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

Safety and Efficacy of the Neuroform Atlas Stent for Treatment of Intracranial Aneurysms: A Systematic Review, Meta-Analysis, and Meta-Regression

BACKGROUND

Intracranial aneurysms (IAs) are the major cause of subarachnoid hemorrhage. Stent-assisted coiling, especially with the Neuroform Atlas stent (NAS), has proved more effective than coiling alone for treating these aneurysms.

PURPOSE

To perform a systematic review and meta-analysis to investigate the efficacy and safety of the NAS in treating IAs.

DATA SOURCES

A comprehensive literature search was conducted on PubMed, EMBASE, Cochrane Central Register of Controlled Trials, and clinicaltrials.gov from inception until June 2024.

STUDY SELECTION

We included studies on ruptured and unruptured IAs treated with the NAS, covering experimental, observational, and case series across all age groups. The aneurysm occlusion rate was assessed by using the Raymond-Roy classification (RROC). The mRS and adverse events related to stent use were also recorded.

DATA ANALYSIS

The statistical analysis was conducted on R Version 4.3.2 by using the packages "meta" and "metasens." We reported our results as proportions with their corresponding CIs. Meta-regression, leave-one-out, and sensitivity analyses were conducted to confirm the robustness of our results.

DATA SYNTHESIS

A total of 42 studies including 2434 participants with a mean age of 51 to 73 years were included. Among angiographic outcomes, the final RROC 1/RROC 2 was achieved in 95% of the patients, final RROC 1 in 82%, RROC 2 in 12%, and RROC 3 in 5% of the patients. Additionally, 93% of the patients showed mRS grade 0, 5% showed mRS grade 1, 3% showed mRS grade 2, 2% showed mRS grade 3, 0% showed mRS grade 4, 0% showed mRS grade 5, and 1% showed mRS grade 6. All adverse events had a ≤5% rate.

LIMITATIONS

Due to limited cause-specific data, we were unable to analyze mortality specific to the stent placement and complications. Despite the large number of studies included, comparative studies were still observed to be scarce.

CONCLUSIONS

Although the generalizability of our findings is limited, this study demonstrates that the NAS is highly effective for treating IAs, with high occlusion rates and a low incidence of adverse events. The stent's performance, supported by comprehensive analysis, highlights its safety and efficacy in managing both ruptured and unruptured aneurysms.

Endovascular Embolization of Intracranial Aneurysms Using Target Tetra Detachable Coils: Angiographic and Clinical Results from a Single Center

Background/Objectives: Target tetra detachable coils (TTDCs) aid in achieving effective framing during the coil embolization of small intracranial aneurysms by maintaining a tetrahedral conformation within the aneurysm sac. We aimed to report the initial experience of patients treated for intracranial aneurysms using TTDCs, with a specific focus on efficacy and safety. Methods: We retrospectively reviewed the medical records of 41 patients who underwent the coil embolization of intracranial aneurysms sized ≤10 mm with TTDCs between April and May 2023. Post-procedural angiographic and clinical results were reviewed. Results: Of the 46 aneurysms (45 unruptured and 1 ruptured), 33 (71.7%) were treated with the stent-assisted technique and 13 (28.3%) using the simple coil embolization technique. Post-procedural angiography showed complete occlusion in 41 aneurysms (89.1%), neck remnants in 1 (2.2%), and residual aneurysms in 4 (8.7%). The mean packing density was 34.7% (19.3-46.8%), with TTDC coil length comprising a mean of 88.5% of the total coil length. No major device- or procedure-related complications were observed. During the follow-up, 40 aneurysms (93.0%) demonstrated complete occlusion, while neck remnants were observed in 1 (2.3%), and residual aneurysms in 2 (4.7%). No cases of recanalization were observed. Conclusions: The TTDC is a safe and effective device for the endovascular treatment of intracranial aneurysms. Follow-up studies are required to establish long-term results.

ARISE I Consensus Review on the Management of Intracranial Aneurysms

BACKGROUND

Intracranial aneurysms (IAs) remain a challenging neurological diagnosis associated with significant morbidity and mortality. There is a plethora of microsurgical and endovascular techniques for the treatment of both ruptured and unruptured aneurysms. There is no definitive consensus as to the best treatment option for this cerebrovascular pathology. The Aneurysm, Arteriovenous Malformation, and Chronic Subdural Hematoma Roundtable Discussion With Industry and Stroke Experts discussed best practices and the most promising approaches to improve the management of brain aneurysms.

METHODS

A group of experts from academia, industry, and federal regulators convened to discuss updated clinical trials, scientific research on preclinical system models, management options, screening and monitoring, and promising novel device technologies, aiming to improve the outcomes of patients with IA.

RESULTS

Aneurysm, Arteriovenous Malformation, and Chronic Subdural Hematoma Roundtable Discussion With Industry and Stroke Experts suggested the incorporation of artificial intelligence to capture sequential aneurysm growth, identify predictors of rupture, and predict the risk of rupture to guide treatment options. The consensus strongly recommended nationwide systemic data collection of unruptured IA radiographic images for the analysis and development of machine learning algorithms for rupture risk. The consensus supported centers of excellence for preclinical multicenter trials in areas such as genetics, cellular composition, and radiogenomics. Optical coherence tomography and magnetic resonance imaging contrast-enhanced 3T vessel wall imaging are promising technologies; however, more data are needed to define their role in IA management. Ruptured aneurysms are best managed at large volume centers, which should include comprehensive patient management with expertise in microsurgery, endovascular surgery, neurology, and neurocritical care.

CONCLUSIONS

Clinical and preclinical studies and scientific research on IA should engage high-volume centers and be conducted in multicenter collaborative efforts. The future of IA diagnosis and monitoring could be enhanced by the incorporation of artificial intelligence and national radiographic and biologic registries. A collaborative effort between academic centers, government regulators, and the device industry is paramount for the adequate management of IA and the advancement of the field.

The Enterprise stent…still useful after all these years

BACKGROUND

The Enterprise stent (Codman Neuro, Massachusetts, USA) received Food and Drug Administration (FDA) approval in 2007 for stent-assisted coiling (SAC). Since its introduction, newer stents and devices for aneurysm treatment have been developed resulting in a shift in the utilization of this stent from SAC to other off-label indications.

OBJECTIVE

To describe our experience with the Enterprise stent being used for SAC and other off-label indications.

METHODS

This is a multi-center retrospective review of the use of the Enterprise stent between 2018 and 2023. All patients in which the Enterprise stent was successfully deployed were included in the study.

RESULTS

Our study cohort comprised of 194 patients, mostly females (n = 112, 57.7%), with a mean age of 63.2 years ± 14.3. The Enterprise stent was used for SAC in only 24 (12.4%) patients and was used for rescue stenting in stroke in 101 patients (52.1%), treatment of intracranial stenosis in 53 patients (27.3%), treatment of in-stent stenosis in 1 patient (0.5%), and for treatment of dissections in 15 patients (7.7%). From 2018 to 2023, the use of Enterprise stents for SAC significantly decreased (p < 0.0001) while the use of Enterprise stents for non-SAC purposes was insignificantly variable (p = 0.05).

CONCLUSION

Our study shows that the Enterprise stent remains a reliable tool in neuroendovascular procedures, even if its original intended use has been supplanted by other devices.

Effects of Enterprise 2 stent-assisted coil embolization for wide-necked intracranial aneurysms

BACKGROUND

This study analyzed the safety and efficacy of Enterprise 2 stent-assisted coil embolization for wide-necked intracranial aneurysms by examining stent-vessel apposition, operative complications, embolization outcomes, and clinical outcomes.

METHODS

We retrospectively reviewed the medical records of patients with wide-necked intracranial aneurysms who underwent Enterprise 2 stent-assisted coiling in our hospital from November 2018 to October 2019. Intraoperative VasoCT was performed immediately after stent release in a continuous cohort of patients to observe stent-vessel apposition. Patient demographic, clinical, and imaging data were recorded and analyzed.

RESULTS

A total of 106 wide-necked aneurysms in 106 patients were treated. Stent release was successful in all patients. Twenty-one patients were enrolled consecutively for VasoCT scanning, and incomplete stent apposition was observed in 5 (23.8%). Perioperative complications occurred in 10 patients (9.4%): cerebral infarction in 6, intraoperative coil prolapse in 1, puncture site pseudoaneurysm in 1, deep vein thrombosis at multiple sites in 1, and transient brainstem mass effect in 1. Among the 95 aneurysms with angiographic follow-up, embolization was satisfactory (Raymond-Roy classifications I and II) in 89 (93.7%). Hyperlipidemia was an independent risk factor for incomplete aneurysm occlusion. At the last clinical follow-up, seven patients had a poor clinical outcome (modified Rankin Scale score ≥ 3). Independent risk factors for poor outcomes were preoperative subarachnoid hemorrhage at presentation and cerebral infarction.

CONCLUSION

Enterprise 2 stent-assisted coiling for treatment of wide-necked intracranial aneurysms showed good safety and efficacy; however, incomplete stent apposition can still occur in vessels with a large curvature. Preoperative subarachnoid hemorrhage at presentation and cerebral infarction are the main reasons for poor clinical outcomes after stent-assisted coil embolization.

Low-profile visualized intraluminal support Blue stenting within a Neuroform Atlas stent for a large wide-necked aneurysm: A case report and a bench-top experiment

Low-profile visualized intraluminal support deployment in an Enterprise has been reported; however, that in an Atlas has yet to be in detail. Enterprise has a closed-cell design, while Atlas has an open-cell design. We detail here a case of a large wide-necked aneurysm treated by coil embolization with low-profile visualized intraluminal support Blue deployment within a Neuroform Atlas and a bench-top experiment using a silicon tube to test low-profile visualized intraluminal support, Atlas, Enterprise, and their combinations. A better low-profile visualized intraluminal support expansion was achieved by simultaneously pushing the wire and the system within the Atlas placed at the aneurysm neck, which resulted in an increased metal coverage of the aneurysm neck and a shorter transition zone with low metal coverage at both ends of the aneurysm neck. This technique may enable a high metal coverage by low-profile visualized intraluminal support expansion without restriction by the Atlas and contribute to aneurysm occlusion by increasing the flow-diverting effect.

Treatment of recurrent and residual aneurysms with the low-profile Acandis Acclino stent: Multi-center review of 19 patients

OBJECTIVE

To evaluate the safety and efficacy of the low-profile Acandis Acclino microstent for embolization of recurrent and residual intracranial aneurysms.

METHODS

Consecutive patients treated with the Acclino for aneurysm remnants at three German neurovascular centers were enrolled. The technical success, complications, angiographic and clinical outcome were investigated.

RESULTS

Nineteen patients (median age: 53 years) with 19 aneurysm remnants (median size: 5 mm, anterior circulation: 14) were included. Initial aneurysm treatment consisted of stand-alone coiling in 14 cases, stent-assisted coiling in 4 and clipping in 1. Acclino stent-assisted coil embolization was performed technically successfully in all patients. Morbidity occurred in one patient (5.3%) due to aneurysm perforation. At the angiographic follow-up with a median follow-up duration of 21 months (range: 5-37 months), complete occlusion was obtained in 76.9%. The retreatment rate was 7.7%.

CONCLUSIONS

Retreatment of aneurysm remnants with the Acclino microstent was associated with high aneurysm occlusion rates and acceptable morbidity. Further studies will be necessary to draw a definite conclusion.

Periprocedural Safety and Feasibility of the New LVIS EVO Device for Stent-Assisted Coiling of Intracranial Aneurysms: An Observational Multicenter Study

BACKGROUND AND PURPOSE

Stent-assisted treatment techniques can be an effective treatment option for intracranial aneurysms. The aim of this study was to evaluate the periprocedural feasibility and safety of the new LVIS EVO stent for the treatment of intracranial aneurysms.

MATERIALS AND METHODS

Patients with intracranial aneurysms treated with the LVIS EVO in 11 European neurovascular centers were retrospectively reviewed. Patient and aneurysm characteristics, procedural parameters, immediate grade of occlusion, and technical and clinical complications were assessed.

RESULTS

Fifty-seven patients with 59 aneurysms were treated with the LVIS EVO device; 57.6% of the aneurysms were incidental; 15.3% were acutely ruptured; 15.3% were recanalized or residual aneurysms; and 11.9% were treated for symptoms other than acute hemorrhage. The most frequent aneurysm locations were the middle cerebral artery (25.4%) and the anterior communicating artery (22.0%). The rate of immediate successful deployment was 93.2%. In 6.8% (n = 4) of cases, additional in-stent angioplasty was needed. The immediate complete occlusion rate was 54.2%, while there was a residual aneurysm in 35.6% and a residual neck in 10.2%. Periprocedural technical complications occurred in 7/59 treatments (11.9%; the most frequent technical complication [n = 3] was thrombus formation), which all resolved completely without clinical sequelae. Postprocedural neurologic complications occurred after 4/59 treatments (6.8%; 2 transient ischemic attacks, 1 minor stroke, 1 major stroke), of which only 1 persistent complication was directly related to the procedure (minor stroke in the vascular territory distal to the stent).

CONCLUSIONS

The LVIS EVO stent is a safe, feasible device for the treatment of intracranial aneurysms.

Evaluation of the Accero Stent for Stent-Assisted Coiling of Unruptured Wide-Necked Intracranial Aneurysm Treatment with Short-Term Follow-Up

BACKGROUND

Stent-assisted coiling is an effective method of treating intracranial aneurysms. The aim of the study was to assess the safety and efficacy of the new Accero stent for the treatment of intracranial aneurysms.

MATERIALS AND METHODS

It was a retrospective, single-center study. Eighteen unruptured intracranial aneurysms were treated using the stent-assisted coiling method with the Accero stent. Patient demographics, aneurysm characteristics, procedural parameters, grade of occlusion, complications, and clinical results were analyzed. Follow-up magnetic resonance (MR) was performed 6 months after intervention.

RESULTS

Seventeen patients with 18 incidental unruptured aneurysms were electively treated with coiling and the Accero stent. The aneurysms were located on internal carotid artery (ICA), middle cerebral artery (MCA) and basilar artery (BA). All stents were deployed successfully. Immediate complete occlusion rate Raymond-Roy occlusion classification (RROC) class I was achieved in 13 cases and class II in 4 cases. Complications occurred in 2/17 treatments and included guidewire stent perforation with subarachnoid hemorrhage (SAH) and stent deformation. Vascular spasm in the subarachnoid hemorrhage (SAH) patient subsided before discharge. Ninety days after intervention, the modified Rankin Scale (mRS) value was 0. RROC class I was observed in 88.23% of cases in follow-up.

CONCLUSION

The Accero stent provides excellent support for coil mass. It constitutes an efficacious device with good initial occlusion rate for treating wide-necked unruptured intracranial aneurysms.