AJR 2000; 174:597-608
© American Roentgen Ray Society
Vascular Malformations and Hemangiomas
A Practical Approach in a Multidisciplinary Clinic
Lane F. Donnelly1,2,3,
Denise M. Adams1,4 and
George S. Bisset, III1,2
1
Clinic for the Treatment of Vascular Malformations, Duke University Medical
Center, Durham, NC 27710.
2
Department of Radiology, Division of Pediatric Radiology, Duke University
Medical Center, Durham, NC 27710.
3
Present address: Department of Radiology, Children's Hospital Medical Center
and the University of Cincinnati, 3333 Burnet Ave., Cincinnati, OH
45229-3039
4
Department of Pediatrics, Division of Hematology-Oncology, Duke University
Medical Center, Durham, NC 27710.
Received June 24, 1999;
accepted after revision September 13, 1999.
This is the third in a series of Centennial Dissertations that the
AJR is publishing this year in honor of the former presidents of the
American Roentgen Ray Society, two of whom are pictured above.
Address correspondence to L. F. Donnelly.
Introduction
Vascular malformatiyons and hemangiomas can cause significant morbidity and
even mortality in both children and adults. For a number of reasons,
physicians often confuse these lesions. The nomenclature for classifying these
lesions is often used interchangeably and inappropriately. Clinically
significant malformations are uncommon, and patients with these malformations
are rarely encountered in primary medical facilities, rendering most
physicians inexperienced in providing optimal care. Radiologists may become
involved in the care of these patients when imaging or imaging-guided therapy
is requested; therefore, knowledge of the imaging and treatment of these
patients is essential. This article reviews the clinical and imaging
approaches to vascular malformations and hemangiomas used in the
multidisciplinary clinic at our institution, stressing a multidisciplinary
approach, a practical categorization scheme, characteristic imaging findings,
and commonly encountered clinical scenarios.
A Team Approach
The care of children and adults with hemangiomas and vascular malformations
requires the expertise of multiple subspecialties. The clinic for the
treatment of vascular malformations at our institution has representatives
from pediatric hematology-oncology, pediatric radiology, pediatric surgery,
pediatric dermatology, pediatric otolaryngology, and orthopedic surgery. The
combined skills and knowledge of these subspecialists helps to provide the
wide range of services that these children may require. These services include
medical therapy, tailored imaging studies, imaging-guided interventional
procedures, surgical resection, laser therapy, and monitoring for shortand
long-term complications.
Because expertise in multiple fields is needed to effectively treat these
patients, patients with hemangiomas and vascular malformations are often best
served in a tertiary center with a multidisciplinary clinic. Treatment is
complicated by the relative rarity of these lesions
[1], resulting in inexperience
with diagnosis and treatment. Many of the patients that we see in our clinic
have previously seen several physicians and are frustrated with the
inexperience and lack of answers they have encountered
[1]. Often the patients'
families have obtained information from dedicated Web sites and have become
more educated than the physicians from whom they seek medical care. The
patients at our clinic often have undergone multiple surgical procedures,
usually resulting in little improvement or even a worsening of symptoms.
Physicians have recommended radical surgery to many patients. Conversely, many
children who might benefit from other therapeutic approaches have been treated
with watchful waiting. Many patients with vascular malformations have been
misinformed that their lesions are hemangiomas and will eventually resolve. In
addition, malformations that involve areas such as the face can create
difficult social or emotional problems for the patients and their families.
Because of these adversities, one of the most important team members in our
clinic is our patient advocate. The advocate assists families by providing
educational materials (such as a hemangioma-vascular malformation newsletter),
addressing psychosocial concerns, and putting families in contact with others
who have been through similar experiences.
Categorization
Both hemangiomas and vascular malformations are endothelial malformations.
The classification of and nomenclature used to describe endothelial
malformations has been a source of confusion. Historically, lesions were named
according to the size of the channels in the lesions and the type of fluid the
lesions contained. Blood-containing lesions were called hemangiomas and were
separated into capillary hemangiomas, strawberry hemangiomas, and cavernous
hemangiomas on the basis of channel size. Lymph-containing lesions were
referred to as lymphangiomas or cystic hygromas. This classification system
has been replaced by one described in 1982 by Mulliken and Glowacki
[2]. This newer classification
system is an important tool in establishing and separating the diagnoses of
these two lesions. This system separates endothelial malformations into two
large groups, hemangiomas and vascular malformations, on the basis of their
natural history, cellular turnover, and histology
[2]
(Table 1). Infantile
hemangiomas indicate endothelial proliferation and proceed through a two-stage
process of growth and regression. Hemangiomas tend to be small or absent at
birth and often are not initially noticed by parents and caregivers. Shortly
after birth they undergo a proliferative phase, with rapid growth that may
last several months. They then undergo a stationary period, followed by a
period of involution.
Conversely, vascular malformations are always present at birth and enlarge
in proportion to the growth of the child. They do not involute and remain
present throughout the patient's life
[2]. Vascular malformations are
subcategorized as lymphatic, capillary, venous, arteriovenous, and mixed
malformations on the basis of their histologic makeup
[2,3,4,5].
Although MR imaging has been used to classify vascular malformations into one
of these categories [4,
6,7,8,9,10],
a more pertinent issue is classifying vascular malformations as either
low-flow or high-flow lesions
[3,
5]. Malformations with arterial
components are considered high-flow lesions and those without arterial
components are considered low-flow lesions.
Imaging
The two noninvasive imaging techniques that are most useful in the
examination of vascular malformations are MR imaging and sonography. In our
clinic, MR imaging is the primary imaging technique in the evaluation of
suspected vascular malformations.
The primary goals of imaging vascular malformations or hemangiomas include
characterizing the lesion and discovering the anatomic extent of disease
[3]. Knowing which tissues the
vascular malformation involves and whether adjacent vital structures, such as
neurovascular bundles, are involved by the lesion is important (Fig.
1A,1B,1C).
Such information is vital to planning surgery or imaging-guided procedures. On
physical examination, determining whether the subcutaneous tissue, the
underlying deep muscular tissues, or both are involved is difficult (Fig.
2A,2B).

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Fig. 1A. 4-month-old female infant with extensive distribution of infantile
hemangioma revealed on MR imaging. Photograph shows hemangioma of right
perirectal region, which was extent of disease suggested on physical
inspection. Because of foot drop on physical examination, MR imaging of lumbar
spine was performed.
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Fig. 1B. 4-month-old female infant with extensive distribution of infantile
hemangioma revealed on MR imaging. Coronal (B) and axial (C)
T2-weighted fat-saturated fast spin-echo MR images (3000/98 [TR/TE]) show
abnormally increased signal intensity (long arrow, B) in
subcutaneous region of right buttock. Extensive hemangioma throughout
retroperitoneum of pelvis and abdomen is seen as abnormally high signal
intensity (short arrows, B and C). Mass was found to
engulf sacrum, rectum, uterus, and vagina. Note prominent veins that appear as
signal voids.
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Fig. 1C. 4-month-old female infant with extensive distribution of infantile
hemangioma revealed on MR imaging. Coronal (B) and axial (C)
T2-weighted fat-saturated fast spin-echo MR images (3000/98 [TR/TE]) show
abnormally increased signal intensity (long arrow, B) in
subcutaneous region of right buttock. Extensive hemangioma throughout
retroperitoneum of pelvis and abdomen is seen as abnormally high signal
intensity (short arrows, B and C). Mass was found to
engulf sacrum, rectum, uterus, and vagina. Note prominent veins that appear as
signal voids.
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Fig. 2A. Venous malformation involving posterior abdominal wall in 3-year-old
boy with pain and progressively enlarging lesion. Photograph shows skin
involvement with red discoloration and enlargement of underlying soft
tissues.
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Fig. 2B. Venous malformation involving posterior abdominal wall in 3-year-old
boy with pain and progressively enlarging lesion. Axial T2-weighted
fat-saturated fast spin-echo MR image (3500/72 [TR/TE]) shows
high-signal-intensity mass predominantly involving skin and subcutaneous
tissue. Note involvement of underlying abdominal wall musculature (large
arrow) and prominent draining veins (small arrows).
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When characterizing suspected vascular malformations, important
differentiating features include the presence or absence of a discrete mass,
overlying skin thickening, and the presence of prominent vessels
[3] (Fig.
2A,2B).
When the physical examination and clinical history are diagnostic or highly
suggestive of a vascular malformation, the most important characterizing
feature is whether the lesion is a high- or low-flow vascular
malformation.
Most information needed to examine the lesion is available from a
combination of T1-weighted, fat-saturated T2-weighted, and gradient-echo
(flow-weighted) MR images. Our protocols include each of these sequences
obtained in the axial plane, with the addition of coronal and sagittal fast
spin-echo T2-weighted images as needed. We find the axial plane to be the most
helpful in depicting the relationship between the lesion, neurovascular
structures, and tissue planes. Gadolinium-enhanced images have been advocated
as helpful in differentiating between low-flow vascular malformations such as
lymphangiomas and venous malformations
[6,
11]. We have not found this
distinction to be helpful in our decision making and do not use gadolinium in
the evaluation of vascular malformations. Other potential imaging sequences
that have been advocated as useful in the evaluation of vascular malformations
include MR angiography, venography, and lymphangiography
[3,4,5,6,7,8,9,10].
Sonography has been advocated as useful in examining soft-tissue masses
that are suggestive of hemangiomas or vascular malformations
[4,
12,
13]. Vessel density as
depicted on Doppler sonography has been used in differentiating other types of
masses from vascular malformations
[14]. Certainly, the Doppler
characteristics of vascular malformations are helpful in differentiating low-
from high-flow vascular malformations. We have also found the sonographic
depiction of abundant low-flow vascular channels to be a predictor for the
potential success of percutaneous sclerosis
[15], and we use sonography to
guide needle placement during percutaneous sclerosis.
Infantile Hemangiomas
Hemangiomas are benign neoplasms of endothelial cells. As discussed
previously, they undergo a characteristic two-stage process of growth and
regression [2]. At birth, the
lesions are often small and inconspicuous, with 60% absent at birth
[5,
16]. The lesions can appear as
an erythematous macule, a blanching macule, or an area of localized
telangiectasia [5,
16]. Shortly after birth, the
phase of rapid proliferation occurs, which can last for several months. This
proliferation phase corresponds to a rapid period of growth of endothelial
cells that form syncytial masses with and without vascular lumens. This phase
has also been defined by high expression of angiogenic factors such as
vascular endothelial growth factor and basic fibroblast growth factor. The
typical hemangioma will begin to involute approximately 10 months after birth
and 50% of lesions are completely resolved in 5 years
[5].
Hemangiomas are the most common childhood tumor, occurring in 12% of
infants [4,
5,
17,
18]. Hemangiomas are found
with greater frequency in girls, whites, premature infants, and twins
[4,
5,
19,20,21].
During the proliferative phase, hemangiomas are high-flow lesions
[4] that are often revealed by
bruit, pulsatility, and increased warmth. Hemangiomas can have deep,
superficial, or mixed components. The clinical appearance of hemangiomas
varies with the degree of dermal involvement and the depth of the lesions
[5,
18]. A characteristic
strawberry appearance is present when the lesions involve the skin
(Fig. 3). Deep hemangiomas,
which do not involve the subcutaneous tissues, may have a blue appearance
[3] (Fig.
4A,4B,4C).

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Fig. 3. Kaposiform hemangioendothelioma involving lip and left face in
8-month-old female infant who had been treated with steroids for
Kasabach-Merritt syndrome. Photograph shows superficial involvement causing
skin to appear red. Note deep component distorting region inferiro to left
ear. Region inferior to left lip developed fissures.
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Fig. 4A. Infantile hemangioma in 21-day-old male neonate. Photograph shows
lobulated mass extending from region of knee. Lack of superficial involvement
renders lesion bluish rather than strawberry red.
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Fig. 4B. Infantile hemangioma in 21-day-old male neonate. Axial T1-weighted
MR image (500/14 [TR/TE]) shows mass (arrows) with signal intensity
similar to that of skeletal muscle. Note low signal intensity and prominent
veins.
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Fig. 4C. Infantile hemangioma in 21-day-old male neonate. Axial T2-weighted
fat-saturated fast spin-echo MR image (4000/98) shows heterogeneous
high-signal-intensity mass (arrows) confined to subcutaneous tissue.
Because lesion did not have classic temporal pattern of growth on physical
examination, biopsy was performed to confirm diagnosis of hemangioma.
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Most hemangiomas require no therapy. Even many large lesions are treated
conservatively because of the characteristic pattern of involution. Although
hemangiomas are typically benign, a percentage of them develop
life-threatening complications. Potential complications include
Kasabach-Merritt syndrome (consumptive coagulopathy), compression of vital
structures (e.g., airway, orbital structures), fissure formation, ulceration,
and bleeding [3]. These
complications usually occur in the rapid proliferate phase and can be
associated with a mortality rate as high as 20-30%
[5].
Kasabach-Merritt syndrome consists of thrombocytopenia, anemia, and
consumptive coagulopathy associated with a proliferative hemangioma. The
syndrome has recently been shown to be associated with two specific subtypes
of lesions, kaposiform hemangioendotheliomas and tuft angiomas
[22,
23]
(Fig. 3). These lesions are not
typical infantile hemangiomas and respond poorly to standard therapy
[22,
23]. Their time to resolution
is also much longer than that of typical infantile hemangiomas.
Numerous therapies have been used in an attempt to treat hemangiomas when
complications develop during the proliferative phase. These regimes include
high-dose steroids,
-interferon, and chemotherapeutic agents. The
prolonged use of systemic agents during the period of endothelial
proliferation is often associated with increased side effects. The current
first line of treatment is systemic administration of corticosteroids
[20,
24]. Approximately 30% of
hemangiomas will respond dramatically to corticosteroids and another 40% will
have some response [20,
24]. Unfortunately, the doses
of corticosteroids required to treat hemangiomas are often associated with
multiple side effects. These include severe irritability, weight gain,
cushingoid appearance, growth delay, hypertension, diabetes, gastroesophageal
reflux, and susceptibility to infections. Patients must be closely monitored
for these complications. When corticosteroid therapy fails to improve
symptoms, other antiangiogenesis drugs, such as
-interferon, can be
used [24,
25]; however,
-interferon therapy has been associated with irreversible neurologic
spastic diplegia [26] and is
now used much less commonly to treat hemangiomas. Chemotherapy with
vincristine sulfate, surgical excision, and embolization may be used in
refractory cases [4,
24,
27]. Laser therapy can be used
to treat complications related to the superficial portions of the lesions such
as ulceration, bleeding, and marked skin discoloration
[18,
28,
29].
In most cases, the diagnosis of hemangioma can be made on the basis of the
temporal growth history and appearance on physical inspection; therefore,
imaging is usually not required. In atypical cases, imaging may be performed
to characterize the lesion and examine the anatomic extent of disease. MR
imaging of proliferating hemangiomas often shows a discrete lobulated mass
that is hyperintense to muscle on T2-weighted images and isointense to muscle
on T1-weighted images [6].
Typically, prominent draining veins will be identified as both central and
peripheral high-flow vessels
[6] (Fig.
4A,4B,4C).
Hemangiomas usually enhance diffusely with gadolinium
[6]. Involuting hemangiomas can
indicate areas of fibrofatty tissue with associated high signal intensity on
T1-weighted images and less contrast enhancement than that of proliferating
hemangiomas [6]. The density of
blood vessels as seen on Doppler sonography has also been advocated as helpful
in making the diagnosis of hemangioma during the proliferative stage
[14].
Unfortunately, many of the soft-tissue malignancies of infancy, such as
fibrosarcoma or rhabdomyosarcoma, can have an imaging appearance similar to
that of proliferate hemangiomas
[30,
31]. Therefore, cases that do
not exhibit the typical appearance and growth patterns for hemangioma are
often biopsied to exclude malignancy.
Low-Flow Vascular Malformations
Low-flow vascular malformations include primarily venous, lymphatic, and
mixed malformations. Venous malformations are dysplasias of small and large
venous channels associated with a variable amount of hamartomatous stroma
[3]. The venous channels
connect with adjacent veins. Many venous malformations cause pain. Often
patients will suffer from increasing symptoms in late childhood or early
adulthood. Other clinical problems related to venous malformations include
decreased range of motion and deformity. Venous malformations rarely regress
[32,
33]. Treatment for venous
malformations includes elastic compression garments, percutaneous sclerosis,
and surgical excision [32,
33].
Lymphatic malformations consist of chylefilled cysts lined with endothelium
[34]. The most common
locations for lymphatic malformations include the neck (approximately 75%) and
axilla (approximately 25%), with less common locations including the
mediastinum, retroperitoneum, pelvis, and groin
[3,
35,
36]. When lymphatic
malformations occur in the neck and axilla, they are often called cystic
hygromas. Most lymphatic malformations present early in childhood, with 65%
present at birth and 90% seen by the age of 2 years
[3,
34,35,36,37].
The primary therapy for lymphatic malformations that occur in infancy is
surgical excision [35,
38,39,40,41,42].
Another therapeutic option is percutaneous sclerotherapy using agents that
include absolute ethanol, bleomycin, cyclophosphamide, doxycycline, alcohol
solution of zein, and OK-432
[37,
43,44,45,46,47,48,49].
Chemotherapy, such as cyclophosphamide, has also been used for
life-threatening lesions.
A high percentage of vascular malformations, referred to as mixed vascular
malformations, have different tissue characteristics in different portions of
the lesion. Recognizing that the lesion is a low-flow vascular malformation is
more important than determining whether the lesion is predominantly venous or
lymphatic when making treatment decisions.
The appearance of a low-flow vascular malformation on MR imaging depends on
the composition of lymphatic and venous components. The venous portions of a
malformation will appear as a collection of serpentine structures separated by
septations. These serpentine structures represent slow-flowing blood in the
venous channels and appear as high signal intensity on T2-weighted images and
intermediate signal intensity on T1-weighted images
[9] (Fig.
5A,5B).
Phleboliths may be present and appear as round, low-signal-intensity lesions
on MR imaging [4,
6,
9,
50]. Gadolinium-enhanced
T1-weighted images may show enhancement of the slow-flowing venous channels
[6]. Lymphatic components of
the malformation may contain cystic structures of various sizes ranging from
macrocystic to microcystic [5]
(Fig.
6A,6B).
These cystic structures typically appear as high signal intensity on
T2-weighted MR images and do not exhibit central enhancement with gadolinium
[5]. Fluid-fluid levels are
often present [51].
Characteristic imaging findings of vascular malformations include a tendency
to be infiltrative, lack of respect for facial planes, and involvement of
multiple tissue types such as muscle and subcutaneous fat
[3] (Fig.
1A,1B,1C).

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Fig. 5A. Venous malformation of left anterior pelvis in 10-year-old girl.
Axial T1-weighted MR image (500/8 [TR/TE]) shows mass (arrows)
confined to subcutaneous tissues. Mass is isointense in signal intensity to
adjacent muscle. Note prominent draining veins.
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Fig. 5B. Venous malformation of left anterior pelvis in 10-year-old girl.
Axial T2-weighted fat-saturated fast spin-echo MR image (4000/98) shows mass
(arrows) consisting of multiple high-signal-intensity serpentine
structures. Mass is confined to subcutaneous tissue. Note prominent draining
veins.
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Fig. 6B. Lymphatic malformation involving arm and chest wall of 4-month-old
female infant. Coronal T2-weighted fat-saturated fast spin-echo MR image
(4316/98 [TR/TE]) shows multilocular cystic-appearing mass (m) involving
subcutaneous tissues of left upper extremity. Note chest wall involvement
(arrow).
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Low-flow vascular malformations can be difficult to treat. Surgical
resection, medical therapy, and transarterial embolization have all had
limited success [1,
15,
27,
32,
52,
53]. Multiple studies have
advocated the use of percutaneous sclerosis of low-flow vascular malformations
and it is currently the treatment of choice
[1,
15,
27,
32,
52,
53]. Ethanol is the most
commonly used sclerosing agent. Other agents include sodium tetradecyl
sulfate, ethibloc, bleomycin, cyclophosphamide, doxycycline, alcohol solution
of zein, and OK-432 [37,
43,44,45,46,47,48,49].
Percutaneous sclerotherapy is usually performed under general anesthesia.
Direct puncture of the vascular channels is performed using a combination of
sonographic and fluoroscopic guidance
[15].
Soft-tissue swelling generally increases in the region of the malformation
immediately after the procedure (Fig.
7A,7B).
As the necrosis and inflammation induced by the sclerosis begin to retract
with fibrous scar formation, the lesion will decrease in size. The complete
clinical effect of the sclerosis may not be evident for several months (Fig.
8A,8B,8C).
Patients and their families must be informed of this expected course so that
they do not have faulty expectations. In our experience with percutaneous
sclerosis for low-flow vascular malformations, approximately 20% of patients
will have complete relief of symptoms after one sclerotherapy procedure. An
equal amount will have no therapeutic benefit. Approximately 60% of patients
will have a decrease in their clinical symptoms significant enough to improve
their quality of life; therefore, approximately 80% of patients will benefit
from percutaneous sclerosis.

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Fig. 7A. Change in appearance after percutaneous ethanol sclerosis of venous
malformation in 7-year-old girl with pain. Photograph before procedure shows
bluish discoloration of skin with underlying fullness.
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Fig. 7B. Change in appearance after percutaneous ethanol sclerosis of venous
malformation in 7-year-old girl with pain. Photograph 4 days after sclerosis
with only 7 ml of ethanol shows marked increase in swelling, hematoma, and
area of skin ulceration. Findings all resolved over next several weeks;
patient's pain resolved and fullness decreased.
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Fig. 8A. Percutaneous sclerosis of venous malformation of foot of an
18-year-old female dancer with pain. Sagittal T2-weighted fat-saturated fast
spin-echo MR image (4000/98 [TR/TE]) obtained before procedure shows
serpentine areas of high signal intensity (arrows).
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Fig. 8B. Percutaneous sclerosis of venous malformation of foot of an
18-year-old female dancer with pain. Image from percutaneous venogram obtained
during sclerosis shows tangle of venous structures and draining veins. Note
angiocatheter (arrow).
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Fig. 8C. Percutaneous sclerosis of venous malformation of foot of an
18-year-old female dancer with pain. Sagittal T2-weighted fat-saturated fast
spin-echo MR image (4000/98) obtained 7 months later than A and
B shows resolution of serpentine high-signal-intensity structures and
replacement with low-signal-intensity structures (arrows), most
likely fibrotic scars.
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The procedure is not without potential risks. Complications have been
reported in as many as 10-15% of cases and include skin necrosis, nerve damage
(sensory or motor), pain and swelling, muscle atrophy or contracture, deep
vein thrombosis, pulmonary embolism, disseminated intravascular coagulation,
and cardiopulmonary collapse
[1,
15]. In our experience, 31% of
patients will develop temporary adverse effects that will prolong recovery. It
is important that the patient understand this before the procedure. Because of
these potential risks, we monitor the patients in the hospital for 24 hr after
the procedure.
High-Flow Vascular Malformations
Any lesion that has arterial components is considered a high-flow
malformation. These include arteriovenous malformations (AVM) and
arteriovenous fistulas. During the proliferating stage, infantile hemangiomas
may also be considered high-flow lesions. AVMs represent a direct connection
between the arterial and the venous systems
[1,
3,
4]. The lesions may present in
childhood or adulthood and are often exacerbated during puberty or pregnancy
[4,
54]. Presenting symptoms
include congestive heart failure, embolism, pain, bleeding, and ulceration
[1]. On physical examination,
the lesions may appear blue and may feel warm with pulsating and thrill
because of the increased blood flow. Lesions tend to grow with the child but
can enlarge rapidly as a result of thrombosis, infection, or hormonal
stimulation [4,
54]. High-flow vascular
malformations are rare.
MR imaging and Doppler sonography can be used for both diagnosis and
follow-up of AVMs after therapy
[1]. On MR imaging, the lesions
appear as a tangle of multiple flow voids
[1] that indicate high flow on
gradient-echo images [1].
Although the lesions can be associated with surrounding edema or fibrofatty
stroma, usually no focal discrete soft-tissue mass is found (Fig.
9A,9B,9C)
[3]. Color Doppler sonography
indicates a direct connection between the arterial and the venous systems and
resistive indexes indicate low-resistance flow
[1] (Fig.
10A,10B,10C,10D).
The most effective treatment for AVMs is transarterial embolization
[1] (Fig.
10A,10B,10C,10D).

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Fig. 9B. High-flow vascular malformation of foot in 12-year-old boy.
Short-axis T2-weighted fat-saturated fast spin-echo MR image (3200/76) shows
multiple tubular flow voids (arrow) with surrounding edema.
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Fig. 10A. Embolization of arteriovenous malformation of liver in female
neonate who presented with severe congestive heart failure requiring tracheal
intubation and arterial pressers. Color Doppler sonogram of liver before
embolization shows large feeding artery (long arrow) communicating
with large draining vein (short arrow).
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Fig. 10B. Embolization of arteriovenous malformation of liver in female
neonate who presented with severe congestive heart failure requiring tracheal
intubation and arterial pressers. Arteriogram before embolization performed
with catheter in hepatic artery shows tangle of arterial structures in liver
and large draining vein (arrows).
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Fig. 10C. Embolization of arteriovenous malformation of liver in female
neonate who presented with severe congestive heart failure requiring tracheal
intubation and arterial pressers. Arteriogram after embolization shows
elimination of flow through arteriovenous malformation. Patient's congestive
heart failure resolved immediately and she is currently doing well 1 year
later.
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Fig. 10D. Embolization of arteriovenous malformation of liver in female
neonate who presented with severe congestive heart failure requiring tracheal
intubation and arterial pressers. Color Doppler sonogram after procedure shows
thrombosis of large draining vein (arrow).
|
|
Transarterial embolization is performed under general anesthesia in
children. Coaxial systems are used to achieve cannulation of subselective
arteries. It is important to embolize subselectively because when embolization
is performed in proximal feeding arteries, recruitment of other feeding
vessels to the AVM can occur and access to these vessels may have been
eliminated [4]. Materials used
for embolization include absolute ethanol, coils, and particles
[1]. After embolization of each
feeding vessel, a second arteriogram is obtained to examine for parasitization
by other feeding vessels. If subselective arterial access to the AVM is not
possible because of previous surgery, previous embolization, or difficult
anatomy, direct puncture of the feeding vessels of the AVM can be achieved
with sonographic guidance
[1].
Syndromes Associated with Vascular Lesions
Both hemangiomas and vascular malformations can be seen in association with
certain syndromes. Knowledge of these associations aids in obtaining
appropriate imaging studies to examine for additional vascular malformations
or other lesions. Lymphatic malformations can be associated with Turner's
syndrome, Down's syndrome, trisomies 13 and 18, and Noonan's syndrome
[55]. In blue rubber bleb
nevus syndrome, venous malformations can be seen involving the skin,
musculoskeletal system, and gastrointestinal system
[4,
5] (Fig.
11A,11B,11C).
The skin lesions are often dome-shaped and painful
[5]. Maffucci's syndrome refers
to venous malformations and multiple enchondromatosis
[4]. Hemangiomas can be
associated with a number of abnormalities. One cluster of abnormalities has
been referred to as the PHACE syndrome: posterior fossa abnormalities, facial
hemangiomas, arterial abnormalities, cardiovascular defects, and eye
abnormalities [56,
57] (Fig.
12A,12B,12C).
The syndrome is also associated with a supraumbilical midline raphe
[56,
57] (Fig.
12A,12B,12C).
Klippel-Trénaunay syndrome is a combined
capillarylymphaticvenous malformation of the trunk or
extremities in association with limb overgrowth
[5]. Sturge-Weber syndrome is a
trigeminal nerve distribution capillary malformation with intracranial
abnormalities [5]. Proteus
syndrome includes cutaneous and visceral vascular malformations with pigmented
nevi, hemihypertrophy, hand or foot overgrowth, exostoses, and lipomatosis
[5].

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Fig. 11B. Blue rubber bleb nevus syndrome in 11-year-old boy. Axial
T2-weighted fat-saturated fast spin-echo MR image (4550/84 [TR/TE]) shows
venous malformation as lobulated, high-signal-intensity mass
(arrows). Patient also suffered bleeding from multiple
gastrointestinal sources because of other venous malformations of
gastrointestinal tract.
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Fig. 12A. PHACE (posterior fossa abnormalities, facial hemangiomas, arterial
abnormalities, cardiovascular defects, and eye abnormalities) syndrome in
1-month-old female infant. Photograph of face shows hemangioma of right orbit
and ear. Eye is closed because of mass effect from hemangioma.
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Fig. 12B. PHACE (posterior fossa abnormalities, facial hemangiomas, arterial
abnormalities, cardiovascular defects, and eye abnormalities) syndrome in
1-month-old female infant. Axial T2-weighted fast spin-echo MR image (2800/100
[TR/TE]) with fat saturation through orbits shows lobulated
high-signal-intensity hemangioma (large arrow) surrounding right
globe. Note abnormal high signal intensity in subcutaneous region surrounding
right ear (small arrows).
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Fig. 12C. PHACE (posterior fossa abnormalities, facial hemangiomas, arterial
abnormalities, cardiovascular defects, and eye abnormalities) syndrome in
1-month-old female infant. Photograph shows supraumbilical midline raphe.
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Conclusion
Hemangiomas and vascular malformations are endothelial lesions that can
present with a number of serious medical problems. Knowledge of the
differentiating clinical features and characteristic imaging findings of these
lesions is essential for providing appropriate monitoring and therapy. We have
presented the approach used to examine these patients when seen in a
multidisciplinary clinic.
References
-
Yakes WF, Rossi P, Odink H. Arteriovenous malformation management.
Cardiovasc Intervent Radiol
1996;19:65-71[Medline]
-
Mulliken JB, Glowacki J. Hemangiomas and vascular malformations in
infants and children: a classification based on endothelial characteristics.
Plast Reconstr Surg
1982;69:412-422[Medline]
-
Fordham LA, Chung CJ, Donnelly LF. Congenital vascular and
lymphatic malformations of the head and neck. Radiol Clin North
Am 1999 [in press]
-
Burrows PE, Laor T, Paltiel H, Robertson RL. Diagnostic imaging in
the evaluation of vascular birthmarks. Dermatol Clin
1998;16:455-488[Medline]
-
Fishman SJ, Mulliken JB. Hemangiomas and vascular malformations of
infancy and childhood. Pediatr Clin North Am
1993;40:1177-1200[Medline]
-
Meyer JS, Hoffer FA, Barnes PD, Mulliken JB. Biological
classification of soft-tissue vascular anomalies: MR correlation.
AJR
1991;157:559-564[Free Full Text]
-
Laor T, Hoffer FA, Burrows PE, Kozakewich HP. MR lymphangiography
in infants, children, and young adults. AJR
1998;171:1111-1117[Abstract/Free Full Text]
-
Laor T, Jaramillo D, Hoffer FA, Kasser JR. MR imaging in congenital
lower limb deformities. Pediatr Radiol
1996;26:381-387[Medline]
-
Rak KM, Yakes WF, Ray RL, et al. MR imaging of symptomatic
peripheral vascular malformations. AJR
1992;159:107-112[Abstract/Free Full Text]
-
Laor T, Burrows PE, Hoffer FA. Magnetic resonance venography of
congenital vascular malformations of the extremities. Pediatr
Radiol
1996;26:371-380[Medline]
-
Barnes PD, Burrows PE, Hoffer FA, Mulliken JB. Hemangiomas and
vascular malformations of the head and neck: MR characterization.
AJNR
1994;15:193-195[Medline]
-
Paltiel HL, Burrows PE, Mulliken JB. Color Doppler ultrasound of
soft tissue vascular anomalies. Radiology
1994;193:292-295
-
Dubois J, Garel L, Gignon A, Laberge L, Filiatrault D, Powell J.
Imaging of hemangiomas and vascular malformations in children. Acad
Radiol
1998;5:390-400[Medline]
-
Dubois J, Patriquin HB, Garel L, et al. Soft-tissue hemangiomas in
infants and children: diagnosis using Doppler sonography. AJR
1998;171:247-252[Abstract/Free Full Text]
-
Donnelly LF, Bisset GS III, Adams DM. Combined sonographic and
fluoroscopic guidance: a modified technique for percutaneous sclerosis of
low-flow vascular malformations. AJR
1999;173:655-657[Free Full Text]
-
Fishman SJ, Burrows PE, Leichtner AM, Mulliken JB. Gastrointestinal
manifestations of vascular anomalies in childhood: varied etiologies require
multiple therapeutic modalities. J Pediatr Surg
1998;33:1163-1167[Medline]
-
Sato M, Tanaka N, Sato T, Amagasa T. Oral and maxillofacial tumours
in children: a review. Br J Oral Maxillofac Surg
1997;35:92-95[Medline]
-
Waner M, Suen JY, Dinehart S. Treatment of hemangiomas of the head
and neck. Laryngoscope
1992;102:1123-1132[Medline]
-
Achauer BM, Chang CJ, Vander Kam VM. Management of hemangioma of
infancy: review of 245 patients. Plast Reconstr Surg
1997;99:1301-1308[Medline]
-
Enjolras O, Riche MC, Merland JJ, Escande JP. Management of
alarming hemangiomas in infancy: a review of 25 cases.
Pediatrics
1990;85:491-498[Abstract/Free Full Text]
-
Gorlin RJ, Kantaputra P, Aughton DJ, Mulliken JB. Marked female
predilection in some syndromes associated with facial hemangiomas. Am J
Med Genet
1994;52:130-135[Medline]
-
Sarkar M, Mulliken JB, Kozakewich HP, Robertson RL, Burrows PE.
Thrombocytopenic coagulopathy (Kasabach-Merritt phenomenon) is associated with
kaposiform hemangioendothelioma and not with common infantile hemangioma.
Plast Reconstr Surg
1997;100:1377-1386[Medline]
-
Enjolras O, Wassef M, Mazoyer E, et al. Infants with
Kasabach-Merritt syndrome do not have "true" hemangiomas. J
Pediatr
1997;130:631-640[Medline]
-
Enjolras O, Mulliken JB. The current management of vascular
birthmarks. Pediatr Dermatol
1993;10:311-313[Medline]
-
Ezekowitz RA, Mulliken JB, Folkman J. Interferon alfa-2a therapy
for life-threatening hemangiomas of infancy. N Engl J Med
1992;326:1456-1463[Abstract]
-
Barlow CF, Priebe CJ, Mulliken JB, et al. Spastic diplegia as a
complication of interferon Alfa-2a treatment of hemangiomas of infancy.
J Pediatr
1998;132:527-530[Medline]
-
O'Donovan JC, Donaldson JS, Morello FP, Pensler JM, Vogelzang RL,
Bauer B. Symptomatic hemangiomas and venous malformations in infants,
children, and young adults: treatment with percutaneous injection of sodium
tetradecyl sulfate. AJR
1997;169:723-729[Abstract/Free Full Text]
-
Wacker FK, Cholewa D, Roggan A, Schilling A, Waldschmidt J, Wolf
KJ. Vascular lesions in children: percutaneous MR imaging-guided interstitial
Nd:YAG laser therapypreliminary experience. Radiology
1998;208:789-794[Abstract/Free Full Text]
-
Waner M, Suen JY, Dinehart S, Mallory SB. Laser photocoagulation of
superficial proliferating hemangiomas. J Dermatol Surg Oncol
1994;20:43-46[Medline]
-
Boon LM, Fishman SJ, Lund DP, Mulliken JB. Congenital fibrosarcoma
masquerading as congenital hemangioma: report of two cases. J Pediatr
Surg
1995;30:1378-1381[Medline]
-
Hayward P, Orgill D, Mulliken J, Perez-Atayde A. Congenital
fibrosarcoma masquerading as lymphatic malformation: report of two cases.
J Pediatr Surg
1995;30:84-88[Medline]
-
Yakes WF. Extremity venous malformations: diagnosis and management.
Semin Interv Radiol
1994;11:332-339
-
Yakes WF, Rossi P, Odink H. How I do it: arteriovenous malformation
management. Cardiovasc Intervent Radiol
1996;19:65-71
-
Koeller KK, Alamo L, Adair CF, Smirniotopoulos JG. Congenital
cystic masses of the neck: radiologic-pathologic correlation.
RadioGraphics
1999;19:121-146[Abstract/Free Full Text]
-
Brown RL, Azizkhan RG. Pediatric head and neck lesions.
Pediatr Clin North Am
1998;45:889-905[Medline]
-
Godin DA, Guarisco JL. Cystic hygromas of the head and neck.
J La State Med Soc
1997;149:224-228[Medline]
-
Dubois J, Garel L, Abela A, Laberge L, Yazbeck S. Lymphangiomas in
children: percutaneous sclerotherapy with an alcoholic solution of zein.
Radiology
1997;204:651-654[Abstract/Free Full Text]
-
Cunningham MJ. The management of congenital neck masses. Am
J Otolaryngol
1992;13:78-92[Medline]
-
Fageeh N, Manoukian J, Tewfik T, Schloss M, Williams HB, Gaskin D.
Management of head and neck lymphatic malformations in children. J
Otolaryngol
1997;26:253-258[Medline]
-
Heether J, Whalen T, Doolin E. Follow-up of complex unresectable
lymphangiomas. Am Surg
1994;60:840-841[Medline]
-
Lille ST, Rand RP, Tapper D, Gruss JS. The surgical management of
giant cervicofacial lymphatic malformations. J Pediatr Surg
1996;31:1648-1650