The LVIS Jr. microstent to assist coil embolization of wide-neck intracranial aneurysms: clinical study to assess safety and efficacy

Comparison of LVIS and Enterprise stent-assisted coiling embolization for ruptured intracranial aneurysms: a propensity score-matched cohort study

The role of a low-profile visualized intraluminal support stent (LVIS) and Enterprise in the treatment of unruptured intracranial aneurysms is well established. Although previous studies have investigated one single type of stent for the treatment of ruptured intracranial aneurysms (RIA), the safety and efficacy between the two types of stents has not been fully explored. Herein we conducted a study to compare the outcomes of the two stents for treatment of RIA. This is a prospective registry database of aneurysmal subarachnoid hemorrhage (aSAH) patients admitted to a single institution between 2018 and 2021. We collected patient baseline information, secondary complications, follow-up angiographic data, long-term prognostic outcomes, and conducted propensity score matching (PSM) analysis with 1:1 ratio and a multivariable logistic regression to compare the outcomes of the two types of stents. A total of 231 patients with RIAs were included in this study, with 108 treated using the LVIS device and 123 treated using the Enterprise device. Before PSM analysis, only the incidence of poor prognosis after 12 months was higher in the Enterprise group comparing to the LVIS group (20% vs. 10%, P = 0.049). After PSM analysis, there was a higher occurrence of delayed cerebral ischemia (DCI) in the Enterprise group compared to the LVIS group (odds ratio [OR] 3.95, 95% confidence interval [CI] [1.20-13.01], P = 0.024). However, no significant difference in prognosis was observed after PSM adjustment. Furthermore, subgroup analysis revealed that patients with female (P = 0.019), hypertension (P = 0.048), and anterior circulation aneurysms (P = 0.019) receiving the Enterprise device had a higher risk of DCI. The overall efficacy of LVIS and Enterprise in the treatment of RIA is comparable, while the incidence of DCI in the LVIS group is lower than that in the Enterprise group after PSM analysis. Registration number: NCT05738083 ( https://clinicaltrials.gov/ ).

"Stent-within-a-Stent" technique for the endovascular treatment of giant aneurysm of basilar artery bifurcation: A case report

Stents have become very important devices in the treatment of intracranial aneurysms. Flow diverters as high metal coverage stents are developed for hemodynamic treatment of challenging intracranial aneurysms. High level of metal coverage can also be achieved by implementing regular stents telescopically one in another. We present the case of a patient successfully treated for giant aneurysm of basilar artery bifurcation by a "Stent-within-a-Stent" technique. After stent implantation, coil embolization was performed using multiple-sized platinum helical coils. Control angiography performed at the end of the procedure revealed aneurysm occlusion. After 3 years, the patient is fully neurologically recovered, without pyramidal deficit, independently active and able to work.

Efficacy and safety of low profile stents in Y-stent assisted coil embolization of wide-necked bifurcation aneurysms: a systematic review and meta-analysis

Low-profile stents may provide significant advantages in Y-stent-assisted coiling due to their miniaturized design and capability to be delivered through a 0.0165-inch microcatheter. We aim to investigate the safety and efficacy of using these newer versions of stents in Y-stent-assisted coiling for the treatment of wide-necked bifurcation aneurysms. We conducted a systematic review of the PubMed, Embase, Cochrane Library, and Web of Science databases up to September 2023, following the PRISMA guidelines. Eligible studies included  ≥ 5 patients with intracranial wide-necked bifurcation aneurysms treated with Y-stent-assisted coiling using low-profile stents, providing angiographic and clinical outcomes. Two authors independently handled the search and selection. Primary outcomes were immediate and follow-up aneurysm occlusion, procedure-related complications, aneurysm recanalization, and retreatment. Secondary outcomes included technical success, procedure-related morbidity, procedure-related mortality, procedure-related stroke, and in-stent stenosis at follow-up. We analyzed the data using random-effects meta-analysis. In total, 19 studies including 507 patients with 509 aneurysms were included. 95% of the treated aneurysms were managed using the crossing Y-configuration. Technical success rate was 99%. Immediate adequate aneurysm occlusion was 90%. Follow-up angiographies were available for 443 aneurysms. The mean angiographic follow-up duration was 15.6 ± 1.9 months. The rates for follow-up adequate aneurysm occlusion and complete occlusion were 98% and 89%, respectively. After a mean clinical follow-up of 15 ± 2.4 months, a good clinical outcome was observed in 98% of patients. Overall, procedure-related morbidity and mortality rates were 1.3%, and 0.4%, respectively. Low-profile stents in Y-stent-assisted coiling outperform previous stent versions in terms of safety, efficacy, and technical success rates.

Intracranial aneurysms treated with stent-assisted coil embolization: evaluation with four-dimensional ultrashort-TE MR angiography

OBJECTIVES

As a novel follow-up method for intracranial aneurysms treated with stent-assisted coil embolization (SACE), we developed four-dimensional magnetic resonance angiography (MRA) with minimized acoustic noise utilizing ultrashort-echo time (4D mUTE-MRA). We aimed to assess whether 4D mUTE-MRA is useful for the evaluation of intracranial aneurysms treated with SACE.

METHODS

This study included 31 consecutive patients with intracranial aneurysm treated with SACE who underwent 4D mUTE-MRA at 3 T and digital subtraction angiography (DSA). For 4D mUTE-MRA, five dynamic MRA images with a spatial resolution of 0.5 × 0.5 × 0.5 mm3 were obtained every 200 ms. Two readers independently reviewed the 4D mUTE-MRA images to evaluate the aneurysm occlusion status (total occlusion, residual neck, and residual aneurysm) and the flow in the stent using a 4-point scale (from 1 [not visible] to 4 [excellent]). The interobserver and intermodality agreement was assessed using κ statistics.

RESULTS

On DSA images, 10 aneurysms were classified as total occlusion, 14 as residual neck, and 7 as residual aneurysm. In terms of aneurysm occlusion status, the intermodality and interobserver agreement was excellent (κ = 0.92 and κ = 0.96, respectively). For the flow in the stents on 4D mUTE-MRA, the mean score was significantly higher for single stents than multiple stents (p < .001) and for open-cell type stents than closed-cell type (p < .01).

CONCLUSIONS

4D mUTE-MRA is a useful tool with a high spatial and temporal resolution for the evaluation of intracranial aneurysms treated with SACE.

KEY POINTS

• In the evaluation of intracranial aneurysms treated with SACE on 4D mUTE-MRA and DSA, the intermodality and interobserver agreement in aneurysm occlusion status was excellent. • 4D mUTE-MRA shows good to excellent visualization of flow in the stents, especially for cases treated with a single or open-cell stent. • 4D mUTE-MRA can provide hemodynamic information related to embolized aneurysms and the distal arteries to stented parent arteries.

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.

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.

Safety, Efficacy, and Durability of Stent-Assisted Coiling Treatment of M2 (Insular) Segment MCA Aneurysms

BACKGROUND AND PURPOSE

Most distal MCA aneurysms are located within the insular segment, which lies between the limen insulae and circular sulcus. However, experience is limited in the microsurgical and endovascular management of insular segment MCA aneurysms. In this multicenter retrospective case series, we aimed to investigate the safety, efficacy, and durability of stent-assisted coiling for treatment of insular segment MCA aneurysms.

MATERIALS AND METHODS

A retrospective review was performed to identify patients with insular MCA aneurysms that were treated with stent-assisted coiling. The technical success of the procedures and the initial and follow-up clinical and angiographic outcomes were assessed. Periprocedural and delayed complications were reviewed.

RESULTS

Twenty-seven aneurysms in 27 patients with a mean age of 53.3 (SD,11.3) years were included. The mean size of the aneurysms was 6.3 (SD 2.6) mm. Endovascular procedures were successfully performed in all patients. Immediate postprocedural angiography revealed complete aneurysm occlusions in 81.5%. Periprocedural complications developed in 7.4% without causing permanent morbidity. A delayed thromboembolic complication resulted in a minor permanent morbidity in 1 patient (3.7%). There was no mortality. The mean duration of angiographic follow-up was 19.5 (SD, 9.8)  months. The last follow-up examinations showed complete occlusion in 92.6%. During the follow-up period, none of the treated aneurysms showed recanalization.

CONCLUSIONS

The results of this study demonstrate that stent-assisted coiling with a low-profile self-expandable stent is a feasible and relatively safe technique for endovascular treatment of insular segment complex MCA aneurysms. Additionally, it provides an effective and durable treatment for insular MCA aneurysms.

Usefulness of Silent MRA for Evaluation of Aneurysm after Stent-Assisted Coil Embolization

OBJECTIVE

To determine the usefulness of Silent MR angiography (MRA) for evaluating intracranial aneurysms treated with stent-assisted coil embolization.

MATERIALS AND METHODS

Ninety-nine patients (101 aneurysms) treated with stent-assisted coil embolization (Neuroform atlas, 71 cases; Enterprise, 17; LVIS Jr, 9; and Solitaire AB, 4 cases) underwent time-of-flight (TOF) MRA and Silent MRA in the same session using a 3T MRI system within 24 hours of embolization. Two radiologists independently interpreted both MRA images retrospectively and rated the image quality using a 5-point Likert scale. The image quality and diagnostic accuracy of the two modalities in the detection of aneurysm occlusion were further compared based on the stent design and the site of aneurysm.

RESULTS

The average image quality scores of the Silent MRA and TOF MRA were 4.38 ± 0.83 and 2.78 ± 1.04, respectively (p < 0.001), with an almost perfect interobserver agreement. Silent MRA had a significantly higher image quality score than TOF MRA at the distal internal carotid artery (n = 57, 4.25 ± 0.91 vs. 3.05 ± 1.16, p < 0.001), middle cerebral artery (n = 21, 4.57 ± 0.75 vs. 2.19 ± 0.68, p < 0.001), anterior cerebral artery (n = 13, 4.54 ± 0.66 vs. 2.46 ± 0.66, p < 0.001), and posterior circulation artery (n = 10, 4.50 ± 0.71 vs. 2.90 ± 0.74, p = 0.013). Silent MRA had superior image quality score to TOF MRA in the stented arteries when using Neuroform atlas (4.66 ± 0.53 vs. 3.21 ± 0.84, p < 0.001), Enterprise (3.29 ± 1.59 vs. 1.59 ± 0.51, p = 0.003), LVIS Jr (4.33 ± 1.89 vs. 1.89 ± 0.78, p = 0.033), and Solitaire AB stents (4.00 ± 2.25 vs. 2.25 ± 0.96, p = 0.356). The interpretation of the status of aneurysm occlusion exhibited significantly higher sensitivity with Silent MRA than with TOF MRA when using the Neuroform Atlas stent (96.4% vs. 14.3%, respectively, p < 0.001) and LVIS Jr stent (100% vs. 20%, respectively, p = 0.046).

CONCLUSION

Silent MRA can be useful to evaluate aneurysms treated with stent-assisted coil embolization, regardless of the aneurysm location and type of stent used.

Dual Stenting with New-Generation Stents for Aneurysm Embolization in Acute Subarachnoid Hemorrhage

OBJECTIVE

Endosaccular treatment is the backbone of endovascular treatment for acutely ruptured aneurysms. Stent-assisted coiling is a niche technique in this context. Data on X-stenting or Y-stenting (dual crossing stenting, DCS) in the acute phase after subarachnoid hemorrhage (aSAH) are scarce, and the impact of stent properties on the outcome is unknown. We retrospectively evaluated the clinical and imaging results of DCS in patients treated for aSAH.

METHODS

Patients with aSAH treated with DCS were evaluated retrospectively. Patient and procedural characteristics were evaluated to determine clinical outcomes, associated complications, and follow-up imaging findings.

RESULTS

Sixteen procedures (16 patients; 10 women, mean age 55.8) were performed within 3.2 ± 2.6 days (range 1-10 days) of aSAH. Only the latest generation of intracranial stents (dual Neuroform Atlas-12 cases, dual Leo Baby-2 cases, Neuroform Atlas with Acclino Flex, or Leo Baby-2 cases) were used. Technical success rate was 100%; however, 25% of the procedures were complicated, leading to adverse events in 3 procedures (18.8%; 2 stent thrombosis, 1aneurysm rupture). Procedure-related morbidity and mortality and overall permanent morbidity and mortality were 6.3%, none, 6.3%, and 12.5%, respectively. No additional neurologic events were noted on a mean clinical follow-up of 160 ± 156 (range: 1-540) days.

CONCLUSIONS

Our findings and the patient-by-patient data we extracted from the literature suggest that DCS can be performed with new-generation, low-profile stents in aSAH if a definite procedural risk is acceptable for a specific patient. New-generation open-cell stent combinations appear as a viable choice for DCS in aSAH.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Low-Profile Visualized Intraluminal Support Jr Braided Stent Versus Atlas Self-Expandable Stent for Treatment of Intracranial Aneurysms: A Single Center Experience

BACKGROUND

The Neuroform Atlas Stent and Low-profile Visualized Intraluminal Support (LVIS) and LVIS Jr stents are used to treat intracranial aneurysms (IAs), but their safety, performance, and outcomes have not been directly compared.

OBJECTIVE

To compare the technical performance and outcomes of Atlas and LVIS Jr stents for treatment of IAs.

METHODS

IAs treated by stent-assisted coiling using an Atlas (Stryker, Kalamazoo, Michigan) or LVIS Jr (MicroVention, Aliso Viejo, California) device between January 2014 to November 2019 were retrospectively evaluated. Patient demographics, aneurysm size and location, technical difficulties, and clinical and angiographic follow-up were analyzed.

RESULTS

A total of 116 patients, (mean age 64.2 ± 11.8 yr, 72.7% female) with 121 aneurysms underwent stent-assisted coiling with deployment of Atlas (n = 64) or LVIS Jr (n = 57) stents. Mean aneurysm size was 6.2 ± 2.7 mm. Immediate rates of Raymond-Roy (RR) 1/2 were 89.0% (57/64) and 80.7% (46/57) for the Atlas and LVIS Jr groups, respectively. Neither group had major postoperative thromboembolic complications; however, 15.8% (9/57) of the LVIS Jr procedures had technical issues. Additionally, 88.5% (46/52) and 91.2% (33/36) of patients in the Atlas and LVIS Jr groups had RR 1/2 at a mean follow-up of 13.6 and 18.7 mo, respectively.

CONCLUSION

Treatment of IAs with Atlas and LVIS Jr stents results in favorable clinical outcomes and angiographic results at follow-up, with low rates of recurrence and retreatment, suggesting both devices are safe and effective. Notably, LVIS Jr had more technical problems than Atlas.

Clinical and angiographic outcomes of stent-assisted coiling of paraclinoid aneurysms: Comparison of LVIS and Neuroform stents

Paraclinoid aneurysms are mainly intradural, and are associated with a potential risk of subarachnoid hemorrhage (SAH). The application of stent-assisted coiling has been widely used in endovascular treatment of intracranial aneurysms. Here we aimed to compare clinical outcomes between low-profile visualized intraluminal support stents (LVIS) and Neuroform (NU) stents. Between January 2013 and December 2017, a total of 101 patients with 118 unruptured paraclinoid aneurysms were embolized by LVIS or NU stents. Procedure-related complications, angiography, and follow-up results were retrospectively analyzed. A total of 45 patients with 54 aneurysms received LVIS stents, and 56 patients with 64 aneurysms received NU stents. Procedure-related complication rate was 6.7% in the LVIS group and 5.4% in the NU group, with no statistical differences between groups (P = 0.511). Compared with the NU group, greater initial complete or near-complete aneurysm obliteration was achieved in the LVIS group (79.6% vs 59.4%, P = 0.0192). DSA angiography follow-up imaging of the 118 aneurysms showed that the LVIS group increased in Raymond-Roy Grade Scale I (RRGS I), however there is no statistical difference (P = 0.32). Compared with NU stents, LVIS stents may achieve greater complete or near-complete occlusion rate immediately post-operation. However, there was no difference in procedural-related complications and follow-up outcomes between LVIS and NU stent groups.

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

BACKGROUND AND PURPOSE

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

MATERIALS AND METHODS

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

RESULTS

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

CONCLUSIONS

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

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

OBJECTIVE

The Neuroform Atlas (Stryker Neurovascular, Fremont, CA, USA) is a low-profile laser cut self-expanding nitinol stent designed to provide coil support and wall apposition during aneurysm embolisation. In this study, we performed a meta-analysis of outcomes after treatment with the Neuroform Atlas stent for the purpose of coil embolisation.

METHODS

The primary objectives of this meta-analysis were to define the safety (treatment-related complications, neurologic outcomes, mortality rate) and the efficacy (aneurysm occlusion rate) of the treatment of intracranial aneurysms with the Neuroform Atlas stent. A systematic review and meta-analysis was performed by searching PubMed, EMBASE, and the Cochrane CENTRAL Library for all published studies on the treatment of intracranial aneurysms with the Neuroform Atlas device up to 6 April 2020. The review was prepared in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines.

RESULTS

A total of 14 studies were analysed (577 patients with 593 intracranial aneurysms). The mean age was 58.2 years and 35.6% were male. Technical success of the procedure was 100%. RROC1/RROC2 (Raymond-Roy occlusion classification (RROC) 1/2) (total occlusion/neck remnant) at a mean follow-up of 8.9 months was achieved in 94.8%. RROC3 was 4.9%. All-cause mortality was 1.8% and permanent residual neurological deficit or disability was 2.7%. Overall complications at follow-up were 6.2%.

CONCLUSION

Our analysis demonstrated good rates of occlusion at follow-up for aneurysms treated with the Atlas device at follow-up. The safety profile appears similar to other low-profile intracranial stents.

Endovascular treatment of patients with intracranial aneurysms: feasibility and successful employment of a new low profile visible intraluminal support (LVIS) EVO stent

BACKGROUND AND PURPOSE

Low-profile self-expandable stents have increased the number of intracranial aneurysms treated by endovascular means. The new low-profile visible intraluminal support device LVIS EVO (Microvention), the successor of LVIS Jr, is a self-expandable and retrievable microstent system, designed for implantation into intracranial arteries with a diameter up to 2.0 mm. In this retrospective study we aimed to elucidate the technical feasibility and clinical safety of the novel LVIS EVO stent for stent-assisted coil embolisation of intracranial aneurysms.

MATERIALS AND METHODS

A single centre technical report of the first six consecutive cases of stent-assisted coil embolisation with the novel LVIS EVO stent for the treatment of unruptured or recanalised intracranial aneurysms. Records were made of basic demographics, aneurysmal characteristics, device properties and related technical details, adverse events, clinical outcomes and occlusion rates on available radiological follow-up.

RESULTS

Six LVIS EVO devices were successfully implanted in all subjects to treat a total number of six intracranial aneurysms. No device-related intraprocedural complications were seen. At early clinical follow-up six out of six (100%) patients had a modified Ranking score of 0-1. Early angiographic and cross-sectional radiological follow-up, available in five out of six (83.3%) of the patients confirmed unchanged aneurysmal occlusion rates. A minor, transitory neurological deficit was recorded in one of the six (16.6%) patients. Mortality was 0%.

CONCLUSIONS

Preliminary experience in this subset of our patients confirms a notably improved technical behaviour of the novel LVIS EVO stent system when compared to its ancestor LVIS Jr. The enhanced visibility of the stent and the refined delivery/retrieval capabilities of the stent further increase the safety margins of the devices profile, especially in cases of tortuous anatomy.

Stent-Assisted Coiling of Unruptured MCA Aneurysms Using the LVIS Jr. Device: A Multicenter Registry

Purpose: The low-profile visualized intraluminal support junior (LVIS Jr.) is a new generation low-profile braided stent. Our aim was to evaluate the safety and efficacy of the LVIS Jr. in the stent-assisted coiling of unruptured middle cerebral artery (MCA) aneurysms. This was a multicenter retrospective study. Patient demographics, aneurysm characteristics, procedural details, complications, and the results of clinical and imaging follow-up were analyzed. Four centers participated in the study. A total of 162 consecutive patients with 162 unruptured MCA aneurysms were included for the analysis. The mean aneurysm size was 7.6 mm (range 2 to 37 mm) and 97.5% were wide-necked. Immediate postprocedural angiograms showed Raymond-Roy class 1 in 118 (72.8%), class 2 in 23 (14.2%), and class 3 in 21 patients (13%). Periprocedural complications occurred in 14 patients (8.6%). There were no procedure-related deaths. Follow-up imaging at 12–18 months post-procedure showed Raymond–Roy class 1 in 132 (81.5%), class 2 in 17 (10.5%), and class 3 in 13 patients (8%). There were 3 cases of in-stent stenosis (1.9%). All 162 patients had good clinical outcome (mRS score 0–2) at 90 days post-procedure. Stent-assisted coiling of unruptured MCA aneurysms with the LVIS Jr. stent is safe and effective, with high immediate and long-term total occlusion rates.

Low-profile visible intraluminal support stent-assisted embolization therapy for intracranial dissecting aneurysms: A retrospective analysis of six cases

Endovascular Embolization (EVE) of aneurysms is a very effective and efficient treatment modality. Nevertheless, a few complications have been reported after EVE of aneurysms. Our study therefore evaluated the safety and efficacy of Low-profile Visible Intraluminal Support (LVIS) stentassisted EVE for intracranial Dissecting Aneurysms (DAs). We conducted a retrospective study to identify patients with DAs who were treated with LVIS stent from July 2015 to September 2018. The DAs were categoried into ruptured and unruptured. The arteries harbouring the aneurysm were identified in all cases. LVIS device stent assisted coil EVE treatment modality was utilized to treat all the patients. Surgical safety, immediate surgery outcome, recurrence rate and imaging follow-up results of all patients were analysed. The Glasgow Outcome Scale (GOS) score of all patients where assessed during discharge. Cerebral angiography of all patients were reevaluated on scheduled visits from three months up to one year after their operations. A total of Six DA patients were identified during our analysis. Four of the cases were ruptured DAs while two cases were unruptured. The DAs originated from the Internal Carotid Artery (ICA) in two cases, while in the remaining four cases, the DAs originated from vertebral artery (VA). Stents and coils were successfully implanted in all six patients. The DAs were embolized satisfactorily and the parent arteries were patent immediately after the operations. We obsereved 5 points GOS score in four cases and 4 points in two cases. No aneurysmal recurrece, no stent collapse or displacement was obsereved in all cases during follow-ups. Our study suggests that, LVIS stent-assisted EVE is simple, safe and effective in the treatment of DAs.

Coil Embolization of Wide-Neck Bifurcation Aneurysms via Shouldering and Framing: A Safe Alternative to Conventional Techniques

OBJECTIVE

Double stent-assisted coiling of wide-neck bifurcation aneurysms (WNBAs) can be technically challenging with high thromboembolic rates. Single stent-assisted coiling (SSAC) decreases procedural complexity and thromboembolic risk but increases risk of coil prolapse and recanalization. In this study, we present our institution's experience with SSAC of WNBA performed via a "shouldering" and "framing" with a single Atlas stent and a spherical 3-dimensional (3D) Stryker coil.

METHODS

A retrospective review of 35 patients who underwent SSAC of WNBA performed via a shouldering and framing with a single Atlas stent and a spherical 3D Stryker coil from 2018 to 2019. Data collection were performed on baseline demographics, clinical presentation, aneurysm characteristics, angiographic and functional outcomes, and perioperative and postoperative complications.

RESULTS

Of 35 patients, the mean age was 59.9 ± 11.6 years and 25/35 (71.4%) were women. The mean aneurysm diameter was 6.3 ± 3.4 mm, the mean neck size was 3.9 ± 1.3 mm, and the mean dome-to-neck ratio was 1.5 ± 0.6. Initial complete/near-complete occlusion was demonstrated in 30/35 (85.7%) patients. On angiographic follow-up at a mean of 6 months, 9/24 (37.5%) patients showed progressive thrombosis, 13/24 (54.2%) showed stable occlusion, and 2/24 (8.5) showed recanalization. Thromboembolic events occurred in 2/35 (5.7%) patients, intraoperative technical complications occurred in 2/35 (5.7%) patients, and access-site complications occurred in 2/35 (5.7%) patients. The were no cases of retreatment, rehemorrhage, or procedural-related permanent morbidity or mortality.

CONCLUSIONS

Coil embolization performed via shouldering with a single Atlas stent and framing with a spherical 3D Stryker coil is a feasible, safe, and effective neuroendovascular treatment for WNBAs.

Stent-assisted coiling of broad-necked intracranial aneurysms with a new braided microstent (Accero): procedural results and long-term follow-up

Intracranial stents have expanded endovascular therapy options for intracranial aneurysms. The braided Accero stent is available for clinical use since May 2015. To date, no clinical reports on the stent are available. Purpose of this study was the evaluation of the safety and efficacy of the Accero stent in stent-assisted coiling. All patients, in whom implantation of the stent was performed, were included. Primary endpoints were good clinical outcome (mRS ≤ 2) and aneurysm occlusion grades 1 and 2 (Raymond Roy Occlusion Classification). Secondary endpoints were procedural and device-related complications with permanent disability or death, complications in the course, and the recanalization rate. Between September 2015 and August 2018, thirty-four aneurysms were treated with stent-assisted coiling using the Accero. Sixteen aneurysms were untreated, four of these were ruptured. Mild neurological complications occurred in 2/34 (5.9%) treatments. Two stent occlusions occurred during follow-up. No patient had a poor procedure- or device-related outcome. After an average of 15 months of follow-up, 28/30 aneurysms were completely or near-completely occluded. The Accero stent proved to be safe and effective in the treatment of broad-based intracranial aneurysms. The complication rate and the rate of successful aneurysm occlusions are similar to those of other stents.

Cerebral aneurysms treated with low-profile visualized intraluminal support device (LVIS Jr) Y-stent constructs: Technical experience with a single microcatheter technique

BACKGROUND

The LVIS Jr device holds a number of advantages but poses unique technical challenges compared to such, especially, complex multistent constructs. We report our experience with the technical feasibility and early to mid-term outcomes of Y-stent-assisted coiling with the LVIS Jr using a simple, single microcatheter technique.

METHODS

Using a departmental database, we retrospectively reviewed a single surgeon's experience with Y-stent-assisted coiling with LVIS Jr over a three-year period. Eighteen aneurysms in 17 patients were treated over this period. We assessed the technical success of the procedures, the initial and follow-up radiographic success with the modified Raymond-Roy occlusion score and follow-up clinical outcome with the modified Rankin scale.

RESULTS

All stents were successfully deployed, and 17 of 18 aneurysms were successfully coiled at the initial treatment for a technical success rate of 94.4%. Of the 17 aneurysms with follow-up imaging, all were modified Raymond-Roy grade 1 or 2. One aneurysm required retreatment for coil compaction and a growing neck. There were two immediate postprocedure symptomatic strokes and one delayed stroke related to antiplatelet non-compliance. The two immediate symptomatic strokes recovered to neurological baseline with no residual deficits by the time of discharge. The long-term morbidity rate was 5.5%. The mortality rate was 0%. All patients had a modified Rankin Scale ≤ 2 at most recent follow-up.

CONCLUSION

Treatment with LVIS Jr Y-stent constructs via a single microcatheter technique is technically feasible with good radiographic and clinical outcomes.

Factors other than body weight predicting heparin loading to acquire optimal activated clotting time in endovascular neurointerventions

OBJECTIVES

The aim of this study was to investigate the relationship between the activated clotting time (ACT) and heparin loading based on body weight (BW), and factors other than BW that may contribute to the ACT after heparin loading to establish a more accurate regimen for achieving ACT targets during endovascular neurointerventions.

PATIENTS AND METHODS

Japanese patients who underwent endovascular coiling of unruptured intracranial aneurysms or carotid artery stenting in our institution between January 2014 and November 2017 were enrolled. The ACT was measured before (pre-ACT) and 3 min after heparinization (post-ACT). The correlation between ACT and heparin loading based on BW and factors that may contribute to the ACT after heparin loading were analyzed retrospectively.

RESULTS

A total of 199 cases (109 males, age: 66 ± 12 years) were analyzed. There were positive correlations between the heparin loading per kg of BW and post-ACT, post-ACT - pre-ACT (ΔACT) (Spearman's r = 0.2946, 0.2633, P: <0.0001, 0.0002, respectively). Heparin loading per kg of BW, gender, hematocrit (Ht), estimate glomerular filtration rate (eGFR) were significant confounding factors to ΔACT. The calculated predicted ΔACT based on these significant factors was found to be highly correlated with ΔACT compared with the heparin loading per kg of BW. (Spearman's r = 0.5820, P = <0.0001).

CONCLUSION

Initial BW-based heparin loading is a simple way in endovascular neurointerventions. ACT after heparin loading based on BW has individual differences greatly, it is possible to estimate more accurately the heparin loading for acquiring the optimal ACT considering not only BW but also gender, Ht and eGFR.

Double stent assisted coiling of intracranial bifurcation aneurysms in Y and X configurations with the Neuroform ATLAS stent: immediate and mid term angiographic and clinical follow-up

Purpose

Self-expandable stents have broadened the spectrum of endovascular treatment of intracranial aneurysms. However, procedures involving double stenting in Y/X configurations carry a relatively high risk of procedural complications. The Neuroform ATLAS, the evolution of Neuroform EZ, is a nitinol self-expanding hybrid/open cell stent which can be delivered through a low profile 0.017 inch catheter. We present our experience in the treatment of intracranial aneurysms with this stent in Y and X configurations.

Materials and methods

We prospectively maintained a database from consecutive patients who underwent double stent assisted coiling with the Neuroform ATLAS, from July 2015 to February 2019. Clinical and angiographic results were analyzed.

Results

55 patients harboring 55 bifurcation aneurysms were treated with double stenting: 52 ‘Y’ configurations, 3 ‘X’ configurations. Deployment was successful in all cases. Post-treatment control angiography showed complete occlusion in 33 cases (60%), neck remnant in 8 cases (14.5%), and incomplete occlusion in 14 cases (25.4%). The overall symptomatic periprocedural complication rate was 12.7%. 38 aneurysms underwent follow-up (69%, mean duration 16 months): 33 aneurysms (87%) were completely occluded, 3 aneurysms (8%) had a neck remnant, and 2 aneurysms (5%) were incompletely occluded.

Conclusion

The Neuroform ATLAS is an effective device for treatment of bifurcation aneurysms, allowing good conformability, a high level of navigability, and easy mesh crossing to perform Y/X stenting procedures. The rate of procedural complications remains non-negligible, and an indication for a double stenting procedure should be carefully discussed in a multidisciplinary meeting.

Comparison of endovascular treatment for middle cerebral artery aneurysm with a low-profile visualized intraluminal support stent or pipeline embolization device

The aim of the present study was to evaluate the safety and effectiveness of low-profile visualized intraluminal support (LVIS) stent and the pipeline embolization device (PED) for middle cerebral artery (MCA) aneurysm treatment. Data of patients with MCA aneurysms who received endovascular treatment with LVIS stent or PED added to the hospital's database between August 2016 and March 2018 were retrospectively collected, and the clinical results and angiographic outcomes were evaluated. A total of 43 patients were included in the study, of whom 23 received LVIS stents and 20 received PED. The rate of complete occlusion was similar in the two groups at 6 months post-treatment (90.9 vs. 88.9%; P=0.832). Peri-operative complications were more frequent in the PED group; however, the LVIS group had more ischemic symptoms during the long-term follow-up. A larger aneurysm size (P=0.032) was associated with recanalization in the two groups. In conclusion, the LVIS stent and PED had acceptable rates of complete occlusion and aneurysm size was an independent predictor for recanalization. LVIS is more effective during the peri-operative period, while PED appears to have higher long-term safety.

Endovascular Metal Devices for the Treatment of Cerebrovascular Diseases

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

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

BACKGROUND AND PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSION

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

Y-Stent-Assisted Coiling of Wide-Neck Bifurcation Intracranial Aneurysms: A Meta-Analysis

BACKGROUND

Y-stent-assisted coiling for wide-neck intracranial aneurysms required further investigation.

PURPOSE

Our aim was to analyze outcomes after Y-stent placement in wide-neck aneurysms.

DATA SOURCES

We performed a systematic search of 3 data bases for studies published from 2000 to 2018.

STUDY SELECTION

According to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, we included studies reporting Y-stent-assisted coiling of wide-neck aneurysms.

DATA ANALYSIS

Random-effects meta-analysis was used to pool the following: aneurysm occlusion rate, complications, and factors influencing the studied outcomes.

DATA SYNTHESIS

We included 27 studies and 750 aneurysms treated with Y-stent placement. The immediate complete/near-complete occlusion rate was 82.2% (352/468; 95% CI, 71.4%-93%; I² = 92%), whereas the long-term complete/near-complete occlusion rate was 95.4% (564/598; 95% CI, 93.7%-97%; I² = 0%) (mean radiologic follow-up of 14 months). The aneurysm recanalization rate was 3% (20/496; 95% CI, 1.5%-4.5%; I² = 0%), and half of the recanalized aneurysms required retreatment. The treatment-related complication rate was 8.9% (63/614; 95% CI, 5.8%-12.1%; I² = 44%). Morbidity and mortality after treatment were 2.4% (18/540; 95% CI, 1.2%-3.7%; I² = 0%) and 1.1% (5/668; 95% CI, 0.3%-1.9%; I² = 0%), respectively. Crossing Y-stent placement was associated with a slightly lower complication rate compared with the kissing configuration (56/572 = 8.4%; 95% CI, 5%-11%; I² = 46% versus 4/30 = 12.7%; 95% CI, 3%-24%; I² = 0%). Occlusion rates were quite comparable among Enterprise, Neuroform, and LVIS stents, whereas the Enterprise stent was associated with lower rates of complications (8/89 = 6.5%; 95% CI, 1.6%-11%; I² = 0%) compared with the others (20/131 = 14%; 95% CI, 5%-26%; I² = 69% and 9/64 = 11%; 95% CI, 3%-20%; I² = 18%).

LIMITATIONS

This was a small, retrospective series.

CONCLUSIONS

Y-stent-assisted coiling yields high rates of long-term angiographic occlusion, with a relatively low rate of treatment-related complications. Y-stent placement with a crossing configuration appears to be associated with better outcomes. Although Y-configuration can be obtained using many types of stents with comparable occlusion rates, the Enterprise stent is associated with lower complication rates.

Initial and Long-Term Outcomes of Complex Bifurcation Aneurysms Treated by Y-Stent-Assisted Coiling with Low-Profile Braided Stents

BACKGROUND AND PURPOSE

Coiling complex intracranial bifurcation aneurysms often necessitates the implantation of double stents in various configurations, such as Y-stent placement. Low-profile braided stents have been introduced recently to facilitate the endovascular treatment of wide-neck aneurysms. We aimed to investigate the feasibility, safety, efficacy, and durability of Y-stent-assisted coiling with double low-profile braided stents for the treatment of complex bifurcation aneurysms.

MATERIALS AND METHODS

A retrospective review was performed to identify patients who were treated using Y-stent-assisted coiling with low-profile braided stents. Technical success was assessed, as were initial and follow-up clinical and angiographic outcomes. Periprocedural and delayed complications were reviewed. Preprocedural and follow-up clinical statuses were assessed using the modified Rankin Scale.

RESULTS

Forty patients with 40 intracranial aneurysms were included in the study. Y-stent placement was successfully performed in all cases. Immediate postprocedural digital subtraction angiography images revealed total aneurysm occlusion in 72.5% of cases. The mean angiographic follow-up time was 24.8 months. The last follow-up angiograms showed complete occlusion in 85% of patients. During follow-up, only 1 patient showed an increase in the filling status of the aneurysm and that patient did not require retreatment. There was no mortality in this study. The overall procedure-related complication rate, including asymptomatic complications, was 17.5%. A permanent morbidity developed in 1 patient (2.5%).

CONCLUSIONS

The long-term angiographic and clinical outcomes of this retrospective study demonstrate that Y-stent-assisted coiling using low-profile braided stents is an effective, relatively safe, and durable endovascular treatment for wide-neck and complex bifurcation aneurysms.

Treatment of Intracranial Aneurysms with Self-Expandable Braided Stents: A Systematic Review and Meta-Analysis

BACKGROUND

The safety and efficacy of treatment with self-expandable braided stents (LEO and LVIS) required further investigation.

PURPOSE

Our aim was to analyze the outcomes after treatment with braided stents.

DATA SOURCES

A systematic search of 3 databases was performed for studies published from 2006 to 2017.

STUDY SELECTION

According to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, we included studies reporting patients treated with LEO or LVIS stents.

DATA ANALYSIS

Random-effects meta-analysis was used to pool the following: aneurysm occlusion rate, complications, and neurologic outcomes.

DATA SYNTHESIS

Thirty-five studies evaluating 1426 patients treated with braided stents were included in this meta-analysis. Successful stent delivery and complete aneurysm occlusion were 97% (1041/1095; 95% CI, 95%-98%) (I² = 44%) and 88.3% (1097/1256; 95% CI, 85%-91%) (I² = 72%), respectively. Overall, treatment-related complications were 7.4% (107/1317; 95% CI, 5%-9%) (I² = 44%). Ischemic/thromboembolic events (48/1324 = 2.4%; 95% CI, 1.5%-3.4%) (I² = 27%) and in-stent thrombosis (35/1324 = 1.5%; 95% CI, 0.6%-1.7%) (I² = 0%) were the most common complications. Treatment-related morbidity was 1.5% (30/1324; 95% CI, 0.9%-2%) and was comparable between the LEO and LVIS groups. Complication rates between the anterior (29/322 = 8.8%; 95% CI, 3.4%-12%) (I² = 41%) versus posterior circulation (10/84 = 10.5%; 95% CI, 4%-16%) (I² = 0%) and distal (30/303 = 8%; 95% CI, 4.5%-12%) (I² = 48%) versus proximal aneurysms (14/153 = 9%; 95% CI, 3%-13%) (I² = 46%) were comparable (P > .05).

LIMITATIONS

Limitations were selection and publication biases.

CONCLUSIONS

In this analysis, treatment with the LEO and LVIS stents was relatively safe and effective. The most common complications were periprocedural thromboembolisms and in-stent thrombosis. The rate of complications was comparable among anterior and posterior circulation aneurysms, as well as for proximal and distally located lesions.

Stent-assisted coil embolization of anterior communicating artery aneurysms using the LVIS Jr stent

BACKGROUND AND PURPOSE

This retrospective study evaluates the safety and mid-term and long-term effectiveness of stent-assisted coil embolization of anterior communicating artery (Acomm) aneurysms treated with the LVIS Jr stent.

MATERIALS AND METHODS

All patients treated with the LVIS Jr stent for Acomm aneurysms between June 2015 and March 2018 were included in the analysis. Details of the procedure's periprocedural adverse events, immediate aneurysm occlusion rates, and clinical and angiographic follow-up assessment were collected.

RESULTS

A total of 25 patients with 25 aneurysms were included. Eighteen aneurysms were found incidentally. Seven patients presented with seven ruptured aneurysms: Six were remotely ruptured and one acutely ruptured. Twenty-four patients were treated successfully and one technical failure is reported. The parent arteries measured 1.4 mm to 2.9 mm in diameter (mean, 2.3 mm). Intraprocedural thromboembolic complications occurred in two patients (8%) and an intraoperative aneurysm rupture in one patient (4%). Immediate complete aneurysm occlusion was noted in 18 out of 25 patients (72%). Clinical follow-up ranged from three months to 36 months (mean, 15.8 months) and the imaging follow-up ranged from two to 35 months (mean, 14.2 months). Complete aneurysm occlusion was achieved in 14 out of 20 patients (70%) at last angiographic follow-up. Of the two patients with in-stent thrombosis, one patient had an acutely ruptured aneurysm and the other patient was treated with an LVIS Jr stent in a Y configuration. Neurological morbidity and mortality rate were 0%.

CONCLUSIONS

Complex, wide-necked Acomm aneurysms can be effectively treated with stent-assisted embolization using LVIS Jr stents.

Y-configuration stenting for coiling of wide-neck bifurcation aneurysms using Low-profile Visualized Intraluminal Support Junior

Background

Little has been reported about the feasibility and durability of a Low-profile Visualized Intraluminal Support Junior (LVIS Jr) Y-stenting device for wide-neck bifurcation aneurysms.

Purpose

To evaluate the feasibility and durability of LVIS Jr Y-stenting for coiling of unruptured wide-neck bifurcation aneurysms.

Methods

We identified patients in whom LVIS Jr Y-stenting was attempted for unruptured wide-neck bifurcation aneurysms from a prospectively maintained registry of a referral hospital. Procedural success rate, treatment-related morbidity, and clinical and angiographic outcomes were retrospectively assessed.

Results

LVIS Jr Y-stenting was attempted for a total of 21 aneurysms in 21 patients (mean age 60±8.9 years; M:F=6:15): nine basilar artery, six anterior communicating artery, four middle cerebral artery, one internal carotid artery, and one vertebrobasilar fenestration aneurysms. The mean dome and neck size were 7.9±2.7 mm and 5.7±1.8 mm, respectively. All attempts were successful. Treatment-related morbidity occurred in one individual with a modified Rankin Scale (mRS) score of 2. Immediate postprocedural angiograms showed complete occlusion in 15 (71.4%) and neck remnant in 6 (28.6%) patients. All 21 patients had good outcomes (mRS score 0–2) for a mean of 12 months' follow-up (range 6–27 months); mRS score 0 in 20 patients and mRS score 2 in one patient, respectively. Follow-up imaging over a mean of 11 months (range 6–18 months) was available in 18 patients (85.7%). All aneurysms showed complete occlusion at follow-up.

Conclusions

LVIS Jr Y-stenting and coiling for wide-neck bifurcation aneurysms seems to be feasible with acceptable safety and to provide durable aneurysm occlusion for wide-neck bifurcation aneurysms.

China Intracranial Aneurysm Project (CIAP): protocol for a prospective cohort study of interventional treatment and craniotomy for unruptured aneurysms

INTRODUCTION

There are two approaches for the treatment of intracranial aneurysm (IA): interventional therapy and craniotomy, both of which have their advantages and disadvantages in terms of treatment efficacy. To avoid overtreatment of unruptured aneurysms (UIA), to save valuable medical resources and to reduce patient mortality and disability rate, it is vital that neurosurgeons select the most appropriate type of treatment to provide the best levels of care. In this study, we propose a refined, prospective, multicentre study for the Chinese population with strictly defined patient inclusion criteria, along with the selection of representative clinical participating centres.

METHODS AND ANALYSIS

This report describes a multicentre, prospective cohort study. As IA is extremely harmful if it ruptures, ethical issues need to be taken into account with regard to this study. Researchers are therefore not able to use randomised controlled trials. The study will be conducted by 12 clinical centres located in different regions of China. The trial recruitment programme begins in 2016 and is scheduled to be completed in 2020. We expect 1500 participants with UIA to be included. Clinical information relating to the participants will be recorded objectively. The primary endpoints are an evaluation of the safety and efficiency of interventional treatment and craniotomy for 6 months after surgery, with each participant completing at least 1 year of follow-up. The secondary endpoint is the evaluation of safety and efficacy of interventional therapy and craniotomy clipping when participants are treated for 12 months. We also address the success of treatment and the incidence of adverse events.

ETHICS AND DISSEMINATION

The research protocol and the informed consent form for participants in this study were approved by the Ethics Committee of Zhujiang Hospital of Southern Medical University (2017-SJWK-001). The results of this study are expected to be disseminated in peer-reviewed journals in 2021.

TRIAL REGISTRATION NUMBER

NCT03133598.

The Neuroform Atlas stent to assist coil embolization of intracranial aneurysms: a multicentre experience

Objective

To assess the clinical safety and efficacy of the Atlas microstent in stent-assisted coil embolization of wide-necked intracranial aneurysms.

Methods

Single-center observational study in 36 patients (24 female, 12 male, mean age 56 years) with 37 aneurysms for the endovascular treatment of wide-necked aneurysms. After giving informed consent, patients were included according to the following criteria: aneurysm dome-to-neck ratio <2 or neck diameter >4 mm, and a parent vessel diameter of ≤4.5 mm. Primary endpoint for clinical safety was absence of death, absence of major or minor stroke, and absence of transient ischemic attack. Primary endpoint for treatment efficacy was complete angiographic occlusion according to the Raymond-Roy occlusion classification (RROC) immediately after the procedure.

Results

In 36/37 (97%) cases, the primary endpoint of safety was reached, one patient had a transitory ischemic attack which completely resolved until discharge. In 31/37 (84%) cases, complete occlusion (RROC 1) was reached, and in 6/36 (17%), a residual neck remained (RROC 2). A sequential approach (first stent, then coiling through the same catheter) was used in 21 cases; the other 16 were treated with the jailing technique. Deployment was technically successful in all cases. Follow-up at a median of 6.1 months was available for 29/37 (78%) aneurysms and showed complete occlusion in 27/29 aneurysms (93%) and a neck remnant in 2 cases (7%).

Conclusion

Deployment of the Neuroform Atlas microstent is a safe and effective method for the treatment of intracranial wide-necked aneurysms.

LVIS Jr Device for Y-Stent-Assisted Coil Embolization of Wide-Neck Intracranial Aneurysms: A Multicenter Experience

Background and Purpose

Complex wide-neck intracranial aneurysms are challenging to treat. We report a multicenter experience using the LVIS Jr stent for "Y-stent"-assisted coiling embolization of wide-neck bifurcation aneurysms.

Methods

Seven centers provided retrospective data on patients who underwent Y-stenting. Technical complications, immediate posttreatment angiographic results, clinical outcomes, and imaging follow-up were assessed.

Results

Thirty patients/aneurysms were treated: 15 basilar tip, 8 middle cerebral artery, 4 anterior communicating artery, 1 pericallosal, and 2 posterior inferior cerebellar artery aneurysms. The mean aneurysm size was 11 mm and the mean dome-to-neck ratio was 1.3 mm. Twenty-four aneurysms were unruptured and treated electively, and 6 were acutely ruptured. Fifty-eight LVIS Jr stents were successfully deployed without any technical issue. One pro-cedural and transient in-stent thrombosis resolved with the intravenous infusion of a glycoprotein IIb/IIIa inhibitor. Five periprocedural complications (within 30 days) occurred: 2 periprocedural neurological complications (1 small temporal stroke that presented with transient aphasia and 1 posterior cerebral artery infarct) and 3 nonneurological periprocedural complications (2 retroperitoneal hematomas, and 1 patient developed a disseminated intravascular coagulopathy). One permanent complication (3.3%) directly related to Y-stenting was reported in the patient who suffered the posterior cerebral artery infarct. Immediate complete obliteration (Raymond-Roy Occlusion Classification [RROC] I-II) was achieved in 26 cases (89.6%). Twenty-four patients had clinical and imaging follow-up (mean 5.2 months). Complete angiographic occlusion (RROC I-II) was observed in 23 patients (96%). A good functional outcome with a modified Rankin Scale score ≤2 was achieved in 26 cases.

Conclusions

In this multicenter case series, Y-stent-assisted coiling of wide-neck aneurysms with the LVIS Jr device was feasible and relatively safe. Follow-up imaging demonstrated very low recanalization rates.

LVIS Jr. stent for treatment of intracranial aneurysms with parent vessel diameter of 2.5 mm or less

Background and purpose This retrospective study evaluates the safety, effectiveness, and long-term clinical and angiographic follow-up of intracranial aneurysms treated with the Low-Profile Visualized Intraluminal Support Junior (LVIS Jr.) stent and parent vessels of diameter equal to or less than 2.5 mm. Materials and methods We included all patients treated with the LVIS Jr. stent in aneurysms with small parent vessel diameter between March 2015 and July 2017. Periprocedural adverse events, immediate aneurysm occlusion rates, and clinical and angiographic follow-up are reported. Results A total of 35 patients with 35 aneurysms were included. Ten aneurysms were ruptured (28.6%) and 25 were unruptured (71.4%). The parent arteries measured 0.9 mm to 2.5 mm in diameter (mean, 2.2 mm). Intra-procedural thromboembolic complications occurred in four patients (11.4%) and there was an intraoperative aneurysm rupture in one patient (2.8%). Immediate complete aneurysm occlusion was noted in 21 out of 35 patients (60%). Clinical follow-up ranged between one and 25 months (mean, 10.5 months) and magnetic resonance angiography follow-up ranged between four and 24 months (mean, 10.4 months). Complete aneurysm occlusion was achieved in 21 out of 29 patients (72.4%) at last angiographic follow-up (mean, 9.4 months; range four to 23 months). In-stent stenosis occurred in one out of 29 patients (3.4%), who was asymptomatic. Of the four patients with in-stent thrombosis, three patients were treated with "Y configuration" (two patients with middle cerebral artery aneurysms and one patient with an anterior communicating artery aneurysm). Mortality rate was 0%. Neurological morbidity was 2.9%. Conclusions Stenting with the LVIS Jr. stent allowed us to treat complex intracranial aneurysms with parent vessel diameter of 2.5 mm or less with an acceptable safety profile.

LVIS Blue as a low porosity stent and coil adjuvant

Introduction

The LVIS Blue is an FDA-approved stent with 28% metallic coverage that is indicated for use in conjunction with coil embolization for the treatment of intracranial aneurysms. Given a porosity similar to approved flow diverters and higher than currently available intracranial stents, we sought to evaluate the effectiveness of this device for the treatment of intracranial aneurysms.

Methods

We performed an observational single-center study to evaluate initial occlusion and occlusion at 6-month follow-up for patients treated with the LVIS Blue in conjunction with coil embolization at our institution using the modified Raymond–Roy classification (mRRC), where mRRC 1 indicates complete embolization, mRRC 2 persistent opacification of the aneurysm neck, mRRC 3a filling of the aneurysm dome within coil interstices, and mRRC 3b filling of the aneurysm dome.

Results

Sixteen aneurysms were treated with the LVIS Blue device in conjunction with coil embolization with 6-month angiographic follow-up. Aneurysms were treated throughout the intracranial circulation: five proximal internal carotid artery (ICA) (ophthalmic or communicating segments), two superior cerebellar artery, two ICA terminus, two anterior communicating artery, two distal middle cerebral artery, one posterior inferior cerebellar artery, and two basilar tip aneurysms. Post-procedurally, there was one mRRC 1 closure, five mRRC 2 closures, and 10 mRRC 3a or 3b occlusion. At follow-up, all the mRRC 1 and mRRC 3a closures, 85% of the mRRC 3b closures and 75% of the mRRC 2 closures were stable or improved to an mRRC 1 or 2 at follow-up.

Conclusions

The LVIS Blue represents a safe option as a coil adjunct for endovascular embolization within both the proximal and distal anterior and posterior circulation.

Long-term follow-up of aneurysms treated electively with woven stent-assisted coiling

Background

Preliminary short-term results for stent-assisted coil embolization (SACE) using woven/braided stents have been promising. However, evidence supporting mid- to long-term efficacy and durability is lacking.

Objective

To report the long-term results for the durability of elective intracranial aneurysms treated with woven stents.

Materials and methods

Between May 2012 and May 2015, 98 consecutive patients with 103 aneurysms underwent elective woven SACE across three Australian neurovascular centres. All patients had immediate, 6- and 18-month clinical and radiological follow-up. Radiological assessment was performed with modified Raymond–Roy occlusion scores based on angiography results, while clinical assessment was based on the modified Rankin Scale.

Results

Six-month follow-up was available in 100 aneurysms, and an 18-month follow-up in 97 aneurysms. Total occlusion rates of 82% were achieved at inception, 82% at 6 months, and 90% at 18 months. Satisfactory occlusion with small neck remnants was present in 17% at inception, 16% at 6 months, and 9% at 18 months. Good neurological outcomes were achieved in 95% at 18 months. Intraprocedural thromboembolic events were recorded in 3% and delayed events in 1% (all in patients taking clopidogrel). Aneurysm recurrence occurred in one patient (1%). Technical complications occurred in 5%. The total complication rate was 10%.

Conclusions

Woven SACE is safe, efficacious, and durable at long-term 18-month follow-up, with very low recurrence and re-treatment rates. Preliminary results appear better than those for traditional laser-cut stents.

Safety and effectiveness of the Low Profile Visualized Intraluminal Support (LVIS and LVIS Jr) devices in the endovascular treatment of intracranial aneurysms: results of the TRAIL multicenter observational study

Background and purpose

To evaluate the safety and effectiveness of the low-profile braided intracranial stents called the Low Profile Visualized Intraluminal Support (LVIS) devices for stent-assisted coil embolization of wide-necked intracranial aneurysms.

Materials and methods

This was a prospective, multicenter, observational study of unruptured and ruptured intracranial aneurysms treated with the LVIS devices. Imaging and clinical data were independently analyzed respectively by CoreLab and Clinical Event Committee. Primary endpoints were clinical safety, effectiveness, and angiographic stability of the results at 6 and 18 months.

Results

Ten centers participated in the study; 102 patients were included and 90 patients (42.2% men, 57.8% women) were eventually analyzed, among which 27 (30.0%) had multiple aneurysms. Twenty-three (25.6%) were ruptured aneurysms, four of which (4.4%) were treated in the acute phase. One aneurysm was treated per patient; 92 LVIS and LVIS Jr devices were placed overall. The total aneurysm occlusion rate was 91.0% on immediate post-procedure angiograms, which remained unchanged at 6-month follow-up and was 92.4% at 18-month follow-up. One patient (1.1%) underwent retreatment between 6 and 18 months of follow-up. A modified Rankin score of 0 was documented for most cases immediately after the procedure (86.7%) and at 6-month (86.8%) and 18-month (83.3%) follow-up. The overall permanent morbidity rate at 18 months was 5.6% and the overall rate of events with sequelae related to the stent was 2.2%. The 18-month procedure-related mortality rate was 3.3%. No patient was deemed to require retreatment at 18-month follow-up.

Conclusion

The LVIS/LVIS Jr endovascular devices are safe and effective in the treatment of ruptured and unruptured intracranial aneurysms, with acceptable complication rates, very high immediate total occlusion rates, and stable angiographic results.

Utility of bulging technique for endovascular treatment of small and wide-necked aneurysms with a Low-profile Visualized Intraluminal Support (LVIS Jr.) device: A case report and review of the literature

Small and broad-necked aneurysms are generally very difficult to treat using endovascular therapy. The arrival of the low-profile stent (e.g., Low-profile Visualized Intraluminal Support; LVIS) has enabled reconstructive treatment for these aneurysms. In addition, the bulging technique using LVIS is an effective and attractive technique for performing stent-assisted coiling to preserve parent arteries and achieve neck coverage. We report here a patient with a small and wide-necked ruptured basilar artery (BA) top aneurysm, in whom successful treatment was achieved by stent-assisted coiling with LVIS Jr. using the bulging technique. A 74-year-old woman with moderate hypertension consulted for treatment of subarachnoid hemorrhage with a ruptured BA top aneurysm measuring 2.7 mm in height with a 4.3 mm neck. We initially tried emergency balloon-assisted coiling, but coiling proved difficult. We therefore performed stent-assisted coiling with LVIS Jr. using the bulging technique. The postoperative course was uneventful, with no aggravation of neurological symptoms, and the patient was discharged 14 days postoperatively. This treatment strategy with LVIS Jr. using the bulging technique may be very useful for patients with a ruptured aneurysm with a small and broad neck that would otherwise require treatment with intravascular devices or open surgery.

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

Objective

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

Materials and methods

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

Results

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

Conclusions

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

Long term follow-up of bifurcation aneurysms treated with braided stent assisted coiling and complex T- and Y- stent constructs

Background

Stent assisted coil embolization (SACE) of bifurcation aneurysms is challenging. Heterogeneous results have been achieved to date, but largely for laser cut stents. While braided stents offer multiple technical advantages, their long term efficacy has yet to be validated.

Objective

To report the first long term 18 month results for the durability of bifurcation aneurysms treated with braided stents.

Materials and methods

Over a 4 year period, 59 consecutive patients with 60 bifurcation aneurysms underwent elective braided SACE across three Australian neurovascular centers. 17 of these aneurysms underwent T- or Y-shaped stent constructs. All patients had immediate, 6 month and 18 month clinical and radiological follow-up. Radiological assessment was made on modified Raymond–Roy occlusion scores while clinical assessment was based on the modified Rankin Scale. Subgroup analysis of 17 aneurysms treated with multi-stent constructs was conducted.

Results

6 month follow-up data were available for 59 aneurysms and 18 month follow-up data for 58 aneurysms. Satisfactory aneurysm occlusion was achieved in 97% at inception and at 6 months, and 98% at 18 months. Good neurological outcomes were achieved in 95% at 18 months. Similar satisfactory results were achieved with the multi-stent construct cohort. Intraprocedural thromboembolic events were recorded in 5% and delayed events in 2%. Technical complications were found in 5%. All complication rate was 13%.

Conclusion

Braided SACE was safe, efficacious, and durable at the long term 18 month follow-up, including for multi-stent constructs. Preliminary results indicate favorable clinical and radiological outcomes compared with laser cut stents.

Flow Diversion with Low-Profile Braided Stents for the Treatment of Very Small or Uncoilable Intracranial Aneurysms at or Distal to the Circle of Willis

BACKGROUND AND PURPOSE

The endovascular treatment of aneurysms located at or distal to the circle of Willis and not amenable to coiling remains a challenge. We report our experience with flow-diversion treatment using low-profile braided stents as a stent monotherapy procedure for treating distally located very small or uncoilable aneurysms.

MATERIALS AND METHODS

We retrospectively reviewed our data bases to identify patients with aneurysms located at or distal to the circle of Willis who were treated with stent monotherapy using low-profile braided stents. The immediate and follow-up angiographic findings and clinical status of the patients were assessed.

RESULTS

Twenty aneurysms in 19 patients were included in the study. The mean size of the aneurysms was 4.7 ± 2.4 mm. Patients were treated via telescopic implantation of 2 stents for 11 aneurysms; single-stent placement was used for the remaining aneurysms. The technical success rate was 95%. We observed a technical complication in 1 case (5.3%) and a late ischemic event in another (5.3%). The final angiographies during a mean follow-up of 14.7 months showed complete aneurysm occlusion in 73.7%. The complete occlusion rate of the aneurysms treated with telescopic stent placement was 81.8%. The modified Rankin scale scores of all patients at the last follow-up were between 0 and 2.

CONCLUSIONS

Flow diversion with low-profile braided stents as a stent monotherapy procedure for very small or uncoilable intracranial aneurysms located at or beyond the circle of Willis is a promising, relatively safe, and durable endovascular procedure.

De novo vertebral artery dissecting aneurysm after internal trapping of the contralateral vertebral artery

We present the case of a de novo vertebral artery dissecting aneurysm (VADA) after endovascular trapping of a ruptured VADA on the contralateral side. The first ruptured VADA involved the posterior inferior cerebellar artery, which was successfully treated by endovascular internal trapping using a stent. A follow-up study at 3 months revealed a de novo VADA on the contralateral side. The second VADA was successfully embolized using coils while normal arterial flow in the vertebral artery was preserved using a stent. Increased hemodynamic stress may cause the development of a de novo VADA on the contralateral side.

Non-Contrast-Enhanced Silent Scan MR Angiography of Intracranial Anterior Circulation Aneurysms Treated with a Low-Profile Visualized Intraluminal Support Device

BACKGROUND AND PURPOSE

The Low-Profile Visualized Intraluminal Support Device comprises a small-cell nitinol structure and a single-wire braided stent that provides greater metal coverage than previously reported intracranial stents, as well as assumed strong susceptibility artifacts. This study aimed to assess the benefits of non-contrast-enhanced MRA by using a Silent Scan (Silent MRA) for intracranial anterior circulation aneurysms treated with Low-Profile Visualized Intraluminal Support Device stents.

MATERIALS AND METHODS

Thirty-one aneurysms treated with Low-Profile Visualized Intraluminal Support Device stents were assessed by using Silent MRA, 3D TOF-MRA, and x-ray DSA. The quality of MRA visualization of the reconstructed artery was graded on a 4-point scale from 1 (not visible) to 4 (excellent). Aneurysm occlusion status was evaluated by using a 2-grade scale (total occlusion/remnant [neck or aneurysm]). Weighted κ statistics were used to evaluate interobserver and intermodality agreement.

RESULTS

The mean scores ± SDs for Silent MRA and 3D TOF-MRA were 3.16 ± 0.79 and 1.48 ± 0.67 (P < .05), respectively, with substantial interobserver agreement (κ = 0.66). The aneurysm occlusion rates of the 2-grade scale (total occlusion/remnant [neck or aneurysm]) were 69%/31% for DSA, 65%/35% for Silent MRA, and 92%/8% for 3D TOF-MRA, respectively. The intermodality agreements were 0.88 and 0.30 for DSA/Silent MRA and DSA/3D TOF-MRA, respectively.

CONCLUSIONS

Silent MRA seems to be useful for visualizing intracranial anterior circulation aneurysms treated with Low-Profile Visualized Intraluminal Support Device stents.