FIG 3. Number 15 aneurysm in HydroCoil group, 6-week implant.

A, Anteroposterior DSA of the brachiocephalic artery shows a wide-necked aneurysm.

B, Anteroposterior DSA obtained immediately after embolization with HydroCoils shows the aneurysm is nearly completely occluded.

C, Anteroposterior DSA obtained 2 weeks after embolization shows the aneurysm remaining stable.

D, Hematoxylin and eosin stain; original magnification, x1.1. Coronal section obtained through the aneurysm cavity. No substantial inflammatory response is present. Microcompaction is absent. A small part of persistent unorganized thrombus is shown in the aneurysm dome.

E, Hematoxylin and eosin stain; original magnification, x10. Magnification of the area shown in panel D. Cellular fibrous tissue is shown across the neck.