Treatment of intracranial aneurysms with the Enterprise stent: a multicenter registry

Contribution of whole platelet aggregometry to the endovascular management of unruptured aneurysms: an institutional experience

BACKGROUND

Stent-assisted coiling of intracranial aneurysms is an efficient alternative treatment to surgical clipping but requires prolonged antiplatelet therapy. Some patients are non-responsive to aspirin and/or clopidogrel.

OBJECTIVE

To analyze the implications of this assessment using the 'whole blood aggregometry (WBA) by impedance' technique.

MATERIALS AND METHODS

The Southwestern Tertiary Aneurysm Registry was reviewed between 2002 and 2012 for patients with unruptured aneurysms treated with stent-assisted coiling. The study population was divided into patients who were tested preoperatively for platelet responsiveness to aspirin and clopidogrel ('tested' patients) and those who were not ('non-tested'). Where necessary, tested patients received additional doses of antiplatelet drugs to achieve adequate platelet inhibition. Endpoints included the incidence of non-responsiveness, the rates of thrombotic and hemorrhagic complications, and the rates of permanent morbidity and mortality.

RESULTS

A total of 266 patients fulfilled our selection criteria: 114 non-tested patients who underwent 121 procedures, and 152 tested patients who underwent 171 procedures. The two groups did not vary significantly in patient age, gender, and aneurysms location. Aspirin non-responsiveness was detected in 3 patients (1.75%) and clopidogrel non-responsiveness in 21 patients (12.3%). Non-tested patients had an 11.6% rate of thrombotic complications with a 4.1% permanent morbidity or mortality rate versus 2.3% and 0.6% in tested patients (p=0.0013). The incidence of hemorrhagic complications was similar between the two groups.

CONCLUSIONS

Preoperative platelet inhibition testing using WBA can be useful to assess and correct antiaggregant non-responsiveness, and may reduce postoperative mortality and permanent morbidity.

Canadian Registry of LVIS Jr for Treatment of Intracranial Aneurysms (CaRLA)

INTRODUCTION

Stents reduce the rate of angiographic recurrence of intracranial aneurysms. The newest stent for intracranial use is the Low-profile Visible Intraluminal Support device (LVIS Jr).

OBJECTIVE

To assess the efficacy of the new stent in a multicenter retrospective registry.

MATERIALS AND METHOD

Centers across Canada using LVIS Jr were contacted and asked to participate in a retrospective registry of consecutive patients treated with LVIS Jr for intracranial aneurysms between January 2013 and July 2015.

RESULTS

A total of 102 patients, with saccular aneurysms in 100 patients (72 women; age range 21-78 years; mean 56.0 years; median 57.5 years) were treated with a LVIS Jr stent. The mean maximum diameter of the dome and neck of the aneurysm and dome to neck ratios were 8.3 mm±7.7 mm, 4.4 mm±1.9 mm, and 1.86±1.22, respectively. Angiographic complications arose in 23 patients, clinical complications in 9 patients, and only 3% of permanent neurological deficits occurred. Death occurred in 1 patient, unrelated to the stent. The ruptured status of the aneurysms (OR=3.29; p=0.046) and use of LVIS Jr for bailout (OR=2.54; p=0.053) showed a trend towards significant association with higher angiographic complications. At the last available follow-up, 68 class I, 20 class II, and 12 class III results were seen.

CONCLUSIONS

The LVIS Jr stent is a safe and effective device for stent-assisted coiling, with 3% permanent neurological complications. Stent-assisted coiling continues to be technically challenging in cases of ruptured aneurysms and bailout situations.

Stent-Assisted Coiling of 501 Wide-Necked Intracranial Aneurysms: A Single-Center 8-Year Experience

BACKGROUND

Stent-assisted coiling has expanded the treatment of complex wide-necked intracranial aneurysms. We present our experience with stent-assisted coiling, with an emphasis on procedure-related neurologic complications and the incidence of angiographic recurrence.

METHODS

A total of 480 patients with 501 aneurysms who were treated with stent-assisted coiling between January 2007 and December 2014 were reviewed retrospectively. Baseline characteristics, procedure-related complications, angiographic follow-up results, and clinical outcomes were statistically analyzed.

RESULTS

Among the 480 patients, 423 (88%) were treated electively and 57 (11%) were treated in the context of subarachnoid hemorrhage. There were 22 (4.58%) overall procedure-related complications, which caused death in 4 patients (0.83%) and morbidity in 4 patients (0.83%). In a logistic regression analysis, the complications differed significantly among the patients with hypertension (odds ratio [OR], 2.85; 95% confidence interval [CI], 1.09-7.48; P = 0.03), patients with aneurysms treated with coiling before stenting (OR, 3.07; 95% CI, 1.07-8.81; P = 0.04), and patients treated with multiple stents (OR, 4.96; 95% CI, 1.02-24.07; P = 0.04). Angiographic follow-up was available for 396 patients (83.4%) for a mean of 13 months. The rates of recanalization and retreatment were 13.9% and 3.5%, respectively. In a logistic analysis, larger aneurysm size and initial incomplete aneurysm occlusion were predictors of recanalization. Clinical follow-up was available for 406 patients (85.6%) for a mean of 44.8 months, and 399 patients (98.3%) achieved a Glasgow Outcome Scale score of 5.

CONCLUSIONS

Stent-assisted coiling appears to be a safe and effective option for treating complex wide-necked aneurysms. Higher complication rates are associated with coiling before stenting, use of multiple stents, and hypertension. Stent delivery before coil deployment reduces the risk of procedural complications. Larger aneurysm size and initial incomplete occlusion are associated with aneurysm recanalization.

Use of the pCONus as an adjunct to coil embolization of acutely ruptured aneurysms

Introduction

Coil embolization of ruptured aneurysms has become the standard treatment in many situations. However, certain aneurysm morphologies pose technical difficulties and may require the use of adjunctive devices.

Objective

To present our experience with the pCONus, a new neck bridging device, as an adjunct to coil embolization for acutely ruptured aneurysms and discuss the technical success, angiographic and clinical outcomes.

Methods

We conducted a retrospective review of our database of prospectively collected data to identify all patients who presented with acute subarachnoid hemorrhage that required adjunctive treatment with the pCONus in the acute stage. We searched the database between April 2011 and April 2016.

Results

21 patients were identified (13 male, 8 female) with an average age of 54.6 years (range 31–73). 8 aneurysms were located at the basilar artery tip, 7 at the anterior communicating artery, 4 at the middle cerebral artery bifurcation, 1 pericallosal, and 1 basilar fenestration. 61.8% patients achieved modified Raymond–Roy classification I or II at immediate angiography, with 75% of patients having completely occluded aneurysms or stable appearance at initial follow-up. There were no repeat aneurysmal ruptures and two device-related complications (no permanent morbidity). Four patients in our cohort died.

Conclusions

Use of the pCONus is safe and effective in patients with acutely ruptured aneurysms and carries a high rate of technical success.

Solitaire AB Stent-Assisted Coiling of Wide-Neck Micro Aneurysms

Objective

Solitaire AB stent-assisted coiling facilitates the endovascular treatment of wide-necked intracranial aneurysms. We present our experience of coiling the micro-aneurysms of wide-neck with Solitaire AB stent assisting in a single center.

Methods

Thirty-one Solitaire AB stents were used to treat via endovascular approach patients with 31 wide-neck micro aneurysms in a single center in China. Technical and clinical complications were recorded. Modified Rankin Scale was used to evaluate the patients' conditions via clinic and telephone follow-up.

Results

The mean width of aneurysm sac was 2.30±0.42 mm, and the mean diameter of aneurysm neck was 2.83±0.48 mm. Complete occlusion was achieved in 28 aneurysms (90.32%); neck remnant was seen in 3 aneurysms (9.68%). Technical and clinical complications related to the procedure were encountered in four patients (12.5%). Two patients died (6.25%). No patient had a permanent deficit.

Conclusion

Solitaire AB stent was a safe and efficiency tool in assisting coiling of micro aneurysms with wide neck, but may be not suitable for a blaster-like one. Mid- and long-term follow-up will be required to elucidate the impact of the Solitaire AB stent on recanalization rate.

Flow diverter effect of LVIS stent on cerebral aneurysm hemodynamics: a comparison with Enterprise stents and the Pipeline device

Background

The aim of this study was to quantify the effect of the new Low-profile Visualized Intraluminal Support (LVIS®D) device and the difference of fluid diverting effect compared with the Pipeline device and the Enterprise stent using computational fluid dynamics (CFD).

Methods

In this research, we simulated three aneurysms constructed from 3D digital subtraction angiography (DSA). The Enterprise, LVIS and the Pipeline device were virtually conformed to fit into the vessel lumen and placed across the aneurysm orifice. Computational fluid dynamics analysis was performed to compare the hemodynamic differences such as WSS, Velocity and Pressure among these stents.

Results

Control referred to the unstented model, the percentage of hemodynamic changes were all compared to Control. A single LVIS stent caused more wall shear stress reduction than double Enterprise stents (39.96 vs. 30.51 %) and velocity (23.13 vs. 18.64 %). Significant reduction in wall shear stress (63.88 %) and velocity (46.05 %) was observed in the double-LVIS stents. A single Pipeline showed less reduction in WSS (51.08 %) and velocity (37.87 %) compared with double-LVIS stent. The double-Pipeline stents resulted in the most reduction in WSS (72.37 %) and velocity (54.26 %). Moreover, the pressure increased with minuscule extent after stenting, compared with the unstented model.

Conclusions

This is the first study analyzing flow modifications associated with LVIS stents. We found that the LVIS stent has certain hemodynamic effects on cerebral aneurysms: a single LVIS stent caused more flow reductions than the double-Enterprise stent but less than a Pipeline device. Nevertheless, the double-LVIS stent resulted in a better flow diverting effect than a Pipeline device.

LVIS Stent Versus Enterprise Stent for the Treatment of Unruptured Intracranial Aneurysms

OBJECTIVE

This retrospective study compared clinical and angiographic outcomes between LVIS and Enterprise stents.

MATERIALS AND METHODS

From November 2014 to December 2015, total 190 patients with 208 unruptured intracranial aneurysms were coiled assisted by LVIS and Enterprise stents. Procedure-related complications, clinical outcomes, and angiographic results were analyzed retrospectively.

RESULTS

A total of 92 patients with 96 aneurysms received LVIS stents and 98 patients with 112 aneurysms were treated with Enterprise stents. Procedure-related complications occurred in 10.9% of patients (2 hemorrhagic events and 8 thromboembolic events) in the LVIS stents group whereas 16.3% (1 hemorrhage, 1 mass effect, and 14 thromboembolic events) in the Enterprise stents group. No statistical significant differences in thromboembolic (P = 0.263), hemorrhagic complications (P = 0.611), and favorable clinical outcomes (modified Rankin Scores of 0-2) (P = 0.379) were found between 2 groups. A greater initial complete or near-complete obliteration was found in the LVIS stents group compared with the Enterprise stents group (96.9% vs. 88.4%, P = 0.034). Larger aneurysm size (P = 0.048) was an independent predictor of procedure-related complications in univariate analysis.

CONCLUSIONS

Compared with Enterprise stents, LVIS stents may achieve greater complete or near-complete occlusion rate. There was no significant difference in procedural-related complications and clinical outcomes between LVIS and Enterprise stents.

Endovascular treatment of intracranial aneurysms with the LVIS device: a systematic review

OBJECTIVE

Despite promising initial results, current knowledge regarding the use of the Low-profile Visualized Intraluminal Support (LVIS) device to treat wide-necked intracranial aneurysms is still limited. Our aim is to evaluate the feasibility, efficacy, and safety of the LVIS device in stent-assisted coiling of intracranial aneurysms.

METHODS

We conducted a systematic review by searching PubMed, EMBASE, and Cochrane Library for all published studies on the treatment of intracranial aneurysms with the LVIS device up to March 2016. Feasibility was evaluated by the technical success rate during the procedure, efficacy was evaluated by the rate of complete aneurysm occlusion at follow-up angiography, and safety was assessed by procedure-related morbidity and mortality.

RESULTS

A total of nine studies were included in the analysis, including 384 patients with 390 aneurysms. The overall technical success rate was 96.8% (95% CI 94.4% to 99.1%). The aneurysmal complete occlusion rate was 54.6% (95% CI 31.8% to 77.4%) on immediate control and 84.3% (95% CI 78.9% to 89.7%) at follow-up angiography. Procedural-related morbidity and mortality were 1.4% (95% CI 0.2% to 2.6%) and 0% (95% CI 0%), respectively. The thromboembolic event rate was 4.9% (95% CI 1.9% to 7.9%) and the hemorrhagic event rate was 2.1% (95% CI 0.7% to 3.5%), with 0.9% (95% CI 0% to 1.8%) experiencing neurologic hemorrhagic complications and 1.9% (95% CI 0.5% to 3.2%) experiencing non-neurologic hemorrhagic complications.

CONCLUSIONS

Our systematic review suggests that endovascular treatment of intracranial aneurysms with the LVIS device is feasible, safe, and effective in the short term. However, the rate of thromboembolic complications is not negligible. Further prospective studies are needed to evaluate the long-term efficacy and safety of the LVIS device.

Outcomes of Stent-assisted Coil Embolization of Wide-necked Intracranial Aneurysms Using the Solitaire™ AB Neurovascular Remodeling Device

Objective

This retrospective study presents our experience with respect to the clinical and angiographic outcomes of patients treated with stent-assisted coil embolization using Solitaire™ AB stents.

Materials and Methods

From March 2011 to December 2014, 50 patients with 55 wide-necked and/or complex intracranial aneurysms were evaluated. Four patients presented with an acute subarachnoid hemorrhage. Stent deployment was performed with a standard coiling procedure in 49 aneurysms. Three patients underwent bailout stenting, 2 patients were treated by temporary stenting and one patient was treated only by stenting without coiling for dissecting aneurysm.

Results

Successful placement of the Solitaire AB stent was achieved in all the cases. Based on the postprocedural angiographic results, a Raymond 1 was obtained in 32 (59%) of 54 aneurysms, excluded by one case of dissecting aneurysm, and a Raymond 2 in 13 (24%), and a Raymond 3 in 9 (17%). There was one thromboembolic (2%) and three hemorrhagic complications (6%). However, procedure-related morbidity or mortality was not found. Annual follow-up angiographic results from the embolization were obtained in 40 (74.1%) of 54 cases. These results were represented as Raymond 1 in 27 (67.5%), class 2 in 9 (22.5%), and class 3 in 4 (10%) cases. Angiographic improvement associated with progressive thrombosis of the aneurysm was obtained in 10 aneurysms. Four aneurysms were recanalized without requiring additional treatment. In-stent stenosis was found in one aneurysm, but stent migration was not seen on follow-up angiography.

Conclusion

Stent-assisted coil embolization using the Solitaire AB stent for treating wide-necked and/or complex intracranial aneurysms was found to be safe and effective immediately post-embolization and after follow-up. Long-term follow-up will be required to identify the effect of the Solitaire AB stent on recanalization rates.

Stent-assisted coiling and balloon-assisted coiling in the management of intracranial aneurysms: A systematic review & meta-analysis

BACKGROUND

Stent-assisted coiling and balloon-assisted coiling are well-established minimally invasive techniques for treatment of intracranial aneurysms. The aim of this study was to use meta-analysis methods to compare clinical outcomes of aneurysms treated with stent-assisted coiling versus balloon-assisted coiling.

METHODS

We searched for two-arm prospective studies and retrospective studies that compared the clinical outcomes in patients that received stent-assisted or balloon-assisted aneurysm treatment. Database search was performed through May 2015. Odds ratios (OR) with 95% confidence intervals (CI) were used to compare the clinical outcomes in patients that underwent either stent-assisted or balloon-assisted coiling for intracranial aneurysms management.

RESULTS

Complete occlusion rates at the end of the coiling procedure were similar between patients that received stent-assisted and balloon-assisted aneurysm treatment (OR=0.763, 95% CI=0.47 to 1.23, P=0.270). However, complete occlusion rates were higher with stent-assisted coiling at 6months or later after the procedure (OR=1.82, 95% CI=1.21 to 2.74). The overall complication rates and retreatment rates in patients with recurrence were similar between stent-assisted and balloon-assisted aneurysm treatments.

CONCLUSION

Stent-assisted coiling achieved better complete occlusion rates of aneurysms at 6months or later after the procedure compared to balloon-assisted coiling, without being associated with a higher risk of intraprocedural complications and retreatment.

Safety of coil occlusion of the parent artery for endovascular treatment of anterior communicating artery aneurysm

Many studies lay emphasis on the clinical importance of perforating branches of the anterior communicating artery (ACoA) and report that vascular damage of the perforators from ACoA aneurysm during surgery cause subsequent postoperative amnesia. The purpose of our study was to analyze the safety of parent artery occlusion for ACoA aneurysm coiling based on the anatomical features of the ACoA complex in 13 patients with 13 ACoA aneurysms. All patients underwent coiling of the aneurysm sac and ACoA. Aneurysm characteristics including size, dome-to-neck ratio, anterior/posterior orientation of the aneurysm dome with respect to the axis of the pericallosal artery, location of the aneurysm neck with respect to the A1-A2 segment of the anterior cerebral artery (ACA) or the ACoA, and the presence of hypoplasia/aplasia of A1 segment were assessed. The aneurysm neck was located directly on the ACoA in five aneurysms (38%), whereas eight (62%) had the neck located at the A1-A2 junction. Of the five patients whose aneurysm neck was located in the ACoA, four patients had infarcts in the basal forebrain. Three of the patients complained of amnesia. None of the aneurysms with the neck located at the A1-A2 junction were associated with infarction. There has been little evidence thus far that parent vessel occlusion of ACoA aneurysms is a safe method for the treatment of aneurysms. Patients with the aneurysm neck located at the A1-A2 junction and without A1 aplasia, who were treated with aneurysm sac and ACoA embolism, were potentially safe.

Dose reduction in cone-beam CT scanning for intracranial stent deployment before coil embolization of intracranial wide-neck aneurysms

PURPOSE

Flat panel detector (FD)-equipped angiography machines are increasingly used for neuro-angiographic imaging. During intracranial stent-assisted coil embolization procedures, it is very important to clearly and quickly visualize stent shape after deployment in the vessel. It is necessary to quickly visualize stents by cone-beam computed tomography (CBCT). The aim of this study was to compare CBCTs at 10 and 20 s, and to confirm that this method is useful for neuro-endovascular treatment procedures.

MATERIALS AND METHODS

We treated 30 patients with wide-necked intracranial aneurysms with a flexible, self-expanding neurovascular stent and subsequent aneurysm embolization with platinum micro-coils. We performed the CBCT after stent deployment. We compared the 10 s and 20 s CBCTs, using the full width one-half maximum (FWHM) visualization.

RESULTS

Accurate stent placement with subsequent coil occlusion of the aneurysms was feasible in all patients. Stent struts were clearly visualized on both 10 s and 20 s CBCTs. Importantly, 10 s CBCT can reduce the radiation dose by about 42%, compared with 20 s CBCT. Performing 10 s CBCT with a 14% dilution of the contrast medium may significantly improve image acquisition during stent-assisted coil embolization.

CONCLUSIONS

Reduced-dose, 10 s CBCT can visualize stents in clinical cases, while significantly reducing radiation exposure.

Clinical and Angiographic Outcomes of Aneurysms Treated with Two Self-expanding Stent-assisted Coiling Systems: A Comparison of Solitaire AB and Enterprise VRD Stents

OBJECTIVE

The purpose of this study was to compare clinical findings and outcomes of Enterprise and Solitaire stent-assisted coiling (SAC).

MATERIALS AND METHODS

Between January 2012 and March 2014, 86 patients (mean age, 60.3 years) harboring 89 aneurysms were treated with Enterprise (n = 57) or Solitaire (n = 32) SAC. The patients' demographics, angiographic results, and clinical outcomes were reviewed retrospectively.

RESULTS

There were no cases of stent navigation, deployment failure, arterial dissection, or intraoperative aneurysmal rupture. Angiographic follow-up imaging was available for 86 (96.6%) aneurysms (Enterprise group, n = 55; Solitaire group, n = 31). Immediate postoperative and follow-up angiographic results showed no flow or only minimal flow into the neck in 83% (Enterprise group, 77.2%; Solitaire group, 93.8%) and 95.3% (Enterprise group, 92.7%; Solitaire group, 100%) of SAC-treated aneurysms, respectively. Both stent groups showed good immediate postoperative and follow-up clinical outcomes. Excepting 2 cases, all patients achieved modified Rankin Scale scores of 0. Coil loop or tail protrusion into the parent artery was observed in 17 (29.8%) and 7 (21.9%) cases in the Enterprise and Solitaire groups, respectively. No statistically significant difference in terms of angiographic results or clinical outcomes was observed between the groups.

CONCLUSION

Excellent and comparable clinical and angiographic outcomes for wide-neck intracranial aneurysms were achieved using both stents. Because of its higher radial strength and better vessel wall apposition, we cautiously propose that the Solitaire stent may be more effective for SAC of aneurysms harboring a large or severe tortuous parent artery.

Stent-Assisted Coil Embolization of Intracranial Aneurysms: Complications in Acutely Ruptured versus Unruptured Aneurysms

BACKGROUND AND PURPOSE

The use of stents in the setting of SAH is controversial because of concerns about the efficacy and risk of dual antiplatelet therapy. We compare complications of stent-assisted coil embolization in patients with acutely ruptured aneurysms with complications in patients with unruptured aneurysms.

MATERIALS AND METHODS

Between February 2007 and March 2015, 45 acutely ruptured aneurysms and 47 unruptured aneurysms were treated with stent-assisted coiling. Patients with ruptured aneurysms were not pretreated with antiplatelet medication but received intravenous aspirin during the procedure. Thromboembolic events and early rebleeds were recorded.

RESULTS

In ruptured aneurysms, 9 of 45 patients had thromboembolic complications. Four patients remained asymptomatic, 4 developed infarctions, and 1 patient died. The permanent complication rate in ruptured aneurysms was 11% (95% CI, 4%-24%). Five of 45 patients (11%; 95% CI, 4%-24%) had an early rebleed from the treated aneurysm after 3-45 days, and in 4, this rebleed was fatal. In 46 patients with 47 unruptured aneurysms, thromboembolic complications occurred in 2. One patient remained asymptomatic; the other had a thalamus infarction. The complication rate in unruptured aneurysms was 2.2% (1 of 46; 95% CI, 0.01%-12%). No first-time hemorrhages occurred in 46 patients with 47 aneurysms during 6 months of follow-up.

CONCLUSIONS

The complication rate of stent-assisted coiling with early adverse events in ruptured aneurysms was 10 times higher than that in unruptured aneurysms. Early rebleed accounted for most mortality. In ruptured aneurysms, stent-assisted coil embolization is associated with increased morbidity and mortality and should only be considered when less risky options have been excluded.

Final results of the US humanitarian device exemption study of the low-profile visualized intraluminal support (LVIS) device

Introduction

The low-profile visualized intraluminal support (LVIS) device is a new, braided, intracranial microstent designed for stent-assisted coiling.

Objective

To present the results of a single-arm, prospective, multicenter trial of the LVIS for treatment of wide-necked intracranial aneurysms.

Methods

31 patients with unruptured, wide-necked (neck ≥4 mm or dome:neck ratio ≤2) intracranial aneurysms were treated with the LVIS device and bare platinum coils at six US centers (investigational device exemption G110014). Clinical follow-up was conducted at 30 days and 6 months. Angiographic follow-up was performed at 6 months. The primary safety endpoint was any major stroke or death within 30 days or major ipsilateral stroke or neurological death within 6 months. ‘Probable benefit’ was defined as ≥90% angiographic occlusion at 6 months. An independent core laboratory adjudicated the angiographic results. An independent clinical events committee adjudicated the clinical endpoints.

Results

Average aneurysm size was 7.2 mm (SD 3.8) and average neck width was 4.6 mm (SD 1.8). 68% of patients had a dome:neck ratio ≤2. LVIS placement was technically successful in 29/31 patients (93.5%). No primary safety endpoints occurred during the study (0%). No patient had a higher modified Rankin Score at 6 months than at baseline. 26/28 (92.9%) treated aneurysms with 6-month angiographic follow-up demonstrated ≥90% angiographic occlusion. 21/28 (75%) were completely occluded at follow-up.

Conclusions

The LVIS device facilitated the coil embolization of wide-necked intracranial aneurysms with high rates of technical success, an excellent safety profile, and very high rates of complete and near-complete occlusion at follow-up.

Trial registration number

NCT01541254.

Intraprocedural abciximab bolus versus pretreatment oral dual antiplatelet medication for endovascular stenting of unruptured intracranial aneurysms

Background

Standard pretreatment with dual antiplatelet medication (DAPM) was compared with a standalone intraprocedural abciximab bolus for the prevention of thromboembolic and hemorrhagic events during endovascular stenting of unruptured intracranial aneurysms.

Materials and methods

We treated 94 patients with 99 aneurysms with intracranial stenting (with or without coiling). Patients were either pretreated with DAPM daily for ≥3 days before stenting (pretreatment group) or received an abciximab bolus during or immediately after stent placement followed by postoperative DAPM (abciximab group), at the treating physician's discretion. Twenty patients underwent immediate postoperative MRI. Demographic, clinical, and radiological information and periprocedural complications were recorded.

Results

There were 52 procedures in the pretreatment group and 47 in the abciximab group. More flow-diverting stents were placed in the pretreatment group than in the abciximab group (45 vs 23, p<0.001), and the aneurysm diameter was larger (11.2±6.7 vs 8.3±4.7 mm, p=0.01). There were 11 thrombotic and 7 access site complications, with no significant difference between the groups (p>0.99 and p=0.12, respectively). There were no intracranial hemorrhages. In patients with postoperative MRI, there was no difference in the presence of diffusion-restricted lesions between groups (p=0.20). Multivariate analysis of a composite of any complication did not show significant associations with aneurysm or patient variables in either group.

Conclusions

Standalone intraprocedural abciximab bolus was not associated with an increased rate of complications compared with pretreatment with DAPM for unruptured intracranial aneurysm stenting.

Coil Embolization of Wide-Neck Bifurcation Aneurysms Using a Single-Balloon Microcatheter

BACKGROUND

Coil embolization of wide-neck cerebral aneurysms frequently requires stent or balloon assistance. Such approaches to coil embolization increase the procedural complexity, adding risk and cost.

OBJECTIVE

To describe a series of coil embolization procedures performed using a single-balloon microcatheter to treat wide-neck aneurysms and establish the safety, feasibility and efficacy of this technique.

METHODS

A retrospective review was performed to identify cases in which the Ascent balloon (Codman Neurovascular, Raynham, Mass., USA) was used as a single-balloon microcatheter for aneurysm coil embolization at two institutions. Clinical, demographic and angiographic data were obtained, and aneurysm volumes as well as packing densities (PD) were calculated.

RESULTS

Eight cerebral aneurysms were treated using this technique. Six of these were unruptured. The aneurysms had an average neck diameter of 3.7 mm, and the maximum dimension ranged from 5 to 11 mm, with a mean of 7.5 mm. The mean aspect ratio was 2.07. The mean volume of the aneurysms was 180.38 mm(3). The average PD achieved in these 8 aneurysms was 41.79%. Complete occlusion with coil embolization [Raymond-Roy Occlusion Classification (RROC) 1] was achieved in all cases except one, where a small residual was left deliberately and the occlusion grade was RROC 2. There were no intraprocedural complications.

CONCLUSION

This initial experience demonstrates the feasibility and immediate outcomes of a single-balloon microcatheter technique in coil embolization of wide-neck cerebral aneurysms. This technique may be used to achieve a high PD, comparable to that obtained with stent-assisted coiling or coiling alone, while avoiding permanent stent placement and potentially reducing thromboembolic complications.

Solitaire AB stent-assisted coiling of wide-necked intracranial aneurysms: mid-term results from the SOLARE Study

BACKGROUND

Endovascular treatment of intracranial aneurysms can be technically difficult when the neck is wide. The Solitaire AB stent (Covidien, Irvine, California), the only fully retrieved stent, assists in the coiling of wide-neck intracranial aneurysms.

OBJECTIVE

To evaluate the mid-term angiographic follow-up of wide-necked aneurysms treated with the Solitaire AB stent.

METHODS

SOLARE (SOLitaire Aneurysm Remodeling) is a consecutive, prospective study conducted in 7 European centers. A core laboratory evaluated the postoperative and mid-term (6 month ± 15 days) angiographic results by using the Raymond classification Scale. Recanalization was defined as worsening, and progressive thrombosis was defined as improvement in the Raymond scale score.

RESULTS

The mean width of the aneurysm sac was 7.5 mm, and the mean diameter of the aneurysm neck was 4.7 mm. Angiographic mid-term follow-up was obtained in 55 of 65 aneurysms (85.9%). Complete occlusion was achieved in 33 aneurysms (60%); a neck remnant was seen in 16 aneurysms (29.1%) and an aneurysm remnant in 6 aneurysms (10.9%). Of 55 aneurysms, recanalization was observed in 8 aneurysms (14.5%), and progressive thrombosis was observed in 17 aneurysms (30.9%). No bleeding or rebleeding was observed during the follow-up period.

CONCLUSION

Stent-assisted coiling of wide-necked intracranial aneurysms was found to be safe and effective with the Solitaire AB stent at 6-month follow-up. Angiographic results improve with time due to progressive thrombosis of the aneurysm.

Comparison between Solitaire™ AB and Enterprise stent-assisted coiling for intracranial aneurysms

The aim of the present study was to analyze the feasibility, rate of procedure-related complications and midterm angiographic follow-up outcomes using the Enterprise (EP) and Solitaire™ AB (ST) stents in the stent-assisted coiling of intracranial aneurysms. In total, 81 patients with 90 aneurysms were included in the study, with the aim to treat 43 aneurysms with the EP stent (47.8%) and 47 aneurysms with the ST stent (52.2%). The 90 aneurysms were successfully stented and subsequently coiled; however, in four patients undergoing treatment with the EP stent, the stent was not navigable; thus, treatment with the ST stent was employed (EP, n=39, 43.3%; ST, n=51, 56.7%). Of the 90 aneurysms, 44 cases were ruptured aneurysms, with 74 located in the anterior circulation and 16 located in the posterior circulation. The stenting success rate of the ST stent was significantly higher compared with the EP stent. However, no statistically significant differences were observed with regard to the packing density, complete occlusion, progressive occlusion, recurrence rate, procedure-related complications, in-stent stenosis and stent migration rates between the two groups. In conclusion, the two common medical devices used for intracranial aneurysms are relatively safe and effective for the treatment of intracranial aneurysms. However, due to the higher stenting success rate of the ST stent, this medical devise was demonstrated to be more flexible and feasible compared with the EP stent.

Enterprise stent-assisted coiling for wide-necked intracranial aneurysms during ultra-early (48hours) subarachnoid hemorrhage: a single-center experience in 59 consecutive patients

BACKGROUND AND OBJECTIVE

Accumulated experience and improvement of stents dedicated to intracranial use have significantly widened the applicability of stent-assisted coiling (SAC) to ruptured wide-necked aneurysms. This retrospective study was designed to evaluate the safety and efficacy of SAC using the Enterprise stent for ruptured wide-necked intracranial aneurysms during ultra-early subarachnoid hemorrhage.

METHOD

We reviewed data from 59 consecutive patients with ruptured wide-necked aneurysms who had SAC using the Enterprise stent performed within 48hours of onset. Data collected and analyzed included: patient demographics; morphologic features of the aneurysm; treatment results and follow-up results. Clinical outcomes were evaluated by modified Rankin Scale (mRS).

RESULTS

In all 59 cases, SAC using the Enterprise stent was performed successfully, with no significant technical difficulties. Initial angiographic results were: complete occlusion in 38 cases; near occlusion in 17; and partial occlusion in four. Angiographic follow-up of 48 patients showed that 46 (95.8%) remained stable or improved, without regrowth, while regrowth was imaged in two patients. Medium-term clinical follow-up of 54 patients (mean, 26.9months) showed that 88.9% had a good outcome (mRS: 0 in 34; 1 in eight; and 2 in six), and 11.1% poor outcomes (mRS: 3 in four; and 4 in two).

CONCLUSION

Enterprise SAC is a safe and viable option for treatment of ruptured wide-necked aneurysms within 48hours of ictus.

Preliminary experience with self-expanding closed-cell stent placement in small arteries less than 2 mm in diameter for the treatment of intracranial aneurysms

OBJECT

The purpose of this study was to report the authors' preliminary experience using self-expanding closed-cell stents deployed in small arteries (< 2 mm in diameter) to treat intracranial aneurysms.

METHODS

A total of 31 patients were studied. All subjects met the following criteria: 1) they received an Enterprise stent for treatment of a wide-necked aneurysm or a dissecting aneurysm or as part of a stent-salvage procedure; and 2) they had an Enterprise stent deployed in a small parent artery (< 2 mm in diameter) that had no atherosclerotic stenosis. Procedure-related complications and follow-up sizes of the parent arteries were evaluated for safety and patency.

RESULTS

There were 16 ruptured aneurysms and 15 unruptured aneurysms. Three (9.7%) of the 31 patients experienced procedure-related complications, and they all were asymptomatic. Follow-up angiography was performed in 27 patients (87.1%) (at a mean 15.5 months after surgery). Parent arteries with 2 acute angles (n = 4) were occluded in 3 cases (75.0%), and those with no acute angles (n = 13) or 1 acute angle (n = 6) showed 100% patency on follow-up angiography. There was a significant difference between the follow-up sizes (mean 1.72 ± 0.30 mm) of parent arteries and their sizes (mean 1.59 ± 0.26 mm) before treatment (95% CI - 0.254 to - 0.009 mm; p = 0.037, paired-samples t-test).

CONCLUSIONS

In the current series the deployment of self-expanding closed-cell stents in small arteries was safe and resulted in good patency, especially when the stents were deployed in segments of the parent artery with no acute angles or only 1 acute angle.

Assisted coiling of saccular wide-necked unruptured intracranial aneurysms: stent versus balloon

BACKGROUND AND PURPOSE

Assisted coiling with stents or balloons enables a higher percentage of complete occlusions of saccular unruptured intracranial aneurysms to be achieved with a reasonable complication rate. The aim of this study was to compare stent-assisted coiling and the balloon remodeling technique in terms of efficacy, stability, and safety for the treatment of comparable unruptured saccular intracranial aneurysms.

MATERIALS AND METHODS

268 patients with 286 saccular unruptured wide-necked intracranial aneurysms were treated at our institution with stent- or balloon-assisted coiling and retrospectively reviewed. Statistical analysis was performed to assess significant differences between the two groups.

RESULTS

The rate of complete occlusion at the end of the procedure was higher with stent-assisted coiling than with balloon-assisted coiling (86.8% vs 78%) and the same results were also observed after 6 months (92.1% vs 77.6%; p=0.05). About 50% of major recurrences occurred in large to giant aneurysms (p<0.001). The overall complication rate was similar in the stent-assisted and balloon-assisted groups (10.3% vs 9.3%). Independently of the technique, a higher complication rate was observed with bifurcational aneurysms, particularly in the middle cerebral artery (p=0.016).

CONCLUSIONS

Stent-assisted coiling achieved better results in terms of complete occlusion and stability than balloon-assisted coiling with a lower rate of recurrence without being associated with a higher risk of intraprocedural complications. Bifurcational and large to giant aneurysms were associated with higher complication rates and higher recurrence rates, respectively, and still represent a challenge for both techniques.

Single-center experience with a dual microcatheter technique for the endovascular treatment of wide-necked aneurysms

Object

The endovascular treatment of wide-necked aneurysms can be technically challenging due to distal coil migration or impingement of the parent vessel. In this paper, the authors illustrate an alternative method for the treatment of wide-necked intracranial aneurysms using a dual microcatheter technique.

Methods

The authors' first 100 consecutive patients who underwent coil embolization of a wide-necked aneurysm using a dual microcatheter technique are reported. With this technique, 2 microcatheters are used to introduce coils into the aneurysm. The coils are deployed either sequentially or concurrently to form a stable construct and prevent coil herniation or migration. Angiographic and clinical outcomes are reported.

Results

The technical success rate of the dual microcatheter technique is 91% with a morbidity and mortality of 1% and 2%, respectively. Clinical outcomes are excellent with 93% of patients demonstrating a modified Rankin Scale score of 0–2 at long-term follow-up regardless of their score at presentation. Retreatment rates are 18%.

Conclusions

The dual microcatheter technique may be a safe and efficacious first line of treatment for widenecked aneurysms.

Use of buddy wire to facilitate Y-configured stent placement in middle cerebral artery bifurcation aneurysms with daughter branches arising from the sac: a technical note

BACKGROUND AND IMPORTANCE

Endovascular treatment of geometrically complex bifurcation aneurysms using a standard Y-configured stenting technique might be extremely difficult, particularly in aneurysms with daughter branches that acutely arise from the aneurysm sac itself. In those cases, deployment of the second stent through interstices of the first stent could be troublesome because of untoward angular changes in the vascular bifurcation prompted by angular changes resulting from placement of the first stent. Here, we describe a novel application of the buddy wire technique to facilitate Y-configured stenting in middle cerebral artery (MCA) bifurcation aneurysms with unfavorable anatomic configuration.

CLINICAL PRESENTATION

A 60-year-old man with a left-sided MCA bifurcation aneurysm was treated using the buddy wire technique. In addition to the standard Y-configured stenting procedure, we also inserted a 0.014-inch exchange microguidewire into the superior daughter branch, which more acutely emanated from the sac, to attain a favorable bifurcation configuration before deployment of the stents in the Y configuration. The new technique was successful, and the postprocedural course of the treatment was uneventful.

CONCLUSION

Use of a buddy wire in MCA bifurcation aneurysms with unfavorable anatomic configurations may be a promising method to facilitate Y-configured stent placement.

Ocular thrombosis after stent-assisted coiling of a c7 (paraclinoid) internal carotid artery aneurysm. A report of two cases and literature review

Stent-assisted coiling of paraclinoid aneurysms is widely performed in neurointerventional surgery. The most common adverse event related to this procedure is cerebral thromboembolism. However, reports on ocular thromboembolism are scarce. We report our experience with two patients who developed ocular thromboembolism following Enterprise stent-assisted coiling of paraclinoid aneurysms. We then review the available literature for the possible pathomechanism of ocular thrombosis. Ocular thromboembolism may be a risk of stent-assisted coiling when the stent traverses the orifice of the ophthalmic artery or the stent is placed in the C3 internal carotid artery. Further study is needed to clarify how to avoid this disabling complication.

Balloons in endovascular neurosurgery: history and current applications

The use of balloons in the field of neurosurgery is currently an essential part of our clinical practice. The field has evolved over the last 40 years since Serbinenko used balloons to test the feasibility of occluding cervical vessels for intracranial pathologies. Since that time, indications have expanded to include sacrificing cervical and intracranial vessels with detachable balloons, supporting the coil mass in wide-necked aneurysms (balloon remodeling technique), and performing intracranial and cervical angioplasty for atherosclerotic disease, as well as an adjunct to treat arteriovenous malformations. With the rapid expansion of endovascular technologies, it appears that the indications and uses for balloons will continue to expand. In this article, we review the history of balloons, the initial applications, the types of balloons available, and the current applications available for endovascular neurosurgeons.

Multimodality treatment of complex unruptured cavernous and paraclinoid aneurysms

BACKGROUND

Unruptured aneurysms of the cavernous and paraclinoid internal carotid artery can be approached via microsurgical and endovascular approaches. Trends in treatment reflect a steady shift toward endovascular techniques.

OBJECTIVE

To analyze our results with multimodal treatment.

METHODS

We reviewed patients with unruptured cavernous and paraclinoid internal carotid artery aneurysms proximal to the posterior communicating artery treated at a single center from 2007 to 2012. Treatment included 4 groups: (1) stent-assisted coiling, (2) pipeline endovascular device (PED) flow diverter, (3) clipping, and (4) trapping/bypass. Follow-up was 2 to 60 months.

RESULTS

The 109 aneurysms in 102 patients were studied with the following treatment groupings: 41 were done with stent-assisted coiling, 24 with Pipeline endovascular device, 24 by microsurgical clipping, and 20 by trap/bypass. Group: (1) two percent had delayed significant intraparenchymal hemorrhage; (2) thirteen percent had central nerve palsies, 8% had small asymptomatic infarcts, and 4% had small, asymptomatic remote-site hemorrhages; (3) twenty-nine percent of patients suffered from transient central nerve palsies, 4% experienced major stroke, and 8% had small intracerebral hemorrhages; (4) thirty-five percent had transient central nerve palsies, 10% had strokes, and 10% had intracerebral hemorrhages. In terms of follow-up obliteration, 83% had complete/nearly complete obliteration at last follow-up, 17% had residual aneurysms, and 10% required retreatment. Ninety-six percent of group 1 (35/38), 100% of group 2 (23/23), 100% of group 3 (21/21), and 95% of group 4 had modified Rankin Scale scores of 0 to 1.

CONCLUSION

Treatment of these aneurysms can be carried out with acceptable rates of morbidity. Careful patient selection is crucial for optimal outcome. Endovascular treatment volumes likely will continue to predominate over microsurgical techniques as changing skill sets evolve in neurosurgery, but individualized application of all available treatment options will continue.

Comparison of clinical and radiologic outcomes among stent-assisted, double-catheter, and balloon-assisted coil embolization of wide neck aneurysms

BACKGROUND

Endovascular treatment of intracranial aneurysms can be technically challenging in cases of wide necks or unfavorable dome-to-neck ratio. Coils deployed without supporting devices may herniate from the aneurysm sac into the parent artery, causing thromboembolic complications or vessel occlusion. Therefore, alternative strategies for managing wide-necked aneurysms have been introduced such as stent-assisted coil embolization (SAC), balloon-assisted coil embolization (BAC), and double-catheter coil embolization (DCC).

METHODS

SAC, BAC, or DCC were used to treat 201 patients with 207 wide-neck aneurysms between 2008 and 2013. Initial occlusion rates, recanalization rates, and periprocedural complications were retrospectively evaluated. The mean follow-up periods for SAC, BAC, and DCC were 16.2 months, 11.6 months, and 14.3 months, respectively.

RESULTS

Clinical and anatomical analyses were conducted in 201 patients with 207 anuerysms. Complete occlusion rates of SAC, DCC, and BAC were 63.8 %, 46.7 %, and 63.2 %, respectively, and incomplete occlusion rates were 13.4 %, 15.5 %, 10.5 %, respectively (p value = 0.798). No rebleeding or hemorrhage occurred after coil embolization. Recanalization rates did not differ among the SAC, DCC, and BAC groups (7.1 % vs. 11.1 % vs. 7.9 %, p value = 0.696). Statistically insignificant results were observed in the rate of periprocedural complications among SAC, DCC, and BAC (11.0 % vs. 13.3 % vs. 15.8 %, p value = 0.578).

CONCLUSIONS

There were no significant differences in the recurrence rate and periprocedural complication rate, and no rebleeding or aneurysmal rupture after treatment. Sufficient occlusion rates were achieved with SAC, DCC, and BAC. Notably, DCC does not require the use of antiplatelet agents and achieves coil stability without compromising the parent artery or major branch. Thus, we believe that the double-catheter technique was found to be a feasible and safe treatment modality for branching wide-neck aneurysms.

Giant vertebral artery aneurysm in a child treated with endovascular parent artery occlusion and coil embolization

Background:

Intracranial giant vertebral artery aneurysms are extremely rare in the pediatric population and are associated with significant morbidity and mortality. The present report describes a case of a pediatric patient with giant vertebral artery aneurysm who presented with intracranial mass effect. This patient was successfully treated with endovascular parent artery occlusion and coil embolization.

Case Description:

A 7-year-old girl presented with tetraparesis, ataxia, dysphagia, and dysphonia. Cerebral angiography revealed intracranial giant aneurysm arising from the right vertebral artery. The patient underwent endovascular parent artery occlusion alone to facilitate aneurysmal thrombosis as an initial treatment. This was done to avoid a coil mass effect to the brainstem. However, incomplete thrombosis occurred in the vicinity of the vertebral artery union. Therefore, additional coil embolization for residual aneurysm was performed. Two additional coil embolization procedures were performed in response to recurrence. Mass effect and clinical symptoms gradually improved, and the patient had no associated morbidity or recurrence at 2 years after the last fourth coil embolization.

Conclusion:

Intracranial giant vertebral artery aneurysms are rare and challenging in pediatric patients. Staged endovascular strategy can be a safe and effective treatment option.

Treatment of intracranial aneurysms by flow diverter devices: long-term results from a single center

OBJECTIVES

Flow-Diverter Devices (FDD) are a new generation stents designed for the treatment of the intracranial aneurysms. This article reports the long-term results (2-4 years) of this treatment from a single-center.

METHODS

From November 2008 to January 2012, 35 patients (29 females and 6 males; mean age 53.9 y) with 39 intracranial aneurysms were treated by FDD. Five patients (14.3%) had ruptured aneurysms and 30 (85.7%) had no previous hemorrhage. The procedures were performed in 5 patients (14.3%) with SILK and in 30 (85.7%) with PED. In 3 patients FDDs were used as a second treatment after failure of previous coiling (2 cases) or stenting (one case). The 39 aneurysms were in supraclinoid ICA in 26 (66.7%), cavernous ICA in 2 (5.1%), PCoA in 4 (10.2%), MCA in 5 (12.9%), SCA in 1 (2.6%) and PICA in 1 (2.6%). The aneurysms were small (<10mm) in 32 cases (82%), large (11-25mm) in 6 (15.3%) and giant in 1 (2.6%). The occlusion rate according to the aneurysm location, size and neck and the complications were evaluated.

RESULTS

Peri-procedural complications included transient dysarthria (2 patients), vasospasm with acute intra-stent aggregation (one), microwire rupture (one) and failure of the stent opening (one). The follow-up was made between 24 and 62 months (mean 41 months); clinical examination and CTA were performed at 1, 3, 6 and 12 months after the procedure. The complete occlusion was confirmed by CTA and DSA. MRI with angiographic-studies was taken every year. Complete occlusion was obtained in 35 aneurysms (92.1%) and subtotal in 3 (7.9%). Complete occlusion occurred at 3 months in 24 cases (68.6%), within 3 and 6 months in 9 (25.7%). The rate and time of complete occlusion were not correlated with the aneurysm size. MCA aneurysms mainly showed partial occlusion (2/3 cases). Besides, large-neck aneurysms and those with a vessel arising from the sac mainly showed late (>6 months) or partial occlusion.

CONCLUSION

FDD are a safe and efficacious treatment of intracranial aneurysms, resulting in high occlusion rate and low incidence of complications. It should be the treatment of choice for the large-neck aneurysm of the ICA.

Stent-assisted coil embolization of ruptured wide-necked aneurysms in the acute period: incidence of and risk factors for periprocedural complications

OBJECT.: The purpose of this study was to report the authors' experiences in stent-assisted coil embolization (SAC) of ruptured wide-necked aneurysms in the acute period and to evaluate the incidence of and risk factors for periprocedural complications.

METHODS

A total of 72 patients were recruited for this study between March 2007 and June 2012. All patients met the following criteria: 1) the presence of ruptured intracranial wide-necked saccular aneurysms, and 2) the patient underwent SAC for treatment of those aneurysms within 72 hours of rupture. All of the patients with clinically poor grades or acute hydrocephalus underwent external ventricular drainage (EVD) before SAC. The incidence of and risk factors for periprocedural complications were retrospectively evaluated.

RESULTS

Of the 72 patients included in this study, periprocedural complications occurred in 14 (19.4%), including asymptomatic complications in 4 (5.6%) and symptomatic complications in 10 (13.9%); there were symptomatic thromboembolic complications in 5 patients (6.9%), and symptomatic hemorrhagic complications in 5 (6.9%). The authors observed no subacute or delayed thromboembolic complications during the follow-up period of 18.8 months. Use of EVD (OR 1.413, 95% CI 0.088-2.173; p = 0.046) was the only independent risk factor for periprocedural complications on multivariate logistic regression analysis.

CONCLUSIONS

The periprocedural complication rate during SAC was 19.4% among 72 patients. Because of the high complication rate, microsurgical clipping or endovascular treatment with another technique (multiple-microcatheter or balloon-assisted technique) may be a more appropriate option for first-line treatment than SAC, especially in patients requiring EVD.

Coil embolization of intracranial saccular aneurysms using the Low-profile Visualized Intraluminal Support (LVIS™) device

INTRODUCTION

The novel Low-profile Visualized Intraluminal Support (LVIS™, LVIS and LVIS Jr.) device was recently introduced for stent-supported coil embolization of intracranial aneurysms. Periprocedural and midterm follow-up results for its use in stent-supported coil embolization of unruptured aneurysms are presented herein.

METHODS

In this prospective multicenter study, clinical and radiologic outcomes were analyzed for 55 patients with saccular aneurysms undergoing LVIS-assisted coil embolization between October 2012 and February 2013. Magnetic resonance angiography or digital subtraction angiography was performed to evaluate midterm follow-up results.

RESULTS

The standard LVIS device, deployed in 27 patients, was more often used in internal carotid artery (ICA) aneurysms (n=19), whereas the LVIS Jr. (a lower profile stent, n=28) was generally reserved for anterior communicating artery (n=14) and middle cerebral artery (n=8) aneurysms. With LVIS-assisted coil embolization, successful occlusion was achieved in 45 aneurysms (81.8 %). Although no instances of navigation failure or stent malposition occurred, segmentally incomplete stent expansion was seen in five patients where the higher profile LVIS was applied to ICA including carotid siphon. Procedural morbidity was low (2/55, 3.6 %), limited to symptomatic thromboembolism. In the imaging of lesions (54/55, 98.2 %) at 6-month follow-up, only a single instances of major recanalization (1.9 %) occurred. Follow-up angiography of 30 aneurysms (54.5 %) demonstrated in-stent stenosis in 26 (86.7 %), with no instances of stent migration. Only one patient suffered late delayed infarction (modified Rankin Scale 1).

CONCLUSION

The LVIS device performed acceptably in stent-assisted coil embolization of non-ruptured aneurysms due to easy navigation and precise placement, although segmentally incomplete stent expansion and delayed in-stent stenosis were issues.

A Self-expanding Nitinol Stent (Enterprise) for the Treatment of Wide-necked Intracranial Aneurysms: Angiographic and Clinical Results in 40 Aneurysms

Objective

Self-expanding stents are increasingly used for the treatment of complex intracranial aneurysms. The purpose of this study was to evaluate the usefulness and safety of a self-expanding nitinol stent (Enterprise) in the treatment of wide-necked intracranial aneurysms.

Methods

This was a retrospective study of 39 patients with 40 wide-necked intracranial aneurysms who were enrolled in a single-center registry of patients treated with the Enterprise between June 2009 and December 2011. Thirty patients were asymptomatic, four had cerebrovascular accident sequelae, and five had suffered subarachnoid hemorrhage. One aneurysm had reopened after prior coil embolization, while 39 had not been treated. Clinical charts, procedural data, and angiographic results, including both immediate post-procedural angiograms and follow-up imaging, were reviewed.

Results

The mean neck size of the aneurysms was 5.58 mm (range 3-15.1 mm). Embolization was successful in all patients. There were five procedure-related events. There were no fatalities, but one procedure-related morbidity was noted. The immediate angiographic results included eight complete occlusions (20%), six remnant necks (15%), and 26 remnant sacs (65%). At angiographic follow-up (mean: 11.3 months), out of 18 of the aneurysms treated with stent-assisted coiling, there were 13 (72.2%) complete occlusions, four (22.2%) remnant necks, and one recanalization (5.6%).

Conclusion

Stent-assisted coiling using the Enterprise is effective for the treatment of wide-necked intracranial aneurysms. Further angiographic and clinical follow-up investigation will be needed for evaluation of the long-term outcomes.

Low-profile Visualized Intraluminal Support device (LVIS Jr) as a novel tool in the treatment of wide-necked intracranial aneurysms: initial experience in 32 cases

BACKGROUND AND PURPOSE

The focus of this study was to determine ease of deployment, safety and effectiveness of the LVIS Jr device.

METHODS

A retrospective analysis was performed of 32 cases comprising 34 aneurysms in which the LVIS Jr device was used for stent-assisted coil embolization of intracranial aneurysms from February to October 2012, including all clinical and angiographic data as well as mid-term follow-up (1-12 months of treatment).

RESULTS

The median age of the patients was 54 years (range 21-76) and 19 (59%) were women. The aneurysms were ruptured in 12/34 cases (35.3%); 26 (76.4%) were located within the anterior circulation and the remaining 8 (23.5%) were located in the posterior circulation. Eleven of the 34 aneurysms (32.3%) were treated with a Y-stent configuration. Immediate total occlusion was observed in 16/34 (47%), near total occlusion (90-95%) in 5/34 (14.7%) and a 'dog ear' or subtotal occlusion in 12/34 (35.2%). A single aneurysm was treated without coil embolization. Complications occurred in 5/34 cases (15%), including two cases of in-stent thrombosis.

CONCLUSIONS

Implantation of the LVIS Jr device as a support device for stent-assisted coil embolization seems to be safe and effective. The LVIS Jr device can also be implanted in a Y-stent configuration, offering a novel technique with a potentially lower risk of thromboembolic complications compared with other devices.

Analysis of closed-cell intracranial stent characteristics using cone-beam computed tomography with contrast material

The intracranial nitinol stent named the Enterprise Vascular Reconstruction Device has poor radiographic visibility. The characteristics of closed-cell intracranial stents were investigated and the efficacy of intraoperative stent visualization examined with the 80 kV high-resolution XperCT protocol, which is a flat detector C-arm volume acquisition functionality system integrated with the angiography equipment. We treated 39 aneurysms with stent-assisted coil embolization. The aneurysms were located on the internal carotid artery in 24 cases, the anterior communicating artery (AcomA) in three, the basilar artery (BA) in 10, and the vertebral artery in two. Intraoperative 80 kV XperCT was performed in all cases after deposition of the stent. We evaluated the coverage of the aneurysm neck, incomplete stent apposition (ISA), and shift of vessels. Accurate stent visualization was achieved in 29 of the 39 cases without coil and delivery wire artifact. Coverage of the aneurysm neck succeeded in 28 cases; there was one case of BA top Y-configuration stenting in which the stent was dislocated into the aneurysm. ISA was detected in nine cases, including seven kinks and one flattening in the carotid siphon and one kink in the BA top. We detected linearization of vessels due to stent deployment in three AcomA cases and three BA top cases. We conclude that intraoperative 80 kV XperCT is an efficient modality for the evaluation of ISA. Stent kinking in the carotid siphon and linearization in distal vessels can be detected with this protocol.

Patient selection for endovascular treatment of intracranial aneurysms

With recent advancement in medical imaging, techniques, and endovascular tools more patients are diagnosed with unruptured intracranial aneurysms. The main aim of offering aneurysm treatment is to ameliorate the risk of future aneurysm bleeding, while not posing additional risks on the patient from the treatment itself. We discuss in this paper our approach of selecting patients for treatment (simple coiling, balloon-assisted, stent-assisted, vessel sacrifice, or flow-divertion stents). Our decision-making is based on the published data and our center experience. Risks of all option are compared to each other and weighed against natural history of intracranial aneurysms. In this paper, literature is cited and case illustrations are presented to support this approach. Factors that affect our decision-making are aneurysm location, presentation, size, aneurysm geometry, parent vessel anatomy, and relevant co-morbidities.

Changes in hemodynamics after placing intracranial stents

Stent-assisted coil embolization has enabled the endovascular treatment of wide-necked cerebral aneurysms. Moreover, recent reports demonstrated that stent-assisted coil embolization was associated with a significant decrease in angiographic recurrences of coiled cerebral aneurysms. One of the possible explanations for this adjunctive effect of stent-assisted coil embolization is changes in the local hemodynamics caused by placing intracranial stents. This study investigated the hemodynamic effect of intracranial stents using computational fluid dynamics (CFD) analysis. The geometry of the intracranial stent, Enterprise(TM) VRD, was acquired by using micro computed tomography and virtually placed across the aneurysm orifice of a saccular aneurysm model (saccular model) and a blister-like aneurysm model (blister-like model) constructed from patient-specific three-dimensional (3D) rotational angiography data. Transient CFD analysis was performed with these models with and without stents. Stent placement induced no significant changes in the 3D streamline in the saccular model and slight changes in the blister-like model. Both saccular and blister-like models with stents had lower wall shear stress (WSS) and flow velocity, and higher oscillatory shear index, WSS gradient, and relative residence time than the equivalent models without stents, indicating the possibility that stent placement induced stagnant and disturbed blood flow. Cross-sectional vector velocity around the stent strut revealed complex blood flow patterns with variable direction and velocity. Although this study was a simulation under limited conditions, similar hemodynamic changes might be induced in the neck remnants treated with stent-assisted coil embolization.

Advances in Endovascular Approaches to Cerebral Aneurysms

Recent advancements in all phases of endovascular aneurysm treatment, including medical therapy, diagnostics, devices, and implants, abound. Advancements in endovascular technologies and techniques have enabled treatment of a wide variety of intracranial aneurysms. In this article, technical advances in endovascular treatment of cerebral aneurysms are discussed, with an effort to incorporate a clinically relevant perspective. Advancements in diagnostic tools, medical therapy, and implants are reviewed and discussed.