Pivotal Trial of the Neuroform Atlas Stent for Treatment of Anterior Circulation Aneurysms: One-Year Outcomes

Single Neuroform Atlas stent: a reliable approach for treating complex wide-neck bifurcated aneurysms

Background

Treating wide-neck bifurcated cerebral aneurysms (WNBAs) using various techniques and new devices has shown favorable outcomes. However, endovascular coiling can be technically challenging when the aneurysm neck is incorporated into the parent vessel. Furthermore, although recent research has reported favorable outcomes of Neuroform Atlas stent (NAS)-assisted coiling, broad inclusion criteria have hampered precise evaluations of their effectiveness and safety for treating complex WNBAs. Therefore, this study evaluated whether the use of a single NAS is a safe and effective approach for treating complex WNBAs.

Methods

We treated 76 complex WNBAs (unruptured, n = 49; ruptured, n = 27) using single NAS-assisted coil embolization and retrospectively analyzed the clinical and angiographic outcomes.

Results

In a cohort of 68 patients (mean age, 58.3 ± 11.6 years; males n = 20, 29.4%; females, n = 48, 70.6%), 76 stents were successfully delivered to the target aneurysms, yielding a technical success rate of 98.6%. Complete occlusion was evident in 59 (77.6%) of 76 aneurysms, with neck remnants found in 16 (21.1%) and partial occlusion in 1 (1.3%). Treatment-related morbidities comprised one branch occlusion and one parenchymal hemorrhage. However, no new neurological symptoms of unruptured aneurysms were evident at discharge. The outcomes of 20 of the 27 ruptured aneurysms were favorable (Glasgow Outcome Scale scores of 4 or 5) at the final follow-up assessment (mean 12.2 [6-29] months), except for one initial subarachnoid hemorrhage. Post-treatment angiography revealed complete occlusion in 89.1%, neck remnants in 7.8%, and incomplete occlusion in 3.1% of the aneurysms. Approximately 88.2% of the patients were assessed at least once by follow-up diagnostic or magnetic resonance angiography (mean, 12.5 ± 4.3 [range, 6-29] months), with five (7.8%) minor and two (3.1%) major recurrences.

Conclusion

A single NAS is safe and effective for treating WNBAs incorporated into parent vessels.

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.

Neuroform atlas stent treatment for 533 intracranial aneurysms in a large Chinese cohort: complication risk factor analysis

BACKGROUND

The newest generation of Neuroform Atlas stent™ (Stryker, Fremont, California) represents a recent advance of cerebral laser-cut microstents for the treatment of intracranial wide-necked aneurysms, and postoperative complications have been observed among Western patients. We assessed predictors of complications, morbidity, and unfavourable outcomes in a large cohort of patients with aneurysms that were treated with Neuroform Atlas stents in China.

METHODS

This retrospective study included subjects who were treated with Atlas stents in China from November 2020 to January 2022.

RESULTS

A total of 522 consecutive patients (mean age, 58.9 ± 9.9 years; female, 65.3% [341/522]) with 533 aneurysms were included in the study. In the early postoperative period, the neurological morbidity rate was 7.3% (38/522), the ischaemic stroke rate was 5.0% (26/522), the aneurysm rupture subarachnoid haemorrhage rate was 2.3% (12/522), and the mRS score deterioration rate was 5.4% (28/522). The mortality rate was 0.8% (4/522) in the postoperative period. The rate of neurological morbidity during the follow-up period was 1.2% (6/486). In the multifactor prediction analysis, cerebral infarction, Hunt-Hess grade (3-5), procedure duration, stent length and coil protrusion into the parent artery were found to be independent predictors of neurologic morbidity. The procedure duration, stent length and coil protrusion into the parent artery were found to be independent predictors of mRS score deterioration.

CONCLUSIONS

The incidence of SCA (stent-assisted coiling)-related complications with the Atlas stent in this study population was comparable to that in Western populations. We identified the procedure duration and stent length as novel independent predictors of SCA-related ischaemic stroke, neurological morbidity, and mRS score deterioration among the Chinese population.

Large Single-Center Experience with Short-Term Follow-up of Neqstent-Assisted Coiling

BACKGROUND AND PURPOSE

Endovascular treatment of wide-neck bifurcation aneurysms has historically proved difficult with variable outcomes. Different endovascular techniques such as balloon-assisted coiling, stent-assisted coiling, or intrasaccular devices provide a varied range of efficacy and safety. Neqstent-assisted coiling is a new device and technique that aim to provide a maximum of both. We analyzed the early clinical and radiologic outcomes after the use of this new technique and device in our practice.

MATERIALS AND METHODS

This study was a retrospective analysis of ruptured and unruptured intracranial aneurysms treated with the Neqstent. The primary radiologic outcomes were quantified on DSA, CTA, or MRA using the modified Raymond-Roy criteria. The outcomes were defined as immediate complete occlusion (modified Raymond-Roy criteria 1) and complete (modified Raymond-Roy criteria 1) and adequate occlusion (modified Raymond-Roy criteria 1 and modified Raymond-Roy criteria 2) at 6 months posttreatment. The primary safety outcome was the rate of device-related adverse events. Secondary safety outcomes included time to discharge and change in the mRS score at 6-month follow-up.

RESULTS

Twenty patients were treated with the Neqstent from November 2020 to January 2023. Nine had unruptured aneurysms, and 11 were patients with subarachnoid haemorrhage due to ruptured aneurysms. Eighteen of 20 aneurysms (90%) treated demonstrated complete occlusion (modified Raymond-Roy criteria 1) on immediate postembolization angiograms. Sixteen of 17 aneurysms treated (94.1%) remained adequately occluded on 6-month follow-up (modified Raymond-Roy criteria 1 and modified Raymond-Roy criteria 2). Immediate postoperative complications occurred in 2 patients; only 1 patient had residual neurologic deficits at 6 months (mRS = 2).

CONCLUSIONS

Management of large, wide-neck aneurysms remains difficult, with high rates of recurrence and complications. The use of the Neqstent shows promising short-term results for the treatment of complex wide-neck aneurysms. Initial complication rates for our cohort were relatively high. However, this result is likely related to the initial learning experience of device deployment and the use of antiplatelets.

High-resolution vessel wall imaging for quantitatively and qualitatively evaluating in-stent stenosis of intracranial aneurysms

Background

It is critical to accurately and noninvasively evaluate the stented parent artery of intracranial aneurysms (IAs) with endovascular treatment.

Objective

To investigate high-resolution vessel wall imaging (HR-VWI) for quantitative and qualitative evaluation of in-stent stenosis (ISS) in IAs treated with stent placement (SP).

Methods

Fifty-five patients (58 aneurysms) underwent HR-VWI, contrast-enhanced (CE)-HR-VWI, CE-MR angiography (MRA), time-of-flight (TOF)-MRA, and digital subtraction angiography (DSA) six months after SP, and the reliability of quantitative stent lumen measurements was evaluated by intraclass correlation coefficient (ICC) analysis. Agreement and correlation of quantitative evaluation were estimated by comparing the four MR imaging modalities with DSA. The diagnostic performance for >0%, ≥25%, and ≥50% of ISS degrees and overall diagnostic accuracy for the ISS degrees of the four MR imaging modalities were calculated to qualitative evaluation.

Results

The reliability of CE-HR-VWI and HR-VWI for ISS quantitative measurements was excellent (ICC 0.955-0.989). The agreement and correlation of CE-HR-VWI, HR-VWI versus DSA for ISS quantitative measurements were better than those of CE-MRA and TOF-MRA (p < 0.05). The diagnostic performance for distinguishing the degree of ISS >0%, ≥25%, and ≥50% by CE-HR-VWI and HR-VWI was superior to CE-MRA and TOF-MRA, and their overall diagnostic accuracy was 96.55 and 94.83%, respectively. HR-VWI and CE-HR-VWI were not statistically significant in the quantitative and qualitative evaluation of ISS performance (p > 0.05).

Conclusion

HR-VWI and CE-HR-VWI have similar performance and value in the quantitative and qualitative evaluation of ISS, and HR-VWI without contrast media could be used as an ideal long-term follow-up approach after SP treatment for IAs.

Safety and effectiveness of the LVIS and LVIS Jr devices for the treatment of intracranial aneurysms: Final results of the LEPI multicenter cohort study

BACKGROUND

The Low profile visualized intraluminal support (LVIS)/LVIS Jr is a self-expanding braiding stent for the treatment of intracranial aneurysm. This study is to determine the safety and effectiveness of the LVIS/LVIS Jr for the treatment of intracranial aneurysms in a real-world setting.

METHODS

This prospective, observational, multicenter study enrolled patients with unruptured, ruptured and recanalized intracranial aneurysms treated with the LVIS stents, between February 2018 to December 2019. Primary endpoint was the cumulative morbidity and mortality rate (CMMR) assessed at 12 months follow-up (FU).

RESULTS

A total of 130 patients were included (62.3 % women, mean age 55.9 ± 11.4) on an intention-to-treat basis. Four patients (3.1 %) had 2 target aneurysms; 134 total aneurysms were treated. The aneurysms were mainly located on the middle cerebral artery (41/134; 30.6 %) and the anterior communicating artery (31/134; 23.1 %). The CMMR at 1 year linked to the procedure and/or device was 4.6 % (6/130). The overall mortality was 1.5 % (2/130), none of these deaths adjudged as being linked to the procedure and/or device. All aneurysms (134/134, 100 %) were successfully treated with LVIS stent and/or other devices. At a mean FU of 16.8 months post-procedure, complete/nearly complete occlusion was achieved in 112 aneurysms (92.6 %), and only 3 patients (2.5 %) required aneurysm retreatment.

CONCLUSION

This study provides evidence that the LVIS/LVIS Jr devices are safe and effective in the treatment of complex intracranial aneurysms, with very high rates of adequate occlusion at FU. These angiographic results are stable over time with an acceptable complication rate.

TRIAL REGISTRATION

ClinicalTrial.gov under NCT03553771.

Pipeline embolization device versus Atlas stent assisted coiling for intracranial aneurysm treatment: a retrospective, propensity score matched study with a focus on midterm outcomes and hospital costs

BACKGROUND

Stent assisted coiling (SAC) and flow diverters (FDs) are common endovascular treatments for wide necked cerebral aneurysms, but studies comparing the new generation Atlas SAC and FDs are scarce. We performed a propensity score matched (PSM) cohort study to compare the Atlas SAC and the pipeline embolization device (PED) for proximal internal carotid artery (ICA) aneurysms.

METHODS

Consecutive ICA aneurysms treated at our institution with either the Atlas SAC or PED were studied. PSM was used to control for age, sex, smoking, hypertension, and hyperlipidemia, and the rupture status, maximal diameter, and neck size of the aneurysm (aneurysms >15 mm and non-saccular aneurysms were excluded). Midterm outcomes and hospital costs were compared between these two devices.

RESULTS

A total of 309 patients with 316 ICA aneurysms were included. Following PSM, 178 aneurysms treated with the Atlas SAC and PED were matched (n=89 in each group). Aneurysms treated with the Atlas SAC required a slightly longer procedure time, but had lower hospital costs than those treated with the PED (115.2±24.6 vs 102.4±40.8 min, P=0.012; $27 650.2±$6961.4 vs $34 107.0±$3707.2, P<0.001). Atlas SAC and PED treatments showed equivalent aneurysm occlusion rates (89.9% vs 86.5%, P=0.486), complication rates (5.6% vs 11.2%, P=0.177), and a favorable functional outcome (96.6% vs 97.8%, P=1.0) at follow-up (8.2±3.0 vs 8.4±4.2 months, P=0.652).

CONCLUSION

In this PSM study, midterm outcomes of the PED and Atlas SAC in the treatment of ICA aneurysms were similar. However, SAC required a longer operation time, and the PED may increase the economic cost of inpatients in Beijing, China.

A Novel Braided Stent With Customized Simulation Software for Treatment of Intracranial Aneurysms: Multicenter Prospective Trial Before Unrestricted Clinical Application

BACKGROUND AND OBJECTIVES

Planning/guidance software became important tools for physicians' presurgical optimal decision-making. However, there are no intracranial stent products with specifically associated simulation software. We report the "premarket" clinical trial of a new braided stent with a customized simulation software.

METHODS

A stent system with 3 mesh density types (16, 24, and 32 wire mesh) was designed based on computational flow dynamics technology, and a simulation software (virtual stent planner [VSP]) was developed for the optimal stent deployment planning. Stents were selected after simulation on preoperative 3D-processed angioimages, and accuracy of the VSP was evaluated.

RESULTS

Thirty-three unruptured intracranial aneurysms were successfully treated with VSP guidance. Twenty aneurysms (61%) were anterior circulation aneurysms, and 13 (39%) were posterior circulation aneurysms. The average aneurysm size was 7.1 mm, and the mean follow-up period was 19.2 months (11-39.0). There was no major recurrence or retreatment during follow-up, 2 morbidity cases, and no mortality. VSP planning presented slightly smaller stent dimensions compared with postdeployment: 24.2 vs 25.5 mm average, error -1.3 mm, and difference rate-5.46%.

CONCLUSION

Based on this result, the new stents and software guidance system were approved by the Ministry of Health and Welfare as a combined medical device. VSP provided precise deployment with minimal error compared with actual stent and can contribute to better stent deployment even for less experienced physicians.

Short- versus long-term Dual AntiPlatelet Therapy for Stent-Assisted treatment of CErebral aneurysm (DAPTS ACE): a multicenter, open-label, randomized clinical trial

BACKGROUND

The optimal duration of dual antiplatelet therapy (DAPT) after stent-assisted coil embolization (SACE) for cerebral aneurysm remains uncertain. This randomized trial of short- versus long-term Dual AntiPlatelet Therapy for Stent-Assisted treatment of CErebral aneurysm (DAPTS ACE) aimed to clarify whether long-term DAPT can reduce the occurrence of ischemic stroke in patients with cerebral aneurysms treated by SACE compared with short-term DAPT.

METHODS

Patients treated for cerebral aneurysm with SACE were enrolled from 17 hospitals in Japan. Patients were enrolled within 30 days after SACE and assigned in a 1:1 ratio to receive long-term (12 months) or short-term (3 months) DAPT with aspirin and clopidogrel. Randomization was performed centrally through a web-based system. The primary outcome was the time to ischemic stroke event during 3 to 12 months after SACE. This trial was registered with the Japan Registry of Clinical Trials (jRCTs051180141).

RESULTS

A total of 142 patients were recruited from November 4, 2016 to January 7, 2019. Among them, 65 and 68 patients assigned to the long- and short-term DAPT groups, respectively, were included in the full analysis set. Ischemic stroke occurred in no patients in the long-term DAPT group and in one patient in the short-term DAPT group. The incidence rate did not differ between the groups (0.0 vs 2.1/100 person-years; log rank test, P=0.33).

CONCLUSIONS

In this multicenter randomized controlled trial, there was not a statistically significant difference in the rate of ischemic strokes between long- and short-term DAPT.

Silent Embolic Infarction after Neuroform Atlas Stent-Assisted Coiling of Unruptured Intracranial Aneurysms

OBJECTIVE

There is still controversy regarding whether neck remodeling stent affects the occurrence of silent embolic infarction (SEI) after aneurysm coiling. Thus, the aim of the present study is to investigate the incidence of SEI after stent-assisted coiling (SAC) using Neuroform Atlas Stent (NAS) and possible risk factors. This study also includes a comparison with simple coiling group during the same period to estimate the impact of NAS on the occurrence of SEI.

METHODS

This study included a total of 96 unruptured intracranial aneurysms in 96 patients treated with SAC using NAS. Correlations of demographic data, aneurysm characteristics, and angiographic parameters with properties of SEI were analyzed. The incidence and characteristics of SEI were investigated in 28 patients who underwent simple coiling during the same period, and the results were compared with the SAC group.

RESULTS

In the diffusion-weighted imaging obtained on the 1st day after SAC, a total of 106 SEI lesions were observed in 48 (50%) of 96 patients. Of these 48 patients, 38 (79.2%) had 1-3 lesions. Of 106 lesions, 74 (69.8%) had a diameter less than 3 mm. SEI occurred more frequently in older patients (≥60 years, p=0.013). The volume of SEI was found to be significantly increased in older age (≥60 years, p=0.032), hypertension (p=0.036), and aneurysm size ≥5 mm (p=0.047). The incidence and mean volume of SEI in the SAC group (n=96) were similar to those of the simple coiling group (n=28) during the same period.

CONCLUSION

SEIs are common after NAS-assisted coiling. Their incidence in SAC was comparable to that in simple coiling. They occurred more frequently at an older age. Therefore, the use of NAS in the treatment of unruptured intracranial aneurysm does not seem to be associated with an increased risk of thromboembolic events if antiplatelet premedication has been performed well.

Endovascular treatment of middle cerebral artery aneurysms: current status and future prospects

Middle cerebral artery (MCA) aneurysms are complex and widely distributed throughout the course of the MCA. Various types of aneurysms can occur in the MCA. Ruptured as well as unruptured MCA aneurysms may require treatment to avoid bleeding or rebleeding. Currently, clipping is regarded as the first-line choice for the treatment of MCA aneurysms. However, endovascular treatment (EVT) is emerging as an alternative treatment in selected cases. EVT techniques vary. Therefore, it is necessary to review EVT for MCA aneurysms. In this review, the following issues were discussed: MCA anatomy and anomalies, classifications of MCA aneurysms, the natural history of MCA aneurysms, EVT status and principle, deployments of traditional coiling techniques and flow diverters (FDs), and deployments and prospects of intrasaccular flow disruptors and stent-like devices. According to the review and our experience, traditional coiling EVT is still the preferred therapy for most MCA aneurysms. FD deployment can be used in selective MCA aneurysms. Parent artery occlusion (PAO) can be used to treat distal MCA aneurysms. In addition, new devices can be used to treat MCA aneurysms, such as intrasaccular flow disruptors and stent-like devices. In general, EVT is gaining popularity as an alternative treatment option; however, there is still a lack of evidence regarding EVT, and longer-term data are not currently available for most EVT devices.

Anterior circulation location-specific results for stent-assisted coiling - carotid versus distal aneurysms: 1-year outcomes from the Neuroform Atlas Stent Pivotal Trial

BACKGROUND

The Neuroform Atlas Stent System is an established treatment modality for unruptured anterior and posterior circulation intracranial aneurysms. Location-specific results are needed to guide treatment decision-making. However, it is unclear whether there are differences in safety and efficacy outcomes between carotid and more distal anterior circulation aneurysms.

METHODS

The ATLAS IDE trial was a prospective, multicenter, single-arm, open-label interventional study that evaluated the safety and efficacy of the Neuroform Atlas Stent System. We compared differences in efficacy and safety outcomes of proximal internal carotid artery (ICA) versus distal and bifurcation anterior circulation aneurysms.

RESULTS

Of 182 cases, there were 70 aneurysms in the ICA and 112 in the distal anterior circulation (including ICA terminus/bifurcation). There were no significant differences in the primary efficacy endpoint (85.5% vs 83.9%, p=0.78) and complete aneurysm occlusion rates (88.7% vs 87.9%, p=0.78) between proximal ICA aneurysms and distal aneurysms, respectively. Complications were more often encountered in distal and bifurcation aneurysms, but the overall rate of major safety events was low and comparable between the two groups (1.4% vs 6.3%, p=0.14). Recanalization and retreatment rates were also similar between the groups.

CONCLUSION

The results of this study suggest that the Neuroform Atlas Stent System is a safe and efficacious treatment modality for unruptured anterior circulation intracranial aneurysms, regardless of aneurysm location.

TRIAL REGISTRATION NUMBER

NCT02340585.

Endovascular treatment of wide-necked intracranial aneurysms using the Nautilus Intrasaccular System: initial case series of 41 patients at a single center

BACKGROUND

Endovascular treatment of intracranial wide-necked and bifurcation aneurysms (WNBA) is technically challenging. The Nautilus Intrasaccular System is designed to provide a mechanical barrier at the aneurysm neck to support coil embolization. We report the results of a single-center series of patients treated for intracranial aneurysms with the Nautilus.

METHODS

Clinical and radiological data were retrospectively collected for all patients treated with the Nautilus for an unruptured or ruptured intracranial aneurysm at our center between March 2021 and March 2022. Clinical outcomes (modified Rankin Scale (mRS) scores), Raymond-Roy angiographic occlusion, recanalization, and complications were measured immediately post-procedure and at 3-6-month follow-up.

RESULTS

A total of 41 patients of mean age 56.7 years (range 37-83 years) were treated with the Nautilus, with 41 saccular aneurysms (18 (43.9%) unruptured and 23 (56.1%) ruptured). The majority of aneurysms (39/41 (95.1%)) were located in the anterior circulation. We experienced no technical complications. One patient had an asymptomatic post-procedural minor stroke related to the procedure. Immediate Class I occlusion was achieved in 30 (73.1%) patients. The rate of all-cause mortality was 7.3% (3/41). One patient was lost to follow-up. At follow-up, 94.5% (35/37) of patients achieved Class I occlusion and 94.5% (35/37) had an mRS score of 0. There were no procedural-related deaths or permanent morbidities at discharge or follow-up.

CONCLUSION

This study demonstrates good safety and effectiveness using the Nautilus Intrasaccular System to treat both ruptured and unruptured intracranial aneurysms. Larger studies are needed to confirm these findings.

Comparative analysis of long term effectiveness of Neuroform Atlas stent versus low profile visualized intraluminal stent/Woven EndoBridge devices in treatment of wide necked intracranial aneurysms

BACKGROUND

We compared the outcomes of wide necked aneurysms (WNA) treated with the Neuroform Atlas with those treated with the low profile visualized intraluminal stent (LVIS) or the Woven EndoBridge (WEB).

METHODS

Objective, prospectively collected, core laboratory adjudicated data from published trials for the Neuroform Atlas, LVIS, and WEB devices were reviewed. ATLAS (Safety and Effectiveness of the Treatment of Wide Neck, Saccular Intracranial Aneurysms With the Neuroform Atlas Stent System) study patients were included if they met other studies' inclusion criteria. Outcomes included (1) primary effectiveness (complete aneurysmal occlusion without retreatment/>50% parent vessel stenosis), (2) primary safety, (3) complete aneurysmal occlusion, and (4) retreatment rates (outcomes evaluated at the 12 month follow-up). Matching adjusted indirect comparison analysis was used to compare outcomes.

RESULTS

Analytical samples included 141 ATLAS subjects meeting WEB-IT (Woven EndoBridge Intrasaccular Therapy Study) criteria (ATLAS/WEB-IT) and 241 meeting LVIS (Pivotal Study of the Low Profile Visualized Intraluminal Support) criteria (ATLAS/LVIS). ATLAS/WEB-IT exhibited significantly higher rates of primary effectiveness and complete occlusion versus WEB (86.6% vs 53.9 %, P<0.0001, and 90.3% vs 53.9%, P<0.0001, respectively). For LVIS, there was no significant differences in primary effectiveness rates between ATLAS and LVIS (84.2% vs 77.7%, respectively, P=0.12). However, ATLAS/LVIS had a significantly higher proportion of patients achieving complete occlusion than LVIS (88.1 vs 79.1, P=0.03). Retreatment rates and primary safety outcomes were not significantly different (P>0.05) for the Atlas versus other devices except for a lower retreatment rate for ATLAS/WEB-IT versus WEB-IT (2.4% vs 9.8%, P=0.01).

CONCLUSION

The Neuroform Atlas provided higher occlusion rates and similar retreatment rates in comparable datasets compared with LVIS and WEB devices when treating WNA.

Outcomes Associated With Intracranial Aneurysm Treatments Reported as Safe, Effective, or Durable: A Systematic Review and Meta-Analysis

Importance

Testing new medical devices or procedures in terms of safety, effectiveness, and durability should follow the strictest methodological rigor before implementation.

Objectives

To review and analyze studies investigating devices and procedures used in intracranial aneurysm (IA) treatment for methods and completeness of reporting and to compare the results of studies with positive, uncertain, and negative conclusions.

Data Sources

Embase, MEDLINE, Web of Science, and The Cochrane Central Register of Clinical Trials were searched for studies on IA treatment published between January 1, 1995, and the October 1, 2022. Grey literature was retrieved from Google Scholar.

Study Selection

All studies making any kind of claims of safety, effectiveness, or durability in the field of IA treatment were included.

Data Extraction and Synthesis

Using a predefined data dictionary and analysis plan, variables ranging from patient and aneurysm characteristics to the results of treatment were extracted, as were details pertaining to study methods and completeness of reporting. Extraction was performed by 10 independent reviewers. A blinded academic neuro-linguist without involvement in IA research evaluated the conclusion of each study as either positive, uncertain, or negative. The study followed Preferring Reporting Items for Systematic Reviews and Meta-Analyses guidelines.

Main Outcomes and Measures

The incidence of domain-specific outcomes between studies with positive, uncertain, or negative conclusions regarding safety, effectiveness, or durability were compared. The number of studies that provided a definition of safety, effectiveness, or durability and the incidence of incomplete reporting of domain-specific outcomes were evaluated.

Results

Overall, 12 954 studies were screened, and 1356 studies were included, comprising a total of 410 993 treated patients. There was no difference in the proportion of patients with poor outcome or in-hospital mortality between studies claiming a technique was safe, uncertain, or not safe. Similarly, there was no difference in the proportion of IAs completely occluded at last follow-up between studies claiming a technique was effective, uncertain, or noneffective. Less than 2% of studies provided any definition of safety, effectiveness, or durability, and only 1 of the 1356 studies provided a threshold under which the technique would be considered unsafe. Incomplete reporting was found in 546 reports (40%).

Conclusions and Relevance

In this systematic review and meta-analysis of IA treatment literature, studies claiming safety, effectiveness, or durability of IA treatment had methodological flaws and incomplete reporting of relevant outcomes supporting these claims.

Use of the Neuroform Atlas stent for wide-necked cerebral aneurysms

To investigate the effect and safety of the Neuroform Atlas (NFA) stent in stent-assisted coiling of wide-necked intracranial aneurysms, patients with wide-necked intracranial aneurysms were retrospectively enrolled and treated with the NFA stent-assisted coiling. The modified Rankin scale (mRS) grades and Raymond grades were used to assess the clinical outcomes and aneurysm occlusion degrees, respectively, after embolization and at follow-up. Totally, 122 patients were enrolled with 129 wide-necked aneurysms, and forty-nine (40.2%) patients experienced subarachnoid hemorrhage. A total of 134 NFA stents were deployed in all patients. Immediately after endovascular embolization, the Raymond grade was I in 112 (86.8%), II in 8 (6.2%), and III in 9 (7.0%). Complications occurred in 7 (5.7%) patients, including stent displacement in 2 (1.6%) patients, thrombosis and cerebral infarction in 4 (3.3%), and death in 1 (0.8%). Clinical follow-up was performed in 113 (92.6%) patients 6-30 (mean 21) months after embolization, with the mRS grade 0 in 99 (87.6%) patients, 1 in 7 (6.2%), 2 in 5 (4.4%), and 3 in 2 (1.8%). Good prognosis (mRS ≤ 2) was achieved in 111 (98.2%) patients while poor prognosis (mRS > 2) in two (1.8%). Digital subtraction angiography was conducted in 98 (80.3%) patients with 104 (80.6%) aneurysms 6-30 (mean 21) months after embolization. The Raymond grade was grade I in 94 (90.4%) aneurysms, II in 4 (3.8%), and III in 6 (5.8%). Compared with the Raymond grades immediately after embolization, 93 (89.4%) aneurysms disappeared, 9 (8.7%) remained unchanged in the occlusion status, and 2 (1.9%) were recurrent. In conclusion, the NFA stent may have a high aneurysm occlusion rate and a low complication rate in assisting coiling of wide-necked intracranial aneurysms even though further studies are necessary to prove this.

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.

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.

Endovascular treatment of a supraclinoid internal carotid artery fenestration aneurysm: A case report and literature review

Supraclinoid internal carotid artery (ICA) fenestration aneurysm is rare. Except for open surgery, endovascular treatment (EVT) is considered an alternative for such an aneurysm. However, experience with this procedure is lacking. Therefore, we reported such a case. A 61-year-old woman suffered subarachnoid hemorrhage. Digital subtracted angiography (DSA) showed bilateral middle cerebral artery (MCA) aneurysms and a saccular aneurysm associated with fenestration of the supraclinoid ICA. Two MCA aneurysms were treated with single coiling, and the supraclinoid ICA fenestration aneurysm was coiled under stent assistance. The postoperative recovery was uneventful. At this time, a literature review was performed on the role of EVT in supraclinoid ICA fenestration aneurysms. A total of 13 supraclinoid ICA fenestration aneurysms treated by EVT in 11 cases, including our case, were obtained. After EVT, good outcomes were obtained in all cases. To our knowledge, this is the first study to review the role of EVT for supraclinoid ICA fenestration aneurysms. Our case report and literature review indicated that EVT for such aneurysms may be feasible and act as a therapeutic alternative.

Stretched and fractured Neuroform Atlas® stent during a stent‑assisted coil embolization: A case report

The Neuroform Atlas^® stent is one of the most recently developed stents for coil embolization, with advancements in a lower-profile delivery system, enhanced trackability, smaller cell size, and increased wall conformability. Because of these advantages, the Neuroform Atlas^® stent shows high technical success with few procedure-related complications. However, the present study reported a rare complication of a stretched and partially fractured Neuroform Atlas^® stent due to unexpected partial withdrawal of microcatheter during deployment for coil embolization of an intracranial aneurysm. The measured length of the stent was ~30 mm, which was greater than the normal length (21 mm). An additional stent was inserted into the distal part of the deployed stent to stabilize the damaged stent and remodel the aneurysm neck. This complication was considered to potentially result from the combination of several factors, including: Curved vessel; open-cell stent; unexpected microcatheter withdrawal during stent deployment; and hooking of the aneurysm selecting microcatheter with stent strut. Understanding the stent design and careful manipulation while avoiding unexpected withdrawal of the microcatheter could prevent this complication.

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.

Optional or optimal? off-label stenting for intracranial atherosclerotic stenosis: A scoping review

BACKGROUND

Intracranial atherosclerotic stenosis is a major cause of ischemic stroke. In addition to the Wingspan stent system, several self-expanding stents have been used off-label to treat intracranial atherosclerotic stenosis lesions. The purpose of this review is to assess the existing data on the off-label use of self-expanding stents in intracranial atherosclerotic stenosis, to highlight methodological limitations in current study designs, and thus providing strategies and precautions for clinical practice.

METHODS

The PubMed, EMBASE, and the Cochrane Library databases were systematically searched for relevant articles published up to April 2022. In addition to the meta analysis of Enterprise, Neuroform EZ and closed cell stent respectively, we used a narrative synthesis to summarize and discuss the appropriate strategies and precautions for the use of each stent.

RESULTS

We identified 17 studies (1091 patients with 1124 lesions) reporting 6 types of off-label self-expanding stents. The most common endpoints reported were incidence of short-term complications (range: 0-15.8%, median: 3.8%), long-term complications (range: 0-12.0%, median: 0%). Potential risks include infeasibility of stenting hard lesions or tortuous vessels, stent migration, and in-stent thrombosis. Less is known about the conditions that are appropriate for an optimal stent (e.g., open-cell, close-cell, hybrid cell). There was considerable heterogeneity across studies with regards to study populations and study designs.

CONCLUSIONS

The potential risks and benefits should be carefully considered when using off-label stents for intracranial atherosclerotic stenosis, particularly given the current evidence power. As a potential option for the Wingspan stent, based on device's approval only, a tailored approach with lesion-specific devices could be beneficial in certain patients.

The Angiographic and Clinical Follow-up Outcomes of the Wide-Necked and Complex Intracranial Aneurysms Treated With LVIS EVO-Assisted Coiling

BACKGROUND

The Low Profile Visible Intraluminal Support EVO (LVIS EVO) is a self-expandable braided stent, which was recently introduced for the treatment of intracranial aneurysms. Full visibility of the stent and a relatively high metal coverage ratio are the unique features of the LVIS EVO.

OBJECTIVE

To assess the safety, efficacy, and midterm durability of LVIS EVO stent-assisted coiling for the treatment of wide-necked intracranial aneurysms.

METHODS

The endovascular databases were reviewed to identify patients treated with LVIS EVO-assisted coiling. The technical success and immediate clinical/angiographic outcomes were assessed. Periprocedural and delayed complications were evaluated. The follow-up angiographic/clinical outcomes were investigated. The preprocedural/follow-up neurological statuses were assessed with the modified Rankin Scale.

RESULTS

One hundred three aneurysms in 103 patients (63 females) with a mean age of 54.9 ± 11.3 years were included. The mean maximum sac diameter was 6.2 ± 2.9 mm. The procedural technical success rate was 100%. Immediate postprocedural angiography showed complete occlusion in 77.7%. The mean duration of the angiographic follow-up was 8.8 ± 3.6 months. Follow-up angiography showed complete aneurysm occlusion in 89% of the 82 patients with angiographic follow-up. Recanalization was observed in 7.3% of 82 patients. Two patients (2.4%) required retreatment. In addition, 8.7% of the patients had at least 1 complication, and 2.9% of the patients developed a permanent morbidity. All patients had mRS scores ≤2.

CONCLUSION

The results of this study demonstrate that SAC with LVIS EVO is a relatively safe, efficient, and durable treatment for wide-necked and complex intracranial aneurysms.

Effect of Stent Porosity, Platelet Function Test Usage, and Dual Antiplatelet Therapy Duration on Clinical and Radiographic Outcomes After Stenting for Cerebral Aneurysms: A Meta-Analysis

BACKGROUND

The use of stents with various porosities for treating cerebral aneurysms requires dual antiplatelet therapy (DAPT) without clear guidelines on the utility of platelet function tests (PFTs) and the duration of DAPT. We sought to determine the effects of stent porosity, PFT usage, and DAPT duration on the radiographic and clinical outcomes after stenting of cerebral aneurysms.

METHODS

PubMed was searched on March 29, 2021 for studies of cerebral aneurysm stenting that had specified the stent type and DAPT duration. A random effects meta-analysis was used to measure the prevalence of nonprocedural thrombotic and hemorrhagic events, clinical outcomes, aneurysm occlusion, and in-stent stenosis stratified by stent porosity, PFT usage, and DAPT duration.

RESULTS

The review yielded 105 studies (89 retrospective and 16 prospective) with 117 stenting cohorts (50 high porosity, 17 intermediate porosity, and 50 low porosity). In the high-, intermediate-, and low-porosity stenting cohorts, PFT usage was 26.0%, 47.1%, and 62.0% and the mean DAPT duration was 3.51 ± 2.33, 3.97 ± 1.92, and 5.18 ± 2.27 months, respectively. The intermediate-porosity stents showed a reduced incidence of hemorrhagic events (π = 0.32%) compared with low-porosity stents (π = 1.36%; P = 0.01) and improved aneurysm occlusion (π = 6.18%) compared with high-porosity stents (π = 14.42%; P = 0.001) and low-porosity stents (π = 11.71%; P = 0.04). The prevalence of in-stent stenosis was lower for the intermediate-porosity (π = 0.57%) and high-porosity (π = 1.51%) stents than for the low-porosity stents (π = 3.30%; P < 0.05). PFT use had resulted in fewer poor clinical outcomes (π = 3.54%) compared with those without PFT use (π = 5.94%; P = 0.04). The DAPT duration had no effect on the outcomes.

CONCLUSIONS

In the present meta-analysis, which had selected for studies of cerebral aneurysm stenting that had reported the DAPT duration, intermediate-porosity stents and PFT use had resulted significantly improved outcomes. No effect of DAPT duration could be detected.

Rupture discrimination of multiple small (< 7 mm) intracranial aneurysms based on machine learning-based cluster analysis

BACKGROUND

Small multiple intracranial aneurysms (SMIAs) are known to be more prone to rupture than are single aneurysms. However, specific recommendations for patients with small MIAs are not included in the guidelines of the American Heart Association and American Stroke Association. In this study, we aimed to evaluate the feasibility of machine learning-based cluster analysis for discriminating the risk of rupture of SMIAs.

METHODS

This multi-institutional cross-sectional study included 1,427 SMIAs from 660 patients. Hierarchical cluster analysis guided patient classification based on patient-level characteristics. Based on the clusters and morphological features, machine learning models were constructed and compared to screen the optimal model for discriminating aneurysm rupture.

RESULTS

Three clusters with markedly different features were identified. Cluster 1 (n = 45) had the highest risk of subarachnoid hemorrhage (SAH) (75.6%) and was characterized by a higher prevalence of familiar IAs. Cluster 2 (n = 110) had a moderate risk of SAH (38.2%) and was characterized by the highest rate of SAH history and highest number of vascular risk factors. Cluster 3 (n = 505) had a relatively mild risk of SAH (17.6%) and was characterized by a lower prevalence of SAH history and lower number of vascular risk factors. Lasso regression analysis showed that compared with cluster 3, clusters 1 (odds ratio [OR], 7.391; 95% confidence interval [CI], 4.074-13.150) and 2 (OR, 3.014; 95% CI, 1.827-4.970) were at a higher risk of aneurysm rupture. In terms of performance, the area under the curve of the model was 0.828 (95% CI, 0.770-0.833).

CONCLUSIONS

An unsupervised machine learning-based algorithm successfully identified three distinct clusters with different SAH risk in patients with SMIAs. Based on the morphological factors and identified clusters, our proposed model has good discrimination ability for SMIA ruptures.

The Prophylactic Use of Glycoprotein 2b/3a Inhibitors in the Endovascular Treatment of Intracranial Aneurysms: A Systematic Review and Meta-Analysis

BACKGROUND

There has been a growing interest in the use of Glycoprotein 2b/3a (GP2B3A) inhibitors in neuroendovascular procedures. However, clinical evidence for their prophylactic use is still sparse. In this review, we aimed to assess the safety and efficacy of prophylactic GP2B3A inhibitor use and to compare the performance of GP2B3A inhibitors with oral dual antiplatelet (DAP) treatment in intracranial aneurysm patients treated with stent-assisted coil embolization or flow diversion.

METHODS

A systematic literature search was conducted in Ovid MEDLINE, Ovid Embase, Scopus, Web of Science, and Cochrane Central Register of Clinical Trials databases. Data collected included hemorrhagic and thromboembolic complication rates, mortality, good functional outcome, and rupture status. A random-effects model was fit for each outcome measure.

RESULTS

Thirteen studies comprising 1429 patients were included. The overall hemorrhagic complication rate of the GP2B3A cohort was 3.98% (95% confidence interval [CI] = 1.58-7.42). The subgroup analysis comparing ruptured versus unruptured aneurysms in which GP2B3A antagonists were used did not show a significant difference in hemorrhagic complication rates (P-value = 0.504). Compared with the DAP group, the GP2B3A inhibitor cohort had significantly lower hemorrhagic complication rates (odds ratio = 0.33; 95% CI = 0.13-0.85; P-value = 0.022). The thromboembolic complication rates were 6.63% (95% CI = 3.44-10.75) for the GP2B3A inhibitor group and 10.4% (95% CI = 7-13.8) for the DAP group. However, the difference was not statistically significant (odds ratio = 0.52; 95% CI = 0.22-1.24; P-value = 0.142).

CONCLUSIONS

Our results support that GP2B3A inhibitors are safe and effective in preventing ischemic complications associated with the endoluminal devices. Additionally, our findings indicate that GP2B3A inhibitors can be utilized as prophylactic agents regardless of the rupture status.

LVIS EVO stent-through-balloon after hydrocoil embolization of intracranial aneurysms: One-year results

BACKGROUND AND PURPOSE

To evaluate the durability and safety of complete intracranial aneurysm occlusion at one year using the low-profile braided intracranial LVIS EVO stent.

MATERIALS AND METHODS

This is a retrospective, monocentric, observational study of unruptured wide-necked intracranial aneurysms treated with the LVIS EVO stent-through-balloon technique after balloon-assisted hydrocoil embolization. Imaging and clinical data were assessed by two blinded independent neuroradiologists and neurologists, respectively. Primary endpoint was complete angiographic occlusion on day 0 and at 12 months. Secondary endpoints included clinical safety using the modified Rankin scale (mRS), ischemic and hemorrhagic adverse events, parent vessel stenosis > 50% or occlusion and retreatment rate.

RESULTS

103 aneurysms in 103 patients were included (53 years-old, 77% women). Mean aneurysm size and neck were 7 and 4 mm, respectively. Complete occlusion was 97% initially and 90% at 12 months, with pending follow up in 17.5% patients. Five patients (5%) with partially stented necks were retreated with a second stent in a T-configuration. Two stents failed to open initially and were immediately retrieved. Asymptomatic parent vessel occlusion and severe in-stent stenosis occurred in 1% and 3%, respectively. The 12-month procedure-related permanent neurological deficit and mortality rates (mRS 3-6) were 2% and 1%, respectively. There was one fatal bleeding but no large ischemic complications.

CONCLUSION

Delivering the LVIS EVO stent through a dual lumen balloon after balloon-assisted hydrocoil embolization yields a high and stable rate of complete aneurysm occlusion at one year with a reasonable immediate and delayed complication rate.

Neuroform atlas stent-assisted coiling of tiny wide-necked intracranial aneurysms

Objective

To investigate the safety and efficacy of Neuroform Atlas stent-assisted coiling for the treatment of tiny wide-necked intracranial aneurysms and evaluate risk factors associated with procedure-related complications.

Methods

We retrospectively examined 46 patients with 46 tiny wide-necked aneurysms who were treated using Atlas stent-assisted coiling at our institution from August 2020 to May 2022. Patient and aneurysm characteristics, procedural details, procedure-related complications, and angiographic and clinical outcomes were analyzed.

Results

A total of 10 patients presented with aneurysmal rupture. Atlas stent placement was successful in all patients. Angiography immediately after the procedure showed complete occlusion in 38 patients (82.6%), neck remnant in 7 (15.2%), and partial occlusion in 1 (2.2%). The mean angiographic follow-up was 8.4 months (range, 6–16). At the last follow-up, angiography showed complete occlusion in 41 patients (89.1%) and neck remnant in 5 (10.9%). No aneurysm recurrence or in-stent stenosis occurred. Incidence of procedure-related complications was 10.8% (intraprocedural aneurysm rupture, two cases; acute thrombosis, two cases; and coil migration, one case); only one patient (2.2%) experienced procedural neurological morbidity. The mean clinical follow-up was 9.7 months. A favorable outcome was achieved in 45 patients (97.8%). In univariate logistic regression analysis, aneurysm size (odds ratio, 4.538; P = 0.045) was significantly associated with procedure-related complications. However, multivariate analysis found no independent risk factors.

Conclusion

Atlas stent-assisted coiling of tiny wide-necked intracranial aneurysms is feasible and effective. Outcomes and occlusion rates are favorable and morbidity is low. The complication rate may be higher in larger tiny aneurysms.

Endovascular treatment of main trunk aneurysms in the residual anterior circulation in moyamoya disease

BACKGROUND

Main trunk aneurysms in the residual anterior circulation in moyamoya disease (MMD) are uncommon, and in such cases, endovascular treatment (EVT) is a good choice.

MATERIALS AND METHODS

A retrospective study was performed on 35 consecutive patients admitted to our hospital who were diagnosed with MMD and main trunk aneurysms in the residual anterior circulation and were treated with EVT.

RESULT

The 35 patients were aged 38-77 years (mean, 56.1 ± 8.8 years) and included 17 females (48.6%, 17/35). There were 29 cases (82.9%, 29/35) of hemorrhagic onset. In 35 patients, there were 38 main trunk aneurysms in the residual anterior circulation. Thirty-eight aneurysms underwent coiling; among them, coiling with stent assistance was used in the treatment of 6 (15.8%, 6/38) aneurysms. The immediate modified Raymond-Roy classification (MRRC) was grade I for all aneurysms. Among 35 patients, intraoperative bleeding occurred in 2 (5.7%, 2/35) patients. After EVT, immediate hemiplegia occurred in 4 (11.4%, 4/35) patients, and immediate coma occurred in 1 (2.9%, 1/35) patient. At discharge, in 35 patients, the Glasgow Outcome Scale (GOS) was five in 88.6% of them. Of 35 patients, 68.6% had follow-up data, GOS was five in 87.5% patients, and the MRRC was grade I for all aneurysms in the follow-up angiography.

CONCLUSION

For main trunk aneurysms in the residual anterior circulation in MMD, although EVT was accompanied by potential ischemic and hemorrhagic complications, which should be considered, EVT can still offer an acceptable prognosis in more than 85% of patients.

Stent-assisted coiling using the Neuroform Atlas stent for treatment of aneurysms that recur after coil embolization

Objective

To evaluate the safety and efficacy of stent-assisted coiling (SAC) using the Neuroform Atlas stent for aneurysms that recur after coil embolization.

Methods

We retrospectively reviewed patients who underwent SAC using the Neuroform Atlas stent to treat aneurysms that recurred after coil embolization from November 2020 to November 2021. Patient and aneurysm characteristics, procedural details, complications, and angiographic and clinical follow-up outcomes were recorded and analyzed.

Results

Eleven patients with 11 recurrent aneurysms were included for analysis. Atlas stent deployment was successful in all cases. Angiography immediately after the SAC procedure and at last follow-up showed complete occlusion in 10 patients (90.9%) and a residual neck in one (9.1%). Mean angiographic and clinical follow-ups were 9.2 and 10 months, respectively. A single procedure-related complication occurred, mildly blurred vision in the left eye, which recovered completely. No permanent morbidity or mortality occurred.

Conclusion

SAC using the Atlas stent to treat aneurysms that recur after coil embolization is safe and effective. Large-scale studies with long-term follow-up are warranted to confirm our results.

Endovascular treatment of aneurysms of the paraophthalmic segment of the internal carotid artery: Current status

The paraophthalmic segment of the internal carotid artery (ICA) originates from the distal border of the cavernous ICA and terminates at the posterior communicating artery. Aneurysms arising from the paraophthalmic segment represent ~5–10% of intradural aneurysms. Due to the advent of endovascular treatment (EVT) techniques, specifically flow-diverting stents (FDSs), EVT has become a good option for these aneurysms. A literature review on EVT for paraophthalmic segment aneurysms is necessary. In this review, we discuss the anatomy of the paraophthalmic segment, classification of the paraophthalmic segment aneurysms, EVT principle and techniques, and prognosis and complications. EVT techniques for paraophthalmic segment aneurysms include coil embolization, FDSs, covered stents, and Woven EndoBridge devices. Currently, coiling embolization remains the best choice for ruptured paraophthalmic segment aneurysms, especially to avoid long-term antiplatelet therapy for young patients. Due to the excessive use of antiplatelet therapy, unruptured paraophthalmic segment aneurysms that are easy to coil should not be treated with FDS. FDS is appropriate for uncoilable or failed aneurysms. Other devices cannot act as the primary choice but can be useful auxiliary tools. Both coiling embolization and FDS deployment can result in a good prognosis for paraophthalmic segment aneurysms. The overall complication rate is low. Therefore, EVT offers promising treatments for paraophthalmic segment aneurysms. In addition, surgical clipping continues to be a good choice for paraophthalmic segment aneurysms in the endovascular era.

Intracranial wide neck aneurysms: clinical and angiographic outcomes of endovascular management

Background

The treatment of intracranial wide neck aneurysms (WNAs) is usually difficult, hence several endovascular techniques were developed. This study aims to assess the clinical and angiographic imaging outcome of endovascular management of intracranial wide neck aneurysm. Forty patients were referred to the neuro-endovascular unit, at our hospital, each with a wide neck aneurysm. They were assessed regarding clinical presentation, aneurysm size, the character of the aneurysm, and the age and sex of the patient. Post-procedural, clinical, and angiographic outcomes of the patients who underwent endovascular intervention were reviewed.

Results

In this study, the mean aneurysmal neck was 5.4 ± 1.6 mm (mm). Endovascular intervention was carried out in all 40 patients in the form of simple coiling in 3 patients, double-catheter technique in 5 patients, balloon-assisted coiling (BAC) in 16 patients, stent-assisted coiling (SAC) in 13 patients, and flow diverter (FD) in 3 patients. Regarding clinical outcome, 4 patients had unfavorable outcome (the modified Rankin Scale, mRS > 2) at presentation and 3 patients at discharge. There was no unfavorable clinical outcome at 6- and 12-month follow-ups. Overall angiographic outcome at 1-year follow-up, 37/40 aneurysms (92.5%) had complete occlusion while two aneurysms had neck recurrence and one aneurysm had neck recanalization.

Conclusion

The current endovascular techniques in the treatment of WNAs are considered effective, feasible, and safe.

Treatment of wide-necked bifurcation aneurysms with the eCLIPs device: 5-year experience of a single center

BACKGROUND

The endovascular clip system (eCLIPs) is a novel device with both neck bridging and flow-diversion properties that make it suitable for the treatment of wide-necked bifurcation aneurysms.

OBJECTIVE

To describe the clinical and radiologic outcomes of the eCLIPs device, including the first-in-man use of the latest version of the device.

METHODS

This is a retrospective case series on all the wide-necked bifurcation aneurysms treated with the eCLIPs device in our center. The immediate and latest radiologic and clinical outcomes were assessed.

RESULTS

The device was successfully implanted in 12 of 13 patients. After a median follow-up period of 19 months (range 3-64 months), all patients with available data (11/12) had a good radiologic outcome (modified Raymond-Roy classification scores of 1 or 2). Two patients (18.2%) underwent re-treatment with simple coiling through the device. One of these had a subarachnoid hemorrhage prior to re-treatment. There were no major complications (death or permanent neurologic deficits) associated with use of the device.

CONCLUSION

Our series demonstrates occlusion rates that are similar to those of standard stent-assisted coiling and intrasaccular flow diversion for wide-necked bifurcation aneurysms. Larger registry-based studies are necessary to support our findings.

Application of the Neuroform Atlas Stent in Intracranial Aneurysms: Current Status

The Neuroform Atlas stent (NAS) is the successor of the Neuroform EZ stent. The NAS is compatible with a low-profile 0.0165-inch microcatheter and is soft enough to pass through small and highly tortuous vessels. The NAS can be used in treating intracranial aneurysms at almost all locations, and its use is becoming increasingly common. However, there has not yet been a complete review of NAS applications. Therefore, we performed this review, which addresses several aspects of the NAS, mainly including its characteristics, clinical trials of its application in treating aneurysms, deployment techniques for the device, the prognosis and complications of its application in treating aneurysms, and antiplatelet requirements associated with its use. Based on the evidence reviewed here, as well as our experience, we found that the NAS is a promising device for treating intracranial aneurysms, especially complex and distal aneurysms. This stent can also be used as a powerful tool to assist in rescuing coil migration, completing dual-stent reconstruction, and coiling aneurysms via a transcirculation approach. The device may require antiplatelet therapy at a lower dose and over a shorter period than other stents. The deployment of the NAS to assist in aneurysm coiling can yield good clinical outcomes and an acceptable rate of complications. Thus, the NAS is a promising device.

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.

Update on Clinical Management with Neurovascular Stents

Endovascular stenting has continued to evolve given the new trials. Several new stents have recently been developed to address specific purposes. In this focused review, we discuss the concepts of neurointerventional stents and address the clinical implications. Furthermore, each type of stent is discussed with supporting evidence for clinical utility. In the final component, we argue for continued development and utilization.

Endovascular Management of Cerebral Aneurysms of the Posterior Cerebral Artery

Purpose: To investigate the safety and efficacy of endovascular embolization of cerebral aneurysms at the P1–P3 segments of the posterior cerebral artery (PCA).

Materials and Methods: Seventy-seven patients with 77 PCA aneurysms who were treated with endovascular embolization were enrolled, including 35 (45.5%) patients with ruptured aneurysms and 42 (54.5%) with unruptured ones. The pretreatment clinical data and aneurysm occlusion status after treatment and at follow-up were analyzed.

Results: All patients were successfully treated endovascularly, including coiling alone in 10 (13.0%) patients, stent-assisted coiling in 18 (23.4%), parent artery occlusion in 25 (32.5%), and pipeline embolization device (PED) in 24 (31.2%). Complete occlusion was achieved in 48 (62.3%) aneurysms, residual neck in 4 (5.2%), and residual aneurysm in the other 25 (32.5%) at the end of embolization. Periprocedural complications occurred in eight patients, including acute thrombosis in seven (9.1%) and intraprocedural subarachnoid hemorrhage in one (1.3%), with the total complication rate of 10.4%. Follow-up was performed in 60 patients (77.9%) for 42 ± 11 months; the mRS score was 0–2 in 55 (91.7%) patients, three in four patients (6.7%), and six in one patient (1.7%). Fifty-three (88.3%) patients (53 aneurysms) had stable or complete occlusion, and seven (11.7%) patients had aneurysm recurrence or residual aneurysm. Among 19 patients treated with PED at follow-up, 15 aneurysms (78.9%) proceeded to complete occlusion while four (21.1%) aneurysms showed residual aneurysm.

Conclusion: Endovascular embolization remains a good choice of treatment with high safety and efficacy for posterior cerebral artery aneurysms.

Safety and effect of Neuroform Atlas stent in the treatment of symptomatic intracranial stenosis: A single-center experience

Background

Vascular intracranial stenosis (IS) is a significant cause of acute ischemic stroke (AIS). This single-center study aims to show that symptomatic IS treatment by using the Neuroform Atlas stent (Stryker neurovascular, Kalamazoo, MI, USA) could be effective in reducing vessel stenosis.

Methods

Ten patients affected by AIS or TIA, in the vascular territory of high-grade intracranial atherosclerotic lesions (>70% of vessel stenosis), older than 18-year-old, were treated by implanting a Neuroform Atlas stent (diameter of 4.5mm in 80% and 4mm in 20%). 70% of the patients underwent pre-stenting intracranial angioplasty.

Results

Patients were between 54.8 and 83 years old (mean 68.46y ± 8.44y), 70% males and 30% females. At admission, 50% of all patients had an AIS and 50% a TIA. Restoration of the stenotic lumen was obtained after the endovascular procedure. The percentage mean of vascular stenosis was 83.7% ± 6.09% before treatment (t0), 52.2% ± 10.42% at the end of treatment (t1) and 46.2% ± 8.28% at the follow-up (t2). The IS percentage mean reduction between t0 and t1 was 31.5% ± 7.31%, and between t1 and t2 was 6% ± 5.47%, t0 and t2 of 37.5% ± 7.38%. Percentage reduction of IS was highly significant between time t0 and t1 (p = 0.005), and t0 and t2 (p = 0.005), also with a significant reduction between t1 and t2 (p = 0.012). No patient had experienced an increase of the ischemic area in the vascular territory of the target vessel at 3 months from the initial assessment. 10% of patients experienced a 3-months negative outcome (mRS = 5), 90% experienced a favorable outcome (mRS ≤2).

Conclusions

Intracranial stenosis endovascular treatment with Neuroform Atlas stent provides encouraging results, with a statistically significant association between the vascular caliber improvement and the endovascular treatment.

Long-term follow-up of the pCONus device for the treatment of wide-neck bifurcation aneurysms

PURPOSE

Wide-neck bifurcation aneurysms remain challenging for the neurointerventionist and/or neurosurgeon despite many recent advances. The pCONus (Phenox, Bochum, Germany) is an emerging device for endovascular neck protection, we report the first long-term results of this device.

METHODS

We performed a retrospective analysis of all consecutive intracranial wide-neck bifurcation aneurysms treated with the pCONus. Patients' characteristics were reviewed, procedural complications, angiographic (Roy-Raymond scale) and clinical outcomes were documented.

RESULTS

Between January 2016 and September 2019, 43 patients (74% female, median age 56 [49-66] years) with 43 wide-neck bifurcation aneurysms (mean width of 6.8 ± 2.1 mm, dome/neck ratio of 1.3 ± 0.2 and neck of 5.2 ± 1.3 mm) were included. A procedural angiographic complication was reported in five patients (12%), no patient presented a post-operative neurological deficit or long-term complication, mortality rate was 0%. At last follow-up (median of 46.5 months [38.3-51.7]), an adequate occlusion (complete and neck remnant) was observed in 37/43 patients (86%) and an aneurysm remnant in 6/43 (14%). Four patients (9%) needed retreatment. No in-stent stenosis or branch occlusion was depicted.

CONCLUSION

pCONus device provides a safe and efficient alternative for endovascular wide-neck bifurcation aneurysms management, with long-term stability.

Multi-centric European post-market follow-up study of the Neuroform Atlas Stent System: primary results

BACKGROUND

Few prospective series have described the safety and effectiveness of the Neuroform Atlas Stent System. We aimed to investigate the efficacy and safety of the device in patients treated for unruptured aneurysm.

METHODS

ATLAS EU PMCF is a consecutive, prospective, multicentric study that included patients with unruptured saccular aneurysm of all sizes. Follow-up visits were scheduled at 3-6 months and 12-16 months with digital subtraction angiography (DSA) or MRI imaging follow-up as per the site standard of care. The primary efficacy endpoint was adequate aneurysm occlusion (Raymond Roy occlusion grade I and II) on 12 month angiography. The primary safety endpoint was any major stroke or ipsilateral stroke or neurological death within 12 months.

RESULTS

Of the 106 patients consented, 105 were treated with at least one Neuroform Atlas stent. There was a failed implantation attempt in 1 patient, 85 patients received lateral stenting, and 19 patients received Y-stenting. Mean aneurysm neck size was 4.2 mm (range 1.9-33 mm). Adequate occlusion was observed in 95.1% immediately after the procedure and in 98.9% of cases at 1 year DSA follow-up. Overall, 1.0% (1/102; 95% CI 0.0% to 5.3%) of patients experienced a primary safety endpoint of major stroke. Three minor strokes resulted in a modified Rankin Scale score of 2.

CONCLUSIONS

In this multicentric, prospective study, stent-assisted coiling of medium size unruptured aneurysms with the Neuroform Atlas stent resulted in a favorable rate of satisfactory occlusion. In our findings, the use of the Y-stenting technique was associated with increased rates of procedural complications.

CLINICAL TRIAL REGISTRATION

https://clinicaltrials.gov/ct2/show/NCT02783339.

Safety and Efficacy of Stent-Assisted Coiling of Unruptured Intracranial Aneurysms Using Low-Profile Stents in Small Parent Arteries

BACKGROUND AND PURPOSE

Stent-assisted coiling of intracranial aneurysms arising from small vessels (≤ 2.0 mm) is a common procedure. However, data regarding its treatment outcomes are scarce. This study evaluated the clinical and radiologic outcomes of stent-assisted coiling using low-profile stents for aneurysms of small parent arteries.

MATERIALS AND METHODS

From November 2015 to October 2020, sixty-four patients with 66 aneurysms arising from parent arteries of ≤2.0 mm were treated with stent-assisted coiling using a Low-Profile Visualized Intraluminal Support Junior (LVIS Jr) or the Neuroform Atlas stent in a single institution. The clinical and radiologic data were retrospectively reviewed, and the risk factors for procedure-related complications were evaluated.

RESULTS

The LVIS Jr and Neuroform Atlas stents were used in 22 (33.3%) and 44 (66.7%) cases, respectively. Technical success was achieved in 66 cases (100%). Immediate postprocedural aneurysm occlusion grades assessed by the Raymond-Roy occlusion classification were I (57.6%), II (19.7%), and III (22.7%), respectively. Procedure-related complications occurred in 10 cases (15.2%), with 8 thromboembolic complications (12.1%) and 2 hemorrhagic complications (3.0%). Procedure-related morbidity was 4.5% without mortality. On multivariate analysis, current smoking (odds ratio = 7.1, P = .021) had a statistically significant effect on procedure-related complications.

CONCLUSIONS

Stent-assisted coiling of intracranial aneurysms with low-profile stents in small vessels (≤ 2.0 mm) had a 100% success rate and a 15.2% overall complication rate with 4.5% morbidity. Current smoking was a significant risk factor associated with procedure-related complications.

Longitudinal Cost Profiles of Pipeline Embolization Device Versus Stent-Assisted Coiling in Propensity-Matched Unruptured Small Anterior Circulation Aneurysms

BACKGROUND

The cost profiles of stent-assisted coiling (SAC) vs Pipeline embolization device (PED) in small unruptured anterior circulation aneurysms have not been studied.

OBJECTIVE

To compare the 2 modalities cost profiles in a propensity-matched cohort controlling for potential technical complexity confounders including size and location.

METHODS

Patients treated with either SAC or PED at our institution were identified. Following propensity-score algorithm, 46 patients, 23 in each group were matched. The procedural and follow-up costs in each group were analyzed and compared.

RESULTS

Median maximal aneurysm size in the SAC and PED cohort were 5.3 vs 5.1 mm, respectively. Costs of access guide materials were significantly higher in the SAC group (P < .01). The average implant cost was not significantly different between the SAC and PED cohorts (${\$}$13973.2 ± ${\$}$2886.2 vs ${\$}$14,760.7 ± ${\$}$3782.1, respectively; P = .43). Similarly, total procedural costs were not different (${\$}$18341.5 ± 4104 vs ${\$}$17484.3 ± 2914.1, respectively, P = .42). Although there were significantly more total follow-ups (P = .02) and longer follow-up duration (P = .01) in SAC cohort, no significant difference in follow-up costs between the 2 groups was identified (${\$}$20557 ± ${\$}$9247 vs ${\$}$18958 ± ${\$}$9171.9, P = .56). Overall cost was similar between the SAC (${\$}$38898.9 ± ${\$}$9645.5) and PED groups (${\$}$36442.4 ± ${\$}$9076) (P = .38).

CONCLUSION

In small unruptured anterior circulation aneurysms (excluding anterior communicating artery aneurysms) matched for technical complexity confounders, SAC and PED offer an overall equivalent economic cost profile. Postprocedural noninvasive imaging was more frequent in the SAC group. However, follow-up costs and total costs were not significantly different.

Nautilus-assisted coil embolization for a complex AcomA wide-necked aneurysm in the setting of acute subarachnoid hemorrhage

Numerous devices and sophisticated strategies have been developed to further increase the number of aneurysms amenable to endovascular treatment.1-4 Despite the superfluity of available neurovascular armamentarium, wide-necked bifurcation aneurysms can still pose a significant technical challenge to the treating clinician.5-7 Neck bridging is a conceptually new approach, which provides increased occlusion rates with lower recurrence and complications rates.8-10 The Nautilus (EndoStream Medical) is an intrasaccular bridging device intended to assist in coil embolization of wide-necked cerebral aneurysms. This CE-marked device, available in various sizes, consists of flexible-layers, and is a nitinol-based, detachable implant. The device is delivered through a standard microcatheter with a minimal 0.0165" inner diameter and is fully radiopaque and completely resheathable.Owing to its unique 'tornado' like shape the device entirely reconstructs the aneurysmal neck, which facilitates the following coil embolization. In this video 1, we demonstrate the use of Nautilus - assisted coil embolization for a complex anterior communicating artery (AcomA) wide-necked aneurysm in the setting of acute subarachnoid hemorrhage.neurintsurg;neurintsurg-2021-017670v1/V1F1V1Video 1.

Neuroform Atlas Stent for Treatment of Middle Cerebral Artery Aneurysms: 1-Year Outcomes From Neuroform Atlas Stent Pivotal Trial

BACKGROUND

Heterogeneous effect of endovascular aneurysm therapy has been observed across different anatomic locations. There is a paucity of data for stent-assisted coiling of middle cerebral artery (MCA) aneurysms.

OBJECTIVE

To present the results of the MCA aneurysm group from the Neuroform Atlas (Stryker Neurovascular) investigational device exemption (IDE) trial.

METHODS

The Atlas IDE trial is a prospective, multicenter, single-arm, open-label study of wide-neck aneurysms (neck ≥ 4 mm or dome-to-neck ratio < 2) in the anterior circulation treated with the Neuroform Atlas Stent and approved coils. Follow-up was obtained immediately postprocedure and 2, 6, and 12 mo postoperatively. We herein describe safety and efficacy outcomes, and functional independence of the subjects with aneurysms from all segments of MCA.

RESULTS

A total of 35 patients were included (27 MCA bifurcation, 5 M1, 3 M2). The mean aneurysm size was 6.0 ± 1.8 mm, and the mean neck was 4.4 ± 1.2 mm. Technical procedural success was achieved in all patients. A total of 26 patients had follow-up digital subtraction angiography available at 12 mo, with 80.8% (21/26) having complete aneurysm occlusion. Twelve-month safety data were collected for 91.4% (32/35), 8.5% (3/35) had primary safety endpoint, all 3 major ischemic strokes. Mortality occurred in 2 patients beyond 30 d unrelated to procedure (1 gallbladder cancer and 1 fentanyl intoxication). At 1 yr, modified Rankin Score was 0 to 2 in 84.4% (27/32), 3 in 9.4%, and 3 patients were missing. Approximately 5.7% (2/35) of patients were retreated at 12 mo.

CONCLUSION

Stent-assisted coiling with the Neuroform Atlas Stent is a viable alternative to clipping for selected MCA aneurysms. Complete aneurysm occlusion rates have improved compared to historical data. Proper case selection can lead to acceptable endovascular results.

Pivotal trial of the Neuroform Atlas stent for treatment of posterior circulation aneurysms: one-year outcomes

BACKGROUND

Stent-assisted coiling of wide-necked intracranial aneurysms (IAs) using the Neuroform Atlas Stent System (Atlas) has shown promising results.

OBJECTIVE

To present the primary efficacy and safety results of the ATLAS Investigational Device Exemption (IDE) trial in a cohort of patients with posterior circulation IAs.

METHODS

The ATLAS trial is a prospective, multicenter, single-arm, open-label study of unruptured, wide-necked, IAs treated with the Atlas stent and adjunctive coiling. This study reports the results of patients with posterior circulation IAs. The primary efficacy endpoint was complete aneurysm occlusion (Raymond-Roy (RR) class I) on 12-month angiography, in the absence of re-treatment or parent artery stenosis >50%. The primary safety endpoint was any major ipsilateral stroke or neurological death within 12 months. Adjudication of the primary endpoints was performed by an imaging core laboratory and a Clinical Events Committee.

RESULTS

The ATLAS trial enrolled and treated 116 patients at 25 medical centers with unruptured, wide-necked, posterior circulation IAs (mean age 60.2±10.5 years, 81.0% (94/116) female). Stents were placed in all patients with 100% technical success rate. A total of 95/116 (81.9%) patients had complete angiographic follow-up at 12 months, of whom 81 (85.3%) had complete aneurysm occlusion (RR class I). The primary effectiveness outcome was achieved in 76.7% (95% CI 67.0% to 86.5%) of patients. Overall, major ipsilateral stroke and secondary persistent neurological deficit occurred in 4.3% (5/116) and 1.7% (2/116) of patients, respectively.

CONCLUSIONS

In the ATLAS IDE posterior circulation cohort, the Neuroform Atlas Stent System with adjunctive coiling demonstrated high rates of technical and safety performance.Trial registration number https://clinicaltrials.gov/ct2/show/NCT02340585.

Open-cell stent-assisted coiling for the treatment of paraclinoid aneurysms: traditional endovascular treatment is still not out of date

PURPOSE

Before we enter the era of flow diverter stents (FDS), the standard stent-assisted coiling technique is a well-established treatment option for routine paraclinoid aneurysms. We assess the clinical safety and efficacy of stent-assisted coiling with open-cell stent in the treatment of paraclinoid aneurysms and evaluate the association between clinical factors and follow-up aneurysm occlusion.

METHODS

The clinical and radiographic data of 110 consecutive patients with 122 paraclinoid aneurysms treated with open-cell stent between April 2015 and April 2019 were analyzed retrospectively at our center. We assessed the immediate and progressive occlusion rates, complications, and clinical outcome. Multivariate analysis was performed to investigate the risk factors of angiographic incomplete occlusion.

RESULTS

Among 110 patients, stent-assisted coiling was successfully performed in all cases. Four (3.6%) thromboembolic events were reported during the procedure, which resulted in transient morbidity. Immediate angiography demonstrated complete occlusion in 64 (52.5%) aneurysms and no occlusion of ophthalmic artery. Angiographic follow-up at 6 months demonstrated an increase in the complete occlusion rate to 92.9%. No delayed in-stent stenosis was observed, and three aneurysms recurred. Clinical follow-up was completed in 102 patients (92.7%), and favorable outcomes were achieved in 101 (99%) patients at 6 months. Multivariate analysis showed that aneurysm size (p < 0.001) was associated with incomplete aneurysm occlusion at follow-up.

CONCLUSION

Stent-assisted coil embolization with open-cell stents is safe and effective for the treatment of paraclinoid aneurysms and provides progressive occlusion without significant in-stent stenosis events.