Vascular Malformations
Capillary Malformations (Port-Wine Stains)
One can think of these as a vascular malformation of the tiniest blood vessels in the body occurring in the most superficial layer of viable skin, called the dermis layer. They are a deep red to purple in color and can occur anywhere on the body. Like all other vascular malformations, these are present at birth and tend to grow throughout the lifetime of the patient with thickening of the affected portion of the skin and darkening of the primary color. These changes are partially attributable to the chronic local inflammatory changes that take place as a result of the malformation.
Capillary malformations can either be isolated or associated with other, more extensive syndromes, particularly when a specific pattern of distribution is noted. Syndromes associated with capillary malformations include Klippel-Trenaunay Syndrome, Parkes-Weber Syndrome, and Sturge-Weber Syndrome. In these cases, a dedicated search to identify vascular malformations in other organs is necessary so as to prevent potentially devastating complications of untreated lesions.
The first-line of treatment for problematic capillary malformations is laser therapy via a pulsed dye laser. Multiple treatments are often needed. Results vary depending on location of the malformation with the general rule of thumb being that central lesions (face, head, neck) fare better than more peripheral lesions (hands and feet). Early treatment is encouraged to optimize results prior to more extensive chronic local inflammatory changes take place. These are relatively well-tolerated with minimal complications the most common of which is scarring from multiple treatments. As with all other vascular malformations, there is no cure for capillary malformations and recurrence is not an uncommon event. Treatment does not eliminate the lesion completely. In other words, laser therapy will not eliminate the associated discoloration but significant improvement is frequently achieved. Regular follow-up at designated intervals is required for optimal maintenance of therapy.
Slow-Flow Venous Malformations
Veins are blood vessels that carry blood from organs back into the heart and lungs for re-oxygenation. Under normal circumstances, the venous circulation is a low pressure system. Malformations affecting the venous circulation are, by far, the most common comprising nearly 75% of all vascular malformations. Venous malformations can either be isolated or part of a syndrome, most commonly Klippel-Trenaunay Syndrome. The cause is unknown although certain genetic mutations have been identified in patients with these malformations. Venous malformations can either be an isolated event in an individual sporadically or inherited from parents in a familial form. They are present at birth but do not become apparent until later in life when an external or internal stimulus such as activity, injury, puberty, pregnancy, surgery, etc. triggers symptomatic exacerbation of the malformation. They can happen anywhere in the body at any depth. Symptoms range from minor aches and pains to recurrent, life-threatening hemorrhage, clotting disorders, and organ damage, mostly within bones, joints, and skeletal muscles.
These lesions are readily identified on properly conducted MRI studies. Treatment primarily consists of Direct Stick Embolization or injection of a detergent-type compound directly into the venous malformation after delineation under ultrasound or x-ray. This treatment is generally well-tolerated if performed judiciously with focal treatments performed in multiple sessions dispersed over several sessions with appropriate length intervals in between sessions. Aggressive treatment of large areas can cause local skin and nerve damage, and heart and lung related problems.
Surgery is not an ideal first-line therapy for these lesions given the risk for bleeding and disfiguring results following resection of involved tissue planes. Surgery can, however, be very effective when performed in conjunction with sclerotherapy. This concept emphasizes the importance of close collaboration among treating physicians from various specialties. Moreover, the VAMP team features surgeons such as Dr. Nassiri and Dr. Gupta who have extensive training and expertise in both open surgery as well as minimally invasive, endovascular and interventional techniques. As a result, the most appropriate and effective treatment or combination of treatments is offered to the patient without limitation.
As with all other vascular malformations, treatment is geared towards controlling and minimizing symptoms. There is no absolute cure for these lesions. Multiple treatments are often necessary and recurrence is not uncommon. In general, focal, superficial lesions are more effectively treated than widespread, deep lesions.
Slow-Flow Lymphatic Malformations
Lymphatic vessels are channels that carry fluid existing outside of blood vessels (arteries and veins) back into the blood circulation. Similar to veins, they function in a low-pressure environment under normal circumstances. Malformations affecting the lymphatic channels can be secondary to an obstruction or a congenital deformity of the walls of the lymphatic channels themselves. This results in stagnant lymphatic flow and pooling of the lymph fluid into cysts or fluid-filled pockets of various sizes. These cysts can be bled into, become infected, or both. If large enough, they can cause problems by impinging upon and compromising the function of adjacent organs such as the aerodigestive tract. The limbs such as the legs and feet can also be affected although these can have variable patterns and timing of presentation.
Lymphatic malformations are congenital (present at birth). But unlike venous malformations or arteriovenous malformations, they become manifest much earlier in life, during infancy and early childhood because they are not as hormonally regulated as blood vessels are.
Diagnosis is made by ultrasound, MRI, and rarely CT scans depending on location and pattern of presentation. Most commonly, the first-line treatment is drainage of the cysts by a catheter followed by injection of the drained cyst cavity with a sclerosant (a detergent-like compound that causes irritation, inflammation, and gradual collapse of lymphatic cyst). This is most successful for larger cysts (those greater than 2 cm). Smaller cysts, called microcysts are more difficult to treat. Multiple treatment sessions may be required and recurrence is not uncommon.
Surgery as first-line treatment is generally not recommended as complication rates can be high. Surgery is best reserved for residual lesions after sclerotherapy or for smaller cysts not responding to sclerotherapy.
Laser therapy can also be offered for specific types of lymphatic malformations and their associated overlying skin changes.
High-Flow Arteriovenous Malformations
Arteriovenous malformations represent an abnormal connection between arteries (blood vessels that supply the body organs) and veins (blood vessels that drain the body organ). One can think of this as a short-circuit of sorts wherein blood pumped from the heart to a given organ is prematurely redirected away from that organ back towards the heart. This can create a vicious cycle of abnormal blood flow that deprives the affected organ from oxygen and nutrients and can take a toll on the circulatory system including the heart and the affected blood vessels. If severe enough, it can cause heart and/or organ failure.
As with all other vascular malformations, arteriovenous malformations are present at birth (congenital) but do not become problematic until later on in life as the malformation continues to grow with the patient and becomes affected by changes in the hormonal environment as well as activity and/or local trauma. By far, the most important factor in management of arteriovenous malformations is early detection and treatment.
Congenital arteriovenous malformations can be present anywhere in the body but have a predilection for the brain, spinal cord, and the extremities. Rarely arteriovenous malformations of the internal organs such as the kidneys, the intestines, and the lungs can be detected. Early referral to a dedicated center of excellence is key. Diagnosis will inevitably depend on a series of imaging studies such as ultrasound, MRI, and angiography. Treatment is almost always indicated to minimize symptoms and decrease the likelihood of expansion and organ loss. In some rare cases, the malformation has expanded severely enough such that treatment may provide little to no benefit and management is geared more towards palliation of associated symptoms.
The mainstay of treatment for arteriovenous malformation is catheter-based embolization. The term embolization refers to delivery of certain particles or substances as closely as possible into the focus of the arteriovenous malformation. These particles or substances will then act to shut down the malformation by disrupting the blood supply to the focus of the malformation and redirecting blood flow back into the normal circulation. Most commonly, multiple treatment session will be required throughout the lifetime of the patient. It is important to emphasize that there is no cure for arteriovenous malformations and that treatment is aimed at minimizing symptoms and slowing the progression of the disease. Even with successful treatment, certain severe cases can continue to expand and cause organ and/or life-threatening problems.
Surgery by and large is not recommended as primary treatment of arteriovenous malformations except in rare refractory cases or to treat associated complications of the malformation.
For a closer look at our affiliated brain aneurysm and arteriovenous malformation program, please visit www.rwjuh.edu/brainaneurysm/.
