title: Construction of 3 animal experimental models in the development of honeycomb microporous covered stents for the treatment of large wide-necked cerebral aneurysms.
abstract: The treatment of large or wide-necked cerebral aneurysms is extremely difficult, and carries a high risk of rupture, even when surgical or endovascular methods are available. We are developing novel honeycomb microporous covered stents for treating such aneurysms. In this study, 3 experimental animal models were designed and evaluated quantitatively before preclinical study. The stents were prepared using specially designed balloon-expandable stents (diameter 3.5-5.0 mm, length 16-28 mm) by dip-coating to completely cover their struts with polyurethane film (thickness 20 µm) and microprocessing to form the honeycomb pattern after expansion. (1) In an internal carotid artery canine model (n = 4), all stents mounted on the delivery catheter passed smoothly through the tortuous vessel with minimal arterial damage. (2) In an the large, wide-necked, outer-sidewall aneurysm canine model, almost all parts of the aneurysms had embolized immediately after stenting (n = 4), and histological examination at 2 months revealed neointimal formation with complete endothelialization at all stented segments and entirely organized aneurysms. (3) In a perforating artery rabbit model, all lumbar arteries remained patent (n = 3), with minimal change in the vascular flow pattern for over 1 year, even after placement of a second, overlapping stent (n = 3). At 2 months after stenting, the luminal surface was covered with complete thin neointimal formation. Excellent embolization performance of the honeycomb microporous covered stents without disturbing branching flow was confirmed at the aneurysms in this proof-of-concept study.
authors.affiliation: Division of Medical Engineering and Materials, National Cerebral and Cardiovascular Center Research Institute, 5-7-1 Fujishiro-dai, Suita, Osaka, 565-8565, Japan. ny@ncvc.go.jp.
authors.forename: Yasuhide
authors.initials: Y
authors.lastname: Nakayama
authors.affiliation: Department of Neurosurgery, National Cerebral and Cardiovascular Center, Suita, Osaka, Japan.
authors.forename: Tetsu
authors.initials: T
authors.lastname: Satow
authors.affiliation: Division of Medical Engineering and Materials, National Cerebral and Cardiovascular Center Research Institute, 5-7-1 Fujishiro-dai, Suita, Osaka, 565-8565, Japan.
authors.forename: Marina
authors.initials: M
authors.lastname: Funayama
authors.affiliation: Division of Medical Engineering and Materials, National Cerebral and Cardiovascular Center Research Institute, 5-7-1 Fujishiro-dai, Suita, Osaka, 565-8565, Japan.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Moriwaki
authors.affiliation: Department of Mechanical Engineering, Kansai University, Suita, Osaka, Japan.
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Tajikawa
authors.affiliation: Division of Medical Engineering and Materials, National Cerebral and Cardiovascular Center Research Institute, 5-7-1 Fujishiro-dai, Suita, Osaka, 565-8565, Japan.
authors.forename: Maya
authors.initials: M
authors.lastname: Furukoshi
authors.affiliation: Department of Neurosurgery, National Cerebral and Cardiovascular Center, Suita, Osaka, Japan.
authors.forename: Eika
authors.initials: E
authors.lastname: Hamano
authors.affiliation: Department of Neurosurgery, National Cerebral and Cardiovascular Center, Suita, Osaka, Japan.
authors.forename: Daizo
authors.initials: D
authors.lastname: Ishi
authors.affiliation: Department of Neurosurgery, National Cerebral and Cardiovascular Center, Suita, Osaka, Japan.
authors.forename: Masataka
authors.initials: M
authors.lastname: Hayashi
authors.affiliation: Department of Neurosurgery, National Cerebral and Cardiovascular Center, Suita, Osaka, Japan.
authors.forename: Sei
authors.initials: S
authors.lastname: Sugata
authors.affiliation: Department of Pathology, National Cerebral and Cardiovascular Center, Suita, Osaka, Japan.
authors.forename: Hatsue
authors.initials: H
authors.lastname: Ishibashi-Ueda
authors.affiliation: Department of Neurosurgery, National Cerebral and Cardiovascular Center, Suita, Osaka, Japan.
authors.forename: Jun C
authors.initials: JC
authors.lastname: Takahashi
mesh_terms: D000368:Aged; D000818:Animals; D001012:Aorta, Abdominal; D017536:Carotid Artery, Common; D004195:Disease Models, Animal; D004285:Dogs; D004621:Embolization, Therapeutic; D057510:Endovascular Procedures / Q000295:instrumentation*; D006801:Humans; D002532:Intracranial Aneurysm / Q000628:therapy*; D008297:Male; D011140:Polyurethanes; D011817:Rabbits; D015607:Stents; D014654:Vascular Patency
chemical_list: D011140:Polyurethanes
keywords: Cerebral aneurysms; Covered stents; Embolization; Microporous membrane