title: Use of stretch expanded polytetrafluoroethylene as a microvascular graft in a low-pressure situation.
abstract: OBJECTIVE
  Microvascular reconstruction is often limited by the availability and length of the pedicle. The harvesting of autologous vein grafts adds morbidity and may not provide a good match. Expanded polytetrafluoroethylene (ePTFE) grafts have been used routinely in macrovascular surgery. However, there are no conclusive data on the performance of small-diameter PTFE grafts for pedicle lengthening in free flaps in a low-pressure situation. In this study, we evaluated the efficacy of 3-mm diameter stretch ePTFE grafts to lengthen the venous pedicle of a free flap.
  
  
  METHODS
  Fifteen male New Zealand white rabbits were operated on under sterile conditions. Using an operating microscope, an epigastric flap was raised and the pedicle was exposed and dissected to its origin from the superficial femoral vessels. A segment of the vein of 1 cm to 3 cm was replaced with a stretch ePTFE graft. Microsurgical anastomoses were performed using 9-0 nylon sutures. Four weeks postoperatively, the flaps were raised again with the pedicles re-explored. The graft was then removed and examined histologically.
  
  
  RESULTS
  All the grafts demonstrated immediate patency. There were no cases of flap loss on the control side at 4 weeks postoperatively. When re-explored, the patent ePTFE grafts appeared to be covered by connective tissue. Light microscopy showed neoendothelialization with fibrovascular in growth.
  
  
  CONCLUSIONS
  From this study, we can conclude that 3-mm diameter stretch ePTFE grafts can be used successfully as an alternative to bridging autologous vein grafts in free-flap pedicles.
authors.affiliation: Division of Plastic Surgery, Department of Surgery, National University Hospital, Singapore. surv21@nus.edu.sg
authors.forename: Marcus T C
authors.initials: MT
authors.lastname: Wong
authors.forename: Jane
authors.initials: J
authors.lastname: Lim
authors.forename: Lim Thiam
authors.initials: LT
authors.lastname: Chye
mesh_terms: D000818:Animals; D001794:Blood Pressure / Q000502:physiology; D001807:Blood Vessel Prosthesis; D019917:Blood Vessel Prosthesis Implantation; D019544:Equipment Failure Analysis; D005268:Femoral Vein / Q000502:physiology / Q000601:surgery*; D008297:Male; D011138:Polytetrafluoroethylene; D011817:Rabbits; D013524:Surgical Flaps / Q000098:blood supply*; D013718:Tensile Strength
chemical_list: D011138:Polytetrafluoroethylene