The Office based (OB) – CHIVA (Conservative and Hemodynamic treatment of Venous Insufficiency in Outpatients) is a slightly modified CHIVA strategy designed to use some technical facilities adopted in ablative procedures. Currently available choices for CHIVA crossotomy are: section ligature, isolated ligature, the clip and the triple saphenous flush ligation (TSFL) technique. The OB-CHIVA was introduced in order to reduce the required resources and generic surgical risk, especially risks associated with CHIVA crossotomy. In addition, OB-CHIVA tries to answer the often faced but never solved issue of a minimally invasive surgical CHIVA intervention. It is not only a technical but rather a conceptual variation of CHIVA, thus the two methods cannot be considered the same thing. The essential difference is the reduced length of saphenous treatment, which is much shorter than the length generally treated in laser procedures. Unlike CHIVA but similar to LASER and RF, OB-CHIVA leaves some tributaries of the arch and uses them as washing vessels (draining crossotomy). The research protocol includes only OB-CHIVA cases with crossotomy performed with alternative methods (LASER, RF, and steam). Chemical agents were excluded. The prerequisite for treatment is SFJ terminal valve incompetence; thus, we need to know: i) whether the GSV reflux is deviated or not (Shunt I) towards at least one incompetent tributary; and ii) if the latter is the case, does the GSV trunk reflux disappear while pressing the tributaries with a finger? (positive reflux elimination test [RET]+, Shunt III) Or not? (negative reflux elimination test [RET]-, Shunt I+II). For Laser draining crossotomy, the tip of the LASER fiber is placed at the end of the last washing tributary, at a variable and personalized distance from the junction worth SFJ-free cm and one variable and personalized L length segment is treated until the first draining tributary. In the fixed variant of the procedure, starting as described after the last washing vessel, a fixed 7 cm length of the trunk is treated instead. For radio frequency draining crossotomy, the electrode at the tip of the catheter is 7 cm long, though a new available electrode provides a length of 3 cm. Though it is a fixed length procedure, the choice of the smaller electrode could fit a detailed length to be treated. Steam draining crossotomy is at present only a fascinating hypothesis while mechanical draining crossotomy is a good candidate to compete with LASER for its precision. Tributary disconnection can be performed classically by a flush phlebectomy, which is already an ambulatory/office quick procedure. Also, LASER and foam can be used with different effects. Devalvulation of a competent trunk GSV valve, if requested, may be performed during a flush phlebectomy or may be wire guided, using a 18 gauge needle, a wire guide, and a dilatator, generally included in the catheter kit. A follow-up examination will be performed soon after the procedure at 1-week, 1-month, 6 months, 1-year, and 2-years.