Fig 5. Common findings of occluded and recurrent aneurysms. Macroscopic views with coils protruding into the lumen vessel before (A) and after coil retrieval (B). Note that all coils are re-covered with neointima, which consists of smooth muscle (SM) cells (C) embedded in a collagenous matrix surrounded by a unique layer of NOS⁺ cells (D). Note polypoid filaments (pink arrows in A and E) observed at the neck of aneurysms, with a similar neointima organization (F). Sections are hematoxylin-counterstained (scale bar: 200 µm for C, D, and F; 40 µm for insets in C, D, and F).