Surpass flow diverter in the treatment of intracranial aneurysms: a prospective multicenter study

A Combination Technique of N-butyl-2-cyanoacrylate and Minimal Coils with Flow Control for Parent Artery Occlusion of a Giant Internal Carotid Artery Aneurysm: A Technical Note

Parent artery occlusion for large or giant internal carotid artery aneurysms remains a necessary procedure in the era of flow diverters. Endovascular parent artery occlusion is currently performed using detachable balloons or coils, which are difficult to obtain or costly. At our institution, we have devised a technique for combining n-butyl-2-cyanoacrylate and coils with flow control to solve this problem. Patients who underwent parent artery occlusion for large or giant internal carotid artery aneurysms with a follow-up period of more than 12 months were included. Imaging outcomes were evaluated for complete or incomplete aneurysmal occlusion and with or without aneurysmal shrinkage. The clinical outcome was based on changes in the modified Rankin Scale. Ten patients (ten aneurysms) were included. Their average age and average follow-up period were 68.4 years and 36 months, respectively. Complete occlusion and favorable clinical outcome were observed in all cases. The parent artery occlusion using a combination of coils and n-butyl-2-cyanoacrylate with flow control technique is effective for both imaging and clinical outcomes.

Flow Diversion for Endovascular Treatment of Intracranial Aneurysms: Past, Present, and Future Directions

Flow diversion for intracranial aneurysms emerged as an efficacious and durable treatment option over the last two decades. In a paradigm shift from intrasaccular aneurysm embolization to parent vessel remodeling as the mechanism of action, the proliferation of flow-diverting devices has enabled the treatment of many aneurysms previously considered untreatable. In this review, we review the history and development of flow diverters, highlight the pivotal clinical trials leading to their regulatory approval, review current devices including endoluminal and intrasaccular flow diverters, and discuss current and expanding indications for their use. Areas of clinical equipoise, including ruptured aneurysms and wide-neck bifurcation aneurysms, are summarized with a focus on flow diverters for these pathologies. Finally, we discuss future directions in flow diversion technology including bioresorbable flow diverters, transcriptomics and radiogenomics, and machine learning and artificial intelligence.

Safety and anatomical outcome analysis after flow diverter coverage of the anterior cerebral artery

OBJECTIVES

Few studies on ischemic complications and flow changes after a flow diverter covering the anterior cerebral artery. The purpose of the study was to explore the ischemic complications and anatomical alterations associated with the flow diverter after it covers the anterior cerebral artery.

MATERIALS AND METHODS

In this single-center study, patients treated with FD covering the anterior cerebral artery at the First Affiliated Hospital of Zhengzhou University were retrospectively collected. The primary endpoint was ischemic complications related to the anterior cerebral artery. Secondary endpoints were anatomical changes in the anterior cerebral artery postoperatively and at follow-up.

RESULTS

A total of 59 patients were included in this study. Four (6.8%) patients presented with ischemic stroke symptoms. Immediately after the procedure, complete occlusion of A1 and decreased blood flow was observed in 13 (22.0%) and 21 patients (35.6%), respectively. At follow-up, A1 artery was occluded in 34 patients (57.6%) and decreased blood flow was observed in 10 patients (16.9%). Symptoms of neurological deficits related to the anterior cerebral artery were not observed in all patients at follow-up.

CONCLUSION

Coverage of A1 is safe, with a low incidence of ischemic stroke, when using an FD to treat aneurysms. Risk of reduced perfusion of the anterior cerebral artery postoperatively even if the anterior communicating artery is open. In cases with A1 occlusion, the blood flow in the distal the anterior cerebral artery can be adequately compensated by opening the anterior communicating artery and good vascular anastomoses.

Risk factor analysis of changes in blood flow in the A1 segment of the anterior cerebral artery after flow-diverter coverage of it

Few studies have explored the effect of a flow-diverter device (FD) on blood flow in the A1 segment of the anterior cerebral artery (ACA), after treatment of intracranial aneurysms in the bifurcation region of the internal carotid artery (ICA). The main objective of this article is to investigate the factors that affect A1 blood flow after FD covers the A1 artery. This is a single-center, retrospective study. Data were collected retrospectively from our center, and patients whose FDs were placed for treatment from the terminal of the ICA to the M1 segment were analyzed. A total of 42 patients were included in the study. Immediate post-procedural angiography following device placement revealed decreased blood flow in the A1 of 15 (35.7%) patients and complete occlusion of the A1 segment in 11 (26.2%) patients. During an average follow-up period of 9.8 months, the A1 segment was ultimately occluded in 25 patients (59.5%) and decreased blood flow in 4 patients (9.5%). When using FD to cover the A1 artery for the treatment of intracranial aneurysms, patients with preoperative opening of the anterior communicating artery (AcomA) are more prone to occlusion or decreased blood flow of the A1 artery, compared to patients without opening.

Hemodynamic alterations of flow diverters on aneurysms at the fetal posterior communicating artery: A simulation study using CFD to compare the surpass streamline, pipeline flex, and tubridge devices

PURPOSE

Traditional flow diverters (FDs) for treating aneurysms at the fetal posterior communicating artery are unsatisfactory. Surpass Streamline is a novel FD with different mesh characteristics; however, the outcomes for such aneurysms remain unclear. This study aimed to compare hemodynamic alterations induced by Surpass Streamline, Pipeline Flex, and Tubridge devices and explore possible strategies for aneurysms at the fetal posterior communicating artery.

METHODS

Two simulated aneurysms (Case 1, Case 2) were constructed from digital subtraction angiography (DSA). The three FDs were virtually deployed, and hemodynamic analysis based on computational fluid dynamics was performed. Hemodynamic parameters, including the sac-averaged velocity magnitude (Velocity), high-flow volume (HFV), and wall shear stress (WSS), were compared between each FD and the untreated model (control). Surpass Streamline was performed in real life for two aneurysms and the clinical outcomes were collected for analysis.

RESULTS

Compared to the control, the Surpass resulted in the most significant reduction in flow. In Case 1, the Velocity, HFV, and WSS were reduced by 51.6%, 78.1%, and 64.3%, respectively. In Case 2, the Velocity, HFV, and WSS were reduced by 48.0%, 81.1%, and 65.3%, respectively. Tubridge showed slightly larger changes in hemodynamic parameters than Pipeline. In addition, our analysis suggested that metal coverage was correlated with the WSS, Velocity, and HFV. The postoperative DSA showed that the aneurysm was nearly occluded in Case 1 and decreased in Case 2.

CONCLUSION

Compared to that with the Pipeline and Tubridge, the Surpass resulted in the greatest reduction in hemodynamic parameters and might be effective for aneurysms at the fetal posterior communicating artery. Virtual FD deployment and computational fluid dynamics analysis may be used to predict the treatment outcomes.

Flow-diverter stents combined with flow-T stenting-assisted coiling for the treatment of a large basilar apex aneurysm: a case report with a 9-month follow-up

Background

Endovascular or surgical treatment of wide-neck, large basilar apex aneurysms is challenging. We present a novel concept for the treatment of complex basilar apex aneurysms using flow-diverter devices combined with the flow-T stenting-assisted coiling technique. Assess the efficacy and safety profile of the technique in this complex aneurysm.

Case description

A patient with multiple unruptured intracranial aneurysms underwent staged treatment. A large basilar apex aneurysm was treated with a flow-diverter stent combined with a flow-T stenting-assisted coiling technique in the first stage, and a giant supraclinoid aneurysm was treated with a flow-diverter stent applied in the second stage. Clinical presentations, technical details, intra- and perioperative complications, and clinical and angiographic outcomes were recorded, with a 9-month follow-up.

Results

The patient achieved full neurologic recovery postoperatively. Cerebral angiography performed postoperatively showed revascularization, good laminar flow, and no in-stent or adjacent stenosis.

Conclusion

Flow-diverter stents combined with flow-T stenting-assisted coiling for the treatment of giant basilar apex aneurysms is a feasible technique with efficacy demonstrated at a 9-month follow-up. Staged endovascular treatment of multiple intracranial aneurysms may be a safe and viable option.

Flow Diversion for the Treatment of Intracranial Aneurysms in a Peruvian Cohort: Experiences from a Limited-Resource Setting and Barriers to Implementation

BACKGROUND

Stenting with flow diverter devices (FDDs) has increasingly emerged as a treatment for intracranial aneurysms. The use of FDDs in the developing world has not been described.

METHODS

A retrospective review was performed of a cohort of patients who underwent flow diversion at 4 tertiary-care centers in Lima, Peru between January 2017 and June 2021. Demographics, clinical features, and aneurysm morphology were evaluated. Clinical outcomes were observed 3 months after discharge and occlusion rates were assessed 12 months after treatment.

RESULTS

Sixty-nine patients (mean age, 46 ±14.5 years; 17% female) were treated with FDDs; 4% (n = 3) of the treated aneurysms were ruptured. Most aneurysms were saccular (n = 65; 94%), <10 mm in maximum size (n = 60; 87%), and located in the anterior circulation (n = 67; 97%). Minor complications, such as groin hematoma, occurred in 7 cases. No serious complications or deaths occurred. Patients' functional status was excellent (modified Rankin Scale score 0-1) in 99% (n = 66) at discharge and 100% (n = 67) at 3 months. Although some patients were lost to follow-up, complete occlusion was seen in 76% (n = 31) of 41 treated patients at 12 months.

CONCLUSIONS

We report the largest multicenter experience of FDDs for cerebral aneurysm treatment in Peru, with reasonable outcomes that are comparable to other settings despite various challenges, suboptimal circumstances, and lack of resources.

No Delayed Ruptures on Long-Term Follow-Up of a Case Series of Persistently Filling Saccular Internal Carotid Artery Aneurysms After Flow Diversion With the Pipeline Embolization Device

BACKGROUND AND OBJECTIVES

Flow diversion of intracranial aneurysms results in high occlusion rates. However, 10% to 20% remain persistently filling at 1 year. Often, these are retreated, but benefits of retreatment are not well established. A better understanding of the long-term rupture risk of persistently filling aneurysms after flow diversion is needed.

METHODS

Our institutional database of 974 flow diversion cases was queried for persistently filling saccular aneurysms of the clinoidal, ophthalmic, and communicating segments of the internal carotid artery treated with the pipeline embolization device (PED, Medtronic). Persistent filling was defined as continued flow into the aneurysm on 1 year catheter angiogram. The clinical record was queried for retreatments and delayed ruptures. Clinical follow-up was required for at least 2 years.

RESULTS

Ninety-four persistent aneurysms were identified. The average untreated aneurysm size was 5.6 mm. A branch vessel originated separately in 55% of cases from the body of the aneurysm in 10.6% of cases and from the neck in 34% of cases. Eighteen percent of aneurysms demonstrated >95% filling at 1 year, and 61% were filling 5% to 95% of their original size. The mean follow-up time was 4.9 years, including 41 cases with >5 years. No retreatment was undertaken in 91.5% of aneurysms. There were no cases of delayed subarachnoid hemorrhage.

CONCLUSION

Among saccular internal carotid artery aneurysms treated with PED that demonstrated persistent aneurysm filling at 1 year, there were no instances of delayed rupture on long-term follow-up. These data suggest that observation may be appropriate for continued aneurysm filling at least in the first several years after PED placement.

Surpass Intracranial Aneurysm Embolization System Pivotal Trial to Treat Large or Giant Wide-Neck Aneurysms - SCENT: 3-year outcomes

BACKGROUND

To report the 3-year safety and effectiveness of the Surpass Streamline flow diverter in the SCENT trial (Surpass Intracranial Aneurysm Embolization System Pivotal Trial to Treat Large or Giant Wide-Neck Aneurysms).

METHODS

The Surpass Streamline flow diverter device was evaluated in a multicenter, prospective, single-arm, non-randomized interventional trial including patients with uncoilable or previously treated but failed aneurysms of the intracranial internal carotid artery. 3-year outcomes were tabulated with descriptive statistics and compared with 1-year outcomes.

RESULTS

Of 180 patients in the modified intent-to-treat (mITT) cohort, 36-month clinical and angiographic follow-up was available in 134 and 117 cases, respectively. Effectiveness endpoint of complete aneurysm occlusion without clinically significant stenosis or retreatment was met in 71.8% (79/110, 95% CI 62.4% to 80.0%) of cases. Safety composite endpoint was 12.2% (22/180) over the 3-year period, with two major safety events (ipsilateral ischemic strokes) occurring between 12-36 months. Complete aneurysm occlusion was noted in 77.8% (91/117), and 99.1% (116/117) of the patients demonstrated adequate aneurysm occlusion (complete occlusion or neck residual). There were four cases (2.2%) of aneurysm rupture, all occurring within the first month of the index procedure. Target aneurysm retreatment rate was 2.8% (5/180).

CONCLUSION

The present findings support the long-term safety and effectiveness of the Surpass Streamline flow diverter device.

TRIAL REGISTRATION

NCT01716117.

Safety and efficacy of the surpass streamline for intracranial aneurysms (SESSIA): A multi-center US experience pooled analysis

BACKGROUND AND PURPOSE

Flow diversion has established as standard treatment for intracranial aneurysms, the Surpass Streamline is the only FDA-approved braided cobalt/chromium alloy implant with 72-96 wires. We aimed to determine the safety and efficacy of the Surpass in a post-marketing large United States cohort.

MATERIALS AND METHODS

This is a retrospective multicenter study of consecutive patients treated with the Surpass for intracranial aneurysms between 2018 and 2021. Baseline demographics, comorbidities, and aneurysm characteristics were collected. Efficacy endpoint included aneurysm occlusion on radiographic follow-up. Safety endpoints were major ipsilateral ischemic stroke or treatment-related death.

RESULTS

A total of 277 patients with 314 aneurysms were included. Median age was 60 years, 202 (73%) patients were females. Hypertension was the most common comorbidity in 156 (56%) patients. The most common location of the aneurysms was the anterior circulation in 89% (279/314). Mean aneurysm dome width was 5.77 ± 4.75 mm, neck width was 4.22 ± 3.83 mm, and dome/neck ratio was 1.63 ± 1.26. Small-sized aneurysms were 185 (59%). Single device was used in 94% of the patients, mean number of devices per patient was 1.06. At final follow-up, complete obliteration rate was 81% (194/239). Major stroke and death were encountered in 7 (3%) and 6 (2%) cases, respectively.

CONCLUSION

This is the largest cohort study using a 72-96 wire flow diverter. The Surpass Streamline demonstrated a favorable safety and efficacy profile, making it a valuable option for treating not only large but also wide-necked small and medium-sized intracranial aneurysms.

Derivo embolization device for intracranial aneurysms: a Spanish multicenter retrospective study

BACKGROUND

Flow diverters have emerged in recent years as a safe and effective treatment for intracranial aneurysms, with expanding indications. The Derivo embolization device (DED) is a second-generation flow diverter with a surface finish that may reduce thrombogenicity. We report our multicenter experience evaluating its safety and efficacy.

METHODS

We retrospectively analyzed all patients treated with the DED in eight centers in Spain between 2016 and 2020. Demographics, clinical data, procedural complications, morbidity and aneurysm occlusion rates were collected.

RESULTS

A total of 209 patients with 250 aneurysms were treated (77.5% women). The majority of aneurysms were located in the internal carotid artery (86.8%) and most (69.2%) were small (<10 mm) with a median maximum diameter of 5.85 mm and median neck size of 4 mm. DED deployment was successful in all cases, despite two malfunctioning devices (1%). Major complications occurred in nine patients (4.3%), while mild neurologic clinical events were registered in 23 (11%); four patients died (1.9%). A total of 194 aneurysms had an angiographic follow-up at 6 months and showed complete aneurysm occlusion in 75% of cases. Twelve-month follow-up was available for 112 of the treated aneurysms, with a total occlusion rate of 83%.

CONCLUSION

The DED is a second-generation surface-modified flow diverter that presents an option for treatment of intracranial aneurysms with comparable safety and efficacy to other available flow diverter devices. Nonetheless, risks are not negligible, and must be balanced against the natural history risk of cerebral aneurysms, considering the tendency to widen indications for treatment of smaller and less complex lesions in day-to-day use.

Flow diversion for compressive unruptured internal carotid artery aneurysms with neuro-ophthalmological symptoms: a systematic review and meta-analysis

BACKGROUND

Data on the safety and efficacy of flow diverters (FD) for the treatment of unruptured internal carotid artery (ICA) aneurysms with compressive neuro-ophthalmological symptoms (NOS) are scarce and comprise mainly small case series.

METHODS

We performed a search of three databases and included series with ≥10 patients, with unruptured aneurysms of the ICA and NOS, treated with FD. Random-effects analysis of treatment results and safety was performed.

RESULTS

A total of 22 studies reporting on 594 patients were included. Pooled proportions of NOS recovery, improvement, transient and permanent worsening were: 47.4% (95% CI 35.0% to 60.1%); 74.5% (95% CI 67.9% to 80.2%); 7.1% (95% CI 3.3% to 14.7%); and 4.9% (95% CI 3.2% to 7.4%), respectively. Rates of complete recovery and improvement in patients with isolated visual symptoms were 30.6% (95% CI 12.5% to 57.7%) and 56.6% (95% CI 42.3% to 69.9%). Isolated oculomotor symptoms recovered completely in 47.8% (95% CI 29.9% to 66.3%) and improved in 78% (95% CI 69.2% to 84.9%). Morbidity occurred in 5% (95% CI 2.8% to 9%) and mortality in 3.9% (95% CI 2% to 7.5%) of patients. An increased likelihood of symptom improvement was observed when treatment was performed early (<1 month) after symptom onset (OR=11.22, 95% CI 3.9% to 32.5%).

CONCLUSION

Flow diversion promotes recovery or improvement of compressive symptoms in a large proportion of patients but is associated with significant rates of morbidity and mortality. Transient and permanent NOS worsening is not uncommon. Early treatment is of utmost importance, as it increases the likelihood of symptom improvement more than 10-fold.

High-frequency optical coherence tomography predictors of aneurysm occlusion following flow diverter treatment in a preclinical model

BACKGROUND

High-frequency optical coherence tomography (HF-OCT) is an intravascular imaging method that allows for volumetric imaging of flow diverters in vivo.

OBJECTIVE

To examine the hypothesis that a threshold for both volume and area of communicating malapposition can be predictive of early aneurysm occlusion.

METHODS

Fifty-two rabbits underwent elastase aneurysm formation, followed by treatment with a flow diverter. At the time of implant, HF-OCT was acquired to study the rate and degree of communicating malapposition. Treated aneurysms were allowed to heal for either 90 or 180 days and euthanized following catheter angiography. Healing was dichotomized into aneurysm remnant or neck remnant/complete occlusion. Communicating malapposition was measured by HF-OCT using a semi-automatic algorithm able to detect any points where the flow diverter was more than 50 µm from the vessel wall. This was then summed across image slices to either a volume or area. Finally, a subsampled population was used to train a statistical classifier for the larger dataset.

RESULTS

No difference in occlusion rate was found between device type or follow-up time (p=0.28 and p=0.67, respectively). Both volume and area of malapposition were significantly lower in aneurysms with a good outcome (p<0.001, both). From the statistical model, a volume of less than 0.56 mm3 or a normalized area less than 0.69 as quantified by HF-OCT was predictive of occlusion (p<0.001, each).

CONCLUSIONS

HF-OCT allows for measurements of both volume and area of malapposition and, from these measurements, an accurate prediction for early aneurysm occlusion can be made.

Comparison of pipeline embolization device, flow re-direction endoluminal device and surpass flow diverters in the treatment of intracerebral aneurysms

OBJECTIVES

The use of flow diversion for the treatment of intracranial aneurysms has gained broad acceptance. Three flow-diverting stents are approved by the Food and Drug Administration for use in the United States. We sought to compare the outcomes and safety profiles between the three devices at our institution.

METHODS

A retrospective review of aneurysms treated with pipeline embolization device (PED), flow re-direction endoluminal device (FRED), and SURPASS was performed for aneurysms treated between 2018 and 2022 at our institution.

RESULTS

The study cohort consisted of 142 patients. Precisely, 86 aneurysms were treated with a pipeline, 33 aneurysms were treated with FRED, and 23 aneurysms were treated with SURPASS. The 1-year complete occlusion rates were 59.4%, 60%, and 65%, respectively (0.91). Linear regression models found that only adjunctive coiling predicted aneurysm occlusion at 6 months (p = 0.02), but this effect was lost at 1 year and beyond. There was no significant difference in acute thrombotic or acute hemorrhagic complications between the three cohorts. There was a higher rate of delayed hemorrhagic complications in the SURPASS cohort (10%) compared to the PED (1.3%) and FRED (0%) cohorts (p = 0.04). There was also a higher rate of in-stent stenosis in the SURPASS cohort (20%) compared to the PED (5%) and FRED (3.1%) cohorts (p < 0.01).

CONCLUSIONS

Treatment with PED, FRED, and SURPASS all resulted in similar complete occlusion rates at 6 months and 1 year. SURPASS was associated with higher in-stent stenosis as well as delayed hemorrhagic complications. Additional future studies evaluating the newest generation of flow-diverting stents with long-term follow-up will be necessary to make any definitive conclusions.

Surpass embolization of intracranial aneurysms: Perspective from a 2-year longitudinal follow-up study across high volume comprehensive stroke centers

BACKGROUND

Surpass Streamline (SS; Stryker^©) is an over-the-wire first-generation flow diverter (FD). There is a scarcity of data on real-world outcomes and complications of this FD.

METHODS

A retrospective review of consecutive cases between January 2019 and July 2021 at two high-volume comprehensive stroke centers, involving SS was conducted.

RESULTS

Fifty-five patients harbored 69 treated aneurysms, of which 96% were in the internal carotid petrous to terminus segments and 88% were <10 mm in size, and 12% measuring 10-24 mm. Raymond Roy Grade 1 occlusion was noted in 55 aneurysms (79.7%) at 1 year. Median follow-up duration was 26 months (mean = 26.06). Major complications were seen in eight patients (14.5%; 95% CI 6.5-26.7) and mortality attributable to SS stenting complications occurred in two (4.3%) patients. Four (7.2%) had ophthalmologic thromboembolic complications and two had (3.6%) ischemic complications. Procedural complications occurred in 10 patients (18.18%; 95% CI 9.1-30.9). Technical complications during procedure (n = 3, 5.3%) were: "confirmed" distal middle cerebral artery (MCA) guidewire perforation; "suspected" distal MCA guidewire perforation causing post-procedural subarachnoid hemorrhage and internal carotid artery dissection causing ischemic stroke. Seizures were seen in 5 (9.09%) and carotid-cavernous fistula in 1 (1.8%). Multivariate regression analysis showed technical challenges significantly predicted occurrence of major complications (p = 0.001; R²= 0.39, F(13,43) = 2.15, p = 0.029). Univariate analysis showed technical challenges significantly predicted ophthalmological complications (R²= 0.06, F(1,55) = 4.04, p = 0.049) and major complications (R²= 0.21, F(1,55) = 15.11, p = 0.0002).

CONCLUSION

Large-scale future registry should focus on national data regarding SS safety, technical challenges, and procedural complications. We present one of the longest follow-ups for SS in literature.

Technical considerations of endovascular management of true visceral artery aneurysms

BACKGROUND

True visceral artery aneurysms are potentially complex to treat but with advances in technology and increasing interventional radiology expertise over the past decade are now increasingly the domain of the interventional radiologist. BODY: The interventional approach is based on localization of the aneurysm and identification of the anatomical determinants to treat these lesions to prevent aneurysm rupture. Several different endovascular techniques are available and should be selected carefully, dependent on the aneurysm morphology. Standard endovascular treatment options include stent-graft placement and trans-arterial embolisation. Different strategies are divided into parent artery preservation and parent artery sacrifice techniques. Endovascular device innovations now include multilayer flow-diverting stents, double-layer micromesh stents, double-lumen balloons and microvascular plugs and are also associated with high rates of technical success.

CONCLUSION

Complex techniques such as stent-assisted coiling and balloon-remodeling techniques are useful techniques and require advanced embolisation skills and are further described.

And don't forget your anti in-stent stenosis pill! Commentary on 'Factors associated with in-stent stenosis after cerebral aneurysm embolization using a Pipeline embolization device' by Flores-Milan et al

In their INR study, Flores-Milan et al. present a retrospective single-centre study that aimed to investigate and determine some of the factors associated with in-stent stenosis (ISS) after intracranial aneurysm (IA) embolization using a commercially available flow diverter stent (FD). The retrospective analyses included ruptured and unruptured intracranial aneurysms treated with standalone flow diverter stent implantation or initial coil obliteration with the FD device placed subsequently two weeks after initial treatment. The article's methodology was carefully tailored to demystify the unknown pathophysiological mechanism behind the entity of interest called in-stent stenosis. Study outcomes also included angiographic evaluation of aneurysm occlusion thrombotic and hemorrhagic events. The authors reported excellent technical and clinical results altogether. The achieved angiographic occlusion rates resonate with the current obliteration results reported in the literature. Mortality and morbidity are congruent with previously published results and were 5.3% and 1.1%, respectively.

The DERIVO®2 Embolization Device in the treatment of ruptured and unruptured intracranial aneurysms: A multicenter analysis

BACKGROUND

Flow diverters are an increasingly used treatment option for intracranial aneurysms. A recent addition to the European market is the DERIVO®2 Embolization Device (DED2), promising improved radiopacity. We aimed to assess the safety and efficacy of the DED2 regarding angiographic and clinical outcomes in ruptured and unruptured cerebral aneurysms.

METHODS

We performed a multicenter trial at six interventional centers. Data were prospectively collected and all patients treated with the DED2 were included. The primary endpoint was angiographic aneurysm occlusion at 6 months as assessed by the O'Kelly Marotta (OKM) grading scale with a favorable outcome definition of OKM C + D. Clinical outcome was evaluated according to the modified Rankin scale (mRS).

RESULTS

Between August 2020 and July 2021, 37 patients were treated with the DED2 and were included in our analysis. Five patients presented with ruptured aneurysms. Median age was 60 years, 27 patients were female, and 10 male. Median mRS was 0 (range 0-4). Mean aneurysm size was 8.9 ± 7.1 mm with a mean neck size of 6.5 ± 6.1. The DED2 fully opened at deployment in all cases. Clinical follow-up was available for 30 patients (81%). Twenty-five (83%) had an mRS of 0 or 1. Three patients with ruptured aneurysms died during the follow-up period. No treatment-related major morbidity was observed. Follow-up imaging was available in 27 (90%) patients, with 23 patients (85%) showing satisfactory aneurysm occlusion OKM grade C-D.

CONCLUSION

In this small cohort, the DED2 provided safe and effective treatment of ruptured and unruptured intracranial aneurysms.

Clinical outcomes of pipeline embolization devices with shield technology for treating intracranial aneurysms

INTRODUCTION

As a common endovascular treatment for intracranial aneurysms, the pipeline embolization device (PED) is considered a standard treatment option, especially for large, giant, wide-necked, or dissecting aneurysms. A layer of phosphorylcholine biocompatible polymer added to the surface of the PED can substantially improve this technology. This PED with shield technology (pipeline shield) is relatively novel; its early technical success and safety have been reported. We conducted a systematic literature review with the aim of evaluating the efficacy and safety of the pipeline shield.

METHODS

We searched the PubMed, Embase, and Cochrane databases, following the preferred reporting items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines.

RESULTS

We selected five prospective and two retrospective studies for review. A total of 572 aneurysms were included; of these, 506 (88.5%) were unruptured. The antiplatelet regimens were heterogeneous. The rate of perioperative and postoperative complications was 11.1% [95% confidence interval (CI): 6.5-18.9%]. The adequate occlusion rate at 6 months was 73.9% (95% CI: 69.1-78.7%). The adequate occlusion rate of more than 12 months was 80.9% (95% CI: 75.1-86.1%). The mortality rate was 0.7% (95% CI: 0.2-1.5%). Subgroup analyses showed that aneurysm rupture status had no effect on aneurysm occlusion rate, patient morbidity, or mortality.

CONCLUSION

This review demonstrates the safety and efficacy of the pipeline shield for treating intracranial aneurysms. However, direct comparisons of the pipeline shield with other flow diverters are needed to better understand the relative safety and effectiveness of different devices.

North American multicenter experience with the Flow Redirection Endoluminal Device in the treatment of intracranial aneurysms

OBJECTIVE

Flow diverters have revolutionized the endovascular treatment of intracranial aneurysms. Here, the authors present the first large-scale North American multicenter experience using the Flow Redirection Endoluminal Device (FRED) in the treatment of cerebral aneurysms.

METHODS

Consecutive cerebral aneurysms treated with FRED at 7 North American centers between June 2020 and November 2021 were included. Data collected included patient demographic characteristics, aneurysm characteristics, periprocedural and long-term complications, modified Rankin Scale (mRS) scores, and radiological follow-up.

RESULTS

In total, 133 aneurysms in 116 patients were treated with 123 FRED deployment procedures and included in this study. One hundred twenty-six aneurysms (94.7%) were unruptured, 117 (88.0%) saccular, and 123 (92.5%) located in anterior circulation. The mean (range) aneurysm maximal width and neck width sizes were 7.2 (1.5-42.5) mm and 4.1 (1.0-15.1) mm, respectively. Successful FRED deployment was achieved in 122 procedures (99.2%). Adjunctive coiling was used in 4 procedures (3.3%). Radiological follow-up was available for 101 aneurysms at a median duration of 7.0 months. At last follow-up, complete occlusion was observed in 55.4% of patients, residual neck in 8.9%, and filling aneurysm in 35.6%; among cases with radiological follow-up duration > 10 months, these values were 21/43 (48.8%), 3/43 (7.0%), and 19/43 (44.2%), respectively. On multivariate regression analysis, age (OR 0.93, p = 0.001) and aneurysm neck size (OR 0.83, p = 0.048) were negatively correlated with odds of complete occlusion at latest follow-up. The retreatment rate was 6/124 (4.8%). The overall complication rate was 31/116 (26.7%). Parent vessel occlusion, covered branch occlusion, and in-stent stenosis were detected in 9/99 (9.1%), 6/63 (9.5%), and 15/99 (15.2%) cases, respectively. The FRED-related, symptomatic, thromboembolic, and hemorrhagic complication rates were 22.4%, 12.9%, 6.9%, and 0.9% respectively. The morbidity rate was 10/116 patients (8.6%). There was 1 death due to massive periprocedural internal carotid artery stroke, and 3.6% of the patients had an mRS score > 2 at the last follow-up (vs 0.9% at baseline).

CONCLUSIONS

As the first large-scale North American multicenter FRED experience, this study confirmed the ease of successful FRED deployment but suggested lower efficacy and a higher rate of complications than reported by previous European and South American studies on FRED and other flow-diverting devices. The authors recommend judicious use of this device until future studies can better elucidate the long-term outcomes of FRED treatment.

Preliminary Experience of the Surpass Streamline Flow Diverter for Large and Giant Unruptured Internal Carotid Artery Aneurysms

As of January 2021, the Surpass Streamline (SS) is the most recently approved flow diverter in Japan. A total of 28 Japanese patients, including 9 clinical trial patients, with 28 large or giant unruptured internal carotid artery (ICA) aneurysms, underwent SS embolization at Juntendo University Hospital. Procedural failure occurred in two patients due to the difficulty to navigate the device in the tortuous parent artery. Therefore, 26 patients with 26 aneurysms were available for clinical and anatomical assessments. Patients' mean age was 62.6 years (range 46-86), and 24 patients (92.3%) were female. Mean aneurysm size and neck width were 15.4 mm and 7.7 mm, respectively, with 20 saccular and 6 fusiform aneurysms. Seven aneurysms were symptomatic due to the aneurysmal mass effect. Twenty patients underwent a 6-month follow-up angiography to evaluate the degree of occlusion. Anatomical outcomes were 12 (60%) complete occlusion (CO), 4 (20%) residual neck (RN), and 4 (20%) residual aneurysm. Favorable aneurysm occlusion consisted of CO, and RN was achieved in 16 (80.0%). There were no significant device stenoses. Aneurysmal mass effect improved in one and was unchanged in eight patients. There were three device-related complications, namely, delayed aneurysm rupture, minor ischemic stroke, and device occlusion (11.5%). One patient with minor ischemic stroke fully recovered before 30 days, and our series showed 7.7% risk of major ipsilateral stroke and neurological death at 30 days. The SS embolization for large and giant unruptured ICA aneurysms offers satisfactory anatomical and clinical outcomes with a low risk of device-related complications.

Use of flow diverter device in basilar artery for aneurysm treatment: Case series and literature review

Background

Flow diverters (FDs) for the treatment of basilar artery (BA) aneurysms remain controversial. In this study, we report our initial experience of flow diversion for treatment of this pathology.

Methods

Consecutive patients with an aneurysm of the BA that was treated by implantation of the FD were included in our retrospective study. Procedural complications, aneurysm occlusion, and a functional outcome were evaluated. FD placement in BA for aneurysm treatment reported in the literature was also reviewed and summarized.

Results

Sixteen patients with 16 BA aneurysms were treated by FD implantation with (n = 8) or without (n = 8) adjunctive coiling. The Tubridge was used in 13 (81.3%) and Pipeline in 3 (18.8%) procedures. Average aneurysm size was 15.7 mm. Four aneurysms were located at the basilar apex, six at the basilar trunk, and six at the vertebrobasilar junction. Three patients experienced procedural complications (18.8%), including two ischemic strokes and one hydrocephalus, with resultant mortality in one case (6.3%). Median follow-up was 7.7 months and available for 15 aneurysms. Complete/near-complete occlusion was seen in 13 (86.7%) aneurysms.

Conclusion

In our initial experience, flow diversion is feasible and safe in the treatment of BA aneurysms with promising occlusion rates at mid-term follow-up. Larger cohort studies are required to validate these results.

Clinical Results of Flow Diverter Treatments for Cerebral Aneurysms under Local Anesthesia

Flow diverters (FD) have become the mainstay for the endovascular treatment of unruptured intracranial aneurysms (UIA). Most FD procedures are performed under general anesthesia, and the influence of local anesthesia (LA) on outcomes remains unknown. This study evaluated the results of FD placement under LA. Data of patients treated for FD under LA between August 2016 and January 2022 were analyzed retrospectively. A good outcome was defined as a modified Rankin scale score of 0–2. Major stroke, steno-occlusive events of FD, mortality, and satisfactory aneurysm occlusion were also evaluated. In total, 169 patients undertook 182 treatments (139 [82%) female, mean age 61 ± 11 years). The median maximum aneurysm size was 9.5 mm (interquartile range 6.1-14 mm). A flow re-directed endoluminal device and pipeline embolization device were used in 103 (57%) and 78 (43%) treatments. One patient (0.59%) experienced major stroke, and steno-occlusive events were observed in four patients (2.4%). A good outcome at 90 days was obtained in 164 patients (98%), and one patient died (0.59% mortality). During the median follow-up period of 345 days (interquartile range 176–366 days), satisfactory aneurysm occlusion was observed in 126 of 160 aneurysms (79%). Our results suggest that FD placement under LA is a safe and effective treatment for UIA.

Surpass Evolve Flow Diverter for the Treatment of Intracranial Aneurysm: A Systematic Review

PURPOSE

This systematic review aims to summarize the evidence investigating the effectiveness and safety of the Surpass Evolve-Flow Diverter (SE-FD) to treat brain aneurysms.

METHOD

We searched MEDLINE, EMBASE, CINAHL, Web of Science, and Cochrane Library from January 2019 to 29 March 2022. Terms related to the "intracranial aneurysm" and "surpass evolve flow diverter" concepts were used to search the databases; Medical Subject Headings (MeSH) and reference hand search were also utilized.

RESULTS

The searches primarily identified 1586 documents. A total of five studies (four case series and one cohort) were included in this review. In the included studies, 192 (74 male and 118 females) patients with 198 aneurysms were involved. In total, 153 SE-FDs were used to treat 145 aneurysms. Complete occlusion was achieved in 69/145 (48%) cases and near-complete occlusion in 24/145 (17%) cases from aneurysms treated with SE-FD. Reported postoperative complications included stent thrombosis (n = 4 patients), hemorrhage (n = 5 patients), ischemia (n = 9 patients), and neurological complications (n = 12 patients). In total, four deaths were reported with only one related to the SE-FD procedure.

CONCLUSION

The results of this review are based on observational data, due to the absence of clinical trials. The findings of the included studies suggest that the effectiveness of the SE-FD procedure is lower than previous FDs but the safety is similar. The included studies also suggested that SE-FD has navigability and resistance to twisting, which makes the procedure an easier method to treat aneurysms that are proximal and distal to the circle of Willis deployment. This review highlights the urgency to conduct clinical trials to confirm these suggestions.

Dataset on flow diversion procedures performed with the Pipeline Embolization Device, Pipeline Flex, and Surpass Streamline for intracranial aneurysms

Flow diversion is an evolving endovascular modality for treating intracranial aneurysms. Although rare, serious adverse events following flow diversion may include ischemic stroke, intracranial hemorrhage, or delayed rupture of the treated aneurysm. This dataset describes 141 flow diversion procedures performed with the Pipeline Embolization Device, Pipeline Flex, or Surpass Streamline on 126 subjects with intracranial aneurysms [1]. The retrospective data were collected from electronic medical records at two large tertiary centers. Baseline patient data included age, sex, and medical comorbidities. The dataset also describes aneurysm characteristics including laterality, anatomic location, morphology, dome height, and neck width. In addition, digital subtraction images showing the internal carotid artery tortuosity were included for aneurysms in the anterior cerebral circulation [2]. Procedural data include case duration, radiation exposure, number of flow diverters deployed, and complications encountered during deployment. In addition, data related to the duration of hospitalization and postoperative adverse events are included. Finally, time to follow up and rates of total aneurysm obliteration at first and second postoperative visits are included. This data is propensity score matching are included. This data is presented as a starting point for future prospective comparisons in the safety and efficacy of flow diverters as more devices become approved and commercially available.

Pipeline Embolization Device and Pipeline Flex Versus Surpass Streamline Flow Diversion in Intracranial Aneurysms: A Retrospective Propensity Score-Matched Study

OBJECTIVE

To compare safety and efficacy profiles in aneurysms treated with Pipeline Embolization Device or Pipeline Flex versus Surpass Streamline flow diverters (FDs).

METHODS

Patients who underwent flow diversion for aneurysm treatment at 2 centers were included. Covariates comprised patient demographics, comorbidities, and aneurysm characteristics. Metrics included number of devices, adjuvant device use, case duration, and radiation exposure. Outcomes included periprocedural complications and radiographic results at follow-up. Propensity score-matched pairs were generated using demographic and aneurysm characteristics to verify the outcomes in equally sized groups.

RESULTS

The majority of 141 flow diversion procedures performed on 126 patients were in the anterior circulation (96%) and unruptured (93%). Operators experienced more complications placing Surpass FDs compared with Pipelines (18.2% vs. 3.1%, P = 0.005) but used fewer Surpass devices per case (1 device in all Surpass cases and range for Pipeline cases 1-7; P < 0.001). Ballooning was more frequent for Surpass (29.5% vs. 2.1%, P < 0.001). There were no differences in mortality (2.1% vs. 0, P = 1.00), intracranial hemorrhage (3.1% vs. 0, P = 0.551), or stroke (4.2% vs. 6.8%, P = 0.680). Rates of aneurysm obliteration at follow-up were similar. Propensity-matched pairs had no differences in FD deployment complications or perioperative events, yet the significant differences remained for adjuvant balloon use and number of FDs deployed.

CONCLUSIONS

While the devices demonstrated similar safety and efficacy profiles, deployment of the Surpass Streamline was more technically challenging than Pipeline Embolization Device or Pipeline Flex. Prospective cohort studies are needed to corroborate these findings.

A Single Flow Re-direction Endoluminal Device for the Treatment of Large and Giant Anterior Circulation Intracranial Aneurysms

PURPOSE

The purpose of this study was to report the author's experiences in treating large (10-25 mm) and giant (>25 mm) intracranial aneurysms (IAs) using a single Flow Re-direction Endoluminal Device (FRED) without assistant coiling, with a focus on procedure-related complications.

MATERIALS AND METHODS

A total of 33 patients who were treated with FRED between January 2018 and July 2020 were retrospectively reviewed. The timing of procedure-related complications was chronologically categorized as acute (within 7 days), subacute (8 to 21 days), and delayed (after 21 days) periods. Follow-up angiography was performed at 2 to 27 months (mean 9.7 months), and clinical follow-up was performed at 1 to 31 months (mean 14.1 months) in all patients.

RESULTS

Six (18.2%) patients experienced procedure-related complications, including 2 (6.1%) in acute period, 1 (3.0%) in subacute period, and 3 (9.1%) in delayed period. Thromboembolic complications occurred in 5 (15.2%) patients and hemorrhagic complications in 1 (3.0%). Permanent morbidity and mortality rates were 3.0% each. Non-internal carotid artery (ICA) location of IAs (odds ratio 6.532; 95% confidence interval, 1.335-17.816; p=0.034) was the only independent risk factor for procedure-related complications on multivariate logistic regression analysis.

CONCLUSION

The procedure-related complication rate was 18.2% in this study. Procedure-related complications might increase when treating large and giant IAs located on a non-ICA, especially on the middle cerebral artery. Therefore, it may be suggested that neurointerventionists and endovascular neurosurgeons should pay attention to the location of IAs when treating large and giant IAs with a single FRED.

Use of Surpass Streamline Flow Diverter for the Endovascular Treatment of Craniocervical Aneurysms: a Single-Institution Experience

INTRODUCTION

Flow diversion has revolutionized endovascular treatment for cerebral aneurysms. Surpass Streamline flow-diverter (SSFD) has shown promise for expanding flow diversion device options for aneurysm treatment. The SSFD differs from earlier stents by maintaining high porosity with increased pore density to ensure appropriate flow disruption. Given the delivery system's increased dimension options, and potential greater flow diverting properties, the SSFD is poised to extend the anatomic/pathologic reaches of flow diversion therapy.

METHODS

Data pertaining to SSFD-treated aneurysms were gathered retrospectively from 2019 to 2020. Collected information included aneurysm location, size, symptoms, complications, and occlusions rates at follow-up. Size was categorized as small (<10 mm), large (10-25 mm), and giant (>25 mm) according to SCENT trial criteria. Aneurysm occlusion on follow-up imaging was characterized by SMART grading with adequate occlusion defined as grades 3 and 4. Imaging was performed at time of treatment, six-month, and one-year follow-up.

RESULTS

42 SSFD-treated aneurysms were treated throughout the cerebrovascular system; 3 cervical, 4 posterior, and 35 intracranial anterior circulation. Complete occlusion rates at six months and one year were 48% and 57% with adequate occlusion achieved in 89.6% and 85.7% respectively. Rates of complete occlusion were higher for small aneurysms (69%) compared to large aneurysms (38%).

CONCLUSIONS

Our data suggests comparable complete occlusion rates compared to the SCENT trial (66.1% vs 57% in our center) and adequate occlusion rates. Similar occlusion rates to prior studies despite broadened inclusion criteria/diversity of aneurysms treated demonstrates favorable generalizability of flow-diverting technology to a wide array of aneurysmal pathology.

A systematic review and meta-analysis of the Derivo Embolization Device: a novel surface-modified flow diverter for intracranial aneurysm treatment

BACKGROUND

Surface-modified flow diverters (FDs) designed to reduce thrombogenicity represent the next frontier for intracranial aneurysm treatment. The Derivo Embolization Device (DED) is a novel FD with titanium oxide and titanium oxynitride finishing of the struts. We performed a systematic review of pertinent literature, aiming to evaluate the device's effectiveness and safety.

METHODS

A literature search of PubMed, Embase, and MEDLINE was conducted following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines.

RESULTS

Five studies comprising 481 aneurysms were included. These studies were conducted in Turkey, Brazil, Germany, Poland, and Italy; two were prospective and three were retrospective. Twenty-six aneurysms (5.4%) were ruptured. The antiplatelet regimens were heterogeneous, but dual antiplatelet therapy was administered preprocedurally in all studies and maintained for 3-12 months before a switch to single antiplatelet therapy. The rate of periprocedural ischemic and hemorrhagic complications was 4.9% (95% CI 2.9% to 7%). Adjunctive coiling was used in 25.6% (95% CI 11.4% to 39.8%) of aneurysms. The complete angiographic occlusion rate was 81.4% (95% CI 71.3% to 91.5%), mortality rate was 2.1% (95% CI 0.4% to 3.9%), with follow-up ranging from 9 to 18 months. Delayed aneurysm rupture was reported in one patient.

CONCLUSIONS

The DED has been increasingly used in other countries. We identified low rates of periprocedural complications and mortality and a high rate of complete occlusion.

Outcomes following aneurysmal coil embolization with intentionally shortened low-profile visible intraluminal support stent deployment

PURPOSE

Among all stents available for neuroendovascular therapy, the low-profile visible intraluminal support stent bears the highest metal coverage ratio. We deployed a low-profile visible intraluminal support stent with a delivery wire or/and microcatheter system push action to shorten the low-profile visible intraluminal support stent and thus achieve a flow diversion effect. We report our single-institution experience with the use of low-profile visible intraluminal support stents for intentionally shortened deployment (shortening group) and non-shortened deployment (non-shortening group) for unruptured intracranial aneurysms.

METHODS

We retrospectively reviewed the medical records of 130 patients with 131 intracranial aneurysms who were treated with low-profile visible intraluminal support stent-assisted coil embolization from February 2016-January 2019. All perioperative complications were noted. Every 6 months, we re-examined the patients with cerebral angiography or magnetic resonance angiography. The outcomes of aneurysm occlusion were evaluated by the modified Raymond-Roy occlusion classification. We used the finite element method and computational fluid dynamics to investigate the hemodynamics after shortened low-profile visible intraluminal support stent deployment.

RESULTS

Immediately after treatment, the modified Raymond-Roy occlusion classification was significantly better in the shortening group than in the non-shortening group (p<0.05). The latest angiographic outcomes showed the same tendency. Hemodynamic analysis by computational fluid dynamics suggested an adequate flow diversion effect with the use of our intentional shortening method.

CONCLUSIONS

Stent-assisted coil embolization using this technique showed good results of a high complete occlusion rate and low complication rate. These findings suggest that shortened low-profile visible intraluminal support stent deployment yields a flow diversion effect and may lead to early intra-aneurysmal thrombus formation.

Diversion-p64: results from an international, prospective, multicenter, single-arm post-market study to assess the safety and effectiveness of the p64 flow modulation device

BACKGROUND

The use of flow diversion to treat intracranial aneurysms has increased in recent years.

OBJECTIVE

To assess the safety and angiographic efficacy of the p64 flow modulation device.

METHODS

Diversion-p64 is an international, prospective, multicenter, single-arm, study conducted at 26 centers. The p64 flow modulation device was used to treat anterior circulation aneurysms between December 2015 and January 2019. The primary safety endpoint was the incidence of major stroke or neurologic death at 3-6 months, with the primary efficacy endpoint being complete aneurysm occlusion (Raymond-Roy Occlusion Classification 1) on follow-up angiography.

RESULTS

A total of 420 patients met the eligibility criteria and underwent treatment with the p64 flow modulation device (mean age 55±12.0 years, 86.2% female). Mean aneurysm dome width was 6.99±5.28 mm and neck width 4.47±2.28 mm. Mean number of devices implanted per patient was 1.06±0.47, with adjunctive coiling performed in 14.0% of the cases. At the second angiographic follow-up (mean 375±73 days), available for 343 patients (81.7%), complete aneurysm occlusion was seen in 287 (83.7%) patients. Safety data were available for 413 patients (98.3%) at the first follow-up (mean 145±43 days) with a composite morbidity/mortality rate of 2.42% (n=10).

CONCLUSIONS

Diversion-p64 is the largest prospective study using the p64 flow modulation device. The results of this study demonstrate that the device has a high efficacy and carries a low rate of mortality and permanent morbidity.

Repeat Flow Diversion for Cerebral Aneurysms Failing Prior Flow Diversion: Safety and Feasibility From Multicenter Experience

BACKGROUND AND PURPOSE

Aneurysmal persistence after flow diversion (FD) occurs in 5% to 25% of aneurysms, which may necessitate retreatment. There are limited data on safety/efficacy of repeat FD-a frequently utilized strategy in such cases.

METHODS

A series of consecutive patients undergoing FD retreatment from 15 centers were reviewed (2011-2019), with inclusion criteria of repeat FD for the same aneurysm at least 6 months after initial treatment, with minimum of 6 months post-retreatment imaging. The primary outcome was aneurysmal occlusion, and secondary outcome was safety. A multivariable logistic regression model was constructed to identify predictors of incomplete occlusion (90%-99% and <90% occlusion) versus complete occlusion (100%) after retreatment.

RESULTS

Ninety-five patients (median age, 57 years; 81% women) harboring 95 aneurysms underwent 198 treatment procedures. Majority of aneurysms were unruptured (87.4%), saccular (74.7%), and located in the internal carotid artery (79%; median size, 9 mm). Median elapsed time between the first and second treatment was 12.2 months. Last available follow-up was at median 12.8 months after retreatment, and median 30.6 months after the initial treatment, showing complete occlusion in 46.2% and near-complete occlusion (90%-99%) in 20.4% of aneurysms. There was no difference in ischemic complications following initial treatment and retreatment (4.2% versus 4.2%; P>0.99). On multivariable regression, fusiform morphology had higher nonocclusion odds after retreatment (odds ratio [OR], 7.2 [95% CI, 1.97-20.8]). Family history of aneurysms was associated with lower odds of nonocclusion (OR, 0.18 [95% CI, 0.04-0.78]). Likewise, positive smoking history was associated with lower odds of nonocclusion (OR, 0.29 [95% CI, 0.1-0.86]). History of hypertension trended toward incomplete occlusion (OR, 3.10 [95% CI, 0.98-6.3]), similar to incorporated branch into aneurysms (OR, 2.78 [95% CI, 0.98-6.8]).

CONCLUSIONS

Repeat FD for persistent aneurysms carries a reasonable success/safety profile. Satisfactory occlusion (100% and 90%-99% occlusion) was encountered in two-thirds of patients, with similar complications between the initial and subsequent retreatments. Fusiform morphology was the strongest predictor of retreatment failure.

Efficacy and safety of flow diverters in posterior circulation aneurysms and comparison with their efficacy in anterior circulation aneurysms: A systematic review and meta-analysis

PURPOSE

We aimed to assess the efficacy and safety of flow-diverter stents (FDs) in the management of posterior circulation cerebral aneurysms and compare FD efficacy between anterior and posterior circulation aneurysms.

METHODS

We searched the PubMed, Scopus, Cochrane, and Web of Science databases for relevant studies through March 2020. Studies assessing FDs for posterior circulation aneurysms that included ≥20 treated aneurysms were included. Moreover, the studies compared FD efficacy between anterior and posterior circulation aneurysms were included. Data regarding angiographic aneurysmal occlusion, procedural complications, mortality, and morbidity were extracted and pooled in a random-effects meta-analysis model.

RESULTS

Fourteen studies with a total of 659 patients and 676 posterior circulation aneurysms were included. The pooled rate of aneurysmal occlusion at long-term angiographic follow-up was 78% [95% confidence interval (CI), 71-85]. The pooled rates of intraparenchymal hemorrhage, ischemia, and procedure-related mortality and neurological morbidity were 2%, 8%, 7%, and 6%, respectively. Complete occlusion occurred in 82.4% of the posterior circulation aneurysm subgroup and 77.5% of the anterior circulation aneurysm subgroup. The difference was not significant (relative risk 1.01; 95% CI, 0.86-1.19; p = 0.91). Regression analysis showed that elderly patients and females had higher morbidity.

CONCLUSION

Posterior circulation aneurysms can be effectively treated with FDs with comparable occlusion rates to those in anterior circulation aneurysms. However, periprocedural complications are not negligible.

Early clinical experience of using the Surpass Evolve flow diverter in the treatment of intracranial aneurysms

PURPOSE

Here, we presented our early experience with flow diversion procedures using the Surpass Evolve flow diverter (SE, Stryker) and reported the feasibility and safety profile compared to those of a control group treated with other types of flow diverters.

METHODS

We included 31 and 53 consecutive flow diversion procedures performed using the SE and other commercial flow diverters, respectively, to treat intracranial aneurysms at our institution. We used two commercial flow diversion systems in the comparison group: the pipeline embolization device and Surpass Streamline.

RESULTS

In the SE group, technical failures occurred in three (9.7%) cases, due to either incomplete wall apposition (n = 1, 3.2%) or stent migration (n = 2, 6.5%). Major complications occurred in four (12.9%) cases: delayed rupture of the target aneurysm (n = 1, 3.2%), major ischemic stroke (n = 1, 3.2%), sudden death from an unidentified cause (n = 1, 3.2%), and parent artery occlusion with stent thrombosis (n = 1, 3.2%). Balloon angioplasty was performed in eight (25.8%) cases. On post-procedure MRI, a DWI-positive lesion was detected in three (9.7%) cases. After multivariate adjustment, the SE group was independently associated with less procedural time of ≥ 90 min (adjusted OR, 0.09; 95% CI, 0.03-0.29; p < 0.001), balloon angioplasty (adjusted OR, 0.22; 95% CI, 0.07-0.75; p = 0.015), and DWI-positive lesions (adjusted OR, 0.04; 95% CI, 0.01-0.19; p < 0.001).

CONCLUSION

The SE is safe and easy to deploy.

Treatment of Intracranial Aneurysms Using the New Silk Vista Flow Diverter: Safety Outcomes at Short-Term Follow-Up

Background: Flow diverters are widely used as the first endovascular treatment option for complex brain aneurysms due to their high percentage of occlusion and low morbi-mortality. The Silk Vista device is a new generation of flow diverters designed to facilitate full visibility, improve apposition to the vessel wall, and enhance navigability. Indeed, its greatest advantage is that it enables the easier navigation of stents between 3.5 and 4.75 mm through a 0.021 microcatheter. The objective of this study was to evaluate the safety and effectiveness of Silk Vista systems for treating cerebral aneurysms.

Methods: This prospective observational study included 25 consecutive patients with 27 wide-necked unruptured aneurysms treated with SILK Vista who were retrospectively analyzed for safety and efficacy.

Results: Endovascular treatment was successfully performed in all patients. The final morbidity and mortality rates were both 0.0%. Short-term (3–5 months) angiographic follow-up revealed 21 complete occlusions and 6 near-complete occlusions. No significant parent artery stenosis was observed.

Conclusions: This report demonstrates the efficacy of Silk Vista in treating brain aneurysms, although longer experiences should be carried out to confirm our results.

Endovascular Treatment of Intracranial Aneurysms

Traditionally, surgical clipping was the only available treatment modality for intracranial aneurysms. However, in the last few decades, the endovascular therapy of intracranial aneurysms (IAs) has seen a tremendous evolution and development. From coiling to flow diversion and flow disruptor devices, endovascular treatment modalities have increased in number and received broader indications throughout the years. In this review article, the treatment modalities for the endovascular management of IAs are presented, emphasizing newer devices and technologies.

Treatment of intracranial aneurysms using the new Surpass Evolve flow diverter: Safety outcomes and six-month imaging follow-up

BACKGROUND AND PURPOSE

Several studies have reported good long-term results in the occlusion of intracranial aneurysms with flow diverter treatment. The aim of this study was to report the safety and six-month follow-up outcomes using the new Surpass Evolve flow diverter in the treatment of intracranial aneurysms.

MATERIALS AND METHODS

Consecutive patients with intracranial aneurysm treated with Surpass Evolve flow diverter in two high-volume neurovascular centers between May 2019 and January 2020 were retrospectively reviewed. Procedure-related complications, aneurysm occlusion (O'Kelly-Marotta grading scale), and clinical outcomes were assessed.

RESULTS

Twenty-nine patients with 30 aneurysms were included in the study. Favorable aneurysm occlusion (O'Kelly Marotta grading scale C-D) at six-month follow-up was achieved in 21/27 (78%) aneurysms. No clinical procedure related thromboembolic complications were encountered. Twenty-three out of 24 patients with unruptured aneurysms treated with Surpass Evolve remained clinically intact at clinical follow-up. There was one fatal hemorrhagic procedure-related complication (3%). In five patients with ruptured aneurysms, no early or late rebleeds occurred from the aneurysms.

CONCLUSIONS

Surpass Evolve FD worked technically well with no intraprocedural thromboembolic complications and occlusion rates comparable to other FDs.

Endovascular Treatment of Anterior Circulation Aneurysms With the p64 Flow Modulation Device: Mid- and Long-Term Results in 617 Aneurysms From a Single Center

BACKGROUND

Flow diverters have become an important tool in the treatment of intracranial aneurysms, especially when dealing with difficult-to-treat or complex aneurysms. The p64 is the only fully resheathable and mechanically detachable flow diverter available for clinical use.

OBJECTIVE

To evaluate the safety and effectiveness of p64 for the treatment of intracranial saccular unruptured aneurysms arising from the anterior circulation over a long-term follow-up period.

METHODS

We retrospectively reviewed our prospectively maintained database to identify all patients who underwent treatment for an intracranial saccular (unruptured or beyond the acute hemorrhage phase) aneurysm arising from the anterior circulation with ≥1 p64 between December 2011 and December 2019. Fusiform aneurysms and dissections were excluded. Aneurysms with prior or concomitant saccular treatment (eg, coiling and clipping) were included. Aneurysms with parent vessel implants other than p64 were excluded. Anatomic features, intraprocedural complications, clinical outcome, as well as clinical and angiographic follow-ups were all recorded.

RESULTS

In total, 530 patients (388 females; median age 55.9 yr) with 617 intracranial aneurysms met the inclusion criteria. The average number of devices used per aneurysm was 1.1 (range 1-3). Mean aneurysm dome size was 4.8 mm (range 1-27 mm). Treatment-related morbimortality was 2.4%. Early, mid-term, and long-term angiographic follow-up showed complete or near-complete aneurysm occlusion in 76.8%, 89.7%, and 94.5%, respectively.

CONCLUSION

Treatment of intracranial saccular unruptured aneurysms of the anterior circulation using p64 is a safe and effective treatment option with high rate of occlusion at long-term follow-up and low morbimortality.

Whether Intracranial Aneurysm Could Be Well Treated by Flow Diversion: A Comprehensive Meta-Analysis of Large-Sample Studies including Anterior and Posterior Circulation

BACKGROUND

Flow diversion (FD) has become a widely adopted treatment method for intracranial aneurysms in the clinic, but a comprehensive meta-analysis of large-sample studies including anterior and posterior circulation is still lacking.

METHODS

The PubMed, Embase, Web of Science, and Cochrane databases were searched between January 1, 2008, and December 1, 2019. A random-effect model was used to calculate the efficacy and safety data as well as 95% confidence intervals (CIs).

RESULTS

The pooled sample size of all included studies was 6695 patients; the mean age was 55.5 years old, with a total of 7406 aneurysms. For efficacy, the complete occlusion rate in angiographic follow-up (AFU) at 6 months was 78% (95% CI, 0.77, 0.80), and the AFU rate at 6-12 months was 90% (95% CI, 0.88, 0.92). For safety, the hemorrhagic event rate was 2%, the ischemic event rate was 5%, and the mortality rate was 3%.

CONCLUSION

FD is an effective and safe treatment for intracranial aneurysm with high complete occlusion rate and acceptable complication rate.

Long-term clinical and angiographic follow-up results of the dual-layer flow diverter device (FRED) for the treatment of intracranial aneurysms in a multicenter study

PURPOSE

Our aim was to determine the long-term safety and efficacy of the Flow Re-Direction Endoluminal Device (FRED) in this multicenter study with prospective design.

MATERIALS-METHOD

This study included 136 consecutive patients with 155 aneurysms treated between March 2013 and June 2016 in 10 centers. Twenty-two (16.2%) patients presented with rupture of the index aneurysm. Large/giant aneurysms comprised 1/3 of the cohort. Adjuvant coil use during the treatment was 15.5%. The effectiveness measure in the study was the percentage of aneurysms with stable occlusion at follow-up.

RESULTS

Vascular imaging follow-up was performed at least once in 131/136 (96.3%) patients with 148/155 (95.5%) aneurysms up to 75 months (mean: 37.3 months; median: 36 months according to latest follow-up), and 102/155(65.8%) aneurysms in 90/136 (66.2%) patients had ≥ 24-month control. According to the latest controls, the overall stable occlusion rate was 91.9% (95% CI, 87.5 to 96.3%). Three out of 148 aneurysms with follow-up were retreated (2%, 95% CI 0.0 to 4.3%). Adverse events were noted in 19/136 (14%, 95% CI, 9 to 21%) patients with a morbidity of 1.5% (95% CI, 0.0 to 3.5%). Mortality was 1/136 (0.7%, 95% CI, 0.02 to 2.2%) and was unrelated to aneurysm treatment. In-stent stenosis (ISS) was detected in 10/131 of the patients with follow-up (7.6%, 95% CI; 3.1 to 12.2%), only one being symptomatic. No adverse events have occurred in any of the patients with follow-up after 24 months, except the one resulting from ISS.

CONCLUSION

In the treatment of cerebral aneurysms which were candidates for flow diversion technique, this study showed long-term efficacy of FRED with good safety and occlusion rates.

Intracranial aneurysms managed by parent artery reconstruction using Tubridge: Study protocol for a prospective, multicenter, post-market clinical trial

BACKGROUND

As a new endovascular reconstruction technique, flow diverter (FD) shows excellent efficacy and safety for treatment of intracranial aneurysms. In a previous multicenter, randomized, controlled, pre-market study, Tubridge FD showed remarkably higher complete occlusion rate compared with traditional stent-assisted coiling. However, a nonsignificant higher complication rate in the Tubridge group was noted. Considering the learning curve, the safety, and long-term outcomes of Tubridge FD should be verified in new prospective, real world, multicenter, post-market trials.

METHODS

This study is a prospective, multicenter, single-arm, post-market clinical trial that evaluates the safety and efficacy of Tubridge in the treatment of patients with intracranial aneurysms by reconstructing parent artery. We expect 200 participants who meet the inclusion and exclusion criteria to be included. Clinical information and angiographic results (Raymond-Roy grading scale, RRGS) will be recorded objectively. The primary endpoint will be the complete occlusion rate of the target aneurysm (RRGS 1) at 12-month follow-up. Secondary endpoints will include the adequate occlusion rate (RRGS 1 & 2) and the rate of major in-stent stenosis (>50%) at 12-month follow-up, technique success rate, changes of modified Rankin Scale before and after the procedure, the rate of aneurysm related disability, neurological mortality, and all-cause mortality within follow-up period.

DISCUSSION

This post-market, prospective trial may offer more information on the safety and long-term outcomes of Tubridge FD. When the study is complete, the results may provide us a new strategy for the treatment of intracranial aneurysms.Trial registration: WHO-Chinese Clinical Trial Registry: ChiCTR2000032282.

Overview of Different Flow Diverters and Flow Dynamics

Over the past decade, flow diverter technology for endocranial aneurysms has seen rapid evolution, with the development of new devices quickly outpacing the clinical evidence base. However, flow diversion has not yet been directly compared to surgical aneurysm clipping or other endovascular procedures. The oldest and most well-studied device is the Pipeline Embolization Device (PED; Medtronic), recently transitioned to the Pipeline Flex (Medtronic), which still has sparse data regarding outcomes. To date, other flow diverting devices have not been shown to outperform the PED, although information comes primarily from retrospective studies with short follow-up, which are not always comparable. Because of this lack of high-quality outcome data, no reliable recommendations can be made for choosing among flow diversion devices yet. Moreover, the decision to proceed with flow diversion should be individualized to each patient. In this work, we wish to provide a comprehensive overview of the technical specifications of all flow diverter devices currently available, accompanied by a succinct description of the evidence base surrounding each device.

Treatment of Anterior Circulation Aneurysms in the Internal Carotid Artery With Flow Diverters

Several studies have shown the efficacy and feasibility of flow diversion for the endovascular treatment of wide-necked and otherwise anatomically challenging intracranial aneurysms (IA). Technological advances have led to successful long-term occlusion rates and a safety profile for flow-diverter stents that parallels other endovascular and open surgical options for these lesions. With growing indications for use of the Pipeline Embolization Device (PED, Medtronic, Dublin, Ireland) to include IAs up to the internal carotid artery (ICA) terminus, understanding the nuances of this technology is increasingly relevant. Furthermore, there is a growing body of literature on the use of flow diversion to treat distal (up to A2, M2, and P2), ruptured, and posterior circulation aneurysms, although these applications are "off-label" at present. In this manuscript, we discuss the expanding role of flow diversion in the ICA and compare this technique with other endovascular options for the treatment of ICA IAs. We also discuss technical nuances of the deployment of flow diverters for the treatment of challenging lesions and in difficult and tortuous anatomy.

The Exchange-Free Technique: A Novel Technique for Enhancing Surpass Flow Diverter Placement

Background:

Following flow diverter placement, approximately 20% of intracranial aneurysms remain as residual aneurysms at 1 year. Device malapposition is a cause of residual aneurysms after flow diversion. We present a new and straightforward technique (exchange-free technique [EFT]) to enhance apposition of the surpass flow diverter (SFD), the only over-the-wire flow diverter currently available.

Materials and Methods:

We deployed laser-cut mini stents through the inner deployment catheter of the SFD. This maneuver was performed simply by withdrawing the micro-guidewire from its lumen and replacing it with a mini-stent (stents deliverable through microcatheters with inner diameter of 0.0165 inches), without a need to re-cross the deployed SFD or an exchange maneuver. All aneurysms in which this technique was utilized were retrospectively reviewed.

Results:

Twenty-eight patients (20 females) with 30 treated aneurysms were identified. The mean aneurysm diameter was 10.2 ± 6.6 mm. Technical success rate was 96.6% (29/30 aneurysms). There was no mortality or permanent morbidity related to the procedures. Except for the patient treated for an iatrogenic, surgery-related internal carotid artery pseudoaneurysm who died secondary to consequences of multiple surgeries, no cases of mortality or permanent morbidity were noted. Complete aneurysm occlusion rates were 78.2%, 82.1%, and 95.2% at 0–3, 3–6, and 9–12 months, respectively. None of the patients were re-treated.

Conclusion:

EFT is a simple and fast technique which was not associated with adverse effects in our series. The higher aneurysm obliteration rate obtained with EFT is probably the result of better wall apposition of the SFD.

Review of current intracranial aneurysm flow diversion technology and clinical use

Endovascular treatment of intracranial aneurysms (IAs) has evolved considerably over the past decades. The technological advances have been driven by the experience that coils fail to completely exclude all IAs from the blood circulation, the need to treat the diseased parent vessel segment leading to the aneurysm formation, and expansion of endovascular therapy to treat more complex IAs. Stents were initially developed to support the placement of coils inside wide neck aneurysms. However, early work on stent-like tubular braided structure led to a more sophisticated construct that then later was coined as a flow diverter (FD) and found its way into clinical application. Although FDs were initially used to treat wide-neck large and giant internal carotid artery aneurysms only amenable to surgical trap with or without a bypass or endovascular vessel sacrifice, its use in other types of IAs and cerebrovascular pathology promptly followed. Lately, we have witnessed an explosion in the application of FDs and subsequently their modifications leading to their ubiquitous use in endovascular therapy. In this review we aim to compile the available FD technology, evaluate the devices' peculiarities from the authors' perspective, and analyze the current literature to support initial and expanded indications, recognizing that this may be outdated soon.

Branch vessel occlusion in aneurysm treatment with flow diverter stent

Flow diverter placement for treatment of intracranial aneurysms gained growing consensus in the past years. A major concern among professionals is the side branch coverage which leads in some cases to vessel occlusion. However, the lost vessel patency only infrequently is accompanied by a new onset of neurological deficits secondary to ischaemic lesions. A retrospective analysis of all patients treated with flow diversion at our hospital was aimed to better understand this phenomenon in order to formulate a hypothesis about the causes. We concluded that vessel occlusion occurs due to a reduced blood pressure gradient in those vessels with a strong collateral or anastomotic vascularization that refurnishes the same distal vascular territories. Indeed, we detected no new brain infarction since blood flow was always guaranteed.

Derivo embolization device in the treatment of unruptured intracranial aneurysms: a prospective multicenter study

Background

Flow diverters (FD) are used regularly for the endovascular treatment of unruptured intracranial aneurysms. We aimed to assess the safety and effectiveness of the Derivo embolization device (DED) with respect to long-term clinical and angiographic outcomes.

Methods

A prospective multicenter trial was conducted at 12 centers. Patients presenting with modified Rankin Score (mRS) of 0–1, treated for unruptured intracranial aneurysms with DED were eligible. Primary endpoint was the mRS assessed at 18 months with major morbidity defined as mRS 3–5. Satisfactory angiographic occlusion was defined as 3+4 on the Kamran scale.

Results

Between July 2014 and February 2018, 119 patients were enrolled. Twenty-three patients were excluded. Ninety-six patients, 71 (74%) female, mean age 54±12.0 years, were included in the analysis. Mean aneurysm size was 14.2±16.9 mm. The mean number of devices implanted per patient was 1.2 (range 1–3). Clinical follow-up at 18 months was available in 90 (94%) patients, resulting in a mean follow-up period of 14.8±5.2 months. At last available follow-up of 96 enrolled patients, 91 (95%) remained mRS 0–1. The major morbidity rate (mRS 3–5) was 3.1% (3/96), major stroke rate was 4.2% (4/96), and mortality was 0%. Follow-up angiographies were available in 89 (93%) patients at a median of 12.4±5.84 months with a core laboratory adjudicated satisfactory aneurysm occlusion in 89% (79/89).

Conclusion

Our results suggest that DED is a safe and effective treatment for unruptured aneurysms with high rates of satisfactory occlusion and comparably low rates of permanent neurological morbidity and mortality.

Trial registration

DRKS00006103

Endovascular reconstruction of iatrogenic internal carotid artery injury following endonasal surgery: a systematic review

The objective of this study is to provide an update on endovascular treatments for iatrogenic internal carotid artery (ICA) injuries following endonasal surgery. A systematic review of the literature was performed by using Medline, Cochrane library, and Scopus from 1999 to 2019. We used a combination of the MeSH terms "internal carotid artery," "iatrogenic disease," and "endovascular procedure." Twenty-six articles including 46 patients were identified for in this systematic review. The mean age of the patients was 49 years (CI: ± 4.2). The most common site of ICA injury was in cavernous segment (18 patients; 39%). The most common type of iatrogenic ICA injury was a traumatic pseudoaneurysm documented in 28 patients (60%). Endoluminal reconstruction was performed using covered stents in 28 patients, the Pipeline embolization device (PED) in 13 patients, the Surpass flow diverter device in three, the SILK flow diverter in one, and one case was treated using a combined approach of a covered stent and a PED. Flow diversion and covered stents resulted in a good clinical outcome in 94% and 89% of patients, respectively. This difference did not reach statistical significance (p = 1.0). Even though this systematic review was limited due to articles of small sample sizes and considerable heterogeneity, the results indicate that flow diverting devices and covered stents are good therapeutic options for endoluminal reconstruction of iatrogenic ICA injuries following endonasal surgery.