Saccular Intracranial Aneurysm Coiling: Experience in

19 Pages·2008·0.38 MB·English

Hany Zakieldine
Saccular Intracranial Aneurysm Coiling: Experience in
Department of Neurology, Ain-Shams University

Hany Zakieldine
Department of Neurology, Ain Shams University

ABSTRACT

Background: Subarachnoid hemorrhage is a devastating type of stroke associated with 45% case fatality
and 30% long-term dependency in survivors. Ruptured aneurysms should be treated early (within 24 to 72 hours)
because the risk of subsequent rupture is high. Options for treatment include surgical clipping and endovascular
coilings which is less invasive. Endovascular coiling has been proven to be effective and safer than clipping in
most ruptured and unruptured intracranial aneurysms. Methods: We performed endovascular coiling for ruptured
saccular aneurysm (presenting with acute subarachnoid hemorrhage, Hunt and Hess grade I-IV) and for
asymptomatic aneurysms (≥7 mm in the anterior circulation or ≤ 7 mm in the posterior circulation in patients <
60 y old or with personal or family history of subarachnoid hemorrhage). All patients underwent clinical
assessment together with Hunt and Hess scale (H&H scale) and modified Rankin Scale (mRS) upon discharge.
Patients also performed CT scan brain +/- CSF analysis. Then six vessels digital subtraction cerebral
angiography (DSA) was done followed by endovascular coiling of the aneurysm. Follow up by mRS and MRA
brain or DSA was done after 6 months and then yearly till 5 years. Results: We included our first 60 saccular
aneurysms (57 patients with 60 aneurysms) for whom endovascular coiling was done. Fifty seven of our patients
(95%) had ruptured aneurysm while 3 (5%) had unruptured aneurysms (asymptomatic). Fifty five aneurysms
(91.7%) were small (< 10 mm) and only 5 (8.3%) were between 11-15 mm. Thirty three (55%) had narrow neck
while 27 (45%) had a wide neck. We succeeded to achieve total occlusion of the aneurysm in 49/60 cases (81.6%),
neck remnant was left in 6 cases (10%), incomplete occlusion was done in two cases (3.3%). In 3 cases (5%) we
failed to occlude the aneurysm. Balloon remodling and coiling was used in 6 patients (10%) while self-expandable
stent and coiling was used in two patient (3.3%). We faced 3 clinical complications (5%) that resulted in
neurologic deficit. During long-term follow up (mean 31 +/-20.4 months) for the surviving patients, none of the
treated aneurysms suffered from rebleeding. MRA or angiography follow up for up to 5 years revealed persistent
total occlusion in 37/42 patients (88%), stable neck remnant in 3/42 patients (7.1%) for whom no further
treatment was required and major aneurysm recurrence in 2/42 patients (4.7%). Conclusion: Endovascular
coiling is a less invasive alternative to surgical clipping. For patients in good as well as poor clinical condition
with ruptured or unruptured aneurysms of either the anterior or posterior circulation, there is firm evidence that if
the aneurysm is considered suitable for surgical clipping and endovascular treatment, coiling is associated with a
better outcome. (Egypt J. Neurol. Psychiat. Neurosurg., 2007, 44(2): 751-769)

INTRODUCTION onset and poor outcome in SAH1,2. Aneurysmal
subarachnoid hemorrhage has a 30-day mortality

rate of 45 percent. An estimated 30 percent of
Although subarachnoid hemorrhage (SAH)
survivors will have moderate-to-severe disability3.
comprises only 1% to 7% of all strokes, the loss
However, unlike other stroke subtypes, the
of productive life years in the general population
incidence of SAH did not significantly change
from SAH is comparable to that of cerebral
over the last decades1,2,3. In the most recent
infarction because of the relatively young age of
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Egypt J. Neurol. Psychiat. Neurosurg. Vol. 44 (2) – July 2007
overview of 14 longitudinal and 23 case-control Coiling had been introduced as an
studies of risk factors for SAH published in experimental procedure for patients who were not
English from 1966 through March 2005, it was good candidates for surgery. After almost a decade
concluded that smoking, hypertension, and of increased use and evaluation, endovascular
excessive alcohol are the most important risk coiling has proved to be a safe and durable
factors for SAH4. There is also evidence that alternative to the traditional neurosurgical treatment
genetic factors play an important role in the of craniotomy and clip ligation (clipping)7. Coiling
pathogenesis of SAH5. has now surpassed clipping as the primary method
Intracranial aneurysms are common lesions; of treatment for intracranial aneurysms in some
autopsy studies indicate prevalence in the adult centers. Since the Guglielmi detachable coil for the
population between 1 and 5 percent, which treatment of intracranial aneurysms was approved
translates to 10 million to 12 million persons in in 1995 by the Food and Drug Administration
the United States. Fortunately, most aneurysms (FDA), an estimated 150,000 patients have been
are small, and an estimated 50 to 80 percent of all treated with this device9.
aneurysms do not rupture during the course of a This is an observational study to report the
person’s life time6. The estimated incidence of results of our first 60 saccular aneurysms (57
subarachnoid hemorrhage from a ruptured patients with 60 aneurysms) for whom
intracranial aneurysm in the United States is 1 endovascular coiling was performed.
case per 10,000 persons, yielding approximately
27,000 new cases of subarachnoid hemorrhage SUBJECTS AND METHODS
each year7.

During endovascular occlusion with the use
Subjects
of detachable coils (coiling), a microcatheter is
Between January 2002 and December 2006,
advanced into the aneurysm, and detachable coils
we performed endovascular coiling for 60
of various sizes and shapes are deployed to stop
saccular aneurysms (57 patients with 60
blood from filling the aneurysm (Fig. 1).
aneurysms) fulfilling the following criteria:

Inclusion criteria:
* Symptomatic, presenting with acute
subarachnoid hemorrhage (Hunt and Hess
grade I-IV)
* Asymptomatic, ≥7 mm in size in the anterior
circulation or < 7 mm in size in the posterior
circulation in patients < 60 y old Or with
personal or family history of subarachnoid
hemorrhage.

Exclusion criteria:
Hunt and Hess Grade V (deep Coma,
decerebrate posturing, moribund)

Methods
All patients underwent:
* Clinical assessment together with Hunt and
Hess scale (H&H scale) and modified
Fig. (1): Endovascular occlusion of an aneurysm Rankin Scale (mRS). This was done before
of the posterior communicating artery with coiling, after one month, 3 months, 6 months
guglielmi detachable coils. of coiling and then yearly thereafter.
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Hany Zakieldine
* Laboratory investigations: complete blood complete occlusion or near complete occlusion
count, coagulation profile, liver and renal (neck remnant). Neck remnant was defined as the
function tests, fasting and post-prandial persistence of any portion of the original defect of
blood sugar. the arterial wall as seen on any single projection
* CT scan brain +/- CSF analysis. but without opacification of the aneurysmal sac.
* Six vessels digital subtraction cerebral Incomplete occlusion was defined as persistence
angiography followed by endovascular of residual opacification in the aneurysm sac10. In
coiling of the aneurysm. cases of wide neck aneurysm, balloon assisted or
* Follow up MRA brain (3D time of flight; stent assisted coiling was done. Placement of the
3TOF) or DSA was done after 6 months and balloon or stent across the aneurysm wide neck
then yearly till 5 years. prevents coils from bulging out of the aneurysm.
In presence of severe vasospasm local intra-
Description of the procedure arterial injection of vasodilator drugs (nimodipine,
All procedures were carried out via puncture nitroglycerine or papaverine) was done.
of the right or left femoral artery. With the use of
a 5F diagnostic catheter both internal carotid Procedural success was defined as:
arteries (ICAs), external carotid arteries (ECAs) * To succeed to achieve total or near total
and vertebral arteries (VAs) were selectively occlusion of the aneurysm (neck remnant).
catheterized. When a saccular aneurysm was * Absence of complications.
detected, a complete study of its angiographic
features was done using different projections to During follow-up, the recurrence was
determine its site, direction, size, dome to neck qualified as major if it resulted in saccular
ratio (ie. narrow versus wide neck), presence of a opacification of the aneurysm sac and its size
functional branch arising from the aneurysm, would theoretically permit re-treatment with
presence of a daughter aneurysm arising from the coils10.
primary sac and presence of vasospasm.
Wide neck aneurysm was defined as a dome RESULTS
to neck ratio <2:1. Vasospasm was graded as mild

(less than 50% lumen reduction), moderate (50-
Our study included our first 60 saccular
70% lumen reduction) and severe (more than 70%
aneurysms (57 patients with 60 aneurysms; three
lumen reduction)10. If more than one aneurysm
patients had two aneurysms) for whom
were found, the symptomatic one was treated first.
endovascular coiling was done. They were 32
Symptomatic aneurysm was determined according
males (53%) and 28 females (47%). Their age
to the distribution of blood in the CT scan,
ranged from 15 y to 82 y with a mean of
presence of focal vasospasm, size of the
46.7±13.6 years. Risk factors included,
aneurysm, multi-lobed aneurysm and presence of
hypertension in 34 (56%), smoking or ex-smoking
daughter aneurysm.
in 17 (28.3%). On the other hand, diabetes
After having studied the aneurysm to be
mellitus was found in 8 (13%) and ischemic heart
treated, systemic heparinization was given and the
disease was found in 3 (5%) (Table 1).
internal carotid or vertebral artery was selectively
Fifty seven of our patients (95%) had
engaged by using a proper 6F guiding catheter.
ruptured aneurysm causing subarachnoid
Then, using the coaxial system, selective
hemorrhage while 3 (5%) had unruptured
catheterization of the aneurysm was done using
aneurysms (asymptomatic). Of the patients
the microcatheter and then packing of its lumen
presenting with subarachnoid hemorrhage, 23
was done using detachable platinum coils until its
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Egypt J. Neurol. Psychiat. Neurosurg. Vol. 44 (2) – July 2007
(40.3%) had mild symptoms (H & H scale I-II), We succeeded to achieve total occlusion of
22 (38.5%) had moderate symptoms (H & H scale the aneurysm in 49/60 cases (81.7%), neck
III) while 12 (21%) had severe symptoms (H&H remnant was left in 6 cases (10%), incomplete
scale IV). Their CT scan revealed no or small occlusion was done in two cases (3.3%). Among 3
amount of subarachnoid hemorrhage (Fisher grade of those where a neck remnant was left and one of
I-II) in 8 patients (14%), moderate amount of the two cases with incomplete occlusion, this was
subarachnoid hemorrhage (Fisher grade III) in 25 done intentionally to preserve an important branch
patients (43.8%) and large amount of arising from the neck. The remaining 3 cases with
subarachnoid hemorrhage (Fisher grade IV) in 24 a left neck remnant were done early during our
patients (42%) (Table 2). work when soft balloon or stent for remodling was
The 3 patients with unruptured aneurysm not available. In 3 cases (5%) we failed to occlude
that was coiled presented with subarachnoid the aneurysm. All 3 were tiny aneurysm (2 mm)
hemorrhage and had two aneurysms, one and it was not possible to catheterize the
symptomatic and the second unruptured that was aneurysm in two of them while the third was a
more the 4 mm in size, terminal type rather than diffuse ectasia of the upper MCA branch with no
side wall. In addition, they were less than 60 years neck. Balloon remodling and coiling was used in
old with no life threatening diseases. 6 patients (10%) while self-expandable stent and
Concerning the localization of the coiling was used in two patient (3.3%) (Table 4).
aneurysms, 27 (45%) were anterior We faced 3 clinical complications (5%) that
communicating or anterior cerebral aneurysms resulted in neurologic deficit. Two were due to
(ACoA/ACA), 15 (25%) were middle cerebral thromboembolic complications and one was due
artery bifurcation aneurysms (MCA), 8 (13.3%) to branch occlusion. One of the thromboembolic
were posterior communicating aneurysms complications was due to the use of biologically
(PCoA), 4 (6.7%) were posterior inferior active coils that are more thrombogenic. We faced
cerebellar aneurysms (PICA), 1 (1.7%) no procedural related mortality (Table 5).
pericallosal aneurysm, 1 (1.7%) ICA bifurcation Delayed ischemia and cerebral infarction
aneurysm, 1 (1.7%) carotido-ophthalmic secondary to vasospasm (procedural unrelated)
aneurysm, 1 (1.7%) basilar tip aneurysm, 1 (1.7%) occurred in 10 patients (16.7%). Hydrocephalic
basilar trunk aneurysm, 1 (1.7%) posterior changes necessitating ventriculo-peritoneal shunt
cerebral artery aneurysm (PCA) (table 3). insertion occurred in 8 patients (13.3%).
Concerning the angiographic features of the The outcome upon discharge from hospital
treated aneurysms, 30 (50%) were less than 5 mm was good (mRS 0-2) in 44 patients (73.3%), faire
in size, 25 (41.7%) were between 5-10 mm. (mRS 3) in 5 patients (8.3%) and poor (mRS 4) in
Hence, 91.7% of our aneurysms were small ones 2 patients (3.3%). On the other hand 9 patients
and only 5 (8.3%) were between 11-15 mm. (15%) died due to the complications of the
Thirty three (55%) had a narrow neck while 27 subarachnoid hemorrhage (Table 6). Statistically
(45%) had a wide neck. Branch arising from the significant correlation was found between the
neck or aneurysm sac was seen in 10 cases clinical severity of subarachnoid hemorrhage
(16.6%). Vasospasm during angiography before (Hunt and Hess scale), occurrence of delayed
coiling was detected in 14 cases (23.3%; mild in 2 cerebral ischemia secondary to vasospasm
cases, moderate in 4 and severe in 8 cases). (procedural unrelated), occurrence of
Vasospasm was treated with local intra-arterial hydrocephalus necessitating ventriculo-peritoneal
injection of vasodilator drugs and did not prevent shunting and the outcome upon discharge
access and treatment of the aneurysm (table 3). (p<0.001). Eighty six percent of patients
presenting with mild subarachnoid hemorrhage
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Hany Zakieldine
(H&H scale I-II) and eighty one percent of those 25%) developed a stable neck remnant for which
with moderate subarachnoid hemorrhage (H&H no further treatment was required. On the other
scale III) had good outcome. In contrast, only hand, one patient (1/4 patients, 25%) developed
25% of patients presenting with severe major aneurysm recurrence and a second session
subarachnoid hemorrhage (H & H scale IV) had of embolization is being prepared for her. In this
good outcome. On the other hand, there was no patient only partial aneurysm coiling was done
correlation between the age (<50 y versus >50 y), during the first session of coiling (Table 8).
the amount of blood on CT scan (Fisher grade), Statistically significant correlation was found
the aneurysm site, the dome/ neck ratio, and the between major aneurismal recurrence and
final outcome (Table 7). Concerning the 3 patients immediate angiographic results after coiling (i.e.
that we failed to occlude their aneurysm, 2 of total or near total vesus incomplete occlusion)
them died from the complications of their initial (p<0.001). On the other hand, there was no
subarachnoid hemorrhage despite that one of them correlation between major aneurismal recurrence
performed surgical wrapping of the aneurysm. and aneurysm site, size and dome/neck ratio
The third patient was followed for 6 months with (Table 9).
no rebleeding. Two of our patients were particularly
During long-term follow up (mean 31 +/- interesting. The first was a female patient 18 years
20.4 months, minimum of 6 months and maximum old who developed acute subarachnoid
of 72 months) of the surviving 51 patients, drop hemorrhage (H & H II) secondary to a wide neck
out were 6 patients (6/51 patients, 11.7%). In Lt posterior cerebral artery (PCA) aneurysm
addition, 3 patients refused to do follow-up MRA measuring 8 x 5 mm. Mass effect from this
or angiography, two of them were 73 and 82 years aneurysm resulted in Rt sided ataxic hemiparesis
old. None of the treated aneurysms suffered from and a complete Lt oculomotor nerve palsy. A self
rebleeding. MRA or angiography follow up for up expandable flexible stent was placed in front of
to 5 years revealed persistent total occlusion in the aneurysm neck then through the mesh of the
37/42 patients (88%), stable neck remnant in 3/42 stent a microcatheter was advanced into the
patients (7.1%) for whom no further treatment was aneurysm and coiling was performed. The
required and major aneurysm recurrence in 2/42 presence of the stent prevented bulging of the
patients (4.7%). Of the small aneurysms (<10 coils out from the aneurysm and dense packing
mm) with narrow neck, only one patient (1/22 could be achieved. Owing to stopping the pulsetile
patients, 4.5%) developed major aneurysm flow in the aneurysm after filling its lumen
recurrence. In this patient, only partial aneurysm followed by its fibrosis and shrinkage, the mass
coiling could be achieved immediately after effect gradually improved over the next 3 months
coiling since she had a Rt MCA trifurcation (Fig. 2). The second patient was a 20 years old
aneurysm with two of the MCA branches were female who developed acute subarachnoid
arising from the aneurysm sac itself. Therefore, hemorrhage (H&H II) secondary to a wide neck
partial coiling was done to preserve the flow in Rt middle cerebral artery (MCA) trifurcation
these branches. A second session was done for aneurysm measuring 7 x 5 mm. Two of the three
this patient 6 months later where only a neck MCA trifurcation branches were arising from the
remnant was left and the latter remained stable aneurysm neck. Hence balloon remodling was
thereafter. Of the small aneurysms (<10 mm) with done to protect these branches during coiling of
wide neck, two patients (2/16 patients, 12.5%) the aneurysm. This technique allowed us to
developed a stable neck remnant for which no achieve dense packing of the aneurysm with
further treatment was required. Of the large preservation of the MCA branches (Fig. 3).
aneurysms (>10 mm), one patient (1/4 patients,
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Egypt J. Neurol. Psychiat. Neurosurg. Vol. 44 (2) – July 2007
Table 1. Baseline characteristics and medical history.

No %
Male 32 53
Female 28 47
Age mean 46.7±13.6 y
Hypertension 34 56
Smoking 17 28.3
Diabetes Mellitus 8 13
Ischemic Heart Disease 3 5

Table 2. Presentation and severity of clinical picture and CT scan.

No %
Ruptured aneurysm (SAH) 57 95
Asymptomatic 3 5
Severity of SAH
Hunt & Hess Scale I-II 23 40.3
Hunt & Hess Scale III 22 38.5
Hunt & Hess Scale IV 12 21
CT scan grading
Fisher grade I-II 8 14
Fisher grade III 25 43.8
Fisher grade IV 24 42

Table 3. Angiographic characteristics of the aneurysms.

No %
Localization of aneurysms
ACoA/ACA 27 45
MCA 15 25
PCoA 8 13.3
PICA 4 6.7
Pericallosal 1 1.7
ICA bifurcation 1 1.7
Carotido-ophthalmic 1 1.7
Basilar tip 1 1.7
Basilar trunk 1 1.7
PCA 1 1.7
Size of aneurysms
Less than 5 mm 30 50
5-10 mm 25 41.7
More than 10 mm 5 8.3
Size of neck of aneurysm (dome/neck ratio)
Narrow neck 33 55
Wide neck 27 45
Branch arising from neck or sac 10 16.6
Vasospasm during initial angiography 14 23.3
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Hany Zakieldine
Table 4. Procedural details and success.

No %
Total occlusion 49 81.7
Neck remnant 6 10
Incomplete occlusion 2 3.3
Failed coiling 3 5
Balloon remodling 6 10
Self-expandable stent 2 3.3

Table 5. Complications.

No %
Thromboembolic complications 2 3.3
Branch occlusion 1 1.6
Procedural related mortality 0 0

Table 6. Outcome upon discharge.

No %
mRS 0-2 44 73.3
mRS 3 5 8.3
mRS 4 2 3.3
Death 9 15

Table 7. Factors related to the outcome upon discharge.

Variables P value Significance
Age (<50 vs >50 y) 0.394 NS
H&H scale <0.001 S
Fisher CT scan grade 0.771 NS
Aneurysm site 0.496 NS
Dome/ neck ratio 0.808 NS
Delayed cerebral ischemia secondary to vasospasm (procedural unrelated) <0.001 S
Hydrocephalic necessitating ventriculo-peritoneal shunting <0.001 S

Table 8. Long-term follow-up.

No %
Rebleeding 0 0
Persistent total occlusion 37 88
Stable neck remnant 3 7.1
Major aneurysm recurrence 2 4.7

Table 9. Factors related to major aneurysm recurrence.

Variables P value Significance
Aneurysm site 0.6 NS
Aneurysm size 0.08 NS
Dome/ neck ratio 0.33 NS
Immediate angiographic results <0.001 S

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A B

C D

Fig. (2): (A) CT scan showing the Lt PCA aneurysm compressing the midbrain. (B) Digital subtraction
angiography showing the Lt PCA wide neck aneurysm. (C) Digital subtraction angiography after stent
supported coiling of the aneurysm resulting in its total occlusion. (D) Self expandable stent and coil mass.
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Hany Zakieldine

A B

C D

E F
Fig. (3): (a and b) Wide neck Rt MCA trifurcation aneurysm with two of the MCA branches arising from the
neck. (c and d) Balloon placed in one of the upper MCA branches protecting the MCA trifurcation while
coiling is performed. (e and f) After coiling of the aneurysm resulting in its total occlusion.
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Egypt J. Neurol. Psychiat. Neurosurg. Vol. 44 (2) – July 2007
DISCUSSION endovascular repair can be very good19,20,21
although it does not appear to be cheaper than

surgery at the present time22. Overall procedural
For ruptured aneurysms, early treatment
morbidity and mortality rates for coiling have
within 24 to 72 hours has been recommended
been reported as 3.7 to 5.3 percent and 1.1 to 1.5
because the risk of subsequent rupture is high,
percent, respectively19,21,23,24.
with approximately 20% risk of rerupture in the
Overall clinical outcome of endovascular
first 2 weeks after subarachnoid hemorrhage11.
treatment was related to the immediate
Each additional rupture substantially increases the
postprocedural angiographic result, which in turn
risk of mortality and morbidity. Treatment has
was related to microcatheter stability, aneurysm
also been recommended for most of the
geometry and aneurysm neck diameter25.
unruptured aneurysms, although there is
Several retrospective comparative studies
uncertainty about treatment of some small
comparing aneurysm coiling to clipping16,17,26
aneurysms <7 mm because their risk of rupture
suggest that despite its attendant risks, treating
appears low12.
most ruptured and unruptured intracranial
All ruptured aneurysms in patients with Hunt
aneurysms with detachable coils appears to be
and Hess grades I to IV are treated early. There is
safer than clipping, at least during the
debate about how to treat patients with the most
perioperative period. It was concluded that for
severe grade, Hunt and Hess grade V. The
patients in good clinical condition with ruptured
historically high incidence of poor outcome
aneurysms of either the anterior or posterior
despite treatment has prompted the suggestion of
circulation, there is firm evidence that if the
conservative management unless clinical
aneurysm is considered suitable for surgical
improvement occurs. However, recent evidence
clipping and endovascular treatment, coiling is
supports the use of aggressive therapy for most of
associated with a better outcome. For patients in
these patients, including placement of a
poor clinical grade, there is no reliable
ventricular drain and securing the aneurysm by
randomized evidence comparing the risks and
clipping or coiling13.
benefits of coiling versus clipping. Because
In 1991, Guido Guglielmi was the first to
coiling is less invasive than surgery, also in
describe the technique of occluding aneurysms
patients with poor clinical condition, coiling
from an endovascular approach with electrolytic
seems the preferred option27. More robust data
detachable platinum coils, termed Guglielmi
favoring the safety of coiling over clipping for
detachable coils (GDCs) thereby excluding it from
aneurysms presenting with subarachnoid
the circulation14,15. As clinical experience with
hemorrhage came from a large, multicenter
this technique has increased and coil design has
prospective study conducted in England. In the
improved, coil embolization has been used with
International Subarachnoid Aneurysm Trial
increasing frequency even in patients who could
(ISAT) 28, 2143 primarily good-grade patients
be treated by conventional surgical clipping16,17.
presenting with a ruptured aneurysm (mostly small
Furthermore, some centers are treating patients
<10mm and located in the anterior circulation)
with surgical clipping only if they cannot be
were prospectively randomly assigned to either
treated primarily by endovascular coil
clipping or coiling. Recruitment into the trial was
embolization therapy18.
stopped, since the relative risk (22.6 percent) and
Endovascular treatment, a less stressful
the absolute risk (6.9 percent) of dependency and
alternative to clipping has been proven to be
death in the group assigned to coiling was clearly
effective in preventing rebleeding after
reduced as compared with that in the group
subarachnoid hemorrhage due to aneurismal
assigned to clipping. These observations were
rupture. Accumulating clinical experience
upheld in the one-year follow-up report on the
confirms that early and midterm results after
760