title: Polytetrafluoroethylene membrane (Gore Preclude Vessel Guard) for vessel protection during anterior lumbar surgery: a preliminary study in pigs.
abstract: METHODS
  The effects of implanting a polytetrafluoroethylene (PTFE) membrane (Gore Preclude Vessel Guard, WL Gore and Associates, Flagstaff, AZ) during anterior lumbar surgery were studied in a pig model.
  
  
  OBJECTIVE
  We investigated whether placement of a PTFE membrane between the great vessels and anterior surface of the lumbar spine would minimize adhesions.
  
  
  BACKGROUND
  Anterior lumbar procedures continue to increase, as do revision operations. Anterior approaches remain challenging, however, because of the considerable risk of vascular injury. The risk is especially high with revision procedures because of the presence of adhesions that can hinder visualization and mobilization of vessels. Use of an anti-adhesion barrier may decrease the rate of vascular complications associated with revision surgery.
  
  
  METHODS
  Three spinal levels in 3 pigs were subjected to either discectomy, creation of a hole in the disc, or disc exposure only. In 5 of the 9 levels, a PTFE membrane was then implanted over the disc; the other 4 levels were controls. Spine segments were obtained 12 weeks later, and the tenacity of adhesions (scale of 0 to 4) and percentage of disc space covered by adhesions were assessed. The specimens were also studied histologically.
  
  
  RESULTS
  Mean values for adhesion tenacity were 2.75 for control spinal levels and 0.4 for levels with a PTFE membrane (P=0.008). Mean values for adhesion coverage were 81% for control disc spaces and 15% for spaces with a PTFE membrane (P=0.008). Histologic studies showed minimal adhesions, lack of an inflammatory reaction, and vascularized connective tissue between PTFE membranes and the vena cava.
  
  
  CONCLUSIONS
  In a pig model, implantation of a PTFE membrane during anterior lumbar surgery decreased the tenacity and amount of adhesions observed at necropsy. Studies of the efficacy and safety of the PTFE membrane in clinical anterior lumbar surgery are warranted.
authors.affiliation: Department of Orthopaedic Surgery, Spine Unit 2, Bordeaux 2 Université, Bordeaux, France.
authors.forename: Stephane
authors.initials: S
authors.lastname: Aunoble
authors.forename: Yasser
authors.initials: Y
authors.lastname: Alsawad
authors.forename: Richard
authors.initials: R
authors.lastname: Meyrat
authors.forename: Julien
authors.initials: J
authors.lastname: Rigal
authors.forename: Jean Charles
authors.initials: JC
authors.lastname: Le Huec
mesh_terms: D000818:Animals; D005260:Female; D008159:Lumbar Vertebrae / Q000601:surgery*; D008161:Lumbosacral Region / Q000601:surgery*; D008567:Membranes, Artificial; D011138:Polytetrafluoroethylene; D012086:Reoperation; D013552:Swine; D000267:Tissue Adhesions / Q000517:prevention & control; D014652:Vascular Diseases / Q000517:prevention & control*
chemical_list: D008567:Membranes, Artificial; D011138:Polytetrafluoroethylene