Endovascular Treatment of Very Large and Giant Intracranial Aneurysms: Comparison between Reconstructive and Deconstructive Techniques—A Meta-Analysis
========================================================================================================================================================

* F. Cagnazzo
* D. Mantilla
* A. Rouchaud
* W. Brinjikji
* P.-H. Lefevre
* C. Dargazanli
* G. Gascou
* C. Riquelme
* P. Perrini
* D. di Carlo
* A. Bonafe
* V. Costalat

## Abstract

**BACKGROUND:** The safety and efficacy of reconstructive and deconstructive endovascular treatments of very large/giant intracranial aneurysms are not completely clear.

**PURPOSE:** Our aim was to compare treatment-related outcomes between these 2 techniques.

**DATA SOURCES:** A systematic search of 3 data bases was performed for studies published from 1990 to 2017.

**STUDY SELECTION:** We selected series of reconstructive and deconstructive treatments with >10 patients.

**DATA ANALYSIS:** Random-effects meta-analysis was used to analyze occlusion rates, complications, and neurologic outcomes.

**DATA SYNTHESIS:** Thirty-nine studies evaluating 894 very large/giant aneurysms were included. Long-term occlusion of unruptured aneurysms was 71% and 93% after reconstructive and deconstructive treatments, respectively (*P* = .003). Among unruptured aneurysms, complications were lower after parent artery occlusion (16% versus 30%, *P* = .05), whereas among ruptured lesions, complications were lower after reconstructive techniques (34% versus 38%). Parent artery occlusion in the posterior circulation had higher complications compared with in the anterior circulation (36% versus 15%, *P* = .001). Overall, coiling yielded lower complication and occlusion rates compared with flow diverters and stent-assisted coiling. Complication rates of flow diversion were lower in the anterior circulation (17% versus 41%, *P* < .01). Among unruptured lesions, early aneurysm rupture (within 30 days) was slightly higher after reconstructive treatment (5% versus 0%, *P* = .08) and after flow diversion alone compared with flow diversion plus coiling (7% versus 0%).

**LIMITATIONS:** Limitations were selection and publication biases.

**CONCLUSIONS:** Parent artery occlusion allowed high rates of occlusion with an acceptable rate of complications for unruptured, anterior circulation aneurysms. Coiling should be preferred for posterior circulation and ruptured lesions, whereas flow diversion is relatively safe and effective for unruptured anterior circulation aneurysms.

## ABBREVIATIONS:

BAC
:   balloon-assisted coiling
PAO
:   parent artery occlusion
PRISMA
:   Preferred Reporting Items for Systematic Reviews and Meta-Analyses
SAC
:   stent-assisted coiling

Very large (diameter of ≥2 cm) and giant (diameter of ≥2.5 cm) intracranial aneurysms remain challenging lesions to treat by both surgical and endovascular approaches. Because of their size, intraluminal thrombosis, neck dimension, and involvement of neural structures, giant aneurysms are often associated with high rates of recurrence and treatment-related morbidity and mortality.1,2 Treatment should result in the following3⇓–5: 1) protection against aneurysm rupture, 2) prevention of thromboembolic complications, 3) improvement of mass effect, and 4) prevention of aneurysm growth. The endovascular strategies can be divided into 2 groups: 1) selective aneurysm treatment with coiling, balloon-assisted coiling (BAC), stent-assisted coiling (SAC), and flow diversion (reconstructive techniques); and 2) parent artery occlusion (PAO) (deconstructive technique). Both techniques have limitations: selective aneurysm embolization is usually associated with high recurrence rates, with important differences in the various available techniques, while, PAO is potentially associated with long-term complications related to vessel sacrifice.4,6,7 We performed a meta-analysis of all published series examining endovascular treatments of very large and giant aneurysms with the aim of clarifying the following: 1) occlusion rate, 2) treatment-related complications, and 3) clinical outcome of reconstructive and deconstructive techniques.

## Materials and Methods

### Literature Search

A comprehensive literature search of PubMed, Ovid MEDLINE, and Ovid EMBASE was conducted for studies published from 1990 to September 2017. Guidelines for Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA)8 were followed. The detailed search strategy is reported in On-line Table 1. The inclusion criteria were the following: studies reporting very large (diameter of ≥2 cm) and giant (diameter of ≥2.5 cm) aneurysms treated endovascularly2 (coiling/BAC, SAC, flow diversion, and PAO). Exclusion criteria were the following: 1) studies with <10 patients, 2) review articles, 3) studies published in languages other than English, and 4) treatment with Onyx (Covidien, Irvine, California) or covered stents. In cases of overlapping patient populations, only the series with the largest number of patients or most detailed data were included. Two reviewers independently selected the included studies, and a third author solved discrepancies.

### Data Collection

From each study, we extracted the following: 1) treatment-related outcomes, 2) long-term occlusion rates, 3) incidence of early (within 30 days) and late (after 30 days) ruptures after treatment, 4) rate of recurrence, 5) mean and median times between treatment and recurrence, and 6) rate of retreatment. Treatment-related outcomes were dichotomized into 2 groups: reconstructive techniques (coiling/BAC, SAC, flow diversion alone, and flow diversion plus coiling) and deconstructive techniques. In addition, the influence of 4 parameters (age, aneurysm size, location, and shape) on the occlusion and complication rates was analyzed. Finally, good outcome was defined as a modified Rankin Scale score of 0–2 or a Glasgow Outcome Score of 4–5, or it was assumed if the study used terms such as “no morbidity,” “good recovery,” or “no symptoms.”

### Outcomes

The primary objectives of this meta-analysis were to compare reconstructive and deconstructive techniques for the following outcomes: 1) aneurysm occlusion rate, 2) treatment-related complications, and 3) clinical outcome. Among the reconstructive group, complications and angiographic outcomes were compared between coiling and flow diversion.

### Quality Scoring

The Newcastle-Ottawa Scale9 was used to assess the quality of the included studies (On-line Table 2). “High-quality” studies were defined on the basis of the following: 1) the presence of a study and imaging protocol, 2) defined inclusion and exclusion criteria, 3) detailed information about treatment-related outcomes, and 4) adequate length of follow-up. Adequate length of follow-up was considered approximately 12 months because most of the reported outcomes (treatment-related complications and angiographic outcomes) occurred within this time. The quality assessment was performed by 2 authors independently, and a third author solved discrepancies. Studies receiving ≥6 stars are considered “high-quality” (score range from 0 to 9).

### Statistical Analysis

We estimated, from each cohort, the cumulative prevalence and 95% confidence interval for each outcome. Event rates were pooled across studies with a random-effects meta-analysis. Heterogeneity across studies was evaluated using the I2 statistic: An I2 value of >50% suggests substantial heterogeneity. We also extracted a 2 × 2 table to calculate *P* values for the comparisons among the results. Meta-regression was not used in this study. Statistical analysis was performed using OpenMeta[Analyst] ([http://www.cebm.brown.edu/openmeta/](http://www.cebm.brown.edu/openmeta/)).

## Results

### Literature Review

Studies included in our meta-analysis are summarized in On-line Table 2. The search flow diagram is shown in the On-line Figure. A total of 39 studies and 894 giant and very large intracranial aneurysms were included in our review. Mean radiologic and clinical follow-ups were 26 months (range, 6–66 months; median, 21 months) and 34 months (range, 6–20 months; median, 28 months).

### Quality of Studies

Overall, 20 studies were rated “high quality.” All the high-quality articles reported detailed information about aneurysm occlusion rates, treatment-related complications, factors related to occlusion and complications, and adequate length of follow-up. Three articles were prospective studies, 6 series were obtained from a prospectively maintained data base, and 30 articles were retrospective.

### Patient Population and Treatment Characteristics

Detailed information about patient populations is reported in On-line Table 3.

Overall, 75% (95% CI, 72%–78%) and 25% (95% CI, 22%–27%) of aneurysms were treated with reconstructive and deconstructive techniques, respectively. About 70% of unruptured aneurysms were treated with reconstructive techniques. Among these patients, coiling/BAC was performed in 40% of cases; SAC, in about 16% of cases; and flow diversion, in 42% of patients. A deconstructive approach was performed in about 30% of unruptured aneurysms. Ruptured aneurysms were treated with coiling and PAO in 75% and 25% of cases, respectively. No acutely ruptured large and giant aneurysms were treated by flow diversion.

Balloon test occlusion was performed in about 86% of patients before PAO. In about 4% of patients, the occluded vessel was a nondominant vertebral artery and balloon test occlusion was not necessary. In 10% of cases (2 articles), there was not enough information about balloon test occlusion (On-line Table 2). About 70% of deconstructive treatments in the posterior circulation were performed in the basilar artery/posterior cerebral artery, whereas 30% were performed in the vertebral artery.

### Angiographic Outcomes

#### Unruptured Aneurysms.

The rate of long-term complete/near-complete occlusion was 71% (95% CI, 60%–81%) and 93% (95% CI, 89%–98%) after reconstructive and deconstructive treatments, respectively (*P* = .003) (Table 1). The rate of recanalization was higher after reconstructive treatment (40%) compared with the deconstructive technique (5%) (*P* = .001). Similarly, the rate of retreatment was significantly higher among the reconstructive group (32% versus 4%) (*P* = .001). Early and late aneurysm ruptures after reconstructive techniques were 5% and 3%, respectively. No cases of rupture were described after PAO.

View this table:
[Table 1:](http://www.ajnr.org/content/39/5/852/T1)

Table 1: 
Angiographic outcomes for unruptured and ruptured very large/giant intracranial aneurysms—comparison between reconstructive and deconstructive treatments

#### Ruptured Aneurysms.

There were comparable rates of complete/near-complete occlusion (72% versus 80% after reconstructive and deconstructive treatments, respectively) (*P* = .5). Aneurysm recanalization was 47% after reconstructive and 22% after deconstructive techniques (*P* = .1). There was a significantly higher rate of retreatment after reconstructive compared with deconstructive treatments (48% versus 22%) (*P* = .007). The rate of early aneurysm rupture after coiling was 8%, whereas no cases were described after deconstructive treatment.

### Treatment-Related Complications and Clinical Outcomes

#### Unruptured Aneurysms.

Overall, treatment-related complications were 30% (95% CI, 22%–37%) and 16% (95% CI, 7%–25%) after reconstructive and deconstructive treatments (*P* = .05) (On-line Table 4). Similarly, permanent complications were higher among the reconstructive group (15% versus 8.6%, *P* = .01). Most complications were related to ischemic events (15% and 11% among reconstructive and deconstructive groups, respectively). Worsening of mass effect was comparable between reconstructive and deconstructive treatments (1.7% versus 3.5%). Finally, the rate of hemorrhagic complications was higher after reconstructive techniques (6%) compared with PAO (2%) (*P* = .03). There was no significant difference in mortality rates between the 2 groups (9% versus 6%, *P* = .35).

The rates of good neurologic outcome were 80% and 89% after reconstructive and deconstructive treatments, respectively (*P* = .1). During follow-up, mass effect symptoms were improved in about 48% of patients after reconstructive treatments and in 77% of patients after PAO (*P* = .02).

#### Ruptured Aneurysms.

The overall rates of complications and permanent complications were slightly higher after PAO (38% and 29%) compared with coiling (34% and 20%). The incidence of ischemic events was slightly higher after deconstructive compared with reconstructive treatments (33% versus 18.8%, *P* = .3), as was worsening of mass effect (14% versus 7%, *P* = .2). Hemorrhagic complications were higher after coiling compared with PAO (17% versus 9%, *P* = .5). The rate of good neurologic outcome was close to 60% for both types of treatment. Improvement of compressive symptoms was reported in 24% of reconstructive cases, whereas no data were available among the deconstructive group.

### Factors Related to Occlusion and Complication Rates after Treatment

#### Reconstructive Group.

Differences in occlusion rates were not statistically significant in relation to aneurysm size (less or more than 3 cm), anterior-versus-posterior circulation, and saccular-versus-fusiform aneurysms. However, there was a slightly higher incidence of occlusion among younger patients (younger than 60 years) compared with elderly patients (older than 60 years) (82% versus 71%) (*P* = .09, OR = 1.97). The incidence of complications was similar among groups of age, aneurysm size, and anterior-versus-posterior circulation. Among saccular aneurysms, the rate of complications was 23% (95% CI, 2%–40%), whereas no data were available for fusiform aneurysms (On-line Table 5).

#### Deconstructive Group.

Complete/near-complete aneurysm obliteration was higher among younger patients (95.9% versus 78%) (*P* = .007, OR = 2.5). No differences in occlusion rates were found in relation to aneurysm size, location, and shape. Complication rates were comparable between younger and older patients and aneurysm sizes, whereas posterior circulation aneurysms treated with PAO showed higher rates of complications (36%) compared with anterior circulation aneurysms (15%) (*P* = .001, OR = 3.6). Although few studies were available for the analysis, complications were statistically similar between fusiform and saccular aneurysms (On-line Table 5).

### Comparison among Coiling/BAC, SAC, and Flow Diversion for the Treatment of Unruptured Aneurysms

Complete/near-complete occlusion was 59% and 73% after coiling/BAC and SAC, respectively (*P* = .3) (On-line Table 6). Flow-diversion treatment resulted in 72% occlusion rates, with comparable rates between treatment with flow diverter alone versus flow diverter with adjunctive coils (75% versus 70%, respectively). The rates of early aneurysm rupture after coiling and SAC were approximately 6% and 9% (*P* = .5), whereas 7% of cases were reported after flow diversion alone, and no cases were described after flow diversion with adjunctive coils. The rate of late aneurysm rupture was 7% after coiling/BAC, whereas there were no cases of late rupture after SAC and flow diversion. The overall rate of treatment-related complications was higher after SAC (39%) compared with coiling/BAC (20%) (*P* = .001). Complications after flow diversion were 29%, and there were no significant differences between flow diversion alone and flow diversion plus coiling (32% versus 26%, *P* = .8). Treatment-related complications among anterior circulation aneurysms were slightly lower compared with posterior circulation aneurysms after coiling/BAC (15% versus 20%, *P* = .7) and SAC (38% versus 43%, *P* = .9), whereas flow diversion was associated with significantly lower rates of complications in the anterior circulation (17% versus 41%, *P* = .02). The most common complications were ischemic events, particularly among the SAC group (32%). Worsening of mass effect was close to 6% after coiling and SAC, whereas it was lower after flow diversion (1.6%). Hemorrhagic complications were between 5% and 10% among the different treatment groups. Overall, the rate of good neurologic outcome was between 60% and 72%.

### Study Heterogeneity

High rates of heterogeneity were reported in the following: treatment-related complications, improvement of mass effect among unruptured lesions, rates of occlusion and recanalization among reconstructive treatments of unruptured aneurysms, and factors related to complications and aneurysm occlusion.

## Discussion

Our meta-analysis of nearly 900 very large/giant intracranial aneurysms treated endovascularly shows important differences between reconstructive and deconstructive techniques. Overall, among unruptured aneurysms, deconstructive treatments allowed higher rates of occlusion (93% versus 71%) and lower rates of complications (16% versus 30%), compared with reconstructive techniques. However, among posterior circulation aneurysms, treatment-related morbidity was not negligible after PAO (36%). Coil embolization of unruptured lesions was associated with lower rates of complication and aneurysm occlusion (20% and 59%) compared with SAC (39% and 73%) and flow diversion (29% and 72%). Most interesting, flow-diverter stents were significantly safer among anterior circulation aneurysms (17% versus 41% complications), whereas the safety of coiling and SAC was comparable for anterior and posterior circulation lesions. Although ruptured aneurysms were effectively treated with both techniques (70%–80% occlusion), reconstructive treatments were associated with a lower rate of complication and morbidity (34% and 20%) compared with PAO (38% and 29%). Younger patients had higher odds of aneurysm occlusion after reconstructive (OR = 1.9) and deconstructive treatments (OR = 2.5) compared with older patients. These findings are important, and they provide more information to guide the endovascular treatment/management of these lesions.

### Reconstructive Treatments

Although exclusion of aneurysms with preservation of the parent vessel should be the first option, complication rates of reconstructive treatments seem nonnegligible. We found 30% treatment-related complications with 15% morbidity after reconstructive treatments of giant unruptured aneurysms. Most complications were ischemic (15%): They may be related to the complexity of the procedure, longer duration of the treatment, and use of adjunctive devices (SAC, flow diverter and coiling, or multiple flow diverters).1,10 Ischemic events were particularly high after SAC (30%), which may be a reflection of a longer procedure time, technical challenges encountered during stent deployment, and the need for dual-antiplatelet therapy. According to our results, in a large series of 512 patients treated with coiling alone and SAC, Yang et al11 showed that larger aneurysm size was a predictor of procedural morbidity after SAC. In our study, the rate of complications after flow-diversion treatment ranged from 25% to 30%, without significant differences between flow diversion alone and flow diversion with adjunctive coils. This finding is in accordance with findings reported in other studies comparing the 2 groups of treatments.12 Most interesting, flow diversion was safe and effective among anterior circulation lesions, whereas it was associated with a high incidence of complications in the vertebrobasilar region. In the International Retrospective Study of Pipeline Embolization Device (IntrePED), among the subgroup of giant aneurysms, Kallmes et al13 reported 40% of complications after Pipeline treatment in the posterior circulation, compared with 23% in the anterior circulation. Among unruptured aneurysms, there was a trend toward higher rates of worsening of mass effect after coiling and SAC (6%) compared with flow diversion (1.6%), whereas the rates were comparable between reconstructive and deconstructive techniques.

Aneurysms presenting with mass effect are usually treated by a surgical approach (and decompression of the mass effect) with evacuation of the aneurysmal sac. However, our meta-analysis showed improvement of mass effect in about 50% and 77% of reconstructive and deconstructive treatments of unruptured aneurysms, respectively. Compressive symptoms in giant aneurysms seem to be a combination between direct compression/deformation of the neural structures and irritation caused by aneurysm sac pulsation. Accordingly, improvement leads independently to aneurysmal shrinkage because of the decreased pulsation, resolution of the perianeurysmal edema, and partial shrinkage.14 In a series of 19 aneurysms treated with coiling, Hassan and Hamimi14 reported 63% complete resolution of mass effect and 32% symptom improvement, without strict correlation with aneurysm shrinkage on the MR imaging.

Long-term occlusion of giant aneurysms is notoriously challenging after selective endovascular treatment,1,6 and the rates complete/near-complete occlusion are reported to be between 35% and 90%.1,3,15⇓–17 Our study, the largest to date, demonstrated roughly 70% complete/near-complete occlusion after reconstructive treatment, with 40% and 32% recanalization and retreatment, respectively. In addition, we found a higher rate of occlusion after flow diversion and SAC (72% and 73%) compared with coiling alone (59%). Although currently it is common practice to perform coil embolization of giant aneurysms in addition to flow diversion, no significant differences in occlusion rates were found between flow diverter alone and flow diverters plus coils. Most interesting, after reconstructive treatments, the occlusion rate seems to be slightly higher among younger patients (80% versus 70%, OR = 1.9) with smaller aneurysms in the anterior circulation. In general, reconstitution of the endothelial lining of the neck with thrombus organization inside the sac is an important factor related to stable aneurysm occlusion. In giant wide-neck aneurysms, insufficient stent wall apposition, low density of coil packing, and coil migration into the thrombotic wall can decrease the neoendothelization of the neck and the thrombotic process inside the sac.1,18,19

Postprocedural aneurysm rupture is a serious complication, and prior studies demonstrated a higher risk of rupture in giant aneurysms. After reconstructive treatments of unruptured lesions, we found 5% and 3% early and late aneurysm rupture. The incidence of rupture in the first 30 days was slightly higher in the ruptured group (8%, *P* = .08). Most interesting, the rate of rupture was comparable among coiling, SAC, and flow diversion. However, we found 7% early rupture (within 30 days) of aneurysms treated with flow diversion alone, and no cases of rupture in the group of lesions treated with adjunctive coils. These results support the recommendation to treat very large and giant aneurysms with concomitant coiling and flow diverters to prevent delayed ruptures. In a recent review of the literature, Rouchaud et al20 reported that 76% of the ruptures after flow diversion occurred in the first month: Giant aneurysms accounted for about 50% of ruptures, and 80% of lesions were not previously coiled.

Overall, the rate of good neurologic outcome was approximately 80% and 60% for unruptured and ruptured treated aneurysms.

### Deconstructive Treatments

Among unruptured aneurysms, PAO had lower complications (16%) and morbidity (9%) compared with reconstructive treatments. The most frequent complications were ischemic events (11%), whereas hemorrhagic complications seem to be significantly lower compared with reconstructive treatments (2% versus 6%, *P* = .03). Better results of PAO could be related to a careful patient selection with balloon test occlusion and rigorous postoperative management. In addition, deconstructive treatments allow better results in terms of improvement of mass effect compared with coiling or flow diversion (77% versus 48%, *P* = .02). In a series of 19 patients with giant aneurysms, Clarençon et al4 reported an 85% reduction of ocular symptoms, with a complete cure in 75% of cases. However, treatment-related outcomes after PAO in ruptured giant aneurysms were poor, with high rates of complications (38%) and morbidity (29%). The incidence of stroke seems to be high after PAO with SAH (33%). Several factors may explain the high rate of ischemic events in the acute phase: 1) difficulty in testing the hemodynamic tolerance to vessel occlusion, 2) management of the platelet antiaggregation therapy, 3) the hypercoagulability status after SAH, and 4) decreased blood flow compensation after cerebral vasospasm.

Most interesting, posterior circulation giant aneurysms treated with PAO had a remarkable complication rate compared with anterior circulation aneurysms (36% versus 15%, *P* = .001). Lubicz et al21 reported 40% early complications and 8% mortality after PAO of 13 giant vertebrobasilar aneurysms. The high morbidity rate can be related to the lower compliance of the posterior cranial fossa to mass effect lesions, high risk of injury to the perforating vessels, and difficulty in assessing the tolerance to occlusion of the vertebrobasilar territory. The size of the posterior communicating arteries represented a good predictor of long-term tolerance to basilar artery occlusion.22 However, giant vertebrobasilar aneurysms are challenging lesions with a poor prognosis after treatment, and survival as low as 20% after a few years if they are left untreated.22

Overall, long-term occlusion was achieved in about 90% of patients, with low recanalization and retreatment rates among unruptured lesions (5% and 4%, respectively), a low risk of rupture after treatment, and a high rate of good neurologic outcome.

### Strength and Limitations

Our study has limitations. There was substantial heterogeneity among the analyzed outcomes (I2 > 50%). The series are often small, retrospective, and single-institution experiences. Half of the reported studies were of low quality. Details of the antiplatelet therapy were infrequently specified. Finally, the small number of cases in some subgroups may not provide sufficient power to demonstrate a statistically significant difference in the rates of complications and occlusion among age groups and aneurysm size, location, and shape. However, although retrospective data are low in quality, our meta-analysis is the best available evidence to evaluate reconstructive and deconstructive treatments of very large/giant aneurysms.

## Conclusions

The treatment of very large and giant intracranial aneurysms remains extremely challenging. Sacrifice of the parent artery is a reasonable approach for complex unruptured, anterior circulation aneurysms, allowing high rates of occlusion with an acceptable rate of complications. Among reconstructive techniques, coiling should be preferred for the treatment of posterior circulation aneurysms and for ruptured lesions, whereas flow diversion is relatively safe and effective for unruptured anterior circulation aneurysms.

## Footnotes

*   Disclosures: Federico Cagnazzo—*UNRELATED*: *Employment*: University of Florence. Paolo Perrini—*UNRELATED*: *Employment*: University of Pisa, *Comments*: I am an associate professor of neuroradiology. Vincent Costalat—*UNRELATED*: *Grants/Grants Pending*: Medtronic, Stryker*; *Payment for Development of Educational Presentations*: Medtronic, Stryker, Balt, MicroVention. Alain Bonafe—*UNRELATED*: *Employment*: Hopital Gui de Chauliac service de neuroradiology. Waleed Brinjikji—*UNRELATED*: *Consultancy*: Johnson and Johnson, *Comments*: $500 consulting fee; *Patents (Planned, Pending or Issued)*: intellectual property in balloon catheter technology; *Stock/Stock Options*: Superior Medical Editing stock options; *Travel/Accommodations/Meeting Expenses Unrelated to Activities Listed*: Johnson and Johnson; *Other*: CEO of Marblehead Medical LLC. Carlos Riquelme—*UNRELATED*: *Employment*: Hopital Gui de Chauliac service de neuroradiology. *Money paid to institution.

## References

1.  1. Adeeb N, Griessenauer CJ, Shallwani H, et al. Pipeline embolization device in treatment of 50 unruptured large and giant aneurysms. World Neurosurg 2017;105:232–37 doi:10.1016/j.wneu.2017.05.128 pmid:28578117
    
    [CrossRef](http://www.ajnr.org/lookup/external-ref?access_num=10.1016/j.wneu.2017.05.128&link_type=DOI) 
    
    [PubMed](http://www.ajnr.org/lookup/external-ref?access_num=28578117&link_type=MED&atom=%2Fajnr%2F39%2F5%2F852.atom) 

2.  2. Gruber A, Killer M, Bavinzski G, et al. Clinical and angiographic results of endosaccular coiling treatment of giant and very large intracranial aneurysms: a 7-year, single-center experience. Neurosurgery 1999;45:793–803; discussion 803–04 doi:10.1097/00006123-199910000-00013 pmid:10515473
    
    [CrossRef](http://www.ajnr.org/lookup/external-ref?access_num=10.1097/00006123-199910000-00013&link_type=DOI) 
    
    [PubMed](http://www.ajnr.org/lookup/external-ref?access_num=10515473&link_type=MED&atom=%2Fajnr%2F39%2F5%2F852.atom) 
    
    [Web of Science](http://www.ajnr.org/lookup/external-ref?access_num=000082932700029&link_type=ISI) 

3.  3. Gao X, Liang G, Li Z, et al. A single-centre experience and follow-up of patients with endovascular coiling of large and giant intracranial aneurysms with parent artery preservation. J Clin Neurosci 2012;19:364–69 doi:10.1016/j.jocn.2011.03.038 pmid:22277568
    
    [CrossRef](http://www.ajnr.org/lookup/external-ref?access_num=10.1016/j.jocn.2011.03.038&link_type=DOI) 
    
    [PubMed](http://www.ajnr.org/lookup/external-ref?access_num=22277568&link_type=MED&atom=%2Fajnr%2F39%2F5%2F852.atom) 

4.  4. Clarençon F, Bonneville F, Boch AL, et al. Parent artery occlusion is not obsolete in giant aneurysms of the ICA: experience with very-long-term follow-up. Neuroradiology 2011;53:973–82 doi:10.1007/s00234-010-0800-8 pmid:21152912
    
    [CrossRef](http://www.ajnr.org/lookup/external-ref?access_num=10.1007/s00234-010-0800-8&link_type=DOI) 
    
    [PubMed](http://www.ajnr.org/lookup/external-ref?access_num=21152912&link_type=MED&atom=%2Fajnr%2F39%2F5%2F852.atom) 
    
    [Web of Science](http://www.ajnr.org/lookup/external-ref?access_num=000297162600006&link_type=ISI) 

5.  5. Jahromi BS, Mocco J, Bang JA, et al. Clinical and angiographic outcome after endovascular management of giant intracranial aneurysms. Neurosurgery 2008;63:662–74; discussion 674–75 doi:10.1227/01.NEU.0000325497.79690.4C pmid:18981877
    
    [CrossRef](http://www.ajnr.org/lookup/external-ref?access_num=10.1227/01.NEU.0000325497.79690.4C&link_type=DOI) 
    
    [PubMed](http://www.ajnr.org/lookup/external-ref?access_num=18981877&link_type=MED&atom=%2Fajnr%2F39%2F5%2F852.atom) 
    
    [Web of Science](http://www.ajnr.org/lookup/external-ref?access_num=000260578600018&link_type=ISI) 

6.  6. Biondi A, Jean B, Vivas E, et al. Giant and large peripheral cerebral aneurysms: etiopathologic considerations, endovascular treatment, and long-term follow-up. AJNR Am J Neuroradiol 2006;27:1685–92 pmid:16971615
    
    [Abstract/FREE Full Text](http://www.ajnr.org/lookup/ijlink/YTozOntzOjQ6InBhdGgiO3M6MTQ6Ii9sb29rdXAvaWpsaW5rIjtzOjU6InF1ZXJ5IjthOjQ6e3M6ODoibGlua1R5cGUiO3M6NDoiQUJTVCI7czoxMToiam91cm5hbENvZGUiO3M6NDoiYWpuciI7czo1OiJyZXNpZCI7czo5OiIyNy84LzE2ODUiO3M6NDoiYXRvbSI7czoxOToiL2FqbnIvMzkvNS84NTIuYXRvbSI7fXM6ODoiZnJhZ21lbnQiO3M6MDoiIjt9) 

7.  7. van Rooij WJ, Sluzewski M. Endovascular treatment of large and giant aneurysms. AJNR Am J Neuroradiol 2009;30:12–18 pmid:18719032
    
    [Abstract/FREE Full Text](http://www.ajnr.org/lookup/ijlink/YTozOntzOjQ6InBhdGgiO3M6MTQ6Ii9sb29rdXAvaWpsaW5rIjtzOjU6InF1ZXJ5IjthOjQ6e3M6ODoibGlua1R5cGUiO3M6NDoiQUJTVCI7czoxMToiam91cm5hbENvZGUiO3M6NDoiYWpuciI7czo1OiJyZXNpZCI7czo3OiIzMC8xLzEyIjtzOjQ6ImF0b20iO3M6MTk6Ii9ham5yLzM5LzUvODUyLmF0b20iO31zOjg6ImZyYWdtZW50IjtzOjA6IiI7fQ==) 

8.  8. Moher D, Liberati A, Tetzlaff J, et al. Preferred reporting items for systematic reviews and meta-analyses: the PRISMA statement. Int J Surg 2010;8:336–41 doi:10.1016/j.ijsu.2010.02.007 pmid:20171303
    
    [CrossRef](http://www.ajnr.org/lookup/external-ref?access_num=10.1016/j.ijsu.2010.02.007&link_type=DOI) 
    
    [PubMed](http://www.ajnr.org/lookup/external-ref?access_num=20171303&link_type=MED&atom=%2Fajnr%2F39%2F5%2F852.atom) 

9.  9. Wells G SB, O'Connell D. The Newcastle-Ottawa Scale (NOS) for assessing the quality of nonradomized studies in meta-analyses. Ottawa: Ottawal Hospital Research Institute; 2011 [http://www.evidencebasedpublichealth.de/download/Newcastle\_Ottowa\_Scale\_Pope\_Bruce.pdfzurlx](http://www.evidencebasedpublichealth.de/download/Newcastle\_Ottowa_Scale_Pope_Bruce.pdfzurlx). Accessed September 5, 2017
    
    

10. 10. Peschillo S, Caporlingua A, Resta MC, et al. Endovascular treatment of large and giant carotid aneurysms with flow-diverter stents alone or in combination with coils: a multicenter experience and long-term follow-up. Oper Neurosurg (Hagerstown) 2017;13:492-502 doi:10.1093/ons/opx032 pmid:28838114
    
    [CrossRef](http://www.ajnr.org/lookup/external-ref?access_num=10.1093/ons/opx032&link_type=DOI) 
    
    [PubMed](http://www.ajnr.org/lookup/external-ref?access_num=28838114&link_type=MED&atom=%2Fajnr%2F39%2F5%2F852.atom) 

11. 11. Yang H, Liu JX, Zhou ZP, et al. Comparison of the tumor-forming rate between the SCID and NOD/SCID mice used to set up acute myeloid leukemia model [in Chinese]. Zhongguo Shi Yan Xue Ye Xue Za Zhi 2015;23:328–34 doi:10.7534/j.issn.1009-2137.2015.02.007 pmid:25948180
    
    [CrossRef](http://www.ajnr.org/lookup/external-ref?access_num=10.7534/j.issn.1009-2137.2015.02.007&link_type=DOI) 
    
    [PubMed](http://www.ajnr.org/lookup/external-ref?access_num=25948180&link_type=MED&atom=%2Fajnr%2F39%2F5%2F852.atom) 

12. 12. Lin N, Brouillard AM, Krishna C, et al. Use of coils in conjunction with the Pipeline embolization device for treatment of intracranial aneurysms. Neurosurgery 2015;76:142–49 doi:10.1227/NEU.0000000000000579 pmid:25255261
    
    [CrossRef](http://www.ajnr.org/lookup/external-ref?access_num=10.1227/NEU.0000000000000579&link_type=DOI) 
    
    [PubMed](http://www.ajnr.org/lookup/external-ref?access_num=25255261&link_type=MED&atom=%2Fajnr%2F39%2F5%2F852.atom) 

13. 13. Kallmes DF, Hanel R, Lopes D, et al. International retrospective study of the Pipeline embolization device: a multicenter aneurysm treatment study. AJNR Am J Neuroradiol 2015;36:108–15 doi:10.3174/ajnr.A4111 pmid:25355814
    
    [Abstract/FREE Full Text](http://www.ajnr.org/lookup/ijlink/YTozOntzOjQ6InBhdGgiO3M6MTQ6Ii9sb29rdXAvaWpsaW5rIjtzOjU6InF1ZXJ5IjthOjQ6e3M6ODoibGlua1R5cGUiO3M6NDoiQUJTVCI7czoxMToiam91cm5hbENvZGUiO3M6NDoiYWpuciI7czo1OiJyZXNpZCI7czo4OiIzNi8xLzEwOCI7czo0OiJhdG9tIjtzOjE5OiIvYWpuci8zOS81Lzg1Mi5hdG9tIjt9czo4OiJmcmFnbWVudCI7czowOiIiO30=) 

14. 14. Hassan T, Hamimi A. Successful endovascular management of brain aneurysms presenting with mass effect and cranial nerve palsy. Neurosurg Rev 2013;36:87–97; discussion 97 doi:10.1007/s10143-012-0404-3 pmid:22782498
    
    [CrossRef](http://www.ajnr.org/lookup/external-ref?access_num=10.1007/s10143-012-0404-3&link_type=DOI) 
    
    [PubMed](http://www.ajnr.org/lookup/external-ref?access_num=22782498&link_type=MED&atom=%2Fajnr%2F39%2F5%2F852.atom) 

15. 15. Saatci I, Yavuz K, Ozer C, et al. 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 doi:10.3174/ajnr.A3246 pmid:22821921
    
    [Abstract/FREE Full Text](http://www.ajnr.org/lookup/ijlink/YTozOntzOjQ6InBhdGgiO3M6MTQ6Ii9sb29rdXAvaWpsaW5rIjtzOjU6InF1ZXJ5IjthOjQ6e3M6ODoibGlua1R5cGUiO3M6NDoiQUJTVCI7czoxMToiam91cm5hbENvZGUiO3M6NDoiYWpuciI7czo1OiJyZXNpZCI7czo5OiIzMy84LzE0MzYiO3M6NDoiYXRvbSI7czoxOToiL2FqbnIvMzkvNS84NTIuYXRvbSI7fXM6ODoiZnJhZ21lbnQiO3M6MDoiIjt9) 

16. 16. Strauss I, Maimon S. Silk flow diverter in the treatment of complex intracranial aneurysms: a single-center experience with 60 patients. Acta Neurochir (Wien) 2016;158:247–54 doi:10.1007/s00701-015-2644-9 pmid:26630988
    
    [CrossRef](http://www.ajnr.org/lookup/external-ref?access_num=10.1007/s00701-015-2644-9&link_type=DOI) 
    
    [PubMed](http://www.ajnr.org/lookup/external-ref?access_num=26630988&link_type=MED&atom=%2Fajnr%2F39%2F5%2F852.atom) 

17. 17. van Oel LI, van Rooij WJ, Sluzewski M, et al. Reconstructive endovascular treatment of fusiform and dissecting basilar trunk aneurysms with flow diverters, stents, and coils. AJNR Am J Neuroradiol 2013;34:589–95 doi:10.3174/ajnr.A3255 pmid:22918431
    
    [Abstract/FREE Full Text](http://www.ajnr.org/lookup/ijlink/YTozOntzOjQ6InBhdGgiO3M6MTQ6Ii9sb29rdXAvaWpsaW5rIjtzOjU6InF1ZXJ5IjthOjQ6e3M6ODoibGlua1R5cGUiO3M6NDoiQUJTVCI7czoxMToiam91cm5hbENvZGUiO3M6NDoiYWpuciI7czo1OiJyZXNpZCI7czo4OiIzNC8zLzU4OSI7czo0OiJhdG9tIjtzOjE5OiIvYWpuci8zOS81Lzg1Mi5hdG9tIjt9czo4OiJmcmFnbWVudCI7czowOiIiO30=) 

18. 18. Szikora I, Turányi E, Marosfoi M. Evolution of flow-diverter endothelialization and thrombus organization in giant fusiform aneurysms after flow diversion: a histopathologic study. AJNR Am J Neuroradiol 2015;36:1716–20 doi:10.3174/ajnr.A4336 pmid:26251428
    
    [Abstract/FREE Full Text](http://www.ajnr.org/lookup/ijlink/YTozOntzOjQ6InBhdGgiO3M6MTQ6Ii9sb29rdXAvaWpsaW5rIjtzOjU6InF1ZXJ5IjthOjQ6e3M6ODoibGlua1R5cGUiO3M6NDoiQUJTVCI7czoxMToiam91cm5hbENvZGUiO3M6NDoiYWpuciI7czo1OiJyZXNpZCI7czo5OiIzNi85LzE3MTYiO3M6NDoiYXRvbSI7czoxOToiL2FqbnIvMzkvNS84NTIuYXRvbSI7fXM6ODoiZnJhZ21lbnQiO3M6MDoiIjt9) 

19. 19. Rouchaud A, Ramana C, Brinjikji W, et al. Wall apposition is a key factor for aneurysm occlusion after flow diversion: a histologic evaluation in 41 rabbits. AJNR Am J Neuroradiol 2016;37:2087–91 doi:10.3174/ajnr.A4848 pmid:27390319
    
    [Abstract/FREE Full Text](http://www.ajnr.org/lookup/ijlink/YTozOntzOjQ6InBhdGgiO3M6MTQ6Ii9sb29rdXAvaWpsaW5rIjtzOjU6InF1ZXJ5IjthOjQ6e3M6ODoibGlua1R5cGUiO3M6NDoiQUJTVCI7czoxMToiam91cm5hbENvZGUiO3M6NDoiYWpuciI7czo1OiJyZXNpZCI7czoxMDoiMzcvMTEvMjA4NyI7czo0OiJhdG9tIjtzOjE5OiIvYWpuci8zOS81Lzg1Mi5hdG9tIjt9czo4OiJmcmFnbWVudCI7czowOiIiO30=) 

20. 20. Rouchaud A, Brinjikji W, Lanzino G, et al. Delayed hemorrhagic complications after flow diversion for intracranial aneurysms: a literature overview. Neuroradiology 2016;58:171–77 doi:10.1007/s00234-015-1615-4 pmid:26553302
    
    [CrossRef](http://www.ajnr.org/lookup/external-ref?access_num=10.1007/s00234-015-1615-4&link_type=DOI) 
    
    [PubMed](http://www.ajnr.org/lookup/external-ref?access_num=26553302&link_type=MED&atom=%2Fajnr%2F39%2F5%2F852.atom) 

21. 21. Lubicz B, Leclerc X, Gauvrit JY, et al. Giant vertebrobasilar aneurysms: endovascular treatment and long-term follow-up. Neurosurgery 2004;55:316–23; discussion 323–26 doi:10.1227/01.NEU.0000129477.15636.AE pmid:15271237
    
    [CrossRef](http://www.ajnr.org/lookup/external-ref?access_num=10.1227/01.NEU.0000129477.15636.AE&link_type=DOI) 
    
    [PubMed](http://www.ajnr.org/lookup/external-ref?access_num=15271237&link_type=MED&atom=%2Fajnr%2F39%2F5%2F852.atom) 
    
    [Web of Science](http://www.ajnr.org/lookup/external-ref?access_num=000223191500010&link_type=ISI) 

22. 22. Sluzewski M, Brilstra EH, van Rooij WJ, et al. Bilateral vertebral artery balloon occlusion for giant vertebrobasilar aneurysms. Neuroradiology 2001;43:336–41 doi:10.1007/s002340000498 pmid:11338421
    
    [CrossRef](http://www.ajnr.org/lookup/external-ref?access_num=10.1007/s002340000498&link_type=DOI) 
    
    [PubMed](http://www.ajnr.org/lookup/external-ref?access_num=11338421&link_type=MED&atom=%2Fajnr%2F39%2F5%2F852.atom) 
    
    [Web of Science](http://www.ajnr.org/lookup/external-ref?access_num=000168117600015&link_type=ISI) 

23. 23. John S, Bain MD, Hussain MS, et al. Long-term effect of flow diversion on large and giant aneurysms: MRI-DSA clinical correlation study. World Neurosurg 2016;93:60–66 doi:10.1016/j.wneu.2016.05.082 pmid:27268315
    
    [CrossRef](http://www.ajnr.org/lookup/external-ref?access_num=10.1016/j.wneu.2016.05.082&link_type=DOI) 
    
    [PubMed](http://www.ajnr.org/lookup/external-ref?access_num=27268315&link_type=MED&atom=%2Fajnr%2F39%2F5%2F852.atom) 

24. 24. Johnson AK, Munich SA, Tan LA, et al. Complication analysis in nitinol stent-assisted embolization of 486 intracranial aneurysms. J Neurosurg 2015;123:453–59 doi:10.3171/2014.10.JNS141361 pmid:25978711
    
    [CrossRef](http://www.ajnr.org/lookup/external-ref?access_num=10.3171/2014.10.JNS141361&link_type=DOI) 
    
    [PubMed](http://www.ajnr.org/lookup/external-ref?access_num=25978711&link_type=MED&atom=%2Fajnr%2F39%2F5%2F852.atom) 

25. 25. Zhang Z, Lv X, Yang X, et al. Endovascular management of giant aneurysms: an introspection. Neurol India 2015;63:184–89 doi:10.4103/0028-3886.156278 pmid:25947981
    
    [CrossRef](http://www.ajnr.org/lookup/external-ref?access_num=10.4103/0028-3886.156278&link_type=DOI) 
    
    [PubMed](http://www.ajnr.org/lookup/external-ref?access_num=25947981&link_type=MED&atom=%2Fajnr%2F39%2F5%2F852.atom) 

26. 26. Labeyrie MA, Lenck S, Bresson D, et al. Parent artery occlusion in large, giant, or fusiform aneurysms of the carotid siphon: clinical and imaging results. AJNR Am J Neuroradiol 2015;36:140–45 doi:10.3174/ajnr.A4064 pmid:25082818
    
    [Abstract/FREE Full Text](http://www.ajnr.org/lookup/ijlink/YTozOntzOjQ6InBhdGgiO3M6MTQ6Ii9sb29rdXAvaWpsaW5rIjtzOjU6InF1ZXJ5IjthOjQ6e3M6ODoibGlua1R5cGUiO3M6NDoiQUJTVCI7czoxMToiam91cm5hbENvZGUiO3M6NDoiYWpuciI7czo1OiJyZXNpZCI7czo4OiIzNi8xLzE0MCI7czo0OiJhdG9tIjtzOjE5OiIvYWpuci8zOS81Lzg1Mi5hdG9tIjt9czo4OiJmcmFnbWVudCI7czowOiIiO30=) 

27. 27. Wang B, Gao BL, Xu GP, et al. Endovascular embolization is applicable for large and giant intracranial aneurysms: experience in one center with long-term angiographic follow-up. Acta Radiol 2015;56:105–13 doi:10.1177/0284185113520312 pmid:24518686
    
    [CrossRef](http://www.ajnr.org/lookup/external-ref?access_num=10.1177/0284185113520312&link_type=DOI) 
    
    [PubMed](http://www.ajnr.org/lookup/external-ref?access_num=24518686&link_type=MED&atom=%2Fajnr%2F39%2F5%2F852.atom) 

28. 28. Dumont TM, Levy EI, Siddiqui AH, et al. Endovascular treatment of giant intracranial aneurysms: a work in progress. World Neurosurg 2014;81:671–75 doi:10.1016/j.wneu.2013.01.102 pmid:23376376
    
    [CrossRef](http://www.ajnr.org/lookup/external-ref?access_num=10.1016/j.wneu.2013.01.102&link_type=DOI) 
    
    [PubMed](http://www.ajnr.org/lookup/external-ref?access_num=23376376&link_type=MED&atom=%2Fajnr%2F39%2F5%2F852.atom) 

29. 29. Derrey S, Penchet G, Thines L, et al. French collaborative group series on giant intracranial aneurysms: current management. Neurochirurgie 2015;61:371–77 doi:10.1016/j.neuchi.2013.11.006 pmid:24647149
    
    [CrossRef](http://www.ajnr.org/lookup/external-ref?access_num=10.1016/j.neuchi.2013.11.006&link_type=DOI) 
    
    [PubMed](http://www.ajnr.org/lookup/external-ref?access_num=24647149&link_type=MED&atom=%2Fajnr%2F39%2F5%2F852.atom) 

30. 30. Cinar C, Bozkaya H, Oran I. Endovascular treatment of cranial aneurysms with the Pipeline flow-diverting stent: preliminary mid-term results. Diagn Interv Radiol 2013;19:154–64 doi:10.4261/1305-3825.DIR.6111-12.1 pmid:23233405
    
    [CrossRef](http://www.ajnr.org/lookup/external-ref?access_num=10.4261/1305-3825.DIR.6111-12.1&link_type=DOI) 
    
    [PubMed](http://www.ajnr.org/lookup/external-ref?access_num=23233405&link_type=MED&atom=%2Fajnr%2F39%2F5%2F852.atom) 

31. 31. Yu SC, Kwok CK, Cheng PW, et al. Intracranial aneurysms: midterm outcome of Pipeline embolization device—a prospective study in 143 patients with 178 aneurysms. Radiology 2012;265:893–901 doi:10.1148/radiol.12120422 pmid:22996749
    
    [CrossRef](http://www.ajnr.org/lookup/external-ref?access_num=10.1148/radiol.12120422&link_type=DOI) 
    
    [PubMed](http://www.ajnr.org/lookup/external-ref?access_num=22996749&link_type=MED&atom=%2Fajnr%2F39%2F5%2F852.atom) 
    
    [Web of Science](http://www.ajnr.org/lookup/external-ref?access_num=000311420300027&link_type=ISI) 

32. 32. Limaye US, Baheti A, Saraf R, et al. Endovascular management of giant intracranial aneurysms of the posterior circulation. Neurol India 2012;60:597–603 doi:10.4103/0028-3886.105193 pmid:23287321
    
    [CrossRef](http://www.ajnr.org/lookup/external-ref?access_num=10.4103/0028-3886.105193&link_type=DOI) 
    
    [PubMed](http://www.ajnr.org/lookup/external-ref?access_num=23287321&link_type=MED&atom=%2Fajnr%2F39%2F5%2F852.atom) 

33. 33. Matouk CC, Kaderali Z, terBrugge KG, et al. Long-term clinical and imaging follow-up of complex intracranial aneurysms treated by endovascular parent vessel occlusion. AJNR Am J Neuroradiol 2012;33:1991–97 doi:10.3174/ajnr.A3079 pmid:22555575
    
    [Abstract/FREE Full Text](http://www.ajnr.org/lookup/ijlink/YTozOntzOjQ6InBhdGgiO3M6MTQ6Ii9sb29rdXAvaWpsaW5rIjtzOjU6InF1ZXJ5IjthOjQ6e3M6ODoibGlua1R5cGUiO3M6NDoiQUJTVCI7czoxMToiam91cm5hbENvZGUiO3M6NDoiYWpuciI7czo1OiJyZXNpZCI7czoxMDoiMzMvMTAvMTk5MSI7czo0OiJhdG9tIjtzOjE5OiIvYWpuci8zOS81Lzg1Mi5hdG9tIjt9czo4OiJmcmFnbWVudCI7czowOiIiO30=) 

34. 34. Hauck EF, Welch BG, White JA, et al. Stent/coil treatment of very large and giant unruptured ophthalmic and cavernous aneurysms. Surg Neurol 2009;71:19–24; discussion 24 doi:10.1016/j.surneu.2008.01.025 pmid:18423540
    
    [CrossRef](http://www.ajnr.org/lookup/external-ref?access_num=10.1016/j.surneu.2008.01.025&link_type=DOI) 
    
    [PubMed](http://www.ajnr.org/lookup/external-ref?access_num=18423540&link_type=MED&atom=%2Fajnr%2F39%2F5%2F852.atom) 
    
    [Web of Science](http://www.ajnr.org/lookup/external-ref?access_num=000262098400004&link_type=ISI) 

35. 35. Lv X, Jiang C, Li Y, et al. Treatment of giant intracranial aneurysms. Interv Neuroradiol 2009;15:135–44 doi:10.1177/159101990901500201 pmid:20465907
    
    [CrossRef](http://www.ajnr.org/lookup/external-ref?access_num=10.1177/159101990901500201&link_type=DOI) 
    
    [PubMed](http://www.ajnr.org/lookup/external-ref?access_num=20465907&link_type=MED&atom=%2Fajnr%2F39%2F5%2F852.atom) 

36. 36. Suzuki S, Tateshima S, Jahan R, et al. Endovascular treatment of middle cerebral artery aneurysms with detachable coils: angiographic and clinical outcomes in 115 consecutive patients. Neurosurgery 2009;64:876–88; discussion 888–89 doi:10.1227/01.NEU.0000343534.05655.37 pmid:19287326
    
    [CrossRef](http://www.ajnr.org/lookup/external-ref?access_num=10.1227/01.NEU.0000343534.05655.37&link_type=DOI) 
    
    [PubMed](http://www.ajnr.org/lookup/external-ref?access_num=19287326&link_type=MED&atom=%2Fajnr%2F39%2F5%2F852.atom) 
    
    [Web of Science](http://www.ajnr.org/lookup/external-ref?access_num=000265661100030&link_type=ISI) 

37. 37. Standhardt H, Boecher-Schwarz H, Gruber A, et al. 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 doi:10.1161/STROKEAHA.107.496372 pmid:18258836
    
    [Abstract/FREE Full Text](http://www.ajnr.org/lookup/ijlink/YTozOntzOjQ6InBhdGgiO3M6MTQ6Ii9sb29rdXAvaWpsaW5rIjtzOjU6InF1ZXJ5IjthOjQ6e3M6ODoibGlua1R5cGUiO3M6NDoiQUJTVCI7czoxMToiam91cm5hbENvZGUiO3M6OToic3Ryb2tlYWhhIjtzOjU6InJlc2lkIjtzOjg6IjM5LzMvODk5IjtzOjQ6ImF0b20iO3M6MTk6Ii9ham5yLzM5LzUvODUyLmF0b20iO31zOjg6ImZyYWdtZW50IjtzOjA6IiI7fQ==) 

38. 38. Li MH, Li YD, Fang C, et al. Endovascular treatment of giant or very large intracranial aneurysms with different modalities: an analysis of 20 cases. Neuroradiology 2007;49:819–28 doi:10.1007/s00234-007-0257-6 pmid:17611747
    
    [CrossRef](http://www.ajnr.org/lookup/external-ref?access_num=10.1007/s00234-007-0257-6&link_type=DOI) 
    
    [PubMed](http://www.ajnr.org/lookup/external-ref?access_num=17611747&link_type=MED&atom=%2Fajnr%2F39%2F5%2F852.atom) 
    
    [Web of Science](http://www.ajnr.org/lookup/external-ref?access_num=000249794400005&link_type=ISI) 

39. 39. Suzuki S, Kurata A, Kan S, et al. Efficacy of endovascular surgery for unruptured internal carotid artery aneurysms presenting with cranial nerve symptoms. Interv Neuroradiol 2007;13(Suppl 1):163–69 doi:10.1177/15910199070130S125 pmid:20566096
    
    [CrossRef](http://www.ajnr.org/lookup/external-ref?access_num=10.1177/15910199070130S125&link_type=DOI) 
    
    [PubMed](http://www.ajnr.org/lookup/external-ref?access_num=20566096&link_type=MED&atom=%2Fajnr%2F39%2F5%2F852.atom) 

40. 40. Deshaies EM, Adamo MA, Boulos AS. A prospective single-center analysis of the safety and efficacy of the Hydrocoil embolization system for the treatment of intracranial aneurysms. J Neurosurg 2007;106:226–33 doi:10.3171/jns.2007.106.2.226 pmid:17410704
    
    [CrossRef](http://www.ajnr.org/lookup/external-ref?access_num=10.3171/jns.2007.106.2.226&link_type=DOI) 
    
    [PubMed](http://www.ajnr.org/lookup/external-ref?access_num=17410704&link_type=MED&atom=%2Fajnr%2F39%2F5%2F852.atom) 
    
    [Web of Science](http://www.ajnr.org/lookup/external-ref?access_num=000244519700006&link_type=ISI) 

41. 41. Heran NS, Song JK, Kupersmith MJ, et al. Large ophthalmic segment aneurysms with anterior optic pathway compression: assessment of anatomical and visual outcomes after endosaccular coil therapy. J Neurosurg 2007;106:968–75 doi:10.3171/jns.2007.106.6.968 pmid:17564166
    
    [CrossRef](http://www.ajnr.org/lookup/external-ref?access_num=10.3171/jns.2007.106.6.968&link_type=DOI) 
    
    [PubMed](http://www.ajnr.org/lookup/external-ref?access_num=17564166&link_type=MED&atom=%2Fajnr%2F39%2F5%2F852.atom) 
    
    [Web of Science](http://www.ajnr.org/lookup/external-ref?access_num=000246894900006&link_type=ISI) 

42. 42. Cekirge HS, Saatci I, Ozturk MH, et al. Late angiographic and clinical follow-up results of 100 consecutive aneurysms treated with Onyx reconstruction: largest single-center experience. Neuroradiology 2006;48:113–26 doi:10.1007/s00234-005-0007-6 pmid:16391915
    
    [CrossRef](http://www.ajnr.org/lookup/external-ref?access_num=10.1007/s00234-005-0007-6&link_type=DOI) 
    
    [PubMed](http://www.ajnr.org/lookup/external-ref?access_num=16391915&link_type=MED&atom=%2Fajnr%2F39%2F5%2F852.atom) 
    
    [Web of Science](http://www.ajnr.org/lookup/external-ref?access_num=000235219100006&link_type=ISI) 

43. 43. Murayama Y, Nien YL, Duckwiler G, et al. Guglielmi detachable coil embolization of cerebral aneurysms: 11 years' experience. J Neurosurg 2003;98:959–66 doi:10.3171/jns.2003.98.5.0959 pmid:12744354
    
    [CrossRef](http://www.ajnr.org/lookup/external-ref?access_num=10.3171/jns.2003.98.5.0959&link_type=DOI) 
    
    [PubMed](http://www.ajnr.org/lookup/external-ref?access_num=12744354&link_type=MED&atom=%2Fajnr%2F39%2F5%2F852.atom) 
    
    [Web of Science](http://www.ajnr.org/lookup/external-ref?access_num=000182619000010&link_type=ISI) 

44. 44. Sluzewski M, Menovsky T, van Rooij WJ, et al. Coiling of very large or giant cerebral aneurysms: long-term clinical and serial angiographic results. AJNR Am J Neuroradiol 2003;24:257–62 pmid:12591644
    
    [Abstract/FREE Full Text](http://www.ajnr.org/lookup/ijlink/YTozOntzOjQ6InBhdGgiO3M6MTQ6Ii9sb29rdXAvaWpsaW5rIjtzOjU6InF1ZXJ5IjthOjQ6e3M6ODoibGlua1R5cGUiO3M6NDoiQUJTVCI7czoxMToiam91cm5hbENvZGUiO3M6NDoiYWpuciI7czo1OiJyZXNpZCI7czo4OiIyNC8yLzI1NyI7czo0OiJhdG9tIjtzOjE5OiIvYWpuci8zOS81Lzg1Mi5hdG9tIjt9czo4OiJmcmFnbWVudCI7czowOiIiO30=) 

45. 45. Ross IB, Weill A, Piotin M, et al. Endovascular treatment of distally located giant aneurysms. Neurosurgery 2000;47:1147–52; discussion 1152–53 doi:10.1097/00006123-200011000-00025 pmid:11063108
    
    [CrossRef](http://www.ajnr.org/lookup/external-ref?access_num=10.1097/00006123-200011000-00025&link_type=DOI) 
    
    [PubMed](http://www.ajnr.org/lookup/external-ref?access_num=11063108&link_type=MED&atom=%2Fajnr%2F39%2F5%2F852.atom) 
    
    [Web of Science](http://www.ajnr.org/lookup/external-ref?access_num=000090144400061&link_type=ISI) 

46. 46. Kim SJ, Choi IS. Midterm outcome of partially thrombosed intracranial aneurysms treated with Guglielmi detachable coils. Interv Neuroradiol 2000;6:13–25 doi:10.1177/159101990000600103 pmid:20667178
    
    [CrossRef](http://www.ajnr.org/lookup/external-ref?access_num=10.1177/159101990000600103&link_type=DOI) 
    
    [PubMed](http://www.ajnr.org/lookup/external-ref?access_num=20667178&link_type=MED&atom=%2Fajnr%2F39%2F5%2F852.atom) 

47. 47. Tateshima S, Murayama Y, Gobin YP, et al. Endovascular treatment of basilar tip aneurysms using Guglielmi detachable coils: anatomic and clinical outcomes in 73 patients from a single institution. Neurosurgery 2000;47:1332–39; discussion 1339–42 pmid:11126904
    
    [CrossRef](http://www.ajnr.org/lookup/external-ref?access_num=10.1097/00006123-200012000-00012&link_type=DOI) 
    
    [PubMed](http://www.ajnr.org/lookup/external-ref?access_num=11126904&link_type=MED&atom=%2Fajnr%2F39%2F5%2F852.atom) 
    
    [Web of Science](http://www.ajnr.org/lookup/external-ref?access_num=000165569900030&link_type=ISI) 

48. 48. Morishima H, Kurata A, Ohmomo T, et al. The efficacy of endovascular surgery for treatment of giant aneurysms with special reference to coil embolization for endosaccular occlusion. Interv Neuroradiol 1998;4(Suppl 1):135–43 doi:10.1177/15910199980040S129 pmid:20673462
    
    [CrossRef](http://www.ajnr.org/lookup/external-ref?access_num=10.1177/15910199980040S129&link_type=DOI) 
    
    [PubMed](http://www.ajnr.org/lookup/external-ref?access_num=20673462&link_type=MED&atom=%2Fajnr%2F39%2F5%2F852.atom) 

49. 49. Viñuela F, Duckwiler G, Mawad M. Guglielmi detachable coil embolization of acute intracranial aneurysm: perioperative anatomical and clinical outcome in 403 patients. J Neurosurg 1997;86:475–82 doi:10.3171/jns.1997.86.3.0475 pmid:9046305
    
    [CrossRef](http://www.ajnr.org/lookup/external-ref?access_num=10.3171/jns.1997.86.3.0475&link_type=DOI) 
    
    [PubMed](http://www.ajnr.org/lookup/external-ref?access_num=9046305&link_type=MED&atom=%2Fajnr%2F39%2F5%2F852.atom) 
    
    [Web of Science](http://www.ajnr.org/lookup/external-ref?access_num=A1997WJ26700008&link_type=ISI) 

50. 50. Guglielmi G, Viñuela F, Duckwiler G, et al. Endovascular treatment of posterior circulation aneurysms by electrothrombosis using electrically detachable coils. J Neurosurg 1992;77:515–24 doi:10.3171/jns.1992.77.4.0515 pmid:1527608
    
    [CrossRef](http://www.ajnr.org/lookup/external-ref?access_num=10.3171/jns.1992.77.4.0515&link_type=DOI) 
    
    [PubMed](http://www.ajnr.org/lookup/external-ref?access_num=1527608&link_type=MED&atom=%2Fajnr%2F39%2F5%2F852.atom) 
    
    [Web of Science](http://www.ajnr.org/lookup/external-ref?access_num=A1992JP64800004&link_type=ISI) 

*   Received October 13, 2017.
*   Accepted after revision January 3, 2018.


*   © 2018 by American Journal of Neuroradiology