medical treatments
There have been tremendous advances in the medical treatment of hemangiomas and vascular malformations over the past five years. At the AVM Center of New York, we are fortunate to have Dr. Francine Blei as Medical Director. Dr. Blei is an internationally recognized authority in the field and has been at the forefront of research and the medical treatment of these conditions for over thirty years. She has authored many of the most important papers in the field, and is currently the Director of the Scientific Program for ISSVA (The International Society for the Study of Vascular Anomalies), the largest and most prestigious international organization devoted to the study and treatment of vascular malformations.
Hemangiomas were formerly just left alone on the assumption that they would eventually resolve on their own with no specific treatment. Large hemangiomas, however, can cause problems with bleeding, ulceration, and if in certain locations, can interfere with breathing, vision, or feeding. A major breakthrough has been the introduction of Propranolol, a drug which can dramatically accelerate the process of involution. Dr. Blei is an expert in managing local and systemic treatment for hemangiomas.
Research into the development of vascular malformations has resulted in recent breakthroughs in the understanding of the biology, molecular pathways, and genetics of AVMs. This knowledge has led to the introduction of several new drugs which show great promise in the treatment of these conditions. Dr. Blei is uniquely qualified to direct the medical treatment of children and adults, using the most up to date approaches.
Sclerotherapy
Sclerotherapy (sometimes referred to as direct embolization), consists of injecting a drug or other chemical agent directly into a low flow (venous or lymphatic) malformation in order to reduce its size and symptoms. The most common drugs include STS (Sotradecol, sodium tetradecyl sulfate), Polidocanol, other detergent‐type agents, Bleomycin, ethanol, and doxycycline. Each of these drugs has advantages and drawbacks – the choice of which one to use depends on the type of malformation, the anatomic location, the age and size of the patient, as well as other factors. The procedure is performed under a light general anesthetic and generally takes anywhere from thirty minutes to two hours, depending on the size and complexity of the malformation. The malformation is entered with a fine needle or catheter using a combination of guidance techniques, including prior MRI studies, ultrasound, and fluoroscopy (real‐time x‐ray imaging). Once the lesion has been entered, radiographic contrast is injected to outline the malformation and confirm correct positioning. The sclerosing agent is then injected, which causes clotting (thrombosis) within the lesion, as well as intentionally causing an inflammatory reaction which will result in shrinkage of the malformation over a period of weeks. Once the drug has been injected, a small amount of collagen is injected as the needle is withdrawn, to protect the overlying normal tissues. Lymphatic lesions are treated in a similar fashion, but larger cystic lesions may require initial drainage of the lymphatic fluid using a catheter.
Embolization
Embolization is the intentional blocking of an artery or vein for therapeutic purposes. The technique has been used in various medical and surgical situations for nearly fifty years, and was first used for the treatment of vascular malformations over thirty years ago. Embolization has now become the mainstay of treatment for vascular malformations in any part of the body, from the brain to the extremities. In high flow (arteriovenous) malformations, merely closing of the artery leading to the malformation has been shown to be ineffective, whether it is performed with surgery or coil embolization. The reason for this is that the human body has an extraordinary ability to use existing vessels or newly formed vessels (collaterals) to find their way back to the center of the malformation (the nidus). In fact, it has been shown experimentally that an AVM is the strongest stimulus for the development of collateral vessels in the body. The goal then, is to close the center of the malformation, thereby removing the stimulus for new vessels to develop. Given the complexity of some malformations, this is not always easy and in some cases the nidus cannot be eliminated completely, even though the clinical problem may be solved. The aggressiveness of the treatment must match the severity of the initial problem – in other words, we are treating the patient, not their x‐rays or MRI studies. This risk: benefit analysis is one of the most important skills required to provide the best possible result for any given patient.The AVM Center of New York is fortunate to have Dr. Robert Rosen as its Clinical Director, an interventional radiologist and endovascular surgeon who has specialized in AVM treatment for over 35 years and is recognized internationally as a leading authority in the field.
Surgery
For many years, it was felt that surgery was not advisable in treating hemangiomas and vascular malformations due to the risk of bleeding, scarring, loss of function, and the likelihood of recurrence. Surgery for these conditions requires very specific training and expertise, and is best performed by surgeons with experience in this area. Depending on the clinical problem, the appropriate specialist may be a plastic surgeon, vascular surgeon, orthopedic surgeon, or other subspecialist. The surgeons at the AVM Center of New York are highly specialized leaders in the field, and treat patients from around the world. Our Surgical Director is Dr. Milton Waner, probably the best known surgeon in the field, with the longest experience in dealing with hemangiomas and vascular malformations. The surgical approach to these patients is truly a combination of art and science. Surgical procedures range from removal of superficial malformations of the skin to extensive resections for bulky or deep seated lesions. All patients are evaluated by the multidisciplinary team prior to surgery, as the operation itself may be definitive or part of a larger overall treatment plan. The team has worked together for so many years that it is unusual for there to be any disagreement about the best possible treatment plan for any given patient.
Laser Treatment
Lasers are extremely useful in the management of both hemangiomas and vascular malformations. They are primarily employed to treat lesions which are confined to the skin, as laser energy generally cannot penetrate greater than one or two millimeters. Lasers are most commonly used to treat “port wine stains”, reddish or purplish birthmarks which are actually capillary venous malformations. These birthmarks tend to grow and darken over time, and it is now felt that early treatment will dramatically improve the long term result. The field of laser technology is rapidly evolving, and there are many types of laser available. The choice of the type of laser and the technique of performing the actual procedure will determine the outcome, and this requires considerable expertise. The physicians at the AVM Center of New York have been involved in the research and development of medical laser technology for many years, and have access to the most advanced devices available.