title: Palmaz stent in the treatment of central venous stenosis: safety and efficacy of redilation.
abstract: OBJECTIVE
  To assess the safety and efficacy of redilation of central venous stents in a growing animal model.
  
  
  METHODS
  Palmaz stents were placed in the inferior vena cava (IVC) in 18 newborn lambs. After 5 months, vena cavography was performed. Those animals in which growth of the IVC adjacent to the stent and/or neointimal hyperplasia had resulted in a stenosis were considered candidates for redilation. Repeat vena cavography, intravascular ultrasound, and histologic examination were performed at 2 or 6 months.
  
  
  RESULTS
  A stenosis of > 20% was demonstrated in 13 animals. Redilation was performed, and a 50% mean increase in stent diameter was achieved. There were no immediate complications. Late complications included nonocclusive laminar clot (n = 2), and a bar of tissue dividing but not occluding the caval lumen (n = 1). Moderate neointimal hyperplasia occurred in all stents. Stent compression (unrelated to redilation) occurred in seven animals.
  
  
  CONCLUSIONS
  Palmaz stents can be redilated safely and effectively in an animal model of growing central veins.
authors.affiliation: Department of Interventional Radiology, Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins Medical Institutions, Baltimore, Md.
authors.forename: S O
authors.initials: SO
authors.lastname: Trerotola
authors.forename: G B
authors.initials: GB
authors.lastname: Lund
authors.forename: M A
authors.initials: MA
authors.lastname: Samphilipo
authors.forename: C A
authors.initials: CA
authors.lastname: Magee
authors.forename: J S
authors.initials: JS
authors.lastname: Newman
authors.forename: J L
authors.initials: JL
authors.lastname: Olson
authors.forename: J H
authors.initials: JH
authors.lastname: Anderson
authors.forename: F A
authors.initials: FA
authors.lastname: Osterman
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D002404:Catheterization; D003251:Constriction, Pathologic / Q000000981:diagnostic imaging / Q000473:pathology / Q000628:therapy; D011859:Radiography; D012756:Sheep; D015607:Stents / Q000009:adverse effects; D014682:Vena Cava, Inferior / Q000000981:diagnostic imaging / Q000254:growth & development / Q000473:pathology