RT Journal Article
SR Electronic
T1 Mechanical Characterization of Thromboemboli in Acute Ischemic Stroke and Laboratory Embolus Analogs
JF American Journal of Neuroradiology
JO Am. J. Neuroradiol.
FD American Society of Neuroradiology
SP 1237
OP 1244
DO 10.3174/ajnr.A2485
VO 32
IS 7
A1 J.Y. Chueh
A1 A.K. Wakhloo
A1 G.H. Hendricks
A1 C.F. Silva
A1 J.P. Weaver
A1 M.J. Gounis
YR 2011
UL http://www.ajnr.org/content/32/7/1237.abstract
AB BACKGROUND AND PURPOSE: Mechanical behavior of the thromboembolus is one of the key factors that determine the efficacy of thrombectomy devices for revascularization in AIS. We characterized the mechanical properties and composition of thromboemboli from clinical cases and compared them with commonly used EAs. MATERIALS AND METHODS: Thromboemboli were obtained from patients with AIS by using aspiration devices and from carotid atherosclerotic plaques harvested during endarterectomy. In the laboratory, common EAs were created by varying blood donor species (human, porcine, and bovine), thrombin concentration, and presence of barium sulfate. Stiffness and elasticity of the specimens were measured with DMA. Scanning electron microscopy and histology were used to investigate the ultrastructure and composition of all specimens. RESULTS: Red thromboemboli from patients composed mainly of fibrin and erythrocytes were much softer than the calcified and cholesterol-rich material. Of the EAs created in the laboratory, those made from bovine blood presented the highest stiffness that was independent of thrombin concentration. Addition of thrombin increased the stiffness and elasticity of human and porcine EAs (P < .05). The presence of barium sulfate significantly reduced the elasticity of all EAs (P < .05). CONCLUSIONS: Endovascular device testing and development requires realistic EAs. The stiffness and elasticity of the cerebral thromboemboli analyzed in this study were closely matched by recalcified porcine EAs and thrombin-induced human EAs. Stiffness of the thrombus extracted from carotid endarterectomy specimens was similar with that of the thrombin-induced bovine and porcine EAs. ACDanticoagulant citrate dextroseAISacute ischemic strokeCEAcarotid endarterectomyDMAdynamic mechanical analyzerEintitial strain-end strainsecant modulus in a given strain range (initial strain to end strain)EAembolus analogEDSenergy dispersive x-ray spectroscopyH&Ehematoxylin-eosinICAinternal carotid arteryMCAmiddle cerebral arteryMSBMartius scarlet blueNIHUNational Institutes of Health unitS-Sstress-strainSEMscanning electron microscopy