Classification and ultrasound findings of vascular anomalies in pediatric age: the essential

Fig. 12
Venous malformation. Compressible mass in the subcutane-
ous soft tissue (arrow). Note the dysplastic ectatic superficial veins 
(arrowheads) and the bluish discoloration of the overlying skin
Fig. 13
Venous malformation in 13-year-old girl. Sonogram shows 
well-margined masses with a “spongiform” echostructure, which is 
hypoechoic in comparison to the surrounding tissues. The presence of 
intralesional phlebolith (arrow)

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Journal of Ultrasound (2019) 22:13–25
1 3
the lesion has a direct involvement with the joint, since the 
possibility of hemarthrosis and subsequent damage of the 
articular cartilages are frequent [
48
]. Given the extreme 
variety of clinical and ultrasound presentations of vascular 
malformations, in case of doubt or, as mentioned, in doubt 
of joint involvement, it is always advisable to perform an 
MRI examination.
Lymphatic malformation
The lymphatic malformations are divided into macrocystic, 
microcystic, and mixed type.
The criterion of distinction between the macrocystic 
and microcystic form is not univocal. According to some, a 
1–2 cm cut-off must be identified to distinguish between the 
two forms, while according to others, macrocystic lesions 
should be considered as those that can be reduced by aspira-
tion and sclerotization [
8
].
The term “lymphatic malformation” has now replaced the 
old name of “lymphangioma” (whose suffix ‘oma’ should be 
applied to lesions with cell proliferation) [
1
, 
39
]. Clinically, 
like the previous ones, the lymphatic malformations are 
slow-growing lesions that can rapidly increase in size in case 
of intralesional bleeding. In the case of superficial micro-
cystic forms, it is possible to find the presence of micro-
vesicles present on the skin or on the mucous membranes.
Lymphatic malformations are more frequently superficial, 
although they can also arise in deeper regions [
49
]. The most 
frequent sites are the neck, the axillary region, and the medi-
astinum [
1
, 
7
, 
34
, 
39
].
With US the 
macrocystic lymphatic malformations
, which 
are the most frequent, appear as lesions containing numer-
ous cystic formations of variable dimensions with liquid 
content separated by thin hyperechogenic septa (Fig. 
15
). 
The lesion is deformable, and compression with the probe 
alters the shape of the cysts that never collapse completely, 
unlike the venous malformations [
50
–
52
]. At the B-mode, 
the cystic spaces can be anechoic or have a variable degree 
of echogenicity in relation to the presence of hemorrhages or 
infections. In some cases, the formation of fluid–fluid levels 
is possible (Fig. 
16
).
The 
microcystic lymphatic malformations
often appear 
as solid hyperechoic formations in which some scattered