Endovenous Laser Ablation (also called Endovenous Laser Treatment, EVLT or EVLA) is a minimally invasive technique used to treat varicose veins. Using ultrasound guidance, a thin optical fiber is inserted into the diseased vein through a small incision. Laser energy is then delivered along the vein’s length, heating its interior and causing it to collapse and seal shut. Blood is rerouted through healthier veins. The procedure is done on an outpatient basis, involves little discomfort, and allows rapid return to normal activities.