FIG 1. Axial photomicrographs show histologic findings 3 months after embolization. h indicates cyanoacrylate; c, coils; ca, carotid artery; n, neck; ra, recurrent aneurysm; vp, venous pouch; t, vascularized fibrous tissue. (HPS, original magnification x20).

A, Lateral wall aneurysm, obtained after embolization with cyanoacrylate-coated sponge. Aneurysm remains obliterated by a thick and fibrous neointima.

B, Lateral wall aneurysm, obtained after embolization with sponge alone. Aneurysm shows large recurrence and hypertrophy of the venous pouch.

C, Bifurcation aneurysm, obtained after embolization with coils alone, shows recurrence around the mass of coils. Neointima is thin and incomplete at the neck. Coils are embedded in vascularized fibrous tissue.

D, Bifurcation aneurysm, obtained after embolization with coils and cyanoacrylate, shows no recurrence. Note aneurysm filled with cyanoacrylate.