title: Analysis of ureteral stent compression force and its role in malignant obstruction.
abstract: OBJECTIVE
  Extrinsic ureteral obstruction can be a challenging entity for the urologist since half of the ureteral stents placed for malignant obstruction fail. We evaluated the resistance to radial compression of various stents.
  
  
  METHODS
  Silhouette(R) 4.6Fr, 6Fr and 8Fr, Sof-Curl Tecoflex 6Fr, Resonance 6Fr, Polaris Ultra 6Fr and 7Fr, and Percuflex 6Fr and 8Fr stents were tested. The force needed to compress the stent to 50% of its original external diameter was measured at 3 locations along the stent length, including proximal, middle and distal. Statistical analysis was performed.
  
  
  RESULTS
  Statistically greater force was required to compress the Resonance and Silhouette stents compared to all others tested. These results were maintained at all 3 locations along the stent. Only the Polaris 6Fr stent differed in resistance to compression along the stent length.
  
  
  CONCLUSIONS
  The significantly higher forces required to compress the Resonance and Silhouette stents may translate into improved success in patients with malignant ureteral obstruction.
authors.affiliation: Department of Urology, Naval Medical Center San Diego, San Diego, California, USA.
authors.forename: Matthew S
authors.initials: MS
authors.lastname: Christman
authors.forename: James O
authors.initials: JO
authors.lastname: L'esperance
authors.forename: Chong H
authors.initials: CH
authors.lastname: Choe
authors.forename: Sean P
authors.initials: SP
authors.lastname: Stroup
authors.forename: Brian K
authors.initials: BK
authors.lastname: Auge
mesh_terms: D008422:Materials Testing; D011474:Prosthesis Design; D015607:Stents; D013314:Stress, Mechanical; D014513:Ureter; D014517:Ureteral Obstruction / Q000209:etiology*