Development of biologically active GDC for the treatment of cerebral aneurysms.

In Vitro Study: The surface of polystyrene dishes were treated either by: 1) collagen coating without ion implantation, or 2) collagen coating with ion implantation. Ne(+) implantation was performed on area 2 with fluences of 1 x 10(15) at an energy of 150 keV Bovine endothelial cells were cultured on the dishes and the resistance to detachment of cells was evalated with trypsin treatment. Experimental Aneurysm Study: GDCs were coated with either type I collagen, fibronectin, vitronectin, laminin or fibrinogen. Ion implantation was then performed on these protein-coated GDCs. 56 experimental aneurysms were constructed microsurgically in the bilateral common carotid arteries of 28 swine. The aneurysms were embolized with standard GDCs or with ion-implanted protein-coated GDCs. The animals were sacrificed at day 14 after coil placement. The aneurysmal orifice was observed microscopically. In vitro study showed that endothelial cell proliferation and strength of cell attachment were accerelated by ion implantation. On specimens examined 14 days post-embolization, greater fibrous tissue coverage at the neck of the aneurysm was observed macroscopically and microscopically with ion implanted GDCs, whereas only a fibrin-like thin layer covered the standard GDC surfaces. These in vitro and in vivo studied indicate that ion implantation combined with protein coating of GDCs improves cellular adhesion/proliferation. This technology may provide an improvement in clinical outcome of cerebral aneurysms.