Alginate for Endovascular Treatment of Aneurysms and Local Growth Factor Delivery
Jean Raymonda,
Annick Metcalfea,
Anne-Cecile Desfaitsa,
Edith Ribourtouta,
Igor Salazkina,
Kevin Gilmartinb,
Gill Embryb and
Robert J. Boockb
a Interventional Neuroradiology Laboratory, CHUM Research Center, Notre-Dame Hospital, Montreal, Quebec, Canada
b Boston Scientific Corporation, Natick, MA
View larger version (29K):
[in a new window]
|
FIG 1. Illustration depicts groups of animals and experimental models. TGF, transforming growth factor; CaCl2, calcium chloride; PDGF, platelet-derived growth factor.
| |
View larger version (23K):
[in a new window]
|
FIG 2. In vitro and in vivo clearance of transforming growth factor-ß1.
A, Blocks of alginate containing transforming growth factor-ß1 were kept in vitro and removed after 10 min to 7 days. The remaining activity was measured by scintillation counting, and the results are expressed as percentages of control activity.
B, Blocks of alginate containing transforming growth factor-ß1 were inserted in experimental aneurysms and removed after 10 min to 7 days. The remaining activity was measured by scintillation counting, and the results are expressed as percentages of control activity of blocks kept in vitro for identical time periods. In vitro and in vivo, the clearance of transforming growth factor-ß1 occurred in two phases: an initial rapid clearance (slope a) and a second slower phase (slope b).
| |
View larger version (73K):
[in a new window]
|
FIG 3. Angiographic evolution after alginate embolization. Selected view carotid angiograms are shown.
A, Obtained immediately after intraoperative Gelfoam block embolization without growth factors.
B, Obtained 3 weeks after intraoperative Gelfoam block embolization without growth factors. Note progressive obliteration of residual lesion with time.
| |
View larger version (58K):
[in a new window]
|
FIG 4. Neointima formation after alginate embolization. Photographs of neointimal coverage of the neck of the aneurysm are shown.
A, Obtained 3 weeks after intraoperative alginate block embolization, "en face."
B, Obtained after axial section. Note thick neointima between arrows.
| |
View larger version (111K):
[in a new window]
|
FIG 5. Pathologic examination after alginate embolization.
A, Photomicrophotograp of axial section of canine lateral wall aneurysm obtained 3 weeks after endovascular alginate embolization. Alginate is seen as black material. The neck is covered by neointima of variable thickness. Some alginate covered with neointimal tissue protrudes inside the carotid artery (arrows) (hematoxylin and eosin; original magnification, x20). S, suture between carotid and aneurysm; a, carotid arterial wall; N, region of the neck of the aneurysm.
B, Photomicrograph of axial section of lateral wall porcine aneurysm obtained 3 weeks after endovascular alginate embolization. Note very thick neointima contiguous with fibrous replacement of clot surrounding alginate coils (Movat’s pentachrome stain; original magnification, x20). a, carotid arterial wall; N, region of the neck of the aneurysm; Alg, alginate within partially organized clot; S, suture between carotid and aneurysm.
| |
AJNR - American Journal of Neuroradiology