Neuroform Stent-Assisted Coil Embolization of a Ruptured A1 Segment Anterior Cerebral Artery...
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Transcript of Neuroform Stent-Assisted Coil Embolization of a Ruptured A1 Segment Anterior Cerebral Artery...
Neurointerventional Report
Neuroform Stent-Assisted Coil
Embolization of a Ruptured A1
Segment Anterior Cerebral
Artery Aneurysm
Rishi Gupta, MD
Michael B. Horowitz, MD
Steven Gilman, MD
A B S T R A C T
We report a case of a 71-year-old woman who presented with
a ruptured wide-necked proximal anterior cerebral artery (ACA)
aneurysm that was successfully embolized using Neuroform
stent-assisted coiling.
Key words: Neuroform stent, aneurysm, anterior cerebral
artery.
Gupta R, Horowitz MB, Gilman S.
Neuroform stent-assisted coil embolization of a ruptured A1
segment anterior cerebral artery aneurysm.
J Neuroimaging 2006;16:117-119.
DOI: 10.1111/j.1552-6569.2006.00033.x
Introduction
Proximal A1 anterior cerebral artery (ACA) aneurysms
are responsible for less than 4% of cerebral aneurysms
and are associated with a multiplicity of aneurysms.1 They
represent a technical challenge for surgical clipping due
to the frequent adherence of basal perforating arteries to
Received June 6, 2005, and in revised form August 10,2005. Accepted for publication October 26, 2005.
From the Department of Neurology, Stroke Institute,University of Pittsburgh Medical Center, Pittsburgh, PA(RG); Department of Neurosurgery, University of Pitts-burgh Medical Center, Pittsburgh, PA (MH); Departmentof Neurosurgery, Erie Medical Center, Erie, Pennsylvania(SG).
Address correspondence to Michael B. Horowitz, MD,Department of Neurosurgery, University of PittsburghMedical Center, 200 Lothrop Street, Suite B-400, Pitts-burgh, PA 15213. E-mail: [email protected].
the aneurysm and thus carry a morbidity of 10-18% de-
pending on the case series.2,3 These aneurysms are often
fusiform and irregular, but can present with a wide neck
configuration.1
Endovascular treatment of wide-necked aneurysm
represents a technical challenge due to suboptimal
aneurysm occlusion and coil herniation into the parent
vessel. The use of balloon remodeling4 has allowed for
improved treatment of these aneurysms, but the recent
approval of the self-expanding Neuroform stent (Boston-
Scientific/Target Therapeutics, Fremont, CA) has yielded
an alternative method of treatment. There have been
several published reports and case series on the use of
stent-assisted coiling of the posterior circulation, carotid
artery, and middle cerebral artery aneurysms,5-8 but little
is known of utilizing this technique for the uncommon
proximal ACA aneurysm.
Case Report
A 71-year-old woman with a history of hypertension pre-
sented to our institution with a Hunt and Hess grade
IV/Fisher III subarachnoid hemorrhage. CT scan of
the head revealed early hydrocephalus with blood in
the interhemispheric fissure and basilar cistern. After
placement of an external ventricular drainage system,
the patient underwent cerebral angiography to deter-
mine the aneurysm’s location. The initial angiogram re-
vealed a wide-necked 7 × 10 mm left A1 segment ACA
aneurysm (Fig 1A). An injection from the right com-
mon carotid artery with cross-compression showed fill-
ing of both ACAs. Consideration was thus given to trap-
ping the aneurysm but there was concern for the loss of
the basal perforating branches and the recurrent artery
of Heubner from the A1 segment. Thus, stent-assisted
coiling was considered. After placement of a 6-French
Envoy guide catheter (Cordis, Miami Lakes, FL) in the
Copyright ◦C 2006 by the American Society of Neuroimaging 117
Fig 1. (A) A wide-necked proximal left A1 segment of the anterior cerebral artery aneurysm measuring 7 × 10 mm (white
arrow). (B) A 3.5 × 20 mm Neuroform stent (black arrowheads) was deployed across the neck of the aneurysm in the A1
segment in order to prevent coil herniation and loss of basal perforators. (C) A Prowler-14 microcatheter (white dashed arrow)
was navigated into the aneurysm through the interstices of the stent (black arrowheads). (D) A final angiographic run shows
preservation of the proximal anterior cerebral artery with complete occlusion of the aneurysm (black arrow).
left internal carotid artery (ICA), a Prowler-14 (Cordis,
Miami Lakes, FL) microcatheter and Transend (Boston
Scientific, Fremont, CA) microwire were gently navigated
across the neck of the aneurysm into the ipsilateral A2-A3
segment of the ACA. A 0.014-inch microwire (Transend
300 cm) was then exchanged through the microcatheter.
A 3.5 × 20 mm Neuroform self-expanding stent (Boston-
Scientific/Target Therapeutics, Fremont, CA) was de-
ployed across the neck of the aneurysm in the A1 segment
(Fig 1B).
The aneurysm was then catheterized through the in-
terstices of the stent using a Prowler-14 microcatheter
(Cordis, Miami Lakes, FL) and a Transcend (Boston-
Scientific/Target Therapeutics) 0.014-inch microwire
118 Journal of Neuroimaging Vol 16 No 2 April 2006
(Fig 1C). Coil embolization was performed using two
10-mm Micrus (Micrus Corp., Mountain View, CA) fram-
ing coils followed by sequential placement of GDC
(Boston-Scientific/Target Therapeutics, Fremont, CA)
coils to tightly pack the aneurysm. Post-embolization
angiography revealed a complete obliteration of the
aneurysm (Fig 1D). The patient was given a heparin bolus
of 30 units/kg when the guide catheter was placed in the
ICA with additional doses given to maintain an activated
clotting time between 250 and 300 seconds. A heparin
drip of 500 units/hour was maintained for 12 hours post-
procedure and then discontinued. The patient was also
given a clopidogrel load of 450 mg9 and aspirin, 325 mg,
immediately post-procedure. There were no technical or
neurological complications noted post-procedure.
Discussion
This case report demonstrates the feasibility of stent-
assisted coiling of a proximal ACA aneurysm. Surgical
clipping of such aneurysms can represent a challenge
as the perforators are often adherent to the aneurysm
making preservation of the A1 segment difficult.1 Given
the patient’s age and poor neurological grade, endovas-
cular therapy was considered as the primary therapeu-
tic modality for this patient. The Neuroform stent is the
only FDA-approved stent under the human device ex-
emption (HDE) protocol for use in treating wide-necked
aneurysms. Its flexibility and ease of navigation through
tortuous intracranial vessels allow for delivery to loca-
tions inaccessible to coronary stents. The ACA is par-
ticularly difficult due to its small luminal diameter and
acute angle of origin from the carotid terminus. As illus-
trated in this case, placement of the Neuroform stent is
feasible due to its flexibility and is potentially less trau-
matic due to its reduced radial force and self-expanding
nature.
Caution must be applied with this technology, as there
have been reports of stent migration when attempting to
catheterize the aneurysm through the interstices of the
stent.10 Additionally, the use of antiplatelet agents in the
setting of a ruptured cerebral aneurysm may pose poten-
tial for bleeding complications, as other procedures may
be required during acute hospitalization. There is also the
potential of stent thrombosis leading to thromboembolic
events,11 thus patients must be placed and maintained on
a dual antiplatelet regimen with clopidogrel and aspirin.
This report demonstrates that stent-assisted coiling of
a proximal ACA aneurysm is feasible and may be an
alternative therapy to the treatment of this uncommon
aneurysm.
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Gupta et al: Neuroform Stent-Assisted Coil Embolization 119