High‐Resolution Imaging of Interaction Between Thrombus and Stent‐Retriever in Patients With Acute Ischemic Stroke
Authors: Autar Anouchska S. A. , Hund Hajo M. , Ramlal Sharad A. , Hansen Daniël , Lycklama à Nijeholt Geert J. , Emmer Bart J. , de Maat Moniek P. M. , Dippel Diederik W. J. , van der Lugt Aad , van Es Adriaan C. G. M. , van Beusekom Heleen M. M. ,   on behalf of the MR CLEAN Registry Investigators, Jansen Ivo G.H. , Mulder Maxim J.H.L. , Goldhoorn Robert‐Jan B. , Emmer Bart J. , van Es Adriaan C.G.M. , Roozenbeek Bob , Schonewille Wouter J. , van den Berg René , Coutinho Jonathan M. , Staals Julie , Postma Alida A. , Lycklama à Nijeholt Geert J. , Hofmeijer Jeannette , Martens Jasper M. , den Hertog Heleen M. , Sturm Emiel J.C. , van der Worp H. Bart , Lo Rob H. , Heijboer Roel J.J. , Keizer Koos , Uyttenboogaart Maarten , Eshghi Omid , Wermer Marieke J.H. , van Walderveen Marianne A.A. , van Dijk Ewoud J. , Boogaarts Hieronymus D. , de Bruijn Sebastiaan F. , van Dijk Lukas C. , van den Berg Jan S.P. , van Hasselt Boudewijn A.A.M. , de Kort Paul L.M. , Peluso Jo P.P. , Schreuder Tobien H.C.M.L. , Aerden Leo A.M. , Dallinga René J. , Sprengers Marieke E.S. , Yo Lonneke S.F. , Jenniskens Sjoerd F.M. , Roosendaal Stefan D. , van der Kallen Bas F.W. , van den Wijngaard Ido R. , Bot Joost C.J. , van Doormaal Pieter J. , Flach H. Zwenneke , Venema Esmee , Lingsma Hester F. , Beenen Ludo F.M. , Yoo Albert J. , Boiten Jelis , Vos Jan A. , Roos Yvo B.W.E.M. , van Oostenbrugge Robert J. , van der Lugt Aad , van Zwam Wim H. , Dippel Diederik W.J. , Majoie Charles B.L.M. 
Published: June 2018

Background

Currently, acute ischemic stroke is still a leading cause of mortality and morbidity. Approximately 2 years ago, mechanical thrombectomy was proven beneficial as a revolutionary new therapy for stroke in the
MR
‐CLEAN trial (A Multicenter Randomized Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands). However, the mechanisms by which the thrombectomy device, or stent‐retriever, interacts with the thrombus are largely unknown. A better understanding could lead to improved efficacy of mechanical thrombectomy devices.

Methods and Results
Seven stent‐retrievers with thrombi still entrapped were collected directly after thrombectomy. The stent‐retrievers were studied using micro computed tomography, followed by scanning electron microscopy and light microscopy. Two independent observers rated interaction type and thrombus surface structure (porous filamentous or dense) at the interaction sites.

A total of 79 interaction sites between thrombus and stent‐retriever were categorized. Thrombus‐stent‐retriever interaction was found to be adhesive (n=44; 56%) or mechanical (n=35; 44%). Adhesive interaction was most frequently observed at interaction sites with a dense surface, compared with interaction sites with a porous filamentous fibrin surface (38/58; 66% versus 6/21; 29%,
P
=0.011).

Conclusions
The interaction between thrombus and stent‐retriever was predominantly adhesive, not mechanical. Adhesive interaction was strongly associated with the presence of a dense thrombus surface without a porous filamentous fibrin network.