A novel fish skin graft for dura repair: a comparative study in ovine

Closure of dura defects is crucial to maintain the functional abilities of the dura and prevent complications. Collagen-based grafts cause no strong foreign body reactions, being replaced by connective tissue over time. Collagen-based xenografts of bovine, porcine or equine origin are widely used but some have inherent religious barriers. The aim of this study was to assess the safety and efficacy of a collagen-based fish skin graft from Atlantic Cod for dura repair. We compared an intact fish skin graft to an established bovine collagen graft for dura repair in 24 adult Icelandic domestic sheep. Bilateral frontoparietal craniotomies were performed with iatrogenic dura defects, applying the two grafts, one on each side. The animals were euthanized at given endpoints of either two, six, twelve or twenty weeks, and macroscopic and histological examination was performed. No animal died or had any neurological abnormalities, signs of infection, or cerebrospinal fluid leakage. Greater early inflammation with earlier graft organization was observed with the fish skin graft, and acceptable inflammatory reactions without foreign body reactions with both grafts at twenty weeks. Both grafts were fully absorbed, and the dura restored. The intact fish skin graft is an ideal dural substitute, serving as a temporary anatomical barrier before fully degrading and promoting neodura formation. Standardizing the graft thickness could improve its efficacy. The graft is safe for use in dura repair and similarly effective as an established collagen graft. A human clinical trial is possible at this stage.