Venous Malformations

1. Essentials of Diagnosis

• Usually present at birth, but not detected As they become apparent, venous malformations are bluish-purple in color, raised, and are easily compressible Enlarge when dependent
• Gradually dilate, giving the a appearance of a growing lesion

2. General Considerations
VMs located in the head and neck and those located in an extremity, although histologically similar are, for practical reasons, usually thought of separately. Likewise, a VM present as a component of a syndrome, should be considered separately.

3. Pathogenesis
Some venous malformations occur in families and are inherited in an autosomal dominant fashion. This occurrence has been mapped to chromosome 9q. Blue Rubber Bleb Nevus Syndrome (cutaneous venous malformations associated with gastrointestinal bleeding), may be genetically similar.

4. Clinical Findings
Craniofacial venous malformations cause symptoms dependent on location. They are almost always a cosmetic problem and thrombosis often makes these lesions painful, impairing basic activities. MRI scanning is the single best modality to evaluate the three dimensional complexity of a craniofacial venous malformation. A percent of the patients will also have intracranial involvement and, therefore, the initial study should always include MRI of the brain. Coagulation studies should be done, as these patients often have low-grade disseminated intravascular coagulopathy. This typically requires no therapy.

5. Differential Diagnosis

• Can be confused with a "deep" hemangioma, although an MRI should easily differentiate Blue Rubber Bleb Nevus Syndrome - The effected patients have multiple cutaneous venous malformations and also have sometimes problematic gastrointestinal bleeding from intestinal lesions. Maffucci Syndrome - A syndrome of multiple venous malformations associated with enchondromas, beginning in adolescence. The skeletal lesions often degenerate into malignancy.
• Glomangiomas - The solitary type is the most common and is characterized by five classic symptoms: severe pain seemingly out of proportion to the lesion; localized tenderness; sensitivity to cold; ability to localize pain to pinpoint (Love's sign); and painful symptoms abolished by a proximal tourniquet (Hildreth's Sign).

6. Complications
Rapid growth is usually secondary to hemorrhage, and hematoma formation secondary to even minimal trauma.

7. Treatment
A patient with an extremity venous malformation that is able to wear a compressive garment may avoid the long-term morbidity of chronic engorgement. This is a first line therapy for extremity lesions, especially simple lesions (benign varicose veins) and lesions of a combined nature like Klippel-Trenaunay syndrome (a capillary malformation which overlies a deep venous and or lymphatic malformation of the extremity).

Sclerotherapy is the mainstay of treatment for craniofacial lesions and for extensive extremity lesions.2 Sclerotherapy is effective for these lesions because the sclerosant will stay in the lesion or can be made to stay in the lesion with compression of the outflow pathway. Alcohol-based sclerosants are the most typically used type of sclerosant. The sclerosant, in any formulation is intended to do extensive endothelial damage, to induce clotting and eventual vascular obliteration. Alcohol can cause skin necrosis.

Laser treatment can be used in certain instances. The goal of laser therapy is also to cause sufficient endothelial injury, which will lead to coagulation and partial resolution. Percutaneous laser use avoids damage to the skin. It may be that this is most helpful at the lip vermilion and for the intraoral component of larger lesions.3 Surgical therapy of these lesions is generally reserved for resection of previously sclerosed areas for improved cosmetic appearance or for lesions that respond poorly to sclerosant therapy.

Surgical therapy may also be necessary for dental malocclusion or other secondary problems after primary sclerosant management

Generally, the type of treatment will depend on the depth of the lesion, its location, and its extent of involvement A superficial venous malformation, or the superficial component of a compound venous malformation should be treated with a Nd:YAG laser since the vessels that make up a venous malformation are generally large. This laser, more than any of the others has the highest risk of complications. However, in experienced hands, it's a safe and effective laser. Generally, 2 or sometimes 3 lasers treatments, 6-8 weeks apart, are necessary.

Immediately after treatment, the area swells considerably but this resolves within 5-6 days with little or no pain. Complications include whitening of the skin, (hypopigmentation), temporary darkening of the skin (hyperpigmentation), and scarring. Remember, laser treatment only takes care of the superficial component. A lesion with a deep component therefore needs to be surgically removed. Venous malformations are the most difficult to remove. They involve large areas of tissue and bleed more than any other lesion during surgery, since they are made up of a large number of dilated vessels with very thin walls. It may also be necessary to sacrifice certain structures such as muscle and skin since they are frequently involved. A thermoscalpel is used to remove this type of lesion to minimize the risk of bleeding and here, more than with any other type of lesion, it's important that the surgeon be skilled in the removal of this type of lesion.

Sclerotherapy is very useful, especially in very extensive lesions or in lesions involving limbs. It's important to have a skilled interventional radiologist do the procedure since many complications may result. Multiple treatments are often necessary and the results vary depending on the skill of the radiologist. Since one can't cure the lesion with this technique, our intention is to control it with interventional radiology.