title: GORE PRECLUDE MVP dura substitute applied as a nonwatertight "underlay" graft for craniotomies: product and technique evaluation.
abstract: BACKGROUND
  While watertight closure of the dura is a long-standing tenet of cranial surgery, it is often not possible and sometimes unnecessary. Many graft materials with various attributes and drawbacks have been in use for many years. A novel synthetic dural graft material called GORE PRECLUDE MVP dura substitute (WL Gore & Associates, Inc, Flagstaff, Ariz) (henceforth called "MVP") is designed for use both in traditional watertight dural closure and as a dural "underlay" graft in a nonwatertight fashion. One surface of MVP is engineered to facilitate fibroblast in-growth so that its proximity to the underside of the dura will lead to rapid incorporation, whereas the other surface acts as a barrier to reduce tissue adhesion to the device.
  
  
  METHODS
  A series of 59 human subjects undergoing craniotomy and available for clinical and radiographic follow-up underwent nonwatertight underlay grafting of their durotomy with MVP. This is an assessment of the specific product and technique. No attempt is made to compare this to other products or techniques.
  
  
  RESULTS
  The mean follow-up in this group was more than 4 months. All subjects have ultimately experienced excellent outcomes related to use of the graft implanted with the underlay technique. No complications occurred related directly to MVP, but the wound-related complication rate attributed to the underlay technique was higher than expected (17%). However, careful analysis found a high rate of risk factors for wound complications and determined that complications with the underlay technique could be avoided by assuring close approximation of the graft material to the underside of the dura.
  
  
  CONCLUSIONS
  MVP can be used as an underlay graft in a nonwatertight fashion. However, if used over large voids (relaxed brain or large tumor bed), "tacking" or traditional watertight closure techniques should be used. The underlay application of MVP is best applied over the convexities and is particularly well-suited to duraplasty after hemicraniectomy.
authors.affiliation: Department of Neurosurgery, University of California, Irvine, CA 92697, USA. echappel@uci.edu
authors.forename: E Thomas
authors.initials: ET
authors.lastname: Chappell
authors.forename: Laura
authors.initials: L
authors.lastname: Pare
authors.forename: Mohammed
authors.initials: M
authors.lastname: Salehpour
authors.forename: Marlon
authors.initials: M
authors.lastname: Mathews
authors.forename: Charles
authors.initials: C
authors.lastname: Middlehof
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D003399:Craniotomy / Q000379:methods*; D004388:Dura Mater / Q000601:surgery*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D019291:Skull Base / Q000601:surgery; D013526:Surgical Mesh / Q000009:adverse effects; D013530:Surgical Wound Infection / Q000453:epidemiology; D016896:Treatment Outcome; D055815:Young Adult