Endovascular Coil Occlusion of Intracranial Aneurysms Assisted by a Novel Self-Expandable Nitinol Microstent (Neuroform)

Abstract

Endovascular treatment of wide neck intracranial aneurysms is technically difficult and leads to less favorable treatment results and long term outcome. We participated in a multicenter prospective study to evaluate the safety and performance of a new self-expandable nitinol micro stent (Neuroform) in stent assisted coil occlusion of wide neck intracranial aneurysms. Eighteen patients were enrolled in the study in a single center. The anatomy of the target aneurysm and the parent vessel, technical details of the procedure, device functionality, anatomic and clinical results were evaluated. All enrolled aneurysms were either wide necked or showed an unfavorable neck-to-fundus ratio. In 16 out of 18 patients the Neuroform device allowed stent assisted coil occlusion of the aneurysm. The occlusion rate was 95% in eight patients and 100% in eight patients. The two failures were both due to anatomic reasons. Flexibility of the stent, behavior during deployment and subsequent ability to retain coils within the aneurysmal sac were considered as good as or better than the properties of previous balloon expandable stents. No device-related adverse events were encountered. Procedure-related clinical complications occurred in seven patients but caused no severe permanent neurological deficit. The Neuroform neurovascular stenting system is a safe and effective adjunct for the stent-assisted coil occlusion of wide necked intracranial aneurysms. The major advantages of this device are its self-expanding property and very high flexibility which allows safe navigation, easy sizing, as well as accurate positioning of the stent while providing sufficient bridging of the aneurysm neck for subsequent coil placement.

Keywords

intracranial aneurysm electrolytically detachable coil intracranial stent nitinol embolization internal carotid artery vertebral artery basilar artery

Get full access to this article

View all access options for this article.

References

Lot

Houdart

: Combined management of intracranial aneurysms by surgical and endovascular treatment. Modalities and results from a series of 395 cases. Acta Neurochir 141: 557–562, 1999.

Vinuela

Duckwiler

: Guglielmi detachable coil embolization of acute intracranial aneurysm: perioperative anatomical and clinical outcome in 403 patients. J Neurosurg 86: 475–482, 1997.

Assali

Sdringola

: Endovascular repair of traumatic pseudoaneurysm by uncovered self-expandable stenting with or without transstent coiling of the aneurysm cavity. Cathet Cardiovasc Intervent 53: 253–258, 2001.

Bai

Masuda

: Neointima formation after vascular stent implantation. Spatial and chronological distribution of smooth muscle cell proliferation and phenotypic modulation. Arterioscler Throm 14: 1846–1853, 1994.

Cloft

Joseph

: Use of three-dimensional Guglielmi detachable coils in the treatment of wide-necked cerebral aneurysms. Am J Neuroradiol 21: 1312–1314, 2000.

Fessler

Ringer

: Intracranial stent placement to trap an extruded coil during endovascular aneurysm treatment: technical note. Neurosurgery 46: 248–253, 2000.

Geremia

Haklin

: Embolization of experimentally created aneurysms with intravascular stent devices. Am J Neuroradiol 15: 1223–1231, 1994.

Gomez

Misra

: Elective stenting of symptomatic basilar artery stenosis. Stroke 31: 95–99, 2000.

Hayakawa

Murayama

: Natural history of the neck remnant of a cerebral aneurysm treated with the Guglielmi detachable coil system. J Neurosurg 93: 561–568, 2000.

10.

Higashida

Smith

: Intravascular stent and endovascular coil placement for a ruptured fusiform aneurysm of the basilar artery. Case report and review of the literature. J Neurosurg 87: 944–949, 1997.

11.

Horowitz

Levy

: Transluminal stent-assisted coil embolization of a vertebral confluence aneurysm. Surg Neurol 55: 291–296, 2001.

12.

Lanzino

Fessler

: Angioplasty and stenting of basilar artery stenosis: technical case report. Neurosurgery 45: 404–407, 1999.

13.

Lanzino

Wakhloo

: Efficacy and current limitations of intravascular stents for intracranial internal carotid, vertebral, and basilar artery aneurysms. J Neurosurg 91: 538–546, 1999.

14.

Lavine

Larsen

: Parent vessel Guglielmi detachable coil herniation during wide-necked aneurysm embolization: treatment with intracranial stent placement. Two technical case reports. Neurosurgery 46: 1013–1017, 2000.

15.

Lempert

Malek

: Endovascular treatment of ruptured posterior circulation cerebral aneurysm: clinical and angiographic outcomes. Stroke 31: 100–110, 2000.

16.

Lownie

Pelz

: Endovascular treatment of a large vertebral artery aneurysm using stent and coils. Can J Neurol Sci 27: 162–165, 2000.

17.

Lylyk

Ceratto

: Treatment of vertebral dissecting aneurysm with stents and coils: technical case report. Neurosurgery 43: 385–388, 1998.

18.

Lylyk

Cohen

: Combined endovascular treatment of dissecting vertebral artery aneurysms by using stents and coils. J Neurosurg 94: 427–432, 2001.

19.

Malek

Higashida

: Tandem intracranial stent deployment for treatment of an iatrogenic, flow-limiting, basilar artery dissection: technical case report. Neurosurgery 45: 919–924, 1999.

20.

Massoud

Turjman

: Endovascular treatment of fusiform aneurysms with stents and coils: technical feasibility in a swine model. Am J Neuroradiol 16: 1953–1963, 1995.

21.

Mericle

Lanzino

: Stenting and secondary coiling of intracranial internal carotid artery aneurysm: technical case report. Neurosurgery 43: 1229–1233, 1998.

22.

Miyachi

Ishiguchi

: Endovascular stenting of a traumatic dissecting aneurysm of the extracranial internal carotid artery - case report. Neurol Med Chir 37: 270–274, 1997.

23.

Moret

Cognard

: Reconstruction technique in the treatment of wide-neck intracranial aneurysms: long-term angiographic and clinical results - Apropos of 56 cases. J Neuroradiol 24: 30–44, 1997.

24.

Murayama

Vinuela

: Endovascular treatment of experimental aneurysms by use of a combination of liquid embolic agents and protective devices. Am J Neuroradiol 21: 1726–1735, 2000.

25.

Redekop

Marotta

: Treatment of traumatic aneurysms and arteriovenous fistulas of the skull base by using endovascular stents. J Neurosurg 95: 412–419, 2001.

26.

Sekhon

LHS

Morgan

: Combined endovascular stent implantation and endosaccular coil placement for the treatment of a wide-necked vertebral artery aneurysm: technical case report. Neurosurgery 43: 380–384, 1998.

27.

Storey

Marks

: Vertebral artery stenting following percutaneous transluminal angioplasty. J Neurosurg 84: 883–887, 1996.

28.

Szikora

Guterman

: Endovascular treatment of experimental aneurysms with liquid polymers. The protective potential of stents. Neurosurgery 38: 339–347, 1996.

29.

Szikora

Guterman

: Combined use of stents and coils to treat experimental wide-necked carotid aneurysms: preliminary results. Am J Neuroradiol 15: 1091–1102, 1994.

30.

Turjman

Massoud

: Combined stent implantation and endosaccular coil placement for treatment of experimental wide-necked aneurysms: a feasibility study in swine. Am J Neuroradiol 15: 1087–1090, 1994.

31.

Turk

Rappe

: Evaluation of the TriSpan neck bridge device for the treatment of wide-necked aneurysms. An experimental study in canines. Stroke 32: 492–497, 2001.

32.

Wakhloo

Lanzino

: Stents for intracranial aneurysms: the beginning of a new endovascular era? Nerosurgery 43: 377–379, 1998.

33.

Wakhloo

Schellhammer

: Self-expanding and balloon expandable stents in the treatment of carotid aneurysms: an experimental study in the canine model. Am J Neuroradiol 15: 493–502, 1994.

34.

Weber

Henkes

: Stentimplantation in die A. basilaris zur Unterstützung der endovaskulären Aneurysmabehandlung. Nervenarzt 71: 843–848, 2000.

35.

Weber

Henkes

: Wirksamkeit and Sicherheit der Implantation ballon-expandierbarer Stents in intrakranielle Gefäße. Klin Neuroradiol 11: 157, 2001.

36.

Zubillaga

Guglielmi

: Endovascular occlusion of intracranial aneurysms with electrically detachable coils: correlation of aneurysm neck size and treatment results. Am J Neuroradiol 15: 815–820, 1994.