Search

Background and purpose Previous studies suggest that mechanisms and outcomes in patients with COVID-19-associated stroke differ from those in patients with non-COVID-19-associated strokes, but there is limited comparative evidence focusing on these populations. The aim of this study, therefore, was to determine if a significant association exists between COVID-19 status with revascularization and functional outcomes following thrombectomy for large vessel occlusion (LVO), after adjustment for potential confounding factors. Methods A cross-sectional, international multicenter retrospective study was conducted in consecutively admitted COVID-19 patients with concomitant acute LVO, compared to a control group without COVID-19. Data collected included age, gender, comorbidities, clinical characteristics, details of the involved vessels, procedural technique, and various outcomes. A multivariable-adjusted analysis was conducted. Results In this cohort of 697 patients with acute LVO, 302 had COVID-19 while 395 patients did not. There was a significant difference (p < 0.001) in the mean age (in years) and gender of patients, with younger patients and more males in the COVID-19 group. In terms of favorable revascularization (modified Thrombolysis in Cerebral Infarction [mTICI] grade 3), COVID-19 was associated with lower odds of complete revascularization (odds ratio 0.33, 95% confidence interval [CI] 0.23-0.48; p < 0.001), which persisted on multivariable modeling with adjustment for other predictors (adjusted odds ratio 0.30, 95% CI 0.12-0.77; p = 0.012). Moreover, endovascular complications, in-hospital mortality, and length of hospital stay were significantly higher among COVID-19 patients (p < 0.001). Conclusion COVID-19 was an independent predictor of incomplete revascularization and poor functional outcome in patients with stroke due to LVO. Furthermore, COVID-19 patients with LVO were more often younger and had higher morbidity/mortality rates.

Treatment of small-caliber vessel lesions using flow diverters remains challenging because of vasculature's narrow luminal diameter and tortuosity. This in turn makes navigation and delivery of conventional devices with standard microcatheters more difficult. The Silk Vista Baby (SVB, Balt) flow diversion device was designed for ease of use in vessels with a smaller diameter, distal lesions, and 0.017 ″ microcatheter delivery systems.To report the outcomes of the SVB device on the treatment of posterior inferior cerebellar artery (PICA) aneurysms.Databases from different centers were retrospectively reviewed for PICA aneurysms treated with SVB. Demographic information, clinical presentation, radiographic characteristics, procedural complications, and immediate postprocedure outcomes were obtained.Fourteen patients harboring 15 true PICA aneurysms were treated between January 2019 and June 2021. Nine were female (n = 9/14; 64.2%), and the mean age was 51 ± 14.9 years. Most patients had previously ruptured aneurysms, treated by another endovascular technique. Six aneurysms were located distally (n = 6/15; 40%). The mean neck size was 3 mm (SD 1.35, range 2.5-5 mm), whereas the mean PICA diameter was 1.6 mm (SD 0.26, range 1.5-1.7 mm). The mean length of follow-up was 6 months (SD 8.28, range 4.5-16 months). Treatment-related adverse events included 1 case of transient hypoesthesia. Two additional events were reported, but adjudicated as unrelated to the procedure. Complete occlusion, measured as Raymond-Roy class I, was achieved in all cases.The SVB device was safely and effectively used in the treatment of PICA aneurysms. The smaller delivery system profile reduces the risk of procedure complications and creates new treatment options for distal lesions.

BackgroundIn contrast to conventional CT perfusion (CTP) imaging, flat panel detector CT perfusion (FD-CTP) imaging can be acquired directly in the angiosuite.ObjectiveTo evaluate time-resolved whole brain FD-CTP imaging and assess clinically important qualitative and quantitative perfusion parameters in correlation with previously acquired conventional CTP using the new RAPID for ANGIO software.MethodsWe included patients with internal carotid artery occlusions and M1 or M2 occlusions from six centers. All patients underwent mechanical thrombectomy (MT) with preinterventional conventional CTP and FD-CTP imaging. Quantitative performance was determined by comparing volumes of infarct core, penumbral tissue, and mismatch. Eligibility for MT according to the perfusion imaging criteria of DEFUSE 3 was determined for each case from both conventional CTP and FD-CTP imaging.ResultsA total of 20 patients were included in the final analysis. Conventional relative cerebral blood flow (rCBF) 2=0.84). Comparisons of conventional CTP Tmax >6 s versus FD-CTP Tmax >6 s and CTP mismatch versus FD-CTP mismatch showed more variability (R2=0.57, and R2=0.33, respectively). Based on FD-CTP, 16/20 (80%) patients met the inclusion criteria for MT according to the DEFUSE 3 perfusion criteria, in contrast to 18/20 (90%) patients based on conventional CTP. The vessel occlusion could be correctly extrapolated from the hypoperfusion in 18/20 cases (90%).ConclusionsIn our multicenter study, time-resolved whole brain FD-CTP was technically feasible, and qualitative and quantitative perfusion results correlated with those obtained with conventional CTP.

BackgroundFlow diverters have revolutionized the treatment of intracranial aneurysms. Nevertheless, some aneurysms fail to occlude with flow diversion. The Prospective Study on Embolization of Intracranial Aneurysms with the Pipeline Device (PREMIER) was a prospective, multicenter and single-arm trial of small and medium wide-necked unruptured aneurysms. In the current study, we evaluate the predictors of treatment failure in the PREMIER cohort.MethodsWe analyzed PREMIER patients who had incomplete occlusion (Raymond-Roy >1) at 1 year angiographic follow-up and compared them with those who achieved Raymond-Roy 1, aiming to identify predictors of treatment failure.Results25 aneurysms demonstrated incomplete occlusion at 1 year. There was a median reduction of 0.9 mm (IQR 0.41–2.43) in maximum diameter between pre-procedure and 1 year measurements, with no aneurysmal hemorrhage. Patients with incomplete occlusion were significantly older than those with complete occlusion (p=0.011). Smoking (p=0.045) and C6 segment location (p=0.005) were significantly associated with complete occlusion, while location at V4 (p=0.01) and C7 (p=0.007) and involvement of a side branch (pConclusionsThe results of our study are consistent with previous retrospective series and warrant consideration for technique adaptations to achieve higher occlusion rates. Further follow-up is needed to assess progression of aneurysm occlusion and clinical behavior in these cases.

BackgroundThe mechanisms and outcomes in coronavirus disease (COVID-19)-associated stroke are unique from those of non-COVID-19 stroke.ObjectiveTo describe the efficacy and outcomes of acute revascularization of large vessel occlusion (LVO) in the setting of COVID-19 in an international cohort.MethodsWe conducted an international multicenter retrospective study of consecutively admitted patients with COVID-19 with concomitant acute LVO across 50 comprehensive stroke centers. Our control group constituted historical controls of patients presenting with LVO and receiving a mechanical thrombectomy between January 2018 and December 2020.ResultsThe total cohort was 575 patients with acute LVO; 194 patients had COVID-19 while 381 patients did not. Patients in the COVID-19 group were younger (62.5 vs 71.2; P < .001) and lacked vascular risk factors (49, 25.3% vs 54, 14.2%; P = .001). Modified thrombolysis in cerebral infarction 3 revascularization was less common in the COVID-19 group (74, 39.2% vs 252, 67.2%; P < .001). Poor functional outcome at discharge (defined as modified Ranklin Scale 3-6) was more common in the COVID-19 group (150, 79.8% vs 132, 66.7%; P = .004). COVID-19 was independently associated with a lower likelihood of achieving modified thrombolysis in cerebral infarction 3 (odds ratio [OR]: 0.4, 95% CI: 0.2-0.7; P < .001) and unfavorable outcomes (OR: 2.5, 95% CI: 1.4-4.5; P = .002).ConclusionCOVID-19 was an independent predictor of incomplete revascularization and poor outcomes in patients with stroke due to LVO. Patients with COVID-19 with LVO were younger, had fewer cerebrovascular risk factors, and suffered from higher morbidity/mortality rates.

BackgroundStent-assisted coiling of wide-necked intracranial aneurysms (IAs) using the Neuroform Atlas Stent System (Atlas) has shown promising results.ObjectiveTo present the primary efficacy and safety results of the ATLAS Investigational Device Exemption (IDE) trial in a cohort of patients with posterior circulation IAs.MethodsThe ATLAS trial is a prospective, multicenter, single-arm, open-label study of unruptured, wide-necked, IAs treated with the Atlas stent and adjunctive coiling. This study reports the results of patients with posterior circulation IAs. The primary efficacy endpoint was complete aneurysm occlusion (Raymond-Roy (RR) class I) on 12-month angiography, in the absence of re-treatment or parent artery stenosis >50%. The primary safety endpoint was any major ipsilateral stroke or neurological death within 12 months. Adjudication of the primary endpoints was performed by an imaging core laboratory and a Clinical Events Committee.ResultsThe ATLAS trial enrolled and treated 116 patients at 25 medical centers with unruptured, wide-necked, posterior circulation IAs (mean age 60.2±10.5 years, 81.0% (94/116) female). Stents were placed in all patients with 100% technical success rate. A total of 95/116 (81.9%) patients had complete angiographic follow-up at 12 months, of whom 81 (85.3%) had complete aneurysm occlusion (RR class I). The primary effectiveness outcome was achieved in 76.7% (95% CI 67.0% to 86.5%) of patients. Overall, major ipsilateral stroke and secondary persistent neurological deficit occurred in 4.3% (5/116) and 1.7% (2/116) of patients, respectively.ConclusionsIn the ATLAS IDE posterior circulation cohort, the Neuroform Atlas Stent System with adjunctive coiling demonstrated high rates of technical and safety performance.Trial registration numberhttps://clinicaltrials.gov/ct2/show/NCT02340585.

Background Intravascular ultrasound (IVUS) provides endoluminal views and cross-sectional images of carotid arteries but lacks overview of vascular territory provided by angiography. Co-registration of IVUS with angiographic images may provide the potential to navigate both imaging modalities in a synchronous manner. The objective of this study is to evaluate the feasibility and accuracy of co-registering both imaging modalities in the carotid vasculature of the neck. Methods Fourteen patients with 15 cervical carotid artery lesions underwent angiography and subsequent treatment. In each case, an IVUS catheter was advanced to the target lesion and a reference angiography sequence was acquired. This was followed by an electrocardiography-triggered fluoroscopy sequence that was initiated upon IVUS catheter pullback. IVUS data collected during pullback were registered with fluoroscopy and evaluated for error and clinical usability. Results A total of 32 landmarks were identified that demonstrated reasonable agreement during IVUS–angiography co-registration. There was a mean registration error distance of 3.36 mm (SD 2.82 mm) between targets. The longitudinal extent and severity of the disease through the target segment could be easily evaluated after co-registration. Conclusion Semiautomatic tracking and co-registration of angiography and IVUS is a new technology and has the potential to increase the use of IVUS in carotid disease and to proivde the opportunity to optimize procedural outcomes.

Background Preventing errors and complications in neurointervention is crucial, particularly in the treatment of unruptured intracranial aneurysms (UIAs), where the natural history is generally benign, and the margin of treatment benefit small. We aimed to investigate how neurointerventionalists perceive the importance and frequency of errors and the resulting complications in endovascular UIA treatment, and which steps could be taken to prevent them. Methods An international multidisciplinary survey was conducted among neurointerventionalists. Participants provided their demographic characteristics and neurointerventional treatment volume. They were asked about their perceptions on the importance and frequency of different errors in endovascular UIA treatment, and which solutions they thought to be most effective in preventing these errors. Results Two-hundred-thirty-three neurointerventionalists from 38 countries participated in the survey. Participants identified errors in technical execution as the most common source of complications in endovascular UIA treatment (40.4% thought these errors constituted a relatively or very large proportion of all complication sources), closely followed by errors in decision-making/indication (32.2%) and errors related to management of unexpected events (28.4%). Simulation training was thought to be most effective in reducing technical errors, while cognitive errors were believed to be best minimized by abandoning challenging procedures, more honest discussion of complications and better standardization of procedure steps. Conclusion Neurointerventionalists perceived both technical and cognitive errors to be important sources of complications in endovascular UIA treatment. Simulation training, a cultural change, higher acceptance of bail-out strategies and better standardization of procedures were perceived to be most effective in preventing these.

Intravascular imaging has emerged as a valuable tool for the treatment of coronary and peripheral artery disease; however, no solution is available for safe and reliable use in the tortuous vascular anatomy of the brain. Endovascular treatment of stroke is delivered under image guidance with insufficient resolution to adequately assess underlying arterial pathology and therapeutic devices. High-resolution imaging, enabling surgeons to visualize cerebral arteries' microstructure and micron-level features of neurovascular devices, would have a profound impact in the research, diagnosis, and treatment of cerebrovascular diseases. Here, we present a neurovascular high-frequency optical coherence tomography (HF-OCT) system, including an imaging console and an endoscopic probe designed to rapidly acquire volumetric microscopy data at a resolution approaching 10 microns in tortuous cerebrovascular anatomies. Using a combination of in vitro, ex vivo, and in vivo models, the feasibility of HF-OCT for cerebrovascular imaging was demonstrated., High resolution intravascular imaging in the brain is limited by the high tortuosity of the vasculature. Here the authors present a fiber optic imaging technology using high-frequency optical coherence tomography (HF-OCT) to provide volumetric high resolution images in the highly tortuous cerebral vasculature.

Objective Endovascular treatment of carotid-cavernous fistulas (CCFs) has been consistently shown to give excellent results and is currently the mainstay of treatment of these complex vascular pathologies. Onyx is currently the most widely used agent, but there has been concern over high rates of cranial nerve (CN) deficits seen in patients with CCF treated with Onyx and paucity of data on long-term outcomes. Methods This is a retrospective analysis of patients who underwent transvenous Onyx embolization between 2011 and 2018. The data collected included demographics, comorbidities, presenting symptoms, CCF morphology, degree of obliteration, procedure-related complications, clinical outcomes, and follow-up. Results A total of seven patients (five females) were included. The median age was 66 years (range: 15–79 years). Median duration of symptoms before treatment was 4 weeks (range: 1–24 weeks). There were three direct and four indirect CCFs. Barrow classification is as follows: A-3; B-3; C-0; and D-1. Immediate complete occlusion was achieved in all cases. There was also one case of immediate postoperative change in CN function (new partial CN VI deficit) that resolved completely at 1-month follow-up. The mean length of stay was 3 days (±2). The preoperative extraocular movement CN deficits had the following outcomes: three resolved; two improved; and one persisted. Proptosis, chemosis, conjunctival injection, and tinnitus were resolved in all patients. The median follow-up was 34 months (range: 10–91 months). Conclusion Transvenous Onyx embolization is a safe and effective treatment of CCFs when technical aspects to reduce complications are performed diligently. Our technique demonstrates safety of the Onyx as a stand-alone embolization for the treatment of CCF.

Final lesion volume (FLV) is a surrogate outcome measure in anterior circulation stroke (ACS). In posterior circulation stroke (PCS), this relation is plausibly understudied due to a lack of methods that automatically quantify FLV. The applicability of deep learning approaches to PCS is limited due to its lower incidence compared to ACS. We evaluated strategies to develop a convolutional neural network (CNN) for PCS lesion segmentation by using image data from both ACS and PCS patients. We included follow-up non-contrast computed tomography scans of 1018 patients with ACS and 107 patients with PCS. To assess whether an ACS lesion segmentation generalizes to PCS, a CNN was trained on ACS data (ACS-CNN). Second, to evaluate the performance of only including PCS patients, a CNN was trained on PCS data. Third, to evaluate the performance when combining the datasets, a CNN was trained on both datasets. Finally, to evaluate the performance of transfer learning, the ACS-CNN was fine-tuned using PCS patients. The transfer learning strategy outperformed the other strategies in volume agreement with an intra-class correlation of 0.88 (95% CI: 0.83–0.92) vs. 0.55 to 0.83 and a lesion detection rate of 87% vs. 41–77 for the other strategies. Hence, transfer learning improved the FLV quantification and detection rate of PCS lesions compared to the other strategies.

BackgroundPreliminary clinical studies on the safety and efficacy of the pipeline embolization device (PED) for the treatment of small/medium aneurysms have demonstrated high occlusion rates with low complications.ObjectiveTo evaluate the safety and effectiveness of the PED for treatment of wide necked small and medium intracranial aneurysms.MethodsPREMIER is a prospective, multicenter, single arm trial. Patients were treated with the PED for unruptured wide necked aneurysms, measuring ≤12 mm along the internal carotid artery or vertebral artery, between July 2014 and November 2015. At 1 year post-procedure, the primary effectiveness endpoint was complete occlusion (Raymond grade 1) without major parent vessel stenosis (≤50%) or retreatment, and the primary safety endpoint was major stroke in the territory supplied by the treated artery or neurologic death.ResultsA total of 141 patients were treated with PEDs (mean age 54.6±11.3 years, 87.9% (124/141) women). Mean aneurysm size was 5.0±1.92 mm, and 84.4% (119/141) measured ConclusionsTreatment of wide necked small/medium aneurysms with the PED results in high rates of complete occlusion without significant parent vessel stenosis and low rates of permanent neurologic complications.Trial registrationNCT02186561.

Background and Purpose— Hyperglycemia is a negative prognostic factor after acute ischemic stroke but is not known whether glucose is associated with the effects of endovascular thrombectomy (EVT) in patients with large-vessel stroke. In a pooled-data meta-analysis, we analyzed whether serum glucose is a treatment modifier of the efficacy of EVT in acute stroke. Methods— Seven randomized trials compared EVT with standard care between 2010 and 2017 (HERMES Collaboration [highly effective reperfusion using multiple endovascular devices]). One thousand seven hundred and sixty-four patients with large-vessel stroke were allocated to EVT (n=871) or standard care (n=893). Measurements included blood glucose on admission and functional outcome (modified Rankin Scale range, 0–6; lower scores indicating less disability) at 3 months. The primary analysis evaluated whether glucose modified the effect of EVT over standard care on functional outcome, using ordinal logistic regression to test the interaction between treatment and glucose level. Results— Median (interquartile range) serum glucose on admission was 120 (104–140) mg/dL (6.6 mmol/L [5.7–7.7] mmol/L). EVT was better than standard care in the overall pooled-data analysis adjusted common odds ratio (acOR), 2.00 (95% CI, 1.69–2.38); however, lower glucose levels were associated with greater effects of EVT over standard care. The interaction was nonlinear such that significant interactions were found in subgroups of patients split at glucose < or >90 mg/dL (5.0 mmol/L; P =0.019 for interaction; acOR, 3.81; 95% CI, 1.73–8.41 for patients < 90 mg/dL versus 1.83; 95% CI, 1.53–2.19 for patients >90 mg/dL), and glucose < or >100 mg/dL (5.5 mmol/L; P =0.004 for interaction; acOR, 3.17; 95% CI, 2.04–4.93 versus acOR, 1.72; 95% CI, 1.42–2.08) but not between subgroups above these levels of glucose. Conclusions— EVT improved stroke outcomes compared with standard treatment regardless of glucose levels, but the treatment effects were larger at lower glucose levels, with significant interaction effects persisting up to 90 to 100 mg/dL (5.0–5.5 mmol/L). Whether tight control of glucose improves the efficacy of EVT after large-vessel stroke warrants appropriate testing.

International audience; Importance: The positive treatment effect of endovascular therapy (EVT) is assumed to be caused by the preservation of brain tissue. It remains unclear to what extent the treatment-related reduction in follow-up infarct volume (FIV) explains the improved functional outcome after EVT in patients with acute ischemic stroke.Objective: To study whether FIV mediates the relationship between EVT and functional outcome in patients with acute ischemic stroke.Design, setting, and participants: Patient data from 7 randomized multicenter trials were pooled. These trials were conducted between December 2010 and April 2015 and included 1764 patients randomly assigned to receive either EVT or standard care (control). Follow-up infarct volume was assessed on computed tomography or magnetic resonance imaging after stroke onset. Mediation analysis was performed to examine the potential causal chain in which FIV may mediate the relationship between EVT and functional outcome. A total of 1690 patients met the inclusion criteria. Twenty-five additional patients were excluded, resulting in a total of 1665 patients, including 821 (49.3%) in the EVT group and 844 (50.7%) in the control group. Data were analyzed from January to June 2017.Main outcome and measure: The 90-day functional outcome via the modified Rankin Scale (mRS).Results: Among 1665 patients, the median (interquartile range [IQR]) age was 68 (57-76) years, and 781 (46.9%) were female. The median (IQR) time to FIV measurement was 30 (24-237) hours. The median (IQR) FIV was 41 (14-120) mL. Patients in the EVT group had significantly smaller FIVs compared with patients in the control group (median [IQR] FIV, 33 [11-99] vs 51 [18-134] mL; P = .007) and lower mRS scores at 90 days (median [IQR] score, 3 [1-4] vs 4 [2-5]). Follow-up infarct volume was a predictor of functional outcome (adjusted common odds ratio, 0.46; 95% CI, 0.39-0.54; P < .001). Follow-up infarct volume partially mediated the relationship between treatment type with mRS score, as EVT was still significantly associated with functional outcome after adjustment for FIV (adjusted common odds ratio, 2.22; 95% CI, 1.52-3.21; P < .001). Treatment-reduced FIV explained 12% (95% CI, 1-19) of the relationship between EVT and functional outcome.Conclusions and relevance: In this analysis, follow-up infarct volume predicted functional outcome; however, a reduced infarct volume after treatment with EVT only explained 12% of the treatment benefit. Follow-up infarct volume as measured on computed tomography and magnetic resonance imaging is not a valid proxy for estimating treatment effect in phase II and III trials of acute ischemic stroke.

Background: Stent-assisted coiling (SAC) leads to significant changes in the vascular angle altering the bifurcation geometry and the hemodynamics at the bifurcation apex. It is believed that the stent alone exerts this effect, but other possible factors have not been studied. Purpose: To study the factors contributing to angular remodeling following SAC of bifurcation aneurysms including the anatomical, stent-related, and coil-related factors. Materials and Methods: We reviewed 43 basilar and carotid bifurcation aneurysms treated by SAC using Neuroform EZ (n = 28), Enterprise (n = 8), and Lvis Jr. (n = 7) stents. The bifurcation angle between the mother and stented daughter vessel was measured in 4 settings: pretreatment, poststenting, postcoiling, and at delayed follow-up (6–12 months). The degree of stent-induced angular remodeling was calculated by subtracting the poststenting bifurcation angle from the pretreatment one, while the coil-induced angular remodeling was calculated as the difference between the postcoiling and poststenting bifurcation angle. The immediate postprocedural degree of angular remodeling is the sum of the stent- and coil-induced angular remodeling. We studied the effect of several factors including the pretreatment bifurcation angle, aneurysm site, diameter of parent vessel, stent type, stent length in the daughter vessel, postoperative actual in situ coil size, and packing density. Results: The mean degree of stent-induced and coil-induced angular remodeling was 10.2 (0–47) and 4.53 (–7 to 30), respectively. The immediate postprocedural and delayed angular remodeling was 14.8 (–4 to 47) and 4.75 (–12 to 40), respectively. The degree of immediate remodeling was significantly affected by the actual in situ coil size (p = 0.017), and the pretreatment bifurcation angle (p = 0.024). Linear regression was carried out and the pretreatment bifurcation angle was defined as a predictor. The degree of delayed remodeling is significantly affected only by the pretreatment bifurcation angle (p = 0.011). Conclusion: Immediate angular remodeling following SAC of bifurcation aneurysms can happen after stenting or coiling or both. This is the first study reporting the role of the coils as an additional factor beside the stent in inducing immediate angular changes; this effect is correlated to the size of the coils. The pretreatment bifurcation angle is the most consistent factor affecting the degree of both immediate and delayed angular remodeling.

The aim of the study is to evaluate the hemodynamic changes and the parenchymal perfusion associated with carotid cavernous fistulas before and after embolization using two-dimensional (2D) parenchymal blood flow analysis. A 15-year-old boy presented with 2-month history of progressive right eye proptosis, chemosis, and diplopia after a motor vehicle accident. Intracranial liquid embolization using Onyx-18 through the inferior petrosal approach was done with balloon protection at the opening of the fistula in the internal carotid artery, resulting in complete occlusion of the fistula. Parenchymal blood flow analysis was done before and immediately after embolization. 2D parametric parenchymal blood flow analysis is newly introduced software that can provide data cannot be conveyed by conventional digital subtraction angiography alone. The software allows for objective assessment of the arterial steal and the parenchymal perfusion both pre, and post-embolization. Pre-embolization assessment may influence the therapeutic decision, while post-embolization assessment can evaluate the treatment efficacy.

Purpose Flow-diverters have revolutionized the endovascular treatment of intracranial aneurysms, offering a durable solution to aneurysms with high recurrence rates after conventional stent-assisted coiling. Events that occur after treatment with flow-diversion, such as in-stent stenosis (ISS) are not well understood and require further assessment. After assessing an animal model with Optical Coherence Tomography (OCT), we propose a concept that could explain the mechanism causing reversible ISS after treatment of intracranial aneurysms with flow-diverters. Methods Six Pipeline Flex embolization devices (PED-Flex), six PED with Shield technology (PED-Shield), and four Solitaire AB devices were implanted in the carotid arteries (two stents per vessel) of four pigs. Intravascular optical coherence tomography (OCT) and digital subtraction angiography (DSA) images obtained on day 21 were compared to histological specimens. Results A case of ISS in a PED-Flex device was assessed with OCT imaging. Neointima with asymmetrical topography completely covering the PED struts was observed. Histological preparations of the stenotic area demonstrated thrombus on the surface of device struts, covered by neointima. Conclusion This study provides a plausible concept for reversible ISS in flow-diverters. Based on an observation of a previous experiment, we propose that similar cases of ISS are related to thrombus presence underneath endothelization, but further experiments focused on this phenomenon are needed. Optical Coherence Tomography will be useful tool when available for clinical use.

Background & Significance: The Covid-19 pandemic has created a host of challenges for healthcare systems and hospital teams that have put unprecedented stress on staff and leaders to re-design care and management of not only the Covid positive patient but also the hospitalized non-Covid patient. As this large healthcare system began to prepare for a Covid surge of patients, stroke program leaders recognized the need for alternative placement and management plans. With the re-designation of units and beds and deployment of staff into non-primary units, program leaders were concerned with not only placement of stroke patients outside of regular stroke and Neurocritical Care Units but also with non-trained stroke nursing staff caring for the patient. In response, this stroke program convened a working group to create alternative guidelines for care of the stroke patient during Covid surge and critical bed shortages. Design & Methods: The need for established criteria to guide all sites in the care of patients post IV thrombolytic or mechanical thrombectomy was the key objective. The alternative guideline was drafted and submitted to the system Covid clinical command center for emergent approval. Once approval given, education was provided to all stroke coordinators and key leaders at each site. To provide full access, guidelines were posted and available on the system SharePoint site for access to all team members. Results: The drafting of alternative stroke guidelines allowed for improved patient safety during our 27-hospital healthcare systems Covid surge. Care of multiple patients occurred outside normal critical care and stroke units with a decreased number of assessments for patients from the standard, pre-Covid and without increase safety events or adverse outcomes. The success of the alternative guidelines and this Covid effect on stroke care management not only helped our staff and patients during a time of need in safe care but also provided a new model of care for our stroke program leaders to consider and implement across our organizations.

Acute carotid terminus occlusion (CTO) is responsible for up to 5% of acute ischemic strokes secondary to emergent large vessel occlusion (ELVO) and up to 20% of acute internal carotid artery (ICA) occlusions.1 The term "CTO" has also been used to describe occlusions in the supra-clinoid segment or at the bifurcation of the ICA. Compared to other ELVOs, patients with CTO present with higher stroke severity and larger infarct volume, likely to be a result of disruption of direct Circle of Willis collaterals across the anterior communicating artery (AComA) and posterior communicating artery (PComA).2,3 Similary, CTO is usually associated with worse prognosis compared to other ELVOs in general. With regard to response to treatment, previous studies have reported significantly lower recanalization rates with intravenous alteplase with CTO compared to M1 segment occlusion. With regard to the safety and efficacy of mechanical thrombectomy, prior reports provide conflicting results with some reporting lower successful recanalization rates with CTO compared to M1 occlusion, and others reporting similar results. In our experience, we have found that successful recanalization of CTO can be achieved with a similar approach to M1 occlusions utilizing a direct aspiration first pass technique (ADAPT).3,4 Herein, we present a case of CTO for which we performed mechanical thrombectomy using ADAPT. This procedure was an emergent standard of care procedure for which a consent was not required and so not obtained.

As capabilities for endovascular treatment of intracranial vascular pathologies continue to expand, the need for access to the distal internal carotid artery with rigid support catheter systems continues to increase. One of the dominant factors limiting this access is patient anatomy, specifically vessel tortuosity. Increased tortuosity of the carotid siphon is a frequently encountered anatomic variant and may complicate endovascular procedures in adults and children.1,2 Failed attempts to navigate the carotid siphon with a distal access catheter carry a risk of vessel injury and treatment failure. For this reason, techniques that aid in supporting safe advancement of a distal access catheter across a tortuous carotid siphon are essential.3,4 In this video, we demonstrate 2 ways in which this may be accomplished. The first technique uses a larger diameter microcatheter, such as the AXS Offset catheter (Stryker, Kalamazoo, Michigan), to increase support for the distal access catheter, while the second uses a buddy wire technique to accomplish this increased support. Both of these techniques can help increase the safety of navigating a tortuous carotid siphon and increase the likelihood of successful treatment. The procedures shown were performed with the informed consent of the patients.

Introduction PulseRider is a neck bridging device designed to aid in coiling of wide-neck intracranial aneurysms. When in place, it provides a ‘floor’ to the coil mass while allowing for easy access to the aneurysm sac, making it potentially suited for retreatment cases with limited working space. Methods Procedural success and outcomes of retreatment cases included in the AWARD (Safety Study of the PulseRider in Patients Undergoing Treatment for Bifurcation Intracranial Aneurysms) and ANSWER (Adjunctive Neurovascular Support for Wide-neck aneurysm Embolization and Reconstruction) studies are presented. Results Eleven PulseRider cases (10 female, mean age 50.9 years), 6 in AWARD and 5 in ANSWER, were retreatments of previously coiled aneurysms. Eight of the patients had 1 previous procedure, 2 had 2 previous treatments, and 1 had 3, including a failed attempt at Y-stenting. Mean aneurysm neck size was 4.98 mm (range 3.0–11.6 mm). Locations included basilar (7), carotid terminus (2) and MCA (2). PulseRider was successfully implanted with the ability to retain coils within the aneurysm in all cases. Immediately post-procedure, core lab adjudicated adequate occlusion rate was 91% (4/11 [36%] RR-I, 6/11 [55%] RR-II and 1/11 [9%] RR-III). At the one year follow up, the adjudicated rate of adequate aneurysm occlusion was 80% (6/10 [60%] RR-I, 2/10 [20%] RR-II, and 2/10 [20%] RR-III). There were no neurological deaths or major ipsilateral stroke (primary safety endpoint in the ANSWER study) and neurological decline was noted in one patient (the case of 3 previous treatments). Conclusion Retreatment of previously coiled wide-neck aneurysms with the PulseRider device resulted in 100% procedural success and 80% complete or near complete occlusion at 1 year with an acceptable safety profile. Disclosures A. Spiotta: 1; C; Microvention. 2; C; Penumbra, Minnetronix, Cerenovus. 6; C; Cerenovus, Penumbra, Microvention. D. Lopes: None. J. Mocco: 2; C; Rebound Medical, LLC, Cerebrotech Medical Systems, Inc., Snchroyn, Inc., EndoStream Medical, Ltd.. 4; C; Apama Medical, Inc., NeuroTechnology Investors, LLC., NeurVana Medical, LLC, Cerebrotech Medical Systems, Inc., Synchron, Inc., EndoStream Medical, Ltd., Stroke Project, Inc. A. Siddiqui: 2; C; Amnis Therapeutics, Boston Scientific, Canon Medical Systems USA, Cerebrotech Medical Systems, Claret Medical, Corindus, Endostream Medical, Guidepoint Global Consulting, Imperative Care, Integra, Rapid Medical, Rebound Therapeutics Corp., Silk Road Medical, StimMed, Stryker, Three Rivers Medical, VasSol, W.L. Gore & Associates, Cerenovus, Medtronic, MicroVention, Penumbra, Medical University of South Carolina, National PI/Steering Committee for POSITIVE Trial, Northwest University, DSMB Chair for HEAT Trial. 4; C; Amnis Therapeutics, Apama Medical, BlinkTBI, Buffalo Technology Partners, Cardinal Health, Cerebrotech Medical Systems, Claret Medical, Cognition Medical, Endostream Medical, Ltd, Imperative Care, International Medical Distribution Partners, Rebound Therapeutics Corp, Silk Road Medical, StimMed, Synchron, Three Rivers Medical, Viseon. S. Tateshima: 2; C; Cerenovus, Medtronic, Neurovasc, Stryker. 4; C; Neurovasc. H. Nahser: None.

Since the International Subarachnoid Aneurysm Trial,1 endovascular treatment has been the favored treatment for appropriate ruptured intracranial aneurysms. While our endovascular technology has advanced to allow us to treat the majority of intracranial aneurysms, simple coil embolization is still the most common modality. This video demonstrates the fundamentals of aneurysm catheterization and coiling for safe treatment. In addition, the set-up and devices are detailed. This video is to add to the library of basic techniques that will aid a large number of practitioners. This patient consented to endovascular treatment. The video demonstrates endovascular coil embolization of a posterior communicating artery aneurysm in a 76-yr-old female who presented with a subarachnoid hemorrhage. Image of biplane suite in video used courtesy of Siemens Medical Solutions USA, Inc. Illustration at 5:12 reprinted from Yasargil MG, et al, Microneurosurgery IV B, p. 9, Thieme, New York, 1995.

Background The new generation of flow diverters includes a surface modification with a synthetic biocompatible polymer, which makes the device more biocompatible and less thrombogenic. Optical coherence tomography (OCT) can be used to visualize perforators, stent wall apposition, and intra-stent thrombus. Unfortunately real world application of this technology has been limited because of the limited navigability of these devices in the intracranial vessels. In this report, we share our experience of using 3D-printed neurovascular anatomy models to simulate and test the navigability of a commercially available OCT system and to show the application of this device in a patient treated with the new generation of surface modified flow diverters. Material and methods Navigability of OCT catheters was tested in vitro using four different 3D-printed silicone replicas of the intracranial anterior circulation, after the implantation of surface modified devices. Intermediate catheters were used in different tortuous anatomies and positions. After this assessment, we describe the OCT image analysis of a Pipeline Shield for treating an unruptured posterior communicating artery (PCOM) aneurysm. Results Use of intermediate catheters in the 3D-printed replicas was associated with better navigation of the OCT catheters in favorable anatomies but did not help as much in unfavorable anatomies. OCT image analysis of a PCOM aneurysm treated with Pipeline Embolization Device Shield demonstrated areas of unsatisfactory apposition with no thrombus formation. Conclusions OCT improves the understanding of the flow diversion technology. The development of less thrombogenic devices, like the Pipeline Flex with Shield Technology, reinforces the need for intraluminal imaging for neurovascular application.

Transvenous embolization is an effective method for treating dural arteriovenous fistulas (DAVFs) of the transverse-sigmoid sinus (TSS). However, in cases of complicated DAVFs, it is difficult to preserve the patency of the dural sinus. The authors describe the technical details of a new reconstructive technique using transvenous balloon-assisted Onyx embolization as another treatment option in a patient with an extensive and complex DAVF of the left TSS.A microcatheter and compliant balloon catheter were navigated into the left internal jugular vein and placed at the distal end of the DAVF in the transverse sinus. The microcatheter was placed between the vessel wall of the TSS and the balloon. After the balloon was fully inflated, Onyx-18 was injected at the periphery of the balloon in a slow, controlled, progressive, stepwise manner; the balloon and microcatheter were simultaneously withdrawn toward the sigmoid sinus, with Onyx encompassing the entirety of the complex DAVF. The Onyx refluxed into multiple arterial feeders in a distal-to-proximal step-by-step manner, ultimately resulting in an Onyx tunnel. The final angiography study revealed complete obliteration of the DAVF and patency of the TSS.The Onyx tunnel, or reconstructive transvenous balloon-assisted Onyx embolization technique, may be an effective treatment option for large, complex DAVFs of the TSS. This technique may provide another option to facilitate the complete obliteration of the DAVF while preserving the functional sinus.

IntroductionThe LVIS stent system (LVIS and LVIS Junior) is a self-expanding, retrievable, microstent system indicated for the treatment of wide-necked cerebral aneurysms (WNAs). The present pivotal study was performed to evaluate the safety and effectiveness of this device.MethodsThe US LVIS pivotal trial was a prospective, multicenter, single-arm, interventional study conducted at 21 US centers. The study enrolled 153 adults with WNAs of the anterior and posterior circulations. The study was conducted under good clinical practices and included independent adjudication of all adverse events. The primary effectiveness endpoint was defined as successful aneurysm treatment with the LVIS System as evidenced by complete (100%) aneurysm occlusion at 12 months on conventional angiography without retreatment and without significant (≥50%) stenosis of the treated artery at 12 months as determined by an independent core laboratory. The primary safety endpoint was defined as the rate of stroke or death within 30 days, or ipsilateral stroke or neurologic death with 12 months.ResultsOne hundred and fifty-three patients enrolled at 21 investigational sites underwent attempted LVIS-assisted coil embolization. The mean age was 58.3±10.5 years and the majority of the participants (110/153, 71.9%) were female. Fifty-seven aneurysms (57/153, 37.3%) arose from the anterior cerebral artery, 43 (43/153, 28.1%) from the internal carotid artery, 17 (17/153, 11.1%) from the middle cerebral artery, 27 (27/153, 17.6%) from the basilar artery, six (6/153,3.9 %) from the PCA, and two from the vertebral artery. A single aneurysm arose from the superior cerebellar artery. The mean aneurysm dome height was 6.0±2.2 mm and mean width 5.5±2.3 mm. Mean neck width was 4.2±1.4 mm. A total of 22 participants presented for re-treatment of a previously ruptured (>30 days prior to treatment) target aneurysm. The primary effectiveness endpoint was observed in 70.6% (108/153) in the intent to treat population (ITT). Of the evaluable participants with follow-up 12-month angiography, 79.1 % (110/139) demonstrated complete occlusion– 92.1% (128/139) in this population demonstrated ≥95% occlusion and 95% demonstrated ≥90% occlusion (132/139). Eight participants (5.2%, 8/153) had at least one primary safety event in the ITT population.ConclusionThe LVIS stent system allows safe and highly effective coil embolization of WNAs.Clinical registration numberNCT01793792.

Background The Pipeline Flex (PED Flex; Medtronic, Dublin, Ireland) was designed to facilitate deployment and navigation compared to its previous iteration to reduce the rate of technical events and complications. Objective To assess the neurological morbidity and mortality rates of the PED Flex at 30 d. Methods Information from 9 neurovascular centers was retrospectively obtained between July 2014 and March 2016. Data included patient/aneurysm characteristics, periprocedural events, clinical, and angiographic outcomes. Multivariate logistic regression was performed to determine predictors of unfavorable clinical outcome (modified Rankin Scale [mRS] > 2). Results A total of 205 patients harboring 223 aneurysms were analyzed. The 30-d neurological morbidity and mortality rates were 1.9% (4/205) and 0.5% (1/205), respectively. The rate of intraprocedural events without neurological morbidity was 6.8% (14/205), consisting of intraprocedural ischemic events in 9 patients (4.5%) and hemorrhage in 5 (2.4%). Other technical events included difficulty capturing the delivery wire in 1 case (0.5%) and device migration after deployment in another case (0.5%). Favorable clinical outcome (mRS 0-2) was achieved in 186 patients (94.4%) at discharge and in 140 patients (94.5%) at 30 d. We did not find predictors of clinical outcomes on multivariate analysis. Conclusion The 30-d rates of neurological morbidity and mortality in this multicenter cohort using the PED Flex for the treatment of intracranial aneurysms were low, 1.9% (4/205) and 0.5% (1/205), respectively. In addition, technical events related to device deployment were also low, most likely due to the latest modifications in the delivery system.

A 64-year-old female presented with an incidentally-discovered right posterior inferior cerebral artery (PICA) aneurysm, initially treated in 2015 by simple coiling. Follow-up demonstrated significant coil compaction that required retreatment. Retreatment was done uneventfully using a Pipeline embolization device (PED) shield deployed starting from the basilar artery and ending at the V4 segment of the vertebral artery. Eight-weeks post-deployment, a follow-up digital subtraction imaging (DSA) and intravascular imaging with optical coherence tomography were obtained. The intravascular imaging demonstrated that the flow diverter had good wall apposition and concentric neointimal growth over the braid with exception to the areas that the PED was not in contact with the endothelial wall, such as at the right PICA ostium and at the vertebrobasilar junction. The entire procedure was safe, and the patient had no complications. In this article, we describe for the first time the assessment of the status of endothelial "healing" of the PED shield at 8-weeks.

BACKGROUND The effect of endovascular thrombectomy that is performed more than 6 hours after the onset of ischemic stroke is uncertain. Patients with a clinical deficit that is disproportionately severe relative to the infarct volume may benefit from late thrombectomy. METHODS We enrolled patients with occlusion of the intracranial internal carotid artery or proximal middle cerebral artery who had last been known to be well 6 to 24 hours earlier and who had a mismatch between the severity of the clinical deficit and the infarct volume, with mismatch criteria defined according to age (= 80 years). Patients were randomly assigned to thrombectomy plus standard care (the thrombectomy group) or to standard care alone (the control group). The coprimary end points were the mean score for disability on the utility-weighted modified Rankin scale (which ranges from 0 [death] to 10 [no symptoms or disability]) and the rate of functional independence (a score of 0, 1, or 2 on the modified Rankin scale, which ranges from 0 to 6, with higher scores indicating more severe disability) at 90 days. RESULTS A total of 206 patients were enrolled; 107 were assigned to the thrombectomy group and 99 to the control group. At 31 months, enrollment in the trial was stopped because of the results of a prespecified interim analysis. The mean score on the utility-weighted modified Rankin scale at 90 days was 5.5 in the thrombectomy group as compared with 3.4 in the control group (adjusted difference [Bayesian analysis], 2.0 points; 95% credible interval, 1.1 to 3.0; posterior probability of superiority, >0.999), and the rate of functional independence at 90 days was 49% in the thrombectomy group as compared with 13% in the control group (adjusted difference, 33 percentage points; 95% credible interval, 24 to 44; posterior probability of superiority, >0.999). The rate of symptomatic intracranial hemorrhage did not differ significantly between the two groups (6% in the thrombectomy group and 3% in the control group, P = 0.50), nor did 90-day mortality (19% and 18%, respectively; P = 1.00). CONCLUSIONS Among patients with acute stroke who had last been known to be well 6 to 24 hours earlier and who had a mismatch between clinical deficit and infarct, outcomes for disability at 90 days were better with thrombectomy plus standard care than with standard care alone. (Funded by Stryker Neurovascular; DAWN ClinicalTrials.gov number, NCT02142283.)