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Table 2. International Society for the Study of Vascular Anomalies Classification of Vascular Anomalies (Simplified and Adapted from
)
VASCULAR ANOMALIES
Vascular tumors
Benign vascular tumors
Locally aggressive or borderline
vascular tumors Malignant vascular tumors
Infantile hemangiomas Congenital
hemangiomas
-Rapidly involuting
-Noninvoluting
-Partially involuting
Tufted angioma
Epithelioid hemangioma
Others
Kaposiform
hemangioendothelioma
Retiform hemangioendothelioma
Kaposi sarcoma
Others
Angiosarcoma
Epithelioid
hemangioendothelioma
Others
Vascular Malformations
Simple vascular malformations
Capillary
malformations
Lymphatic
malformations Venous malformations
Arteriovenous
malformations Arteriovenous fistula
-Cutaneous and/or
mucosal
-Telangiectasia
-Cutis marmorata
telangiectatica
congenital
-Nevus simplex
-Others
-Common
-Generalized lymphatic
anomaly
-Gorham-Stout disease
-Channel type
-Primary lymphedema
-Others
-Common
-Familial
cutaneo-mucosal
-Blue rubber bleb nevus
syndrome
-Glomuvenous
-Cerebral cavernous
malformation
-Others
-Sporadic
-In hereditary hemorrhagic
telangiectasia
-In capillary malformation
– arterio-venous
malformation syndrome
-Sporadic
-In hereditary hemorrhagic
telangiectasia
-In capillary malformation
– arterio-venous
malformation syndrome
Combined vascular malformations
Anomalies of major named vessels
Vascular malformations associated with other anomalies
macrocystic, microcystic, or mixed. The typical location is pos-
terior to the SCMmuscle. However, microcystic lesions tend to
occur above the mylohyoid level in the oral and perioral struc-
tures and submandibular spaces and may involve the parotid
gland. Lymphatic malformations have a tendency to infiltrate
across various cervical spaces or extend into the mediastinum
and adjacent anatomic structures are encircled/wrapped rather
than displaced. Typical imaging characteristics include the
trans-spatial extension including engulfment and encasement
of neurovascular structures as well as fluid-fluid levels in a
multilocular cystic structure with macrocystic and/or micro-
cystic elements. On US, echogenic appearance of parts of the
lesion is due to clusters of small abnormal lymphatic channels.
The content of the cystic elements varies from homogenous
to heterogeneous due to prior hemorrhage or infection.1,3,35
The hemorrhagic component or debris from previous infection
layering in the dependent portion of the cystic elements causes
the fluid-fluid levels. Postcontrast MR imaging sequences and
multiphasic time-resolved dynamic cMRA typically show no
contrast enhancement but may demonstrate enhancement
of the walls and septa of the cystic elements, particularly in
case of concomitant (prior) infection (Fig 12).7 The presence
of a lymphatic malformation in the posterior cervical triangle
may be associated with Turner syndrome and trisomy 21, 18,
and 13.3,12
Venous Malformation
Venous malformations are the most common low-flow vascular
malformations and the second most common vascular lesions of
the head and neck region (after hemangiomas). In the neck re-
gion, the lesions manifest at birth or in early infancy (although
they may stay dormant till adulthood) as a painless soft blue
or purplish mass or may be symptomatic depending on po-
tential accompanying local inflammatory changes. Local pain,
bleeding, and cosmetic concerns are the leading symptoms at
the time of presentation. Venous malformations are develop-
mental anomalies composed of dysmorphic venous channels
lined by flattened endothelium. They are characteristically lo-
cated in the skeletal muscles of the neck, including the mas-
seter, pterygoid, trapezius, and SCM muscles, or may involve
the mandibular region. The presence of phleboliths is a key
imaging feature of venous malformations. US demonstrates a
compressible, hypoechoic heterogeneous lesion with detectible
flow on Doppler in about 40% of the cases. 35 The phleboliths
appear as hyperechoic foci and show posterior acoustic shad-
owing. On MR imaging studies, trans-spatial extension of the
venous malformation may be identified. The lesion is typically
T1- isointense and T2-hyperintense to normal muscle, with het-
erogeneous contrast enhancement. Distinct areas of T2 hyper-
intense signal may represent venous lakes. Fluid-fluid levels
Dremmen et al: Imaging Lumps and Bumps of the Neck in Children
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