FIG 4. Subject 16, 24-week implantation.

A, DSA image obtained before embolization. The aneurysm is 5.4 x 4.9 x 12.2 mm (width x neck size x length).

B, DSA image obtained immediately after embolization depicts 90% occlusion with a single coil loop in the parent artery (arrow).

C, DSA image obtained before euthanasia and 6 months after coil implantation shows no change.

D, Three distinct regions were present at histologic analysis. The distal dome is filled with organized tissue (short straight arrows). The midportion of the dome demonstrates unorganized thrombus (long straight arrows). The neck region (curved arrow) shows persistent flow and probably coil compaction, which was difficult to identify at angiography (hematoxylin-eosin stain, original magnification x8.3).