Exploring The Potential Of Procedures That Address Venous Ulcer Etiology
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. With ultrasound guidance, inject liquid sclerosant or foam sclerosant (sclerosant mixed with air or CO2) into the insufficient vein. Foam has become widely accepted for its advantages. Foam solution makes more contact with the vein wall due to increased surface area properties, disperses quicker and stays in the vein longer than liquid. Furthermore, one can easily visualize and follow the solution on ultrasound during treatment. With sclerotherapy treatment, the chemical damages the vessel wall. The vein hardens and the body breaks it down. Larger and deeper veins will harden, thicken and shrink but may not disappear altogether. One does not directly inject the ulceration but rather the insufficient vein along its course. If one performs ultrasound chemical ablation alone, it will take a few treatments before treatment addresses the veins at the ulceration site. Accordingly, this method usually occurs after an ablative procedure. Only perform this treatment on the superficial and perforating vein systems. Do not inject the deep venous system.
A Closer Look At Endovenous Laser Ablation
Endovenous laser or radiofrequency ablation is a procedure that closes the long segment of the insufficient vein. First access the insufficient vein under the guidance of ultrasound. Through the access needle, insert a guide wire. Remove the needle and place a dilator and sheath over the wire and into the vessel. Remove the wire and the dilator, and leave the sheath in the vein. Proceed to instill a fiber optic laser or catheter for radiofrequency. Confirm the placement of the fiber or cathode exiting the end of the sheath. Be sure to avoid superficial/deep vein junctions by at least 1.5 inches. Then deliver anesthetic agents mixed with saline, creating what is known as a sea of tumescence. After administering adequate anesthetic, remove the sheath along with the laser and/or catheter while delivering laser energy or radiofrequency. One must apply enough laser energy or radiofrequency to the vein in order to create appropriate closure and stop the flow through the insufficient portion. After the procedure, the patient wears compression stockings and bandages over the ulceration for approximately one week. Follow-up with the patient includes the use of post-procedure ultrasound to confirm the success of the procedure (namely ensuring there is no deep thrombus) and mapping the vein to the ulcerated site. Perform traditional debridement and have the patient wear compression dressings for two weeks. After the two-week period, if the ulceration has not already healed, ultrasound guided chemical ablation may close any remaining branches of veins that have reflux flow. Do not inject sclerosant directly through the ulceration. It is imperative to treat any and all vessels leading to the ulceration but it is not necessary to treat all superficial vein structures if insufficiency is not present. Over the course of therapy, the ulceration will decrease in size and the vessels will become hardened. Perform injections every three to four weeks. Four to six sessions may be needed to complete the course of therapy. On ultrasound, these vessels will not be able to compress and there is no filling on color flow Doppler.