Veins act as being the return path for blood which includes delivered oxygen and nutrients to human body tissues. Just after this exchange happens while in the capillaries, veins carry the oxygen-depleted blood again to the center and lungs for reoxygenation. Endovenous ablative therapy: Ablation of incompetent veins utilizes thermal energy https://sgvasculargrp.com/medical-condition/varicose-spider-veins/