Endosaccular flow disruption: where are we now?

Treatment for middle cerebral artery bifurcation aneurysms: in silico comparison of the novel Contour device and conventional flow-diverters

Endovascular treatment has become the standard therapy for cerebral aneurysms, while the effective treatment for middle cerebral artery (MCA) bifurcation aneurysms remains a challenge. Current flow-diverting techniques with endovascular coils cover the aneurysm orifice as well as adjacent vessel branches, which may lead to branch occlusion. Novel endovascular flow disruptors, such as the Contour device (Cerus Endovascular), are of great potential to eliminate the risk of branch occlusion. However, there is a lack of valid comparison between novel flow disruptors and conventional (intraluminal) flow-diverters. In this study, two in silico MCA bifurcation aneurysm models were treated by specific Contour devices and flow-diverters using fast-deployment algorithms. Computational fluid dynamic simulations were used to examine the performance and efficiency of deployed devices. Hemodynamic parameters, including aneurysm inflow and wall shear stress, were compared among each Contour device, conventional flow-diverter, and untreated condition. Our results show that the placement of devices can effectively reduce the risk of aneurysm rupture, while the deployment of a Contour device causes more flow reduction than using flow-diverters (e.g. Silk Vista Baby). Besides, the Contour device presents the flow diversion capability of targeting the aneurysm neck without occluding the daughter vessel. In summary, the in silico aneurysm models presented in this study can serve as a powerful pre-planning tool for testing new treatment techniques, optimising device deployment, and predicting the performance in patient-specific aneurysm cases. Contour device is proved to be an effective treatment of MCA bifurcation aneurysms with less daughter vessel occlusion.

WEB shape modifications: angiography-histopathology correlations in rabbits

BACKGROUND

WEB Shape Modification (WSM) over time is frequent after aneurysm treatment. In this study, we explored the relationship between histopathological changes and angiographic evolution over time in experimental aneurysms in rabbits treated with the Woven EndoBridge (WEB) procedure.

METHODS

Quantitative WSM was assessed using flat-panel computed tomography (FPCT) during follow-up by calculating height and width ratio (HR, WR), defined as the ratio between either measurement at an index time point and the measurement immediately after WEB implantation. The index time point varied from 1 day to 6 months. HR and WR were evaluated with angiographic and histopathological assessments of aneurysm healing.

RESULTS

Final HR of devices varied from 0.30 to 1.02 and final WR varied from 0.62 to 1.59. Altogether, at least 5% of HR and WR variations were observed in 37/40 (92.5%) and 28/40 (70%) WEB devices, respectively, at the time of final assessment. There was no significant correlation between complete or incomplete occlusion groups and HR or WR (p=0.15 and p=0.43). Histopathological analysis revealed a significant association between WR and aneurysm healing and fibrosis 1 month following aneurysm treatment (both p<0.05).

CONCLUSION

Using longitudinal FPCT assessment, we observed that WSM affects both the height and width of the WEB device. No significant association was found between WSM and aneurysm occlusion status. Although presumably a multifactorial phenomenon, the histopathological analysis highlighted a significant association between width variations, aneurysm healing and fibrosis in the first month following aneurysm treatment.

Management of aneurysmal recurrence after Woven EndoBridge (WEB) treatment

BACKGROUND

Around 10% of Woven EndoBridge device (WEB)-treated intracranial aneurysms will need retreatment, and it is generally believed to be more challenging than retreatment after an initial coiling. We aim to report retreatment strategies and outcomes after initial WEB embolizations.

METHODS

Databases from four treatment centers, containing consecutive aneurysms treated with a WEB between 2013 and 2022, were reviewed. Demographics, aneurysm characteristics, retreatment strategies and outcomes were collected and analyzed.

RESULTS

From a 756 WEB database, 57 aneurysms were included. The global retreatment rate was 7.5% (95% CI 5.6% to 9.4%). The retreatment rate was significantly higher in the ruptured compared with the unruptured population (13% vs 3.9%, respectively, P<0.0001). Aneurysms were retreated on average 21.2 months after the initial WEB treatment (range 4.8-70 months). Surgery was performed in 11% and endovascular treatment in 89% of cases, consisting of flow diversion (48%), stent-assisted coiling (30%), coiling (12%), and second WEB placement (10%). Imaging follow-up was available in 88% of all WEB retreatments (50/57) (average 17 months, 49% digital subtraction angiography), demonstrating complete occlusion in 56% and 'adequate' occlusion in 88%. Morbidity was 5.3% (95% CI 0% to 12.0%) and mortality 0%. No patient experienced rebleeding during the follow-up period.

CONCLUSION

The retreatment rate after an initial WEB treatment seems to compare favorably with that of coiling. Endovascular treatment of recurrence following WEB implantation is feasible in most situations; it generally requires the use of a stent and leads to a high rate of satisfactory occlusion.

Endosaccular flow disruption with the Contour Neurovascular System: angiographic and clinical results in a single-center study of 60 unruptured intracranial aneurysms

BACKGROUND

The Contour Neurovascular System is a novel device designed to treat intracranial aneurysms by intrasaccular flow disruption. We report our experience and mid-term follow-up in a series of patients treated with the Contour.

METHODS

The patients were divided into an intention to treat and a per protocol population, the latter defined by the successful implantation of the Contour device. The intention to treat population included 53 patients (30 women, mean age 56 years) with 60 unruptured intracranial aneurysms (53 in the anterior circulation and seven in the posterior circulation). There was clinical and angiographic follow-up immediate postoperatively and at 24 hours, 3 months and 1 year using the Raymond-Roy classification and the O'Kelly-Marotta grading scale.

RESULTS

The Contour was successfully implanted in 54/60 (90%) aneurysms. With regard to the angiographic follow-up, there was adequate occlusion (defined as complete occlusion or presence of a neck remnant) in 31.5% of 54 aneurysms immediately postoperatively, 62.3% (in 53/54 aneurysms) at 24 hours, 81.4% (in 43/54 aneurysms) at 3 months, and 89.3% (in 28/54 aneurysms) at 1 year. Technical complications in 60 aneurysms of the intention to treat population included two (3.3%) inadvertent detachments of the device. Thromboembolic events were observed in four of the 60 aneurysms (6.7%), with no clinical symptoms in three patients and transient morbidity in one (1.7%). No aneurysm bleeding was observed and no patient was retreated during the 1-year follow-up period. There was no permanent morbidity or mortality.

CONCLUSIONS

The Contour device is effective and safe in the treatment of intracranial aneurysms. However, more experience and long-term follow-up are needed.

Clinical experience with the Bendit steerable microcatheter: a new paradigm for endovascular treatment

BACKGROUND

Vessel tortuosity poses a challenge during endovascular treatment of neurovascular lesions. Bendit Technologies (Petah Tikva, Israel) has developed flexible, steerable microcatheters designed with unique bending and torquing capabilities.

OBJECTIVE

To describe our first-in-human trial of Bendit21.

METHODS

Bendit21 was used in our exploratory, prospective, multicenter, open-label, single-arm clinical study, and in two compassionate use cases. Procedures were conducted at four centers in Austria, Germany, Israel, and the United States between May 2021 and March 2022, in patients with neurovascular conditions. The primary endpoints were device-related safety events, successful navigation through the neurovasculature, and, when intended, successful delivery of contrast or therapy.

RESULTS

Two patients with giant aneurysms were treated successfully under compassionate use approval. The clinical study included 25 patients (mean age: 63.4±11.8 years; 32.0% female). Fourteen patients (56.0%) had aneurysms, two had arteriovenous malformations/fistulas (8.0%), one had a stroke (4.0%), four (16.0%) had intracranial stenosis, and four (16.0%) had other conditions. Bendit21 was used without a guidewire in 12/25 (48.0%) procedures. Bendit21 was successfully navigated through the vasculature without delays or spasms in all cases (100%). Contrast was delivered as intended in 7/7 (100%) cases. Therapeutic devices were delivered successfully with Bendit as intended in 14/18 (77.8%) cases; four deficiencies occurred in three patients with aneurysms, in whom delivery of coils, an intrasaccular device, or a flow diverter was attempted. There were no device-related safety events or mortalities.

CONCLUSIONS

Our initial clinical experience with the Bendit21 microcatheter demonstrates its usefulness in achieving technical success in patients with challenging neurovascular conditions.

A review and journey in intrasaccular treatment of intracranial aneurysms

The invested effort and collaboration of clinicians and medical device companies to improve occlusion rates and clinical outcomes for patients with intracranial aneurysms treated via less invasive endovascular means led to the development of the concept of intrasaccular devices. Intrasaccular devices were introduced to offer simple treatment options, offering easier navigation through difficult anatomy, simpler and quicker deployment into large and wide-neck aneurysms. Additionally, they offer easier sizing, whilst offering a wide range of options suitable for aneurysms of different sizes. The concept of most intrasaccular devices is to occupy the aneurysm neck, however offering better stability than simple coiling, therefore increasing the chance of long-term aneurysm occlusion. This is achieved without a sizable metal content within the parent vessel, contrary to flow diverters, theoretically reducing the risk of thromboembolic events. This review aims to discuss the history and latest developments of intrasaccular intracranial devices, which offer an exciting and potentially successful option for treatment of complex intracranial aneurysms.

New concept in neurovascular navigation: technical description and preclinical experience with the Bendit 17 and Bendit 21 microcatheters in a rabbit aneurysm model

BACKGROUND

Endovascular treatment of intracranial vascular diseases, such as aneurysms, is often challenged by unfavorable vascular anatomy. The Bendit Steerable Microcatheter (Bendit Technologies, Tel Aviv, Israel) has bending and torqueing capabilities designed to improve navigation and stability during device delivery, with or without a guidewire. We describe our preclinical experience with the Bendit 17 and Bendit 21 microcatheters in a rabbit aneurysm model.

METHODS

Bifurcation and side wall aneurysms were created surgically in six New Zealand rabbits. We attempted to navigate Bendit devices through the vasculature and enter the aneurysms without a guidewire. Various positions within the aneurysm were selectively explored. Angiographic imaging was used to visualize catheterization, navigation, vascular manipulations, and placement of coils, stents, and intrasaccular devices.

RESULTS

We successfully navigated the Bendit microcatheters to all aneurysms without a guidewire. We successfully recanalized a nearly occluded carotid artery and navigated the Bendit through a braided stent. In contrast, we were unable to navigate a comparator device with a guidewire as effectively as the Bendit. Coils were introduced at different locations within the aneurysm and could be pushed, pulled, and repositioned with the Bendit tip. Finally, we used the Bendit to deliver intrasaccular devices designed for terminal aneurysms to treat side wall aneurysms.

CONCLUSIONS

Bendit's bending and torqueing abilities, combined with its stability in the bent position, enable quick navigation and optimal deployment of devices. Clinical studies are necessary to determine whether these navigation advantages lead to more efficient treatment of intracranial and peripheral aneurysms.

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.

A review of technological innovations leading to modern endovascular brain aneurysm treatment

Tools and techniques utilized in endovascular brain aneurysm treatment have undergone rapid evolution in recent decades. These technique and device-level innovations have allowed for treatment of highly complex intracranial aneurysms and improved patient outcomes. We review the major innovations within neurointervention that have led to the current state of brain aneurysm treatment.

The safety and effectiveness of the Contour Neurovascular System for the treatment of wide-necked aneurysms: A systematic review and meta-analysis of early experience

BACKGROUND

The Contour is a new generation intrasaccular flow disruption tool that aims to cover the aneurysm neck and is sized according to the neck diameter. While several case series have been published, no literature review has been performed on this promising device.

OBJECTIVE

To assess the safety and effectiveness profile of the Contour Neurovascular System for wide-necked aneurysms.

METHODS

We followed the recommendations of the PRISMA checklist Four databases were searched with a supplemental manual search. All data were analyzed using R software version 4.2.1.

RESULTS

We finally included six studies with 131 treated aneurysms. The overall procedural time was 97.27 (95% CI = 70.07-124.47) minutes, ranging from 78.9 to 136.0 min. The pooled adequate occlusion rate was 84.21% (95% CI = 75.45-90.25), and the overall functional independence rate was 94.74% (87.97-97.79). The overall adverse event rate was 4.70 (95% CI = 3.24-6.76), varying among different events from 0.78 to 8.53%. Thromboembolic events were the most commonly encountered in 8.53% of the patients (95% CI = 4.78-14.74), followed by headache and minor stroke with incidence rates of 5.88 (95% CI = 2.83-11.83) and 4.35 (95% CI = 1.41-12.63), respectively. The overall procedural time in studies using the Contour system only was 86.17 (95% CI = 68.70-10.64) minutes, while it was 136 (95% CI = 90.96-181.04) in the Contour-assisted coiling procedures. However, both techniques were comparable regarding adequate occlusion rates and functional independence.

CONCLUSION

With the anticipation of future studies, the Contour Neurovascular System is a safe and effective treatment option for wide-necked intracranial aneurysms.

Treatment of Wide-Necked Cerebral Aneurysms Using the WEB Device Including Flow Alteration Assessment With Color-Coded Imaging: A Single Center Experience

Objective

The Woven EndoBridge (WEB) device (MicroVention, Tustin, CA) has extended the treatment of cerebral aneurysms. Despite the fact that the WEB device has shown promising clinical results, little is known about the caused intra-aneurysmal flow alterations. Here we present our clinical experience with the WEB, including examining various syngo iFlow (Siemens AG, Erlangen, Germany) parameters to predict aneurysm occlusion.

Methods

We reviewed the data from patients with unruptured cerebral aneurysms treated with a WEB device between 2016 and 2020. Aneurysm occlusion and complications were assessed. Furthermore, different quantitative criteria were evaluated using syngo iFlow after digital subtraction angiography.

Results

A total of 26 patients hosting 26 cerebral aneurysms met the inclusion criteria. Follow-up was available for 21 patients, with a mean of 7.3 ± 6.3 months. A total of 71.4% (n = 15) of the aneurysms included were located in the anterior and 28.6% (n = 6) in the posterior circulation. Adequate aneurysm occlusion was achieved in 85.7% (n = 18). The iFlow parameters for reduced aneurysm outflow (ID-R) differed significantly from the parameters for reduced inflow (PI-R and PI-D) (P < 0.001). The parameters did not differ significantly between adequately and insufficiently occluded aneurysms. Only a trend towards a lower ID-R of insufficiently occluded aneurysms was observed (P = 0.063), indicating a potential predictive value for insufficient aneurysmal outflow. There was no treatment-related morbidity or mortality.

Conclusions

The applied syngo iFlow parameters confirmed that flow changes induced by the WEB device significantly affect outflow compared to inflow and have potential predictive value for adequate aneurysm occlusion.

Intrasaccular neck-bridging: A technical note on Nautilus-assisted coiling of wide-necked cerebral aneurysms. Feasibility study, immediate and early angiographic results

PURPOSE

Various adjunctive devices have been reported to be helpful during the endovascular coiling of complex, wide-necked cerebral aneurysms. This study aimed to describe the utilization of a recently introduced intrasaccular neck-bridging implant specifically designed to facilitate coil embolization.

METHODS

We retrospectively reviewed eight consecutive patients who underwent treatment for intracranial aneurysms with the Nautilus intrasaccular bridging system between February 2022 to May 2022. We evaluated the angiographic appearances of treated aneurysms at the end of the procedure and early follow-up, the clinical status and complications.

RESULTS

Eight patients with eight cerebral aneurysms (3 men and 5 women, mean age 52.8 years (range 39-66) were analyzed. Five of the treated aneurysms were managed in an acute case scenario. There were no technical difficulties while executing the technique. No other procedural adverse events were documented. Immediate complete occlusion of the aneurysm was seen in 6 patients, neck remnant in 1 and stable aneurysm reperfusion in one case. Early radiological follow-up was available in five patients, and the observed occlusion rates were - RR class I in all radiologically screened aneurysms.

CONCLUSION

Nautilus-assisted coil embolization represents a rapid and safe solution for complex cerebral aneurysms. In our opinion this device symbolizes a significant step forward in treating intracranial aneurysms. We believe that the technique's actual value consists of the fact that the device is fully compatible with the modern low-profile microcatheter technology and does not involve the need for antiplatelet medications.

Treatment of a ruptured fetal-type posterior communicating aneurysm with a combined approach using the new contour neurovascular system

Fetal-type posterior communicating artery (FPCom) aneurysms are associated with higher rates of recurrence after endovascular treatment than aneurysms at other locations. We report the case of a patient with a subarachnoid haemorrhage and ruptured right-sided FPCom aneurysm. The patient underwent acute endovascular treatment with application of a novel combined approach-partial coiling to protect the dome and occlusion of the neck with a new flow-disrupter, endosaccular device, Contour (Cerus Endovascular)-as a stable, single-step treatment to prevent rebleeding in the acute stage and long-term potential recurrences.

The Safety and Effectiveness of the Contour Neurovascular System (Contour) for the Treatment of Bifurcation Aneurysms: The CERUS Study

BACKGROUND

The Contour is a novel intra-aneurysmal flow disrupting device to treat intracranial aneurysms.

OBJECTIVE

To evaluate the safety and effectiveness of the Contour device for treatment of nonruptured intracranial bifurcation aneurysms through a prospective, multicenter, single-arm study.

METHODS

Thirty-four patients were enrolled. Primary end points were successful occlusion at 6 mo for efficacy and any major stroke or nonaccidental death up to 30 d or major disabling stroke within 6 mo for safety. Secondary end points were occlusion at 12 mo, retreatment rate, procedure time, and procedure-related/device-related adverse events. Procedural and follow-up imaging was reviewed by an independent core laboratory. Adverse events were reviewed and adjudicated by a clinical events committee.

RESULTS

In total, 32 of 34 aneurysms were successfully implanted and, 2 of 34 in the intention-to-treat (ITT) group did not receive the Contour and were excluded from follow-up after 30 d. In addition, 2 of 32 were lost to angiographic follow-up and regarded as treatment failure. The primary safety end point was met in 2 patients in the ITT group. In the perprotocol (PP) group, complete occlusion was seen in 14 of 32 (44%) at 6 mo and 22 of 32 (69%) at 12 mo. Adequate occlusion (Raymond-Roy [RR] 1 and 2) was reached in 84% at a last available follow-up. One patient from the ITT group and 1 from the PP group received additional treatment during follow-up.

CONCLUSION

The Contour seems to be both safe and effective in the treatment of intracranial bifurcation aneurysms.

A comparison between the CS-TOF and the CTA/DSA for WEB device management

PURPOSE

There is no study on the role of three-dimensional compressed sensing time of flight MR angiography (3D-CS-TOF) in the management of the WEB device. We evaluated the efficacy of 3-tesla 3D-CS-TOF for the management and follow-up of the WEB device implantations.

MATERIALS AND METHODS

Seventy-three aneurysms of 69 patients treated with the WEB device were retrospectively examined. Morphological parameters and embolization results of the aneurysms were assessed and compared on 3D-CS-TOF, CTA, and DSA images.

RESULTS

Occluded, neck remnant, and recurrent aneurysms were observed in 61 (83.6%), 7 (9.6%), and 5 (6.8%) aneurysms, respectively. Inter- and intra-reader agreement values related to aneurysm size measurements were perfect. Aneurysms size, age, and proximal vessel tortuosity were negatively correlated with the visibility of the aneurysms and parent vessels on 3D-CS-TOF images (p = 0.043; p = 0.032; p < 0.001, respectively). Subarachnoid hemorrhage and age are associated with 3D-CS-TOF artifacts (p = 0.031; p = 0.005, respectively). 3D-CS-TOF findings are in perfect agreement with DSA or CT angiography (CTA) results (p < 0.001).

CONCLUSION

According to our results, 3D-CS-TOF can be an easy, fast, and reliable alternative for the management or follow-up of WEB assisted embolization.

Indirect Flow Diversion for Off-Centered Bifurcation Aneurysms and Distant Small-Vessel Aneurysms, a Retrospective Proof of Concept Study From Five Neurovascular Centers

Background: Treatment of cerebral aneurysms using hemodynamic implants such as endosaccular flow disruptors and endoluminal flow diverters has gained significant momentum during recent years. The intended target zone of those devices is the immediate interface between aneurysm and parent vessel. The therapeutic success is based on the reduction of aneurysmal perfusion and the subsequent formation of a neointima along the surface of the implant. However, a subset of aneurysms-off-centered bifurcation aneurysms involving the origin of efferent branches and aneurysms arising from peripheral segments of small cerebral vessels-oftentimes cannot be treated via coiling or implanting a hemodynamic implant at the neck level for technical reasons. In those cases, indirect flow diversion-a flow diverter deployed in the main artery proximal to the parent vessel of the aneurysm-can be a viable treatment strategy, but clinical evidence is lacking in this regard. Materials and Methods: Five neurovascular centers contributed to this retrospective analysis of patients who were treated with indirect flow diversion. Clinical data, aneurysm characteristics, anti-platelet medication, and follow-up results, including procedural and post-procedural complications, were recorded. Results: Seventeen patients (mean age: 60.5 years, range: 35-77 years) with 17 target aneurysms (vertebrobasilar: n = 9) were treated with indirect flow diversion. The average distance between the flow-diverting stent and the aneurysm was 1.65 mm (range: 0.4-2.4 mm). In 15/17 patients (88.2%), perfusion of the aneurysm was reduced immediately after implantation. Follow-ups were available for 12 cases. Delayed opacification (OKM A3: 11.8%), reduction in size (OKM B1-3: 29.4%) and occlusion (D1: 47.1%) were observable at the latest investigation. Clinically relevant procedural complications and adverse events in the early phase and in the late subacute phase were not observed in any case. Conclusion: Our preliminary data suggest that indirect flow diversion is a safe, feasible, and effective approach to off-centered bifurcation aneurysms and distant small-vessel aneurysms. However, validation with larger studies, including long-term outcomes and optimized imaging, is warranted.

Comaneci plus Balloon-assisted Embolization of Ruptured Wide-necked Cerebral Aneurysms

BACKGROUND AND PURPOSE

Recently, avant-garde combinations of ancillary devices as an adjunct to coil embolization for acutely ruptured and wide-necked cerebral aneurysms have emerged. This study sought to investigate the feasibility, safety and durability of the simultaneous combination of temporary neck-bridging devices plus balloon-assisted coiling (BAC) to treat acutely ruptured and wide-necked cerebral aneurysms.

METHODS

A retrospective review was performed of patients with ruptured and wide-necked intracranial bifurcation aneurysms treated with temporary stent plus balloon-assisted coiling. Anatomical features, technical details, intraprocedural complications, clinical and angiographic results were reviewed. Preprocedural and follow-up clinical statuses were evaluated using the modified Rankin scale (mRS).

RESULTS

A total of 21 patients (mean age 54.5 years, range 37-72 years) were identified. The immediate postprocedural angiography revealed complete aneurysm occlusion in 85.7% (18/21) of the cases. A periprocedural complication developed in 9.5% of the cases. There was no mortality in this study. The permanent morbidity rate was 4.7%. Long-term follow-up angiography was performed in 18 of 21 patients (85.7%) (the mean follow-up period was 21 months). The rate of complete aneurysm occlusion at final follow-up was 89.4%.

CONCLUSION

The results of this study confirmed that temporary stent plus balloon-assisted coiling is a durable and relatively safe endovascular technique for the treatment of ruptured wide-necked bifurcation aneurysms located in both the posterior and anterior cerebral circulation.

Comprehensive review of the recent advances in devices for endovascular treatment of complex brain aneurysms

The International Subarachnoid Aneurysm Trial (ISAT) showed superiority for endovascular treatment of ruptured aneurysms and technology has since moved on rapidly. Many approaches and technology now exist for the endovascular management of ruptured and unruptured intracranial aneurysms, which reflects their varied nature - there is no one-size-fits-all technique. We aim to provide an overview of the various classes of device and the major developments over the past decade. Coiling is the oldest of the technology and continues to demonstrate high levels of occlusion and acceptable risks, making it the default treatment choice, particularly in the acutely ruptured aneurysm setting. Advances on coiling include the use of adjuncts such as balloons, stents and fully retrievable temporary neck-bridging devices, which have facilitated the treatment of more complex aneurysms. Flow divertors have also revolutionised complex aneurysm treatment with small added risk in acute aneurysm treatment and seek to remodel the aneurysm-vessel interface without accessing the aneurysm sac. The latest development and most promising avenue appears to be intrasaccular flow disrupting devices like WEB, Contour and Neqstent that provide excellent opportunities to treat wide neck complex aneurysm with minimal mortality and morbidity and good occlusion rates and may in future replace a significant number of stent-assisted coiling too.

Influence of operator experience on the technical and clinical results of Woven EndoBridge endovascular treatment for intracranial aneurysms

BACKGROUND & PURPOSE

The safety and efficacy of the Woven EndoBridge (WEB) device has been proven in recent multicenter trials. This study investigated whether operator experience influences WEB treatment-related outcomes.

MATERIAL AND METHODS

This was a retrospective analysis of a prospectively collected multicenter database. The data of all patients who underwent WEB treatment for an intracranial aneurysm from March 2014 to June 2020 in two high-volume centers were pooled. Operator experience was indexed by the number of WEB treatments performed previously. The primary endpoint was the overall complication rate. Secondary endpoints were long-term adequate (Raymond-Roy classification of 1-2.) angiographic occlusion, WEB-related complications, number of WEB not deployed, procedure duration, and radiation exposure (air kerma).

RESULTS

Among 237 patients (mean age 59.4 +/- 11.5 years) treated with WEB (median aneurysm diameter, 5.8 mm; interquartile range 4.5-7 mm), WEB-related complications occurred in 28 patients (11.8%) and adequate long-term occlusion was achieved for 154 aneurysms (86%). The median number of WEB treatment performed previously per operator was 20 (IQR, 9-41). The overall complication rate, WEB-related complication rate and aneurysm occlusion rate were not significantly correlated with WEB operator experience. There were also no significant correlations between the WEB operator experience and the number of WEB not deployed, procedure duration or radiation exposure.

CONCLUSION

There was no significant association between the number of WEB treatments previously performed per operator and any technical or clinical results after intracranial aneurysm treatment with WEB. These results imply a relatively short learning curve for this device in high-volume neurovascular centers.

Treatment of a middle cerebral artery bifurcation aneurysm with the novel Contour Neurovascular System compatible with 0.021″ catheters

Background

For wide-necked intracranial aneurysms, endo-saccular flow disruption can be a viable alternative to coiling or flow diverters. The Contour Neurovascular System is an intrasaccular flow diverter device targeting the neck of the aneurysm. Until now, the system had to be delivered through a 0.027″ microcatheter. We report the first implantation and follow-up of the novel Contour 021 system compatible with 0.021″ microcatheters.

Case presentation: A 54-year-old male patient presented with an unruptured right middle cerebral artery aneurysm at the right temporopolar branch. Existing medication included apixaban. An arteriogram showed a broad-based aneurysm. Due to its asymmetric geometry, neither the Woven EndoBridge nor stent-assisted coil embolisation were regarded as promising treatment strategies. To uphold the option of different treatment options, prasugrel 10 mg was initiated before treatment. Implantation was performed under general anaesthesia via femoral artery puncture. A 0.021″ Headway™ catheter was used for accessing the aneurysm. The Contour device was oversized to the equatorial plane. Deployment was successful with only one attempt without the need for re-sheathing. Follow-up catheter angiography was performed after three months, showing complete occlusion of the aneurysm. No procedure-related complications occurred.

Conclusion

The 0.021 design of the Contour enlarges the subgroup of patients that can be treated with endo-saccular devices and will enable treatment of smaller and more distal aneurysms.

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

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

Nautilus-Assisted Coiling of an Unruptured Wide-Necked Aneurysm of the Posterior Communicating Artery

A variety of recently introduced devices have allowed more complex aneurysms to be rendered for endovascular embolization. Tiny and sophisticated implants are nowadays designed to provide further either temporary or permanent remodeling of the wide-necked aneurysms and improve coil occlusion rates.^1-4 Such improvements in the technical armamentarium include the Woven EndoBridge (Sequent Medical, California, USA), the Medina Embolic Device (Medtronic, Irvine, California, USA), The Contour Neurovascular System (Cerus Endovascular, Fremont, California, USA), and pCONUS 2 HPC (Phenox, GmbH, Bohum, Germany).^5-7 Intrasaccular neck bridging is a conceptually new technique descending from the theoretical combination of intrasaccular flow diversion and temporary-stent assisted coiling.⁸ The Nautilus (EndoStream Medical, Tel Aviv, Israel) is an intrasaccular bridging device that offers complete neck reconstruction in coil embolization of wide-neck cerebral aneurysms. It has been granted a CE mark by the European Union. The detachable intrasaccular implant comprises flexible and "tornado-like"-shaped Nitinol-based layers. The device is compatible with a standard microcatheter with minimal 0.0165″ inner diameter and is fully radiopaque and fully resheathable. The device's intrasaccular nature and the fact that it does not harbor any intraluminal satellite parts suggest that the implant can be safely used in both unruptured and ruptured case scenarios without the need for dual antiplatelet therapy. This is what we consider a great advantage of the proposed technique over the alternative options of intrasaccular and intraluminal flow diversion. This technical video (Video 1) demonstrates the successful obliteration of a complex posterior communicating artery aneurysm with Nautilus-assisted endovascular coiling. To our knowledge, this is the first technical video demonstrating an in-vivo and step-by-step implementation of this novel device.

WEB device for treatment of posterior communicating artery aneurysms

BACKGROUND

Woven EndoBridge (WEB) device treatment of wide-neck bifurcation aneurysms has proved to be safe and effective, but the use of these devices in sidewall aneurysms has been reported only in a small number of case series.

OBJECTIVE

To report our results in a cohort of consecutive patients in whom a WEB device was used as first-line treatment for posterior communicating artery (PComA) aneurysms.

METHODS

We conducted a retrospective analysis of a prospectively maintained database of PComA aneurysms treated with a WEB device in our institution from June 1, 2012 to November 15, 2020. Clinical and radiological findings were evaluated at immediate and last follow-up.

RESULTS

A total of 219 aneurysms were treated with a WEB device, including 15 PComA aneurysms in 15 patients, 10 of which were ruptured. Aneurysms were wide necked, with a mean aspect ratio of 1.6 (range 0.7-3.0) and a mean neck size of 4.2 mm (range 2.6-7.4 mm). No intraoperative rupture occurred and only one thromboembolic event was noted. Among the group with at least a 3-month digital subtraction angiography (DSA) follow-up, complete and adequate occlusion were obtained in 54% and 72%, respectively (average follow-up 13 months). Re-treatment was needed for two initially ruptured aneurysms. No procedure-related morbidity or mortality was reported.

CONCLUSION

This series suggests the high safety profile of WEB devices even when used in off-label indications. Treatment with these devices seems to be a valuable strategy for ruptured wide-neck PComA aneurysms, avoiding the need for antiplatelet medication. However, occlusion rates should be investigated in further larger studies.

Combination of temporary bridging device (Comaneci) and permanent stenting in the treatment of unruptured wide neck bifurcation aneurysms

The double stent-assisted techniques for the treatment of wide neck bifurcation aneurysms (WNBAs) may be more complicating than single stent-assisted or balloon-assisted coiling. The Comaneci device (Rapid Medical, Yokneam, Israel) is a new temporary bridging device developed for covering the aneurysm neck during coiling. This new design enabled us to treat unruptured WNBAs with the use of single stent-assisted coiling instead of double stent in eight patients. At the 1-year angiographic follow-up, there was no filling in any aneurysm. There was no mortality or morbidity cases related to the procedure. In this study, we are reporting our experience of using single stent-assisted coiling combined with a Comaneci device in the treatment of unruptured WNBAs.

The Woven EndoBridge embolization device for the treatment of intracranial wide-necked bifurcation aneurysms

Wide-necked bifurcation aneurysms are common when evaluating both ruptured and unruptured intracranial aneurysms and can pose unique challenges. The Woven EndoBridge device (recently approved in the US) is specifically designed for the treatment of these aneurysms. This article serves to introduce the device to a wider audience with a thorough review of the literature, device design, indications, pre-operative evaluation, procedural usage and potential pitfalls.

Endovascular Treatment of Ruptured Wide-Necked Anterior Communicating Artery Aneurysms Using a Low-Profile Visualized Intraluminal Support (LVIS) Device

Objective: To evaluate the safety and efficacy of low-profile visualized intraluminal support (LVIS) stent-assisted coiling for the treatment of ruptured wide-necked anterior communicating artery (ACoA) aneurysms.

Methods: The clinical and angiographic data of 31 acutely ruptured wide-necked ACoA aneurysms treated with LVIS stent-assisted coiling between January 2014 and December 2018 were retrospectively reviewed.

Results: All stents were successfully deployed. The immediate angiographic results were modified Raymond-Roy class I in 27 cases, modified Raymond-Roy class II in 2 cases, and modified Raymond-Roy class IIIa in 2 cases. Intraoperative thrombosis and postoperative aneurysmal rebleeding occurred in one case each. Two patients (6.5%) who were admitted due to poor clinical grade conditions died during hospital admission as a result of initial bleeding. Angiographic follow-up (mean: 12.9 months) was performed for 26 patients, the results of which demonstrated that 25 aneurysms were completely occluded and one was class II. The last clinical follow-up (mean: 25.3 months) outcomes demonstrated that 27 patients had favorable clinical outcomes and two had poor clinical outcomes.

Conclusion: LVIS stent-assisted coiling for ruptured wide-necked ACoA aneurysms was safe and effective, with a relatively low rate of perioperative complications and a high rate of complete occlusion at follow-up.

[New trends in the treatment of bifurcation aneurysms]

CLINICAL ISSUE

Intracranial aneurysms most commonly occur at bifurcation sites. In case of dealing with broad based aneurysms, the risk of accidental vessel occlusion during embolization should not be underestimated. Therefore, several devices are available, e.g. WEB device and barrelsStent. Besides that, a special technique gives the opportunity to place two stents into each other or next to each other into both branches of a bifurcation. Over 300 patients included in 18 studies were treated with Y‑stenting (e.g., Medline/Embase) showing a good clinical outcome in 92%. A complete occlusion was achieved in 91%. The rate of neurologic deficits was 4%, the procedure-caused mortality was 2%. Furthermore, 12% of the patients sustained a stroke during the intervention. Ruptured aneurysm was found in 19%.

CONCLUSION

All in all, a high occlusion rate and a low rate of mortality and stroke were shown by using Y‑stenting.

Advances in endovascular aneurysm management: flow modulation techniques with braided mesh devices

Flow diverters and flow disruption technology, alongside nuanced endovascular techniques, have ushered in a new era of treating cerebral aneurysms. Here, we provide an overview of the latest flow modulation devices and highlight their clinical applications and outcomes.

Rescue of migrated Woven Endobridge devices using a stent-retriever-technique in a porcine model

PURPOSE

The Woven Endobridge device (WEB) has become widely applied for the treatment of intracranial aneurysms. Complications are rare, however, especially dislocations and migrations can potentially increase poor clinical outcome. The aim of this study was to assess the feasibility and effectiveness of rescuing migrated Woven Endobridges using different stent retrievers.

METHODS

In a porcine model, Woven Endobridges of different sizes (SLS 4, SLS 7, SL 5 × 3, SL 4 × 3) were placed into the axillary arteries. By means of two different stent retrievers (Solitaire Platinum and 3D Revascularization Device), a total of 20 rescue maneuvers were performed. For this purpose, the retrievers were deployed distally of the migrated Woven Endobridges. After retracting the stent retrievers partially, the Woven Endobridges were trapped within the microcatheter. Rescue rates, time, attempts and complications were assessed.

RESULTS

Successful rescue of the migrated Woven Endobridges was observed in all cases (100%). Rescue was slightly faster (177.8 ± 72.8 s vs. 223.4 ± 104.1 s) with fewer attempts (1.5 ± 0.8 vs. 1.8 ± 0.9) when using the 3D Revascularization Device compared to the Solitaire Platinum. However, there were no significant differences (p = 0.327; p = 0.554). Migration of the Woven Endobridges during rescue was seen with both stent retrievers in a comparable frequency (p = 0.642). Further complications, such as entrapment of the stent-retriever-WovenEndobridge-complex at the intermediate catheter, vasospasm, perforation or dissection, were not observed.

CONCLUSIONS

Rescue of migrated Woven Endobridges using stent retrievers is a feasible and effective method. Rescue rates, times and attempts with the Solitaire Platinum and 3D Revascularization Device are comparable with each other.

Different Rescue Approaches of Migrated Woven Endobridge (WEB) Devices: an Animal Study

Purpose

Treatment of wide-necked intracranial aneurysms using the Woven Endobridge (WEB) device has become broadly accepted. Feared complications with the potential of increased poor clinical outcome include dislocations and migration of the device. This study was carried out to determine the effectiveness of a variety of different strategies to rescue migrated WEB devices.

Methods

In a porcine model, WEB devices of different sizes (SL [single layer] 3.5 × 2mm and SL 4.0 × 3 mm, SL 8 × 5 mm and SLS 8 mm [single layer spherical]) were placed into both the subclavian and axillary arteries. A total of 32 rescue maneuvers (8 per rescue device) were performed. Small WEBs were rescued using reperfusion catheters (RC) (SOFIA Plus and JET 7), larger WEBs were rescued using dedicated rescue devices (Microsnare and Alligator). Rescue rates, times, attempts and complications were assessed.

Results

Rescue attempts of migrated WEBs were successful in all cases (100%). Rescue time (p = 0.421) and attempts (p = 0.619) of small WEBs using RCs were comparable without significant differences. Aspiration alone was not successful for larger WEBs. Rescue of larger WEBs was slightly faster (122.75 ± 41.15 s vs. 137.50 ± 54.46 s) with fewer attempts (1 vs. 1.37) when using the Microsnare compared to the Alligator device. Complications such as entrapment of the WEB in the RCs, vasospasm, perforation, or dissection were not observed.

Conclusion

Rescue of migrated WEB devices is a feasible and effective method and 100% successful rescue rates and appropriate rescue times can be achieved for small WEBs using RCs and for larger WEBs using dedicated rescue devices (Microsnare and Alligator).

Y-Stenting Versus PulseRider-Assisted Coiling in the Treatment of Wide-Neck Bifurcation Aneurysms: Role of Anatomical Features on Midterm Results

BACKGROUND

Y-stenting is an effective but challenging approach for wide-neck aneurysms. PulseRider (PR) (Pulsar/Cerenovus) is a new device designed to provide scaffolding during coiling but has never been compared with other techniques.

OBJECTIVE

To compare the immediate and 6-mo results of Y-stenting vs PR assisted coiling.

METHODS

A total of 105 consecutive patients were retrospectively divided into 2 groups (73 Y-stenting and 32 PR). All underwent angiographic 6-mo follow-up. We evaluated if some anatomical features could influence treatment results.

RESULTS

The groups were homogeneous. Immediate adequate occlusions as well as complication rates were similar in Y-stenting and PR group (94.5% vs 96.9% and 8.2% vs 6.2%, respectively). At 6 mo, adequate occlusion was 93.1% after Y-stenting and 84.3% after PR (P = .28), complete occlusion was significantly higher after Y-stenting: 90.3% vs 62.5% (P = .0017). Occlusion grade worsening occurred in 6.9% of Y-stenting and 18.7% of PR patients (P = .09).

Neck size was associated with occlusion grade in both groups. Maximal aneurysm size was associated with occlusion grade in the PR group (P = .023) but not in the Y-stenting group (P = .06). After PR, 6-mo occlusion rate was higher in small (&lt; 10 mm) than in large aneurysms (P = .0094); this was not observed after Y-stenting (P = .54).

Location did not significantly affect the mid-term occlusion rate in both the groups. After PR, occlusion was more stable in basilar than anterior or middle cerebral artery aneurysms.

CONCLUSION

Y-stenting and PR are both effective with similar immediate and mid-term results. However, treatment stability seems higher after Y-stenting. Aneurysm size seems to negatively affect PR results.