Exploring The Potential Of Procedures That Address Venous Ulcer Etiology
- Volume 24 - Issue 1 - January 2011
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The complexity of venous ulcerations leads to prolonged healing and doubt. Clinicians have traditionally treated venous wounds with debridement, multi-layer compression dressings and skin grafts.
Most of the literature focuses on various topical ointments, the use of allogenic grafting, compression therapies, etc. Unfortunately, there is little research on addressing the etiology of venous wounds. Understanding and treating the etiology in all aspects of medicine is imperative in order to achieve a successful result.
Venous insufficiency is a condition in which veins do not adequately return blood back to the central system. In the lower extremity, both the superficial and deep vein systems of the legs utilize valves to ensure cephalad flow. The deep vein system also uses muscular contraction to assist in pumping the blood upward. A perforating vein is a vein that penetrates a fascial plane and may connect the superficial venous system to the deep vein system or connect greater saphenous veins to small saphenous veins.
Over time, various risks factors such as heredity, hormones, pregnancy and prolonged standing cause the smooth muscle in the vein’s wall to relax. When this occurs, there is an inability of the vein valves to approximate. In the legs, the normal flow opposes gravity. However, with insufficiency, the blood refluxes and backflow occurs to the ankles. In severe cases, blood pooling leads to edema, hyperpigmentation, loss of skin turgor and ulceration. An ulcer can also occur after a varicose vein opens and causes bleeding.
Consider a patient who presents with a venous ulceration. In most cases, these patients receive wound care and compression therapy. One does not usually perform an ultrasound. Ultrasound is crucial in finding out where the insufficiency lies and which veins lead to the ulceration. It is imperative that the physician or registered vascular technician evaluates both the deep vein and superficial vein systems for reflux. Just scanning the deep vein system for a thrombus would be incomplete and will not identify the pathology involved.
Direct attention to the lower extremities while the patient is standing. Evaluate the deep vein system, including the femoral, popliteal, tibial and peroneal veins, and look for the presence of a thrombus and reflux. In the superficial system, test the greater and small saphenous veins as well as anterior and posterior circumflex and perforating veins.
In general, one should utilize the following guidelines to identify insufficiency in the superficial system: a greater saphenous vein larger than 0.4 cm in diameter, longer than 0.5 seconds of reflux and a small saphenous or perforating vein larger than 0.3 cm in diameter and 0.5 seconds of reflux. If varicosities are present, one can follow the varicosities towards their tributary. This is called vein mapping.
With the presence of a venous ulcer, the ultrasonographer will be able to scan over the ulcer and trace it back to the insufficient vein. The ulcer is usually a direct extension from a superficial varicosity. However, the underlying etiology is a result of insufficiency of the superficial, deep or perforating vein system. By addressing the insufficient vein either through ultrasound guided chemical ablation or endovenous ablation, venous ulcerations heal on an average of four weeks barring that no infection is present.
Key Insights On Ultrasound Guided Chemical Ablation
Ultrasound guided chemical ablation is a treatment in which one injects a sclerosant into the refluxing vein. The two most common sclerosants are sodium tetradecyl sulfate (Sotradecol, Angiodynamics), which recently received FDA approval, and polidocanol (Asclera, Merz). Traditional saline injections are not strong enough to treat large veins and should be reserved for cosmetic spider and reticular veins only.