From an anatomical point of view, recurrences at the saphenofemoral junction (SFJ) could result from various sources. For one, it could be caused by a recanalisation of an originally occluded great saphenous vein (GSV). Secondly, another vein in the junction region could take over the function of the GSV and dilate. A third variation is a – more or less successful – generation of a new vein. In the last case, a sufficient vein could be generated, an insufficient vein could arise, or an inadequate venous regeneration, so that a cluster of frail but incomplete vasculature remains (neovasculature).