American Journal of Neuroradiology 26:2560-2568, November-December 2005
© 2005 American Society of Neuroradiology
INTERVENTIONAL
Histopathologic and Immunohistochemical Comparison of Human, Rabbit, and Swine Aneurysms Embolized with Platinum Coils
From the Neuroradiology Research Laboratory, Department of Radiology, Mayo Clinic, Rochester, MN
Address correspondence to David F. Kallmes, MD, Mayo Clinic, 200 First Street, SW, Rochester, MN 55905
BACKGROUND AND PURPOSE: The purpose of this study was to clarify the cellular mechanisms of aneurysmal healing by comparing histologic and immunohistochemical findings in experimental rabbit and swine aneurysms to a human aneurysm embolized with platinum coils.
METHODS: Swine sidewall aneurysms (n = 5, harvested at 12 weeks) and elastase-induced rabbit aneurysms (n = 6, harvested at 24 weeks) were created and embolized. A single human aneurysm, embolized 6 years before death, was harvested following autopsy. All specimens were processed by using a modified paraffin embedding technique. Tissue was sectioned and stained with hematoxylin and eosin and Masson trichrome. Immunohistochemistry and immunofluorescence were performed with multiple antibodies, including alpha smooth muscle actin, myosin heavy chain, desmin, vimentin, and CD31.
RESULTS: The human aneurysm’s dome was filled with loose, hypocellular, amorphous tissue. The aneurysm’s neck was completely covered with a thin layer of hypocellular tissue. Collagen and myofibroblasts were sparse in both the dome and neck. Rabbit aneurysms’ domes were also filled with a loose, hypocellular tissue, amorphous matrix. In 5 of 6 aneurysms, a thin layer of hypocellular tissue ran along the neck. Collagen and myofibroblasts were sparse in the dome. Swine aneurysms were filled with densely infiltrated tissue, including chronic inflammatory tissue and extensive, attenuated collagen fiber bundles associated with myofibroblasts. Thick layers of myofibroblasts entirely bridged the necks.
CONCLUSIONS: Absence of collagen deposition and scant myofibroblastic reaction to platinum coil embolization are seen in the rabbit model but not in swine aneurysms. The elastase-induced aneurysm model in rabbits is more suitable than sidewall swine aneurysms for testing of modified devices aimed at improving intra-aneurysmal fibrosis.
This article has been cited by other articles:
 |
|
 |
|
  R. Kadirvel, Y.H. Ding, D. Dai, D.A. Lewis, and D.F. Kallmes Intrinsic Pathway-Mediated Apoptosis in Elastase-Induced Aneurysms in Rabbits AJNR Am. J. Neuroradiol., January 1, 2010; 31(1): 165 - 169. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
C.T. Whitlow, C.P. Geer, C.W.T. Mattern, B.J. Mussat-Whitlow, S.K. Yazdani, J.L. Berry, J.H. Lalli, R.O. Claus, V.R. Challa, and P.P. Morris Endovascular Histologic Effects of Ultrathin Gold- or Vitronectin-Coated Platinum Aneurysm Coils in a Rodent Arterial Occlusion Model: A Preliminary Investigation AJNR Am. J. Neuroradiol., January 1, 2009; 30(1): 85 - 90. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
D.A. Lewis, Y.H. Ding, D. Dai, R. Kadirvel, M.A. Danielson, H.J. Cloft, and D.F. Kallmes Morbidity and Mortality Associated with Creation of Elastase-Induced Saccular Aneurysms in a Rabbit Model AJNR Am. J. Neuroradiol., January 1, 2009; 30(1): 91 - 94. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. Raymond, T. Darsaut, I. Salazkin, G. Gevry, and F. Bouzeghrane Mechanisms of Occlusion and Recanalization in Canine Carotid Bifurcation Aneurysms Embolized with Platinum Coils: An Alternative Concept AJNR Am. J. Neuroradiol., April 1, 2008; 29(4): 745 - 752. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 R. Kadirvel, Y.-H. Ding, D. Dai, D. A. Lewis, H. J. Cloft, and D. F. Kallmes Molecular Indices of Apoptosis Activation in Elastase-Induced Aneurysms After Embolization With Platinum Coils Stroke, October 1, 2007; 38(10): 2787 - 2794. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
D. Dai, Y.H. Ding, R. Kadirvel, D.A. Lewis, H.J. Cloft, and D.F. Kallmes Bone Formation in Elastase-Induced Rabbit Aneurysms Embolized with Platinum Coils: Report of 2 Cases AJNR Am. J. Neuroradiol., June 1, 2007; 28(6): 1176 - 1178. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
R. Kadirvel, D. Dai, Y.H. Ding, M.A. Danielson, D.A. Lewis, H.J. Cloft, and D.F. Kallmes Endovascular Treatment of Aneurysms: Healing Mechanisms in a Swine Model Are Associated with Increased Expression of Matrix Metalloproteinases, Vascular Cell Adhesion Molecule-1, and Vascular Endothelial Growth Factor, and Decreased Expression of Tissue Inhibitors of Matrix Metalloproteinases AJNR Am. J. Neuroradiol., May 1, 2007; 28(5): 849 - 856. [Abstract] [Full Text] [PDF]
|
|