title: Epineurial sheath tube (EST) technique: an experimental peripheral nerve repair model.
abstract: OBJECTIVE
  Here we present the epineurial sheath tube (EST) technique as a modified microsurgical rat sciatic nerve model. The EST technique provides a cavity or pouch consisting of an outer epineurial sleeve that has been freed from nerve fascicles. This cavity  may be appropriate to test the effectiveness and biocompatibility of implanted growth factors, cell suspensions (embedded in solutions or gels), or bioartificial nerve guide constructs.
  
  
  METHODS
  A total number of 10 rats underwent the surgical procedure for the EST technique. Cylinders  made of fibrin gel served as implants and place-holders. Three animals were euthanized directly after operation, while the others survived for 6 weeks. After immersion fixation (3·9% glutaraldehyde), both conventional histology [semi-thin sections (1 μm), toluidine blue] and scanning  electron microscopy were performed.
  
  
  RESULTS
  Conventional histology and scanning electron microscopy of samples that had been fixed directly after the surgical procedure displayed the integrity of the closed epineurial tube with the fibrin cylinder in its center. Even after 6 weeks,  the outer epineurium was not lacerated, the stitches did not loosen, and the lumen did not collapse, but remained open.
  
  
  CONCLUSIONS
  The practicability of the EST technique could be verified regarding feasibility, reproducibility, mechanical stability, and openness of the lumen. The  EST technique can be adapted to other nerve models (e.g. median or facial nerve). It provides a cavity or pouch, which can be used for different neuroscientific approaches including concepts to improve the therapeutic benefit of autologous nerve grafting or therapies to be used as an alternative  to autologous nerve grafting.
authors.affiliation: Burn Center, University Hospital Aachen, RWTH, Aachen, Germany. abozkurt77@gmx.de
authors.forename: Ahmet
authors.initials: A
authors.lastname: Bozkurt
authors.forename: Sebastian E
authors.initials: SE
authors.lastname: Dunda
authors.forename: Dan
authors.initials: D
authors.lastname: Mon O'Dey
authors.forename: Gary A
authors.initials: GA
authors.lastname: Brook
authors.forename: Christoph V
authors.initials: CV
authors.lastname: Suschek
authors.forename: Norbert
authors.initials: N
authors.lastname: Pallua
mesh_terms: D020341:Absorbable Implants / Q000639:trends*; D000818:Animals; D048091:Guided Tissue Regeneration / Q000379:methods*; D009416:Nerve Regeneration / Q000502:physiology; D019635:Neurosurgical Procedures / Q000379:methods*; D010525:Peripheral Nerves / Q000502:physiology / Q000601:surgery* / Q000648:ultrastructure; D051381:Rats; D011917:Rats, Inbred Lew; D012584:Sciatic Nerve / Q000502:physiology / Q000601:surgery* / Q000648:ultrastructure; D020426:Sciatic Neuropathy / Q000473:pathology / Q000503:physiopathology / Q000601:surgery*