LVIS Stent Versus Enterprise Stent for the Treatment of Unruptured Intracranial Aneurysms

The Enterprise stent…still useful after all these years

BACKGROUND

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

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSION

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

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

Treatment of broad-based intracranial aneurysms with the LVIS EVO stent: a retrospective observational study at two centers with short- and medium-term follow-up

The use of stents is well established in the treatment of broad-based intracranial aneurysms. The aim of this study is to report on safety, feasibility and midterm follow-up of the new LVIS EVO braided stent for the treatment of cerebral aneurysms. All consecutive patients with intracranial aneurysms who were treated with the LVIS EVO stent in two high volume neurovascular centers were retrospectively enrolled in this observational study. Clinical and technical complications, angiographic outcome and clinical short-term and midterm results were evaluated. The study included 112 patients with 118 aneurysms. 94 patients presented with incidental aneurysms, 13 patients with acute SAH and 2 patients with acute cranial nerve palsy. For 100 aneurysms a jailing technique was used, re-crossing of the stent was performed in 3 cases. For the residual 15 cases the stent was placed as a bail-out or as a second step. Immediate complete occlusion was observed in 85 aneurysms (72%). Midterm follow-up was available for 84 patients with 86 aneurysms (72.9%). One stent showed asymptomatic complete occlusion on follow-up imaging, in all other cases no in-stent stenosis was observed. The rate of complete occlusion was 79.1% at 6 months and 82.2% at 12-18 months. Midterm follow-up data of this retrospective observational cohort of two neurovascular centers corroborates the safety profile of the LVIS EVO device for treatment of ruptured and unruptured intracranial aneurysms.

Enterprise stents versus low-profile visualized intraluminal support stents for stent-assisted coiling of unruptured paraclinoid aneurysms

BACKGROUND

The microsurgical treatment of paraclinoid aneurysms can be challenging due to the anatomical structures that surround them.

OBJECTIVE

This study compared the clinical and angiographic outcomes of unruptured paraclinoid aneurysms treated with enterprise (EP) stents and low-profile visualized intraluminal support (LVIS) stents.

METHODS

A retrospective analysis of the clinical and radiological data from 133 patients with 139 unruptured paraclinoid aneurysms, who received an EP or an LVIS stent between January 2017 and June 2021 at Taizhou People's Hospital, was performed. Immediate postoperative and follow-up angiographic results were analyzed retrospectively using the Raymond-Roy occlusion classification (RROC). Any complications following the procedure and the patients' clinical outcomes were noted.

RESULTS

Enterprise stents were used for stent-assisted coiling in 64 patients with 68 aneurysms and LVIS stents were used in 69 patients with 71 aneurysms. Both groups exhibited an increase in the proportion of aneurysms meeting the criteria for RROC class I, but the LVIS group demonstrated a higher rate of aneurysms meeting the class I criteria compared with the EP group, both on immediate postoperative angiography (45.1% vs. 11.8%, p< 0.001) and on follow-up angiography (94.9% vs. 80.6%, p= 0.025). Procedure-related complications were experienced by 9.4% of patients in the EP group (one coil prolapse, two parent artery occlusions, and three thromboembolic events), and 8.7% of patients in the LVIS group (three stent-related thrombosis and three thromboembolic events). There were no statistically significant differences between the two groups in relation to perioperative complications (p= 0.746) or favorable clinical outcomes (p= 0.492).

CONCLUSION

A greater proportion of aneurysms in the LVIS group met the criteria for RROC class I compared with the EP group. There is no significant difference in procedural complications or clinical outcomes between EP and LVIS stents. Although no aneurysm recurrence was observed during the short follow-up period, continued monitoring is required.

Utility of low-profile visualized intraluminal support (LVIS™) stent for treatment of acutely ruptured bifurcation aneurysms: A single-center study

Objective

Stent-assisted coiling has been increasingly used in the treatment of intracranial aneurysms. However, its application in ruptured bifurcation aneurysms remains controversial and challenging. This study aimed to present the safety and feasibility of low-profile visualized intraluminal support (LVIS™, LVIS, and LVIS Jr.) stent for acutely ruptured bifurcation aneurysms.

Methods

A total of 41 patients with acutely ruptured intracranial aneurysms arising at the bifurcation were treated with LVIS™ stent-assisted coiling in our hospital between January 2017 and December 2021. The clinical data and angiographic results of the patients were analyzed.

Results

Among these patients, all stents were successfully implanted. According to the immediate angiographic results, 29 aneurysms (70.7%) were completely occluded. Intraoperative thrombosis and hemorrhage occurred in two and one cases, respectively. No post-operative thrombosis or rebleeding events were observed. The clinical follow-up of all patients revealed that 38 (92.7%) cases had favorable outcomes (modified Rankin scale: 0-2). The angiographic results available for the 36 patients during the follow-up period revealed complete occlusion was achieved in 30 patients (83.3%) and residual neck in six patients.

Conclusion

The LVIS™ stent-assistant coiling is a safe and feasible option for acutely ruptured bifurcation aneurysms. Further studies with a prospective design, a larger sample size, and long-term follow-up are needed to validate these findings.

Stent-assisted coiling vs. coiling alone of ruptured tiny intracranial aneurysms: A contemporary cohort study in a high-volume center

Objective

This study aims to compare the safety and efficacy of stent-assisted coiling (SAC) with those of coiling alone (CA) for the treatment of ruptured tiny intracranial aneurysms.

Methods

We enrolled 245 patients with ruptured tiny intracranial aneurysms treated with coil embolization. Patients were grouped into SAC and CA groups. Baseline characteristics, periprocedural complications, clinical outcomes, and angiographic results were compared between the two groups. In addition, a subgroup analysis was conducted in the SAC group, and patients were regrouped into low-profile visualized intraluminal support (LVIS) and laser-cut groups to compare the perioperative procedure-related complications and clinical and angiographic follow-up outcomes.

Results

All baseline characteristics were equivalent between the two groups except for aneurysm size and dome-to-neck aspect ratio. The rates of overall procedure-related complications, intraprocedural rupture, postoperative early rebleeding, intraprocedural thrombosis, postprocedural thrombosis, and procedure-related mortality were comparable between the two groups (P = 0.105, 0.145, 0.308, 1.000, 1.000, 0.160, respectively). Nevertheless, the rate of hemorrhagic complication in the SAC group was significantly higher (P = 0.023). The angiographic follow-up outcomes showed that the SAC group had a higher complete occlusion rate and lower recurrence rate (88.2 vs. 67.1%, 5.4 vs. 15.2%, P = 0.001). The clinical outcomes at discharge and follow-up between the two groups demonstrated no significant differences (P = 0.192 and P = 0.085, respectively). For subgroup analysis, LVIS stents were associated with a significantly higher rate of complete occlusion (P = 0.014) and a lower rate of intraprocedural rupture (p = 0.021). Moreover, multivariate analysis showed that there were no predictors for the overall, hemorrhagic, and ischemic procedure-related complications, while Raymond class was an independent predictor of retreatment (OR = 3.508, 95% CI 1.168-11.603; P = 0.029).

Conclusion

Stent-assisted coiling may increase the incidence of hemorrhagic events with favorable angiographic results and comparable clinical outcomes compared with stand-alone coiling. Nevertheless, LVIS stent could improve the safety compared with lazer-cut stent. Simultaneously, considering the better long-term effect, LVIS stent-assisted coiling may be a preferable choice for ruptured tiny intracranial aneurysms.

Effect of the Shelving Technique on the Outcome of Embolization in Intracranial Bifurcation Aneurysms

BACKGROUND AND PURPOSE

Stent bulging technique has been introduced as a technique that improves the outcome of aneurysm coiling. Our aim was to evaluate the utility of this technique, which involves the intentional herniation of stents into the bifurcation aneurysms during coiling.

MATERIALS AND METHODS

Unruptured bifurcation aneurysms treated by stent-assisted coiling using a single type of low-profile braided (LEO Baby) stent between November 2012 and October 2018 were retrospectively evaluated. The clinical (age and sex) and morphologic characteristics (aneurysm size, neck size, proximal/distal diameters of the stented artery, incorporation of the origins of the side branches to the aneurysm neck, and bifurcation angle) and response to antiplatelet therapy were evaluated.

RESULTS

Sixty-one patients (29 men, 47.5%; mean age, 55.95 [SD, 12.33] years) with 66 aneurysms were included. There were 36 aneurysms in group A (treated with the stent bulging technique) and 30 aneurysms in group B (treated by classic stent-assisted coiling). There was no significant difference in the patient and aneurysm characteristics in the groups except for the larger size and wider neck of the aneurysms in group A (P = .02 and P = .04, respectively). At the mean follow-up of 27.30 (SD, 17.45) months, there was no significant difference in the complication rate, the occlusion status, and the early and long-term occlusion rates between the groups. The stent bulging technique did not predict total occlusion (Raymond-Roy I) at the final imaging follow-up.

CONCLUSIONS

The stent bulging technique enables the coiling of larger, wide-neck aneurysms; however, we did not observe an added flow-diversion effect with the stent bulging technique compared with conventional stent-assisted coiling. We, therefore, suggest that bifurcation aneurysms should be coiled as densely and as safely as possible using this technique.

Braided stents assisted coiling for endovascular management of posterior cerebral artery aneurysms: a preliminary mid-term experience

PURPOSE

Posterior cerebral artery (PCA) aneurysms are rare. This study is to evaluate the preliminary experience of braided stents applied in PCA aneurysms treatment.

METHODS

Angiographic and clinical data of 28 PCA patients treated with braided stents from July 2016 and September 2020 were retrospectively analyzed.

RESULTS

A total of 28 PCA aneurysms were enrolled. 22 (78.6%) aneurysms were dissecting aneurysms, while 6 (21.4%) aneurysms were saccular aneurysms. Thirty-five braided stents were implanted with dual stents implanted in 7 cases. Immediate angiographic results show that Raymond class I was obtained in 13 patients (46.4%), Raymond class II was obtained in 4 patients (14.3%), and Raymond class III was obtained in 11 patients (39.3%). Perioperative hemorrhagic events occurred in 1 patient (3.6%). Twenty-four patients (85.7%) received angiographic follow-up, and the mean follow-up time was 11.2 ± 4.9 months. Two patients (8.3%) were confirmed with IA neck recurrence, and 3 patients (12.5%) were confirmed asymptomatic parent artery occlusion (PAO). The other 19 patients were confirmed promoted occlusion with 18 Raymond class I (75%) and 1 Raymond class II (4.2%). Twenty-seven patients (96.4%) received clinical follow-up, and the mean follow-up time was 32.2 ± 13.5 months. One patient (3.7%) confirmed the death event 2 weeks after discharge. The other 27 patients (96.3%) got favorable clinical outcomes with an mRS score of 0-2.

CONCLUSIONS

Braided stent-assisted coiling with a high occlusion rate and relatively low complication rate provides an alternative strategy in treating PCA aneurysms. Long-term outcomes need further randomized study with larger case numbers.

Overlapping stents-assisted coiling for vertebral artery dissecting aneurysm: LVIS stent within Neuroform EZ stent

Objective

Methods

Results

Conclusion

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.

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.

Safety and efficacy of stent-assisted coiling for acutely ruptured wide-necked intracranial aneurysms: comparison of LVIS stents with laser-cut stents

Background

To compare the safety and efficacy of LVIS stent-assisted coiling with those of laser-cut stent-assisted coiling for the treatment of acutely ruptured wide-necked intracranial aneurysms.

Methods

Patients with acutely ruptured wide-necked intracranial aneurysms treated with LVIS stent-assisted coiling (LVIS stent group) and laser-cut stent-assisted coiling (laser-cut stent group) were retrospectively reviewed from January 2014 to December 2017. Propensity score matching was used to adjust for potential differences in age, sex, aneurysm location, aneurysm size, neck width, Hunt-Hess grade, and modified Fisher grade. Perioperative procedure-related complications and clinical and angiographic follow-up outcomes were compared. Univariate and multivariate analyses were performed to determine the associations between procedure-related complications and potential risk factors.

Results

A total of 142 patients who underwent LVIS stent-assisted coiling and 93 patients who underwent laser-cut stent-assisted coiling were enrolled after 1:2 propensity score matching. The angiographic follow-up outcomes showed that the LVIS stent group had a slightly higher complete occlusion rate and lower recurrence rate than the laser-cut stent group (92.7% vs 80.6%; 3.7% vs 9.7%, P = 0.078). The clinical outcomes at discharge and follow-up between the two groups demonstrated no significant differences (P = 0.495 and P = 0.875, respectively). The rates of intraprocedural thrombosis, postprocedural thrombosis, postoperative early rebleeding, and procedure-related death were 0.7% (1/142), 1.4% (2/142), 2.8% (4/142), and 2.1% (3/142) in the LVIS stent group, respectively, and 4.3% (4/93), 2.2% (2/93), 1.1% (1/93), and 3.2% (3/93) in the laser-cut stent group, respectively (P = 0.082, 0.649, 0.651, and 0.683). Nevertheless, the rates of overall procedure-related complications and intraprocedural rupture in the LVIS stent group were significantly lower than those in the laser-cut stent group (5.6% vs 14.0%, P = 0.028; 0.7% vs 6.5%, P = 0.016). Multivariate analysis showed that laser-cut stent-assisted coiling was an independent predictor for overall procedure-related complications (OR = 2.727, P = 0.037); a history of diabetes (OR = 7.275, P = 0.027) and other cerebrovascular diseases (OR = 8.083, P = 0.022) were independent predictors for ischemic complications, whereas none of the factors were predictors for hemorrhagic complications.

Conclusions

Compared with laser-cut stent-assisted coiling, LVIS stent-assisted coiling for the treatment of acutely ruptured wide-necked intracranial aneurysms could reduce the rates of overall procedure-related complications and intraprocedural rupture.

Endovascular treatment with the Enterprise stent versus the Neuroform or Low-Profile Visualized Intraluminal Support stent for unruptured aneurysms

Aim: To compare outcomes among patients undergoing endovascular treatment for unruptured intracranial aneurysm (UIA) with the Enterprise stent versus the Neuroform or Low-Profile Visualized Intraluminal Support (LVIS) stent. Patients & methods: Patients undergoing endovascular procedure for UIA were classified into Enterprise stent and Neuroform or LVIS stent group. Groups were propensity-score matched and generalized estimating equations were used for outcomes assessment. Results: There were no significant between-group differences in length of stay or mortality. The Enterprise group had significantly lower odds of UIA-related inpatient readmissions versus the Neuroform/LVIS group (odds ratio: 0.62; 95% CI: 0.42-0.91). Conclusion: Enterprise stent use was associated with significantly lower readmissions versus competitor stent, with no difference in other study outcomes.

Endovascular Treatment of Ruptured Middle Cerebral Artery Aneurysms With a Low-Profile Visualized Intraluminal Support Device

Objective: Stenting in ruptured middle cerebral artery (MCA) aneurysms was reported with a high perioperative complication rate. However, the treatment devices and physician's experience have continued to evolve. We performed this retrospective study to evaluate the safety and efficacy of LVIS stent-assisted coiling for ruptured MCA aneurysms.

Methods: Patients with acutely ruptured MCA aneurysms treated between November 2014 and October 2019 were retrospectively reviewed. Clinical and angiographic data of those treated with LVIS stents were collected from a prospectively maintained database.

Results: A total of 40 patients with 40 ruptured MCA aneurysms were enrolled, which comprised 26.3% (40/152) of all the ruptured MCA aneurysms at the same time. All stents were successfully deployed except for one (2.5%), which had a poor stent opening. Ischemic procedure-related complications were encountered in three patients (7.5%). One patient died of complications related to high-grade SAH on admission. Follow-up (mean 15.9 months) angiography was performed for 36 patients, which showed 33 (91.7%) aneurysms were completely occluded, 1 (2.8%) was improved, 1 (2.8%) was stable, and 1 (2.8%) was recanalized. Clinical follow-up (mean 29.6 months) was available for all survived patients, which showed 38 (95.0%) patients had favorable neurologic outcomes (mRS score 0–2), and 2 (5.0%) patients had poor neurologic outcomes.

Conclusion: The use of LVIS stents is feasible, safe, and effective with glycoprotein IIb/IIIa inhibitor for the treatment of ruptured MCA aneurysms in the acute setting. Prospective, multicenter studies with larger sample sizes are still required to further evaluate the safety and long-term efficacy.

Two Patients with Large Aneurysms in Whom Coil Embolization with Overlapping LVIS Stents Was Performed

Objective

We report two patients with unruptured large aneurysms treated by overlapping stent-assisted coil embolization using low-profile visualized intraluminal support (LVIS) stents.

Case Presentation

Case 1: An 80-year-old woman presented with abducens nerve palsy due to an internal carotid artery aneurysm. Case 2: A 75-year-old man presented with a partially thrombosed fusiform aneurysm in the vertebral artery (VA). Both patients were treated by overlapping LVIS stent-assisted coil embolization (overlapping LSACE). Digital subtraction angiography (DSA) a few months after embolization demonstrated complete occlusion of the aneurysm, although immediate angiography revealed dome filling.

Conclusion

Overlapping LSACE may be an effective treatment method for aneurysms that are difficult to treat by standard SACE and result in better flow-diverting effects.

The Enterprise2 Stent for Endovascular Treatment of Intracranial Aneurysms: Short-Term Results From a Single Center Experience

Background: Self-expanding devices, such as the Enterprise VRD (EP-VRD) have widely used for stent-assisted coiling treatment in wided-necked aneuryms while some thromboembolic complications were reported due to its incomplete stent apposition (ISA). We report our experiences on the novel Enterprise2 (EP-VRD2) stent in vivo in the treatment of intracranial and cranial cervical junction aneurysms.

Methods: Twenty-five consecutive patients with intracranial or cranial cervical junction aneurysms were treated with EP-VRD2 stents retrospectively collected in our institution. We use the ‘jailing' technique in all cases and deployed the stent by using pushing over the outer curve technique. The 3- or 6-monthS follow-up was done regularly by DSA.

Results: Twenty-five EP-VRD2 stents were implanted to treat 21 aneurysms at the siphon segment of internal carotid artery (ICA), one at the petrous segment, two at the cervical segment, one at the verteral artery with five accompanied with stenosis. Two patients had kinking during the procedure and were solved by microwire or microcatheter massaging. Four patients with a larger arc angle and a smaller radius of the parent vessel was detected ISA. No patient underwent the ischemic event after the operation. Twenty-three of 25 patients were evaluated after 3- or 6-months by DSA, 22 showed complete occlusion (RROC1), one slight re-stenosis in the follow-up within those five patients with stenosis. A length of 23 mm seemed associated with ISA (p < 0.01).

Conclusion: The EP-VRD2 performed well in our small patient series; however, ISA could still occur with a sharp angle of the parent vessel.

In vivo comparison of braided (Accero) and laser-cut intracranial stents (Acclino, Credo): evaluation of vessel responses at subacute and mid-term follow-up in a rabbit model

This study aimed to investigate in vivo two stent technologies, with particular emphasis on thrombogenicity and inflammatory vessel remodeling processes. The micro-stents tested in this study were developed for intracranial aneurysm treatment. In our study twelve, New Zealand white rabbits were divided into two groups: 18 laser-cut stents (LCS) and 18 braided stents (BS) were impanated without admiration of antiplatelet medication. Three stents were implanted into each animal in the common carotid artery, subclavian artery, and abdominal aorta. Digital subtraction angiography was performed before and after stent implantation and at follow-up for the visualization of occurring In-stent thromboembolism or stenosis. The Stents were explanted for histopathological examination at two different timepoints, after 3 and 28 days. Angiographically neither in-stent thrombosis nor stenosis for both groups was seen. There was a progressive increase in the vessel diameter, which was more pronounced for BS than for LCS. We detected a higher number of thrombi adherent to the foreign material on day 3 for BS. On day 3, the neointima was absent, whereas the complete formation observed was on day 28. There was no significant difference between both groups regarding the thickness of the neointima. The in vivo model of our study enabled the evaluation of blood and vessel reactions for two different stent technologies. Differences in vessel dimension and tissue around the stents were observed on day 28. Histological analysis on day 3 enabled the assessment of thrombotic reactions, representing an important complementary result in long-term studies.

Hemodynamic differences by increasing low profile visualized intraluminal support (LVIS) stent local compaction across intracranial aneurysm orifice

BACKGROUND

The Low-profile Visualized Intraluminal Support device (LVIS) has been successfully used to treat cerebral aneurysm, and the push-pull technique has been used clinically to compact the stent across aneurysm orifice. Our aim was to exhibit the hemodynamic effect of the compacted LVIS stent.

METHODS

Two patient-specific aneurysm models were constructed from three-dimensional angiographic images. The uniform LVIS stent, compacted LVIS and Pipeline Embolization Device (PED) with or without coil embolization were virtually deployed into aneurysm models to perform hemodynamic analysis. Intra-aneurysmal flow parameters were calculated to assess hemodynamic differences among different models.

RESULTS

The compacted LVIS had the highest metal coverage across the aneurysm orifice (case 1, 46.37%; case 2, 67.01%). However, the PED achieved the highest pore density (case 1, 19.56 pores/mm²; case 2, 18.07 pores/mm²). The compacted LVIS produced a much higher intra-aneurysmal flow reduction than the uniform LVIS. The PED showed a higher intra-aneurysmal flow reduction than the compacted LVIS in case 1, but the results were comparable in case 2. After stent placement, the intra-aneurysmal flow was further reduced as subsequent coil embolization. The compacted LVIS stent with coils produced a similar reduction in intra-aneurysmal flow to that of the PED.

CONCLUSIONS

The combined characteristics of stent metal coverage and pore density should be considered when assessing the flow diversion effects of stents. More intra-aneurysmal flow reductions could be introduced by compacted LVIS stent than the uniform one. Compared with PED, compacted LVIS stent may exhibit a flow-diverting effect comparable to that of the PED.

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.

Recent advances in stent-assisted coiling of cerebral aneurysms

INTRODUCTION

Stent-assisted coiling (SAC) of intracranial aneurysms paved the way for endovascular coiling of wide-neck and bifurcation aneurysms, improving rates of aneurysm obliteration and recurrence. In this review, we provide a comprehensive review of the most recent advances related to stent-assisted coiling of intracranial aneurysm.

AREAS COVERED

The authors have made an attempt to cover the inception, applications, and limitations of SAC of intracranial aneurysms. Special focus is given to 1) the current and recently introduced SAC techniques, 2) most recent advances in device technology, and 3) outcome data for the discussed techniques and devices. The authors also discuss the potential future direction of SAC.

EXPERT OPINION

technical refinements in the field of SAC should continue to focus on device development and addressing the limitations of SAC, namely aneurysm recurrence and need of antiplatelet agents. Although the recurrence rate of SAC has not been shown to be inferior to flow diverters, the use of intrasaccular and intravascular flow diverters are likely to expand in the future at the expense of SAC.

Comparison of Low-Profiled Visualized Intraluminal Support Stent-Assisted Coiling and Coiling Only for Acutely Ruptured Intracranial Aneurysms: Safety and Efficacy Based on a Propensity Score-Matched Cohort Study

BACKGROUND

Low-profiled visualized intraluminal support (LVIS) is suggested as a promising stent for complex intracranial aneurysms. However, the safety and efficacy of LVIS-assisted coiling of acutely ruptured wide-necked intracranial aneurysms have not been well reported.

OBJECTIVE

To evaluate the safety and efficacy of LVIS-assisted coiling of acutely ruptured wide-necked intracranial aneurysms compared with contemporary coiling-only strategy via propensity score matching in a high-volume center.

METHODS

A retrospective review of patients with acutely ruptured intracranial aneurysms who underwent LVIS stent placement or coiling only from November 2013 to October 2017 was performed. Perioperative procedure-related complications and clinical and angiographic follow-up outcomes were compared.

RESULTS

All baseline characteristics were equivalent between the 2 groups except for neck size. The immediate angiographic results, procedure-related complications, procedure-related mortality, and clinical outcomes between the 2 groups demonstrated no significant differences (P = .087, P = .207, P = .685, and P = .865, respectively). The angiographic follow-up outcomes of the LVIS-assisted coiling group showed a significantly higher complete occlusion rate and lower recurrence rate compared with the coiling-only group (92.3% vs 59.9%, 4.8% vs 26.1%, P &lt; .001). Multivariable analysis showed no significant predictors for the overall perioperative procedure-related complications, hemorrhagic complications, and ischemic complications.

CONCLUSION

The LVIS stent is a safe and effective device for stent-assisted coiling of acutely ruptured wide-necked intracranial aneurysms, with comparable procedure-related complication rates, higher complete occlusion rates, and lower recurrence rates at follow-up compared with coiling only.

Additional Embolization for Intra-aneurysmal Blood Flow Resumption after Stent-assisted Embolization of Cerebral Aneurysms

Objective

Stent-assisted aneurysmal embolization (SAAE) is an effective treatment for aneurysms with a low risk of recurrence. In rare cases, retreatment is necessary due to recanalization of blood flow into the aneurysm. However, only a few studies have reported on retreatment. We examined the efficacy and complications of stent-assisted aneurysm embolization for large or wide-neck aneurysms at our hospital.

Methods

Between July 2010 and June 2018, 293 patients underwent stent-assisted aneurysm embolization at our hospital. Among them, 12 (2 women, 10 men, mean age: 62 years) needed retreatment. We evaluated the initial treatment of these 12 patients, and the methods and results of their retreatment.

Results

Six of the 12 retreated patients were treated using the simple technique. It was possible to treat nine patients (75%) without placing new stents, but three needed additional stents. We were able to guide the microcatheter into the aneurysm using the trans-cell technique even with two overlapping stents. We achieved complete embolism in seven patients (58%), and remnants were observed in the neck in five (42%) patients. No complications were associated with our surgery. We were able to perform follow-up for 10 patients and there was no recurrence.

Conclusion

Embolization should be considered in recurrent cases after the initial stent-assisted coil embolization. We achieved good results and reduced the recurrence rate by selecting the appropriate treatment in each case.

Acute hemorrhagic cerebral artery dissection: Characteristics and endovascular treatment

OBJECTIVE

Acute hemorrhagic cerebral artery dissection may show a subtle stenosis and bulge on an angiogram, for which diagnosis and treatment are difficult. This report describes seven cases of acute hemorrhagic cerebral artery dissection treated by endovascular techniques.

PATIENTS AND METHODS

From January 2018 to April 2019, seven patients (22-76 years old) were diagnosed with subarachnoid hemorrhage caused by cerebral artery dissection. Six patients were treated by low-profile visualized intraluminal support stent-assisted coiling and there was a sacrifice of the posterior cerebral artery in one patient. Cerebral angiography results were obtained immediately after intervention and at follow-up. Clinical outcome was evaluated by a modified Rankin Scale score.

RESULTS

Four dissections were angiographic changes of subtle stenosis and small bulges; three were apparent angiographic changes of stenosis or fusiform morphologies. All seven aneurysms were completely obliterated, a low-profile visualized intraluminal support stent was used in six patients and coil occlusion of the parent artery in one patient. Complications occurred in two cases of proximal posterior cerebral artery dissection. One bleeding complication was observed intra-procedure and one ischemic complication was observed after stent-assisted coiling. The angiographic and clinical follow-up was obtained at 3-8 months in five patients. Good recovery was achieved for six patients (modified Rankin Score 0); one patient who presented Weber syndrome caused by ischemic complication had a modified Rankin Score of two at 8 months follow-up.

CONCLUSION

Hemorrhagic cerebral artery dissection may show subtle stenosis, small bulges or fusiform morphologies on angiograms. Treatment of proximal posterior cerebral artery dissection is challenging. Endovascular reconstruction with a low-profile visualized intraluminal support stent was effective depending on the angiographic morphology.

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

Introduction

One of the popular treatment strategies for complex cerebral aneurysms with wide necks or low dome-to-neck ratios is stent-assisted coiling. The most widely used intracranial stents for stent-assisted coiling are Neuroform (NF) and Enterprise (EP) stents. The purposes of this study are to review the recent literature of the past 5 years to compare outcomes between the EP and NF stent-assist coiling systems so as to comment on the safety, efficacy, complications, and recurrence rate of stent-assisted coiling in general.

Methods

PubMed was used to search for all published literature of NF or EP stent-assisted coiling of unruptured cerebral aneurysms from January 2014 to August 2019 with the search terms of "Enterprise stent-assisted coiling," "Neuroform stent," and "Neuroform vs. Enterprise stent."

Results

Twenty two publications met the inclusion criteria which encompass 1764 patients and 1873 aneurysms. Out of these 1873 aneurysms, 1007 aneurysms were treated with EP stent and 866 aneurysms were treated with NF stent. The overall outcome was low rates of thromboembolic complications (4.37%) and intracranial hemorrhage (1.13%), low permanent morbidity (1.70%) and mortality (0.40%), and lower rate of recanalization (11%). Data analysis shows an overall higher rate of complication and recurrence of aneurysm and lower overall rate of aneurysmal occlusion in the patients where EP stent was used in comparison to NF stent. However, this difference was not statistically significant.

Conclusions

The review of two stent-assisted coiling devices using EP and NF stents including 1873 aneurysms in 1764 patients revealed that overall, it is safe and effective with comparable outcomes.

Alpha Stent for Coiling of Unruptured, Wide-Necked, Distal Internal Carotid Artery Aneurysms: Safety and Effectiveness at 6 Months

OBJECTIVE

The Alpha stent (CGBio), a new intracranial stent featuring a re-sheathable mesh design with improved wall apposition at the curved segment, was clinically evaluated. We report the 6-month follow-up results from a prospective, single-center study in which the stent was used for coiling of wide-necked distal internal carotid artery (ICA) aneurysms.

MATERIALS AND METHODS

Between April 2016 and 2018, 50 patients (mean age, 56.5 years, 45 females [90%]) with 54 unruptured distal ICA aneurysms (average diameter: 5.6 ± 1.7 mm) were enrolled. The primary endpoint for effectiveness was successful coil embolization with the Alpha stent, and subsequent complete or near-complete occlusion at the 6-month magnetic resonance angiography assessment. The primary safety endpoint was the absence of serious adverse events (SAEs) up to 6 months from the procedure.

RESULTS

The primary effectiveness endpoint was observed in 94.4% (51/54) aneurysms. In one patient with technical failure, the stent could not be deployed because of parent artery tortuosity; therefore, a different type of stent was used. Of the 53 aneurysms treated with the Alpha stent, complete occlusion was achieved in 64.1% (34/53) cases, and near-complete occlusion was achieved in 32.0% (17/53) cases by the 6-month follow-up. Two cases (3.7%) required retreatment because of major recurrence. In 4% (2/50) patients, SAEs, i.e., retinal artery thromboembolism and corona radiata lacunar infarction, were reported after the procedure.

CONCLUSION

For endovascular treatment of unruptured, wide-necked, distal ICA aneurysms, coil embolization using the newly developed Alpha stent showed excellent procedural and mid-term clinical follow-up results in terms of effectiveness and safety.

Clinical Safety and Effectiveness of Stent-Assisted Coil Embolization with Neuroform Atlas Stent in Intracranial Aneurysm

Objective

Stent-assisted coil embolization (SAC) is commonly used for treating wide-neck intracranial aneurysms. In this study, we aimed to assess the clinical safety and efficacy of the NeuroForm Atlas Stent during SAC of intracranial aneurysms.

Methods

We retrospectively analyzed data from patients with ruptured and unruptured cerebral aneurysms, who underwent SAC using the NeuroForm Atlas between February 2018 and July 2018. Favorable clinical outcomes and degree of aneurysm occlusion were defined as a modified Rankin scale score of ≤2 and a Raymond-Roy occlusion classification (RROC) class I/II during the immediate postoperative period and at the 6-month follow-up, respectively.

Results

Thirty-one consecutive patients with 33 cases, including 11 ruptured and 22 unruptured cases were treated via NeuroForm Atlas SAC. Among the 22 unruptured cases with 24 unruptured aneurysms had favorable clinical outcome. Complete occlusion (RROC I) was achieved in 16 aneurysms (66.7%), while neck remnants (RROC II) were observed in six aneurysms (25%). Among the 11 patients with ruptured aneurysms, two died due to re-bleeding and diabetic ketoacidosis. In ruptured cases, RROC I was observed in eight (72.7%) and RROC II was observed in three cases (27.3%). At the 6-month follow-up, no clinical events were observed in the 22 unruptured cases. In the ruptured nine cases, five patients recovered without neurologic deficits, while four experienced unfavorable outcomes at 6 months. Of the 29 aneurysms examined via angiography at the 6-month follow-up, 19 (65.5%) were RROC I, eight (27.6%) were RROC II and two (6.9%) were RROC III. There were no procedure-related hemorrhagic complications.

Conclusion

In this study, we found that stent-assisted coil embolization with NeuroForm Atlas stent may be safe and effective in the treatment of wide-neck intracranial aneurysms. NeuroForm Atlas SAC is feasible for the treatment of both ruptured and unruptured wide-neck aneurysms.

Application of High-Resolution C-Arm CT Combined with Streak Metal Artifact Removal Technology for the Stent-Assisted Embolization of Intracranial Aneurysms

BACKGROUND AND PURPOSE

Metal artifacts from coils and stents limit the level of detail in C-arm CT images of stent attachment and coiling attenuation in the aneurysm neck. We evaluated the utility of high-resolution C-arm CT combined with streak metal artifact removal technology for stent-assisted embolization of intracranial aneurysms.

MATERIALS AND METHODS

From October 2017 to July 2018, the First Affiliated Hospital of Zhengzhou University treated 107 patients with intracranial aneurysms (118 aneurysms in total) with stent-assisted embolization. Conventional C-arm CT and high-resolution C-arm CT scanning of the stented area were performed during and after treatment. 3D images were reconstructed with and without streak metal artifact removal techniques. Subsequently, the image quality was compared. The reconstructed images indicated the stent deployment degree and packing density. Follow-up assessments included clinical and angiographic outcomes and complications.

RESULTS

In total, 118 aneurysms were successfully embolized using 118 stents. Image quality was significantly higher (P < .05) with high-resolution C-arm CT combined with streak metal artifact removal reconstruction. Streak metal artifact removal reconstruction and 2D angiography at working angles showed incomplete deployment of 6 stents and incomplete aneurysm embolization of 15 patients, which were subsequently resolved. One case of hemorrhage was noted postoperatively. Follow-up of 93 patients at 6-13 months indicated 3 cases of aneurysm recurrence.

CONCLUSIONS

High-resolution C-arm CT combined with the streak metal artifact removal technique effectively reduced metal artifacts from stents and coils during aneurysm embolization. This method can help physicians determine the extent of stent deployment and the packing density of coils and thus potentially reduce complications and aneurysm recurrence.

Safety and Long-term Efficacy of Stent-assisted Coiling for the Treatment of Complex Posterior Cerebral Artery Aneurysms

OBJECTIVE

To evaluate the safety and long-term efficacy of stent-assisted coiling for the treatment of complex posterior cerebral artery (PCA) aneurysms.

METHODS

Angiographic and clinical data of 23 patients harboring 23 complex PCA aneurysms treated with stent-assisted coiling from March 2010 to March 2017 were retrospectively reviewed.

RESULTS

In this study 8 (34.8%) aneurysms were located at the P1 segment, 7 (30.4%) at the junction of P1 and P2 segments (P1-2), and 8 (34.8%) at the P2 segment. The aneurysms were ruptured in 7 cases (30.4%). Thirteen were dissecting in nature, while the other 10 were classical saccular aneurysms. Of the patients, 5 (21.7%) had of history of recent head trauma, immediate angiographic results were Raymond class I in 5 (21.7%) cases, Raymond class II in 8 (34.8%), and Raymond class III in 10 (43.5%). Perioperative complications occurred in one case with occlusion of the PA due to acute in-stent thrombosis without any neurologic deficit at discharge. The last angiographic follow-up (mean 18.7 months) results demonstrated complete aneurysmal occlusion in 20 (87.0%) cases, PA occlusion in 1 (4.3%) and recurrence in 2 (8.7%). Of the two patients with aneurysm recurrence, one was treated by PA occlusion, and the other was treated with two overlapping stents. Clinical follow-up (mean 58.3 months) was available for all 23 patients, 22 (95.7%) patients had good neurologic outcomes (mRS score 0-2), and 1 (4.3%) patient died 7 months after the procedure for unknown reasons.

CONCLUSION

Stent-assisted coiling for the treatment of complex PCA aneurysms is safe and durable with a relatively low rate of complication and a relatively high rate of complete occlusion at long-term follow-up and is a promising alternative strategy for the reconstruction of the PCA.

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.

Efficacy of LVIS vs. Enterprise Stent for Endovascular Treatment of Medium-Sized Intracranial Aneurysms: A Hemodynamic Comparison Study

Background: We conducted a computational fluid dynamics (CFD) study and compared the treatment of medium-sized intracranial aneurysms with LVIS and Enterprise stent-assisted coil embolization (SACE) to determine the effects of hemodynamic changes caused by different stent and coil packing densities (PDs) in endovascular treatment.

Methods: We enrolled 87 consecutive patients, with 87 medium-sized intracranial aneurysms (≥7, ≤ 12 mm), who underwent LVIS or Enterprise SACE. Aneurysms treated with LVIS SACE were allocated to the LVIS group, and the remainder were allocated to the Enterprise group. CFD were performed to assess hemodynamic alterations between before treatment, after stent deployment, and after SACE.

Results: One aneurysm recanalized in the LVIS group (n = 42), and five recanalized in the Enterprise group (n = 45) (recanalization rate: 2.4 vs. 11.1%, respectively; P = 0.108). Higher complete obliteration rate (P = 0.069) was found in the LVIS group. Velocity at the neck plane showed a greater reduction ratio than velocity and WSS of the aneurysm in both groups after stent deployment, while velocity and WSS of the aneurysm showed a greater reduction ratio after coil placement. Further, there was a greater reduction in velocity at the neck plane (59.52 vs. 39.81%), aneurysmal velocity (88.46 vs. 69.45%), and wall shear stress (WSS) (85.45 vs. 69.49%) on the aneurysm in the LVIS group (P < 0.001 for all). Specifically, the reduction ratio of velocity at the neck plane showed significant difference between the groups in the multivariate analysis (P = 0.013).

Conclusions : LVIS SACE showed a lower recanalization for endovascular treatment of medium-sized intracranial aneurysms, and the greater hemodynamic alterations might be the key factors.

Small ruptured and unruptured complex cerebral aneurysms: Single center experience of low-profile visualized intraluminal support stent

Objectives:

Even though low-profile visualized intraluminal support (LVIS) device is used extensively currently and provide intraluminal support in complex cerebral aneurysm embolization, only few studies have reported its clinical results. This study presents the results of patients treated with LVIS.

Patients and methods:

Cerebral aneurysms with an undefined neck, fusiform shape, and blood blister-like aneurysms that were treated with LVIS between May 2017 and May 2019 were reviewed retrospectively.

Results:

Overall, 112 aneurysms in 104 patients were treated using LVIS, and 105 LVISs were placed. Of these, 101 aneurysms (90%) were small (< 10 mm) in size, 17 were fusiform aneurysms, and 3 were blood blister-like aneurysms. Overall, 39 patients suffered a subarachnoid hemorrhage and 65 had no bleeding history. 2 patients died of internal carotid artery (ICA) thrombosis, resulting in 1.9% mortality rate. Follow-up angiography was obtained in 68 patients (65%), and the complete obliteration rate was 98.5% in 6–12 months.

Conclusion:

The LVIS is a safe and effective treatment for small ruptured or unruptured complex intracranial aneurysms.

Endovascular treatment of middle cerebral artery aneurysm with a (LVIS) device: Comparison of LVIS stent and non-LVIS stent

Middle cerebral artery (MCA) aneurysm is a serious medical condition mainly occurring in the proximal and bifurcation tracts. Evidence has indicated that endovascular treatment is an effective surgical method for patients with MCA aneurysm. In the present study, the efficacy of endovascular treatment with low-profile visualized intraluminal support (LVIS) stent for MCA aneurysms was evaluated in comparison with that using a non-LVIS stent device. A total of 92 patients who underwent endovascular treatment of MCA aneurysms with LVIS stent or non-LVIS stent were included in the present study. The clinical presentation, aneurysmal characteristics, technical feasibility, procedural complications, as well as angiographic and clinical follow-up results were analyzed. The computed tomography scan demonstrated that endovascular treatment with LVIS stent markedly reduced pre-operative and intra-operative ruptures. It was indicated that endovascular treatment with LVIS stent resulted in less post-operative symptoms and cases of disability according to the modified Rankin scale score. In conclusion, the present outcomes provide evidence that endovascular treatment with an LVIS stent is an efficient method for the treatment of MCA aneurysm.

Endovascular Treatment of Ruptured Tiny Intracranial Aneurysms with Low-Profile Visualized Intraluminal Support Device

BACKGROUND

Ruptured tiny intracranial aneurysms (TIAs) have been challenging both for endovascular and neurosurgical interventions. Thus, we aimed to evaluate the safety and efficacy of low-profile visualized intraluminal support (LVIS) device in the treatment of ruptured TIAs (rTIAs).

MATERIAL AND METHODS

Among 761 intracranial aneurysms which were treated either surgically or endovascularly, 32 rTIAs underwent stent-assisted coiling with LVIS device between 2014 and 2017. Patient data were reviewed retrospectively. Clinical and radiological outcomes were recorded at discharge and mid-term follow-up.

RESULTS

Mean patient ages were 53 ± 14.5 years. Mean aneurysm size was 2.28 ± .53 mm (range, 1-2.9 mm) with a mean dome:neck ratio of 1.08 (range, .75-2.14). The LVIS stents were successfully implanted in all patients. Mean follow-up period was 9.3 ± 1.9 months (range, 6-15 months). Immediate angiographic evaluation demonstrated complete occlusion in 13 (40.6%) patients, while neck remnant and residual sac were observed in 12 (37.5%) and 7 (21.9%), respectively. All patients had moderate disability (mRS 2-3) at discharge. Number of aneurysms with complete occlusion significantly increased and 82.1% of the patients (23 of 28) demonstrated complete occlusion at follow-up (P = .0015). Among these, 27 had good outcome (mRS 0-1; 96.9%) with significant improvement compared to discharge (P = .0001). There was no recurrence or enlargement of the residual aneurysms. Additionally, there were no procedure-related complications except the one (3.6%) showing asymptomatic stenosis of the posterior cerebral artery in follow-up imagings.

CONCLUSIONS

Stent-assisted coiling of rTIAs with LVIS device provides high rates of technical success and complete occlusion at mid-term follow-up with an excellent safety profile.

Is Single Low-Profile Visualized Intraluminal Support (LVIS)-Assisted Coiling of Wide-Necked Ruptured Multiple Intracranial Aneurysms in One Stage Feasible?

OBJECTIVE

There is no previous reports available on stent-assisted coiling of ruptured multiple intracranial aneurysms using single Low-Profile Visualized Intraluminal Support (LVIS) in one stage. In the present study, we investigated the efficacy and feasibility of using single LVIS to bridge multiple intracranial aneurysms in one stage.

METHODS

From April 2014 to August 2016, 24 patients treated with single LVIS to bridge 2 aneurysms in one stage were reviewed. The aneurysm morphology, clinical outcome, angiographic results, progressive occlusion, recurrence, and procedure-related complications were analyzed retrospectively.

RESULTS

In the present study, middle term clinical outcome showed that 9 patients were had a modified Rankin Scale (mRS) score of 0, 11 patients had mRS 1, and 4 patients had mRS 2. A total of 20 patients (83.3%) achieved a good outcome, 4 patients (16.7%) had poor outcomes, and 7 of 18 patients (38.9%) displayed improved clinical neurologic status in long-term follow-up. Immediate angiographic results postprocedure showed Raymond Scale (RS) I in 33 aneurysms (68.8%), RS II in 11 aneurysms (22.9%), and RS III in 4 aneurysms (8.3%). The angiographic follow-up results showed RS I in 41 aneurysms (85.4%), RS II in 5 aneurysms (10.4%), and RS III in 2 aneurysms (4.2%). Of 15 incomplete occlusion aneurysms postprocedure, 10 aneurysms (66.7%) achieved to progressed occlusion on follow-up imaging, and no recanalization or mortality occurred in this group.

CONCLUSIONS

Single LVIS bridging wide-neck ruptured multiple intracranial aneurysms was effective and feasible in one stage. However, the procedure-related complications should be emphasized and long-term follow-up requires further evaluation.

Stent-assisted coiling of cerebral aneurysms with the Neuroform Atlas stent

Objectives The Neuroform Atlas stent (AS) is the smallest intracranial stent with an open-cell design. This study reports the first clinical experience with AS. Methods All intracranial aneurysms treated by stent-assisted coiling using a single AS in a single institution were retrospectively evaluated. Patient demographics, aneurysm characteristics, angles between the parent artery and stented branch, technical success, and clinical and angiographic follow-up were analyzed. Results Fifty-five consecutive aneurysms treated with AS-assisted coiling were included. Of these, 69.1% were located distal to the circle of Willis. Technical success rate was 100%. The mean diameters of proximal and distal parent arteries were 2.62 mm (range 1.5-4.4) and 1.8 mm (range 0.8-3.5), respectively. Except for a minor stroke in a patient who completely discontinued antiplatelet therapy on postoperative day 4, there were no clinical events with permanent sequelae, and 94.1% of patients had Raymond-Roy score of 1 or 2 aneurysmal occlusion at a mean follow-up duration of 7.9 months. Although the angle between the parent artery and the stented branch increased significantly ( p < 0.001) with time, the angular change at follow-up was only 16.45 ± 11.03 degrees and was inversely correlated both with preoperative angle and the diameter of the distal parent artery ( r = -0.465 and r = -0.433, respectively, p = 0.004 for both). Conclusion AS-assisted coiling was associated with a favorable early clinical outcome and angiographic results in this series. This stent can be used for distally located aneurysms and results in minimal alteration of the arterial anatomy.

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.

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.

Progressive Occlusion of Small Saccular Aneurysms Incompletely Occluded After Stent-Assisted Coil Embolization : Analysis of Related Factors and Long-Term Outcomes

PURPOSE

Incompletely occluded aneurysms after coil embolization are subject to recanalization but occasionally progress to a totally occluded state. Deployed stents may actually promote thrombosis of coiled aneurysms. We evaluated outcomes of small aneurysms (<10 mm) wherein saccular filling with contrast medium was evident after stent-assisted coiling, assessing factors implicated in subsequent progressive occlusion.

METHODS

Between September 2012 and June 2016, a total of 463 intracranial aneurysms were treated by stent-assisted coil embolization. Of these, 132 small saccular aneurysms displayed saccular filling with contrast medium in the immediate aftermath of coiling. Progressive thrombosis was defined as complete aneurysmal occlusion at the 6‑month follow-up point. Rates of progressive occlusion and factors predisposing to this were analyzed via binary logistic regression.

RESULTS

In 101 (76.5%) of the 132 intracranial aneurysms, complete occlusion was observed in follow-up imaging studies at 6 months. Binary logistic regression analysis indicated that progressive occlusion was linked to smaller neck diameter (odds ratio [OR] = 1.533; p = 0.003), hyperlipidemia (OR = 3.329; p = 0.036) and stent type (p = 0.031). The LVIS stent is especially susceptible to progressive thrombosis, more so than Neuroform (OR = 0.098; p = 0.008) or Enterprise (OR = 0.317; p = 0.098) stents. In 57 instances of progressive thrombosis, followed for ≥12 months (mean 25.0 ± 10.7 months), 56 (98.2%) were stable, with minor recanalization noted once (1.8%) and no major recanalization.

CONCLUSION

Aneurysms associated with smaller diameter necks, hyperlipidemic states and LVIS stent deployment may be inclined to possible thrombosis, if occlusion immediately after stent-assisted coil embolization is incomplete. In such instances, excellent long-term durability is anticipated.

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.

Preliminary Experience with Stent-Assisted Coiling of Aneurysms Arising from Small (<2.5 mm) Cerebral Vessels Using The Low-Profile Visualized Intraluminal Support Device

BACKGROUND AND PURPOSE

The Low-Profile Visualized Intraluminal Support (LVIS) stent is a new device recently introduced for the treatment of wide-neck intracranial aneurysms. This single-center study presents the authors' preliminary experience using the LVIS stent to treat saccular aneurysms with parent arteries smaller than 2.5 mm.

MATERIALS AND METHODS

Aneurysms with a LVIS stent used in a small parent vessel (<2.5 mm in diameter) between October 2014 and April 2016 were included. Procedure-related complications, angiographic results, clinical outcomes, and midterm follow-up data were analyzed retrospectively.

RESULTS

A total of 22 patients was studied, including 5 ruptured and 17 unruptured aneurysms. Most of the aneurysms were located in the anterior circulation (90.9%). Stent placement in the parent arteries measuring 1.7-2.4 mm in diameter (mean, 2.1 mm) was successful in 100% of cases. Procedure-related complication developed in 1 patient (4.5%) who presented with aneurysm rupture. No permanent morbidity and mortality occurred. Immediate angiographic outcome showed complete occlusion in 8 aneurysms (36.4%), neck residual in 8 (36.4%), and residual aneurysm in 6 (27.3%). All patients underwent angiographic follow-up at a mean of 8.3 months, which revealed complete occlusion in 18 (81.8%) patients, neck remnant in 3 (13.6%), and residual sac in 1 (4.5%). No recanalization of the target aneurysm was observed. There was 1 case with asymptomatic in-stent stenosis.

CONCLUSIONS

Our preliminary results show that the deployment of LVIS stents in small vessels is feasible, safe, and effective in the midterm. Larger studies with long-term follow-up are needed to validate our promising results.

Stenting After Coiling Using a Single Microcatheter for Treatment of Ruptured Intracranial Fusiform Aneurysms with Parent Arteries Less Than 1.5 mm in Diameter

BACKGROUND

Ruptured intracranial fusiform aneurysms involving small-diameter parent arteries are difficult to treat. Parent artery occlusion is a relatively simple and reliable treatment. However, occasionally, the parent arteries have to be retained. The arrival of the low-profile stent (LVIS Jr.) has made reconstructive endovascular treatment for fusiform aneurysms involving small-diameter parent arteries possible.

CASE DESCRIPTION

This report describes an innovative method for stent-assisted coiling (stenting after coiling technique using only 1 microcatheter) and describes our initial experience and feasibility of this technique. However, this report carries all limitations of a technical case report of a single patient, including reproducibility, unknown potential of complications, absence of long-term follow-up, and comparative effectiveness or safety with current known techniques.

CONCLUSIONS

Stenting after a coiling technique using the LVIS Jr. stent provides a possible method for reconstructive endovascular treatment of intracranial fusiform aneurysms with parent arteries <1.5 mm in diameter.