Tissue response of a small saccular aneurysm after incomplete occlusion with a Guglielmi detachable coil

Abstract

A 49-year-old woman had a small saccular aneurysm that was incompletely occluded with a Guglielmi detachable coil (GDC). She died from rupture of another aneurysm 42 days after the treatment. Autopsy for the embolized aneurysm revealed no neoendothelium at the aneurysmal neck, but an organized thrombus was observed limited to the periphery of the aneurysmal lumen. Although isolation of the aneurysm was not apparent, loose embolization with this method may help to reinforce the aneurysmal wall.

fig 1.

A 49-year-old woman with a small saccular aneurysm. A, Anteroposterior carotid angiogram shows the PTA (arrow) and a small saccular aneurysm at the basilar-superior cerebellar bifurcation (arrowhead). B, Angiogram, after embolization with a GDC, shows partial opacification of the fundus of the aneurysm.

fig 2.

Microscopic examination of the small saccular aneurysm after GDC occlusion. A, Low-power photomicrograph shows a cross-section of the aneurysm at the fundus, with a fibrotic component (small star) adjacent to the aneurysmal wall (arrows) and an unformed thrombus at the center of the aneurysm (large star). The location of the coil is indicated (asterisk). (Azan stain; magnification ×100) B, Higher power magnification of the region adjacent to the wall shows fibrous connective tissue with rich capillaries. (Azan stain; magnification ×200)