The Twist Technique: A Method to Minimize Wire Prolapse during Bird's Nest Filter Placement

Purpose To determine whether a twist technique can help reduce the occurrence of fine-wire prolapse proximal to the hooks of the Bird's Nest filter in the inferior vena cava. Materials and Methods Abdominal radiographs were retrospectively analyzed after placement of filters with no twist ( n = 100), with two 360° twists ( n = 55), or with three 360° twists ( n = 61). Results Prolapse of 5 mm or more was encountered in 32% of cases (32 of 100 cases) in which no twists were imparted. The average length of prolapse was 2.8 cm (range, 0.5–5.1 cm). The average length of the filter nest was 9.4 cm (range, 5.1–13.6 cm). Use of two 360° twists reduced the rate of prolapse to 9.1% (five of 55 cases) ( P P Conclusion Application of two or three 360° twists to the catheter-sheath unit during insertion of the Bird's Nest filter produces a statistically significant reduction in the occurrence of wire prolapse.