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Glowacki in 1982.
2
This classi
fi
cation system divides VAs
into two separate categories, vascular tumours (VTs) and
vascular malformations (VaMs).
3
Congenital soft-tissue VAs
can present anywhere in the body from head to toe, with
variable size and in
fi
ltration; thus, a multidisciplinary
approach is crucial in the management and treatment of
these patients. Consistent use of correct terminology will
improve communication between different specialists and
avoid misunderstandings.
Given the rarity of some of the VAs, and overlapping
clinical and imaging features, experience of the team taking
care of the patient is extremely important. The accurate
classi
fi
cation and treatment of VAs is best performed by
those groups who see a large volume of patients, and as a
consequence can see the patterns of VAs in the clinical
appearance coordinated with the imaging appearance. This
is why the development of multidisciplinary VAs centres is
essential for accurate diagnosis and management of these
patients. In the present authors
’
clinical practice, we often
see patients who say that their doctor had never seen
anything like that before and had no idea what it was,
let alone how to treat it.
VAs can be imaged using ultrasonography (US),
computed tomography (CT), CT angiography, digital
subtraction angiography, or magnetic resonance imaging
(MRI), and MR angiography/venography (MRA/MRV). US
is often used as the
fi
rst line of imaging, given the lack of
ionizing radiation, no need for sedation/general anaes-
thesia, and bed-side imaging capabilities. Structural im-
aging data can be combined with
fl
ow dynamics of the
VA, which is valuable in the classi
fi
cation of the lesion.
However, operator dependence and small
fi
eld of view are
limiting factors in diagnosis and follow-up. MRI is the
reference standard in most cases given the high soft-
tissue resolution, different sequences, and fat suppres-
sion capabilities enabling clear differentiation/demarca-
tion of the VA from surrounding soft tissues, along with
dynamic contrast-enhanced (DCE) imaging information.
DCE-MRA provides high temporal resolution and pro-
duces imaging of the lesion in the arterial, capillary,
venous, and delayed venous phases
4,5
in the order of
seconds.
6
Rapid DCE-MRA data acquisition is based on a
combination of parallel imaging and k-space under-
sampling.
7
View-sharing and keyhole techniques are used
by fully sampling the central k-space during each acqui-
sition, although only a small fraction of the k-space pe-
riphery is acquired at the same time. A full k-space
periphery is generated for each image by adding infor-
mation from previous and subsequent acquisitions to
obtain a sharp, high-resolution image with good image
contrast. The high-resolution components encoded in the
k-space periphery are relatively stable over time, whereas
the low-frequency k-space centre carries the signi
fi
cant
contrast changes during bolus passage.
The full anatomical extent of the anomaly can be evalu-
ated in relation to adjacent nerves, and MRA/MRV can
identify the feeding artery and draining vein (
Table 2
).
Response to treatment can be reliably evaluated over time
by changes in size and
fl
ow characteristics.
8,9
Vascular tumours
VTs include infantile haemangiomas (IHs), congenital
haemangiomas (CHs) including non-involuting congenital
haemangiomas (NICHs) and rapidly involuting congenital
haemangiomas (RICHs), as well as kaposiform hae-
mangioendotheliomas (KHEs), among others. Age of pre-
sentation (prenatal, neonatal, early childhood/adult),
presence or absence of overlying telangiectatic vessels,
lighter peripheral ring, presence of high
fl
ow, and tem-
poral evolution of the mass (involution, no involution) are
important clinical criteria to approach diagnosis in VTs.
Haemangiomas
Infantile haemangioma
IHs compromise approximately 90% of all VTs and are the
most common VTs of infancy with higher incidence in the
white Caucasian infants. The highest incidence is noted in
the preterm infants weighing less than 1000 g.
10
The head
and neck regions are involved most frequently (60% of
cases), followed by the trunk (25% of cases), and extremities
(15% of cases).
11
Table 1
Vascular anomalies (simpli
fi
ed and adapted from ISSVA 1996).
Vascular tumours
Infantile haemangiomas
Congenital haemangiomas
Rapidly involuting congenital haemangiomas
Non-involuting congenital haemangiomas
Kaposiform haemangioendothelioma
Others
Vascular malformations
Slow-
fl
ow vascular malformations
Venous malformations
Lymphatic malformations
Capillary malformations
Fast-
fl
ow vascular malformation
Arteriovenous malformations/
fi
stulas
Combined complex vascular malformations
Capillary
e
venous
Capillary
e
arteriovenous
Lymphaticovenous malformation
Table 2
Key magnetic resonance imaging features of vascular anomalies.
IH
VM LM
AVM
Solid mass
Yes
No
No
No
Phlebolith
No
Yes
No
No
Enhancement Avid
homogeneous
Variable None
(cysts
’
periphery)
Avid
serpiginous
DCE-MRA
Arterial
Venous None
Arterial
with early
venous
drainage
IH, infantile haemangioma; VM, venous malformation; LM, lymphatic mal-
formation; AVM, arteriovenous malformation; DCE-MRA, dynamic contrast-
enhanced magnetic resonance imaging.
A. Tekes et al. / Clinical Radiology 69 (2014) 443
e
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245