FIG 5. Light microscopic findings in region of aneurysm neck at day 14 after treatment, with standard GDCs (A, original magnification) or vitronectin GDC-Is (B, x10). Note intense fibroblast response with vitronectin GDC-I. Only a thin fibrous layer was observed with standard GDCs. Light microscopic findings in region of the aneurysm sac. Sac of aneurysm treated with collagen GDC-I was filled with fibroblasts and monocytes. No neovascularization was seen with collagen GDC-Is (C, x10), whereas microscopic neovascularization was seen in aneurysmal dome with standard GDCs (arrow, D, x10).