Case report: description of a venous annulus of the external iliac vein

This report describes a case of a venous annulus of the left external iliac vein. Above the inguinal ligament the external iliac vein divides into two branches, which are interlinked by a communicating branch, forming two loops. The first loop is situated around the external iliac artery, the second loop is found between the communicating branch and the common iliac vein. Although variations of the external iliac vein have already been reported, we could not find any description which would match to our observation.