Rejection Via Video The Impact of Observed Group and Individual Rejection

This study introduces an easy-to-implement, controlled, vivid, and functional rejection paradigm. Participants empathized with the protagonist of a video who was rejected or accepted individually or as part of a group. In the rejection condition, more perceived exclusion and lower basic need fulfillment were reported. The paradigm also induced nuance in situational factors: Observing somebody being rejected as part of a group led to less pronounced reactions than individual rejection. The video-based rejection paradigm taps into the less studied area of group rejection and offers a new method to test established and novel theoretical predictions

Influence of the initial chemical conditions on the rational design of silica particles

The influence of the water content in the initial composition on the size of silica particles produced using the Stöber process is well known. We have shown that there are three morphological regimes defined by compositional boundaries. At low water levels (below stoichiometric ratio of water:tetraethoxysilane), very high surface area and aggregated structures are formed; at high water content (>40 wt%) similar structures are also seen. Between these two boundary conditions, discrete particles are formed whose size are dictated by the water content. Within the compositional regime that enables the classical Stöber silica, the structural evolution shows a more rapid attainment of final particle size than the rate of formation of silica supporting the monomer addition hypothesis. The clearer understanding of the role of the initial composition on the output of this synthesis method will be of considerable use for the establishment of reliable reproducible silica production for future industrial adoption

Abstract 038: Fusiform/Dissecting vs. Saccular Posterior Circulation Aneurysms Treated with Flow Diversion: A Multicenter Study

Introduction Flow diverters have demonstrated reliable safety and effectiveness for the treatment of selected anterior circulation intracranial aneurysms. However, posterior circulation aneurysms comprise around 10‐15% of all aneurysms, and they frequently present atypical morphological and anatomical characteristics. Furthermore, these lesions have an increased risk of rupture (compared to those in the anterior circulation) with respect to size and higher treatment risks (regardless of the technique). Flow diversion in posterior circulation aneurysms has been described previously with inconsistent clinical and radiological results. Hence, we aimed to compare the safety and effectiveness of FDs in fusiform/dissecting vs. saccular aneurysms located in the vertebrobasilar vessels. Methods We performed a multicenter, retrospective cohort study including 9 centers. All patients treated with FDs for aneurysms located in the posterior circulation (vertebral and basilar arteries) between 2015 and 2022 were included. Patients were divided into two groups according to the morphology of the aneurysm (fusiform/dissecting vs. saccular). The effectiveness outcome was complete aneurysm occlusion (Raymond‐Roy Class 1) at the latest follow‐up. Safety outcomes included the incidence of ischemic/hemorrhagic and mortality. After adjusting for confounders multivariable logistic regressions were performed to compare outcomes of interest. Results A total of 147 patients with 147 aneurysms were included. The fusiform/dissecting group included 85 cases, while the saccular group 62. The saccular group had older patients (median age: fusiform/dissecting, 55 years [45‐64] vs. saccular, 63 years [51‐70.0]; p=.02). The number of female patients was not different between groups (fusiform/dissecting, 42% vs. saccular, 58%; p=.05). Clinical presentation, comorbidities, modified Fisher, and Hunt and Hess were similar. Baseline modified Rankin Score (mRS) was different (mRS 0‐2: fusiform/dissecting, 84% vs. saccular, 98%; p=.030). Previous endovascular treatment (p=.396) was similar. Aneurysm location (most were in the vertebral artery: fusiform/dissecting, 60% vs. saccular, 42%; p=.009) was different. Median aneurysm size (fusiform/dissecting, 10.0 mm [6.5‐18.8] vs. saccular, 5.9 [3.0‐10.0]; p=1 FD: fusiform/dissecting, 36% vs. saccular, 10%; p=<.001) and adjunctive coiling (fusiform/dissecting, 89% vs. non‐F, 74%; p= .015) were different. The most commonly implanted was Pipeline Flex (fusiform/dissecting, 55%, vs. saccular, 40%). Thromboembolic (fusiform/dissecting, 8.2%, vs. saccular, 8.1%; p=.97) and hemorrhagic (fusiform/dissecting, 4%, vs. saccular, 10%; p=.125). Mortality was increased in the fusiform/dissecting group (19%) vs saccular (12%) but not different (p=.365). At an overall median follow‐up time of 13.5 [7.4‐28.8] months, complete occlusion was lower in the fusiform/dissecting group (61% vs. F, 63%) but not statistically different (p=.356). Follow‐up mRS was not different (mRS 0‐2: fusiform/dissecting, 73% vs. saccular, 76%; p=.365). 172 (71%) of the cases achieved complete aneurysm occlusion. Multivariable analysis showed that age (OR: 0.96; 95%CI: 0.93‐0.99; p=.008) and location in the basilar artery (OR: 0.09; 95%CI: 0.03‐0.29; p=<.001) were associated with incomplete occlusion at follow‐up. Conclusion Our results suggest that flow diversion can be an effective treatment for fusiform/dissecting and saccular aneurysms located in the posterior circulation. Although the occlusion rates after flow diversion in fusiform/dissecting aneurysms showed a lower rate compared to saccular, the favorable safety profile of FDs allows them to be considered a valuable tool in the neuroinventionalist armamentarium

Abstract Number: LBA5 Predictors of Occlusion After Flow Diversion of Internal Carotid Artery Aneurysms: A Pooled Analysis

Introduction Flow diverters (FDs) have demonstrated a safe and effective profile for the treatment of intracranial aneurysms with complex morphologies and variable anatomic locations. However, aneurysmal persistence after flow diversion still presents in up to 25% of treated aneurysms. Herein, we aimed to perform a pooled analysis of two large studies (SCENT [Surpass Intracranial Aneurysm Embolization System Pivotal Trial to Treat Large or Giant Neck Wide Neck Aneurysms] and SESSIA [Safety and Efficacy of the Surpass Streamline for Intracranial Aneurysms]) to evaluate the predictors of occlusion at final follow‐up after treatment with a 72–96 wire device. Methods We pooled all data from the SCENT (prospective) and SESSIA (retrospective) studies that included patients treated with the Surpass Streamline. From the studies, a subset of patients with unruptured saccular aneurysms located in the internal carotid artery (ICA) up to its terminus were included. The authors collected baseline demographics, comorbidities, aneurysm dimensions, and procedural and follow‐up characteristics for each patient. For our analysis, the outcome was complete aneurysm occlusion, as reported by the studies. We performed a multivariable logistic regression to identify the predictors of complete occlusion. Next, we performed a mediation analysis framework to identify the causal relationship of the predictors with the outcome. Finally, we calculated the predicted probability of occlusion for the continuous predictors. Results A total of 348 patients with 348 aneurysms were included, 394 devices were implanted (1.13 per patient). Median age was 61 [22‐85] years, and 83.6% were females. Hypertension was the most common comorbidity (57%) followed by hyperlipidemia (36%). The ICA paraophthalmic segment was the most common location (45%), followed by the petrocavernous (29%) and supraclinoid (25%). Median aneurysm size was 7.5 [1‐29] mm, and neck size was 4.3 [1‐23] mm. At the final follow‐up, the complete occlusion rate was 73% (255/348). After adjusting for confounders and accounting for collinearity, the multivariable analysis identified aneurysm size (OR 0.89; 95% CI 0.85‐0.93;p< .001), procedural technical events (OR 0.31; 95% CI 0.15‐0.65;p = .002), and first device length (OR 0.98; 95% CI 0.96‐1.00;p = .036) as predictors of complete occlusion. Age had a non‐significant direct effect on complete occlusion (p = .091) but a significant indirect effect mediated through aneurysm size (p< .001) and technical events (p< .02). Using our model, the predicted probability of occlusion is≥ 75% in aneurysms measuring < 10 mm when no technical events are encountered. However, when technical events are encountered, the probability decreases to 50–75%. Conclusions Successful aneurysm occlusion after flow diversion is associated with aneurysm size, procedural technical events, and FD length. Age does not directly affect occlusion, but its influence is mediated through the aneurysm size and technical events. Therefore, a priori knowledge of the patient and aneurysm characteristics might guide FD selection to favor the best treatment outcomes

Safety and Efficacy of the Surpass Streamline for Intracranial Aneurysms (SESSIA): A Multi-Center US Experience Pooled Analysis

BACKGROUND AND PURPOSE: Flow diversion has established as standard treatment for intracranial aneurysms, the Surpass Streamline is the only FDA-approved braided cobalt/chromium alloy implant with 72-96 wires. We aimed to determine the safety and efficacy of the Surpass in a post-marketing large United States cohort. MATERIALS AND METHODS: This is a retrospective multicenter study of consecutive patients treated with the Surpass for intracranial aneurysms between 2018 and 2021. Baseline demographics, comorbidities, and aneurysm characteristics were collected. Efficacy endpoint included aneurysm occlusion on radiographic follow-up. Safety endpoints were major ipsilateral ischemic stroke or treatment-related death. RESULTS: A total of 277 patients with 314 aneurysms were included. Median age was 60 years, 202 (73%) patients were females. Hypertension was the most common comorbidity in 156 (56%) patients. The most common location of the aneurysms was the anterior circulation in 89% (279/314). Mean aneurysm dome width was 5.77 ± 4.75 mm, neck width was 4.22 ± 3.83 mm, and dome/neck ratio was 1.63 ± 1.26. Small-sized aneurysms were 185 (59%). Single device was used in 94% of the patients, mean number of devices per patient was 1.06. At final follow-up, complete obliteration rate was 81% (194/239). Major stroke and death were encountered in 7 (3%) and 6 (2%) cases, respectively. CONCLUSION: This is the largest cohort study using a 72-96 wire flow diverter. The Surpass Streamline demonstrated a favorable safety and efficacy profile, making it a valuable option for treating not only large but also wide-necked small and medium-sized intracranial aneurysms

Endovascular versus medical therapy in posterior cerebral artery stroke: role of baseline NIHSS and occlusion site.

Background: Acute ischemic stroke (AIS) with isolated posterior cerebral artery occlusion (iPCAO) lacks management evidence from randomized trials. We aimed to evaluate whether the association between endovascular treatment (EVT) and outcomes in iPCAO-AIS is modified by initial stroke severity (baseline NIHSS) and arterial occlusion site. Methods: Based on the multicenter, retrospective, case-control study of consecutive iPCAO-AIS patients (PLATO study), we assessed the heterogeneity of EVT outcomes compared to medical management (MM) for iPCAO, according to baseline NIHSS (≤6 vs. >6) and occlusion site (P1 vs. P2), using multivariable regression modelling with interaction terms. The primary outcome was the favorable shift of 3-month mRS. Secondary outcomes included excellent outcome (mRS 0-1), functional independence (mRS 0-2), symptomatic intracranial hemorrhage (sICH) and mortality. Results: From 1344 patients assessed for eligibility, 1,059 were included (median age 74 years, 43.7% women, 41.3% had intravenous thrombolysis), 364 receiving EVT and 695 MM. Baseline stroke severity did not modify the association of EVT with 3-month mRS distribution (pint=0.312), but did with functional independence (pint=0.010), with a similar trend on excellent outcome (pint=0.069). EVT was associated with more favorable outcomes than MM in patients with baseline NIHSS>6 (mRS 0-1: 30.6% vs. 17.7%, aOR=2.01, 95%CI=1.22-3.31; mRS 0-2: 46.1% vs. 31.9%, aOR=1.64, 95%CI=1.08-2.51), but not in those with NIHSS≤6 (mRS 0-1: 43.8% vs. 46.3%, aOR=0.90, 95%CI=0.49-1.64; mRS 0-2: 65.3% vs. 74.3%, aOR=0.55, 95%CI=0.30-1.0). EVT was associated with more sICH regardless of baseline NIHSS (pint=0.467), while the mortality increase was more pronounced in patients with NIHSS≤6 (pint=0.044, NIHSS≤6: aOR=7.95,95%CI=3.11-20.28, NIHSS>6: aOR=1.98,95%CI=1.08-3.65). Arterial occlusion site did not modify the association of EVT with outcomes compared to MM. Conclusion: Baseline clinical stroke severity, rather than the occlusion site, may be an important modifier of the association between EVT and outcomes in iPCAO. Only severely affected patients with iPCAO (NIHSS>6) had more favorable disability outcomes with EVT than MM, despite increased mortality and sICH

Abstract 233: First‐line Techniques for Endovascular Therapy of Primary Distal medium Vessel Occlusion Stroke: A Matched Analysis

Introduction Previous studies did not show a difference in terms of safety and efficacy among first‐line stent retriever (SR), contact aspiration (CA), or combined techniques for proximal large vessel occlusion strokes. However, the optimal reperfusion therapy in patients with primary distal medium vessel occlusion (DMVO) strokes is uncertain. We aimed to compare the clinical and procedural outcomes among first‐line SR, CA and combined techniques in patients with primary DMVO. Methods This is a retrospective analysis of a prospectively maintained database from 14 comprehensive stroke centers in the US and Europe. Patients were included if they had a primary DMVO stroke due to MCA‐M3/M4, ACA‐A1/A2‐3, or PCA‐P1/P2‐3 and underwent mechanical thrombectomy with first‐line SR, CA, or combined technique. The primary outcome was FPE defined as eTICI 2c/3 on the first pass. Secondary outcomes included mFPE defined as eTICI 2b/3 on the first pass, successful reperfusion defined as eTICI 2b/3 at the end of the procedure. Clinical outcomes included 90‐day mRS0‐1 and 90‐day mRS0‐2. Safety measures included procedural complications, symptomatic intracranial hemorrhage (sICH), and 90‐day mortality. The secondary analysis aimed to identify the procedural and clinical outcomes in 3 matched cohorts: (SR vs. CA), (SR vs. combined technique), and (CA vs. combined technique). Results A total of 365 patients were eligible for analysis; 38.1% were female, with a mean age of 69.3 years and a median NIHSS score of 11 [7‐18]. The first‐line SR group consisted of n=74 (20.3%), CA group n=142 (38.9%), and combined technique group n=149 (40.8%). Patients with first‐line SR or combined technique had a lower median NIHSS score, less frequent MCA‐M3 segment occlusion, and less usage of the rescue strategy compared to those with first‐line CA, P<0.05. Patients with first‐line CA had less frequent BGC usage and lower rates of FPE and procedural complications compared to first‐line SR or combined technique, P<0.05. Successful reperfusion at the end of the procedure was similar among the 3 groups (Figure). On multivariable analysis, there was no difference in terms of primary, secondary outcomes, or safety measures among the 3 first‐line techniques, except for higher procedural complications in patients who underwent the first‐line combined technique compared to those with first‐line CA (aOR 3.66, 95% CI [1.25‐10.75], P=0.02). The matched analyses did not show any difference in the primary outcome: (1) (SR, n=54 vs. CA, n=54) FPE; 31.5% vs. 26.9%, P=0.61, aOR 1.33, 95% CI [0.57‐3.11], P=0.52), (2) (SR, n=72 vs. combined technique, n=54) FPE; 37.5% vs. 31.9%, P=0.48, aOR 1.48, 95% CI [0.73‐3.03], P=0.28), and (3) (CA, n=109 vs. combined technique, n=109) FPE; 24.1% vs. 25.7%, P=0.78, aOR 0.94, 95% CI [0.50‐1.74], P=0.84). Similarly, there was no difference in terms of secondary outcomes and safety measures. Conclusion Our study suggests that in patients with primary DMVO, first‐line SR, CA, and combined techniques have a similar rate of FPE with no differences in final reperfusion or clinical outcomes. Randomized clinical trials are warrante