Fortuitously discovered liver lesions

Table 1 Typical criteria of hemangioma

B-mode criteria
Less than 3 cm in diameter
Echo-rich structure
Homogeneous interior
Round or slightly oval shape
Smooth outline
Absence of any halo sign
Possible detection of feeding and draining vessel
Absence of any signs of invasive growth
Dorsal through-enhancement

Reproduced with permission from Dietrich et al[65].

Table 2 Ultrasound findings in 400 patients with hemangioma n (%)

Characteristics	n = 400
Size, cm (mean ± SD)	2.6 ± 3.1
B-mode, echogenicity
Echo-rich	363 (91)
Isoechoic or echopoor	37 (9)
Vascularity assessed by colour Doppler imaging
No intra-lesional vessels	379 (95)
Intra-lesional vessels (hypervascular)	21 (5 )
Peripheral nodular enhancement	328 (82)
Strong homogenous arterial enhancement	31 (8)
No specific enhancement pattern or not determinable (e.g., due to size of the lesion, solitary fibrotic nodule)	41 (10)
Complete iris diaphragm phenomenon	320 (80)
Incomplete iris diaphragm phenomenon	80 (20)

Reproduced with permission from Dietrich et al[65].

Table 3 Ultrasound findings in 424 patients with focal nodular hyperplasia and 36 patients with hepatocellular adenoma

	Focal nodular hyperplasia	Hepatocellular adenoma
	(n = 424)	(n = 36)
Size of lesion, mm (range)	49 ± 24 (12-110)	34 ± 22 (20-120)
Conventional B-mode ultrasound
Echo texture
Hypoechoic	361	81
Isoechoic	382	20
Hyperechoic	6	8
Central scar	241	0
Colour/power Doppler imaging
Hypervasular	369	33
Radial vascular architecture	234	3
Contrast-enhanced ultrasound
Arterial phase enhancement	424	36
(Early) Portal venous phase enhancement	406	6

¹Depending on the technique and ultrasound machine used; all in a sonographically bright liver. Reproduced with permission from Dietrich et al[66].

Table 4 Typical enhancement pattern for the characterization of focal liver lesions

Lesion	Arterial phase	Portal venous and late phase
Hemangioma (Figures 1 and 2)	Circular vascular enhancement without central intratumoral vessels	Nodular enhancement and "fill-in" pattern
Focal nodular hyperplasia (Figures 3 and 4)	Radial centrifugal or "spoke wheel" pattern, then rapid, complete hyperhancement	Iso- or hyperenhancement
Focal fatty sparing (Figure 5)	Central arterial blood supply	Isoenhancement
Metastasis (Figure 6)	Asymmetrical, chaotic enhancement configuration	Hypoenhancement
Hepatocellular carcinoma (Figure 7)	Hyperenhancement and disorganized vascularity	Iso- or hyperenhancement, depending upon tumor differention

Reproduced with permission from reference Dietrich et al[81].