NonThermal vein closure is a brand new category of vein treatment which uses novel, heatless technology to seal diseased veins. Previously available only outside the U.S., NonThermal is now FDA-approved and available at Northwest Vein Center. This is innovative vein treatment is different than radiofrequency and laser vein ablation procedures which generate intense heat to close veins. While heat is a very effective method of vein treatment, it requires tumescent anesthesia (numbing medicine) to prevent thermal injury, and for this reason it is necessary to inject medicine into the leg when performing radiofrequency and laser vein ablations. There is mild discomfort associated with the needle punctures and a small risk of thermal injury. With NonThermal’s heatless technology, there is no need for tumescent anesthesia and zero risk of thermal damage. The benefit is a more comfortable procedure with less needle sticks and decreased risk. Patients may experience less soreness, less bruising and may not even need to wear stockings after the procedure.


NonThermal’s mechanism of action features chemical energy to seal veins, and there are three different NonThermal procedures available in the U.S. The first is Venaseal, a cyanoacrylate polymer which is placed in the diseased vein segment via a small catheter. The polymer adhesive instantly seals the vein upon contact with blood. Cyanoacrylate is already in widespread use for other applications elsewhere in the body, and the Venaseal polymer has been specially engineered for vascular use. The second vein procedure, ClariVein, is a cleverly designed mechanical catheter that features a rotating tip combined with a drug delivery port. The tip rotates at 3500 RPM, essentially a micro-sprinkler, spraying sclerosant medication 360 degrees inside the vein while also scratching the vein’s inner lining allowing the medication to further penetrate. Sclerosant medication acts as an irritant on the vein wall causing disruption and shrinkage. The chemical action is enhanced by the mechanical action of the tip and results in vein sealing. Our patients have reported a feeling of vibration during the procedure which is not uncomfortable. The third NonThermal, Varithena, is a foam medication which is injected into the vein, causing it to collapse. The procedure is elegant in its simplicity, and while injection therapy is not new, Varithena’s proprietary formula is unique with stable microbubbles which make the medication highly effective. Due to this advancement, much larger veins such as the saphenous vein can be treated unlike standard injection therapy.

Vein Treatment Results

Excellent results for the three NonThermal treatments have been demonstrated and published in scientific journals. In these studies, NonThermal is just as effective as radiofrequency and laser ablation with low complication rates. Despite this development, health insurance plans have been slow to adopt coverage for NonThermal, which is often the case with new medical procedures. Note that most insurance plans already provide coverage for radiofrequency and laser vein ablation procedures. As more people become familiar with NonThermal closure, it will likely become the vein procedure of choice and the future of vein treatment.

Safe Vein Treatment

In summary, NonThermal is a safe, effective FDA-approved procedure that is available today. If you are considering vein treatment, Northwest Vein Center encourages you to explore NonThermal treatment. All three NonThermal technologies, as well as radiofrequency and laser ablation are available at our Vein Center. Our board-certified surgeons will go over the procedures, help explain the differences and discuss the procedure that is best suited for you.