Endovascular Therapy For Intracranial Aneurysms Research Articles

Computational Flow Diverter Implantation—A Comparative Study on Pre-Interventional Simulation and Post-Interventional Device Positioning for a Novel Blood Flow Modulator

Due to their effect on aneurysm hemodynamics, flow diverters (FD) have become a routine endovascular therapy for intracranial aneurysms. Since over- and undersizing affect the device’s hemodynamic abilities, selecting the correct device diameter and accurately simulating FD placement can improve patient-specific outcomes. The purpose of this study was to validate the accuracy of virtual flow diverter deployments in the novel Derivo® 2 device. We retrospectively analyzed blood flows in ten FD placements for which 3D DSA datasets were available pre- and post-intervention. All patients were treated with a second-generation FD Derivo® 2 (Acandis GmbH, Pforzheim, Germany) and post-interventional datasets were compared to virtual FD deployment at the implanted position for implanted stent length, stent diameters, and curvature analysis using ANKYRAS (Galgo Medical, Barcelona, Spain). Image-based blood flow simulations of pre- and post-interventional configurations were conducted. The mean length of implanted FD was 32.61 (±11.18 mm). Overall, ANKYRAS prediction was good with an average deviation of 8.4% (±5.8%) with a mean absolute difference in stent length of 3.13 mm. There was a difference of 0.24 mm in stent diameter amplitude toward ANKYRAS simulation. In vessels exhibiting a high degree of curvature, however, relevant differences between simulated and real-patient data were observed. The intrasaccular blood flow activity represented by the wall shear stress was qualitatively reduced in all cases. Inflow velocity decreased and the pulsatility over the cardiac cycle was weakened. Virtual stenting is an accurate tool for FD positioning, which may help facilitate flow FDs’ individualization and assess their hemodynamic impact. Challenges posed by complex vessel anatomy and high curvatures must be addressed.

Toward the Development of a Shape Memory Polymer for Individualized Endovascular Therapy of Intracranial Aneurysms Using a 3D‐Printing/Leaching Method

Endovascular treatment of intracranial aneurysms (ICA) aims to occlude the aneurysm space to prevent ICA growth/rupture. Modern endovascular techniques are still limited by relatively low complete occlusion rates, frequently leading to aneurysm growth, rupture, and reoperation. Herein, shape memory polymer (SMP)‐based embolic devices are proposed to advance the effectiveness of ICA therapy by facilitating individualized ICA occlusion. Specifically, a 3D‐printing/leaching method for the fabrication of 3D‐SMP devices that can be tailored to patient‐specific aneurysm geometries obtained from computed tomography angiography is developed. It is demonstrated that this method allows the fabrication of highly porous, compressible foams with unique shape memory properties and customizable microstructure. In addition, the SMP foams exhibit great shape recovery, anisotropic mechanical properties, and the capability to occlude in vitro models with individualized geometries. Collectively, this study indicates that the proposed method will have the potential to advance the translation of coil‐ and stent‐free embolic devices for individualized treatment of saccular ICAs, targeting complete and long‐term durable aneurysm occlusion.

Diversified Endovascular Therapy for Intracranial Aneurysms : A Multifaceted Approach for Optimal Treatment

Diversified Endovascular Therapy for Intracranial Aneurysms : A Multifaceted Approach for Optimal Treatment

Transradial versus transfemoral access for endovascular therapy of intracranial aneurysms: a systematic review and meta-analysis of cohort studies.

Endovascular treatment is widely used in the treatment of intracranial aneurysms. However, neurosurgeons are sceptical about endovascular access via the radial artery. We performed a systematic review and meta-analysis to compare the effectiveness and safety of transradial and transfemoral artery access in patients with intracranial aneurysms. We systematically searched the PubMed, Embase, and Cochrane databases for studies comparing the two approaches. The primary outcome was total complications, and the secondary outcomes were access site complications, intracranial haemorrhage, stroke, thromboembolism, silent infarct, re-treatment rate, mortality, complete occlusion of intracranial aneurysms, procedure duration, and length of hospital stay. A random-effects model was used to assess the pooled data. Of the 100 identified studies, 6 were eligible (a total of 3764 participants). There were no significant differences in total complications(odds ratio [OR] = 0.69, 95% confidence interval [CI] [0.33, 1.45], p = 0.32), complete occlusion of intracranial aneurysms (OR = 1.02, 95%CI [0.77,1.37], p = 0.87), procedure duration (mean difference [MD] = - 6.24, 95%CI [- 14.75, - 1.54], p = 0.95), or length of hospital stay (MD = 2.204, 95%CI [- 0.05, 4.45], p = 0.95), access site complications (OR = 0.49, 95%CI [0.16, 1.52], p = 0.22), intracranial haemorrhage (OR = 1.07, 95%CI [0.49, 2.34], p = 0.86), stroke (OR = 0.59, 95%CI [0.20, 1.77], p = 0.35), thromboembolism (OR = 0.85, 95%CI [0.33, 2.17], p = 0.74), silent infarct (OR = 0.69, 95%CI [0.04, 11.80], p = 0.80), retreatment rate (OR = 1.32, 95%CI [0.70, 2.48], p = 0.39), mortality (OR = 1.41, 95%CI [0.06, 5.20], p = 0.61), immediate occlusion (OR = 0.99, 95%CI [0.64, 1.51], p = 0.95), and occlusion during follow-up (OR = 1.10, 95%CI [0.56, 2.16], p = 0.74) between the transradial and transfemoral groups. This study showed comparable safety and efficacy outcomes between transradial and transfemoral access in patients with intracranial aneurysms treated endovascularly. Future large randomised trials are warranted to confirm these findings.

The Evolution of Endovascular Therapy for Intracranial Aneurysms: Historical Perspective and Next Frontiers.

The history of cerebral aneurysm treatment has a rich and storied past with multiple notable luminaries contributing insights. The modern era has transitioned from primarily clip ligation to increasing use of endovascular therapy. Even more recently, the use of intrasaccular flow diverters has been introduced for the treatment of wide necked aneurysms. The field is continuing to transform, and bioactive coils and stents have resurfaced as promising adjuvants to promote aneurysm healing. Advanced imaging modalities are being developed that could further advance the endovascular arsenal and allow for porous memory polymer devices to enter the field. This focused review highlights notable historic contributions and advances to the point of futuristic technology that is actively being developed.

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.

The Utility of Diffusion-Weighted MRI Lesions to Compare the Effects of Different Heparinization Schemes in Intracranial Aneurysms Treated by Endovascular Intervention.

Objective: Heparinization is applied to prevent ischemic complications in the endovascular treatment of intracranial aneurysms, but there is no unified heparinization scheme. Diffusion-weighted imaging (DWI) can be used to evaluate ischemia after endovascular therapy for intracranial aneurysms. The goal of this study is to apply DWI to evaluate the effects of different heparinization schemes on intracranial aneurysms treated with endovascular therapy.Methods: We retrospectively reviewed 141 patients with 149 aneurysms treated with endovascular interventions from July 2019 to April 2020 at our center, including 96 aneurysms treated with local heparinization and 53 aneurysms treated with systemic heparinization. We collected the basic information of the patients, including age, sex, comorbidities, and aneurysm characteristics, and associated treatment data. New ischemic lesions detected by DWI were categorized belonging to four types. Multivariate logistic regression was used to compare the effects of different heparinization schemes on intracranial aneurysms treated with endovascular therapy.Results: There were no significant differences in age, sex, hypertension, diabetes, and aneurysm size or location between the two groups. The incidence and distribution types of DWI abnormalities in the local heparinization groups and systemic heparinization groups were not significantly different (P > 0.05). There was a correlation between the laser engraving stent and postoperative DWI abnormalities (P < 0.003). Multivariate logistic regression analysis showed that the laser engraving stent was significantly correlated with postoperative DWI abnormalities (odds ratio, 4.71; 95% CI: 1.51–14.58; P = 0.007).Conclusion: Compared with systemic heparinization, local heparinization does not increase the incidence of DWI abnormalities after endovascular treatment, and its application in this group of patients is safe and effective.

Risk Factors of Angiographic Recurrence After Endovascular Coil Embolization of Intracranial Saccular Aneurysms: A Retrospective Study Using a Multicenter Database

Background: Endovascular therapy of intracranial aneurysms has a high recurrence rate. This study aimed to evaluate the risk factors of recurrence after endovascular coil embolization of intracranial aneurysms.Methods: From January 2014 to May 2015, 504 patients with 558 intracranial aneurysms who were treated by endovascular therapy were recruited from four high-volume centers. We used multivariate Cox proportional hazard regression to evaluate the risk factors associated with the angiographic recurrence of intracranial saccular aneurysms after endovascular coil embolization.Results: Angiographic follow-up was available for 504 patients (558 aneurysms), with a mean duration of 11.42 months. Of the 558 aneurysms, 57 (10.2%) aneurysms showed recurrence. Aneurysm size (p = 0.028), therapy (non-stent assisted coiling or stent-assisted coiling) (p = 0.008), the Raymond scale (p = 0.040), aneurysm rupture status (p < 0.001), and packing density (p < 0.001) showed significant associations with angiographic follow-up outcome. A low packing density was independently associated with aneurysmal recurrence after multivariate Cox proportional hazard regression analysis (p < 0.001).Conclusion: Endovascular treatment is effective for these lesions. Multiple factors could attribute to the aneurysmal recurrence after endovascular coil embolization. The low packing density is the independent risk factor for aneurysmal recurrence. These findings should be verified by larger multicenter and multi-population studies.

Flow Diverters for Intracranial Aneurysms: The DIVERSION National Prospective Cohort Study.

Background and Purpose- Flow diverters are used for endovascular therapy of intracranial aneurysms. We did a nationwide prospective study to investigate the safety and effectiveness of flow diversion at 12 months. Methods- DIVERSION was a national prospective cohort study including all flow diverters placement between October 2012 and February 2014 in France. The primary end point was the event-free survival rate at 12 months, defined as the occurrence of morbidity (intracranial hemorrhage, ischemic stroke, noncerebral hemorrhage, or neurological deficit due to mass effect), retreatment, or death within 12 months post-treatment. A quality control was carried out on 100% of the collected data and of at least 10% of the included patients in each center, chosen at random. All reported serious events were adjudicated by an independent Data Safety and Monitoring Board. Satisfactory occlusion was defined as 3 or 4 on Kamran scale by an independent imaging core laboratory at 12 months. Results- We enrolled 398 patients harboring 477 intracranial aneurysms. At least 1 morbidity-mortality event was noted in 95 of 408 interventions representing an event-free survival rate of 75.7% (95% CI, 71.1-79.7). The rate of permanent-related serious events and mortality was 5.9% and 1.2% at 12 months, respectively. Multivariate analysis showed that high baseline blood pressure (hazard ratio, 2.54; 95% CI, 1.35-4.79; P=0.039), diabetes mellitus (hazard ratio, 3.70; 95% CI, 1.60-8.6; P=0.0022), and larger aneurysms (hazard ratio, 1.07; 95% CI, 1.04-1.11; P<0.0001) were associated with the occurrence of a neurological deficit. The satisfactory occlusion rate at 12 months was 79.9%, and the absence of high baseline blood pressure (odds ratio, 2.01; 95% CI, 1.12-3.71; P=0.0193) and postprocedural satisfactory occlusion (odds ratio, 2.75; 95% CI, 1.49-5.09; P=0.0012) were associated with a 12-month satisfactory occlusion. Conclusions- A satisfactory occlusion was achieved in almost 80% of cases after flow diverter treatment with a permanent-related serious event and mortality rates of 5.9% and 1.2% at 12 months, respectively.

Endovascular Treatment of Cerebral Aneurysms Not Presented by Classic Subarachnoid Hemorrhage (First Year Experience by Neurologist)

Saccular intracranial aneurysms are localized enlargement lesions of the vasculature, most commonly sited at bifurcation points in the circle of Willis. Often they will stay asymptomatic during the life. Its common presentation is rupture that leads to subarachnoid hemorrhage (SAH) but had other presentation as ischemic stroke or compressive symptoms. Material and Methods: we recruited 16 patients with intracranial aneurysm that had presentations other than subarachnoid hemorrhage and was treated by endovascular intervention and evaluated clinically and angiographically before procedure and 3-6 months after procedure Results: the mean age of patients was 5.75±11.1 ranging between 23 – 69 years. 10 patients were females and 6 were males. 7 patients (43.8 %) were hypertensive which was the commonest risk factor in those patients. 6 patients (37.5%) had ICA aneurysm. Conclusion: endovascular therapy of intracranial aneurysms is a safe and effective method of therapy with less morbidity and mortality rates.

Endovascular Treatment of Un-Ruptured Cerebral Aneurysms (Experience by Neurologist)

Saccular intracranial aneurysms are localized enlargement lesions of the vasculature, most commonly sited at bifurcation points in the circle of Willis. Un-ruptured intracranial aneurysms (UIA) are a common finding, occurring in about 2% of the population, making them very probable to be seen by most practitioners, and present a challenge in the recommendations for optimum management and screening. Most aneurysms do not rupture and patients harboring these lesions often remain asymptomatic. Material and Methods: we recruited 12 patients with un-ruptured intracranial aneurysms that was treated by endovascular intervention and evaluated clinically and angiographically before procedure and 3-6 months after procedure Results: the mean age of the patients was 51.42±11.23 ranging age 23 – 69 years. 6 were females and 6 were males. 5 patients (41.7 %) were hypertensive which was the commonest risk factor in those patients, 6 patients (50%) had ICA (Internal Carotid Artery) aneurysm. Conclusion: endovascular therapy of intracranial aneurysms is a safe and effective method of therapy with less morbidity and mortality rates.

Endovascular Treatment of Un-Ruptured Cerebral Aneurysms (Experience by Neurologist)

Saccular intracranial aneurysms are localized enlargement lesions of the vasculature, most commonly sited at bifurcation points in the circle of Willis. Un-ruptured intracranial aneurysms (UIA) are a common finding, occurring in about 2% of the population, making them very probable to be seen by most practitioners, and present a challenge in the recommendations for optimum management and screening. Most aneurysms do not rupture and patients harboring these lesions often remain asymptomatic. Material and Methods: we recruited 12 patients with un-ruptured intracranial aneurysms that was treated by endovascular intervention and evaluated clinically and angiographically before procedure and 3-6 months after procedure Results: the mean age of the patients was 51.42±11.23 ranging age 23 – 69 years. 6 were females and 6 were males. 5 patients (41.7 %) were hypertensive which was the commonest risk factor in those patients, 6 patients (50%) had ICA (Internal Carotid Artery) aneurysm. Conclusion: endovascular therapy of intracranial aneurysms is a safe and effective method of therapy with less morbidity and mortality rates.

The Woven EndoBridge (WEB) for endovascular therapy of intracranial aneurysms: Update of a systematic review with meta-analysis

ObjectivesEndovascular treatment of wide-neck intracranial aneurysms (IAs) is challenging, especially in bifurcation location. The intra-saccular flow-disruptor Woven EndoBridge (WEB) offers a new concept of endovascular therapy for wide-neck IAs. We performed an update of a systematic review aimed to report the feasibility, effectiveness and safety of WEB device therapy. Patients and methodsA systematic review was conducted using several electronic databases (including PUBMED and EMBASE), searching for studies published between October 2015 and December 2017 (those published between January 2010 and September 2015 were included in our initial systematic review). Outcomes were: success of implantation, peri-procedural complications, mortality, and adequate occlusion (complete occlusion or neck remnant). ResultsIn total (initial review + update), 12 uncontrolled case-series studies were included, reporting outcomes for 940 patients (68.6% female; mean age, 57 years) harboring 962 IAs. Most IAs were wide-neck bifurcation aneurysms (75%–100%), mainly at middle cerebral artery (37%) and anterior communicating artery (24.6%). Feasibility was 97% (95% confidence interval [CI], 95%–99%), and 9% (95%CI, 5%–14%) of cases required additional treatment. There were 14% (95%CI, 9%–19%) peri-procedural complications. After a median clinical follow-up of 7 months, mortality was 5% (95%CI, 1%–10%) and was higher in series with larger proportions of ruptured IAs. At last angiographic follow-up (median, 7 months; range, 3–27.9 months), adequate occlusion rate was 81% (95%CI, 73%–88%). ConclusionAlthough WEB showed high rates of adequate aneurysm occlusion at mid-term, procedure-related complications and mortality rates were not negligible. Future studies should compare the WEB device with other treatment options.

The 100 most cited articles in the endovascular management of intracranial aneurysms

IntroductionEndovascular interventions for intracranial aneurysms have evolved substantially over the past several decades. A citation rank list is used to measure the scientific and/or clinical impact of an article. Our...

A Review of Recent Advances in Endovascular Therapy for Intracranial Aneurysms.

Despite the advances in neuro-interventional techniques and expertise to treat intracranial aneurysms (IAs), there remains a subset of IAs that are considered to be a significant treatment challenge. Working closely with the neuro-interventional community, bioengineers have harnessed their knowledge of anatomy, physiology, biophysics, and new materials to develop novel therapeutic adjuncts for the successful endovascular treatment of simple and complex IAs. This review describes the biological challenges, the landscape of neuro-interventional management of IAs, and the factors pertinent to which therapeutic modality is recommended. Finally, recent technological advances that have emerged over the last decade are discussed, taking the reader through the devices' objectives, utility, and safety profiles. The goal of this review is to (i) provide physicians treating IAs with the pertinent information to facilitate evidence-based clinical decision thereby minimizing morbidity and mortality and (ii) facilitate professionals in the biomedical engineering field with the clinical background and summarize current endovascular IA treatment options available, with the intent to inspire future IA device development and innovation.

More Transparency Is Needed in the Reporting of Clinical Research Studies

We read with great interest the systematic review published very recently by Asnafi et al[1][1] on the efficacy and safety of the Woven EndoBridge (WEB); (Sequent Medical, Aliso Viejo, California) aneurysm embolization system for the endovascular therapy of intracranial aneurysms. Their literature

One-Year Angiographic Follow-Up after WEB-SL Endovascular Treatment of Wide-Neck Bifurcation Intracranial Aneurysms.

Endovascular coiling of wide-neck intracranial aneurysms is associated with low rates of initial angiographic occlusion and high rates of recurrence. The WEB intrasaccular device has been developed specifically for this indication. To date, there has been no report of the long-term follow-up of a series of patients with aneurysms treated with this type of device, to our knowledge. Our aim was to evaluate a 1-year follow-up of angiographic results in a prospective single-center series of patients treated with the WEB-Single-Layer (SL) device. All patients treated with the WEB-SL device in our center between August 2013 and May 2014 were prospectively included. One-year angiographic outcomes were assessed. Results at follow-up were graded as complete occlusion, neck remnant, or residual aneurysm. Eight patients with 8 unruptured wide-neck aneurysms were enrolled in this study. Average dome width was 7.5 mm (range, 5.4-10.7 mm), and average neck size was 4.9 mm (range, 2.6-6.5 mm). One-year angiographic follow-up obtained in all aneurysms included 1 complete aneurysm occlusion (12.5%), 6 neck remnants (75%), and 1 aneurysm remnant (12.5%). Of 8 aneurysms, worsening of aneurysm occlusion was observed in 2 (25%) by compression of the WEB device. There was no angiographic recurrence of initially totally occluded aneurysms. No bleeding was observed during the follow-up period. Endovascular therapy of intracranial aneurysms with the WEB-SL device allows treatment of wide-neck aneurysms with a high rate of neck remnant at 1 year, at least partially explained by WEB compression. Initial size selection and technologic improvements could be an option for optimization of aneurysm occlusion in WEB-SL treatment.

High-fidelity virtual stenting: modeling of flow diverter deployment for hemodynamic characterization of complex intracranial aneurysms.

Flow diversion via Pipeline Embolization Device (PED) represents the most recent advancement in endovascular therapy of intracranial aneurysms. This exploratory study aims at a proof of concept for an advanced device-modeling tool in conjunction with computational fluid dynamics (CFD) to evaluate flow modification effects by PED in actual, treated cases. The authors performed computational modeling of 3 PED-treated complex aneurysm cases. The patient in Case 1 had a fusiform vertebral aneurysm treated with a single PED. In Case 2 the patient had a giant internal carotid artery (ICA) aneurysm treated with 2 PEDs. Case 3 consisted of tandem ICA aneurysms (III-a and III-b) treated by a single PED. The authors' recently developed high-fidelity virtual stenting (HiFiVS) technique was used to recapitulate the clinical deployment process of PEDs in silico for these 3 cases. Pretreatment and posttreatment aneurysmal hemodynamics studies performed using CFD simulation were analyzed. Changes in aneurysmal flow velocity, inflow rate, wall shear stress (WSS), and turnover time were calculated and compared with the clinical outcome. In Case 1 (occluded within the first 3 months), the aneurysm had the most drastic flow reduction after PED placement; the aneurysmal average velocity, inflow rate, and average WSS were decreased by 76.3%, 82.5%, and 74.0%, respectively, whereas the turnover time was increased to 572.1% of its pretreatment value. In Case 2 (occluded at 6 months), aneurysmal average velocity, inflow rate, and average WSS were decreased by 39.4%, 38.6%, and 59.1%, respectively, and turnover time increased to 163.0%. In Case 3, Aneurysm III-a (occluded at 6 months) had a decrease by 38.0%, 28.4%, and 50.9% in average velocity, inflow rate, and average WSS, respectively, and turnover time increased to 139.6%, which was quite similar to Aneurysm II. Surprisingly, the adjacent Aneurysm III-b had more substantial flow reduction (a decrease by 77.7%, 53.0%, and 84.4% in average velocity, inflow rate, and average WSS, respectively, and an increase to 213.0% in turnover time) than Aneurysm III-a, which qualitatively agreed with angiographic observation at 3-month follow-up. However, Aneurysm III-b remained patent at both 6 months and 9 months. A closer examination of the vascular anatomy in Case 3 revealed blood draining to the ophthalmic artery off Aneurysm III-b, which may have prevented its complete thrombosis. This proof-of-concept study demonstrates that HiFiVS modeling of flow diverter deployment enables detailed characterization of hemodynamic alteration by PED placement. Posttreatment aneurysmal flow reduction may be correlated with aneurysm occlusion outcome. However, predicting aneurysm treatment outcome by flow diverters also requires consideration of other factors, including vascular anatomy.

Development of Endovascular Therapy for Intracranial Aneurysms

Development of Endovascular Therapy for Intracranial Aneurysms

P-041 Enhanced procedural guidance during deployment of flow-diverters using 3D land marking and overlay technique

PurposeEndoluminal parent vessel reconstruction using flow-diverting device has emerged as a viable alternative to stent-assisted coiling/surgical clipping in wide necked intracranial aneurysms.1 Accurate device positioning in parent vessel and deployment...