Cerecyte coil trial: procedural safety and clinical outcomes in patients with ruptured and unruptured intracranial aneurysms

Letter to editor: Bridging the gap: robotic applications in cerebral aneurysms neurointerventions - a systematic review

The letter critically evaluates the role of robotic applications in cerebral aneurysm neurointerventions, synthesizing a diverse array of studies to elucidate both the potential benefits and inherent limitations of this emerging technology. The review highlights the advancements in precision, efficiency, and patient outcomes facilitated by robotic platforms, while also acknowledging challenges such as the steep learning curve and the need for further research to establish long-term efficacy and cost-effectiveness. By navigating through the complexities of robotic-assisted neurosurgery, the review provides valuable insights into the transformative potential of robotics in optimizing treatment paradigms and improving patient care.

Bridging the gap: robotic applications in cerebral aneurysms neurointerventions - a systematic review

Cerebral aneurysm is a life-threatening condition, which requires high precision during the neurosurgical procedures. Increasing progress of evaluating modern devices in medicine have led to common usage of robotic systems in many fields, including cranial aneurysm operations. However, currently no systematic review describes up-to date knowledge of this topic. Following PRISMA guidelines, we have independently screened and extracted works from seven databases. Only studies fulfilling inclusion criteria were presented in this study. Device used, operation time, complications, aneurysm type and patient demographics were extracted from each work. We identified a total of 995 articles from databases. We have found six original works and one supplementary article eligible for this synthesis. Majority of works (4/6) have implemented CorPath GRX in cerebral aneurysm procedures. The procedures involved diverse aneurysm locations, utilizing flow diverters, stents, or coiling. One study described implementation of robot-assist on 117 patients and compared results to randomized clinical trials. One work with a small patient cohort described use of the magnetically-controlled microguidewire in the coiling procedures, without any complications. Additionally, one case-series study described use of a robotic arm for managing intraoperative aneurysm rupture. Currently, robotical devices for cerebral aneurysm treatment mainly lack jailing and haptic feedback feature. Further development of these devices will certainly be beneficial for operators and patients, allowing for more precise and remote surgeries.

Evaluation of effectiveness and safety of the CorPath GRX robotic system in endovascular embolization procedures of cerebral aneurysms

BACKGROUND

Robotic-assisted neurointervention was recently introduced, with implications that it could be used to treat neurovascular diseases.

OBJECTIVE

To evaluate the effectiveness and safety of the robotic-assisted platform CorPath GRX for treating cerebral aneurysms.

METHODS

This prospective, international, multicenter study enrolled patients with brain aneurysms that required endovascular coiling and/or stent-assisted coiling. The primary effectiveness endpoint was defined as successful completion of the robotic-assisted endovascular procedure without any unplanned conversion to manual treatment with guidewire or microcatheter navigation, embolization coil(s) or intracranial stent(s) deployment, or an inability to navigate vessel anatomy. The primary safety endpoint included intraprocedural and periprocedural events.

RESULTS

The study enrolled 117 patients (74.4% female) with mean age of 56.6 years from 10 international sites,. Headache was the most common presenting symptom in 40/117 (34.2%) subjects. Internal carotid artery was the most common location (34/122, 27.9%), and the mean aneurysm height and neck width were 5.7±2.6 mm and 3.5±1.4 mm, respectively. The overall procedure time was 117.3±47.3 min with 59.4±32.6 min robotic procedure time. Primary effectiveness was achieved in 110/117 (94%) subjects with seven subjects requiring conversion to manual for procedure completion. Only four primary safety events were recorded with two intraprocedural aneurysm ruptures and two strokes. A Raymond-Roy Classification Scale score of 1 was achieved in 71/110 (64.5%) subjects, and all subjects were discharged with a modified Rankin Scale score of ≤2.

CONCLUSIONS

This first-of-its-kind robotic-assisted neurovascular trial demonstrates the effectiveness and safety of the CorPath GRX System for endovascular embolization of cerebral aneurysm procedures.

TRIAL REGISTRATION NUMBER

NCT04236856.

Clipping versus coiling: A critical re-examination of a decades old controversy

BACKGROUND

Two major studies, The International Subarachnoid Aneurysm Trial and the Barrow Ruptured Aneurysm Trial, compare the long-term outcomes of clipping and coiling. Although these demonstrated coiling's initial benefits, rebleeding and retreatment rates as well as converging patient outcomes sparked controversy regarding its durability. This article will critically examine the available evidence for and against clipping and coiling of intracranial aneurysms. Critics of endovascular treatment state that the initial benefit seen with endovascular coiling decreases over the duration of follow-up and eventually functional outcomes of both treatment modalities are similar. Combined with the increased rate of retreatment and rebleeding, these trials reveal that coiling is not as durable and not as effective as a long-term treatment compared to clipping. Also, due to the cost of devices following endovascular treatment and prolonged hospitalization following clipping, the financial burden has been considered controversial.

SUMMARY/KEY MESSAGES

Short-term outcomes reveal better morbidity and mortality outcomes following coiling. Despite the higher rates of retreatment and rebleeding with coiling, there was no significant change in functional outcomes following retreatment. Furthermore, examining more recent trials reveals a decreased rate of recurrence and rebleeding with improved technology and expertise. Functional outcomes deteriorate for both cohorts over time while recent results revealed improved long-term cognitive outcomes and levels of health-related quality of life after coiling in comparison to clipping. The expense of longer hospital stays following clipping must be balanced against the expense of endovascular devices in coiling.

Outcomes Associated With Intracranial Aneurysm Treatments Reported as Safe, Effective, or Durable: A Systematic Review and Meta-Analysis

Importance

Testing new medical devices or procedures in terms of safety, effectiveness, and durability should follow the strictest methodological rigor before implementation.

Objectives

To review and analyze studies investigating devices and procedures used in intracranial aneurysm (IA) treatment for methods and completeness of reporting and to compare the results of studies with positive, uncertain, and negative conclusions.

Data Sources

Embase, MEDLINE, Web of Science, and The Cochrane Central Register of Clinical Trials were searched for studies on IA treatment published between January 1, 1995, and the October 1, 2022. Grey literature was retrieved from Google Scholar.

Study Selection

All studies making any kind of claims of safety, effectiveness, or durability in the field of IA treatment were included.

Data Extraction and Synthesis

Using a predefined data dictionary and analysis plan, variables ranging from patient and aneurysm characteristics to the results of treatment were extracted, as were details pertaining to study methods and completeness of reporting. Extraction was performed by 10 independent reviewers. A blinded academic neuro-linguist without involvement in IA research evaluated the conclusion of each study as either positive, uncertain, or negative. The study followed Preferring Reporting Items for Systematic Reviews and Meta-Analyses guidelines.

Main Outcomes and Measures

The incidence of domain-specific outcomes between studies with positive, uncertain, or negative conclusions regarding safety, effectiveness, or durability were compared. The number of studies that provided a definition of safety, effectiveness, or durability and the incidence of incomplete reporting of domain-specific outcomes were evaluated.

Results

Overall, 12 954 studies were screened, and 1356 studies were included, comprising a total of 410 993 treated patients. There was no difference in the proportion of patients with poor outcome or in-hospital mortality between studies claiming a technique was safe, uncertain, or not safe. Similarly, there was no difference in the proportion of IAs completely occluded at last follow-up between studies claiming a technique was effective, uncertain, or noneffective. Less than 2% of studies provided any definition of safety, effectiveness, or durability, and only 1 of the 1356 studies provided a threshold under which the technique would be considered unsafe. Incomplete reporting was found in 546 reports (40%).

Conclusions and Relevance

In this systematic review and meta-analysis of IA treatment literature, studies claiming safety, effectiveness, or durability of IA treatment had methodological flaws and incomplete reporting of relevant outcomes supporting these claims.

A Pragmatic Randomized Trial Comparing Surgical Clipping and Endovascular Treatment of Unruptured Intracranial Aneurysms

BACKGROUND AND PURPOSE

Surgical clipping and endovascular treatment are commonly used in patients with unruptured intracranial aneurysms. We compared the safety and efficacy of the 2 treatments in a randomized trial.

MATERIALS AND METHODS

Clipping or endovascular treatments were randomly allocated to patients with one or more 3- to 25-mm unruptured intracranial aneurysms judged treatable both ways by participating physicians. The study hypothesized that clipping would decrease the incidence of treatment failure from 13% to 4%, a composite primary outcome defined as failure of aneurysm occlusion, intracranial hemorrhage during follow-up, or residual aneurysms at 1 year, as adjudicated by a core lab. Safety outcomes included new neurologic deficits following treatment, hospitalization of >5 days, and overall morbidity and mortality (mRS > 2) at 1 year. There was no blinding.

RESULTS

Two hundred ninety-one patients were enrolled from 2010 to 2020 in 7 centers. The 1-year primary outcome, ascertainable in 290/291 (99%) patients, was reached in 13/142 (9%; 95% CI, 5%-15%) patients allocated to surgery and in 28/148 (19%; 95% CI, 13%-26%) patients allocated to endovascular treatments (relative risk: 2.07; 95% CI, 1.12-3.83; P = .021). Morbidity and mortality (mRS >2) at 1 year occurred in 3/143 and 3/148 (2%; 95% CI, 1%-6%) patients allocated to surgery and endovascular treatments, respectively. Neurologic deficits (32/143, 22%; 95% CI, 16%-30% versus 19/148, 12%; 95% CI, 8%-19%; relative risk: 1.74; 95% CI, 1.04-2.92; P = .04) and hospitalizations beyond 5 days (69/143, 48%; 95% CI, 40%-56% versus 12/148, 8%; 95% CI, 5%-14%; relative risk: 0.18; 95% CI, 0.11-0.31; P < .001) were more frequent after surgery.

CONCLUSIONS

Surgical clipping is more effective than endovascular treatment of unruptured intracranial aneurysms in terms of the frequency of the primary outcome of treatment failure. Results were mainly driven by angiographic results at 1 year.

CFD to Quantify Idealized Intra-Aneurysmal Blood Flow in Response to Regular and Flow Diverter Stent Treatment

Cerebral aneurysms are pathological dilatations of the vessels supplying the brain. They carry a certain risk of rupture, which in turn, results in a high risk of mortality and morbidity. Flow diverters (FDs) are high-density meshed stents which are implanted in the vessel segment harboring an intracranial aneurysm to cover the entrance of the aneurysm, thus reducing the blood flow into the aneurysm, promoting thrombosis formation and stable occlusion, which prevents rupture or growth of the aneurysm. In the present study, the blood flow in an idealized aneurysm, treated with an FD stent and a regular stent (RS), were modeled and analyzed considering their design, surface area porosity, and flow reduction to investigate the quantitative and qualitative effect of the stent on intra-aneurysmal hemodynamics. CFD simulations were conducted before and after treatment. Significant reductions were observed for most hemodynamic variables with the use of stents, during both the peak systolic and late diastolic cardiac cycles. FD reduces the intra-aneurysmal wall shear stress (WSS), inflow, and aneurysmal flow velocity, and increases the turnover time when compared to the RS; therefore, the possibility of aneurysm thrombotic occlusion is likely to increase, reducing the risk of rupture in cerebral aneurysms.

Temperature-responsive biodegradable injectable polymers with tissue adhesive properties

Injectable polymers (IPs) exhibiting in situ hydrogel formation have attracted attention as vascular embolization and postoperative adhesion prevention materials. While utilizing hydrogels for such purposes, it is essential to ensure that they have appropriate and controllable tissue adhesion property, as it is crucial for them to not detach from their deposited location in the blood vessel or abdominal cavity. Additionally, it is important to maintain gel state in vivo for the desired period at such locations, where large amounts of body fluid exist. We had previously reported on a biodegradable IP system exhibiting temperature-responsive gelation and subsequent covalent cross-link formation. We had utilized triblock copolymers of aliphatic polyester and poly(ethylene glycol) (tri-PCGs) and its derivative containing acrylate group at the termini (tri-PCG-Acryl), exhibiting a longer and more controllable duration time of the gel state. In this study, the introduction of aldehyde groups by the addition of aldehyde-modified Pluronic (PL-CHO) was performed for conferring controllable and appropriate tissue adhesive properties on these IP systems. The IP systems containing PL-CHO, which were not covalently incorporated into the hydrogel network, exhibited tissue adhesive properties through Schiff base formation. The adhesion strength could be controlled by the amount of PL-CHO added. The IP system showed good vascular embolization performance and pressure resistance in the blood vessels. The IP hydrogel remained at the administration site in the abdominal space for 2 days and displayed effective adhesion prevention performance. STATEMENT OF SIGNIFICANCE: Injectable polymers (IPs), which exhibit in situ hydrogel formation, are expected to be utilized as vascular embolization and postoperative adhesion prevention materials. The tissue adhesion properties of hydrogels are important for such applications. We succeeded in conferring tissue adhesion properties onto a previously reported IP system by mixing it with Pluronic modified with aldehyde groups (PL-CHO). The aldehyde groups allowed for the formation of Schiff bases at the tissue surfaces. The tissue adhesion property could be conveniently controlled by altering the amount of PL-CHO. We revealed that the in vitro embolization properties of IPs in blood vessels could be substantially improved by mixing with PL-CHO. The IP system containing PL-CHO also exhibited good in vivo performance for postoperative adhesion prevention.

In vitro cytocompatibility testing of oxidative degradation products

Implantable medical devices must undergo thorough evaluation to ensure safety and efficacy before use in humans. If a device is designed to degrade, it is critical to understand the rate of degradation and the degradation products that will be released. Oxidative degradation is typically modeled in vitro by immersing materials or devices in hydrogen peroxide, which can limit further analysis of degradation products in many cases. Here we demonstrate a novel approach for testing the cytocompatibility of degradation products for oxidatively-degradable biomaterials where the materials are exposed to hydrogen peroxide, and then catalase enzyme is used to convert the hydrogen peroxide to water and oxygen so that the resulting aqueous solution can be added to cell culture media. To validate our results, expected degradation products are also synthesized then added to cell culture media. We used these methods to evaluate the cytocompatibility of degradation products from an oxidatively-degradable shape memory polyurethane designed in our lab and found that the degradation of these polymers is unlikely to cause a cytotoxic response in vivo based on the guidance provided by ISO 10993-5. These methods may also be applicable to other biocompatibility tests such as tests for mutagenicity or systemic toxicity, and evaluations of cell proliferation, migration, or gene and protein expression.

Impact of Treatment Delay on Outcome in the International Subarachnoid Aneurysm Trial

Background and Purpose- ISAT (International Subarachnoid Aneurysm Trial) demonstrated that 1 year after aneurysmal subarachnoid hemorrhage, coiling resulted in a significantly better clinical outcome than clipping. After 5 years, this difference did not reach statistical significance, but mortality was still higher in the clipping group. Here, we present additional analyses, reporting outcome after excluding pretreatment deaths. Methods- Outcome measures were death with or without dependency at 1 and 5 years after treatment, after exclusion of all pretreatment deaths. Treatment differences were assessed using relative risks (RRs). With sensitivity and exploratory analyses, the relation between treatment delay and outcome was analyzed. Results- After exclusion of pretreatment deaths, at 1-year follow-up coiling was favorable over clipping for death or dependency (RR, 0.77 [95% CI, 0.67-0.89]) but not for death alone (RR, 0.88 [95% CI, 0.66-1.19]). After 5 years, no significant differences were observed, neither for death or dependency (RR, 0.88 [95% CI, 0.77-1.02]) nor for death alone (RR, 0.82 [95% CI, 0.64-1.05]). Sensitivity analyses showed a similar picture. In good-grade patients, coiling remained favorable over clipping in the long-term. Time between randomization and treatment was significantly longer in the clipping arm (mean 1.7 versus 1.1 days; P<0.0001), during which 17 patients died because of rebleeding versus 6 pretreatment deaths in the endovascular arm (RR, 2.81 [95% CI, 1.11-7.11]). Conclusions- These additional analyses support the conclusion of ISAT that at 1-year follow-up after aneurysmal subarachnoid hemorrhage coiling has a better outcome than clipping. After 5 years, with pretreatment mortality excluded, the difference between coiling and clipping is not significant. The high number of pretreatment deaths in the clipping group highlights the importance of urgent aneurysm treatment to prevent early rebleeding.

In Situ Generated Medical Devices

Medical devices play a major role in all areas of modern medicine, largely contributing to the success of clinical procedures and to the health of patients worldwide. They span from simple commodity products such as gauzes and catheters, to highly advanced implants, e.g., heart valves and vascular grafts. In situ generated devices are an important family of devices that are formed at their site of clinical function that have distinct advantages. Among them, since they are formed within the body, they only require minimally invasive procedures, avoiding the pain and risks associated with open surgery. These devices also display enhanced conformability to local tissues and can reach sites that otherwise are inaccessible. This review aims at shedding light on the unique features of in situ generated devices and to underscore leading trends in the field, as they are reflected by key developments recently in the field over the last several years. Since the uniqueness of these devices stems from their in situ generation, the way they are formed is crucial. It is because of this fact that in this review, the medical devices are classified depending on whether their in situ generation entails chemical or physical phenomena.

Effects of propofol versus sevoflurane on cerebral circulation time in patients undergoing coiling for cerebral artery aneurysm: a prospective randomized crossover study

Many neuroendovascular treatments are supported by real-time anatomical and visual hemodynamic assessments through digital subtraction angiography (DSA). Here we used DSA in a single-center prospective randomized crossover study to assess the intracranial hemodynamics of patients undergoing coiling for cerebral aneurysm (n = 15) during sevoflurane- and propofol-based anesthesia. Color-coded DSA was used to define time to peak density of contrast medium (TTP) at several intravascular regions of interest (ROIs). Travel time at a particular ROI was defined as the TTP at the selected ROI minus TTP at baseline position on the internal carotid artery (ICA). Travel time at the jugular bulb on the anterior-posterior view was defined as the cerebral circulation time (CCT), which was divided into four segmental circulation times: ICA, middle cerebral artery (MCA), microvessel, and sinus. When bispectral index values were kept between 40 and 60, CCT (median [interquartile range]) was 10.91 (9.65-11.98) s under propofol-based anesthesia compared with 8.78 (8.32-9.45) s under sevoflurane-based anesthesia (P < 0.001). Circulation times for the ICA, MCA, and microvessel segments were longer under propofol-based anesthesia than under sevoflurane-based anesthesia (P < 0.05 for all). Our results suggest that, relative to sevoflurane, propofol decreases overall cerebral perfusion.

Bailout Strategies and Complications Associated with the Use of Flow-Diverting Stents for Treating Intracranial Aneurysms

Background

Flow-diverting stents (FDS) have revolutionized the endovascular management of unruptured, complex, wide-necked, and giant aneurysms. There is no consensus on management of complications associated with the placement of these devices. This review focuses on the management of complications of FDS for the treatment of intracranial aneurysms.

Summary

We performed a systematic, qualitative review using electronic databases MEDLINE and Google Scholar. Complications of FDS placement generally occur during the perioperative period.

Key Message

Complications associated with FDS may be divided into periprocedural complications, immediate postprocedural complications, and delayed complications. We sought to review these complications and novel management strategies that have been reported in the literature.

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

INTRODUCTION

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

METHODS AND ANALYSIS

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

ETHICS AND DISSEMINATION

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

TRIAL REGISTRATION NUMBER

NCT03133598.

Endovascular embolization of branch-incorporated cerebral aneurysms

Objectives The aim of this study was to examine the feasibility, technique, and clinical and angiographic outcomes of endovascular coiling to treat a cerebral aneurysm with a branch incorporated into the aneurysmal wall. Methods From 2012 to 2016, 25 patients with 26 cerebral aneurysms having a branch incorporated into the aneurysm (9 unruptured, 17 ruptured) were treated to prevent rupture or re-bleeding from the sac while preserving the incorporated branch by using single-catheter ( n = 18), balloon-remodeling ( n = 4), stent-assisted coiling ( n = 3), or double-catheter ( n = 1) techniques. Results Endovascular coiling was conducted in 26 procedures without angiographic occlusion of the incorporated branch. Post-embolization angiography revealed near-complete occlusion ( n = 8; 30.7%), neck remnant ( n = 13; 50%), and incomplete occlusion ( n = 5; 19.3%) aneurysms. Thromboembolisms were observed in four (15.4%) patients during or after the procedure. A procedure-related neurological deficit was observed in one (3.8%) patient. When patients with a preictal modified Rankin Scale (mRS) score of 3 presenting with grade 5 subarachnoid hemorrhage were excluded, all patients had favorable outcomes (mRS 0-2). Six (23.1%) recurrent aneurysms were observed during follow-up, five of which were treated endovascularly at 5-22 months without complication. The location of an aneurysm at the ICA-posterior communicating artery associated with the dominant-type posterior communicating artery was significantly associated with recurrence ( p = 0.041). Conclusions Cerebral aneurysms with an incorporated branch were safely treated using conventional endovascular coiling. However, treatment durability was unsatisfactory, especially for dominant-type ICA-posterior communicating artery aneurysms.

Rescue Therapy for Procedural Complications Associated With Deployment of Flow-Diverting Devices in Cerebral Aneurysms

Flow diverting devices (FDDs) have revolutionized the treatment of morphologically complex intracranial aneurysms such as wide-necked, giant, or fusiform aneurysms. Although FDDs are extremely effective, they carry a small yet significant risk of intraprocedural complications. As the implementation of these devices increases, the ability to predict and rapidly treat complications, especially those that are iatrogenic or intraprocedural in nature, is becoming increasingly more necessary.

Our objective in this paper is to provide a descriptive summary of the various types of intraprocedural complications that may occur during FDDs deployment and how they may best be treated. A systematic and qualitative review of the literature was conducted using electronic databases MEDLINE and Google Scholar. Searches consisted of Boolean operators “AND” and “OR” for the following terms in different combinations: “aneurysm,” “endovascular,” “flow diverter,” “intracranial,” and “pipeline.”

A total of 94 papers were included in our analysis; approximately 87 of these papers dealt with periprocedural endovascular (mainly related to FDDs) complications and their treatment; 7 studies concerned background material. The main categories of periprocedural complications encountered during deployment of FDDs are failure of occlusion, parent vessel injury and/or rupture, spontaneous intraparenchymal hemorrhage, migration or malposition of the FDDs, thromboembolic or ischemic events, and side branch occlusion

Periprocedural complications occur mainly due to thromboembolic events or mechanical issues related to device deployment and placement. With increasing use and expanding versatility of FDDs, the understanding of these complications is vital in order to effectively manage such situations in a timely manner.

How safe and effective are existing treatments for wide-necked bifurcation aneurysms? Literature-based objective performance criteria for safety and effectiveness

Introduction

Wide-necked bifurcation aneurysms (WNBAs) present unique technical challenges for both endovascular and surgical treatments which aim to achieve complete occlusion of the aneurysm without compromising the patency of the incorporated regional parent vessels. We present a meta-analysis of traditional therapies for WNBAs to provide critical benchmarks for safety and effectiveness.

Methods

Following a systematic search of the literature and the application of pre-specified appropriateness criteria, 43 (including 2794 aneurysms treated) and 65 (including 5366 patients treated) references with sufficient detail were identified to include in a meta-analysis of efficacy and safety, respectively. Effectiveness endpoints of both complete and adequate occlusion were assessed. A composite safety endpoint was based upon commonly applied metrics for major adverse events. Fleiss analyses were performed for both effectiveness and safety endpoints for the entire group, and then parsed separately by treatment modality (surgical clipping (SC) or endovascular therapy (EVT)) and location (anterior or posterior circulation).

Results

Using the above methods, the core laboratory adjusted rate of complete occlusion was 46.3% (standard error 3.6%), 39.8% (3.7%), and 52.5% (9.6%) for all therapies, EVT, and SC, respectively. The rate of adequate occlusion was 59.4% (12.2%), 43.8% (5.3%), and 69.7% (14.3%) for all therapies, EVT, and SC, respectively. The rates of occurrence for pre-specified safety endpoints were 18.7% (2.9%), 21.1% (2.8%), and 24.3% (4.9%) for all therapies, EVT, and SC, respectively.

Conclusions

Conventional therapies for WNBAs are associated with relatively low rates of complete occlusion and peri-procedural complications are not uncommon. As new treatment technologies are investigated, it is important that the available data regarding predicate treatments is understood.

Hydrogel versus Bare Platinum Coils in Patients with Large or Recurrent Aneurysms Prone to Recurrence after Endovascular Treatment: A Randomized Controlled Trial

BACKGROUND AND PURPOSE

Some patients are at high risk of aneurysm recurrence after endovascular treatment: patients with large aneurysms (Patients Prone to Recurrence After Endovascular Treatment PRET-1) or with aneurysms that have previously recurred after coiling (PRET-2). We aimed to establish whether the use of hydrogel coils improved efficacy outcomes compared with bare platinum coils.

MATERIALS AND METHODS

PRET was an investigator-led, pragmatic, multicenter, parallel, randomized (1:1) trial. Randomized allocation was performed separately for patients in PRET-1 and PRET-2, by using a Web-based platform ensuring concealed allocation. The primary outcome was a composite of a residual/recurrent aneurysm, adjudicated by a blinded core laboratory, or retreatment, intracranial bleeding, or mass effect during the 18-month follow-up. Secondary outcomes included adverse events, mortality, and morbidity (mRS > 2). The hypothesis was that hydrogel would decrease the primary outcome from 50% to 30% at 18 months, necessitating 125 patients per group (500 for PRET-1 and PRET-2).

RESULTS

The trial was stopped once 250 patients in PRET-1 and 197 in PRET-2 had been recruited because of slow accrual. A poor primary outcome occurred in 44.4% (95% CI, 35.5%-53.2%) of those in PRET-1 allocated to platinum compared with 52.5% (95% CI, 43.4%-61.6%) of patients allocated to hydrogel (OR, 1.387; 95% CI, 0.838-2.295; P = .20) and in 49.0% (95% CI, 38.8%-59.1%) in PRET-2 allocated to platinum compared with 42.1% (95% CI, 32.0%-52.2%) allocated to hydrogel (OR, 0.959; 95% CI, 0.428-1.342; P = .34). Adverse events and morbidity were similar. There were 3.6% deaths (1.4% platinum, 5.9% hydrogel; P = .011).

CONCLUSIONS

Coiling of large and recurrent aneurysms is safe but often poorly effective according to angiographic results. Hydrogel coiling was not shown to be better than platinum.

Evaluation of Pipeline Flex delivery system for the treatment of unruptured aneurysms

INTRODUCTION

Refinements in endovascular technology have revolutionized the treatment of intracranial aneurysms (IAs) with the development of flow-diversion technology. The first generation of the Pipelin Embolization Device (PED) has demonstrated its safety and efficacy. However, the deployment technique was a difficult task that often led to complex maneuvers. The Pipeline Flex Embolization Device (PED Flex) is the second generation and its introduction has arrived with high expectations due to a completely redesigned delivery system that intends to overcome deployment difficulties seen in the previous generation. Areas covered: Preclinical studies, mechanism of action of flow-diverters, technical aspects and deployment system of the PED Flex, and clinical outcomes with both PED generations. Expert commentary: Flow diversion has allowed us to treat lesions that would be otherwise challenging for surgical clipping or unsuitable for other endosaccular strategies. Although the experience with PED Flex is limited, initial results suggest its safety and short-term efficacy.

Novel Hydrogel Material as a Potential Embolic Agent in Embolization Treatments

We report a novel graphene-oxide (GO) enhanced polymer hydrogel (GPH) as a promising embolic agent capable of treating cerebrovascular diseases and malignant tumors, using the trans-catheter arterial embolization (TAE) technique. Simply composed of GO and generation five poly(amidoamine) dendrimers (PAMAM-5), our rheology experiments reveal that GPH exhibits satisfactory mechanical strength, which resist the high pressures of blood flow. Subcutaneous experiments on Sprague-Dawley (SD) rats demonstrate the qualified biocompatibility of GPH. Finally, our in vivo experiments on New Zealand rabbits, which mix GPH with the X-ray absorbing contrast agent, Iohexol, reveal complete embolization of the artery. We also note that GPH shortens embolization time and exhibits low toxicity in follow-up experiments. Altogether, our study demonstrates that GPH has many advantages over the currently used embolic agents and has potential applications in clinical practice.

Bipolar radiofrequency ablation of aneurysm remnants after coil embolization can improve endovascular treatment of experimental bifurcation aneurysms

OBJECTIVE Endovascular treatment of aneurysms may result in incomplete initial occlusion and aneurysm recurrence at angiographic follow-up studies. This study aimed to assess the feasibility and efficacy of bipolar radiofrequency ablation (RFA) of aneurysm remnants after coil embolization. METHODS Bipolar RFA was accomplished using the coil mass as 1 electrode, while the second electrode was a stent placed across the aneurysmal neck. After preliminary experiments and protocol approval from the Animal Care committee, wide-necked bifurcation aneurysms were constructed in 24 animals. Aneurysms were allocated to 1 of 3 groups: partial intraoperative coil embolization, followed by RFA (n = 12; treated group) or without RFA (n = 6; control group 1); or attempted complete endovascular coil embolization 2-4 weeks later (n = 6; control group 2). Angiographic results were compared at baseline, immediately after RFA, and at 12 weeks, using an ordinal scale. Pathological results and neointima formation at the neck were compared using a semiquantitative grading scale. RESULTS Bipolar RFA was able to reliably target the aneurysm neck when the coil mass and stent were used as electrodes. RFA improved angiographic results immediately after partial coiling (p = 0.0024). Two RFA-related complications occurred, involving transient occlusion of 1 carotid artery and 1 hemorrhage from an adventitial arterial blister. At 12 weeks, angiographic results were improved with RFA (median score of 0), when compared with controls (median score of 2; p = 0.0013). Neointimal closure of the aneurysm neck was better with RFA compared with controls (p = 0.0003). CONCLUSIONS Bipolar RFA can improve results of embolization in experimental models by selectively ablating residual lesions after coil embolization.

Inter- and Intrarater Agreement on the Outcome of Endovascular Treatment of Aneurysms Using MRA

BACKGROUND AND PURPOSE

Patients treated with coiling are often followed by MR angiography. Our objective was to assess the inter- and intraobserver agreement in diagnosing aneurysm remnants and recurrences by using multimodality imaging, including TOF MRA.

MATERIALS AND METHODS

A portfolio composed of 120 selected images from 56 patients was sent to 15 neuroradiologists from 10 institutions. For each case, raters were asked to classify angiographic results (3 classes) of 2 studies (32 MRA-MRA and 24 DSA-MRA pairs) and to provide a final judgment regarding the presence of a recurrence (no, minor, major). Six raters were asked to independently review the portfolio twice. A second study, restricted to 4 raters having full access to all images, was designed to validate the results of the electronic survey.

RESULTS

The proportion of cases judged to have a major recurrence varied between 16.1% and 71.4% (mean, 35.0% ± 12.7%). There was moderate agreement overall (κ = 0.474 ± 0.009), increasing to nearly substantial (κ = 0.581 ± 0.014) when the judgment was dichotomized (presence or absence of a major recurrence). Agreement on cases followed-up by MRA-MRA was similarly substantial (κ = 0.601 ± 0.018). The intrarater agreement varied between fair (κ = 0.257 ± 0.093) and substantial (κ= 0.699 ± 0.084), improving with a dichotomized judgment concerning MRA-MRA comparisons. Agreement was no better when raters had access to all images.

CONCLUSIONS

There is an important variability in the assessment of angiographic outcomes of endovascular treatments. Agreement on the presence of a major recurrence when comparing 2 MRA studies or the MRA with the last catheter angiographic study can be substantial.

Bioactive versus bare platinum coils for the endovascular treatment of intracranial aneurysms: systematic review and meta-analysis of randomized clinical trials

Background

Bioactive coils were introduced in 2002 in an attempt to improve aneurysm healing and durability of angiographic results. Evidence demonstrating superior efficacy to justify the routine use of bioactive coils over bare coils is limited. We compared the periprocedural and clinical outcome after bioactive and bare platinum coiling for intracranial aneurysms.

Methods

MEDLINE, EMBASE, Cochrane Library, and ISI Web of Knowledge Conference Proceedings Citation Index—Science were searched for randomized clinical trials (RCTs) comparing bioactive and bare coils. The methodological quality was evaluated to assess bias risk. Periprocedural outcomes and mid-term outcomes were compared.

Results

Five independent RCTs comparing bioactive (n=1084) and bare coils (n=1084) were identified. Periprocedural outcome was similar for both groups. Bioactive coiling increased the rate of complete aneurysm occlusion (47% vs 40%; RR 1.17 (95% CI 1.05 to 1.31); p=0.006) and reduced the rate of residual aneurysm neck at 10 months compared with bare coiling in the mid-term (26% vs 31%; RR 0.82 (95% CI 0.70 to 0.96); p=0.01). There were no differences in aneurysm recurrence, aneurysm rupture, stroke, neurological death, modified Rankin Scale score and reinterventions. Subgroup analysis for the three RCTs on hydrogel coils demonstrated reduction of residual aneurysms compared with bare coiling (25% vs 34%; RR 0.76 (95% CI 0.58 to 0.99); p=0.04).

Conclusions

Bioactive coils ensure a higher rate of medium-term complete aneurysm occlusion while reducing the rate of residual neck aneurysms compared with bare coiling in the mid-term. Hydrogel coils reduce residual aneurysms compared with bare coils. While there is level 1a evidence to show more complete aneurysm occlusion, longer term follow-up is needed to determine if this translates into clinical significance.

Periprocedural safety of aneurysm embolization with the Medina Coil System: the early human experience

Introduction

Intracranial saccular aneurysms, if untreated, carry a high risk of morbidity and mortality from intracranial bleeding. Embolization coils are the most common treatment. We describe the periprocedural safety and performance of the initial human experience with the next generation Medina Coil System.

Methods

The Medina Coil System is a layered three-dimensional coil made from a radiopaque, shape set core wire, and shape memory alloy outer coil filaments. Nine aneurysms in five patients were selected for treatment with the Medina Coil System.

Results

Nine aneurysms in five patients, ranging from 5 to 17 mm in size in various locations, were treated with the Medina Coil System. No procedural or periprocedural complications were encountered. Procedure times, number of coils used to treat the aneurysm, and use of adjunctive devices were much less than anticipated if conventional coil technology had been used.

Conclusions

The Medina Coil System is a next generation coil that combines all of the familiar and expected procedural safety and technique concepts associated with conventional coils. We found improved circumferential aneurysm filling, which may lead to improved long term outcomes, with fewer devices and faster operating times.

Intra-aneurysmal thrombus modification after flow-diversion

Flow diversion has been successfully used to treat large and giant intracranial aneurysms that present with mass effect. We conducted a retrospective review, evaluating the modification of thrombi in this aneurysm type after treatment with the Pipeline Embolization Device (ev3 Endovascular, Plymouth, MN, USA) and the effects of these modifications on symptoms. Eight patients, seven of whom were female, harbored eight partially thrombosed large or giant aneurysms. Five of the eight aneurysms presented with symptomatic mass effect. At 1 year follow-up, complete occlusion occurred in 75% (6/8) of patients. On average, the longest thrombus diameter measured 22.31 mm before treatment and 14.05 mm 1 year afterwards. Seven of the eight thrombi regressed, as did their aneurysms. All six patients with shrunken thrombi had tremendous symptom improvement and became asymptomatic in the following year. The current findings seem to reflect the size variation of the intra-aneurysmal thrombus rather than the size of the aneurysm itself.

Patients prone to recurrence after endovascular treatment: periprocedural results of the PRET randomized trial on large and recurrent aneurysms

BACKGROUND AND PURPOSE

Some patients with large or recurrent aneurysms may be at increased risk of recurrence postcoiling. The Patients Prone to Recurrence after Endovascular Treatment (PRET) trial was designed to assess whether hydrogel coils were superior to platinum coils in these high-risk patients. This article reports periprocedural safety and operator-assessed angiographic results from the PRET trial.

MATERIALS AND METHODS

PRET was a pragmatic, multicenter, randomized controlled trial. Patients had ≥10-mm aneurysms (PRET-1) or a major recurrence after coiling of an aneurysm of any size (PRET-2). Patients were randomly allocated to hydrogel or control arms (any platinum coil) by using concealed allocation with minimization. Assist devices could be used as clinically required. Aneurysms could be unruptured or recently ruptured. Analyses were on an intent-to-treat basis.

RESULTS

Four hundred forty-seven patients were recruited (250 PRET-1; 197 PRET-2). Aneurysms were recently ruptured in 29% of PRET-1 and 4% of PRET-2 patients. Aneurysms were ≥10 mm in all PRET-1 and in 50% of PRET-2 patients. They were wide-neck (≥4 mm) in 70% and in the posterior circulation in 24% of patients. Stents were used in 28% of patients (35% in PRET-2). Coiling was successful in 98%. Adverse events occurred in 28 patients with hydrogel and 23 with platinum coils. Mortality (n=2, unrelated to treatment) and morbidity (defined as mRS>2 at 1 month) occurred in 25 patients (5.6%; 12 hydrogel, 13 platinum), related to treatment in 10 (4 hydrogel; 6 platinum) (or 2.3% of 444 treated patients). No difference was seen between hydrogel and platinum for any of the indices used to assess safety up to at least 30 days after treatment. At 1 month, 95% of patients were home with a good outcome (mRS≤2 or unchanged). Operator-assessed angiographic outcomes were satisfactory (complete occlusion or residual neck) in 339 of 447 or 76.4% of patients, with no significant difference between groups.

CONCLUSIONS

Endovascular treatment of large and recurrent aneurysms can be performed safely with platinum or hydrogel coils.

Effects of circle of Willis anatomic variations on angiographic and clinical outcomes of coiled anterior communicating artery aneurysms

BACKGROUND AND PURPOSE

Anterior communicating artery aneurysms account for one-fourth of all intracranial aneurysms and frequently occur in the context of A1 vessel asymmetry. The purpose of this study was to correlate circle of Willis anatomic variation association to angiographic and clinical outcomes of anterior communicating aneurysm coiling.

MATERIALS AND METHODS

The Cerecyte Coil Trial provides a subgroup of 124 cases with anterior communicating artery aneurysms after endovascular coiling. One hundred seventeen of 124 anterior communicating artery aneurysms had complete imaging and follow-up for clinical outcome analysis, stability of aneurysm coil packing, and follow-up imaging between 5 and 7 months after treatment. Clinical outcomes were assessed by the mRS at 6 months.

RESULTS

Anterior cerebral artery trunk-dominance was seen in 91 of 124 (73%) anterior communicating artery aneurysms and codominance in 33 of 124 (27%) anterior communicating artery aneurysms. There was no significant difference (P > .5) in treatment success at 5-7 months for anterior communicating artery aneurysms between the anterior cerebral artery trunk-dominant (49 of 86, 57%) and anterior cerebral artery trunk-codominant (19 of 31) groups. Angiographic follow-up demonstrates a statistically significant increase in neck remnants and progressive aneurysm sac filling with the A1 dominant configuration (n = 21, 24% at follow-up versus n = 11, 12% at immediate posttreatment, P = .035). There was no statistically significant difference in clinical outcomes between types of anterior cerebral artery trunk configuration (P > .5).

CONCLUSIONS

Anterior communicating artery aneurysms with anterior cerebral artery trunk-dominant circle of Willis configurations show less angiographic stability at follow-up than those with anterior cerebral artery trunk-codominance similar to other "termination" type aneurysms. This supports the hypothesis that anterior cerebral artery trunk-dominant flow contributes to aneurysm formation, growth, and instability after coiling treatment.

Enhancing brain lesions after endovascular treatment of aneurysms

Complications of endovascular therapy of aneurysms mainly include aneurysm rupture and thromboembolic events. The widespread use of MR imaging for follow-up of these patients revealed various nonvascular complications such as aseptic meningitis, hydrocephalus, and perianeurysmal brain edema. We present 7 patients from 5 different institutions that developed MR imaging-enhancing brain lesions after endovascular therapy of aneurysms, detected after a median time of 63 days. The number of lesions ranged from 4-46 (median of 10.5), sized 2-20 mm, and were mostly in the same vascular territory used for access. Three patients presented with symptoms attributable to these lesions. After a median follow-up of 21.5 months, the number of lesions increased in 2, was stable in 1, decreased in 3, and disappeared in 1. The imaging and clinical characteristics suggested a foreign body reaction. We could find no correlation to a specific device, but a possible source may be the generic hydrophilic coating.

In vivo response to an implanted shape memory polyurethane foam in a porcine aneurysm model

Cerebral aneurysms treated by traditional endovascular methods using platinum coils have a tendency to be unstable, either due to chronic inflammation, compaction of coils, or growth of the aneurysm. We propose to use alternate filling methods for the treatment of intracranial aneurysms using polyurethane-based shape memory polymer (SMP) foams. SMP polyurethane foams were surgically implanted in a porcine aneurysm model to determine biocompatibility, localized thrombogenicity, and their ability to serve as a stable filler material within an aneurysm. The degree of healing was evaluated via gross observation, histopathology, and low vacuum scanning electron microscopy imaging after 0, 30, and 90 days. Clotting was initiated within the SMP foam at time 0 (<1 h exposure to blood before euthanization), partial healing was observed at 30 days, and almost complete healing had occurred at 90 days in vivo, with minimal inflammatory response.

Bioactive versus bare platinum coils in the treatment of intracranial aneurysms: the MAPS (Matrix and Platinum Science) trial

BACKGROUND AND PURPOSE

The ability of polymer-modified coils to promote stable aneurysm occlusion after endovascular treatment is not well-documented. Angiographic aneurysm recurrence is widely used as a surrogate for treatment failure, but studies documenting the correlation of angiographic recurrence with clinical failure are limited. This trial compares the effectiveness of Matrix(2) polyglycolic/polylactic acid biopolymer-modified coils with bare metal coils and correlates the angiographic findings with clinical failure (ie, target aneurysm recurrence), a composite end point that includes any incident of posttreatment aneurysm rupture, retreatment, or unexplained death.

MATERIALS AND METHODS

This was a multicenter randomized noninferiority trial with blinded end point adjudication. We enrolled 626 patients, divided between Matrix(2) and bare metal coil groups. The primary outcome was target aneurysm recurrence at 12 ± 3 months.

RESULTS

At 455 days, at least 1 target aneurysm recurrence event had occurred in 14.6% of patients treated with bare metal coils and 13.3% of Matrix(2) (P = .76, log-rank test) patients; 92.8% of target aneurysm recurrence events were re-interventions for aneurysms that had not bled after treatment, and 5.8% of target aneurysm recurrence events resulted from hemorrhage or rehemorrhage, with or without retreatment. Symptomatic re-intervention occurred in only 4 (0.6%) patients. At 455 days, 95.8% of patients with unruptured aneurysms and 90.4% of those with ruptured aneurysms were independent (mRS ≤ 2). Target aneurysm recurrence was associated with incomplete initial angiographic aneurysm obliteration, presentation with rupture, and a larger aneurysmal dome and neck size.

CONCLUSIONS

Tested Matrix(2) coils were not inferior to bare metal coils. Endovascular coiling of intracranial aneurysms was safe, and the rate of technical success was high. Target aneurysm recurrence is a promising clinical outcome measure that correlates well with established angiographic measurements.

Endovascular treatment of 404 intracranial aneurysms treated with nexus detachable coils: short-term and mid-term results from a prospective, consecutive, European multicenter study

BACKGROUND

Aneurysm recanalization remains a limitation of endovascular treatment. A new type of bioactive coil, the polyglycolic/polylactic acid-covered platinum microfilaments Nexus coil (ev3/Covidien, Irvine, CA, USA), has been proposed. The objective is to evaluate the safety and short-term and mid-term efficacy of Nexus coils in the endovascular treatment of intracranial aneurysms.

METHODS

The ENDECOR (European Nexus Detachable Coil Registry) is the first prospective, consecutive, multicenter non-randomized registry. After providing informed consent, 390 patients (238 women and 152 men; mean age, 51.6 years) with 404 ruptured or unruptured aneurysms were enrolled at 34 centers. Treatment was performed with at least 75 % of coil length as Nexus coils. Clinical and technical complications were systematically reported. An independent core laboratory evaluated angiographic results by using the Raymond Grading Scale.

RESULTS

Complete occlusion was seen in 181 aneurysms (48 %); neck remnant in 86 aneurysms (22 %) and aneurysm remnant in 111 aneurysms (30 %). Technical and clinical complications related to the procedure occurred in 33 patients (8.5 %). At discharge, overall mortality and permanent-morbidity were 4.1 % (16/390) and 5.6 % (14/251), respectively. Angiographic mean follow-up of 13.3 months was obtained in 233 of 390 patients (64.4 %) harboring 247 aneurysms. Recanalization was observed in 44 aneurysms (17.7 %), and progressive thrombosis was observed in 53 aneurysms (21.6 %).

CONCLUSIONS

Endovascular treatment of intracranial aneurysms with Nexus coils was associated with low morbidity and mortality rates. Efficacy of Nexus coils was comparable to published series of intracranial aneurysms treated with bare platinum coils, but their efficacy to prevent aneurysm recanalization was not demonstrated.

Flow-diversion panacea or poison?

Endovascular therapy is now the treatment of choice for intracranial aneurysms (IAs) for its efficacy and safety profile. The use of flow diversion (FD) has recently expanded to cover many types of IAs in various locations. Some institutions even attempt FD as first line treatment for unruptured IAs. The most widely used devices are the pipeline embolization device (PED), the SILK flow diverter (SFD), the flow redirection endoluminal device (FRED), and Surpass. Many questions were raised regarding the long-term complications, the optimal regimen of dual antiplatelet therapy, and the durability of treatment effect. We reviewed the literature to address these questions as well as other concerns on FD when treating IAs.

Advances in Endovascular Approaches to Cerebral Aneurysms

Recent advancements in all phases of endovascular aneurysm treatment, including medical therapy, diagnostics, devices, and implants, abound. Advancements in endovascular technologies and techniques have enabled treatment of a wide variety of intracranial aneurysms. In this article, technical advances in endovascular treatment of cerebral aneurysms are discussed, with an effort to incorporate a clinically relevant perspective. Advancements in diagnostic tools, medical therapy, and implants are reviewed and discussed.

Endovascular methods for the treatment of intracranial cerebral aneurysms

This article briefly discusses the clinical features, natural history, and epidemiology of intracranial cerebral aneurysms, along with current diagnostic imaging techniques for their detection. The main focus is on the basic techniques used in endovascular coiling of ruptured and nonruptured saccular intracranial cerebral aneurysms. After a discussion of each technique, a short review of the results of each form of treatment is given, concentrating on reported large case series. Specific complications related to the endovascular treatment of saccular intracranial aneurysms are then discussed.

Endovascular Therapy for Asymptomatic Unruptured Intracranial Aneurysms

Background and Purpose—

National registration studies (the Japanese Registry of Neuroendovascular Therapy [JR-NET] and JR-NET2) have determined the current status and outcomes of neuroendovascular therapy (neuro-EVT). We analyzed short-term outcomes of EVT for asymptomatic unruptured intracranial aneurysms (UIAs).

Methods—

We extracted periprocedural information about EVT for 4767 asymptomatic UIAs from 31 968 registered procedural records of all EVT in the JR-NET and JR-NET2 databases. We assessed the features of the aneurysms and procedures, immediate radiographic findings, procedure-related complications, and clinical outcomes at 30 days after the procedures.

Results—

We located 80.0% of UIAs in the anterior circulation, and the most frequent were paraclinoid. The diameter of 2.5%, 32.9%, 51.9%, 12.0%, and 0.7% of the UIAs was <3, 3 to 4, 5 to 9, 10 to 19, and >20 mm, respectively. EVT failed in only 2.1%. Adjunctive techniques were applied in 54.8% of procedures. Pre- and postprocedural antiplatelet agents were prescribed in 85.6% and 84.0%, respectively, of the procedures. The immediate radiographic outcomes of 57.7%, 31.9%, and 10.0% of the UIAs comprised complete occlusion, residual necks, and residual aneurysms, respectively. Complications that were associated with 9.1% of procedures comprised 2.0% hemorrhagic and 4.6% ischemic, and the 30-day morbidity and mortality rates were 2.12% and 0.31%, respectively.

Conclusions—

The radiographic results of EVT for asymptomatic UIAs in Japan were acceptable, with low mortality and morbidity rates.

Comparative effectiveness of ruptured cerebral aneurysm therapies: propensity score analysis of clipping versus coiling

BACKGROUND AND PURPOSE

The relative merits of treating ruptured aneurysms with clipping versus coiling continue to be a topic of debate. We evaluated a national, multihospital patient data base to examine recent trends in ruptured aneurysm therapies and to compare peri-procedural outcomes between clipping and coiling treatments.

MATERIALS AND METHODS

The Premier Perspective data base was used to identify patients hospitalized between 2006-2011 for ruptured aneurysm who underwent clipping or coiling therapy. A propensity score model, representing the probability of receiving clipping, was generated for each patient by use of relevant patient and hospital variables. After Greedy-type matching of the propensity score, the risk of in-hospital mortality and morbidity was compared between clipping and coiling cohorts.

RESULTS

A total of 5229 patients with ruptured aneurysm (1228 clipping, 4001 coiling) treated at 125 hospitals were identified. Clipping therapy frequency decreased from 27% in 2006 to 21% in 2011. After propensity score adjustment, in-hospital mortality risk was similar between groups (OR = 0.94 [95% CI, 0.73-1.21]; P = .62). However, unfavorable outcomes were more common after clipping compared with coiling, including discharge to long-term care (OR = 1.32 [95% CI, 1.12-1.56]; P = .0006), ischemic complications (OR = 1.51 [95% CI, 1.24-1.83]; P = .0009), neurologic complications (OR = 1.64 [95% CI, 1.18-2.27]; P = .0018), and other surgical complications (OR = 1.55 [95% CI, 1.05-2.33]; P = .0240).

CONCLUSIONS

This study of a data base of multiple hospitals in the United States demonstrates that clipping of ruptured cerebral aneurysms resulted in greater adjusted morbidity compared with coiling.

Differences in the angiographic evaluation of coiled cerebral aneurysms between a core laboratory reader and operators: results of the Cerecyte Coil Trial

BACKGROUND AND PURPOSE

Independent evaluation of angiographic images is becoming widely applied in the assessment of treatment outcomes of cerebral aneurysms. In the current study, we assessed the agreement between an independent core laboratory and the operators regarding angiographic appearance in a recent randomized, controlled trial.

MATERIALS AND METHODS

Data were derived from the Cerecyte Coil Trial. Angiographic images of each coiled aneurysm, taken immediately after embolization and at 5- to 7-month follow-up, were evaluated by the operator at the treating center and by an independent neuroradiologist at the core laboratory. For the purpose of this study, images were interpreted on a 3-point scale to provide uniformity for analysis; grade 1: complete occlusion, grade 2: neck remnant; and grade 3: sac filling. "Unfavorable angiographic appearance" was defined as grade 3 at follow-up or interval worsening of grade between the 2 time points.

RESULTS

The study included 434 aneurysms. Immediately after embolization, grade 3 was reported by operators in 39 (9%) compared with 52 (12%) by the core laboratory (P = .159). On follow-up, grade 3 was reported by operators in 44 (10%) compared with 81 (19%) by the core laboratory (P < .0001). Overall, operators noted unfavorable angiographic appearance in 78 (18%) compared with 134 (31%) by the core laboratory (P < .0001). At every time point, agreement between the core laboratory and the operators was slight.

CONCLUSIONS

Unfavorable angiographic appearance was noted almost twice as frequently by an independent core laboratory as compared with the operators. Planning of trials and interpretation of published studies should be done with careful attention to the mode of angiographic appearance interpretation.

Coil embolization versus clipping for ruptured intracranial aneurysms: a meta-analysis of prospective controlled published studies

BACKGROUND AND PURPOSE

Coil embolization is an alternative to clipping for intracranial aneurysms. However, controversy exists regarding the best therapeutic strategy in patients with ruptured aneurysms, and there is great center- and country-related variability in the rates of clipping versus coiling. We performed a meta-analysis of prospective controlled trials of clipping versus coil embolization for ruptured aneurysms.

MATERIALS AND METHODS

We performed a search of the English literature for published prospective controlled trials comparing surgical clipping with endovascular coil embolization for ruptured intracranial aneurysms. Data were abstracted from the identified references. Outcomes of interest were the proportion of patients with a poor outcome at 1 year and episodes of rebleeding from the index treated aneurysm after the allocated treatment.

RESULTS

There were 3 prospective controlled trials eligible for inclusion. These studies enrolled 2723 patients. Meta-analysis of these studies showed that the rate of poor outcome at 1 year was significantly lower in patients allocated to coil embolization (risk ratio, 0.75; 95% confidence interval, 0.65-0.87). This relative effect is consistent with an absolute risk reduction of 7.8% and a number needed to treat of 13. The effect on mortality was not statistically different across the 2 treatments. Rebleeding rates within the first month were higher in patients allocated to endovascular coil embolization.

CONCLUSIONS

On the basis of the analysis of the 3 high-quality prospective controlled trials available, there is strong evidence to indicate that endovascular coil embolization is associated with better outcomes compared with surgical clipping in patients amenable to either therapeutic strategy.

Safety and efficacy of neuroform for treatment of intracranial aneurysms: a prospective, consecutive, French multicentric study

BACKGROUND AND PURPOSE

Endovascular embolization of wide-neck intracranial aneurysms can be technically challenging, especially when the anatomy is complex. Stent reconstruction of the parent artery is commonly used to treat wide-neck and bifurcated aneurysms. The main objective of this study was to investigate the periprocedural and midterm morbidity and mortality results of this procedure.

MATERIALS AND METHODS

SENAT is a consecutive, prospective, multicentric study. Patients with unruptured cerebral aneurysms who underwent endovascular treatment with the Neuroform stent system were recruited and recorded. Technical outcomes and complications were also assessed. The midterm anatomic results were re-evaluated at 12-18 months.

RESULTS

A total of 113 stents were used to treat the 107 aneurysms in 107 patients. The mean width of the aneurysm sac was 6.2 mm, and the mean diameter of aneurysm neck was 4.5 mm. The complete occlusion rate postprocedure was 66.4%. The rate of progressive occlusion at 12-18 months was 14%, and the rate of recurrence was 9.7%. The rate of subsequent treatment was 4%. The thromboembolic rate in the periprocedural period was 3.7%, and the rate of delayed TE events was 3%. Overall, the mortality rate at 12-18 months was 1%, and the permanent morbidity rate was 1%.

CONCLUSIONS

Stent-assisted coiling with the Neuroform stent system provides a high level of occlusion with low rates of subsequent treatment despite a predominant population of patients with wide-neck aneurysms. Morbidity and thromboembolic rates were comparable to studies investigating stand-alone coiling.