title: Introducer curving technique to reduce tilting of transfemoral Gunther Tulip IVC filter: in vitro study.
abstract: BACKGROUND
  Severe tilting of Günther Tulip filter (GTF) may be associated with difficulty in retrieval.
  
  
  OBJECTIVE
  To determine if an introducer curving technique of GTF can decrease the tilting degree of GTF in a caval model.
  
  
  METHODS
  The model was constructed by placing Dacron grafts in bifurcated glass tubes. The study included three groups: Right Straight Group (G(1)), Left Straight Group (G(2)), and Left Curved Group (G(3)). In G(3), a 10-20° angle was curved on the metal introducer before insertion to decrease the angle between inferior vena cava axes and metal introducer (A(CM)). Before GTF was released, the distance between the caval right wall and the apical hook (D(CH1)), and A(CM) were measured. The tilt angle of GTF (A(CF)) was also measured.
  
  
  RESULTS
  In G(1), GTF apex tended to center compared to G(2) (59% vs. 36%, P < 0.01). In G(3), GTF apex tended to center compared to G(2) (71% vs. 36%, P < 0.01). The differences of A(CF) between G(1) and G(2) (2.66 ± 1.80 vs. 4.13 ± 2.07, P < 0.01) and between G(2) and G(3) (4.13 ± 2.07 vs. 2.39 ± 1.79, P < 0.01) were statistically significant. There were significant positive correlations between A(CM) and A(CF), whereas significant negative correlations were detected between D(CH1) and A(CF) in each group.
  
  
  CONCLUSIONS
  The oblique course of GTF delivery system relative to the axis of the cava causes filter tilt, and thus, curving the introducer prior to its introduction helps to reduce the filter tilt. We recommend a clinical study to determine whether the introducer curving technique improves filter centering and its retrievability.
authors: Department of Radiology, First Hospital of China Medical University, Liaoning, China.
authors: Liang
authors: L
authors: Xiao
authors: Man
authors: M
authors: Wang
authors: De-Sheng
authors: DS
authors: Huang
authors: Jing
authors: J
authors: Shen
authors: Jia-Jie
authors: JJ
authors: Tong
mesh_terms: D020878:Device Removal / Q000379:methods*; D066298:In Vitro Techniques; D011474:Prosthesis Design; D019919:Prosthesis Implantation / Q000379:methods*; D015641:Radiography, Interventional; D016306:Vena Cava Filters; D014682:Vena Cava, Inferior