Journal of Artificial Organs

, Volume 19, Issue 2, pp 179–187 | Cite as

Construction of 3 animal experimental models in the development of honeycomb microporous covered stents for the treatment of large wide-necked cerebral aneurysms

  • Yasuhide Nakayama
  • Tetsu Satow
  • Marina Funayama
  • Takeshi Moriwaki
  • Tsutomu Tajikawa
  • Maya Furukoshi
  • Eika Hamano
  • Daizo Ishi
  • Masataka Hayashi
  • Sei Sugata
  • Hatsue Ishibashi-Ueda
  • Jun C. Takahashi
Original Article Others

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.

Keywords

Covered stents Cerebral aneurysms Embolization Microporous membrane 

Notes

Acknowledgments

This work was performed as a Medical Device Innovation Circumstances Improvement (Medici) project, and was supported by grants from the Ministry of Health, Labor, and Welfare of Japan. Three experimental animal models were designed based on advices from Japan’s Pharmaceuticals and Medical Devices Agency (PMDA).

Compliance with ethical standards

Conflict of interest

None.

References

  1. 1.
    Fiorella D, Woo HH, Albuquerque FC, Nelson PK. Definitive reconstruction of circumferential fusiform intracranial aneurysms with the pipeline embolization device. Neurosurgery. 2008;62:1115–21.CrossRefPubMedGoogle Scholar
  2. 2.
    Lylyk P, Miranda C, Ceratto R, Ferrario A, Scrivano E, Luna HR, Berez AL, Tran Q, Nelson PK, Fiorella D. Curative endovascular reconstruction of cerebral aneurysms with the pipeline embolization device: the Buenos Aires experience. Neurosurgery. 2009;64:632–42.CrossRefPubMedGoogle Scholar
  3. 3.
    Saatci I, Yavuz K, Ozer C, Geyil S, Cekirge HS. Treatment of intracranial aneurysms using the Pipeline flow diverter embolization device: a single-center experience with long-term follow-up results. AJNR Am J Neuroradiol. 2012;33:1436–46.CrossRefPubMedGoogle Scholar
  4. 4.
    Nihi S, Nakayama Y, Ishibashi-Ueda H, Okamoto Y, Yoshida M. Development of microporous self-expanding stent grafts for treating cerebral aneurysms: designing micropores to control intimal hyperplasia. J Artif Organs. 2011;14:348–56.CrossRefGoogle Scholar
  5. 5.
    Nishi S, Nakayama Y, Ishibashi-Ueda H, Yoshida M, Yonetani H. Treatment of rabbit carotid aneurysms by hybrid stents (microporous thin polyurethane-covered stents): preservation of side-branches. Biomater Appl. 2014;28:1097–104.CrossRefGoogle Scholar
  6. 6.
    Bonneville F, Sourour N, Biondi A. Intracranial aneurysms: an overview. Neuroimaging Clin N Am. 2006;16:371–82.CrossRefPubMedGoogle Scholar
  7. 7.
    Li J, Lan ZG, Liu Y, He M, You C. Large and giant ventral paraclinoid carotid aneurysms; surgical techniques, complications and outcomes. Clin Neurol Neurosurg. 2012;114:907–13.CrossRefPubMedGoogle Scholar
  8. 8.
    Ross IB, Weil A, Piotin M, Moret J. Endovascular treatment of distally located giant aneurysms. Neurosurgery. 2002;47:1147–52.CrossRefGoogle Scholar
  9. 9.
    Standhardt H, Boecher-Schwarz H, Gruber A, Benesch T, Knosp E, Bavinzski G. Endovascular treatment of unruptured intracranial aneurysms with Guglielmi detachable coils: short- and long-term results of a single-centre series. Stroke. 2008;39:899–904.CrossRefPubMedGoogle Scholar
  10. 10.
    Gruber A, Killer M, Bavinzski G, Richling B. Clinical and angiographic results of endosaccular coiling treatment of giant and very large intracranial aneurysms: a 7-year, single-center experience. Neurosurgery. 1999;45:793–800.CrossRefPubMedGoogle Scholar
  11. 11.
    Zhu YQ, Li MH, Xie J, Tan HQ, Cheng YS, Wang JB. Treatment of carotid siphon aneurysms by use of the Willis stent graft: an angiographic and histopathological study. Eur Radiol. 2010;20:1974–84.CrossRefPubMedGoogle Scholar
  12. 12.
    Tajikawa T, Nakagawa Y, Kurebayashi Y, Nishi S, Nakayama Y. Development of microporous covered stent for cerebral aneurysm treatment. Trans JSME Ser. 2013;79:2013–5.CrossRefGoogle Scholar
  13. 13.
    Nishi S, Nakayama Y, Ishibashi-Ueda H, Masato Y. Occlusion of canine aneurysms using microporous self-expanding stent grafts: long-term follow-up. Clin Neurol Neurosurg. 2014;122:34–41.CrossRefPubMedGoogle Scholar
  14. 14.
    Masuo O, Terada T, Walker G, Tsuura M, Matsumoto H, Tohya K, Kimura M, Nakai K, Itakura T. Study of the patency of small arterial branches after stent placement with an experimental in vivo medel. AJNR Am J Neuroradiol. 2002;23:706–10.PubMedGoogle Scholar

Copyright information

© The Japanese Society for Artificial Organs 2016

Authors and Affiliations

  • Yasuhide Nakayama
    • 1
  • Tetsu Satow
    • 2
  • Marina Funayama
    • 1
  • Takeshi Moriwaki
    • 1
  • Tsutomu Tajikawa
    • 3
  • Maya Furukoshi
    • 1
  • Eika Hamano
    • 2
  • Daizo Ishi
    • 2
  • Masataka Hayashi
    • 2
  • Sei Sugata
    • 2
  • Hatsue Ishibashi-Ueda
    • 4
  • Jun C. Takahashi
    • 2
  1. 1.Division of Medical Engineering and MaterialsNational Cerebral and Cardiovascular Center Research InstituteSuitaJapan
  2. 2.Department of NeurosurgeryNational Cerebral and Cardiovascular CenterSuitaJapan
  3. 3.Department of Mechanical EngineeringKansai UniversitySuitaJapan
  4. 4.Department of PathologyNational Cerebral and Cardiovascular CenterSuitaJapan

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