Comparison of platinum and first-generation Matrix coils in under-packed canine side-wall aneurysms: evaluation of progressive thrombosis.
BACKGROUND
There is much speculation in reference to the occurrence and mechanisms of progressive aneurysm occlusion after treatment with bioactive coils. However, to our knowledge, there are no studies documenting the impact on progressive occlusion in aneurysms that are intentionally under-packed.


METHODS
A total of 24 experimental side-wall aneurysms were created in canine common carotid arteries. Of these 24, 9 were treated with Guglielmi detachable coils (GDC) and 15 with first-generation Matrix (Matrix1) coils to packing densities of 22% or less. Angiograms were obtained immediately after treatment and again at the time of explant at 2 weeks, 8 weeks, or 12 weeks, and were graded utilizing the Raymond scale. At the time of the final angiography and explant all aneurysms were histologically processed and evaluated.


RESULTS
At the conclusion of initial coiling, near or complete occlusion was achieved in 7 of the 15 aneurysms (47%) treated with Matrix1 coils and in 2 of the 9 (22%) treated with GDC. Of the aneurysms that were incompletely occluded, six of eight (75%) treated with Matrix1 coils and two of seven (29%) treated with GDC showed progressive thrombosis at explant. Histopathological analysis demonstrated that the aneurysms treated with Matrix1 coils had increased fibrocellular tissue and inflammation, with less histological recanalization or vascular spaces, relative to those treated with GDC.


CONCLUSIONS
Experimental wide-necked side-wall canine aneurysms suboptimally treated with first-generation Matrix1 coils had a higher incidence of progressive occlusion and on histological analysis showed evidence of more advanced thrombus organization than did those treated with GDC.
Turk
Aquilla S
AS
Department of Radiology, University of Wisconsin Hospital and Clinics, 600 Highland Ave., Madison, WI, 53792, USA. aturk@uwhealth.org
Luty
Christopher M
CM
Grum
Katherine
K
Grinde
Julie
J
Consigny
Dan
D
Pulfer
Kari
K
Rappe
Al
A
Strother
Charles M
CM
D000783:Aneurysm / Q000000981:diagnostic imaging / Q000473:pathology / Q000628:therapy*; D000818:Animals; D017536:Carotid Artery, Common; D020099:Coated Materials, Biocompatible; D004195:Disease Models, Animal; D004285:Dogs; D004621:Embolization, Therapeutic / Q000295:instrumentation*; D004867:Equipment Design; D010984:Platinum; D011859:Radiography; D013927:Thrombosis / Q000000981:diagnostic imaging / Q000209:etiology* / Q000473:pathology
D020099:Coated Materials, Biocompatible; D010984:Platinum
Stroke. 2005 Oct;36(10):2176-80
16151028
J Neurosurg. 1999 Aug;91(2):284-93
10433317
AJNR Am J Neuroradiol. 2007 Mar;28(3):531-2
17353330
AJNR Am J Neuroradiol. 1992 Jul-Aug;13(4):1089-95
1636518
Neurosurgery. 1995 Jan;36(1):133-9; discussion 139-40
7708149
AJNR Am J Neuroradiol. 2005 Sep;26(8):1932-6
16155137
AJNR Am J Neuroradiol. 1994 May;15(5):815-20
8059647
J Neuroradiol. 1999 Jun;26(2):92-100
10444933
Stroke. 2003 Aug;34(8):2031-7
12869719
AJNR Am J Neuroradiol. 1993 Jul-Aug;14(4):794-8
8352145
Stroke. 2004 Jun;35(6):1471-5
15105520
AJNR Am J Neuroradiol. 1997 Apr;18(4):667-72
9127027
N Engl J Med. 1954 Jan 21;250(3):104-6
13119853
Neurosurgery. 1997 Jun;40(6):1233-43; discussion 1243-4
9179897
Radiology. 1999 Oct;213(1):217-22
10540665
J Neurosurg. 2006 Aug;105(2):192-9
17219822
AJNR Am J Neuroradiol. 1990 Mar-Apr;11(2):249-52
2107707
J Neurosurg. 1997 Feb;86(2):211-9
9010422
AJNR Am J Neuroradiol. 1999 Nov-Dec;20(10):1992-9
10588133
AJNR Am J Neuroradiol. 2006 Feb;27(2):283-8
16484393
Stroke. 2005 Sep;36(9):1948-53
16051893
Radiology. 1998 May;207(2):519-23
9577504
Stroke. 2003 Jun;34(6):1398-403
12775880
J Neurosurg. 1997 Mar;86(3):475-82
9046305
Neurosurgery. 2006 Jan;58(1):51-9; discussion 51-9
16385329
AJNR Am J Neuroradiol. 1999 Aug;20(7):1301-8
10472990
J Neurosurg. 1997 Aug;87(2):176-83
9254079