhage, scar, or vessels
○ "Typical atypical" appearance
– Hypoechoic center with thick or thin hyperechoic rim
• Pulsed Doppler
○ In "high-flow hemangioma" may see feeding artery and
draining portal vein
• Color Doppler
○ May show vessels in periphery of tumor
– Blood supply is from hepatic artery
○ Typically undetectable color Doppler flow in lesion,
which is too slow to be sonographically detected
• Power Doppler
○ May detect slow flow within hemangiomas
• Contrast-enhanced US
○ Demonstrates same filling-in phenomenon as seen on
CECT
CT Findings
• NECT
○ Same attenuation as blood pool (aorta)
○ Giant hemangioma (> 10 cm)
– Heterogeneous hypodense mass
– Central low-attenuation scar
• CECT
○ Small hemangioma: < 2 cm
– Homogeneous "flash fill" enhancement in arterial and
venous phases
○ Typical hemangioma: 2-10 cm
– Arterial phase: Early peripheral, nodular,
discontinuous enhancement
– Venous: Progressive centripetal enhancement to
uniform filling, isodense to blood vessels
– Delayed: Persistent enhancement, similar to blood
pool
○ Giant hemangioma: > 10 cm
– Arterial: Peripheral nodular or globular discontiguous
enhancement
– Venous & delayed phases: Incomplete centripetal
filling (scar does not enhance)
○ Hyalinized (sclerosed) hemangioma
– Minimal enhancement
– Cannot be diagnosed with confidence by imaging
MR Findings
• T1WI
○ Small & typical hemangiomas
– Well marginated
– Isointense to blood; hypointense to liver
○ Giant hemangioma
– Hypointense to liver
– Central cleft-like area of marked decreased intensity
(scar or fibrous tissue)
• T2WI
○ Small & typical hemangiomas
– Hyperintense, "light-bulb bright" similar to spinal CSF
○ Giant hemangioma
– Hyperintense mass
– Marked hyperintense center (scar or fibrosis)
– Hypointense internal septa
• T1WI C+
○ Small hemangioma (< 2 cm)
– Homogeneous "flash fill" enhancement in arterial and
portal phases, similar to blood pool
○ Typical & giant hemangiomas
– Arterial phase: Peripheral, nodular discontinuous
enhancement
– Venous phase: Progressive centripetal filling
– Central scar: No enhancement & remains hypointense
Angiographic Findings
• Conventional
○ Dense opacification of lesion
○ "Cotton wool" appearance
– Pooling of contrast within hemangioma
○ Normal-sized feeders
○ Typically retain contrast beyond venous phase
Diagnoses: Liver
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