Long-term Results of Enterprise Stent-Assisted Coiling of Cerebral Aneurysms

Comparative Analysis of the Low-Profile Acclino Stent and the Enterprise Stent for the Treatment of Unruptured Intracranial Aneurysms

OBJECTIVE

In preliminary studies, advanced intracranial stents appear to have a favorable safety profile for intracranial aneurysm treatment. This dual-center study is a head-to-head comparison of the low-profile Acandis Acclino stent (a third-generation stent) and the first- and second-generation Enterprise stent.

METHODS

Patients who underwent stent-assisted coiling with either the Enterprise or the Acclino stent for unruptured aneurysms during an 8-year period were enrolled and compared for complications, clinical outcomes, and angiographic results. Primary outcome measures were ischemic stroke rate and mid-term complete occlusion rate. Propensity score adjustment was performed to account for small differences between the groups.

RESULTS

Enterprise and Acclino stents were used in 48 cases each. The overall rate of thrombotic complications was higher in the Enterprise group than in the Acclino group (20.8% vs. 4.2%, HR: 6.6, 95%CI: 2.2-20.0, P = 0.01, adjusted P < 0.01), which translated into a higher rate of major ischemic stroke after Enterprise treatment (6.3% vs. 0%, HR: 2.1, 95%CI: 1.8-2.4, P = 0.08, adjusted P < 0.01). Mid-term and long-term angiographic follow-up showed complete occlusion rates of 83.3% and 75.0% for Enterprise and 89.2% and 75.9% for Acclino (both P > 0.05). Retreatment rates were 10.4% in the Enterprise group and 4.2% in the Acclino group (P = 0.42, adjusted P = 0.10).

CONCLUSIONS

The results indicate a favorable safety profile of the Acclino over the Enterprise, justifying the use of advanced stent systems in clinical practice. However, further comparative studies of the Acclino and other competing stent systems are needed to draw a definitive conclusion on the state of stent-assisted coiling.

Long-term results of wide-necked intracranial bifurcation aneurysms treated with stent-assisted coiling using low-profile acandis acclino stents

PURPOSE

Little data exists on endovascular treatment of complex intracranial aneurysms with the Acandis Acclino low-profile self-expanding closed-cell stent systems and is mainly limited to short- or midterm results. We report our long-term, single-centre experience with three generations of Acclino stents treating complex intracranial aneurysms.

METHODS

62 wide-necked intracranial aneurysms were treated electively using 88 Acclino stent systems. Single stent-assisted coiling was the preferred treatment in 38 cases and the kissing-Y stenting technique in 24 cases. We analysed demographic data and long-term follow-up results.

RESULTS

All stents were successfully deployed with immediate complete (Raymond Roy occlusion classification, RROC I) or near-complete occlusion (RROC II) achieved in 93,5%. Follow-up was available in 55 cases with a mean follow-up of 36 months (range 9-80 months). Long-term RROC I or II was achieved in 49 cases (89,1%). Three cases of stable residual aneurysmal filling were observed (5,5%). Seven aneurysms (12,7%) demonstrated a worsening on follow-up leading either to a neck remnant (4 cases, 7,3%) or to an aneurysm recurrence (3 cases, 5,5%). One recurrent aneurysm was retreated with coilembolization (1,8%). The directly procedural-related complication rate was 4,8%. Seven cases of clinically silent in-stent stenosis (12,7%; morbidity n = 0) were detected on long-term follow-up, six of them using the kissing-Y stenting technique.

CONCLUSION

Endovascular treatment of various intracranial aneurysms using the Acandis Acclino stent systems is safe and efficient with high aneurysm occlusion rates combined with low complication rates on long-term follow-up. Overall, rates of in-stent stenosis are low but may depend on the treatment technique (single stent-assisted coiling versus kissing-Y stenting with coiling).

Retreatment with a pipeline embolization device for recanalized aneurysms following stent-assisted coiling embolization

Background and purpose

Flow diverters have emerged as viable alternatives for the retreatment of recanalized aneurysms following stent-assisted coiling embolization. In this study, we aim to present our experience of retreatment for such aneurysms using the pipeline embolization device (PED).

Materials and methods

This case series presents a retrospective single-center analysis of patients with recanalized aneurysms who underwent retreatment using the PED between July 2019 and April 2023, subsequent to stent-assisted coiling embolization.

Results

The study includes five female patients, whose relevant clinical data were recorded. All patients had aneurysms located in the internal carotid artery, comprising two blood blister-like aneurysms and two giant aneurysms. Prior to the retreatment, two LVIS stents, two enterprise stents, and one solitaire stent were implanted. Among the five patients, one experienced a fatal post-operative subarachnoid hemorrhage, while two patients achieved complete embolization, and another patient achieved near-complete embolization during the last follow-up. Furthermore, one patient faced challenges during the placement of the PED and was unable to achieve successful deployment. We propose four overlapping relationships between a newly implanted PED and a previously deployed stent: (1) PED covering only the proximal end of the previous stent, (2) PED covering only the distal end of the previous stent, (3) PED covering both the proximal and distal ends of the previous stent, and (4) PED deployed within the previous stent. Antiplatelet therapy at our center involved daily dual therapy with aspirin (100 mg/day) and clopidogrel (75 mg/day) for at least 5 days before PED placement. Intra-arterial bolus administration of tirofiban (5 mcg/kg) was administered during or immediately after PED deployment, followed by a maintenance dose of 0.08 mcg/kg/min IV infusion for at least 24-48 h if necessary. Postprocedural dual antiplatelet therapy included clopidogrel (75 mg/day) for 6 months and aspirin (100 mg/day) for 12 months.

Conclusion

The findings of this study support the efficacy of the PED for the retreatment of recanalized aneurysms following stent-assisted coiling embolization.

Coiling Variations for Treatment of Ruptured Intracranial Aneurysms: A Meta-Analytical Comparison of Comaneci-, Stent-, and Balloon-Coiling Assistance Techniques

BACKGROUND

Wide-necked aneurysms represent a challenge for treatment in the setting of acute subarachnoid hemorrhage. Stent-assisted coiling (SAC) and balloon-assisted coiling (BAC) are well-known techniques for treating wide-necked aneurysms. Comaneci-assisted coiling (CAC) is a newer technique involving temporary stent deployment to assist aneurysm coiling. We aim to present the first meta-analysis comparing these treatments of ruptured aneurysms.

METHODS

Following PRISMA guidelines, PubMed and Embase databases were queried from earliest records to July 2022 for literature reporting SAC, BAC, or CAC of ruptured intracranial aneurysms. A meta-analysis of identified articles was performed.

RESULTS

Of the 571 articles queried, 64 articles were included. One study reported BAC and SAC, 8 reported BAC, 52 reported SAC, and 3 reported CAC. These studies comprised 3153 patients with 3207 ruptured aneurysms treated with CAC (161 patients and aneurysms), BAC (330 patients and aneurysms), and SAC (2662 patients, 2716 aneurysms). Rates of periprocedural thromboembolic or hemorrhagic complications, overall or procedure-related mortality, immediate complete occlusion, retreatment, and length of angiographic follow-up did not differ significantly between SAC and BAC. Periprocedural thromboembolic (P = 0.03) and hemorrhagic (P = 0.01) complication rates were higher with BAC than CAC. Periprocedural thromboembolic (P = 0.03) and hemorrhagic (P < 0.0001) complication rates were higher with SAC than CAC. Complete aneurysm occlusion rates (P = 0.033) were higher with CAC than BAC. No significant differences were present in CAC versus BAC or SAC retreatment rates.

CONCLUSIONS

CAC was associated with lower hemorrhagic and thromboembolic complication rates and demonstrated similar complete occlusion and residual retreatment rates to those for BAC and SAC.

Additional rescue stenting with Neuroform Atlas stents during stent-assisted coiling of saccular aneurysms

OBJECTIVE

Overlapping stenting is sometimes attempted during endovascular treatment of cerebral aneurysm as a rescue for coil herniation, stent mal-positioning, or in-stent thrombosis. We retrospectively evaluated the efficacy and safety of additional rescue stenting (ARS) in telescoping fashion with Neuroform Atlas stent (NAS) during stent-assisted coiling of saccular aneurysms.

METHODS

We collected clinical and radiological data of patients with saccular aneurysms treated with ARS using NASs between March 2018 and December 2021. Y or X-stent-assisted coiling technique was excluded.

RESULTS

Eighteen unruptured and 5 ruptured aneurysms in 23 patients were treated with ARS using NASs. Sizes of aneurysms ranged from 2.0 mm to 10.0 mm (mean: 5.0 mm). Immediate angiographic results were complete occlusion in 11 aneurysms, residual neck in 4 aneurysms, and residual sac in 8 aneurysms. Peri-operative morbidity was 4.3 %. Nineteen of 23 patients underwent follow-up conventional angiography (mean, 9.9 months). Results showed progressive occlusion in 10 (52.6 %) cases and asymptomatic in-stent stenosis in 3 (15.8 %) cases. At the end of the observation period (mean, 17.4 months), all 18 patients without subarachnoid hemorrhage had excellent clinical outcomes (mRS of 0), except one (mRS of 1). Of five patients with subarachnoid hemorrhage, four had a favorable outcome (mRS of 0-1), while the other one was dependent (mRS of 4).

CONCLUSION

In this report on 23 patients, ARS with NASs for treating saccular aneurysms showed good technical safety with favorable clinical and angiographic outcomes. However, delayed in-stent stenosis was not uncommon. Thus, regular imaging follow-up is required.

Comparison of Solitaire and Neuroform Stenting for Coiling of Intracranial Bifurcation Aneurysms

PURPOSE

To compare the technical performance and outcomes of Solitaire and Neuroform stents for treatment of intracranial bifurcation aneurysms (IBAs).

METHODS

IBAs treated by stent-assisted coiling using a Solitaire or Neuroform stent between October 2010 and December 2019 were retrospectively evaluated. Patient demographics, aneurysm information, treatment technique, periprocedural and device-related complications, parent artery angle change, along with initial and follow-up angiographic results were analyzed.

RESULTS

One hundred twenty-one patients with 121 IBAs treated with Solitaire (n = 101) or Neuroform (n = 20) stent-assisted coiling were included. Aneurysm size, thrombotic and hemorrhagic complication rate, initial occlusion rate and in-stent stenosis between the two cohorts were not significantly different. Aneurysm location was significantly different between the two groups (p = 0.032). Jailing technique rate for coiling was significantly higher in the Solitaire than the Neuroform group (70.3% vs. 35.0%, p < 0.01). Follow-up DSA demonstrated a significantly lower recurrence rate for the Solitaire cohort (2.9% vs. 22.2%, p = 0.016). Parent artery angle changes, immediately post-operative and on follow-up were significantly greater in the Solitaire stent group (p < 0.05).

CONCLUSIONS

For intracranial bifurcation aneurysms, Solitaire stent-assisted coiling achieved a significantly lower recurrence rate and induced more favorable parent artery angular remodeling than Neuroform stenting.

Antiplatelet therapy discontinuation after stent-assisted coil embolization for intracranial aneurysms: a single-center, long-term, retrospective, observational study

OBJECTIVE

The protocol for antiplatelet therapy after stent-assisted coil embolization (SACE) for intracranial aneurysms is not well established. In particular, the indications for single antiplatelet therapy (SAPT) discontinuation remain controversial. The authors investigated the long-term outcomes of SAPT discontinuation after SACE among patients at a single institution.

METHODS

Patients who underwent SACE during the period from 2010 to 2020 and who were followed up for > 1 year were included in this study. The delayed ischemic and hemorrhagic complication rates were examined during follow-up. Moreover, the risk factors of antiplatelet therapy reduction or discontinuation and the outcomes of SAPT discontinuation were examined.

RESULTS

In total, 240 patients were included in the analysis. The average patient age was 60.3 years, and the average follow-up period was 46.7 months. Nine (3.8%) patients presented with symptomatic delayed ischemic complication, and 3 (1.3%) patients experienced a decline in modified Rankin Scale score. The stent configuration (T- or Y-stent) was the only risk factor associated with delayed ischemic complication (p < 0.001). SAPT was discontinued in 147 (71.7%) of 205 patients who were followed up for > 2 years, and no ischemic complications were observed.

CONCLUSIONS

It is safe to discontinue SAPT in patients without ischemic complications and with stable intraaneurysmal signals on MRA 2 years after SACE. The T- or Y-stent is a high-risk factor for delayed ischemic complications, and antiplatelet therapy reduction or discontinuation should be cautiously considered.

Endovascular treatment of ruptured basilar artery trunk aneurysm in the acute period: risk factors for periprocedural complications

OBJECTIVES

Endovascular treatment (EVT) has become a popular option for the treatment of basilar artery (BA) trunk aneurysms because microsurgery of these lesions is difficult due to narrow surgical fields and perforating arteries or cranial nerves in the brainstem. The purpose of this study is to report our experiences using EVT for ruptured BA trunk aneurysms in the acute period and to evaluate the risk factors for periprocedural complications.

METHODS

From October 2004 to December 2020, a total of 27 consecutive patients with ruptured BA trunk aneurysms were treated with EVT. All patients met the following criteria: presence of ruptured BA trunk aneurysms and treatment with EVT for those aneurysms within 72 hours of rupture. The incidence of and risk factors for periprocedural complications were evaluated retrospectively.

RESULTS

Among the 27 patients, periprocedural complications occurred in 4 patients (14.8%); mass effect inducing cranial neuropathy due to brainstem compression in 1 (3.7%) and brainstem infarction in 3 (11.1%). Hemorrhagic complications did not occur within 30 days. Subacute or delayed thromboembolic complications were not observed during the follow-up period. Large/giant aneurysm (odds ratio [OR], 6.417; 95% confidence interval [CI], 1.732-18.031; P = 0.045) and stent-assisted coiling (OR, 4.145; 95% CI, 1.018-14.212; P = 0.031) remained independent risk factors for periprocedural complications based on multiple logistic regression analysis.

CONCLUSIONS

When performing stent-assisted coiling for ruptured large/giant BA trunk aneurysms, awareness of and caution regarding periprocedural complications, such as brainstem infarction caused by thromboembolism or brainstem compression due to mass effect, are necessary.

Is it safe to discontinue antiplatelet medication after stent-assisted coil embolization? If so, when is the best time?

PURPOSE

Antiplatelet maintenance after stent-assisted coil embolization (SACE) is generally considered essential to avoid post-procedural thromboembolic complications. However, there is still debate as to whether it is safe to discontinue antiplatelet drugs after SACE or when is the best time to do so. We investigate herein the clinical outcomes experienced by patients who discontinue antiplatelet agents after SACE.

METHODS

From a prospective database, we retrieved the data for 120 consecutive patients (harboring 130 aneurysms) in whom antiplatelet agents were discontinued after SACE between January 2010 and December 2019. We defined thromboembolic complications associated with discontinuation as neurologic or radiographic ischemia that occurred within 6 months of discontinuation of antiplatelet agents; the lesion was required to be correlated with the stented artery.

RESULTS

The mean time of discontinuation of antiplatelet medication was 31.4 ± 18.3 months after SACE (median, 26 months). The majority of patients stopped antiplatelet medication between 18 and 36 months after SACE (74 patients, 61.6%). Laser-cut closed-cell stent was most commonly applied in 91 aneurysms (70.0%), followed by braided closed-cell (n=29; 22.3 %) and laser-cut open-cell stent 10 (7.7 %). No patients experienced cerebral ischemia related to discontinuation of antiplatelet medication.

CONCLUSION

Our preliminary study suggests that it may be safe to discontinue antiplatelet medication after SACE in patients at low risk for ischemia. The optimal time to discontinue might be around 18 to 36 months after SACE. Large cohort-based studies or randomized clinical trials are warranted to confirm these results.

Safety and effectiveness of double microcatheter technique in the treatment of ruptured aneurysms of anterior cerebral circulation

Objective

To evaluate the safety and effectiveness of the double microcatheter technique in the treatment of ruptured aneurysms of the anterior cerebral circulation.

Methods

Between 2012 and 2019, 113 patients with ruptured aneurysms of the anterior cerebral circulation were treated using the double microcatheter technique. Clinical records, angiographic results, and procedure-related complications were reviewed. Clinical and angiographic follow-up was performed.

Results

Complete occlusion, neck remnant, and partial occlusion were, respectively, recorded in 56.6, 38.9, and 4.4% of the total cases. For all patients, the incidence of intraoperative complications was 5.3% (6/113), and the overall rate of morbidity was 10.6% (12/113). Before discharge, three patients (2.7%) died. There was no procedure-related mortality. At discharge, favorable outcomes were observed in 79.6% (90/113) of the patients. High Hunt-Hess grades and receiving a craniotomy or external ventricular drainage were risk factors for clinical outcomes at discharge. Clinical follow-up was performed in 91 patients at a mean interval of 14.07 ± 11.68 months. At follow-up, favorable outcomes were observed in 92.3% (84/91) of the patients. Angiographic follow-up was performed in 66 patients at an average of 11.53 ± 11.13 months. The recurrence rate was 37.9%. Of these patients, 13 (19.7%) received retreatment.

Conclusion

The double microcatheter technique can be performed in ruptured aneurysms with high technical success and low morbidity/mortality. However, recurrence remains a problem, and patients should be followed up regularly.

Efficacy of pipeline embolization device vs. traditional coils in embolization of intracranial aneurysms: A systematic review and meta-analysis

Introduction

In recent years, the Pipeline embolization device (PED) has been widely used in the embolization of intracranial aneurysms, but there are some inconsistent findings on whether its efficacy and safety are superior to those of traditional coils embolization (coils alone, stent-assisted coils and balloon-assisted coils). The purpose of this meta-analysis was to evaluate the safety and efficacy of PED in intracranial aneurysm embolization by comparing with traditional coils.

Methods

We systematically searched PubMed, Embase, Web of Science, and The Cochrane Library databases for randomized controlled trials and observational studies (case-control studies and cohort studies) comparing the efficacy of PED with traditional coils in intracranial aneurysm embolization published before April 1, 2022. The endpoints observed in this meta-analysis were procedure-related intracranial hemorrhage, procedure-related intracranial ischemia, other procedure-related complications (e.g., aneurysm rupture, neurological impairment, etc.), retreatment rate, complete occlusion (100%) of the aneurysm at the last follow-up, and favorable functional outcome (MRS ≤ 2).

Results

A total of 10 studies with a total of 1,400 patients (PED group: 576 and Traditional coils: 824) were included in this meta-analysis. A comprehensive analysis of the included literature showed that the PED group had a higher rate of complete aneurysm occlusion [OR = 2.62, 95% Cl (1.94, 3.55), p &lt; 0.00001] and Lower re-treatment rate [OR = 0.20, 95% Cl (0.12, 0.34 p &lt; 0.00001)] compared with the traditional coil embolization group at the last follow-up. In terms of procedure-related intracranial hemorrhage [OR = 3.04, 95% Cl (1.08, 8.57), p = 0.04] and other procedure-related complications [OR = 2.91, 95% Cl (1.48, 5.57), p = 0.002], the incidence of PED was higher than that of the traditional coil embolization group. Moreover, in terms of favorable functional outcome [OR = 0.4, 95% Cl (0.22, 0.71), p = 0.002] of patients at the last follow-up, the PED group was lower than the traditional coil embolization group. There was no statistically significant between the two groups in terms of surgery-related intracranial ischemia complications [OR = 0.88, 95% Cl (0.47, 1.64), p = 0.68].

Conclusion

PED had higher rates of complete aneurysm occlusion and lower rates of aneurysm retreatment compared with traditional coils, but traditional coils was superior to the PED group in terms of procedure-related intracranial hemorrhage complication and other procedure-related complications (aneurysm rupture, neurological impairment), and favorable functional outcome (mRS ≤ 2). This result still needs to be further confirmed by additional large-sample, multicenter, prospective randomized controlled trials.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/, identifier: CRD42022325673.

Comparison of the Pipeline embolisation device alone or combined with coiling for treatment of different sizes of intracranial aneurysms

Objectives

The aim of this study was to compare complications and outcomes between intracranial aneurysms treated with the Pipeline embolisation device (PED) alone or with PED combined with coiling for different-sized aneurysms.

Method

Patients with aneurysms treated by PED were collected from the PED in China postmarket multicentre registry study. We performed a propensity match analysis to compare the efficacy and safety between PED alone and PED combined with coiling treatment, and then aneurysms were organised into three groups based on their size: small (≤7 mm), medium (≤15 mm to >7 mm) and large/giant (>15 mm). Complications and aneurysm occlusion rates in the aneurysm size groups were compared between PED alone and PED combined with coiling patients.

Result

A total of 1171 patients with 1322 aneurysms were included. All patients received clinical follow-up, while angiographic follow-up was available in 967 aneurysms. For small aneurysms, there was no difference in the aneurysm occlusion rate between two groups (79.1% vs 88.4%, respectively), while there was a significant increase in the ischaemic complication rate (8.3% vs 19.3%, respectively, p=0.0001). For medium and large/giant saccular aneurysms, PED combined with coiling significantly improved the occlusion rate (medium aneurysms: 74.7% vs 88.8%, respectively, p<0.0001; large/giant saccular aneurysms: 72.9% vs 86.9%, respectively, p=0.018), while there were no differences in the total complication rate. For large/giant non-saccular aneurysms, two groups showed no differences.

Conclusion

Use of the PED with adjunctive coils can significantly improve the occlusion rate of medium aneurysms, without increasing the total complication rate.

Ophthalmic Segment Aneurysms: Surgical Treatment and Outcomes

Background  Surgical treatment of ophthalmic segment aneurysms (OSAs) remain challenging because of complex anatomy surrounding the aneurysm and entails extensive drilling of anterior clinoid process to define proximal neck of the aneurysm and carotid exposure in the neck for proximal control. Materials and Methods  Authors present a retrospective analysis of 36 aneurysms in 35 patients with OSAs operated surgically by first author. Surgical clipping was done for the aneurysms as primary modality of treatment along with wrapping and trapping as required. Results  Commonest age group was 40 to 60 years with female preponderance of 3:1. Maximum (23) patients presented with subarachnoid hemorrhage (WFNS Gr 1), followed by asymptomatic patients (six). There were 18 small, 14 large, and four giant aneurysms, 15 dorsal wall, 17 ventral wall, three proximal posterior wall, and one blister aneurysm. Good outcome, as measured by Glasgow Outcome Score (GOS) was achieved in 29 patients. Conclusion  OSAs are technically demanding aneurysms, but with due diligence to surgical principles, good outcomes may be obtained.

Correlation Between Vascular Geometry Changes and Long-Term Outcomes After Enterprise Stent Deployment for Intracranial Aneurysms Located on Small Arteries

BACKGROUND

Enterprise stents are widely used for intracranial aneurysms located on small arteries (<2.5 mm in diameter) and change the geometry of parent arteries. The purpose of this study was to investigate the correlation between vascular geometry changes and long-term outcomes.

METHODS

Between May 2013 and 2018, 1065 consecutive intracranial aneurysms were treated with Enterprise stents at our institution. After inclusion and exclusion criteria were applied, 377 aneurysms with >6 months of digital subtraction angiography follow-up were evaluated. The cohort comprised 101 aneurysms located on small parent arteries. After stent-assisted coiling, the vascular geometry parameters of small parent arteries were compared to explore their correlation with procedural complications, delayed stent migration, and recanalization.

RESULTS

The rate of delayed aneurysm occlusion in patients with initial efferent artery diameter (De) <2.5 mm was significantly higher than in patients with De >2.5 mm (62.2% vs. 40.2%; P = 0.032). At follow-up, vascular geometry parameters significantly increased (P < 0.001). In multivariate analyses, larger aneurysms and initial parent artery angle (α) <90° were independent predictors of procedural complications and discrepancy in vessel size (ΔD) >0.5 mm was an independent predictor of delayed stent migration. Larger aneurysms and follow-up angle change (ΔAngle) <30° were independent predictors for recanalization of aneurysms located on small arteries.

CONCLUSIONS

Enterprise stent-assisted coiling of intracranial aneurysms located on small arteries is safe and effective. Our study found that Enterprise deployment in small arteries had a low procedural complication rate and high stent tolerance. Vascular geometry changes play an important role in aneurysm recanalization.

Emergent carotid artery stenting for cervical internal carotid artery injury during carotid endarterectomy: A case report

Background:

Carotid endarterectomy (CEA) has been the standard preventive procedure for cerebral infarction due to cervical internal carotid artery stenosis, and internal shunt insertion during CEA is widely accepted. However, troubleshooting knowledge is essential because potentially life-threatening complications can occur. Herein, we report a case of cervical internal carotid artery injury caused by the insertion of a shunt device during CEA.

Case Description:

A 78-year-old man with a history of hypertension, diabetes, and hyperuricemia developed temporary left hemiplegia. A former physician had diagnosed the patient with a transient cerebral ischemic attack. The patient’s medical history was significant for the right internal carotid artery stenosis, which was severe due to a vulnerable plaque. We performed CEA to remove the plaque; however, there was active bleeding in the distal carotid artery of the cervical region after we removed the shunt tube. Hemostasis was achieved through compression using a cotton piece. Intraoperative digital subtraction angiography (DSA) revealed severe stenosis at the internal carotid artery distal to the injury site due to hematoma compression. The patient underwent urgent carotid artery stenting and had two carotid artery stents superimposed on the injury site. On DSA, extravascular pooling of contrast media decreased on postoperative day (POD) 1 and then disappeared on POD 14. The patient was discharged home without sequela on POD 21.

Conclusion:

In the case of cervical internal carotid artery injury during CEA, hemostasis can be achieved by superimposing a carotid artery stent on the injury site, which is considered an acceptable troubleshooting technique.

Stent-assisted coiling of cerebral aneurysms: Head to head comparison between the Neuroform Atlas and EZ stents

BACKGROUND

The Neuroform Atlas stent is thought to have features allowing for an improved stent delivery system. We aimed to provide a comparison of the Atlas and Neuroform EZ stents in patients treated with stent-assisted coiling.

METHODS

Seventy-seven aneurysms treated with the Atlas stent and 77 aneurysms with similar characteristics treated with the EZ stent were retrospectively compared. Outcomes included angiographic occlusion per the Raymond-Roy (RR) scale, recanalization, retreatment and procedural complications.

RESULTS

With the Atlas stent, technical success was 100% and immediate RR1 occlusion was 81.8%. Follow-up RR1 was achieved in 83.7%. The recanalization rate was 7% and the retreatment rate was 4.6%. The complication rate was 6.5% (new neurological deficit in 1.3%). With the EZ stent, technical success was 96%, immediate RR1 occlusion was 67.6% and follow-up RR1 was 67.6%. The recanalization rate was 12.7% and the retreatment rate was 14.1%. The complication rate was 10.4% (new neurological deficit in 2.6%). The rate of immediate RR1 occlusion was significantly higher with the Atlas stent (p = 0.03), and the rate of follow-up RR1 was nonsignificantly higher with the Atlas stent (p = 0.08). The retreatment rate was significantly lower with the Atlas stent (p = 0.009). There were no significant differences in the rates of recanalization (p = 0.5) and complications (p = 0.6).

CONCLUSIONS

Stent-assisted coiling with the Atlas stent is safe and effective and shows better immediate results as compared to the EZ stent, with improved overall follow-up outcomes.

Wingspan Stenting for Symptomatic Severe In-Stent Stenosis of a Closed-Cell Stent after Stent-Assisted Coiling of a Ruptured Intracranial Aneurysm

We report the 3-year follow-up result of Wingspan intracranial stenting for symptomatic severe in-stent stenosis after stent-assisted coiling (SAC) for a ruptured left distal internal carotid artery (ICA) aneurysm. A middle-aged male patient visited our hospital for in-stent stenosis of a stent that was placed to treat a ruptured ICA aneurysm. Routine follow-up cerebral angiography, 1 year after SAC, showed in-stent stenosis around the distal markers of the inserted stent at the left M1 proximal segment. Six months later, he developed right dysesthesia. We performed intracranial stenting with Wingspan stent for the in-stent stenosis. Follow-up digital subtraction angiography performed 1 year after the Wingspan stenting showed good patency of the ICA and middle cerebral artery flow without evidence of restenosis. At 3-year follow-up, magnetic resonance angiography showed sufficient middle cerebral artery flow although the stenting segment could not be visualized clearly. Wingspan stenting might be a feasible option in patients with iatrogenic intracranial stenosis resulting from in-stent stenosis who experience the progression of intracranial stenosis with manifestation of neurological symptoms despite dual anti-platelet therapy.

Bleeding from an Unruptured Cerebral Aneurysm following the Local Intra-arterial Administration of Urokinase: A Case Report

A 57-year-old woman with a wide-necked anterior communicating artery (Acom) aneurysm underwent stent-assisted coiling (SAC) due to aneurysm enlargement. Dual antiplatelet therapy was initiated 7 days before the operation, and systemic heparinization was performed while maintaining an activated clotting time (ACT) of approximately 300 s during the procedure. SAC was performed using a laser-cut closed-cell stent and bare platinum coils. At the end of the procedure, the Acom and right anterior cerebral artery (ACA) were occluded by in-stent thrombosis. Following local intra-arterial administration of 480000 U of urokinase, the Acom and right ACA were recanalized, accompanied by extravasation around the Acom aneurysm. A computed tomography (CT) scan revealed a right frontal hematoma, which did not enlarge after the administration of protamine sulfate. The hematoma disappeared spontaneously, and the patient recovered without any neurological deficits. Local administration of urokinase is an effective treatment for in-stent thrombosis. However, because the devices for SAC may cause mechanical injuries to the aneurysms, urokinase should be used cautiously for cerebral aneurysms, even if unruptured.

Two Patients with Large Aneurysms in Whom Coil Embolization with Overlapping LVIS Stents Was Performed

Objective

We report two patients with unruptured large aneurysms treated by overlapping stent-assisted coil embolization using low-profile visualized intraluminal support (LVIS) stents.

Case Presentation

Case 1: An 80-year-old woman presented with abducens nerve palsy due to an internal carotid artery aneurysm. Case 2: A 75-year-old man presented with a partially thrombosed fusiform aneurysm in the vertebral artery (VA). Both patients were treated by overlapping LVIS stent-assisted coil embolization (overlapping LSACE). Digital subtraction angiography (DSA) a few months after embolization demonstrated complete occlusion of the aneurysm, although immediate angiography revealed dome filling.

Conclusion

Overlapping LSACE may be an effective treatment method for aneurysms that are difficult to treat by standard SACE and result in better flow-diverting effects.

Comparison of stent-assisted and no-stent coil embolization for safety and effectiveness in the treatment of ruptured intracranial aneurysms

OBJECTIVE

The safety of the stent-assisted coil embolization (SAC) technique for acutely ruptured aneurysms has not been established yet. SAC is believed to be associated with a high risk of thromboembolic and hemorrhagic complications in acute subarachnoid hemorrhage (SAH). The aim of this study was to evaluate the safety and efficacy of the SAC technique in the setting of acutely ruptured aneurysm.

METHODS

A total of 102 patients who received endovascular treatment for acute SAH between January 2011 and December 2017 were enrolled. The SAC technique was performed in 38 of these patients, whereas the no-stent coil embolization (NSC) technique was performed in 64. The safety and efficacy of the SAC technique in acute SAH was evaluated as compared with the NSC technique by retrospective analysis of radiological and clinical outcomes.

RESULTS

There were no significant differences in clinical or angiographic outcomes between the SAC and NSC techniques in patients with acute SAH. The rate of ventriculostomy-related hemorrhagic complications was higher in the SAC group than that in the NSC group (63.6% vs 12.5%; OR 12.25, 95% CI 1.78-83.94, p = 0.01). However, all these complications were asymptomatic and so small that they were only able to be diagnosed with imaging.

CONCLUSIONS

Ruptured wide-necked aneurysms could be effectively and safely treated with the SAC technique, which showed clinical and angiographic outcomes similar to those of the NSC technique. Hence, the SAC technique with dual-antiplatelet drugs may be a viable option even in acute SAH.

Strategies to Prevent Ischemic Complications after Stent-assisted Coil Embolization of Cerebral Aneurysms

Objective

There have been no delayed ischemic complications related to stent-assisted coil embolization (SACE) of cerebral aneurysms at our institution. We demonstrate our strategies for stent placement and postoperative management of antiplatelet therapy to reduce the risk of ischemic complications.

Methods

We analyzed 57 cases of SACE retrospectively. In the procedure, an appropriate stent was selected and placed to fit the arterial wall without impeding on small arterial branches. Two different antiplatelet drugs, including clopidogrel, were used. Six to twelve months after surgery, follow-up angiography was performed to assess the safety of terminating antiplatelet therapy. In cases in which antiplatelet therapy was tapered, the two antiplatelet drugs were switched to clopidogrel alone, and it was subsequently tapered and finally discontinued.

Results

There were 49 cases of SACE in which postoperative antiplatelet therapy was tapered. Among these cases, antiplatelet therapy was discontinued in 35 cases. The mean duration of dual antiplatelet therapy was 10.6 ± 2.8 months, and the mean duration of total antiplatelet therapy was 15.0 ± 2.1 months. Three patients developed SACE-related ischemic stroke, which developed in the early phase after surgery in all.

Conclusion

Antiplatelet therapy can safely be terminated in most cases of SACE. In order to reduce the risk of ischemic complications, stent selection, stent placement, and management of antiplatelet therapy should be performed appropriately. Furthermore, careful follow-up should be continued even after the termination of antiplatelet therapy.

Recent advances in stent-assisted coiling of cerebral aneurysms

INTRODUCTION

Stent-assisted coiling (SAC) of intracranial aneurysms paved the way for endovascular coiling of wide-neck and bifurcation aneurysms, improving rates of aneurysm obliteration and recurrence. In this review, we provide a comprehensive review of the most recent advances related to stent-assisted coiling of intracranial aneurysm.

AREAS COVERED

The authors have made an attempt to cover the inception, applications, and limitations of SAC of intracranial aneurysms. Special focus is given to 1) the current and recently introduced SAC techniques, 2) most recent advances in device technology, and 3) outcome data for the discussed techniques and devices. The authors also discuss the potential future direction of SAC.

EXPERT OPINION

technical refinements in the field of SAC should continue to focus on device development and addressing the limitations of SAC, namely aneurysm recurrence and need of antiplatelet agents. Although the recurrence rate of SAC has not been shown to be inferior to flow diverters, the use of intrasaccular and intravascular flow diverters are likely to expand in the future at the expense of SAC.

Predictors of hospital-associated complications prolonging ICU stay in patients with low-grade aneurysmal subarachnoid hemorrhage

OBJECTIVE

The authors sought to determine the predictors of late neurological and hospital-acquired medical complications (HACs) in patients with low-grade aneurysmal subarachnoid hemorrhage (aSAH).

METHODS

The authors conducted a retrospective study of 424 patients with low-grade aSAH admitted to their institution from 2008 to 2015. Data collected included patient comorbidities, Hunt and Hess (HH) grade, ICU length of stay (LOS), and complications. A logistic regression analysis was performed to determine the predictors for neurological and hospital-associated complications.

RESULTS

Out of 424 patients, 50 (11.8%) developed neurological complications after the first week, with a mean ICU stay of 16.3 ± 6.5 days. Of the remaining 374 patients without late neurological complications, 83 (22.2%) developed late HACs with a mean LOS of 15.1 ± 7.6 days, while those without medical complications stayed 11.8 ± 6.2 days (p = 0.001). Of the 83 patients, 55 (66.3%) did not have any HACs in the first week. Smoking (p = 0.062), history of cardiac disease (p = 0.043), HH grade III (p = 0.012), intraventricular hemorrhage (IVH) (p = 0.012), external ventricular drain (EVD) placement (p = 0.002), and early pneumonia/urinary tract infection (UTI)/deep vein thrombosis (DVT) (p = 0.001) were independently associated with late HACs. Logistic regression showed early pneumonia/UTI/DVT (p = 0.026) and increased HH grade (p = 0.057) to be significant risk factors for late medical complications.

CONCLUSIONS

While an extended ICU admission allows closer monitoring, low-grade aSAH patients develop HACs despite being at low risk for neurological complications. The characteristics of low-grade aSAH patients who would benefit from early discharge are reported in detail.

Impact of hospital-acquired complications in long-term clinical outcomes after subarachnoid hemorrhage

OBJECTIVE

Patients with subarachnoid hemorrhage (SAH) usually have prolonged hospitalizations due to the need to closely monitor their neurological status. Therefore, these patients have higher risk of experiencing hospital-acquired complications (HACs), which can complicate their clinical course and recovery. However, there is no evidence on the impact of HACs of long-term clinical outcomes. We aimed to identify if HACs are independent risk factors for poor clinical outcomes at 12-18 months of follow-up.

PATIENTS AND METHODS

Retrospective analysis of 323 patients with SAH diagnosis from 2013 until June 2018. We collected patient-related factors (age, sex, body mass index (BMI), ethnicity), comorbidities (hypertension, smoke status, diabetes, coronary heart diseases, prothrombotic diseases and hypercholesterolemia), clinical variables (Hunt-Hess grade, modified Fisher grade, treatment, delayed cerebral ischemia), aneurysm characteristics (location, size) and HACs (pneumonia, deep vein thrombosis (DVT), urinary tract infection (UTI), external ventricular drainage (EVD) infections, sepsis, hyponatremia and acute respiratory distress syndrome). Poor outcomes were defined as mRS ≥ 3.

RESULTS

204 patients were included in the primary analysis. 82 (40.2%) experienced one or more HACs during their hospital course. Patients that developed HACs have significantly increased ICU (12.1 ± 6.6 vs 24.3 ± 23.6, p < .001) and hospital (18.7 ± 14.2 vs 35.3 ± 26.3, p < .001) length of stays. Moreover, patients with HACs had significant higher rates of delayed cerebral ischemia, non-routine discharge and poor outcomes at 90 days. 177 patients had complete follow-ups at 12-18 months, HACs were independent risk factors for poor functional outcomes at 12-18 months after adjusting for demographic, comorbidities and clinical variables [OR = 3.205, 95% CI 1.231-8.347, p < 0.001].

CONCLUSIONS

HACs are an independent risk factor of sustaining poor clinical outcomes 12-18 months after a SAH. Furthermore, HACs are significantly related with the occurrence of DCI, with non-routine discharge and 90-day poor functional outcomes.

Comparative Outcome Analysis of Enterprise and Neuroform Stent-Assisted Coiling of Cerebral Aneurysms: A Review of the Literature

Introduction

One of the popular treatment strategies for complex cerebral aneurysms with wide necks or low dome-to-neck ratios is stent-assisted coiling. The most widely used intracranial stents for stent-assisted coiling are Neuroform (NF) and Enterprise (EP) stents. The purposes of this study are to review the recent literature of the past 5 years to compare outcomes between the EP and NF stent-assist coiling systems so as to comment on the safety, efficacy, complications, and recurrence rate of stent-assisted coiling in general.

Methods

PubMed was used to search for all published literature of NF or EP stent-assisted coiling of unruptured cerebral aneurysms from January 2014 to August 2019 with the search terms of "Enterprise stent-assisted coiling," "Neuroform stent," and "Neuroform vs. Enterprise stent."

Results

Twenty two publications met the inclusion criteria which encompass 1764 patients and 1873 aneurysms. Out of these 1873 aneurysms, 1007 aneurysms were treated with EP stent and 866 aneurysms were treated with NF stent. The overall outcome was low rates of thromboembolic complications (4.37%) and intracranial hemorrhage (1.13%), low permanent morbidity (1.70%) and mortality (0.40%), and lower rate of recanalization (11%). Data analysis shows an overall higher rate of complication and recurrence of aneurysm and lower overall rate of aneurysmal occlusion in the patients where EP stent was used in comparison to NF stent. However, this difference was not statistically significant.

Conclusions

The review of two stent-assisted coiling devices using EP and NF stents including 1873 aneurysms in 1764 patients revealed that overall, it is safe and effective with comparable outcomes.

Low-Profile Laser-Cut Stents for Endovascular Treatment of Intracranial Aneurysms : Incidence, Clinical Presentation and Risk Factors of Thromboembolic Events

PURPOSE

Low-profile intracranial stents are characterized by a miniaturized design that enables deployment via a 0.0165″ or 0.017″ internal diameter microcatheter, which is typically intended for coil delivery. This study analyzed the incidence, clinical relevance and risk factors of thromboembolic events (TEE) occurring during low-profile stent-assisted coiling of intracranial aneurysms.

METHODS

This was a retrospective, multicenter analysis of consecutive patients who underwent stent-assisted aneurysm coiling (SAC) with the laser-cut Acandis Acclino and Neuroform Atlas stents. The study evaluated the incidence of symptomatic and asymptomatic TEEs and the impact on functional outcome. Risk factors for TEEs were determined by univariate and bivariate logistic regression analyses.

RESULTS

Among 131 procedures (mean patient age 56.5 ± 12.8 years, mean aneurysm size: 6.7 ± 3.9 mm) TEEs occurred in 14 cases (10.7%) of which 2 patients (1.5%) developed ischemic stroke, while the remaining TEEs remained asymptomatic. Multivariate analysis revealed Y‑stenting as potential risk factor for TEEs (odds ratio: 3.9, 95% confidence interval: 1.0-16.5; p = 0.08).

CONCLUSION

The use of SAC with low-profile intracranial stents is associated with a favorable safety profile; however, Y‑stenting may carry an increased risk of TEEs, which needs to be considered during treatment planning.

Y-Stenting Versus PulseRider-Assisted Coiling in the Treatment of Wide-Neck Bifurcation Aneurysms: Role of Anatomical Features on Midterm Results

BACKGROUND

Y-stenting is an effective but challenging approach for wide-neck aneurysms. PulseRider (PR) (Pulsar/Cerenovus) is a new device designed to provide scaffolding during coiling but has never been compared with other techniques.

OBJECTIVE

To compare the immediate and 6-mo results of Y-stenting vs PR assisted coiling.

METHODS

A total of 105 consecutive patients were retrospectively divided into 2 groups (73 Y-stenting and 32 PR). All underwent angiographic 6-mo follow-up. We evaluated if some anatomical features could influence treatment results.

RESULTS

The groups were homogeneous. Immediate adequate occlusions as well as complication rates were similar in Y-stenting and PR group (94.5% vs 96.9% and 8.2% vs 6.2%, respectively). At 6 mo, adequate occlusion was 93.1% after Y-stenting and 84.3% after PR (P = .28), complete occlusion was significantly higher after Y-stenting: 90.3% vs 62.5% (P = .0017). Occlusion grade worsening occurred in 6.9% of Y-stenting and 18.7% of PR patients (P = .09).

Neck size was associated with occlusion grade in both groups. Maximal aneurysm size was associated with occlusion grade in the PR group (P = .023) but not in the Y-stenting group (P = .06). After PR, 6-mo occlusion rate was higher in small (&lt; 10 mm) than in large aneurysms (P = .0094); this was not observed after Y-stenting (P = .54).

Location did not significantly affect the mid-term occlusion rate in both the groups. After PR, occlusion was more stable in basilar than anterior or middle cerebral artery aneurysms.

CONCLUSION

Y-stenting and PR are both effective with similar immediate and mid-term results. However, treatment stability seems higher after Y-stenting. Aneurysm size seems to negatively affect PR results.

Long-term Angiographic Results of the Low-profile Acandis Acclino Stent for Treatment of Intracranial Aneurysms : A Multicenter Study

PURPOSE

The low-profile Acandis Acclino is a self-expandable nitinol microstent for stent-assisted coiling of intracranial aneurysms. This article reports long-term clinical and angiographic outcome in a multicenter setting.

METHODS

In this study 98 consecutive patients (mean age 55.4 ± 13.5 years) were treated with the Acclino for 98 aneurysms (28 unruptured, 20 recurrent, 50 ruptured) at 3 German tertiary care centers within a 6-year period. The technical success, complications, clinical outcome and angiographic results were retrospectively analyzed.

RESULTS

The technical success rate was 100% with immediate complete occlusion achieved in 89.8% of the patients. Among 65 patients (66.3%) available for a 6‑month follow-up, complete and near-complete occlusion rates were 92.3% and 98.5%, respectively. In 38 patients (38.8%) with long-term follow-up (mean: 21 months), complete and near-complete occlusion were achieved in 81.2% and 89.5%, respectively. Aneurysm recurrence between mid-term and long-term follow-up was observed in 14.3%. The retreatment rate was 11.3%. There were three thromboembolic events (3.1%), of which one resulted in ischemic stroke (1.0%). For unruptured aneurysms, the procedural and device-related morbidity rates were 2.1% and 0%, respectively.

CONCLUSION

In the present study, the Acclino was associated with a low risk of thromboembolic complications and high aneurysm occlusion rates at long-term follow-up. Due to incomplete angiographic follow-up in this series, prospective studies will be necessary to confirm the results.

Safety and Long-term Efficacy of Stent-assisted Coiling for the Treatment of Complex Posterior Cerebral Artery Aneurysms

OBJECTIVE

To evaluate the safety and long-term efficacy of stent-assisted coiling for the treatment of complex posterior cerebral artery (PCA) aneurysms.

METHODS

Angiographic and clinical data of 23 patients harboring 23 complex PCA aneurysms treated with stent-assisted coiling from March 2010 to March 2017 were retrospectively reviewed.

RESULTS

In this study 8 (34.8%) aneurysms were located at the P1 segment, 7 (30.4%) at the junction of P1 and P2 segments (P1-2), and 8 (34.8%) at the P2 segment. The aneurysms were ruptured in 7 cases (30.4%). Thirteen were dissecting in nature, while the other 10 were classical saccular aneurysms. Of the patients, 5 (21.7%) had of history of recent head trauma, immediate angiographic results were Raymond class I in 5 (21.7%) cases, Raymond class II in 8 (34.8%), and Raymond class III in 10 (43.5%). Perioperative complications occurred in one case with occlusion of the PA due to acute in-stent thrombosis without any neurologic deficit at discharge. The last angiographic follow-up (mean 18.7 months) results demonstrated complete aneurysmal occlusion in 20 (87.0%) cases, PA occlusion in 1 (4.3%) and recurrence in 2 (8.7%). Of the two patients with aneurysm recurrence, one was treated by PA occlusion, and the other was treated with two overlapping stents. Clinical follow-up (mean 58.3 months) was available for all 23 patients, 22 (95.7%) patients had good neurologic outcomes (mRS score 0-2), and 1 (4.3%) patient died 7 months after the procedure for unknown reasons.

CONCLUSION

Stent-assisted coiling for the treatment of complex PCA aneurysms is safe and durable with a relatively low rate of complication and a relatively high rate of complete occlusion at long-term follow-up and is a promising alternative strategy for the reconstruction of the PCA.

Pipeline Endovascular Device vs Stent-Assisted Coiling in Small Unruptured Aneurysms: A Cost-Effectiveness Analysis

BACKGROUND

Both stent-assisted coiling (SAC) and flow diversion with the Pipeline Embolization device (PED; Medtronic Inc) have been shown to be safe and clinically effective for treatment of small (<10 mm) unruptured aneurysms. However, the economic impact of these different techniques has not been established.

OBJECTIVE

To analyze the cost-effectiveness between stent-assisted coiling and flow diversion using PED, including procedural costs, long-term outcomes, and aneurysm recurrence.

METHODS

A decision-analytical study was performed with Markov modeling methods to simulate patients undergoing SAC or PED for treatment for unruptured aneurysms of sizes 5 and 7 mm. Input probabilities were derived from prior literature, and 1-way, 2-way, and probabilistic sensitivity analyses (PSA) were performed.

RESULTS

In base case calculation and PSA, PED was the dominant strategy for both the size groups, with and without consideration of indirect costs. One-way sensitivity analyses show that the conclusion remained robust when varying the retreatment rate of SAC from 0% to 50%, and only changes when the retreatment rate of PED > 49%. PED remained the more cost-effective strategy when the morbidity and mortality of PED increased by <55% and when those of SAC decreased by <37%. SAC only became cost-effective when the total cost of PED is >$73000 more expensive than the total cost of SAC.

CONCLUSION

With increasing use of PED for treatment of small unruptured anterior circulation aneurysms, our study indicates that PED is cost-effective relative to stent coiling irrespective of aneurysm size. This is due to lower aneurysm recurrence rate, as well as better health outcomes.

Exploring the Feasibility of Pipeline Embolization Device Compared With Stent-Assisted Coiling to Treat Non-saccular, Unruptured, Intradural Vertebral Artery Aneurysms

Object: The pipeline embolization device (PED) has been used to treat non-saccular, unruptured, intradural vertebral artery aneurysms at some institutions. However, there is an absence of large controlled studies validating the feasibility of this treatment. This study aimed to explore the therapeutic feasibility of PED by comparing PED treatment with controlled stent-assisted coiling (SAC).

Materials and Methods: Thirty-two PED procedures were matched in a 1:2 manner with 64 SAC procedures based on patient age, sex, aneurysm size, and aneurysm location. Technical factors, procedural complications, angiographic results, and clinical outcomes were analyzed and compared.

Results: There was no statistically significant difference in technical factors and procedural complications between the two groups (PED vs. SAC, 9.4 vs. 4.7%, P = 0.397). In multivariate analysis, smoking and therapeutic modality were identified as independent predictors of occlusion. Smoking was a risk factor for aneurysm obliteration [hazard ratio (HR) 0.53; 95% confidence interval (CI), 0.31–0.89; P = 0.018]. Aneurysms treated with PED were more likely to achieve obliteration over time compared with aneurysms treated with SAC (HR 2.97; 95% CI, 1.79–4.93; P < 0.001). The rate of favorable clinical outcomes (modified Rankin Scale (mRS), 0–2) was similar between the two groups (PED vs. SAC, 100 vs. 96.9%, P = 0.551). In the SAC group, one patient had neurological deficit with an mRS of four at the latest follow-up. There was no mortality in either group.

Conclusions: The PED and SAC groups showed similar technical factors, procedural complications, angiographic results, and favorable clinical outcomes. Aneurysms treated with PED were more prone to obliteration over time than aneurysms treated with SAC. These outcomes suggest, based on short-term follow-up, PED is a safe and feasible strategy for the treatment of non-saccular, unruptured, intradural vertebral artery aneurysms.

Endovascular Metal Devices for the Treatment of Cerebrovascular Diseases

Cerebrovascular disease involves various medical disorders that obstruct brain blood vessels or deteriorate cerebral circulation, resulting in ischemic or hemorrhagic stroke. Nowadays, platinum coils with or without biological modification have become routine embolization devices to reduce the risk of cerebral aneurysm bleeding. Additionally, many intracranial stents, flow diverters, and stent retrievers have been invented with uniquely designed structures. To accelerate the translation of these devices into clinical usage, an in-depth understanding of the mechanical and material performance of these metal-based devices is critical. However, considering the more distal location and tortuous anatomic characteristics of cerebral arteries, present devices still risk failing to arrive at target lesions. Consequently, more flexible endovascular devices and novel designs are under urgent demand to overcome the deficiencies of existing devices. Herein, the pros and cons of the current structural designs are discussed when these devices are applied to the treatment of diseases ranging broadly from hemorrhages to ischemic strokes, in order to encourage further development of such kind of devices and investigation of their use in the clinic. Moreover, novel biodegradable materials and drug elution techniques, and the design, safety, and efficacy of personalized devices for further clinical applications in cerebral vasculature are discussed.

Treatment of broad-based intracranial aneurysms with low profile braided stents: a single center analysis of 101 patients

BACKGROUND AND PURPOSE

Low profile braided stents have facilitated the endovascular treatment of broad-based intracranial aneurysms.

METHODS

Between 2013 and June 2018, we attempted 104 Leo baby stent placements in 101 patients. Locations were the anterior communicating artery (AcomA) (37 aneurysms, 35.6%), middle cerebral artery (MCA) bifurcation (29 aneurysms, 27.9%) and basilar artery (23aneurysms, 22.1%). Mean neck size was 4.9 mm (2.2-8.2). 60 aneurysms were incidental, 31 of 37 recurrent aneurysms had ruptured before.

RESULTS

Stent deployment was successful in 89.4% of cases. Common reasons for failure were inability to access the parent artery (n=5) or to deploy the stent across the aneurysm neck (n=4). Two patients had poor outcomes within 24 hours. One patient developed a brain hemorrhage caused by guide wire perforation (MRS 5), the other an early thrombotic stent occlusion (MRS 4). No patient died. Nine (8.7%) patients experienced transient neurological deficits with ischemic lesions on diffusion weighted imaging (DWI). Initially Raymond-Roy class 1 occlusion was achieved in 23 aneurysms (24.7%), class 2 occlusion in 40 (43%), class 3a occlusion in 14 (15.0%), and 3b occlusion in 16 aneurysms (17.2%). Follow-up imaging in 87 patients showed stable or improved occlusion grades in 76%. Six patients required retreatment while the rest were managed conservatively. Four delayed stent occlusions occurred in three patients, with severe morbidity in one patient (MRS 5). There were no aneurysm ruptures or deaths.

CONCLUSION

Stent assisted treatment of broad-based aneurysms with the Leo baby stent is safe and effective. The frequency of delayed thrombotic complications is low and similar to other stents.

Pipeline-assisted coiling versus pipeline in flow diversion treatment of intracranial aneurysms

BACKGROUND AND PURPOSE

Flow-diversion therapy (FDT) for large and complex intracranial aneurysms is effective and considered superior to primary coil embolization. Data evaluating common treatment with both FDT and coiling continues to emerge, but information on outcomes remains scarce. This study aims to examine further the efficiency and outcomes correlated with joint FDT using pipeline embolization device (PED) and coiling compared to PED-alone in treating intracranial aneurysms.

MATERIALS AND METHODS

Comparative review and analysis of aneurysm treatment with PED in 416 subjects were conducted. Joint modality, PED, and coiling were compared to PED-alone for aneurysm occlusion, recurrence, retreatment, thromboembolic or hemorrhagic events, and functional outcome using the modified Rankin Scale. Data on patient demographics, aneurysm characteristics, clinical and angiographic follow up, were also collected. Both univariate analysis and multivariate logistic regression modeling using mixed-effects were performed.

RESULTS

Total of 437 aneurysms were treated using PED of which 74 were managed with both PED and coiling. Average patient-age was 56 years, the majority were men (85%), an average aneurysm size was 9 mm, and the majority were saccular aneurysms (84%). Larger aneurysm size was associated with a poor outcome in patients with unruptured aneurysms (OR = 1.06). Adjusted regression analyses revealed no differences between treatment groups in thromboembolic or hemorrhagic events, aneurysm occlusion rate, residual flow on follow up angiography, or functional outcome.

CONCLUSIONS

Treatment of intracranial aneurysms with joint PED and coiling was safe with no increase in complications when compared to PED alone. Aneurysm occlusion rates and functional outcome with PED and coiling stays comparable to treatment with PED-alone.

Wide-neck bifurcation aneurysms of the middle cerebral artery and basilar apex treated by endovascular techniques: a multicentre, core lab adjudicated study evaluating safety and durability of occlusion (BRANCH)

Background and purpose

BRANCH (wide-neck bifurcation aneurysms of the middle cerebral artery and basilar apex treated by endovascular techniques) is a multicentre, retrospective study comparing core lab evaluation of angiographic outcomes with self-reported outcomes.

Materials and methods

Consecutive patients were enrolled from 10 US centres, aged between 18 and 85 with unruptured wide-neck middle cerebral artery (MCA) or basilar apex aneurysms treated endovascularly. Patient demographics, aneurysm morphology, procedural information, mortality and morbidity data and core lab and self-reported modified Raymond Roy (RR) outcomes were obtained.

Results

115 patients met inclusion criteria. Intervention-related mortality and significant morbidity rates were 1.7% (2/115) and 5.8% (6/103) respectively. Core lab adjudicated RR1 and 2 occlusion rates at follow-up were 30.6% and 32.4% respectively. The retreatment rate within the follow-up window was 10/115 (8.7%) and in stent stenosis at follow-up was 5/63 (7.9%). Self-reporting shows a statistically significant direction to angiographic RR one outcomes at follow-up compared with core lab evaluation, with OR 1.75 (95% CI 1.08 to 2.83).

Conclusion

Endovascular treatment of wide-neck MCA and basilar apex aneurysms resulted in a core lab adjudicated RR1 occlusion rate of 30.6%. Self-reported results at follow-up favour better angiographic outcomes, with OR 1.75 (95% CI 1.08 to 2.83). These data demonstrate the need for novel endovascular devices specifically designed to treat complex intracranial aneurysms, as well as the importance of core lab adjudication in assessing outcomes in such a trial.

Stent placement in patients with acute subarachnoid haemorrhage: when is it justified?

PURPOSE

Endovascular stents are widely used for the elective treatment of cerebral aneurysms. Acute stenting is performed in the management of dissections, pseudo-aneurysms, broad-based aneurysms or as a 'bail out' measure after coil migration. The purpose of this study is to review the safety of using stents in acute subarachnoid haemorrhage.

METHODS

The stent registry of our institution was reviewed for procedures in patients with acute subarachnoid haemorrhage. Imaging studies were reviewed on the hospital's PACS system and the patients' notes were retrieved to assess complications and clinical outcomes. Procedures were analysed according to the type of stent, treatment indication, antiplatelet regime, complications and outcomes.

RESULTS

Between 2008 and 2016, 51 stents were placed during 50 stenting procedures in 49 patients with acute subarachnoid haemorrhage. This included 24 patients with saccular aneurysms, 10 with blister aneurysms, 10 dissections and five fusiform aneurysms. Stents were deployed in 'bail out' situations on eight occasions. In six cases, flow-diverting stents were used. Eighteen patients (37%) in the cohort suffered a stroke. Nine patients (18%) suffered persistent clinical deficits as a result of the stenting procedure, all but one of which occurred within 24 h. Two patients had a transient ischaemic episode, and there was evidence of asymptomatic ischaemia on imaging in four cases (8%). Five patients died, three (6%) as a result of procedural complications. Twelve patients (25%) required a further embolisation procedure.

CONCLUSION

The use of stents in acute subarachnoid haemorrhage incurs a considerable complication risk and should be reserved for exceptional circumstances.

Parent Artery Reconstruction for Large or Giant Cerebral Aneurysms Using the Tubridge Flow Diverter: A Multicenter, Randomized, Controlled Clinical Trial (PARAT)

BACKGROUND AND PURPOSE

Although flow diverters have been reported with favorable clinical and angiographic outcomes in various literatures, randomized trials determining their true effectiveness and safety are still in lack. The Parent Artery Reconstruction for Large or Giant Cerebral Aneurysms Using the Tubridge Flow Diverter (PARAT) trial was designed to evaluate the safety and efficacy of the Tubridge flow diverter in the treatment of large or giant aneurysms in comparison with Enterprise stent-assisted coiling.

MATERIALS AND METHODS

This prospective, multicenter, randomized trial was conducted at 12 hospitals throughout China. Enrolled adults with unruptured large/giant intracranial aneurysms were randomly assigned (1:1) to receive either Enterprise stent-assisted coiling or Tubridge flow diverter implantation. The primary end point was complete occlusion at 6-month follow-up, while secondary end points included technical success, mortality, target vessel-related stroke, aneurysm bleeding, in-stent stenosis, parent artery occlusion, and the frequency of all adverse events.

RESULTS

Among 185 enrolled subjects, 41 withdrew before procedure initiation. Overall, 82 subjects underwent Tubridge implantation, and 62 subjects were primarily treated with stent-assisted coiling. The results of 6-month follow-up imaging included complete occlusion rates of 75.34% versus 24.53% for the Tubridge and stent-assisted coiling groups, respectively, with a calculated common odds ratio of 9.4 (95% confidence interval, 4.14-21.38; P < .001). There was a higher, nonsignificant frequency of complications for Tubridge subjects. Multivariate analysis showed a decreased stroke rate at the primary investigational site, with a marginal P value (P = .051).

CONCLUSIONS

This trial showed an obviously higher rate of large and giant aneurysm obliteration with the Tubridge FD over Enterprise stent-assisted coiling. However, this higher obliteration rate came at the cost of a nonsignificantly higher rate of complications. Investigational site comparisons suggested that a learning curve for flow-diverter implantation should be recognized and factored into trial designs.

Stent-assisted coiling of intracranial aneurysms using LEO stents: long-term follow-up in 153 patients

PURPOSE

Coiling associated with placement of a self-expandable intracranial stent has improved the treatment of intracranial wide-necked aneurysms. Little is known, however, about the durability of this treatment. The purpose of this report is to present our experience with the LEO stent and to evaluate the complications, effectiveness, and long-term results of this technique.

METHODS

We analyzed the records of 155 intracranial unruptured aneurysms that were treated by stent-assisted coiling with a LEO stent between 2008 and 2012. Procedural, early post-procedural, and delayed complications were recorded. Clinical and angiographic follow-up of patients was conducted over a period of at least 36 months.

RESULTS

No procedural mortality was observed. One-month morbidity was observed in 14 out of 153 patients (9,15%). One hundred thirty-eight patients (with 140 aneurysms) had clinical and angiographic follow-up for more than 36 months. No aneurysm rupture was observed during follow-up. Four patients presented an intra-stent stenosis at 8 months, and 6 patients who had an early recurrence were retreated. Final results showed 85% complete occlusion, 13% neck remnants, and 2% stable incomplete occlusion.

CONCLUSION

Stent-assisted coiling with the LEO stent is a safe and effective treatment for unruptured intracranial aneurysms. The long-term clinical outcomes with the LEO stent are excellent with a high rate of complete occlusion that is stable over time.

Stent-assisted coiling of cerebral aneurysms: a single-center clinical and angiographic analysis

Objective

This study retrospectively compared the clinical and angiographic outcomes of treating cerebral aneurysms with Neuroform (NEU), Enterprise (EP), and Low-profile Visualized Intraluminal Support (LVIS/LVIS Jr) stents.

Materials and methods

We conducted a retrospective analysis of a procedural database. All aneurysm procedures using any of the three types of self-expanding nitinol stents (NEU, EP and LVIS/LVIS Jr) were included. Intra-procedure complications, post-procedure complications, and angiographic results (Raymond–Roy grade scale, RRGS) were analyzed retrospectively. A multivariate logistic regression analysis was conducted to identify predictors of intra-procedure and post-procedure complications.

Results

Two hundred and forty-three aneurysms in 229 patients treated with stent-assisted coiling were included (NEU group: 109 aneurysms; EP group: 61 aneurysms; LVIS/LVIS Jr: 73 aneurysms). The LVIS/LVIS Jr group was associated with the lowest rate of initial complete occlusion (RRGS I: 47.9%; 35/73). Follow-up showed the proportion of RRGS I increased for all stent groups but was greatest in the LVIS/LVIS Jr group. Overall, 17 intra-procedural complications were seen in 229 patients (7.4%) and 15 post-procedural complications were found in 198 patients at follow-up (7.6%), with no differences between stent groups. Thrombotic events were the most common complications and occurred in 13 patients (13/229, 5.7%).

Conclusions

All three types of stents used to treat cerebral aneurysms with unfavorable neck were safe and effective, providing suitable support for the coil mass. LVIS/LVIS Jr promotes better progressive aneurysm complete occlusion than the other two stents but seems to cause more common intra-procedural stent-related thrombotic events and fewer post-procedural complications.

Is there an association between flow diverter fish mouthing and delayed-type hypersensitivity to metals?-a case-control study

PURPOSE

Flow diverters are increasingly used in the treatment of complex and giant intracranial aneurysms. However, they are associated with complications like late aneurysmal rupture. Additionally, flow diverters show focal structural decrease in luminal diameter without any intimal hyperplasia. This resembles a "fish mouth" when viewed en face. In this pilot study, we tested the hypothesis of a possible association between flow diverter fish-mouthing and delayed-type hypersensitivity to its metal constituents.

METHODS

We retrospectively reviewed patient records from our center between May 2010 and November 2015. A total of nine patients had flow diverter fish mouthing. A control group of 25 patients was selected. All study participants underwent prospective patch test to detect hypersensitivity to flow diverter metal constituents. Analysis was performed using logistic regression analysis and Wilcoxon sign rank sum test. Univariate and multivariate analyses were performed to test variables to predict flow diverter fish mouthing.

RESULTS

The association between flow diverter fish mouthing and positive patch test was not statistically significant. In multivariate analysis, history of allergy and maximum aneurysm size category was associated with flow diverter fish mouthing. This was further confirmed on Wilcoxon sign rank sum test.

CONCLUSION

The study showed statistically significant association between flow diverter fish mouthing and history of contact allergy and a small aneurysmal size. Further large-scale studies are needed to detect a statistically significant association between flow diverter fish mouthing and patch test. We recommend early and more frequent follow-up imaging in patients with contact allergy to detect flow diverter fish mouthing and its subsequent evolution.

Clinical and angiographic outcomes following endovascular treatment of very small (3 mm or smaller) intracranial aneurysm: A single-center experience

Treatments for very small (3 mm or smaller) intracranial aneurysms (VSAs) remain controversial. The aim of this study was to evaluate the efficacy of endovascular treatment for VSAs and to evaluate clinical risk factors associated with complications.This retrospective study enrolled 82 VSA patients who underwent coil embolization in our institution. Angiographic outcomes were assessed according to the Meyers classification. The clinical results were evaluated using the modified Rankin scale (mRS) immediately after coiling, at discharge, and during follow-up. A Mann-Whitney U test was performed for non-normally distributed continuous variables. A Pearson χ test or Fisher's exact test was performed for categorical variables.Among 82 aneurysms, 54 were treated with stent-assisted coiling (SAC) embolization. Thromboembolic complications were seen in 2 patients (2.4%). Intraoperative rupture occurred in 4 patients (4.9%). Other adverse events occurred in 2 patients (2.4%). Two patients (2.4%) had permanent disabling neurologic deficit (mRS 3-6) because of complications. The overall mortality rate was 1.2%. Adverse events were correlated with the location of aneurysms (P = .02), Fisher grade (P = .01), and treatment experience (P = .03). Patients with middle cerebral artery (MCA) bifurcation and anterior communicating artery (ACoA) aneurysms were more likely to experience a higher incidence of complication. Thirty-five patients underwent angiographic follow-up. The complete occlusion rate improved from an immediate 37.8% to 80.0% at follow-up.In the short term, coiling is a safe and effective approach for the treatment of VSAs. SAC may be associated with a high rate of further occlusion during short-term follow-up. Endovascular treatment of VSAs at middle cerebral artery bifurcation or anterior communicating artery is associated with a higher incidence of complications.