title: Evaluation of occurring complications after flow diverter treatment of elastase-induced aneurysm in rabbits using micro-CT and MRI at 9.4 T.
abstract: BACKGROUND
  Flow diverters are increasingly being used to treat intracranial aneurysms. This study evaluates occurring complications of flow-diverting devices in the treatment of experimental aneurysms, involving the use of micro-CT and small animal MRI at 9.4 T, in correlation to angiographic and histological findings.
  
  
  METHODS
  We previously published two preclinical studies, in which we assessed two different flow diverters in the treatment of elastase-induced aneurysms. Devices have been implanted across the aneurysm neck as well as in the abdominal aorta. From these studies, a total of 65 devices (prototype FD (n = 30) and Derivo embolization device (n = 35)) additionally underwent micro-CT and MRI after angiographic follow-up and before being histologically examined.
  
  
  RESULTS
  The different architectures of both devices were precisely comparable due to high-resolution micro-CT imaging. Micro-CT revealed wire fractures in nine cases (30 %) only with the prototype FD. In three cases (10 %), severe wire fractures correlated with an in-stent stenosis due to intimal hyperplasia. Other complications, like distal stent occlusions and post-stent stenosis, were seen in both groups and verified with both imaging techniques. Osseous metaplasia were correlated to calcifications seen with micro-CT. MRI enabled visualization of the position of the implanted devices relative to the aneurysm and revealed incomplete aneurysm neck coverage with the prototype FD in two cases (6.7 %).
  
  
  CONCLUSIONS
  Micro-CT and 9.4-T MRI are valid to discover and understand occurring complications of flow diverters in the preclinical phase and can serve as evaluation tools to minimize complication rates of endovascular devices in the future.
authors.affiliation: Department of Neuroradiology, Saarland University Hospital, Kirrbergerstraße1, 66424, Homburg, Saar, Germany. andreassimgen@googlemail.com.
authors.forename: Andreas
authors.identifier: http://orcid.org/0000-0003-0913-6740
authors.initials: A
authors.lastname: Simgen
authors.affiliation: Department of Neuroradiology, Saarland University Hospital, Kirrbergerstraße1, 66424, Homburg, Saar, Germany.
authors.forename: Désirée
authors.initials: D
authors.lastname: Ley
authors.affiliation: Department of Neuroradiology, Clinic Bremen-Mitte, Bremen, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Roth
authors.affiliation: Acandis GmbH, Pforzheim, Germany.
authors.forename: Giorgio Franco Maria
authors.initials: GF
authors.lastname: Cattaneo
authors.affiliation: Department of Neuroradiology, Saarland University Hospital, Kirrbergerstraße1, 66424, Homburg, Saar, Germany.
authors.forename: Ruben
authors.initials: R
authors.lastname: Mühl-Benninghaus
authors.affiliation: Department of Experimental Surgery, Saarland University Hospital, Homburg, Saar, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Müller
authors.affiliation: Department of Neuroradiology, Saarland University Hospital, Kirrbergerstraße1, 66424, Homburg, Saar, Germany.
authors.forename: Heiko
authors.initials: H
authors.lastname: Körner
authors.affiliation: Department of Pathology, Saarland University Hospital, Homburg, Saar, Germany.
authors.forename: Yoo-Jin
authors.initials: YJ
authors.lastname: Kim
authors.affiliation: Department of Cardiology, Saarland University Hospital, Homburg, Saar, Germany.
authors.forename: Bruno
authors.initials: B
authors.lastname: Scheller
authors.affiliation: Department of Neuroradiology, Saarland University Hospital, Kirrbergerstraße1, 66424, Homburg, Saar, Germany.
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Reith
authors.affiliation: Department of Neuroradiology, Saarland University Hospital, Kirrbergerstraße1, 66424, Homburg, Saar, Germany.
authors.forename: Umut
authors.initials: U
authors.lastname: Yilmaz
mesh_terms: D000818:Animals; D002533:Cerebral Angiography / Q000379:methods; D002548:Cerebral Revascularization / Q000009:adverse effects* / Q000295:instrumentation* / Q000379:methods; D000072226:Computed Tomography Angiography / Q000379:methods; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005260:Female; D006083:Graft Occlusion, Vascular / Q000000981:diagnostic imaging / Q000209:etiology*; D002532:Intracranial Aneurysm / Q000139:chemically induced / Q000000981:diagnostic imaging* / Q000628:therapy*; D018810:Magnetic Resonance Angiography / Q000379:methods*; D010196:Pancreatic Elastase; D011817:Rabbits; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D016896:Treatment Outcome; D055114:X-Ray Microtomography / Q000379:methods*
chemical_list: D010196:Pancreatic Elastase
keywords: 9.4-T MRI; Aneurysm; Animal studies; Flow diverter; Micro-CT