The Bicêtre occlusion scale is well suited to assess the efficacy of the Contour embolization device.

BACKGROUND: The Contour Embolization Device (CED) is typically assessed using coiling angiographic outcomes. However, these scales do not address device-specific problematics. We evaluated the usability of the Bicêtre occlusion scale (BOS) with the CED. RESULTS: BOS scores can be analyzed as BOSS 0 = no residual flow, BOSS 1 = residual flow inside the CED but with complete neck-sealing, BOSS 2 = neck-remnant, BOSS 3 = aneurysm-remnant, BOSS 1 + 3 = contrast filling inside the device and aneurysmal sac without complete neck-sealing. CONCLUSION: BOS usage should be encouraged as it provides a more comprehensive assessment of the mechanism of CED occlusion, especially considering the potential prognostic value of the neck sealing assessment.

Endovascular approach to posterior spinal cord AV shunts via the anterior spinal artery.

Intradural spinal cord arteriovenous shunts are challenging vascular lesions with poor prognosis if left untreated. Therapeutic options include endovascular treatment, microsurgery or a combined approach. Surgical approaches are more complex if the lesions are located anteriorly and supplied by the anterior spinal artery (ASA). ASA can also vascularize shunts located on the posterior surface of the spinal cord either by transmedullary arteries, pial circumferential arteries or, if affecting the lower portions of the cord, by the anastomotic channels of the basket. Each of these vessels can be used for endovascular navigation to reach the shunts with good results if appropriate anatomical rules are followed. We describe here some technical considerations based on the anatomical analysis for the embolization of posterior spinal cord arteriovenous shunts vascularized by the anterior spinal artery.

How a decade of aneurysms embolization with the Woven EndoBridge has changed our understanding and practices?

BACKGROUND: Safety and efficacy of the WEB (Woven EndoBridge) device have been extensively evaluated in several good clinical practice studies. Nonetheless, the WEB had several structural evolutions overtime up to the fifth generation WEB device (WEB17). Here, we tried to understand how this may have modified our practices and enlarged our indications for its use. METHODS: We retrospectively analyzed data from all patients with aneurysms treated (or intended to be treated) with a WEB at our institution between July 2012 and February 2022. The time frame was split in two periods: before and after the arrival of the WEB17 in our center (February 2017). RESULTS: 252 patients with 276 wide-necked aneurysms were included; 78 aneurysms (28.2%) were ruptured. Successful embolization with a WEB device was achieved in 263/276 aneurysms (95.3%). With the availability of WEB17, treated aneurysms were significantly smaller (8.2 mm versus 5.9 mm, p<0.001) and off-label location significantly increased (4.4% versus 17.3%, p = 0.02) with an increase of sidewall aneurysm (4.4% versus 11.6%, p = 0.06). Also, WEB were more significantly oversized (1.05 versus 1.11, p<0.01). Adequate and complete occlusion rates increased constantly during the two periods (54.8% versus 67.5%, p = 0.08 and 74.2% versus 83.7%, p = 0.10, respectively). The proportion of ruptured aneurysms slightly increased between the two periods (24.6% versus 29.5%, p = 0.44). CONCLUSIONS: Over the first decade of its availability, the WEB device usage shifted towards smaller aneurysms and broader indications, including ruptured aneurysms. The oversizing strategy also became the standard of practice for WEB deployment in our institution.

Comparison of arterial wall integration of different flow diverters in rabbits: The CICAFLOW study.

BACKGROUND AND PURPOSE: New coated flow diverters (FDs) claim antithrombotic properties and increased arterial wall integration. The aim of this study is to compare in vivo endothelial coverage of coated and uncoated FD in the context of different antiplatelet regimens. METHODS: Different FDs (Silk Vista - SV, Pipeline with Shield technology - PED shield and Surpass Evolve - SE) were implanted in the aorta of rabbits, all 3 in each animal with 3 different antiplatelet regimens: no antiplatelet therapy, aspirin alone, or aspirin and ticagrelor. Four weeks after FD implantation, angiography, flat-panel CT, and optical coherence tomography (OCT) were performed before harvesting the aorta. Extensive histopathology analyses were performed including environmental scanning electron microscopy (ESEM), multiphoton microscopy (MPM) and histological staining with qualitative and/or quantitative assessment of device coverage. RESULTS: All 23 FDs that were implanted remained patent without hyperplasia. Qualitative stent coverage assessment revealed that there were no statistically significant differences between the FD groups (p = 0.19, p = 0.45, p = 0.40, and p = 0.84 for OCT, ESEM, MPM and histology, respectively). Quantitative neointimal measurement of histological sections also showed similar results in all 3 FD groups (p = 0.70). However, there were significant differences between the 3 groups of antiplatelet regimens (p = 0.07) with a higher rate in the no antiplatelet group (p = 0.05 versus aspirin alone and p = 0.03 versus aspirin and ticagrelor). CONCLUSION: Our study provides evidence that FD integration into the arterial wall is similar with coated (PED shield) and uncoated devices (SV, SE), regardless of the antiplatelet regimen. FD integration with specific surface coverage should be promoted. TRIAL REGISTRATION: APAFIS #2022011215518538.

Safety and effectiveness of the LVIS and LVIS Jr devices for the treatment of intracranial aneurysms: Final results of the LEPI multicenter cohort study.

BACKGROUND: The Low profile visualized intraluminal support (LVIS)/LVIS Jr is a self-expanding braiding stent for the treatment of intracranial aneurysm. This study is to determine the safety and effectiveness of the LVIS/LVIS Jr for the treatment of intracranial aneurysms in a real-world setting. METHODS: This prospective, observational, multicenter study enrolled patients with unruptured, ruptured and recanalized intracranial aneurysms treated with the LVIS stents, between February 2018 to December 2019. Primary endpoint was the cumulative morbidity and mortality rate (CMMR) assessed at 12 months follow-up (FU). RESULTS: A total of 130 patients were included (62.3 % women, mean age 55.9 ± 11.4) on an intention-to-treat basis. Four patients (3.1 %) had 2 target aneurysms; 134 total aneurysms were treated. The aneurysms were mainly located on the middle cerebral artery (41/134; 30.6 %) and the anterior communicating artery (31/134; 23.1 %). The CMMR at 1 year linked to the procedure and/or device was 4.6 % (6/130). The overall mortality was 1.5 % (2/130), none of these deaths adjudged as being linked to the procedure and/or device. All aneurysms (134/134, 100 %) were successfully treated with LVIS stent and/or other devices. At a mean FU of 16.8 months post-procedure, complete/nearly complete occlusion was achieved in 112 aneurysms (92.6 %), and only 3 patients (2.5 %) required aneurysm retreatment. CONCLUSION: This study provides evidence that the LVIS/LVIS Jr devices are safe and effective in the treatment of complex intracranial aneurysms, with very high rates of adequate occlusion at FU. These angiographic results are stable over time with an acceptable complication rate. TRIAL REGISTRATION: ClinicalTrial.gov under NCT03553771.

Association between flow patterns of the posterior cerebral arterial circle and basilar-tip aneurysms.

PURPOSE: The Cerebral arterial circle presents multiple individual anatomical configurations which are of the highest importance regarding the pathological processes for intracranial aneurysms development. Previous studies highlighted the importance of geometry and especially arterial bifurcations leading to aneurysms development. The primary objective of this study was to determine whether a flow pattern asymmetry of the P1 segments of the posterior cerebral arteries was associated with a higher risk of basilar tip aneurysm. MATERIAL AND METHODS: Two different populations were retrospectively reviewed. The first population, without aneurysm, for which TOF MRI sequences were reviewed. The second population with patients harboring basilar tip aneurysms for whom cerebral angiograms were reviewed. We retrospectively analyzed the flow contribution and symmetry of the two right and left P1 segments of the posterior cerebral arteries and the two posterior communicating arteries (Pcomm). We analyzed the association and risk factors for basilar tip aneurysm. RESULTS: The anatomical and flow configurations of P1 and Pcomm have been reviewed in 467 patients without aneurysms and 35 patients with aneurysms. We identified a significant association between the flow pattern asymmetry of the P1 segments and the presence of a basilar tip aneurysm (OR = 2.12; IC95% = [1.01-4.36]; p = 0.04). We also confirmed that the male gender was protective against aneurysm (OR = 0.45; IC95% = [0.194-0.961]; p = 0.04). CONCLUSION: Non-modal basilar tip bifurcation and flow asymmetry of P1 segments are associated with an increased risk of basilar tip aneurysm. These findings highlight the importance of analyzing MRI-TOF of the posterior configuration of the Cerebral arterial circle to potentially refine the aneurysms risk prediction.

Benefit of mechanical thrombectomy in acute ischemic stroke related to calcified cerebral embolus.

PURPOSE: Mechanical thrombectomies (MT) in patients with large vessel occlusion (LVO) related to calcified cerebral embolus (CCE) have been reported, through small case series, being associated with low reperfusion rate and worse outcome, compared to regular MT. The purpose of the MASC (Mechanical Thrombectomy in Acute Ischemic Stroke Related to Calcified Cerebral Embolus) study was to evaluate the incidence of CCEs treated by MT and the effectiveness of MT in this indication. METHODS: The MASC study is a retrospective multicentric (n = 37) national study gathering the cases of adult patients who underwent MT for acute ischemic stroke with LVO related to a CCE in France from January 2015 to November 2019. Reperfusion rate (mTICI ≥ 2B), complication rate and 90-day mRS were systematically collected. We then conducted a systematic review by searching for articles in PubMed, Cochrane Library, Embase and Google Scholar from January 2015 to March 2020. A meta-analysis was performed to estimate clinical outcome at 90 days, reperfusion rate and complications. RESULTS: We gathered data from 35 patients. Reperfusion was obtained in 57% of the cases. Good clinical outcome was observed in 28% of the patients. The meta-analysis retrieved 136 patients. Reperfusion and good clinical outcome were obtained in 50% and 29% of the cases, respectively. CONCLUSION: The MASC study found worse angiographic and clinical outcomes compared to regular thrombectomies. Individual patient-based meta-analysis including the MASC findings shows a 50% reperfusion rate and a 29% of good clinical outcome.

CD31 Mimetic Coating Enhances Flow Diverting Stent Integration into the Arterial Wall Promoting Aneurysm Healing.

BACKGROUND AND PURPOSE: Beyond aneurysmal occlusion, metallic flow diverters (FDs) can induce an adverse endovascular reaction due to the foreignness of metal devices, hampering FD endothelialization across the aneurysm neck, and arterial healing of intracranial aneurysms. Here, we evaluated the potential benefits of an FD coating mimicking CD31, a coreceptor critically involved in endothelial function and endovascular homeostasis, on the endothelialization of FDs implanted in vivo. METHODS: Nitinol FD (Silk Vista Baby) and flat disks were dip-coated with a CD31-mimetic peptide via an intermediate layer of polydopamine. Disks were used to assess the reaction of endothelial cells and blood elements in vitro. An aneurysm rabbit model was used to compare in vivo effects on the arterial wall of CD31-mimetic-coated (CD31-mimetic, n=6), polydopamine-coated (polydopamine, n=6), and uncoated FDs (bare, n=5) at 4 weeks post-FD implantation. In addition, long-term safety was assessed at 12 weeks. RESULTS: In vitro, CD31-mimetic coated disks displayed reduced adhesion of blood elements while favoring endothelial cell attachment and confluence, compared to bare and polydopamine disks. Strikingly, in vivo, the neoarterial wall formed over the CD31-mimetic-FD struts at the aneurysm neck was characteristic of an arterial tunica media, with continuous differentiated endothelium covering a significantly thicker layer of collagen and smooth muscle cells as compared to the controls. The rates of angiographic complete occlusion and covered branch arterial patency were similar in all 3 groups. CONCLUSIONS: CD31-mimetic coating favors the colonization of metallic endovascular devices with endothelial cells displaying a physiological phenotype while preventing the adhesion of platelets and leukocytes. These biological properties lead to a rapid and improved endothelialization of the neoarterial wall at the aneurysm neck. CD31-mimetic coating could therefore represent a valuable strategy for FD biocompatibility improvement and aneurysm healing.

Intensive therapies of delayed cerebral ischemia after subarachnoid hemorrhage: a propensity-matched comparison of different center-driven strategies.

BACKGROUND: Intensive therapies of delayed cerebral ischemia (DCI) following aneurysmal subarachnoid hemorrhage (aSAH) have still controversial and unproven benefit. We aimed to compare the overall efficacy of two different center-driven strategies for the treatment of DCI respectively with and without vasospasm angioplasty. METHODS: Two hundred consecutive patients with aSAH were enrolled in each of two northern European centers. In an interventional center, vasospasm angioplasty was indicated as first line rather than rescue treatment of DCI using distal percutaneous balloon angioplasty technique combined with intravenous milrinone. In non-interventional center, induced hypertension was the only intensive therapy of DCI. Radiological DCI (new cerebral infarcts not visible on immediate post-treatment imaging), death at 1 month, and favorable outcome at 6 months (modified Rankin scale score ≤ 2) were retrospectively analyzed by independent observers and compared between two centers before and after propensity score (PS) matching for baseline characteristics. RESULTS: Baseline characteristics only differed between centers for age and rate of smokers and patients with chronic high blood pressure. In the interventional center, vasospasm angioplasty was performed in 38% of patients with median time from bleeding of 8 days (Q1 = 6.5;Q3 = 10). There was no significant difference of incidence of radiological DCI (9% vs.14%, P = 0.11), death (8% vs. 9%, P = 0.4), and favorable outcome 74% vs. 72% (P = 0.4) between interventional and non-interventional centers before and after PS matching. CONCLUSIONS: Our results suggest either that there is no benefit, or might be minimal, of one between two different center-driven strategies for intensive treatment of DCI. Despite potential lack of power or unknown confounders in our study, these results question the use of such intensive therapies in daily practice without further optimization and validation.

Multiphoton microscopy for pre-clinical evaluation of flow-diverter stents for treating aneurysms.

BACKGROUND: Conventional histological analyses are the gold standard for the study of aneurysms and vascular pathologies in pre-clinical research. Over the past decade, in vivo and ex vivo imaging using multiphoton microscopy have emerged as powerful pre-clinical tools for detailed tissue analyses that can assess morphology, the extracellular matrix (ECM), cell density and vascularisation. Multiphoton microscopy allows for deeper tissue penetration with minor phototoxicity. OBJECTIVE: The present study aimed to demonstrate the current status of multimodality imaging, including multiphoton microscopy, for detailed analyses of neo-endothelialisation and ECM evolution after flow-diverter stent (FDS) treatment in an experimental rabbit model of aneurysms. METHODS: Multiphoton microscopy tools for assessing autofluorescence and second harmonic generation (SHG) signals from biological tissues were used to evaluate the endovascular treatment of intracranial aneurysms in an animal model of aneurysms (pig, rabbit). Results from multiphoton microscopy were compared to those from standard histology, electronic and bright field microscopy. CONCLUSIONS: The present study describes novel evaluation modes based on multiphoton microscopy for visualising tissue morphology (e.g., collagen, elastin, and cells) to qualify and quantify the extent of neo-intimal formation of covered arteries and device integration into the arterial wall using a rabbit model of intracranial aneurysms treated with FDS.

Mechanical Thrombectomy for Acute Ischemic Stroke Amid the COVID-19 Outbreak: Decreased Activity, and Increased Care Delays.

BACKGROUND AND PURPOSE: The efficiency of prehospital care chain response and the adequacy of hospital resources are challenged amid the coronavirus disease 2019 (COVID-19) outbreak, with suspected consequences for patients with ischemic stroke eligible for mechanical thrombectomy (MT). METHODS: We conducted a prospective national-level data collection of patients treated with MT, ranging 45 days across epidemic containment measures instatement, and of patients treated during the same calendar period in 2019. The primary end point was the variation of patients receiving MT during the epidemic period. Secondary end points included care delays between onset, imaging, and groin puncture. To analyze the primary end point, we used a Poisson regression model. We then analyzed the correlation between the number of MTs and the number of COVID-19 cases hospitalizations, using the Pearson correlation coefficient (compared with the null value). RESULTS: A total of 1513 patients were included at 32 centers, in all French administrative regions. There was a 21% significant decrease (0.79; [95%CI, 0.76-0.82]; P<0.001) in MT case volumes during the epidemic period, and a significant increase in delays between imaging and groin puncture, overall (mean 144.9±SD 86.8 minutes versus 126.2±70.9; P<0.001 in 2019) and in transferred patients (mean 182.6±SD 82.0 minutes versus 153.25±67; P<0.001). After the instatement of strict epidemic mitigation measures, there was a significant negative correlation between the number of hospitalizations for COVID and the number of MT cases (R2 -0.51; P=0.04). Patients treated during the COVID outbreak were less likely to receive intravenous thrombolysis and to have unwitnessed strokes (both P<0.05). CONCLUSIONS: Our study showed a significant decrease in patients treated with MTs during the first stages of the COVID epidemic in France and alarming indicators of lengthened care delays. These findings prompt immediate consideration of local and regional stroke networks preparedness in the varying contexts of COVID-19 pandemic evolution.

Secondary S100B Protein Increase Following Brain Arteriovenous Malformation Rupture is Associated with Cerebral Infarction.

Early S100B protein serum elevation is associated with poor prognosis in patients with ruptured brain arteriovenous malformations (BAVM). The purpose of this study is to determine whether a secondary elevation of S100B is associated with early complications or poor outcome in this population. This is a retrospective study of patients admitted for BAVM rupture. A secondary increase of S100B was defined as an absolute increase by 0.1 µg/L within 30 days of admission. Fisher's and unpaired t tests followed by multivariate analysis were performed to identify markers associated with this increase. Two hundred and twenty-one ruptures met inclusion criteria. Secondary S100B protein serum elevation was found in 17.1% of ruptures and was associated with secondary infarction (p < 0.001), vasospasm-related infarction (p < 0.001), intensive care (p = 0.009), and hospital length of stay (p = 0.005), but not with early rebleeding (p = 0.07) or in-hospital mortality (p = 0.99). Secondary infarction was the only independent predictor of secondary increase of S100B (OR 9.9; 95% CI (3-35); p < 0.001). Secondary elevation of S100B protein serum levels is associated with secondary infarction in ruptured brain arteriovenous malformations.

Thrombectomy or intravenous thrombolysis in patients with NIHSS of 5 or less?

BACKGROUND AND PURPOSE: To compare outcomes of minor stroke patients with intracranial vessel occlusions (IVO) underwent mechanical thrombectomy (MT) versus those treated with intravenous thrombolysis alone (IVT). METHODS: We retrospectively reviewed two large prospective stroke databases from two European centers searching for patients admitted with minor stroke (i.e. NIHSS Score░≤░5), baseline mRS░=░0 and occlusion of the M1-M2 segment of the middle cerebral artery (MCA). Groups receiving (A) IVT alone and (B) MT+/-IVT were compared. Primary outcome measures were MT safety, successful recanalization rate (mTICI 2b-3) and NIHSS shift (discharge NIHSS minus admission NIHSS); secondary outcomes included discharge rates and excellent outcome (mRS 0-1) at 3 months. Univariate and multivariate analyses were performed. RESULTS: Thirty-two patients were enrolled in Group B (19░MT alone; 13 MT░+░IVT) and 24 in Group A. Successful recanalization (mTICI 2b-3) was obtained in 100% of cases in Group B vs 38% in Group A. Symptomatic hemorrhagic transformation rate did not differ between the two groups. Multivariate analysis reported MT as the only predictor of early (<░12░h) favorable NIHSS shift and lower NIHSS at discharge. Moreover, discharge at home and excellent outcome at 3-month follow-up were statistically associated with MT. CONCLUSIONS: MT in patients with minor strokes and intracranial vessel occlusion (IVO) is safe and can determine a rapid improvement of NIHSS Score. MT seems also associated with a higher rate of patients discharged at home after hospitalization and better clinical outcome at 3-month follow-up. Larger randomized trials are warranted to confirm these results.

Hamate and pisiform coalition: a case report and introduction to the carpal C-sign on lateral radiograph.

Hamate-pisiform coalition is an exceptional form of carpal coalition. Case reports are essential to gain a better understanding of this variant. We report a case of congenital bilateral hamate-pisiform coalition in a 20-year-old male discovered in the context of a right wrist trauma. Radiographs also revealed a bilateral scapholunate diastasis. Clinical examination and radiological findings suggested that the right wrist scapholunate diastasis was related to scapholunate instability. Left wrist scapholunate diastasis could be related to (1) a pathological feature or (2) a normal variant associated with hamate-pisiform coalition. Lateral radiographs showed a volar C-shaped osseous bridge corresponding to the coalition. We associated it with a new sign: the "carpal C-sign". Computed tomography with three-dimensional reconstruction provides helpful information about the type of coalition (osseous versus non-osseous) and excludes potential fracture. We discuss the specific embryologic features of the hamate-pisiform coalition, as well as its prevalence, radiographic classification, clinical significance, and treatment.

Thromboembolic Events With the Woven Endobridge Device: Incidence, Predictive Factors, and Management.

BACKGROUND AND OBJECTIVES: The Woven EndoBridge (WEB) device has been increasingly used to treat wide-neck aneurysms showing a safe and effective profile, but a relatively high number of thromboembolic events (TEEs) have been reported with such treatment. We aimed to evaluate the incidence and management of TEEs and possible predictive factors related to WEB embolization of ruptured and unruptured intracranial aneurysms. METHODS: A single-center database with consecutive aneurysms treated with a WEB device between July 2012 and May 2022 was reviewed for intraoperative and delayed TEEs. Univariate and multivariable analyses were used to determine factors associated with TEEs. RESULTS: A total of 266 independent aneurysms were treated with WEB devices in 245 patients (mean age 55.78 ± 11.64 years, 169 (63.5%) females, 80 (30%) ruptured). The overall rate of TEEs is 13% (35/266), including 8.7% intraoperative. Symptomatic TEEs with clinical sequelae at a 3-month follow-up are reported to be 2.6% (7/266) with no TEE-related mortality. Both the replacement of a WEB device during the procedure (adjusted odds ratio = 2.61, 95% CI 1.24-5.49; P = .01) and ruptured aneurysms (adjusted odds ratio = 2.74, 95% CI 1.31-5.7; P = .007) were independent predictors of TEEs. A case-by-case management of intraprocedural TEE is also presented; tirofiban was successfully used in most cases of this cohort. CONCLUSION: In this study, we demonstrated that ruptured aneurysms and WEB device replacement during the procedure were independent predictive factors for TEEs. As a result, making the correct choice of WEB is crucial for improving treatment outcomes. Moreover, with proper medical management of TEEs, minimal morbidity and no mortality could be achieved, which reinforces the safety of the technique.

Endovascular Thrombectomy for Carotid Pseudo-occlusion in the Setting of Acute Ischemic Stroke: A Comparative Systematic Review and Meta-Analysis.

BACKGROUND: The effective treatment for acute ischemic stroke (AIS) patients with cervical internal carotid pseudo-occlusion (cICA-PO) requires comprehensive research on the safety and outcomes of endovascular thrombectomy (EVT). However, there is limited data available, highlighting the need for further research to ensure better treatment strategies and improve the quality of care for these patients. PURPOSE: This study aims to assess the management and outcomes in this population group compared to patients with true carotid occlusion. DATA SOURCES: Following the PRISMA guidelines, a comprehensive systematic review was conducted using PubMed, Embase, Web of Science, and Scopus from data base inception to November 2023. STUDY SELECTION: The size of the included studies ranged from 16 patients to 146 patients. Through the 4 full-text articles, a total of 259 patients were collected. We compared outcomes between patients with cICA-PO compared to patients with true carotid occlusions undergoing EVT due to AIS. We excluded studies with patients with carotid pseudo-occlusion without stroke, review articles, duplicate studies, overlapped data that included the same patients presented in another included study, case reports, case series with fewer than 5 patients, and meeting abstracts that did not contain the outcomes of interest. We did not pose any limitations regarding sample size or patients' characteristics. DATA ANALYSIS: We utilized the R statistical software (V.4.3.1; R package meta, R Foundation for Statistical Computing, Vienna, Austria) to conduct the analysis of all the data obtained. We calculated the odds ratio (OR) for binary variables, and the corresponding 95% confidence interval (CI). To synthesize the data, random-effect models, as well as forest plots were generated to visually represent the synthesis of the data. Additionally, we assessed heterogeneity using Cochran's Q and I2 tests. A P-value less than 0.05 for the Q statistic or I2 more than 50% suggests significant heterogeneity. Based on a small number of studies (less than 10), the assessment of publication bias could not be reliably performed. DATA SYNTHESIS: This meta-analysis encompassed data from 4 studies. Patients with cICA-PO and AIS who underwent EVT (n = 135) exhibited lower rates of functional independence (OR 0.35, 95% CI 0.20-0.61, p= <0.001) compared to patients with true occlusions (n = 103), as well as successful recanalization rates (OR 0.39, 95% CI 0.20-0.74, p=0.004). In addition, the cICA-PO group experienced higher mortality and sICH compared to the group with true carotid occlusions (OR 2.62, 95% CI 0.21-7.24, and OR 2.23, 95% CI 1.00-4.95, p= 0.049, respectively). LIMITATIONS: Individual patient data was not available. Studies were a retrospective design and some of the studies had small sample sizes. The included studies in our metaanalysis did not exclude patients with tandem occlusions which might influence the results of the comparison. CONCLUSIONS: As compared to patients with true carotid occlusion, the cICA-PO group with AIS undergoing EVT presented poor outcomes with lower functional independence and successful recanalization, as well as higher sICH and mortality rates.

Creating elastase aneurysms in rabbits: a video primer.

The New Zealand rabbit elastase-induced arterial aneurysm of the right common carotid artery remains a widely used model for assessing the effectiveness and safety of new neuroendovascular devices.1 This model offers a simple and reliable platform for pre-clinical in vivo investigations, crucial for comprehending the biological processes underlying aneurysm healing after endovascular treatment.2 Notably, the induced aneurysm exhibits morphological, hemodynamic, and histological characteristics similar to human intracranial aneurysms. The creation of the aneurysm is performed using open and endovascular techniques. Each step of the procedure requires a meticulous and controlled gesture to ensure reproducibility of the aneurysm and minimize animal misuse. In video 1 we present a step-by-step procedural guide for aneurysm creation and follow-up. We hope this resource will help in promoting this model and provide useful guidance for researchers in the field.neurintsurg;jnis-2024-021912v1/V1F1V1Video 1Surgical procedure of creating elastase-induced aneurysms in rabbits.

Preclinical in vitro and in vivo results of the new silk vista flow diverter with P8RI coating.

BACKGROUND: Flow diverting stents (FDS) have transformed the treatment of intracranial aneurysms; however, their metallic structure associated with their intra-luminal positioning hamper angiographic and clinical outcomes. Therefore, there is a need to develop FDS with optimized surfaces that reduce thrombogenicity while promoting the healing process and endothelialization. METHODS: P8RI, a peptide mimicking the CD31 protein, was previously developed and grafted onto Silk Vista (SV) FDS. P8RI-SV and bare-SV were used in vitro in a blood loop model to test their hemocompatibility using human whole blood and in vivo using the rabbit elastase model for optical coherence tomography (OCT) comparisons of neointimal formation at day 5 and day 28. RESULTS: After blood loop incubation, P8RI-SV showed significant reduction in fibrin binding (p=0.004) and platelet adhesion (p=0.041) compared with bare-SV. Similarly, derivative markers measured in blood, thromboxane B2 (platelet activation) and Thrombin-Antithrombin III complexes (coagulation activation), were also significantly reduced in the P8RI-SV group (both p=0.002). In vivo, complete or near-complete occlusion was reached in all aneurysms (n=6) at day 28. Excellent rate of stent-coverage ratio was obtained at day 5 (89.3% (79.1%-98.7%)) comparable to the observation at day 28 (91.8% (79.1%-100%); p=0.44). These rates were significantly higher compared with bare-SV at day 5 (77.8% (58.3%-86.8%); p<0.001) and at day 28 (67.7% (52.6%-88.9%); p<0.0001). CONCLUSION: In vitro results confirm enhanced hemocompatibility with a significant anti-thrombotic effect of the P8RI-SV. In vivo results provide evidence of rapid neo-intimal growth reaching near-complete tissue healing as early as day 5 in a rabbit model.

Mechanical thrombectomy in basilar artery occlusions: impact of first-line strategy as a function of the occlusion level.

BACKGROUND: Retrospective studies suggest the superiority of first-line contact aspiration (CA) thrombectomy over stent-retriever (SR) in basilar artery occlusions (BAO). We aimed to investigate the impact of first-line mechanical thrombectomy per the occlusion level, considering differences in stroke etiology prevalence between proximal and distal BAO. METHODS: A retrospective, multicentric analysis of the Endovascular Treatment in Ischemic Stroke Registry (ETIS) included consecutive BAO patients treated from January 2016 to May 2022. Patients were categorized into SR (±aspiration) and CA alone groups. Occlusion levels were determined through digital subtraction angiography. Favorable clinical outcome was defined as 90-day modified Rankin Scale (mRS) 0-3. RESULTS: A total of 380 patients were analyzed (251 CA alone, 129 SR±aspiration). Globally, first-line SR showed lower recanalization rates (89.1% vs 94.8%, OR=0.29, 95% CI 0.16 to 0.53; p<0.001) and worse clinical outcomes (mRS 0-3: 46.0% vs 52.2%, OR=0.62, 95% CI 0.44 to 0.87; p=0.006) compared with CA. In proximal occlusions, SR was significantly associated with poorer clinical outcomes (mRS 0-3: 20.9% vs 37.1%; OR=0.40, 95% CI 0.19 to 0.83; p=0.014) despite similar recanalization rates. Conversely, in distal occlusions there was no difference in clinical outcomes although recanalization rates were higher with CA (modified Thrombolysis in Cerebral Infarction score (mTICI 2b/3): 97.7% vs 91.7%; OR=0.17, 95% CI 0.05 to 0.66; p=0.01). CONCLUSIONS: In our BAO population, CA demonstrated better angiographic outcomes in middle and distal occlusions and better clinical outcomes in proximal occlusions. This translated into better angiographic and clinical results in the global study population. Clinical results were particularly influenced by the negative impact of SR on 90-day mRS, independently of recanalization rates in proximal BAO.