A Collagen-Based Coil for Embolization of Saccular Aneurysms in a New Zealand White Rabbit Model
David F. Kallmesa,
Naomi H. Fujiwarab,
Debbie Yuen2,
Daying Daia and
Shu-Tung Li2
a Department of Radiology, Mayo Clinic, Rochester, MN
2 Collagen Matrix, Inc., Franklin Lakes, NJ
b Department of Radiology, Kagawa Medical University, Kagawa, Japan

View larger version (125K):
[in a new window]
|
FIG 1. Subject 1, aneurysm packed with collagen-based coil (2-week sample).
A, DSA image, showing aneurysm cavity.
B, Radiograph, showing collagen coils after implantation (arrow). Radiopaque sizing markers range from 2 mm to 6 mm in diameter.
C, DSA image, immediately after coil implantation, demonstrating residual flow at the neck (short arrow) and in the body (long arrow) of the aneurysm cavity.
D, DSA image, 2 weeks after implantation, showing interval progressive aneurysm occlusion, with no residual flow in the aneurysm cavity.
| |

View larger version (118K):
[in a new window]
|
FIG 2. Subject 8, aneurysm packed with collagen coil (10-week sample).
A, DSA image, showing aneurysm cavity.
B, Radiograph, showing collagen coils after implantation. Loose packing was present in the aneurysm cavity (long arrow) with a loop of coil present in the parent artery distal to the aneurysm cavity (short arrow).
C, DSA image, immediately after coil implantation, demonstrating large amount of residual flow in the body of the aneurysm cavity. No compromise of flow existed in the parent artery distal to the aneurysm cavity.
D, DSA image, 10 weeks after implantation, showing interval progressive aneurysm occlusion, with no residual flow in the aneurysm cavity and a triangular neck remnant (long arrow). Flow remained unimpeded in the region of the coils in the distal parent artery (short arrow).
| |

View larger version (70K):
[in a new window]
|
FIG 3. Subject 3, aneurysm packed with collagen coil (2-week sample).
A, Histologic specimen showing the neck of the aneurysm covered by a thick layer of tissue consisting of nucleated cells (arrows). (Hematoxylin and eosin stain, original magnification x40.)
B, Histologic speciment showing dense blue staining indicates collagen deposition within the aneurysm cavity. Vascular channels are also present. (Trichrome stain, original magnification x100.).
| |

View larger version (164K):
[in a new window]
|
FIG 4. Subject 7, aneurysms packed with collagen-based coil (10-week sample). Histologic specimen showing the aneurysm cavity is filled with dense matrix and spindle cells. (Hematoxylin and eosin stain, original magnification x20.).
| |

View larger version (136K):
[in a new window]
|
FIG 5. Subject 5, aneurysms packed with platinum coil (2-week sample). Histologic specimen showing the aneurysm cavity is filled with unorganized thrombus. The thrombus in the dome is laminated, suggesting ongoing turnover of unorganized thrombus. (Hematoxylin and eosin stain, original magnification x20.).
| |

View larger version (154K):
[in a new window]
|
FIG 6. Subject 12, aneurysm packed with platinum coil (10-week sample). Histologic specimen showing the aneurysm cavity remains nearly completely filled with unorganized thrombus, with a small amount of loose matrix along the periphery (arrows). (Hematoxylin and eosin stain, original magnification x20.).
| |