Multicenter Postmarket Analysis of the Neuroform Atlas Stent for Stent-Assisted Coil Embolization of Intracranial Aneurysms

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.

An Alternative Rescue Procedure for Neuroform Atlas® Withdrawal During Deployment: A Report of Two Cases

Neuroform Atlas® (NFA; Stryker Neurovascular, Fremont, CA, USA) is a useful and safe device for the treatment of broad-necked and unruptured cerebral aneurysms. Rarely does a proximal shift of both the stent and delivery catheter occur during deployment, and it can be complex to treat. We present two cases in which an NFA that had migrated proximally during deployment was successfully retrieved. In Case 1, a left internal carotid artery (ICA) and posterior communicating artery (Pcom A) bifurcation aneurysm of 12.8 mm in maximum diameter was treated by the stent-assisted technique. An NFA stent (4 ´ 21 mm) was selected for use after placement of three coils. During deployment of the stent from the left Pcom to the ICA, withdrawal of the system in the proximal direction resulted in part of the stent falling into the aneurysm. The half-released stent was retrieved carefully because we considered that complete deployment of the stent would result in inadequate treatment and fatal consequences in the long term. After Case 1, an experiment was conducted to determine whether it was safe to retrieve the NFA into the parent catheter. In Case 2, we experienced the same situation during the procedure of an anterior communicating artery aneurysm. Based on the experience of Case 1, we were able to perform stent retrieval in Case 2 without hesitation. The sudden withdrawal of an NFA stent can occur during the placement procedure. If surgeons encounter proximal migration during NFA deployment, retrieval of the NFA may be an option.

Stable and Thin-Polymer-Based Modification of Neurovascular Stents with 2-Methacryloyloxyethyl Phosphorylcholine Polymer for Antithrombogenicity

The advent of intracranial stents has revolutionized the endovascular treatment of cerebral aneurysms. The utilization of stents has rendered numerous cerebral aneurysm amenable to endovascular treatment, thereby obviating the need for otherwise invasive open surgical options. Stent placement has become a mainstream approach because of its safety and efficacy. However, further improvements are required for clinically approved devices to avoid the frequent occurrence of thrombotic complications. Therefore, controlling the thrombotic complications associated with the use of devices is of significant importance. Our group has developed a unique stent coated with a 2-methacryloyloxyethyl phosphorylcholine (MPC)-based polymer. In this study, the surface characteristics of the polymer coating were verified using X-ray photoelectron spectroscopy and atomic force microscopy. Subsequently, the antithrombotic properties of the coating were evaluated by measuring platelet count and thrombin-antithrombin complex levels of whole human blood after 3 h of incubation in a Chandler loop model. Scanning electron microscopy was utilized to examine thrombus formation on the stent surface. We observed that MPC polymer-coated stents significantly reduced thrombus formation as compared to bare stents and several clinically approved devices. Finally, the coated stents were further analyzed by implanting them in the internal thoracic arteries of pigs. Angiographic imaging and histopathological examinations that were performed one week after implantation revealed that the vascular lumen was well maintained and coated stents were integrated within the vascular endothelium without inducing adverse effects. Thus, we demonstrated the efficacy of MPC polymer coating as a viable strategy for avoiding the thrombotic risks associated with neurovascular stents.

Stent coating containing a charged silane coupling agent that regulates protein adsorption to confer antithrombotic and cell-adhesion properties

The evolution of endovascular therapies, particularly in the field of intracranial aneurysm treatment, has been truly remarkable and is characterized by the development of various stents. However, ischemic complications related to thrombosis or downstream emboli pose a challenge for the broader clinical application of such stents. Despite advancements in surface modification technologies, an ideal coating that fulfills all the desired requirements, including anti-thrombogenicity and swift endothelialization, has not been available. To address these issues, we investigated a new coating comprising 3-aminopropyltriethoxysilane (APTES) with both anti-thrombogenic and cell-adhesion properties. We assessed the anti-thrombogenic property of the coating using an in vitro blood loop model by evaluating the platelet count and the level of the thrombin-antithrombin (TAT) complex, and investigating thrombus formation on the surface using scanning electron microscopy (SEM). We then assessed endothelial cell adhesion on the metal surfaces. In vitro blood tests revealed that, compared to a bare stent, the coating significantly inhibited platelet reduction and thrombus formation; more human serum albumin spontaneously adhered to the coated surface to block thrombogenic activation in the blood. Cell adhesion tests also indicated a significant increase in the number of cells adhering to the APTES-coated surfaces compared to the numbers adhering to either the bare stent or the stent coated with an anti-fouling phospholipid polymer. Finally, we performed an in vivo safety test by implanting coated stents into the internal thoracic arteries and ascending pharyngeal arteries of minipigs, and subsequently assessing the health status and vessel patency of the arteries by angiography over the course of 1 week. We found that there were no adverse effects on the pigs and the vascular lumens of their vessels were well maintained in the group with APTES-coated stents. Therefore, our new coating exhibited both high anti-thrombogenicity and cell-adhesion properties, which fulfill the requirements of an implantable stent.

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.

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.

Aneurysmal recurrence and retreatment modalities after Woven EndoBridge (WEB) device implantation: A systematic review and meta-analysis

BACKGROUND

The Woven EndoBridge (WEB) device is used to treat wide-neck bifurcation aneurysms (WNBAs). We conducted a systematic review and meta-analysis to determine the retreatment rate strategies following aneurysmal recurrence of WEB device treated WNBAs.

METHODS

This study is reported following the PRISMA 2020 guidelines. We conducted a systematic review of the literature using PubMed, Scopus, Embase, and Web of Science. Data were pooled using a random-effects model. We calculated pooled prevalence and corresponding 95% confidence intervals (CI).

RESULTS

We included 11 studies. The overall retreatment rate was 171/1875 aneurysms (10.3%; 95% CI  =  8.3-12.9). Stent-assisted coiling was used to treat 59 aneurysms (36.7%; 95% CI  =  26.4-48.5), and flow diverters were used to treat 44 aneurysms (18.7%; 95% CI  =  9.9-32.5). Following retreatment, the complete occlusion rate was 57/91 aneurysms (62.8%; 95% CI  =  48.2-75.3) and the adequate occlusion rate was 24/91 aneurysms (26.4%; 18.4%-36.4%). The most common aneurysmal recurrence site was the anterior communicating artery (44/136 aneurysms, 32.4%; 95% CI  =  25.0-40.7).

CONCLUSIONS

Roughly 10% of WNBAs initially treated with the WEB device will undergo retreatment. Retreatment is an effective strategy for WEB-treated aneurysms, with high rates of adequate and complete occlusion. Future studies should work to identify risk factors for aneurysmal recurrence.

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.

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.

Kissing Aneurysms of the Posterior Inferior Cerebellar Artery Treated by Anchor Coil Technique and Stenting from the Contralateral Side: A Case Report

Kissing aneurysms refer to the condition in which two cerebral aneurysms with separate necks are in contact with each other. At present, there is scarce information on kissing aneurysms occurring near the vertebral artery (VA)-posterior inferior cerebellar artery (PICA). We report the first case of VA-PICA and nonbranched PICA kissing aneurysms, which were successfully treated with contralateral stenting after the anchor coil technique using two microcatheters. A 64-year-old woman was diagnosed with a left VA-PICA aneurysm (5.5 mm) and an adjacent small PICA aneurysm (2.5 mm) with the aneurysmal walls in close contact. For stenting, microcatheters were navigated to the PICA from the contralateral side, and framing coils for the anchor were placed into each aneurysm from the ipsilateral side. Next, a Neuroform Atlas stent was deployed from the PICA to the distal side of the VA, and coiling was completed using the jailing technique. The patient had a good postoperative course, and a left vertebral angiogram revealed complete occlusion of both aneurysms after 6 months. Adequate surgical planning and application of an appropriate stent-assisted coil embolization technique contributed to the success of the procedure in this rare case.

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.

Risk Factors for Recurrence of Intracranial Aneurysm After Coil Embolization: A Meta-Analysis

Intracranial aneurysm is a severe cerebral disorder involving complicated risk factors and endovascular coiling is a common therapeutic selection for intracranial aneurysm. The recurrence is a clinical challenge in intracranial aneurysms after coil embolization. With this study, we provided a meta-analysis of the risk factors for the recurrence of intracranial aneurysm after coil embolization. Nine studies were included with a total of 1,270 studies that were retrieved from the database. The sample size of patients with intracranial aneurysms ranged from 241 to 3,530, and a total of 9,532 patients were included in the present meta-analysis. The intracranial aneurysms that occurred in middle cerebral artery (MCA) (OR = 1.09, 95% CI: 1.03–1.16, P = 0.0045) and posterior circulation (OR = 2.01, 95% CI: 1.55–2.60, P = 0.000) presented the significantly higher risk of recurrence after coil embolization. Meanwhile, intracranial aneurysms of size > 7 mm (OR = 5.38, 95%CI: 3.76–7.70, P = 0.000) had a significantly higher risk of recurrence after coil embolization. Moreover, ruptured aneurysm (OR = 2.86, 95% CI: 2.02–4.04, P = 0.000) and subarachnoid hemorrhage (SAH) (OR = 1.57, 95% CI: 1.20–2.06, P = 0.001) was positively correlated with the risk of recurrence after coil embolization. In conclusion, this meta-analysis identified the characteristics of intracranial aneurysms with MCA, posterior circulation, size > 7 mm, ruptured aneurysm, and SAH as the risk factors of recurrence after coil embolization for intracranial aneurysms.

Retreatment of Residual and Recurrent Aneurysms After Embolization With the Woven EndoBridge Device: Multicenter Case Series

BACKGROUND

The Woven EndoBridge (WEB) device (Terumno Corp. [parent company of Microvention]) was approved by the U.S. Food and Drug Administration as the first intrasaccular device for intracranial aneurysm treatment in December 2018. Its use has become more common since then, but both trial results and postmarket experiences have raised questions about the efficacy in achieving complete aneurysm obliteration. Retreatment after WEB embolization has not been extensively discussed.

OBJECTIVE

To discuss the incidence and retreatment of aneurysms after initial WEB embolization.

METHODS

Retrospective review across 13 institutions identified all occurrences of WEB retreatment within neurovascular databases. Details regarding demographics, aneurysm characteristics, treatment considerations, clinical outcomes, and aneurysm occlusion were obtained and analyzed.

RESULTS

Thirty aneurysms were retreated in 30 patients in a cohort of 342 WEB-treated aneurysms. The retreatment rate was 8.8%. Endovascular methods were used for 23 cases, and 7 were treated surgically. Two aneurysms presented with rehemorrhage after initial WEB embolization. Endovascular treatments included stent-assisted coiling (12), flow diversion (7), coiling (2), PulseRider (Johnson & Johnson)-assisted coiling (1), and additional WEB placement (1). Surgical treatments included primary clipping (6) and Hunterian ligation (1). There were no major complications within the study group.

CONCLUSION

WEB retreatments were successfully performed by a variety of techniques, including stent-assisted coiling, clipping, and flow diversion as the most common. These procedures were performed safely with subsequent obliteration of most aneurysms. The potential need for retreatment of aneurysms should be considered during primary WEB treatments.

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.

Antiplatelet therapy for standalone coiling of ruptured intracranial aneurysms: a systematic review and meta-analysis

BACKGROUND

Endovascular embolization using standalone coils is the preferred treatment option for ruptured cerebral aneurysms to avoid the use of dual antiplatelet therapy with stent coiling or endoluminal flow diversion devices. However, it has been reported that patients undergoing the standalone coiling approach are at risk for periprocedural thromboembolism. Therefore, this systematic review and meta-analysis was performed to clarify the risks and benefits of antiplatelet therapy (AT) during coiling procedures performed to treat ruptured aneurysms, including the incidence of early thromboembolic events, hemorrhagic and delayed ischemic events, as well as clinical outcomes.

METHODS

A comprehensive search of three databases was performed for articles from inception to June 2021. After fulfilling the inclusion criteria, five studies were included in this meta-analysis and 462 patients with aneurysmal subarachnoid hemorrhage (aSAH) were identified who underwent endovascular standalone coiling treatment. Aneurysm location, patient characteristics, and aSAH grades were comparable between the AT and non-AT groups.

RESULTS

AT significantly decreased the incidence of thromboembolic events immediately after the coiling procedures compared with non-AT (OR 3.42; 95% CI 1.77 to 6.61, p<0.001). The incidences of hemorrhage, delayed ischemia, and clinical outcomes with or without AT were not significantly different between groups.

CONCLUSIONS

Although this study showed no beneficial effect of AT on clinical outcomes, the results suggest that AT could be combined with standalone coiling to avoid thromboembolism during the perioperative period. A large prospective study and/or an additional meta-analysis would be required to further investigate how AT benefits standalone coil embolization in aSAH.

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.

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

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

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

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

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

Transcirculation approach for stent-assisted coiling of intracranial aneurysms: a multicenter study

BACKGROUND

The transcirculation approach (TCA) for stent-assisted coiling (SAC) of intracranial aneurysms may be useful for certain wide-neck bifurcation aneurysms as well as those with acute-angle efferent branches.

OBJECTIVE

To describe a multicenter experience using the TCA for SAC.

METHODS

A multicenter, retrospective study (2016-2020) of aneurysm treatment using SAC via the TCA. Angiographic outcome was scored using the Raymond Scale (adequate occlusion 1 and 2), and clinical outcome was scored using a modified Rankin Scale (good outcome 0-2) RESULTS: Twenty-nine patients with 29 aneurysms were included (62.1% female; average age 61; 89.7% unruptured; 13.8% previously treated; average dome size 6.4 mm; average neck 4.4 mm). Aneurysm locations included internal carotid artery-fetal posterior cerebral artery (n=4), internal carotid artery terminus (n=4), anterior communicating artery (n=8), vertebral artery-posterior inferior cerebellar artery (n=2), and basilar tip (n=11). The TCA used communicating arteries (93.1%; average 1.6 mm), intermediate catheters (51.7%), jailing technique (62.1%), and staged procedures (10.3%). The most common stent was the Neuroform Atlas (Stryker; 69%). Immediate adequate occlusion was obtained in 75.9%, and five patients with inadequate occlusion progressed to adequate occlusion at follow-up. One (3.4%) procedural complication occurred: a watershed stroke in the setting of baseline four-vessel extracranial disease. Two patients had a poor outcome unrelated to the TCA. The majority of patients (86.4%) had a good clinical outcome. One case of in-stent stenosis due to non-compliance with medication was seen, which resolved with medication resumption.

CONCLUSIONS

The TCA for SAC can be performed for a variety of aneurysms with a low complication rate and good clinical outcomes.