Porcine small intestinal submucosa as a dural substitute

BACKGROUND The continuing search for the ideal dural substitute is currentl y directed toward collagen preparations. Xenogeneic porcine small intestina l submucosa (SIS), a naturally occurring extracellular matrix rich in colla gen, has been successfully used as a soft tissue graft in several body orga n systems, including preliminary studies as a dural substitute in the rat. METHODS Eight dogs underwent temporoparietal craniotomy and dural resection with replacement by SIS. Five dogs had contralateral procedures without SI S grafting. Three dogs had contralateral SIS grafts placed 2 months after t he initial procedure. Histologic assessment was obtained at 7, 30, 60, 90, and 120 days. Cerebrospinal fluid (CSF) cytological examination and routine serum chemistry preceded sacrifice. RESULTS Histologic evaluation showed initial graft infiltration by mononucl ear round cells, spindle-shaped cells within an eosinophilic staining extra cellular matrix, and neovascularity. Complete resorption of the graft was e vident by 60 days. This pattern is consistent with the previously described incorporation and remodeling of the SIS graft at other sites. CSF cytology and routine serum chemistry at the time of sacrifice were normal. Response to repeat grafting was identical to that of initial exposure. There was no clinical or histologic evidence of sensitization or graft rejection. No ev idence of adverse effect on the underlying cerebral cortex was observed. CONCLUSIONS Porcine small intestinal submucosa demonstrates a favorable bio logic response as a dural substitute in the canine model. It is a promising biomaterial for dural replacement. (C) 1999 by Elsevier Science Inc.