Kallmes, David F.

Background Delayed aneurysm rupture (DAR) is a potentially devastating complication after flow-diverters (FD) deployment and their exact mechanisms are still unclear. The purpose of this meta-analysis is to synthesize the latest evidence on DAR after FD treatment and identify predictive factors. Methods A systematic review and meta-analysis were conducted according to established protocols. Searches were conducted in PubMed, Scopus, Web of Science, and Embase databases up to June 2024 using variations of “aneurysm “and “delayed aneurysm rupture” terms. Original studies reporting DAR and including more than five patients were included. All analyses were conducted in R software (version 4.4.2), employing the “meta” and “tableone” packages. Results 64 studies with 9820 patients were included, large aneurysm size (OR=1.08, 95% CI (1.02, 1.14), P value=0.008), intra-aneurysmal thrombus (OR=1.05, 95% CI (1.01, 1.09), P value=0.010) and posterior circulation location (OR=1.02, 95% CI (1.00, 1.04), P value=0.014) were significant risk factors for DAR. The pooled prevalence of DAR was 1.40%, with a rate of 1.18% after removing outliers. DAR occurred within 30 days in 66.7% of cases, with a mortality rate of 73.3% at discharge. Conclusion DAR following flow diversion treatment is an uncommon but devastating complication and remains a limitation of the technique. It is influenced by factors such as large aneurysm size, intra-aneurysmal thrombosis, and posterior circulation involvement. The first 30 days post-procedure represent a particularly high-risk period. Despite advancements in FD technology, significant gaps remain, highlighting the need for further research to improve risk assessment and treatment strategies.

Background Advancement in neurointervention is frequently driven by the introduction of new technology and devices that improve procedural efficacy and patient outcomes. For physician-innovators, customer discovery—or the process of directly engaging with end users to explore workflows and associated challenges—offers a structured way to identify meaningful problems and guide early innovation. This primer aims to outline stepwise guidance for conducting customer discovery within neurointervention to characterize key areas of unmet need. Methods We detail stepwise guidance for conducting customer discovery founded on foundational business literature. To illustrate this process, we conducted five interviews with expert neurointerventionalists engaged in clinical innovation. Interview transcripts were reviewed and analyzed to track emerging themes, and responses were synthesized into a neurointerventionalist customer profile. Results Responses from interviewed neurointerventionalists suggested that safer vascular access, tools to support treatment prognostication, and condition-specific device design are unmet areas of need. Moreover, interviews revealed broader concerns about stagnation in device innovation and barriers within regulatory and institutional pathways. Conclusions Structured customer discovery identifies unmet needs that may be overlooked when device development is solely driven by technical breakthroughs or published outcomes. By outlining an actionable framework for customer discovery in neurointervention, we provide a practical model for aligning future innovation with real-world clinical challenges.

Introduction Mechanical thrombectomy (MT) is a well‐established treatment for acute ischemic stroke (AIS) due to large vessel occlusion (LVO). However, its role in cervical artery dissection‐related (CeAD) LVO remains debated due to anatomical complexities and procedural challenges. This systematic review and meta‐analysis aims to evaluate the safety, efficacy, and clinical outcomes of MT in patients with AIS due to CeAD‐related LVO, compared with other AIS etiologies. Methods PubMed, Embase, and Scopus were systematically searched from inception through March 2025. Comparative observational studies evaluating the use of MT in adult patients with AIS due to LVO were included, specifically those comparing outcomes in those with CeAD versus non‐CeAD etiologies. Most studies were retrospective and multicentric. Eligible interventions included stent retriever thrombectomy, direct aspiration (ADAPT), or combined approaches. Results Nine studies with a total of 4889 patients were included, comprising 446 CeAD‐related and 4443 non‐CeAD LVO cases. MT for CeAD‐related AIS showed no statistically significant difference in successful recanalization compared with non‐CeAD cases (OR:0.81, CI: [0.63,1.04], p=0.10). However, CeAD patients had significantly higher rates of 90‐day functional independence (mRS 0‐2) (OR:2.17, CI: [1.55, 3.05], p < 0.0001) and lower 90‐day mortality (OR:0.34, CI: [0.22, 0.53], p < 0.0001). Rates of distal embolization (OR:1.60, CI: [0.69, 3.70], p = 0.27), symptomatic ICH (OR:0.84, CI: [0.51, 1.38], p=0.49), or iatrogenic dissection (OR:1.58, CI: [0.59, 4.22], p=0.36) did not differ significantly. Conclusions Mechanical thrombectomy in CeAD‐related LVO is safe and associated with clinical outcomes comparable to patients with non‐CeAD acute ischemic causes. They demonstrated a similar patient safety profile, such as functional outcomes and mortality.

Introduction Spontaneous intracranial hypotension (SIH) has been underdiagnosed, primarily due to limited clinical recognition and diagnostic capabilities. Recent improvements in diagnostic awareness and the implementation of advanced imaging techniques, notably targeted myelography and photon‐counting computed tomography (PCCT), have improved detection of cerebrospinal fluid‐venous fistulas (CSFVFs). We provide an updated SIH incidence within a defined U.S. County and quantify the proportional contribution of CSFVFs in this evolving diagnostic context. Methods We performed a retrospective, population‑based cohort study of adults evaluated for SIH from January 2019 through August 2025 at a quaternary referral center. Standard evaluation included brain MRI, whole‑spine MRI screening for spontaneous spinal CSF leaks (SLEC), and targeted myelography (lateral‑decubitus digital subtraction or dynamic CT/PCCT when available). Incident SIH was defined as the first imaging‑confirmed leak per patient. Incidence per 100,000 adult person‑years used adult population denominators with exact Poisson 95% CIs. Results We identified 33 incident SIH cases; 22/33 (66.7%) were CSFVF. Overall SIH incidence was 4.02 (95% CI 2.77‐5.65) per 100,000 person‑years; CSFVF‑specific incidence was 2.68 (95% CI 1.68‐4.06), 2.35 in women (95% CI 1.25‐4.02) and 1.50 in men (95% CI 0.65‐2.96). Significant upward trends were observed in annual incidence rates for SIH (Incidence Rate Ratio [IRR]: 1.23, 95% CI: 1.02‐1.48, p = 0.027) and specifically for CSFVFs (IRR: 1.29, 95% CI: 1.03‐1.63, p = 0.029). The symptom duration before diagnosis had a median of 4 months and appears to be shortening over time: 7 months in 2019‐2021 versus 4 months in 2022‐2025, consistent with faster recognition and targeted imaging. Conclusion The incidence of SIH, particularly due to CSFVFs, has increased significantly, likely attributable to improved clinical recognition and advanced imaging techniques rather than a true epidemiological shift. This highlights an urgent clinical message: maintain a high index of suspicion, image accordingly, and treat promptly. image image

Introduction For large vessel occlusion (LVO) ischemic strokes, three major techniques of mechanical thrombectomy have demonstrated efficacy. In this study, we compared stent retrievers (SR),contact aspiration (Asp), and a combined approach to provide an updated comparison of key outcomes for each strategy. Methods We followed PRISMA guidelines to conduct a systematic review and meta‐analysis across PubMed, EMBASE, Scopus, and Web of Science databases up to September 2024. Studies were included if they included outcomes for patients with ischemic stroke who underwent mechanical thrombectomy using a stent retriever, contact aspiration, or a combination of both techniques. Results Twenty‐four studies comprising a total of 12,845 patients were included in the analysis. Compared to the Asp technique alone, the combined mechanical thrombectomy (MT) approach was associated with a higher risk of arterial dissection (RR: 2.00; 95% CI [1.15, 3.44]), longer procedure duration (MD: 13.35 minutes; 95% CI [5.87, 20.83]) and associated with a lower risk of arterial dissection (RR: 0.50; 95% CI [0.29, 0.87]). However, Asp was associated with a lower rate of first‐pass effect (FPE) compared to combined MT (RR: 0.67; 95% CI [0.46, 0.96]). Additionally, stent retriever (SR) use was linked to a higher procedure duration compared to Asp(MD: 13.39 minutes; 95% CI [5.55, 21.22]) and a lower FPE rate (RR: 0.75; 95% CI [0.59,0.96]). No significant differences were observed between groups in terms of successful recanalization, 90‐day functional outcomes, or mortality. Conclusion In our analysis, all three techniques demonstrated similar recanalization rates and functional outcomes. However, aspiration was associated with shorter procedure times and fewer arterialdis section complications, while the combination technique showed a higher first pass effect. Given the comparable overall efficacy, the choice of technique should be guided by the physician's preference, expertise, and confidence, tailored to the individual patient's profile.

Background The Woven EndoBridge (WEB) device is an effective treatment for wide‐neck aneurysms (WNA). This study aims to identify and compare anatomical and procedural factors that predicts the aneurysm occlusion, both adequate and inadequate after WEB device treatment. Methods A systematic review and meta‐analysis were conducted using PubMed, Embase, Scopus, and Web of Science, including studies up to October 25, 2024. Data on angiographic outcomes of WEB occlusion were extracted and analyzed using R version 4.4.2 Results Nine studies (790 patients) were included. Female patients were 1.64 times more likely to achieve adequate occlusion than males (OR: 1.64, 95% CI: [1.06, 2.52], p = 0.026). Regular‐shaped aneurysms had a 2.44‐fold higher likelihood of adequate occlusion compared to irregular ones (OR: 0.41, 95% CI: [0.23, 0.74]). Aneurysm neck size was significantly smaller in the adequate occlusion group (3.9 mm vs. 4.4 mm, MD: ‐0.48 mm, 95% CI: [‐0.78, ‐0.18], p = 0.002). Maximum aneurysm diameter was also smaller in the adequate occlusion group (5.7 mm vs. 6.8 mm, MD: ‐1.13 mm, 95% CI: [‐1.69, ‐0.57], p < 0.001). Aneurysm height was also significantly lower than the inadequate occlusion group (5.4 mm vs. 6.3 mm, MD: ‐0.92 mm, 95% CI: [‐1.55, ‐0.29], p = 0.004). Conclusion Smaller aneurysm dimensions, regular shape, and female gender were associated with higher adequate occlusion rates after WEB treatment. These findings may guide patient selection strategies for optimizing aneurysm occlusion. Further high‐quality studies are needed to confirm these associations. image image

Background Mechanical thrombectomy (MT) is a well-established treatment for acute ischemic stroke (AIS) due to large vessel occlusion (LVO). However, its role in cervical artery dissection-related (CeAD) LVO remains debated due to anatomical complexities and procedural challenges. This systematic review and meta-analysis aims to evaluate the safety, efficacy, and clinical outcomes of MT in patients with AIS due to CeAD-related LVO compared with other AIS etiologies. Methods PubMed, Embase, and Scopus were systematically searched from inception to March 2025. Comparative observational studies evaluating the use of MT in adult patients with AIS due to LVO were included, specifically those comparing outcomes in patients with CeAD versus non-CeAD etiologies. Results MT for CeAD-related AIS showed no statistically significant difference in successful recanalization compared with non-CeAD cases (OR 0.81 (95% CI 0.63 to 1.04), P=0.10). However, patients with CeAD-related AIS had significantly higher rates of 90-day functional independence (modified Rankin Scale score 0–2) (OR 2.17 (95% CI 1.55 to 3.05), P<0.01) and lower 90-day mortality (OR 0.34 (95% CI 0.22 to 0.53), P<0.01). Rates of distal embolization (OR 1.60 (95% CI 0.69 to 3.70), P=0.27), symptomatic intracranial hemorrhage (OR 0.84 (95% CI 0.51 to 1.38), P=0.49), or iatrogenic dissection (OR 1.58 (95% CI 0.59 to 4.22), P=0.36) did not differ significantly between patient groups. Conclusions MT in patients with CeAD-related LVO is safe, effective, and associated with improved functional outcomes and lower mortality compared with patients with non-CeAD acute ischemic causes.

Background For large vessel occlusion (LVO) ischemic strokes, three major techniques of mechanical thrombectomy (MT) have demonstrated efficacy. Here we compare the safety and efficacy of stent retrievers (SR), contact aspiration (Asp), and a combined mechanical thrombectomy (cMT) for LVO ischemic stroke. Methods Using Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, we queried the PubMed, EMBASE, Scopus, and Web of Science databases for studies published prior to December 2024 describing patients with ischemic stroke who underwent MT using SR, Asp, or cMT. Results Twnety-four studies comprising a total of 12 845 patients were included in the analysis. Compared with cMT, Asp was associated with a lower rate of first pass effect (FPE) (risk ratio (RR) 0.67; 95% CI 0.46 to 0.96), shorter procedure duration (mean difference (MD) −13.35 min; 95% CI −20.83 to –5.87), and lower risk of arterial dissection (RR 0.50; 95% CI 0.29 to 0.87). Additionally, SR use was linked to a higher procedure duration compared with Asp (MD 13.39 min; 95% CI 5.55 to 21.22) and a lower symptomatic intracranial hemorrhage rate (RR 0.75; 95% CI 0.59 to 0.96). No significant differences were observed between groups in terms of number of passes, successful recanalization, 90-day functional outcomes, mortality, arterial perforation, or embolization to new territory. Conclusions All three techniques demonstrated similar recanalization rates and functional outcomes. However, Asp was associated with shorter procedure times and fewer arterial dissection complications, while cMT showed a higher FPE. Given the comparable overall efficacy, the choice of technique should be guided by the physician’s preference, expertise, and confidence, tailored to the individual patient’s profile.