OBJECTIVE: The Contour Neurovascular System (CNS) is a novel intrasaccular flow-disrupting device for the treatment of intracranial aneurysms. This study presents the authors\' institutional experience and midterm follow-up results with this device.
UNASSIGNED: Seventy-six consecutive patients (mean ± SD age 58.9 ± 12.4 years) were treated with the CNS for 76 aneurysms (63 unruptured, 10 recurrent, and 3 ruptured). Aneurysm characteristics, procedural details, and clinical/angiographic outcomes were retrospectively evaluated.
RESULTS: The most common aneurysm locations were the basilar tip in 25 (32.9%) cases and the anterior communicating artery in 22 (28.9%). There were 18 (23.7%) sidewall aneurysms. The mean ± SD aneurysm width was 5.6 ± 2.5 mm, and 68 (89.5%) aneurysms were wide-necked. The CNS was successfully implanted in 68 (89.5%) aneurysms, with 11 cases of additional coiling and 1 case each of additional stent and balloon. There were 3 (3.9%) thromboembolic events, of which 1 (1.3%) was symptomatic (a major ischemic stroke) and resulted in morbidity. There were no hemorrhagic events or deaths. At last available follow-up (mean 12 months), 32/56 (57.1%) aneurysms were completely occluded, 16/56 (28.6%) had neck remnants, and 8/56 (14.3%) had an aneurysm remnant. Three (5.4%) aneurysms were retreated.
CONCLUSIONS: The use of the CNS was safe and feasible but proper aneurysm selection appears to be required, which may be facilitated with increasing operator experience and further study of this device. Similar to other intrasaccular flow disrupters, midterm complete occlusion rates are moderate but may increase with longer follow-up.

OBJECTIVE: Pipeline embolization device (PED) placement for the treatment of intracranial aneurysms is safe and effective under general anesthesia (GA). However, GA is associated with certain risks, longer procedural time, and higher hospital cost. The authors aimed to compare clinical outcomes and hospital cost between GA and local anesthesia (LA) procedures in patients who underwent PED placement for intracranial aneurysm treatment.
METHODS: This retrospective study analyzed the charts of 216 patients with 223 intracranial aneurysms treated using the PED from June 2022 to March 2023. Cases were grouped according to type of anesthesia administered (LA or GA). Propensity score matching (PSM) was used to balance the groups to minimize confounding bias.
RESULTS: Eighty-four patients with 88 aneurysms were treated under LA, and 132 patients with 135 aneurysms were treated under GA. The complication rate and modified Rankin Scale score at 6 months were similar in both groups. Procedural time was significantly shorter with LA both before (87.47 ± 22.68 minutes vs 118.90 ± 46.80 minutes, p < 0.001) and after (84.75 ± 16.77 minutes vs 110.02 ± 38.56 minutes, p < 0.001) PSM. LA eliminates the need for postanesthesia recovery. Hospital cost was significantly lower in the LA group both before ($30,820.74 ± $3216.93 vs $32,846.62 ± $4731.50, p = 0.001) and after ($30,127.83 ± $2763.12 vs $33,874.41 ± $3163.56, p = 0.002) PSM.
CONCLUSIONS: PED placement under LA can achieve satisfactory outcomes similar to those of PED placement under GA; however, the use of LA reduces procedural time and hospital cost.

OBJECTIVE: Anterior choroidal artery (AChA) aneurysms account for 2%-5% of all intracranial aneurysms. Treatment considerations include microsurgical clipping, flow diversion, or coiling with or without adjunctive devices. AChA aneurysms pose challenges in treatment due to the origination of the aneurysm from the origin or proximal segment of the AChA. The AChA is particularly susceptible to vasospasm and occlusion during treatment with devastating neurological deficits, including hemiparesis, hemianesthesia, lethargy, neglect, and hemianopia. In this study, the authors performed a meta-analysis to quantify the outcomes and complication rates across treatment modalities for AChA aneurysms and to identify risk factors reported in the literature.
METHODS: The authors performed a systematic review of AChA aneurysms treated with surgical clipping, endovascular coiling, or flow diversion and reported in the PubMed, Embase, Scopus, and Cochrane search databases. Single-arm meta-analyses of the selected outcomes were performed in RStudio.
RESULTS: Literature review yielded 25 studies that met the inclusion criteria. In total, 1627 patients were included in the analysis, with 554 males, 1009 females, and 64 unspecified. The rate of any complication in the full cohort was 11.6%, with a rate of ischemic complications of 5.5% and a favorable recovery rate of 90.3% of all patients treated. In total, 1064 patients underwent surgical clipping, 443 were treated with coiling, and 120 patients with flow diversion. In clipped patients, the rate of total surgical complications was 17.6%, with an ischemic complication rate of 9.4%. The rate of good functional recovery, defined on the basis of a Glasgow Outcome Scale score of 4-5 or modified Rankin Scale score of 0-2, was 88.0%, and complete obliteration was achieved in 84.5% of surgically clipped aneurysms. The complication rate in coiled patients was 10.3%, with an ischemic complication rate of 3.0%. Good functional recovery was achieved in 88.6% of coiled patients and complete aneurysm obliteration in 74.1%. Flow diversion resulted in a complication rate of 1.3%, with 0.7% rate of ischemic complications. Good functional recovery was achieved in 98.4% of patients and complete aneurysm obliteration in 79.0% in the flow diversion group. Aneurysm morphological features that impacted the complication rate were also identified to augment quantitative data and to help guide treatment selection for AChA aneurysms.
CONCLUSIONS: Flow diversion showed significantly lower total and ischemic complications and improved outcomes compared to clipping and coiling. There may be differences in outcomes between treatment types, especially when considering the varied patient presentations that guide treatment selection.

OBJECTIVE: Unruptured middle cerebral artery aneurysm (uMCAA) has traditionally been treated with open surgical clipping (SC). Endovascular treatments (EVTs) were designed to reduce surgical risks in these cases. Nevertheless, despite its potential benefits, many surgeons favor SC for uMCAA. This updated meta-analysis aimed to compare the safety, efficacy, and clinical outcomes of SC and EVT for uMCAA.
METHODS: The authors searched the Medline, Embase, and Cochrane Library databases according to the Cochrane and PRISMA guidelines. Eligible studies included those with ≥ 4 patients with uMCAA reporting comparative data of SC and EVT. The endpoints were the complete occlusion rate (Raymond class I and II), good clinical outcomes (modified Rankin Scale score ≤ 2 or Glasgow Outcome Scale score ≥ 4), procedure-related complications (further divided into major and minor), and mortality. The authors pooled OR with 95% CI values with a random-effects model. I2 statistics were used to assess heterogeneity, and sensitivity analysis was conducted to address high heterogeneity. Publication bias was assessed with funnel plot analysis and the Egger\'s test.
RESULTS: The analysis included data from 10 studies. Regarding the complete occlusion assessment, the comparative analysis revealed OR 0.17 (95% CI 0.08-0.40, p < 0.01), favoring SC. In terms of achieving good clinical outcomes, OR 0.44 (95% CI 0.20-0.97, p < 0.05) was determined, favoring SC. No differences regarding total procedure-related complications, major complications, or mortality were identified. However, a higher likelihood of minor complications was identified for EVT, with OR 4.68 (95% CI 2.01-10.92, p < 0.01).
CONCLUSIONS: This systematic review and meta-analysis identified a lower likelihood of complete occlusion at last follow-up and lower likelihood of good clinical outcomes in patients treated with EVT when compared with SC. Furthermore, a higher likelihood of minor complications was identified in patients who underwent EVT when compared with SC. The findings reinforce that, based on the currently available data, SC should be considered the primary approach for treating uMCAA. However, EVT is an evolving approach, and this study\'s findings represent a synthesis of observational studies. Randomized trials are warranted to elucidate which approach should be the mainstay for uMCAA and to identify the nuances that determine whether SC or EVT is more or less indicated for addressing uMCAA with consideration of the individuality of each patient and aneurysm.

OBJECTIVE: The paucity of literature comparing Woven EndoBridge (WEB) embolization to microsurgical clipping for anterior circulation wide-neck bifurcation aneurysms (WNBAs) underscores the need for further investigation into the optimal management of this patient subpopulation. The objective of this study was to compare the rate of endovascular and microsurgical treatment of WNBAs before and after the introduction of the WEB device. In addition, the authors performed a comparison of demographics, aneurysm characteristics, and treatment outcomes in patients before and after the introduction of the WEB device.
METHODS: This study was a retrospective review of the usage rate of different treatment modalities for WNBAs before and after the WEB device was approved by the US FDA on September 27, 2018.
RESULTS: The study cohort comprised 235 patients with anterior circulation WNBAs treated at the authors\' institution, including 127 aneurysms treated pre-WEB and 108 treated post-WEB. Generally, the rate of endovascular treatment of anterior circulation WNBAs was significantly higher post-WEB (86.1% vs 46.5%, p < 0.001), while the rate of clipping was significantly lower (13.9% vs 53.5%, p < 0.001). During follow-up, the rate of adequate aneurysm occlusion (Raymond-Roy occlusion classification [RROC] grades 1 and 2) was nonsignificantly higher in the post-WEB cohort (83.9% vs 78.5%, p = 0.34), while the rate of RROC grade 3 was nonsignificantly higher in the pre-WEB cohort (21.5% vs 16.1%, p = 0.34). Additionally, and although nonsignificant, the rates of recurrence (pre-WEB 25.3% vs post-WEB 14.9%, p = 0.12) and retreatment (pre-WEB 22.8% vs post-WEB 14.9%, p = 0.22) were higher in the pre-WEB cohort. Recurrence was assessed before retreatment.
CONCLUSIONS: After the introduction of the WEB device, the rate of endovascular treatment of WNBAs increased while the rate of microsurgical clipping decreased. It is essential for neurointerventionalists to become familiar with the indications, advantages, and shortcomings of all these different techniques to be able to match the right patient with the right technique to produce the best outcome.

OBJECTIVE: The aim of this study was to evaluate the morbidity associated with microsurgical treatment in patients with a recurrent aneurysm to improve their surgical management.
METHODS: From 2012 to 2022, among the 3128 patients with ruptured or unruptured intracranial aneurysms managed at the authors\' institution, 954 patients were treated by a microsurgical procedure. Of these 3128 patients, 60 consecutive patients (6.3%) who had a recurrent microsurgically treated aneurysm after previous endovascular treatment were included in this study. Additional microsurgical treatment was considered in case of progressive remnant growth or significant aneurysm recurrence. Intraoperative and postoperative complications were noted. Early (< 7 days) and long-term clinical and radiological monitoring were performed. Good functional outcome was considered as a modified Rankin Scale score < 3.
RESULTS: The mean age at initial treatment was 45 years (range 26-65 years). The mean delay between the first treatment and microsurgical treatment of the recurrence was 64 months (range 2 days-296 months). The mean size of the fundus recurrence was 5 mm, and the mean size of the neck recurrence was 4.6 mm. Five patients (8.3%) presented with subarachnoid hemorrhage associated with rupture of the recurrent aneurysm. Three patients died (6%) of aneurysm rupture and/or intensive care complications. The total morbidity rate associated with the microsurgical procedure was 14.5% (8/55) in patients with unruptured recurrent aneurysms. Among these patients, postoperative definitive complications (ischemic lesions) directly related to the microsurgical procedure were present in 3 patients (5.5%). Intraoperative rupture was recorded in these 3 patients. In the 54 surviving patients with unruptured recurrent aneurysms, good functional outcome was noted in 49 (91%). Poor functional outcome was significantly associated with intraoperative rupture.
CONCLUSIONS: Microsurgery remains an effective therapeutic option for recurrent intracranial aneurysms. However, in the authors\' experience, postoperative morbidity is higher than in patients with nonrecurrent aneurysms. Therefore, a pretherapeutic multidisciplinary evaluation is mandatory to reduce the potential morbidity associated with the retreatment as much as possible. When endovascular occlusion of the aneurysm requires both stenting and coiling, alternative microsurgical treatment should be carefully evaluated, as microsurgical clipping will become much more challenging in cases of aneurysm recurrence.

OBJECTIVE: The efficacy of endovascular thrombectomy in patients with posterior circulation ischemic stroke remains controversial. Early neurological deterioration (END) as an important predictor of poor outcome is poorly understood, except in cases of symptomatic intracranial hemorrhage, recanalization failure, and malignant cerebral edema. The objective of this study was to assess predictors of unexplained END (UnEND) after endovascular thrombectomy.
METHODS: The BASILAR study is a multicenter prospective observational study in which 647 patients with vertebrobasilar occlusion on imaging within 24 hours of stroke onset and who underwent endovascular treatment were enrolled, of whom 477 who had undergone successful recanalization were included in this study. Multivariate analysis was used to identify the predictors of UnEND, defined as a ≥ 4-point increase in National Institutes of Health Stroke Scale (NIHSS) score at 24 hours after endovascular thrombectomy.
RESULTS: Among the 477 eligible patients included, UnEND occurred in 86 (18%) patients. The predictors of UnEND were stress hyperglycemic ratio (SHR) (OR 2.2, 95% CI 1.1-4.6; p = 0.031), baseline NIHSS score (OR 0.9, 95% CI 0.83-0.95; p = 0.001), and asymptomatic intracerebral hemorrhage (aICH) (OR 5.9, 95% CI 1.7-20.0; p = 0.004). The occurrence rate of a favorable outcome, defined as a modified Rankin Scale score of 0-3 at 90 days, was lower in the UnEND group (5.8% vs 47.6%, p < 0.001) compared with the group without END, and the UnEND group had higher mortality at 90 days (66.3% vs 27.4%, p < 0.001).
CONCLUSIONS: UnEND may be associated with poor outcome after endovascular thrombectomy in patients with acute vertebrobasilar occlusion. Some modifiable factors such as SHR and aICH could be targeted to improve the efficacy of endovascular thrombectomy.

OBJECTIVE: Previous randomized controlled trials have reported a significantly higher occlusion rate of large and giant aneurysms when utilizing the Tubridge flow diverter (FD). In the present trial, the safety and efficacy of the Tubridge FD in treating unruptured internal carotid artery (ICA) or vertebral artery (VA) aneurysms were assessed in a real-world setting.
METHODS: The Intracranial Aneurysms Managed by Parent Artery Reconstruction Using Tubridge Flow Diverter (IMPACT) study is a prospective, multicenter, single-arm clinical trial assessing the efficacy of the Tubridge FD in the management of unruptured aneurysms located in the ICA or VA. The primary endpoint was the complete occlusion (Raymond-Roy class 1) rate at the 1-year follow-up. The secondary endpoints included the technical success rate, the successful occlusion rate of the aneurysm, which is the degree of aneurysm embolization scored as Raymond-Roy class 1 or 2, major (> 50%) in-stent stenosis, and incidence of disabling stroke or neurological death associated with the target aneurysms.
RESULTS: This study included 14 interventional neuroradiology centers, with 200 patients and 240 aneurysms. According to angiographic core laboratory assessment, 205 (85.4%) aneurysms were located in the ICA, 34 (14.2%) in the VA, and 1 (0.4%) in the middle cerebral artery. Additionally, 189 (78.8%) aneurysms were small (< 10 mm). At the 12-month follow-up, the total occlusion rate was 79.0% (166/210, 95% CI 72.91%-84.34%). Additionally, the occurrence of disabling stroke or neurological death related to the specified aneurysms was 1% (2/200).
CONCLUSIONS: The 1-year results from the IMPACT trial affirm the safety record of use of the Tubridge FD in the treatment of intracranial aneurysms in real-world scenarios. These results reveal low morbidity and mortality rates of 3.5% and 1.5%, respectively. Furthermore, they provide evidence of the effectiveness of the Tubridge FD, as demonstrated by the complete occlusion achieved in 166 of 210 (79%) cases.

OBJECTIVE: The placement of flow-diverting devices has become a common method of treating unruptured intracranial aneurysms of the internal carotid artery. The progressive improvement of aneurysm occlusion after treatment-with low complication and rupture rates-has led to a dilemma regarding the management of aneurysms in which occlusion has not occurred within 6-24 months. The authors aimed to identify clinical consensus regarding management of intracranial aneurysms displaying persistent filling 6-24 months after flow diversion and to ascertain questions that may drive future investigation.
METHODS: An international panel of 67 experts was invited to participate in a multistep Delphi consensus process on the treatment of intracranial aneurysms after failed flow diversion.
RESULTS: Of the 67 experts invited, 23 (34%) participated. Qualitative analysis of an initial survey with open-ended questions resulted in 51 statements regarding management of aneurysms showing persistent filling after flow diversion. The statements were grouped into 8 categories, and in the second round, respondents rated the degree of their agreement with each statement on a 5-point Likert scale. Flow diverters with surface modifiers did not influence administration of dual-antiplatelet therapy according to 83%. Consensus was also reached regarding the definition of treatment failure at specific time points, including at 6 months if there is aneurysm growth or persistent rapid flow through the entirety of the aneurysm (96%), at 12 months if there is aneurysm growth or symptom onset (78%), and at 24 months if there is persistent filling regardless of size and filling characteristics (74%). Although experts agreed that the degree of intimal hyperplasia or in-device stenosis could not be ascertained by noninvasive imaging alone (83%), only 65% chose digital subtraction angiography as the preferred modality. At 6 and 12 months, retreatment is preferred if there is persistent filling with aneurysm growth (96%, 96%), device malposition (48%, 87%), or a history of subarachnoid hemorrhage (65%, 70%), respectively, and at 24 months if there is persistent filling without reduction in aneurysm size (74%). Experts favored treatment with an additional flow diverter (87%) over aneurysm clipping, applying the same principles for follow-up (83%) and treatment failure (91%) as for the first flow diverter.
CONCLUSIONS: The authors present the consensus practices of experts in the management of intracranial aneurysms without occlusion 6-24 months after treatment with a flow-diverting device.

OBJECTIVE: The number of cerebrovascular (CV) surgeons has grown with the rise of endovascular neurosurgery. However, it is unclear whether the number of CV surgeon-scientists has concomitantly increased. With increasing numbers of CV neurosurgeons in the US workforce, the authors analyzed associated changes in National Institutes of Health (NIH) and Neurosurgery Research and Education Foundation (NREF) funding trends for CV surgeons over time.
METHODS: Publicly available data were collected on currently practicing academic CV surgeons in the US. Inflation-adjusted NIH funding between 2009 and 2021 was surveyed using NIH RePORTER and Blue Ridge Institute for Medical Research data. The K12 Neurosurgeon Research Career Development Program and NREF grant data were queried for CV-focused grants. Pearson R correlation, chi-square analysis, and the Mann-Whitney U-test were used for statistical analysis.
RESULTS: From 2009 to 2021, NIH funding increased: in total (p = 0.0318), to neurosurgeons (p < 0.0001), to CV research projects (p < 0.0001), and to CV surgeons (p = 0.0018). During this time period, there has been an increase in the total number of CV surgeons (p < 0.0001), the number of NIH-funded CV surgeons (p = 0.0034), and the percentage of CV surgeons with NIH funding (p = 0.370). Additionally, active NIH grant dollars per CV surgeon (p = 0.0398) and the number of NIH grants per CV surgeon (p = 0.4257) have increased. Nevertheless, CV surgeons have been awarded a decreasing proportion of the overall pool of neurosurgeon-awarded NIH grants during this time period (p = 0.3095). In addition, there has been a significant decrease in the number of K08, K12, and K23 career development awards granted to CV surgeons during this time period (p = 0.0024). There was also a significant decline in the proportion of K12 (p = 0.0044) and downtrend in early-career NREF (p = 0.8978) grant applications and grants awarded during this time period. Finally, NIH-funded CV surgeons were more likely to have completed residency less recently (p = 0.001) and less likely to have completed an endovascular fellowship (p = 0.044) as compared with non-NIH-funded CV surgeons.
CONCLUSIONS: The number of CV surgeons is increasing over time. While there has been a concomitant increase in the number of NIH-funded CV surgeons and the number of NIH grants awarded per CV surgeon in the past 12 years, there has also been a significant decrease in CV surgeons with K08, K12, and K23 career development awards and a downtrend in CV-focused K12 and early-career NREF applications and awarded grants. The latter findings suggest that the pipeline for future NIH-funded CV surgeons may be in decline.