Diagnostic ultrasound ( PDFDrive )

CHAPTER 4 The Liver 109
A
B
C
D
FIG. 4.43 Sustained enhancement in the portal venous phase, on contrast-enhanced ultrasound (CEUS) and contrast-enhanced computed
tomography (CECT) scan, suggestive of a benign mass. (A) and (C) are arterial phase images on CT and CEUS, respectively, both showing arterial
phase hyperenhancement. (B) and (D) are portal venous phase images on CT and CEUS, respectively, both showing sustained enhancement and
a nonenhanced scar. This sustained enhancement is concordant on the two scans and suggests a benign tumor. This is a conirmed FNH. See
also Video 4.5. (With permission from Wilson S, Greenbaum L, Goldberg B. Contrast-enhanced ultrasound: what is the evidence and what are the
obstacles? AJR Am J Roentgenol. 2009;193[1]:55-60. 129 )
he sonographic appearance of cavernous hemangioma varies.
Typically the lesion is small (<3 cm in diameter), well deined,
homogeneous, and hyperechoic 139 (Fig. 4.46A). he increased
echogenicity has been related to the numerous interfaces between
the walls of the cavernous sinuses and the blood within. 140
Inconsistently seen and nonspeciic, posterior acoustic enhancement
has been correlated with hypervascularity on angiography 141
(Fig. 4.46H). Approximately 67% to 79% of hemangiomas are
hyperechoic, 142,143 of which 58% to 73% are homogeneous. 135,141
Other features include a nonhomogeneous central area containing
hypoechoic portions, which may appear uniformly granular (Fig.
4.46D-F) or lacelike in character (Fig. 4.46D); an echogenic
border, either a thin rim or a thick rind (Fig. 4.46E-G); and a
tendency toward scalloping of the margin (Fig. 4.46B). 144 Larger
lesions tend to be heterogeneous, with central hypoechoic foci
corresponding to ibrous collagen scars (Fig. 4.46C), large vascular
spaces, or both. A hemangioma may appear hypoechoic within
the background of a fatty iniltrated liver. 145 Calciication is rare
(Fig. 4.46I).
Hemangiomas are characterized by extremely slow blood low
that will not routinely be detected by either color or duplex
Doppler sonography. Occasional lesions may show a low to
midrange kilohertz (kHz) shit from both peripheral and central
blood vessels. he ability of power Doppler ultrasound, which