Figure 2. A 62-year-old woman (patient 2). (a) Venography of the left lower extremity showed a long segmental obstruction from the common iliac vein to the femoral vein. The right iliac veins fill via extensive collateral veins. (b) After the Gunther tulip retrievable vena cava filter was implanted at the inferior vena cava with an approach from the right jugular vein (arrowhead), catheter-directed thrombolysis using 120 000 IU urokinase was performed via the catheter inserted from the left femoral vein. Multiple side holes of the catheter tip were positioned in the segment of the thrombus (arrows). (c) Venography obtained immediately after procedures with interventional radiology, including catheter­directed thrombolysis, percutaneous transluminal angioplasty and self­expandable metallic stent placement, showed good venous blood flow of the left lower extremity. (d) Venography of the left lower extremity performed 14 days after the first treatment with an interventional technique showed re­obstruction of the treated region. In spite of further treatments such as systemic thrombolytic and anticoagulation therapy, post­stent percutaneous transluminal angioplasty, and mechanical thrombectomy performed thereafter, this obstruction was not relieved. The Gunther tulip retrievable vena cava filter was left as a permanent filter. Note that the implanted self­expandable metallic stent is shown (arrow).