Congenital Vascular Malformations
Chad Simon, MD
History and Classification
Among the most common congenital and neonatal abnormalities.
In the past sometimes confusing classifications were developed
Understanding of the various biological characteristics of vascular tumors has been impeded.
Misconception that most of these lesions spontaneously disappear within the first years of life.
As a consequence congenital vascular malformations were often misdiagnosed and left untreated.
Virchow and his student Wegener, in 1880, separated all vascular tumors into angiomas and lymphangiomas characterized as "simplex", "cavernosum", and "racemosum".
Mulliken and Glowacki , in 1982, developed a biological classification encompassing physical findings, clinical behavior and cellular kinetics.
They distinguished hemangiomas from vascular malformations with two main characteristics distinguishing each.
Usually are not present at birth, but become apparent within the first weeks of life
Show a rapid proliferation during the first two years of life, followed by a slow involution.
True tumors, with proliferation of the vascular endothelium
Present at birth, but may not be clinically evident.
Show proportionate growth in relation to the body volume and show no signs of spontaneous involution
Defect in vascular smooth muscle
Progressive dilation of vascular channels
Burrows, in conjunction with Mulliken, in 1983, further described malformations as either:
High flow - having a connection to the arterial or capillary system
Low flow - having a connection to the venous or lymphatic system.
High-flow vascular anomalies, such as arteriovenous fistulas and arteriovenous malformations, are traditionally addressed by means of transarterial embolization.
Low-flow malformations found to be solitary or combined in capillary, venous, or lymphatic vessels are successfully treated with sclerotherapy.
1988, 7th meeting of the International workshop on Vascular Malformations, Hamburg
Classification differentiates between truncular and extratruncular malformations
Whole body blood pool scintigraphy
Transarterial lung perfusion scintigraphy
Selective and Superselective angiography
Direct puncture (percutaneous) arteriography
Direct puncture (percutaneous) phlebography
Direct puncture (percutaneous) lymphaniography
3 non-invasive tests are sufficiently accurate and obviate the need for invasive studies
Invasive procedures are usually reserved for treatment planning
Imaging modality most commonly used
Should include T1- and T2-weighted spin-echo imaging in multiple planes, fat-saturated T1-weighted imaging with the intravenous administration of a gadolinium-based contrast agent, and gradient-recalled echo (GRE) imaging.
T2-weighted images are used mainly to evaluate the extent of the abnormality.
GRE images are used to identify the hemodynamic nature of the condition (high- vs low-flow lesions); and contrast-enhanced images are used to determine the extent of the malformation and to distinguish low-flow vascular anomalies (venous malformation versus lymphatic malformation).
For any vascular anomaly, the basic approach is first, to evaluate fat-suppressed T2-weighted images to determine the extent of the anomaly, and second, to evaluate the GRE images to decide whether the anomaly is a high-flow lesion.
If the anomaly is a low-flow lesion, arteriovenous malformation, arteriovenous fistula, and hemangioma can be excluded from the differential diagnosis.
Low-flow vascular anomalies (venous malformation, lymphatic malformation, capillary-lymphatic-venous malformation) can be further differentiated on the basis of their morphologic appearances and contrast-enhancement patterns.
If the anomaly has no contrast enhancement or a minimal degree of peripheral contrast enhancement (rings and arcs), lymphatic malformation should be considered foremost in the differential diagnosis
If the anomaly has easily noticeable patchy areas of contrast enhancement, venous malformation should be suspected
If the lesion is a high-flow anomaly, In hemangiomas, fast-flow vessels are usually at the periphery of the mass, and the mass usually enhances homogeneously
A mass lesion is not expected in an arteriovenous malformation
If there are any remaining questions, the high-flow nature of an arteriovenous malformation can be easily confirmed with Doppler examination, which reveals high-flow, low-resistance arteries and an arterialized waveform in the draining veins.
Risk of high-output heart failure
Chronic venous hypertension
Lesion threatens vital functions
Persistent lymph leakage
Low flow malformations
Clusters of vesicles on the buccal mucosa, tongue, or conjunctiva.
The vesicles can be clear, red or black as a result of microscopic bleeding.
Macrocystic (cystic hygroma)
Almost a 50% association with chromosomal disorders such as Turner syndrome), trisomy 21, trisomy 18, and Noonan syndrome
Often located below the level of the mylohyoid muscle
Present as cervical cystic swelling, often with the overlying skin having a bluish hue
Since most lymphatic malformations are mixed-form malformations (macro- and microcystic), the most common therapeutic approach is sclerotherapy for the macrocystic portion of the malformation, then surgical excision of the remaining microcystic portion if needed
Aspiration or drainage results only in temporary shrinkage
Macrocystic lesions, if excised are ideally removed in one procedure, because repeated excisions are complicated by fibrosis and anatomic distortion
Microcystic lesions are often difficult to resect, because there are no distinct tissue planes between the malformed and normal structures
Lee, 2005, reviewed 315 patients treated for LM.
All head and neck LM were of the extratruncular form.
Sclerotherapy with OK-432 showed 90% success rate with macrocystic LM, but 50% with microcystic type
Jian, 2005, published a retrospective study to evaluate the results of Jian or Dingman glossectomy for lymphangiomatous macroglossia
Cosmesis and function improved after surgery in 7/7 patients. The tongue healed well, and the patients had no long-term complications.
The authors conclude that although partial surgical excision, injection of sclerosing solutions, electrocoagulation, and radiation have been the chief modalities of treatment of diffuse lymphangioma of the tongue, surgical management is the most effective treatment.
FIGURE 2. Case 4: A 9-year-old boy with lymphangiomatous macroglossia managed by Jian glossectomy preoperative and postoperative frontal and lateral views.
A, Frontal view preoperatively.
B, Lateral view preoperatively.
C, Frontal view postoperatively.
D, Lateral view postoperatively.
2/3 of all vascular malformations.
Are low-flow lesions.
Present in a spectrum, ranging from an isolated skin varicosity or localized spongy mass to complex lesions infiltrating various tissue planes
May occur in the craniofacial skeleton, most commonly in the mandible
The VM is a soft, compressible nonpulsatile mass with rapid refilling.
Expansion will occur on compression of the jugular vein or Valsalva's maneuver
Treatment algorithm proposed by Yao et al, 2001
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tag：vascular anomalies,vascular smooth muscle,vascular tumors,rapid proliferation,neonatal abnormalities,lymphangiomas,vascular malformations,vascular channels,venous malformations,arteriovenous malformations,angiomas,clinical behavior,biological classification,glowacki,involution,mulliken,fistulas,physical findings,introduction history,virchow