Stent-assisted coil embolization of unruptured middle cerebral artery aneurysms using LVIS Jr. stents

Use of the Neuroform Atlas Stent or LVIS Jr Stent for Treatment of Unruptured Intracranial Aneurysms in Parent Arteries of <2 mm in Diameter: A Multicenter Experience

BACKGROUND AND PURPOSE

The Neuroform Atlas stent and the LVIS Jr stent are intracranial microstent systems for the treatment of wide-neck intracranial aneurysms. Hence, this study aimed to compare the efficacy and safety of the Neuroform Atlas stent and the LVIS Jr stent for the treatment of unruptured intracranial aneurysms in parent arteries of <2 mm in diameter.

MATERIALS AND METHODS

From March 2022 to April 2023, the clinical and imaging data of 135 patients with unruptured intracranial aneurysms treated with stent-assisted coiling using the Neuroform Atlas or LVIS Jr stent in parent arteries of <2 mm in diameter were retrospectively analyzed. Stent apposition was evaluated by high-resolution conebeam CT (HR-CBCT). Immediate aneurysm-embolization attenuation and occlusion at 6-month follow-up were evaluated using 2D DSA and the modified Raymond-Roy classification. Adverse events were recorded. Multivariate logistic regression analysis was undertaken to determine the independent factors affecting incomplete stent apposition.

RESULTS

One hundred thirty-five patients (135 aneurysms) underwent stent-assisted coiling (66 Neuroform Atlas stents and 69 LVIS Jr stents). Intraoperative HR-CBCT showed that 1 Neuroform Atlas stent and 11 LVIS Jr stents had incomplete stent apposition at the aneurysm neck (P <  .05). Perioperative complications occurred in 3 cases (2.22%). These comprised 2 cases of neurologic complications (1 case of distal intracranial vascular embolism and 1 case of cerebral parenchymal hemorrhage) and 1 case of severe postprocedural gastrointestinal hemorrhage. DSA follow-up showed 3 cases of aneurysm recurrence in the LVIS Jr group. Multivariate regression analysis showed that a stent angle of ≥75° (OR, 23.963; P = .005) or a parent artery diameter mismatch ratio of ≥1.25 (OR, 8.043; P = .037) were risk factors for incomplete stent apposition, especially for the LVIS Jr stent (OR, 20.297; P = .015).

CONCLUSIONS

The Neuroform Atlas stent and LVIS Jr stent are efficacious in the treatment of unruptured intracranial aneurysms in parent arteries of <2 mm in diameter. Apposition of the LVIS Jr stent was worse than in the Neuroform Atlas stent at the neck of some aneurysms.

Safety and efficacy of the novel Alpha stent for the treatment of intracranial wide-necked aneurysm

The Alpha stent is an intracranial closed-cell stent with a unique mesh design to enhance wall apposition. It recently underwent structural modifications to facilitate easier stent deployment. This study aimed to evaluate the safety and efficacy of stent-assisted coil embolization for unruptured intracranial aneurysms using the Alpha stent. Between January 2021 and November 2021, 35 adult patients with 35 unruptured intracranial aneurysms in the distal internal carotid artery were prospectively enrolled. For efficacy outcomes, magnetic resonance angiography at the 6-month follow-up was evaluated using the Raymond-Roy occlusion classification (RROC). The safety outcome evaluated the occurrence of symptomatic procedure-related neurological complications up to 6 months postoperatively. Technical success was achieved in 34/35 (97.1%). Six months postoperatively, aneurysm occlusion showed RROC I in 32/35 (91.4%) and RROC II in 3/35 (8.6%) patients. Procedure-related neurologic complications occurred in one patient (2.9%) who experienced hemiparesis due to acute lacunar infarction, which resulted in a 6-month mRS score of 1. The Alpha stent demonstrated excellent efficacy and safety outcomes in stent-assisted coil embolization of unruptured distal ICA aneurysms. The recent structural modifications allowed for easier stent delivery and deployment.Clinical trial registration number: KCT0005841; registration date: 28/01/2021.

Statistical Analysis of the Factors that Affect Postoperative Length of Hospital Stay after Unruptured Intracranial Aneurysm Treatment in Japan: A 20-year Nationwide Multicenter Study

Treatment strategies for unruptured intracranial aneurysms (UIAs) should be carefully considered with reference to rupture and complication rates. It is also important to minimize the length of hospital stay (LOS) and to ensure a high quality of medical care. In this study, we aim to clarify the factors that affect the LOS of patients treated for UIAs using the Inpatient Clinico-Occupational Database of the Rosai Hospital Group (ICOD-R). This was a nationwide-multicenter study based on ICOD-R data from 2000 to 2019. Patients diagnosed with UIAs who were treated with clipping or coiling were included in the study. Multivariate analysis was performed to identify the factors affecting LOS. LOS was also compared between groups classified by surgical procedure or treatment period. We identified 3294 patients on the database who underwent clipping or coiling of UIAs during the study period. Multivariate analysis revealed hospital admission during the early 2000s and the late 2010s, age, and treating institution to be significantly correlated with LOS (p < 0.05). There was a significant difference between the mean LOS of the clipping group (20.3 days) and the coiling group (9.65 days) (p < 0.001). Compared by treatment period, LOS significantly shortened over time. Our results suggest that the type of treatment, time of treatment, patient age, and the treating institution affect postoperative LOS for UIAs. Although coiling was found to lead to a lower average LOS than clipping, treatment selection should take the characteristics of each patient's aneurysm into consideration.

Systematic Review and Meta-Analysis of Endovascular Therapy Effectiveness for Unruptured Saccular Intracranial Aneurysms

Background

Currently, endovascular treatment of intracranial aneurysms (ICAs) is limited by low complete occlusion rates. The advent of novel endovascular technology has expanded the applicability of endovascular therapy; however, the superiority of novel embolic devices over the traditional Guglielmi detachable coils (GDCs) is still debated. We performed a systematic review of literature that reported Raymond-Roy occlusion classification (RROC) rates of modern endovascular devices to determine their immediate and follow-up occlusion effectiveness for the treatment of unruptured saccular ICAs.

Methods

A search was conducted using electronic databases (PUBMED, Cochrane, ClinicalTrials.gov, Web of Science). We retrieved studies published between 2000-2022 reporting immediate and follow-up RROC rates of subjects treated with different endovascular ICA therapies. We extracted demographic information of the treated patients and their reported angiographic RROC rates.

Results

A total of 80 studies from 15 countries were included for data extraction. RROC rates determined from angiogram were obtained for 21,331 patients (72.5% females, pooled mean age: 58.2 (95% CI: 56.8-59.6), harboring 22,791 aneurysms. The most frequent aneurysm locations were the internal carotid artery (46.4%, 95% CI: 41.9%-50.9%), the anterior communicating artery (26.4%, 95% CI: 22.5%-30.8%), the middle cerebral artery (24.5%, 95% CI:19.2%-30.8%) and the basilar tip (14.4%, 95% CI:11.3%-18.3%). The complete occlusion probability (RROC-I) was analyzed for GDCs, the Woven EndoBridge (WEB), and flow diverters. The RROC-I rate was the highest in balloon-assisted coiling (73.9%, 95% CI: 65.0%-81.2%) and the lowest in the WEB (27.8%, 95% CI:13.2%-49.2%). The follow-up RROC-I probability was homogenous in all analyzed devices.

Conclusions

We observed that the coil-based endovascular therapy provides acceptable rates of complete occlusion, and these rates are improved in balloon-assisted coils. Out of the analyzed devices, the WEB exhibited the shortest time to achieve >90% probability of follow-up complete occlusion (~18 months). Overall, the GDCs remain the gold standard for endovascular treatment of unruptured saccular aneurysms.

Safety and Efficacy of Endovascular Coils and Non-Flow-Diverting Stents for Management of Unruptured Intracranial Aneurysms: A Location-Specific Outcomes Analysis

INTRODUCTION

The relationship between the anatomical location of an unruptured saccular aneurysm, the efficacy, and the potential complications associated with coil and non-flow-diverting stents remains poorly documented. Therefore, the aim of this study is to evaluate the efficacy and safety of endovascular treatment based on the anatomical position of the unruptured intracranial aneurysm (UIA).

METHODS

A retrospective cohort study was conducted using an anonymized database of patients who underwent endovascular therapy for UIAs between 2014 and 2021.

RESULTS

A total of 138 patients with 147 UIAs were included. Immediate Raymond-Roy occlusion class I or II was achieved in 99.2% of patients in all anatomical locations, with a 96.2% occlusion rate at the 12-month follow-up. Complications occurred more frequently in the anterior cerebral artery (35%) and internal carotid artery in its ophthalmic segment (25%). However, the difference was not statistically significant.

CONCLUSIONS

Our study shows that endovascular treatment with stents and coils is effective and safe for managing UIAs in various anatomical locations. The incidence of thromboembolic complications was significantly higher for UIAs located in the anterior cerebral artery.

Trends in the Age of Patients Treated for Unruptured Intracranial Aneurysms from 1990 to 2020

BACKGROUND

The decision for treatment for unruptured intracranial aneurysms (UIAs) is often difficult. Innovation in endovascular devices have improved the benefit-to-risk profile especially for elderly patients; however, the treatment guidelines from the past decade often recommend conservative management. It is unknown how these changes have affected the overall age of the patients selected for treatment. Herein, we aimed to study potential changes in the average age of the patients that are being treated over time.

METHODS

A systematic search of the literature was performed to identify all studies describing the age of the UIAs that were treated by any modality. Scatter diagrams with trend lines were used to plot the age of the patients treated over time and assess the presence of a potential significant trend via statistical correlation tests.

RESULTS

A total of 280 studies including 83,437 UIAs treated between 1987 and 2021 met all eligibility criteria and were entered in the analysis. Mean age of the patients was 55.5 years, and 70.7% were female. There was a significant increasing trend in the age of the treated patients over time (Spearman r: 0.250; P < 0.001), with a 1-year increase in the average age of the treated patients every 5 years since 1987.

CONCLUSIONS

The present study indicates that based on the treated UIA patient data published in the literature, older UIAs are being treated over time. This trend is likely driven by safer treatments while suggesting that re-evaluation of certain UIA treatment decision scores may be of great interest.

Embolization of unruptured wide-necked aneurysms at the MCA bifurcation using the Neuroform atlas stent-assisted coiling: a two-center retrospective study

Background

The management of middle cerebral artery (MCA) aneurysms remains a controversial topic, and MCA aneurysms have traditionally been treated primarily by surgical clipping. The Neuroform Atlas Stent™ (NAS, available from Stryker Neurovascular, Fremont, California) represents the latest generation of intracranial stents with improved stent delivery system capabilities.

Objective

This study aims to investigate the safety, feasibility and efficacy exhibited by NAS in treating unruptured aneurysms at the MCA bifurcation.

Methods

This was a two-center retrospective study involving 42 patients with unruptured wide-necked aneurysms (WNAs) of the MCA treated with the NAS from October 2020 to July 2022.

Results

The stent was used to treat 42 cases of unruptured WNA at the MCA bifurcation. Endovascular treatment techniques had a 100% success rate. Immediate postoperative angiography found complete aneurysm occlusion in 34 patients (80.9%) (mRRC 1), neck remnant in 7 patients (16.7%) (mRRC 2), and residual aneurysm in 1 patient (2.4%) (mRRC 3). The thromboembolic complication rate was 2.4% (1/42). The follow-up period was 8.7 months on average (3-16 months). The last angiographic follow-up results revealed complete aneurysm occlusion in 39 patients (92.9%) (mRRC 1), neck remnant in 3 (7.1%) patients (mRRC 2), no aneurysm recanalization or recurrence, and no cases of stent intimal hyperplasia. During the latest clinical follow-up, all patients had an mRS score of 0.

Conclusion

Our study demonstrates that the NAS can be applied to treat unruptured WNAs at the MCA bifurcation with favorable safety, feasibility, and efficacy.

Need for Y-stenting in stent-assisted coiling of wide-neck bifurcation aneurysms

BACKGROUND AND PURPOSE

Stent-assisted coiling of wide neck bifurcation aneurysms in the anterior communicating segment and basilar tip region can be performed with varying stent configurations, including single stenting or Y-stenting. Y-stenting requires two stents and thus incurs greater cost and procedural complexity than single-stent constructs. The influence of first stent type on the need for Y-stenting remains unknown.

MATERIALS AND METHODS

Clinical and angiographic data were retrospectively obtained for patients that underwent stent-assisted coiling for basilar tip or anterior communicating aneurysms at a high-volume center. Patients were included in this study if stent-assisted coiling was performed using Neuroform Atlas or LVIS Jr stents. A multivariate binary logistic regression was performed to measure the influence of first stent type on the need for Y-stenting.

RESULTS

Stent-assisted coiling was used to treat 82 aneurysms in 81 patients during the study period, and Y-stenting was performed in 18.3% (15/82) of cases. In multivariate logistic regression analysis, use of LVIS Jr. as the first stent did not significantly influence the need for subsequent Y-stenting after controlling for aneurysm morphology (OR 0.65, 95% CI 0.18-2.43).

CONCLUSION

Controlling for aneurysm morphology and location, the use of Y-stenting for stent-assisted coiling was not independently influenced by the choice of LVIS Jr or Neuroform Atlas as the first stent. A larger cohort may reveal differences between these two stents, particularly for aneurysms with large neck sizes.

Long-term outcomes of Y-stent-assisted coil embolization using Low-profile Visualized Intraluminal Support Junior (LVIS Jr) for intracranial bifurcation aneurysms

OBJECTIVE

Y-stent-assisted coil embolization is indicated for the treatment of complex intracranial bifurcation aneurysms. However, the long-term outcomes associated with this technique remain unclear. The purpose of this study was to evaluate the long-term outcomes of Y-stent-assisted coil embolization using the Low-profile Visualized Intraluminal Support Junior (LVIS Jr) device.

METHODS

We retrospectively reviewed our databases to identify patients treated with Y-stent-assisted coiling using LVIS Jr. Digital subtraction angiography, silent magnetic resonance angiography (MRA), and time-of-flight MRA were performed at 1 year after the procedure. Patients also received an annual follow-up using MRA. Aneurysm occlusion status was classified into complete occlusion (CO), neck remnant (NR), and body filling (BF). Clinical outcomes were assessed using the modified Rankin Scale.

RESULTS

Twenty-one patients (22 aneurysms) were included in this study. All procedures were performed successfully. Immediate postprocedural angiograms showed CO in 13 aneurysms (59.1%), NR in two aneurysms (9.1%), and BF in seven aneurysms (31.8%). One-year follow-up angiograms revealed CO in 86.4% of patients. Only one patient had a major recurrence and required retreatment. The mean follow-up duration was 43.5 months. The last angiographic studies demonstrated CO in 18 aneurysms (81.8%), NR in three aneurysms (13.6%), and BF in one aneurysm (4.5%). Periprocedural and delayed complications occurred in two patients and one patient, respectively. There was no permanent morbidity or death. The modified Rankin Scale scores at last clinical follow-up were equal to those before the procedures in all patients.

CONCLUSION

Y-stent-assisted coil embolization using LVIS Jr for intracranial bifurcation aneurysms has favorable long-term angiographic and clinical outcomes.

Coil Embolization of Unruptured Cerebral Aneurysms Using Stents in Small Arteries Less Than 2 mm in Diameter

BACKGROUND

Data regarding the safety and effectiveness of stent placement in small vessels (<2 mm in diameter) for treating wide-necked cerebral aneurysms are limited.

OBJECTIVE

To report our experience regarding coil embolization of unruptured cerebral aneurysms using stents (specifically the Neuroform Atlas) in small arteries <2 mm in diameter.

METHODS

Patients with unruptured cerebral aneurysms treated with stent-assisted coil embolization between March 2017 and March 2021 in our hospital were included.

RESULTS

Of the 137 cerebral aneurysms included in this study, 49 required stent placement and 48 were treated using the Neuroform Atlas in the small vessels measuring <2 mm in diameter (small vessel group [SVG]). In the SVG, 43 aneurysms (87.8%) demonstrated complete occlusion. Regarding complications, 2 (4.1%) patients had in-stent thrombosis during procedures and 5 (10.2%) experienced symptomatic thromboembolic complications, but only 2 (4.1%) had worsening of the modified Rankin scale ≥1 at 90 days after embolization. Patients with middle cerebral artery aneurysms had a higher risk of thrombotic events (5/18 patients, 27.8%), such as symptomatic thromboembolic complications or intraprocedural in-stent thrombus than those with other aneurysms (1/31 patients, 3.2%), in the SVG (P = .0167).

CONCLUSION

Stent-assisted coil embolization for unruptured cerebral aneurysms using stents, especially the Neuroform Atlas, in small arteries <2 mm in diameter is effective and feasible, but careful perioperative attention should be given to thrombotic events during the embolization of middle cerebral artery aneurysms.

Clinical and Angiographic Outcomes After Stent-Assisted Coiling of Cerebral Aneurysms With Laser-Cut and Braided Stents: A Comparative Analysis of the Literatures

Introduction: Stent-assisted coiling (SAC) plays an important role in endovascular treatment of intracranial aneurysms (IAs). This comparative analysis examines the safety and efficacy of SAC in general and compares clinical and angiographic outcomes between laser-cut stents and braided stents.

Methods: Relevant English-language studies were identified via a PubMed search for published articles regarding outcomes of SAC using laser-cut stents and braided stents published from 2015 to 2020. Data from 56 studies that met our inclusion criteria were pooled and statistically compared.

Results: A total of 4,373 patients harboring with 4,540 IAs were included. Patients were divided into two groups on the basis of stent type: laser-cut stents (2,076 aneurysms in 1991 patients; mean follow-up, 12.99 months) and braided stents (2,464 aneurysms in 2382 patients; mean follow-up, 18.41 months). Overall, the rates of successful stent deployment, thromboembolic events, stent stenosis, periprocedural intracranial hemorrhage, permanent morbidity, mortality, and recanalization were 97.72, 4.72, 2.87, 1.51, 2.14, 1.16, and 6.06%, respectively. Laser-cut stents were associated with a significantly higher rate of successful deployment (p = 0.003) and significantly lower rate of periprocedural intracranial hemorrhage (p = 0.048). Braided stents were associated with a significantly lower rate of permanent morbidity (p = 0.015).

Conclusion: SAC of IAs using laser-cut stents or braided stents was effective and safe. Rates of thromboembolic events, stent stenosis, mortality, and recanalization were comparable between the stent types. Braided stents were associated with lower permanent morbidity while laser-cut stents were associated with more favorable rates of successful deployment and periprocedural intracranial hemorrhage.