Extracorporeal Flow Abolition in Relation With Primary Insufficiency of Great Saphenous Veins (GSV) Using High Intensity Focused Ultrasound (HIFU) Generated by Sonovein: A Multi Center Prospective Pivotal Study

Inclusion Criteria: * Candidate for venous procedure with primary GSV insufficiency involving reflux in the segment to be treated * CEAP-clinical classification ≥ 2 * Physical condition allowing ambulation after the procedure. * Agree to comply with the Clinical investigation plan and follow-up schedule of the study * Targeted tissue reachable for treatment with the device. * Age over 22 years at the time of enrollment. * No acute venous thrombosis. * No complete or near complete deep vein post-thrombotic disease. * Patient has signed and understood the written informed consent. Exclusion Criteria: * Patient is pregnant * Known allergic reaction to anesthetics to be used. * Legally incapacitated or imprisoned patients * Patient's vein target not clearly visible on the ultrasound images (in B mode) at the inclusion visit * Patient participating in another clinical trial involving an investigational drug or device. * Ankle-brachial index \<7 (ABI) * Undergoing active anticoagulant therapy within the last 6 months * Diameter of the treated anatomical segment below ≤ 2mm \& above \> 20mm * Patients where HIFU cannot be delivered to tissues where macro calcifications induce a significant shadow in the ultrasonic image * Patients where EPack must be put in contact with an ulcer * Patients with significant thick scars on the skin over the segment to be treated * Security distance respected in regards of : * nerves \& bones * the surrounding vessels * Patient who may not be considered as good candidates for treatment by the investigator outside the explicit exclusion criteria above listed