title: Iodine based radiopacity of experimental blood clots for testing of mechanical thrombectomy devices.
abstract: BACKGROUND
  Barium sulfate powder used for radiopacity of experimental blood clots (EBCs) for testing mechanical thrombectomy devices (MTD) has negative effects on EBCs mechanical properties. In vitro and in vivo exploration was performed to determine if the iodine based contrast medium will have less negative effects on the EBCs than barium.
  
  
  METHODS
  Fresh blood from 2 swine was used to create fibrinogen enhanced and thrombin initiated EBC in tubes. Iodine radiopacity was achieved by mixing the blood with 65% Iohexol or by soaking the EBCs for 2 or 24 hours in Iohexol. The EBCs opacified with barium served as controls. In vitro study: The EBCs were subjected to four tests, manual elongation, catheter injection, radiopacity and contrast wash out tests. In vivo study: The common carotid arteries of 2 swine were embolized by either barium EBC or EBC soaked for 24 hours in Iohexol. The duration of radiopacity of the different EBCs was compared.
  
  
  RESULTS
  The EBCs opacified with Iohexol initially had higher radiopacity than the barium opacified EBCs. However, their opacity rapidly decreased with saline soaking and, particularly, after they were embolized in live animals. The mechanical properties of Iohexol opacified EBCs were inferior to barium opacified EBCs. The Iohexol mixed EBCs were less firm and elastic and half of them fragmented during catheter injection. The Iohexol soaked EBCs exhibited decreased tensile strength and elasticity compared to the barium EBCs.
  
  
  CONCLUSIONS
  Compared to barium, iodine based contrast medium does not offer any advantage for opacifying EBCs.
authors: Dotter Interventional Institute, Oregon Health & Science University, Portland, USA ; Department of Radiology, Xijing Hospital, Fourth Military Medical University, Xi'an, People's Republic of China.
authors: Zhong Hua
authors: ZH
authors: Luo
authors: Alex
authors: A
authors: Chung
authors: Gibok
authors: G
authors: Choi
authors: Yih Huie
authors: YH
authors: Lin
authors: Huajin
authors: H
authors: Pang
authors: Barry T
authors: BT
authors: Uchida
authors: Dusan
authors: D
authors: Pavcnik
authors: Miran
authors: M
authors: Jeromel
authors: Frederick S
authors: FS
authors: Keller
authors: Josef
authors: J
authors: Rösch
keywords: animal model; experimental radiology; preclinical interventional radiology; radioopaque experimental clot; stroke