Fig 3. Photomicrographs illustrating histologic coil compaction scoring. All sections were stained with H&E.

A, Representative section for neck compaction score = 3, showing the tissue across the aneurysm neck is convex to the aneurysm cavity (magnification x20).

B, Representative section for a neck compaction score = 2, showing the tissue at the neck is flat (magnification x60).

C, Representative section for a neck compaction score = 1, showing the tissue at the neck slightly concave to the aneurysm cavity (magnification x15).

D, Representative section for a neck compaction score = 0, showing the tissue at the interface between the aneurysm cavity and parent artery is markedly concave to the aneurysm cavity (magnification x15).