Experimental Polyvinyl Alcohol Core Coil for a Drug Delivery System

Abstract

We developed a new type of coil with a polyvinyl alcohol core (PVA-core coil) to absorb and release various types of biologically active materials, for the endovascular treatment of intracranial aneurysms. A 10 mm segment of the PVA-core coil was used in this study. PVA-core coils were immersed in basic fibroblast growth factor (b-FGF) solution. The PVA-core coil, which absorbed b-FGF in the PVA core, was named FGF-core coil. This coil gradually released b-FGF in the solution without b-FGF. In vitro study, FGF-core coils, PVA-core coils and unmodified coils were cultured with fibroblasts (NIH3T3) respectively and their surface was observed with scanning electron microscopy (SEM). In vivo study, each coils were inserted into the rat common carotid artery. Rats were sacrificed and the arterial lumen were histologically examined 14 days and 28 days after coil implantation. Electron microscopy findings demonstrated remarkable cellular adhesion to the surface of the FGF-core coils, while no adhesion to the surface of the PVA-core coils and unmodified coils was found. Histologically, remarkable cellular proliferation and wall thickness like neointimal hyperplasia was demonstrated in the implanted common carotid artery of the FGF-core coil group at 14 days and 28 days. On the other hand, these changes did not occur in PVA-core coil group and unmodified coil group. We suggest that FGF-core coils may be effective to induce fibrotic changes inside cerebral aneurysms.

Keywords

polyvinyl alcohol b-FGF drug delivery fibrosis

Get full access to this article

View all access options for this article.

References

Bavinzski

Talazoglu

: Gross and microscopic histopathological findings in aneurysms of the human brain treated with Guglielmi detachable coils. J Neurosurg 91: 284–293, 1999.

Abrahams

Diamond

: Topic review: surface modifications enhancing biological activity of Guglielmi detachable coils in treating intracranial aneurysms. Surg Neurol 54: 34–41, 2000.

Kallmes

Borland

: In vitro proliferation and adhesion of basic fibroblast growth factor-producing fibroblast on platinum coils. Radiology 206: 237–243, 1998.

Kallmes

Williams

: Platinum coil-mediated implantation of growth factor-secreting endovascular tissue grafts: an in vivo study. Radiology 207: 519–523, 1998.

Tamatani

Ozawa

: Histological interaction of cultured endothelial cells and endovascular embolic materials coated with exracellular matrix. J Neurosurg 86: 109–112, 1997.

Abrahams

Forman

: Delivery of human vascular endothelial growth factor with platinum coils enhances wall thickness and coil impregnation in rat aneurysmal model. Am J Neuroradiol 22: 1410–1417, 2001.

Marx

Cloft

: Endovascular treatment of experimental aneurysms by use of biologically modified embolic devices: coil-mediated intraaneurysmal delivery of fibroblast tissure allografts. Am J Neuroradiol 22: 323–333, 2001.

Gast

Altes

: Transforming growth factor β-coated platinum coils for endovascular treatment of aneurysms: an animal study. Neurosurgery 49: 690–769, 2001.

Murayama

Vineuela

: Ion implantation and protein coating of detachable coils for endovascular treatment of cerebral aneurysms: concepts and preliminary results in swine models. Neurosurgery 40: 1233–1244, 1997.

10.

Murayama

Suzuki

: Development of a biologically active Guglielmi detachable coil for the treatment of cerebral aneurysms. Part 1: in vitro study. Am J Neuroradiol 20: 1986–1991, 1999.

11.

Murayama

Vineuela

: Development of a biologically active Guglielmi detachable coil for the treatment of cerebral aneurysms. Part 2: an experimental study in a swine models. Am J Neuroradiol 20: 1992–1999, 1999.

12.

Dawson

Shengelaia

: Histologic effects of collagen-filled interlocking detachable coils in the ablation of experimental aneurysms in swine. Am J Neuroradiol 17: 853–858, 1996.

13.

Abrahams

Forman

: Biogredable polyglycolide endovascular coils promote wall thickness and drug delivery in a rat aneurysmal model. Neurosurgery 49: 1187–1195, 2001.

14.

Murayama

Vinuera

: Bioabsorbable polymeric material coils for embolization of intracranial aneurysms; a preliminary experimental study. J Neurosurg 94: 454–463, 2001.

15.

Buruczak

Gamian

: Long-term in vivo performance and biocompatibility of polyvinyl alcohol hydrogel macrocapsules for hybrid type artificial pancrreas. Biomaterials 17: 2351–2356, 1996.

16.

Chuang

Young

: Properties of the polyvinyl alcohol/chitosan blend and its effect on the culture of fibroblast in vitro. Biomaterials 20: 1479–1487, 1999.

17.

Sano

Tokoro

: A new drug delivery system utilizing piggyback contact lenses. Acta Ophthalmol Scand 74: 243–248, 1996.