Comparison of balloon guide catheter versus non-balloon guide catheter for mechanical thrombectomy in patients with distal medium vessel occlusion

BACKGROUND

Several studies have established the safety and efficacy of balloon guide catheters (BGCs) for large vessel occlusions. However, the utility of BGCs remains largely unexplored for distal medium vessel occlusions (DMVOs). In this study, we aim to compare the outcomes of BGC vs. Non-BGC in patients undergoing mechanical thrombectomy (MT) for DMVO.

METHOD

This retrospective study from the Stroke Thrombectomy and Aneurysm Registry (STAR) encompassed adult patients with acute anterior cerebral artery, posterior cerebral artery, and middle cerebral artery-M2-3-4 occlusions. Procedure times, safety, recanalization, and neurological outcomes were compared between the two groups, with subgroup analysis based on first-line thrombectomy techniques.

RESULTS

A total of 1508 patients were included, with 231 patients (15.3%) in the BGC group and 1277 patients (84.7%) in the non-BGC group. The BGC group had a lower modified Thrombolysis in Cerebral Infarction (mTICI) score ≥2C (43.2% vs 52.7%, P=0.01), longer time from puncture to intracranial access (15 vs 8 min, P<0.01), and from puncture to final recanalization (97 vs 34 min, P<0.01). In the Solumbra subgroup, the first pass effect (FPE) rate was lower in the BGC group (17.4% vs 30.7%, P=0.03). Regarding clinical outcomes, the BGC group had a lower rate of distal embolization (8.8% vs 14.9%, P=0.03).

CONCLUSION

Our study found that use of BGC in patients with DMVO was associated with lower mTICI scores, decreased FPE rates, reduced distal embolization, and longer procedure times.

A comprehensive review on the development of sporadic cerebral arteriovenous malformations: from Padget to next-generation sequencing

Cerebral arteriovenous malformations (AVMs) are a leading cause of intracerebral hemorrhage in both children and young adults. With the continued advancement of science and technology, the understanding of the pathophysiology behind the development of these lesions has evolved. From early theory published by Harvey Cushing and Percival Bailey in 1928, Tumors Arising from the Blood-vessels of the Brain: Angiomatous Malformations and Hemangioblastoma, which regarded AVMs as tumors arising from blood vessels, to the meticulous artistry of Dorcas Padget's embryological cataloguing of the cerebral vasculature in 1948, to the proliferative capillaropathy theory of Yaşargil in 1987, to Ramey's 2014 hierarchical model of vascular development, there have been multiple hypotheses of congenital, developmental, and genetic two-hit theories in the pathogenesis of AVMs. Most recent evidence implicates somatic KRAS mutations in the cerebral endothelium, producing an important understanding of the pathogenesis of this disease, which is critical to the development of targeted therapeutics. The authors present the historical progression of their understanding of AVM pathogenesis. They focus on the foundation laid by early pioneers, discussing embryological anatomy and vasculogenesis, the prominent theories of AVM development that have emerged over time, and culminate in an overview of the most current understanding of the pathogenesis of these complex vascular lesions and the clinical implications of our scientific progress.

Impact of Procedure Time on First Pass Effect in Mechanical Thrombectomy for Anterior Circulation Acute Ischemic Stroke

BACKGROUND AND OBJECTIVES

First pass effect (FPE) is a metric increasingly used to determine the success of mechanical thrombectomy (MT) procedures. However, few studies have investigated whether the duration of the procedure can modify the clinical benefit of FPE. We sought to determine whether FPE after MT for anterior circulation large vessel occlusion acute ischemic stroke is modified by procedural time (PT).

METHODS

A multicenter, international data set was retrospectively analyzed for anterior circulation large vessel occlusion acute ischemic stroke treated by MT who achieved excellent reperfusion (thrombolysis in cerebral infarction 2c/3). The primary outcome was good functional outcome defined by 90-day modified Rankin scale scores of 0-2. The primary study exposure was first pass success (FPS, 1 pass vs ≥2 passes) and the secondary exposure was PT. We fit-adjusted logistic regression models and used marginal effects to assess the interaction between PT (≤30 vs >30 minutes) and FPS, adjusting for potential confounders including time from stroke presentation.

RESULTS

A total of 1310 patients had excellent reperfusion. These patients were divided into 2 cohorts based on PT: ≤30 minutes (777 patients, 59.3%) and >30 minutes (533 patients, 40.7%). Good functional outcome was observed in 658 patients (50.2%). The interaction term between FPS and PT was significant ( P = .018). Individuals with FPS in ≤30 minutes had 11.5% higher adjusted predicted probability of good outcome compared with those who required ≥2 passes (58.2% vs 46.7%, P = .001). However, there was no significant difference in the adjusted predicted probability of good outcome in individuals with PT >30 minutes. This relationship appeared identical in models with PT treated as a continuous variable.

CONCLUSION

FPE is modified by PT, with the added clinical benefit lost in longer procedures greater than 30 minutes. A comprehensive metric for MT procedures, namely, FPE 30 , may better represent the ideal of fast, complete reperfusion with a single pass of a thrombectomy device.

Comparison between transradial and transfemoral mechanical thrombectomy for ICA and M1 occlusions: insights from the Stroke Thrombectomy and Aneurysm Registry (STAR)

BACKGROUND

The role for the transradial approach for mechanical thrombectomy is controversial. We sought to compare transradial and transfemoral mechanical thrombectomy in a large multicenter database of acute ischemic stroke.

METHODS

The prospectively maintained Stroke Thrombectomy and Aneurysm Registry (STAR) was reviewed for patients who underwent mechanical thrombectomy for an internal carotid artery (ICA) or middle cerebral artery M1 occlusion. Multivariate regression analyses were performed to assess outcomes including reperfusion time, symptomatic intracerebral hemorrhage (ICH), distal embolization, and functional outcomes.

RESULTS

A total of 2258 cases, 1976 via the transfemoral approach and 282 via the transradial approach, were included. Radial access was associated with shorter reperfusion time (34.1 min vs 43.6 min, P=0.001) with similar rates of Thrombolysis in Cerebral Infarction (TICI) 2B or greater reperfusion (87.9% vs 88.1%, P=0.246). Patients treated via a transradial approach were more likely to achieve at least TICI 2C (59.6% vs 54.7%, P=0.001) and TICI 3 reperfusion (50.0% vs 46.2%, P=0.001), and had shorter lengths of stay (mean 9.2 days vs 10.2, P<0.001). Patients treated transradially had a lower rate of symptomatic ICH (8.0% vs 9.4%, P=0.047) but a higher rate of distal embolization (23.0% vs 7.1%, P<0.001). There were no significant differences in functional outcome at 90 days between the two groups.

CONCLUSIONS

Radial and femoral thrombectomy resulted in similar clinical outcomes. In multivariate analysis, the radial approach had improved revascularization rates, fewer cases of symptomatic ICH, and faster reperfusion times, but higher rates of distal emboli. Further studies on the optimal approach are necessary based on patient and disease characteristics.

Metal allergy and neurovascular stenting: A systematic review

BACKGROUND

Intracranial stents and flow diverters contain significant amounts of metals, notably nickel, which can cause allergic reactions in a considerable portion of the population. These allergic responses may lead to complications like in-stent stenosis (ISS) and TIA/Stroke in patients receiving stents or flow diverters for intracranial aneurysms.

METHODS

We conducted a systematic review of studies from inception until July 2023, which reported outcomes of patients with metal allergy undergoing neurovascular stenting. The skin patch test was used to group patients into those with positive, negative, or absent patch test results but with a known history of metal allergy.

RESULTS

Our review included seven studies with a total of 39 patients. Among them, 87% had a history of metal allergy before treatment. Most aneurysms (89%) were in the anterior circulation and the rest (11%) were in the posterior circulation. Skin patch tests were performed in 59% of patients, with 24% showing positive results and 33% negative. Incidental ISS was observed in 18% of patients, and the rate of TIA/Stroke was reported in 21%. The pooled rates of ISS and TIA/Stroke were higher in the first group (43% and 38%) compared to the second (18% and 9%) and third groups (15% and 15%), but these differences were not statistically significant.

CONCLUSIONS

The current neurosurgical literature does not provide a conclusive association between metal allergy and increased complications among patients undergoing neurovascular stenting. Further studies are necessary to gain a more comprehensive understanding of this topic.

Effect of intravenous thrombolysis before endovascular therapy on outcomes in patients with large core infarct

BACKGROUND

The safety and efficacy of bridging therapy with intravenous thrombolysis (IVT) and mechanical thrombectomy (MT) in patients with large core infarct has not been sufficiently studied. In this study, we compared the efficacy and safety outcomes between patients who received IVT+MT and those treated with MT alone.

METHODS

This is a retrospective analysis of the Stroke Thrombectomy Aneurysm Registry (STAR). Patients with Alberta Stroke Program Early CT Score (ASPECTS) ≤5 treated with MT were included in this study. Patients were divided into two groups based on pre-treatment IVT (IVT, no IVT). Propensity score matched analysis were used to compare outcomes between groups.

RESULTS

A total of 398 patients were included; 113 pairs were generated using propensity score matching analyses. Baseline characteristics were well balanced in the matched cohort. The rate of any intracerebral hemorrhage (ICH) was similar between groups in both the full cohort (41.4% vs 42.3%, P=0.85) and matched cohort (38.55% vs 42.1%, P=0.593). Similarly, the rate of significant ICH was similar between the groups (full cohort: 13.1% vs 16.9%, P=0.306; matched cohort: 15.6% vs 18.95, P=0.52). There was no difference in favorable outcome (90-day modified Rankin Scale 0-2) or successful reperfusion between groups. In an adjusted analysis, IVT was not associated with any of the outcomes.

CONCLUSION

Pretreatment IVT was not associated with an increased risk of hemorrhage in patients with large core infarct treated with MT. Future studies are needed to assess the safety and efficacy of bridging therapy in patients with large core infarct.

Mechanical thrombectomy for large vessel occlusion strokes beyond 24 hours

BACKGROUND

Recent clinical trials have shown that mechanical thrombectomy is superior to medical management for large vessel occlusion for up to 24 hours from onset. Our objective is to examine the safety and efficacy of thrombectomy beyond the standard of care window.

METHODS

A retrospective review was undertaken of the multicenter Stroke Thrombectomy and Aneurysm Registry (STAR). We identified patients who underwent mechanical thrombectomy for large vessel occlusion beyond 24 hours. We selected a matched control group from patients who underwent thrombectomy in the 6-24-hour window. We used functional independence at 3 months as our primary outcome measure.

RESULTS

We identified 121 patients who underwent thrombectomy beyond 24 hours and 1824 in the 6-24-hour window. We selected a 2:1 matched group of patients with thrombectomy 6-24 hours as a comparison group. Patients undergoing thrombectomy beyond 24 hours were less likely to be independent at 90 days (18 (18.8%) vs 73 (34.9%), P=0.005). They had higher odds of mortality at 90 days in the adjusted analysis (OR 2.34, P=0.023). Symptomatic intracerebral hemorrhage and other complications were similar in the two groups. In a multivariate analysis only lower number of attempts was associated with good outcomes (OR 0.27, P=0.022).

CONCLUSIONS

Mechanical thrombectomy beyond 24 hours appears to be safe and tolerable with no more hemorrhages or complications compared with standard of care thrombectomy. Outcomes and mortality in this time window are worse compared with an earlier time window, but the rates of good outcomes may justify this therapy in selected patients.

Mechanical thrombectomy decision making and prognostication: Stroke treatment Assessments prior to Thrombectomy In Neurointervention (SATIN) study

BACKGROUND

Mechanical thrombectomy (MT) is the standard-of-care treatment for stroke patients with emergent large vessel occlusions. Despite this, little is known about physician decision making regarding MT and prognostic accuracy.

METHODS

A prospective multicenter cohort study of patients undergoing MT was performed at 11 comprehensive stroke centers. The attending neurointerventionalist completed a preprocedure survey prior to arterial access and identified key decision factors and the most likely radiographic and clinical outcome at 90 days. Post hoc review was subsequently performed to document hospital course and outcome.

RESULTS

299 patients were enrolled. Good clinical outcome (modified Rankin Scale (mRS) score of 0-2) was obtained in 38% of patients. The most frequently identified factors influencing the decision to proceed with thrombectomy were site of occlusion (81%), National Institutes of Health Stroke Scale score (74%), and perfusion imaging mismatch (43%). Premorbid mRS score determination in the hyperacute setting accurately matched retrospectively collected data from the hospital admission in only 140 patients (46.8%). Physicians correctly predicted the patient's 90 day mRS tertile (0-2, 3-4, or 5-6) and final modified Thrombolysis in Ischemic Cerebral Infarction score preprocedure in only 44.2% and 44.3% of patients, respectively. Clinicians tended to overestimate the influence of occlusion site and perfusion imaging on outcomes, while underestimating the importance of pre-morbid mRS.

CONCLUSIONS

This is the first prospective study to evaluate neurointerventionalists' ability to accurately predict clinical outcome after MT. Overall, neurointerventionalists performed poorly in prognosticating patient 90 day outcomes, raising ethical questions regarding whether MT should be withheld in patients with emergent large vessel occlusions thought to have a poor prognosis.

Milestones for neurosurgery sub-interns: a novel evaluation tool to quantitatively differentiate residency applicants

OBJECTIVE

The study objective was to create a novel milestones evaluation form for neurosurgery sub-interns and assess its potential as a quantitative and standardized performance assessment to compare potential residency applicants. In this pilot study, the authors aimed to determine the form's interrater reliability, relationship to percentile assignments in the neurosurgery standardized letter of recommendation (SLOR), ability to quantitatively differentiate tiers of students, and ease of use.

METHODS

Medical student milestones were either adapted from the resident Neurological Surgery Milestones or created de novo to evaluate a student's medical knowledge, procedural aptitude, professionalism, interpersonal and communication skills, and evidence-based practice and improvement. Four milestone levels were defined, corresponding to estimated 3rd-year medical student through 2nd-year resident levels. Faculty and resident evaluations as well as student self-evaluations were completed for 35 sub-interns across 8 programs. A cumulative milestone score (CMS) was computed for each student. Student CMSs were compared both within and between programs. Interrater reliability was determined with Kendall's coefficient of concordance (Kendall's W). Student CMSs were compared against their percentile assignments in the SLOR using analysis of variance with post hoc testing. CMS-derived percentile rankings were assigned to quantitatively distinguish tiers of students. Students and faculty were surveyed on the form's usefulness.

RESULTS

The average faculty rating overall was 3.20, similar to the estimated competency level of an intern. Student and faculty ratings were similar, whereas resident ratings were lower (p < 0.001). Students were rated most highly in coachability and feedback (3.49 and 3.67, respectively) and lowest in bedside procedural aptitude (2.90 and 2.85, respectively) in both faculty and self-evaluations. The median CMS was 26.5 (IQR 21.75-29.75, range 14-32) with only 2 students (5.7%) achieving the highest rating of 32. Programs that evaluated the most students differentiated the highest-performing students from the lowest by at least 13 points. A program with 3 faculty raters demonstrated scoring agreement across 5 students (p = 0.024). The CMS differed significantly between SLOR percentile assignments, despite 25% of students being assigned to the top fifth percentile. CMS-driven percentile assignment significantly differentiated the bottom, middle, and top third of students (p < 0.001). Faculty and students strongly endorsed the milestones form.

CONCLUSIONS

The medical student milestones form was well received and differentiated neurosurgery sub-interns both within and across programs. This form has potential as a replacement for numerical Step 1 scoring as a standardized, quantitative performance assessment for neurosurgery residency applicants.

Outcomes of mechanical thrombectomy in stroke patients with extreme large infarction core

BACKGROUND

Recent clinical trials have demonstrated that patients with large vessel occlusion (LVO) and large infarction core may still benefit from mechanical thrombectomy (MT). In this study, we evaluate outcomes of MT in LVO patients presenting with extremely large infarction core Alberta Stroke Program Early CT Score (ASPECTS 0-2).

METHODS

Data from the Stroke Thrombectomy and Aneurysm Registry (STAR) was interrogated. We identified thrombectomy patients presenting with an occlusion in the intracranial internal carotid artery (ICA) or M1 segment of the middle cerebral artery and extremely large infarction core (ASPECTS 0-2). A favorable outcome was defined by achieving a modified Rankin scale of 0-3 at 90 days post-MT. Successful recanalization was defined by achieving a modified Thrombolysis In Cerebral Ischemia (mTICI) score ≥2B.

RESULTS

We identified 58 patients who presented with ASPECTS 0-2 and underwent MT . Median age was 70.0 (59.0-78.0) years, 45.1% were females, and 202 (36.3%) patients received intravenous tissue plasminogen activator. There was no difference regarding the location of the occlusion (p=0.57). Aspiration thrombectomy was performed in 268 (54.6%) patients and stent retriever was used in 70 (14.3%) patients. In patients presenting with ASPECTS 0-2 the mortality rate was 4.5%, 27.9% had mRS 0-3 at day 90, 66.67% ≥70 years of age had mRS of 5-6 at day 90. On multivariable analysis, age, National Institutes of Health Stroke Scale on admission, and successful recanalization (mTICI ≥2B) were independently associated with favorable outcomes.

CONCLUSIONS

This multicentered, retrospective cohort study suggests that MT may be beneficial in a select group of patients with ASPECTS 0-2.

Predictors of devastating functional outcome despite successful basilar thrombectomy

BACKGROUND

Basilar thrombosis frequently leads to poor functional outcomes, even with good endovascular reperfusion. We studied factors associated with severe disability or death in basilar thrombectomy patients achieving revascularization.

METHODS

We retrospectively analyzed records from a health system's code stroke registry, including successful basilar thrombectomy patients from January 2017 to May 2023 who were evaluated with pretreatment computed tomography perfusion. The primary outcome was devastating functional outcome (90-day modified Rankin Scale [mRS] score 5-6). A multivariable logistic regression model was constructed to determine independent predictors of the primary outcome. The area under the receiver operator characteristics curve (AUC) was calculated for the model distinguishing good from devastating outcome.

RESULTS

Among 64 included subjects, with mean (standard deviation) age 65.6 (14.1) years and median (interquartile range) National Institutes of Health Stroke Scale (NIHSS) 18 (5.75-24.5), the primary outcome occurred in 28 of 64 (43.8%) subjects. Presenting NIHSS (odds ratio [OR] 1.08, 95% confidence interval [CI] 1.01-1.14, p = 0.02), initial glucose (OR 0.99, 95% CI 0.97-1.00, p < 0.05), and proximal occlusion site (OR 7.38, 95% CI 1.84-29.60, p < 0.01) were independently associated with 90-day mRS 5-6. The AUC for the multivariable model distinguishing outcomes was 0.81 (95% CI 0.70-0.92).

CONCLUSION

We have identified presenting stroke severity, lower glucose, and proximal basilar occlusion as predictors of devastating neurological outcome in successful basilar thrombectomy patients. These factors may be used in medical decision making or for patient selection in future clinical trials.

Mechanical thrombectomy for the treatment of primary and secondary anterior cerebral artery occlusions: insights from STAR

BACKGROUND

The safety and efficacy of mechanical thrombectomy (MT) for the treatment of acute anterior cerebral artery (ACA) occlusions have not clearly been delineated. Outcomes may be impacted based on whether the occlusion is isolated to the ACA (primary ACA occlusion) or occurs in conjunction with other cerebral arteries (secondary).

METHODS

We performed a retrospective review of the multicenter Stroke Thrombectomy and Aneurysm (STAR) database. All patients with MT-treated primary or secondary ACA occlusions were included. Baseline characteristics, procedural outcomes, complications, and clinical outcomes were collected. Primary and secondary ACA occlusions were compared using the Mann-Whitney U test and Kruskal-Willis test for continuous variables and the χ2 test for categorical variables.

RESULTS

The study cohort comprised 238 patients with ACA occlusions (49.2% female, median (SD) age 65.6 (16.7) years). The overall rate of successful recanalization was 75%, 90-day good functional outcome was 23%, and 90-day mortality was 35%. There were 44 patients with a primary ACA occlusion and 194 patients with a secondary ACA occlusion. When adjusted for baseline variables, the rates of successful recanalization (68% vs 76%, P=0.27), 90-day good functional outcome (41% vs 19%, P=0.38), and mortality at 90 days (25% vs 38%, P=0.12) did not differ between primary and secondary ACA occlusion groups.

CONCLUSION

Clinical and procedural outcomes are similar between MT-treated primary and secondary ACA occlusions for select patients. Our findings demonstrate the need for established criteria to determine ideal patient and ACA stroke characteristics amenable to MT treatment.

Technical and clinical outcomes in concurrent multivessel occlusions treated with mechanical thrombectomy: insights from the STAR collaboration

BACKGROUND

Endovascular thrombectomy (EVT) has become the mainstay treatment for large vessel occlusion, with favorable safety and efficacy profile. However, the safety and efficacy of EVT in concurrent multi-territory occlusions (MTVOs) remains unclear.

OBJECTIVE

To investigate the prevalence, clinical and technical outcomes of concurrent EVT for MTVOs.

METHODS

Data were included from the Stroke Thrombectomy and Aneurysm Registry (STAR) with 32 stroke centers for EVT performed to treat bilateral anterior or concurrent anterior and posterior circulation occlusions between 2017 and 2021. Patients with MTVO were identified, and propensity score matching was used to compare this group with patients with occlusion in a single arterial territory.

RESULTS

Of a total of 7723 patients who underwent EVT for acute ischemic stroke, 54 (0.7%) underwent EVT for MTVOs (mean age 69±12.5; female 50%). 28% had bilateral and 72% had anterior and posterior circulations occlusions. The rate of successful recanalization (Thrombolysis in Cerebral Infarction 2b/3), complications, modified Rankin score at 90 days, and mortality was not significantly different between the matched cohorts. Multivariate analysis confirmed that MTVOs were not associated with poor functional outcome, symptomatic intracranial hemorrhage, or longer procedure time.

CONCLUSION

Compared with EVT for single vessel occlusions, EVT in appropriately selected patients with MTVOs has a similar efficacy and safety profile.

Risk factors and predictors of intracranial hemorrhage after mechanical thrombectomy in acute ischemic stroke: insights from the Stroke Thrombectomy and Aneurysm Registry (STAR)

BACKGROUND

Reducing intracranial hemorrhage (ICH) can improve patient outcome in acute ischemic stroke (AIS) intervention. We sought to identify ICH risk factors after AIS thrombectomy.

METHODS

This is a retrospective review of the Stroke Thrombectomy and Aneurysm Registry (STAR) database. All patients who underwent AIS thrombectomy with available ICH data were included. Multivariable regression models were developed to identify predictors of ICH after thrombectomy. Subgroup analyses were performed stratified by symptom status and European Cooperative Acute Stroke Study (ECASS) grade.

RESULTS

The study cohort comprised 6860 patients. Any ICH and symptomatic ICH (sICH) occurred in 25% and 7% of patients, respectively. Hemorrhagic infarction 1 (HI1) occurred in 36%, HI2 in 24%, parenchymal hemorrhage 1 (PH1) in 22%, and PH2 in 17% of patients classified by ECASS grade. Intraprocedural complications independently predicted any ICH (OR 3.8083, P<0.0001), PH1 (OR 1.9053, P=0.0195), and PH2 (OR 2.7347, P=0.0004). Race also independently predicted any ICH (black: OR 0.5180, P=0.0017; Hispanic: OR 0.4615, P=0.0148), sICH (non-white: OR 0.4349, P=0.0107), PH1 (non-white: OR 3.1668, P<0.0001), and PH2 (non-white: OR 1.8689, P=0.0176), with white as the reference. Primary mechanical thrombectomy technique also independently predicted ICH. ADAPT (A Direct Aspiration First Pass Technique) was a negative predictor of sICH (OR 0.2501, P<0.0001), with stent retriever as the reference.

CONCLUSIONS

This study identified ICH risk factors after AIS thrombectomy using real-world data. There was a propensity towards a reduced sICH risk with direct aspiration. Procedural complications and ethnicity were predictors congruent between categories of any ICH, sICH, PH1, and PH2. Further investigation of technique and ethnicity effects on ICH and outcomes after AIS thrombectomy is warranted.

Blunt Cerebrovascular Injury: Are We Overscreening Low-Mechanism Trauma?

BACKGROUND AND PURPOSE

Screening patients with trauma for blunt cerebrovascular injury with neck CTA is a common practice, but there remains disagreement regarding which patients should be screened. We reviewed adult blunt cerebrovascular injury data from a level 1 trauma center to investigate whether screening is warranted in low-mechanism trauma.

MATERIALS AND METHODS

We reviewed all neck CTAs performed on adult trauma patients in the emergency department during the 2019 calendar year. Clinical and imaging risk factors for blunt cerebrovascular injury, trauma mechanism, initial neck CTA interpretations, results from subsequent CTA and DSA studies, antiplatelet and anticoagulant treatments, and outcome data were recorded.

RESULTS

One thousand one hundred thirty-six neck CTAs met the inclusion criteria, of which 965 (85%) were interpreted as having negative findings; 125, as having indeterminate findings (11%); and 46, as having positive findings (4%). Review of subsequent imaging and clinical documentation led to classification of 40 indeterminate studies (32%) as true-positives and 85 (68%) as false-positives. Blunt cerebrovascular injury was identified in 77 (12.6%) cases meeting and in 9 (1.7%) cases not meeting the expanded Denver criteria. The subset of 204 low-mechanism trauma cases (ground-level falls, blunt assaults, and low-impact motor vehicle collisions) not meeting the expanded Denver criteria (18% of the entire data set) could have been excluded from screening with 1 questionable injury and 0 ischemic strokes missed and 12 false-positive cases prevented.

CONCLUSIONS

We advocate reservation of blunt cerebrovascular injury screening in low-mechanism trauma for patients meeting the expanded Denver criteria. Further research is needed to determine the behavior of indeterminate cases and to establish criteria for separating true-positive from false-positive findings.

The Charlotte Large artery occlusion Endovascular therapy Outcome Score predicts independent outcome after thrombectomy

BACKGROUND AND PURPOSE

Predicting functional outcomes after endovascular thrombectomy (EVT) is of interest to patients and families as they navigate hospital and post-acute care decision-making. We evaluated the prognostic ability of several scales to predict good neurological function after EVT.

METHODS

We retrospectively analyzed records from a health system's code stroke registry, including consecutive successful thrombectomy patients from August 2020 to February 2023 presenting with an anterior circulation large vessel occlusion who were evaluated with pre-EVT CT perfusion. Primary and secondary outcomes were 90-day modified Rankin Scale (mRS) scores 0-2 and 0-1, respectively. Logistic regression was performed to evaluate the ability of each scale to predict the outcomes. Scales were compared by calculating the area under the curve (AUC).

RESULTS

A total of 465 patients (mean age 68.1 [±14.9] years, median National Institutes of Health Stroke Scale [NIHSS] 16 [11-21]) met inclusion criteria. In the logistic regression, the Charlotte Large artery occlusion Endovascular therapy Outcome Score (CLEOS), Totaled Health Risks in Vascular Events, Houston Intra-Arterial Therapy-2, Pittsburgh Response to Endovascular therapy, and Stroke Prognostication using Age and NIHSS were significant in predicting the primary and secondary outcomes. CLEOS was superior to all other scales in predicting 90-day mRS 0-2 (AUC .75, 95% confidence interval [CI] .70-.80) and mRS 0-1 (AUC .74, 95% CI .69-.78). Twenty of 22 patients (90.9%) with CLEOS <315 had 90-day mRS 0-2.

CONCLUSIONS

CLEOS predicts independent and excellent neurological function after anterior circulation EVT.

Comprehensive analysis of the impact of procedure time and the 'golden hour' in subpopulations of stroke thrombectomy patients

OBJECTIVE

To evaluate the effect of procedure time on thrombectomy outcomes in different subpopulations of patients undergoing endovascular thrombectomy (EVT), given the recently expanded indications for EVT.

METHODS

This multicenter study included patients undergoing EVT for acute ischemic stroke at 35 centers globally. Procedure time was defined as time from groin puncture to successful recanalization (Thrombolysis in Cerebral Infarction score ≥2b) or abortion of procedure. Patients were stratified based on stroke location, use of IV tissue plasminogen activator (tPA), Alberta Stroke Program Early CT score, age group, and onset-to-groin time. Primary outcome was the 90-day modified Rankin Scale (mRS) score, with scores 0-2 designating good outcome. Secondary outcome was postprocedural symptomatic intracranial hemorrhage (sICH). Multivariate analyses were performed using generalized linear models to study the impact of procedure time on outcomes in each subpopulation.

RESULTS

Among 8961 patients included in the study, a longer procedure time was associated with higher odds of poor outcome (mRS score 3-6), with 10% increase in odds for each 10 min increment. When procedure time exceeded the 'golden hour', poor outcome was twice as likely. The golden hour effect was consistent in patients with anterior and posterior circulation strokes, proximal or distal occlusions, in patients with large core infarcts, with or without IV tPA treatment, and across age groups. Procedures exceeding 1 hour were associated with a 40% higher sICH rate. Posterior circulation strokes, delayed presentation, and old age were the variables most sensitive to procedure time.

CONCLUSIONS

In this work we demonstrate the universality of the golden hour effect, in which procedures lasting more than 1 hour are associated with worse clinical outcomes and higher rates of sICH across different subpopulations of patients undergoing EVT.

A descriptive study of venous pressures and gradients while awake and both pre- and post-stent under anesthesia in patients with idiopathic intracranial hypertension

BACKGROUND

This study aims to explore factors that affect venous sinus pressures and associated gradients while awake and under general anesthesia (GA) both before and after venous sinus stenting (VSS) in patients with idiopathic intracranial hypertension (IIH).

METHODS

A retrospective analysis was performed examining pressures and gradients in patients with IIH having undergone awake venography followed by VSS under GA.

RESULTS

174 patients were included. Compared with awake, GA superior sagittal sinus (SSS) pressures were 2.6 mmHg lower (p=0.01) resulting in a total cranial gradient reduction of 2.5 mmHg (p=0.002). The transverse-sigmoid gradient, the most commonly stented segment, did not differ under the two conditions (p=0.30). Regression analyses demonstrated that body mass index, gender, blood pressure, and end-tidal carbon dioxide content significantly affected venous pressures (all p<0.05). After stenting, mean total cranial gradients decreased by 13.2 mmHg while skull base gradients increased by 0.8 mmHg. Stenting resulted in an 84% mean reduction in the target gradient and a mean decrease in SSS pressures by 78% of the target gradient. When cardiopulmonary and anesthetic factors were optimized, GA had a limited effect on the target gradient in most patients (p=0.88).

CONCLUSIONS

This study is the largest series to date to report on cerebral venous pressure measurements and gradients recorded while awake and under GA both before and after VSS for IIH. In a well-controlled cardiorespiratory and anesthetic setting, GA venography may provide information that is not substantially inequivalent to that obtained while awake.

Multicenter investigation of technical and clinical outcomes after thrombectomy for distal vessel occlusion by frontline technique

BACKGROUND

Endovascular thrombectomy (EVT) is the standard-of-care for proximal large vessel occlusion (LVO) stroke. Data on technical and clinical outcomes in distal vessel occlusions (DVOs) remain limited.

METHODS

This was a retrospective study of patients undergoing EVT for stroke at 32 international centers. Patients were divided into LVOs (internal carotid artery/M1/vertebrobasilar), medium vessel occlusions (M2/A1/P1) and isolated DVOs (M3/M4/A2/A3/P2/P3) and categorized by thrombectomy technique. Primary outcome was a good functional outcome (modified Rankin Scale ≤2) at 90 days. Secondary outcomes included recanalization, procedure-time, thrombectomy attempts, hemorrhage, and mortality. Multivariate logistic regressions were used to evaluate the impact of technical variables. Propensity score matching was used to compare outcome in patients with DVO treated with aspiration versus stent retriever RESULTS: We included 7477 patients including 213 DVOs. Distal location did not independently predict good functional outcome at 90 days compared with proximal (p=0.467). In distal occlusions, successful recanalization was an independent predictor of good outcome (adjusted odds ratio (aOR) 5.11, p<0.05) irrespective of technique. Younger age, bridging therapy, and lower admission National Institutes of Health Stroke Scale (NIHSS) were also predictors of good outcome. Procedure time ≤1 hour or ≤3 thrombectomy attempts were independent predictors of good outcomes in DVOs irrespective of technique (aOR 4.5 and 2.3, respectively, p<0.05). There were no differences in outcomes in a DVO matched cohort of aspiration versus stent retriever. Rates of hemorrhage and good outcome showed an exponential relationship to procedural metrics, and were more dependent on time in the aspiration group and attempts in the stent retriever group.

CONCLUSIONS

Outcomes following EVT for DVO are comparable to LVO with similar results between techniques. Techniques may exhibit different futility metrics; stent retriever thrombectomy was influenced by attempts whereas aspiration was more dependent on procedure time.

Predicting severe disability or death in endovascular thrombectomy with large computed tomography perfusion core infarction and limited penumbra

BACKGROUND

Patients presenting with large core infarctions benefit from treatment with endovascular thrombectomy (EVT), with a notable 50% reduction in rates of severe disability (modified Rankin Scale [mRS] 5) at 90 days. We studied the ability of previously reported prognostic scales to predict devastating outcomes in patients with a large ischemic core and limited salvageable brain tissue.

METHODS

Retrospective analysis from a health system's code stroke registry, including consecutive thrombectomy patients from November 2017 to December 2022 with an anterior circulation large vessel occlusion, computed tomography perfusion core infarct ≥ 50 ml, and mismatch volume < 15 ml or mismatch ratio < 1.8. Previously reported scales were compared using logistic regression and area under the curve (AUC) analyses to predict 90-day mRS 5-6.

RESULTS

Sixty patients (mean age 62.38 ± 14.25 years, median core volume 103 ml [74.75-153]) met inclusion criteria, of whom 27 (45%) had 90-day mRS 5-6. The Charlotte Large artery occlusion endovascular therapy Outcome Score (CLEOS) (odds ratio [OR] 1.35, 95% CI [1.14-1.60], p = 0.0005), Houston Intra-Arterial Therapy-2 (OR 1.35, 95% CI [1.00-1.83], p = 0.0470), and Totaled Health Risks in Vascular Events (OR 1.53, 95% CI [1.07-2.18], p = 0.0199) predicted the primary outcome in the logistic regression analysis. CLEOS performed best in the AUC analysis (AUC 0.83, 95% CI [0.72-0.94]).

CONCLUSION

CLEOS predicts devastating outcomes after EVT in patients with large core infarctions and small volumes of ischemic penumbra.

Incidence and outcome of perforations during medium vessel occlusion compared with large vessel occlusion thrombectomy

BACKGROUND

Vessel perforation during thrombectomy is a severe complication and is hypothesized to be more frequent during medium vessel occlusion (MeVO) thrombectomy. The aim of this study was to compare the incidence and outcome of patients with perforation during MeVO and large vessel occlusion (LVO) thrombectomy and to report on the procedural steps that led to perforation.

METHODS

In this multicenter retrospective cohort study, data of consecutive patients with vessel perforation during thrombectomy between January 1, 2015 and September 30, 2022 were collected. The primary outcomes were independent functional outcome (ie, modified Rankin Scale 0-2) and all-cause mortality at 90 days. Binomial test, chi-squared test and t-test for unpaired samples were used for statistical analysis.

RESULTS

During 25 769 thrombectomies (5124 MeVO, 20 645 LVO) in 25 stroke centers, perforation occurred in 335 patients (1.3%; mean age 72 years, 62% female). Perforation occurred more often in MeVO thrombectomy (2.4%) than in LVO thrombectomy (1.0%, p<0.001). More MeVO than LVO patients with perforation achieved functional independence at 3 months (25.7% vs 10.9%, p=0.001). All-cause mortality did not differ between groups (overall 51.6%). Navigation beyond the occlusion and retraction of stent retriever/aspiration catheter were the two most common procedural steps that led to perforation.

CONCLUSIONS

In our cohort, perforation was approximately twice as frequent in MeVO than in LVO thrombectomy. Efforts to optimize the procedure may focus on navigation beyond the occlusion site and retraction of stent retriever/aspiration catheter. Further research is necessary in order to identify thrombectomy candidates at high risk of intraprocedural perforation and to provide data on the effectiveness of endovascular countermeasures.

The Charlotte Large Artery Occlusion Endovascular Therapy Outcome Score Compares Favorably to the Critical Area Perfusion Score for Prognostication Before Basilar Thrombectomy

INTRODUCTION

The Critical Area Perfusion Score (CAPS) predicts functional outcomes in vertebrobasilar thrombectomy patients based on computed tomography perfusion (CTP) hypoperfusion. We compared CAPS to the clinical-radiographic Charlotte Large artery occlusion Endovascular therapy Outcome Score (CLEOS).

METHODS

Acute basilar thrombosis patients from January 2017-December 2021 were included in this retrospective analysis from a health system's stroke registry. Inter-rater reliability was assessed for 6 CAPS raters. A logistic regression with CAPS and CLEOS as predictors was performed to predict 90-day modified Rankin Scale (mRS) score 4-6. Area under the curve (AUC) analyses were performed to evaluate prognostic ability.

RESULTS

55 patients, mean age 65.8 (± 13.1) years and median NIHSS score 15.5^5-24, were included. Light's kappa among 6 raters for favorable versus unfavorable CAPS was 0.633 (95% CI 0.497-0.785). Increased CLEOS was associated with elevated odds of a poor outcome (odds ratio (OR) 1.0010, 95% CI 1.0007-1.0014, p<0.01), though CAPS was not (OR 1.0028, 95% CI 0.9420-1.0676, p=0.93). An overall favorable trend was observed for CLEOS (AUC 0.69, 95% CI 0.54-0.84) versus CAPS (AUC 0.49, 95% CI 0.34-0.64; p=0.051). Among 85.5% of patients with endovascular reperfusion, CLEOS had a statistically higher sensitivity than CAPS at identifying poor 90-day outcomes (71% versus 21%, p=0.003).

CONCLUSIONS

CLEOS demonstrated better predictive ability than CAPS for poor outcomes overall and in patients achieving reperfusion after basilar thrombectomy.

Abstract TMP16: Mechanoreceptor Dysregulation Found In Human Intracerebral Aneurysms

Introduction: About 500,000 people worldwide die annually from ruptured intracranial aneurysms (IA). The pathophysiology of aneurysm formation is largely unknown. Piezo1 mechanoreceptors are expressed in endothelial and smooth muscle cells of developing blood vessels. In addition to hemodynamic forces, Piezo1 has been shown to play an inflammatory role, as stiffness-sensing macrophages lacking Piezo1 exhibit reduced inflammation and enhanced wound healing responses. Malfunction of Piezo1 mechanoreceptors has been implicated in abdominal aortic aneurysm (AAA) development. With the increasing evidence of relationship between AAA and IAs, it is important to study Piezo1 dysregulation as a potential cause of IA development and/or rupture.

Methods: During craniotomy for aneurysm clipping of ruptured and unruptured IAs, we excised and collected the aneurysm dome in four patients. Immunohistochemistry (IHC) was performed for Piezo1 and with CD31 to co-localize Piezo1 in the endothelial cells, and a-SMA to co-localize in smooth muscle cells on all aneurysm domes. Additional specimen was saved for genomic analyses.

Results: Piezo1 mechanoreceptor overexpression was found in the smooth muscle layer of IAs, but not in superficial temporal artery (STA) controls, in all four human cerebral aneurysm domes. Additionally, there was significant dysregulation of Piezo1 mechanoreceptors in the IA compared with the regular appearance seen in the control human STA (Figure 1). Overexpression was not seen in human arteriovenous malformation specimens.

Conclusions: Our data is the first demonstration of overexpression of Piezo1 mechanoreceptors in a disorganized manner in the walls of human IAs, which may represent a therapeutic target. We hypothesize that vascular shear stress leads to Piezo1-mediated disorganization in arterial smooth muscle cells and pro-inflammatory activation, which may lead to IA development and rupture.

Transcranial ultrasonography to detect intracranial pathology: A systematic review and meta-analysis

BACKGROUND AND PURPOSE

Transcranial ultrasonography (TCU) can be a useful diagnostic tool in evaluating intracranial pathology in patients with limited or delayed access to routine neuroimaging in critical care or austere settings. We reviewed available literature investigating the diagnostic utility of TCU for detecting pediatric and adult patient's intracranial pathology in patients with intact skulls and reported diagnostic accuracy measures.

METHODS

We performed a systematic review of PubMed^® , Cochrane Library, Embase^® , Scopus^® , Web of Science™, and Cumulative Index to Nursing and Allied Health Literature databases to identify articles evaluating ultrasound-based detection of intracranial pathology in comparison to routine imaging using broad Medical Subject Heading sets. Two independent reviewers reviewed the retrieved articles for bias using the Quality Assessment of Diagnostic Accuracy Studies tools and extracted measures of diagnostic accuracy and ultrasound parameters. Data were pooled using meta-analysis implementing a random-effects approach to examine the sensitivity, specificity, and accuracy of ultrasound-based diagnosis.

RESULTS

A total of 44 studies out of the 3432 articles screened met the eligibility criteria, totaling 2426 patients (Mean age: 60.1 ± 14.52 years). We found tumors, intracranial hemorrhage (ICH), and neurodegenerative diseases in the eligible studies. Sensitivity, specificity, and accuracy of TCU and their 95% confidence intervals were 0.80 (0.72, 0.89), 0.71 (0.59, 0.82), and 0.76 (0.71, 0.82) for neurodegenerative diseases; 0.88 (0.74, 1.02), 0.81 (0.50, 1.12), and 0.94 (0.92, 0.96) for ICH; and 0.97 (0.92, 1.03), 0.99 (0.96, 1.01), and 0.99 (0.97, 1.01) for intracranial masses. No studies reported ultrasound presets.

CONCLUSIONS

TCU has a reasonable sensitivity and specificity for detecting intracranial pathology involving ICH and tumors with clinical applications in remote locations or where standard imaging is unavailable. Future studies should investigate ultrasound parameters to enhance diagnostic accuracy in diagnosing intracranial pathology.

Assessing opportunities for formal exposure to clinical neurosurgery within United States allopathic medical education curricula

OBJECTIVE

The objective of this study was to evaluate opportunities for early clinical exposure to neurosurgery at US allopathic medical schools and to assess associations between early exposure and recruitment into neurosurgery.

METHODS

The authors conducted a standardized review of online curriculum documentation for all US allopathic medical schools, including descriptive review of opportunities for clinical neurosurgical training among medical students. Chi-square analysis was used to compare baseline characteristics of institutions. Logistic regression was performed to assess factors predictive of early exposure to clinical neurosurgery, defined as completion of a formal rotation at least 6 months prior to Electronic Residency Application Service submission.

RESULTS

Among 155 allopathic US medical schools, 143 are fully accredited by the Liaison Committee on Medical Education. Eleven schools have no affiliated hospitals with a neurosurgery practice, and 26 do not have an American Association of Neurological Surgeons (AANS) medical student chapter. Overall, 94 (60.6%) have a traditional preclinical curriculum lasting 21-25 months, 50 (32.3%) offer an intermediate preclinical period of 15-20 months, and 11 (7.1%) report a short preclinical curriculum of 12-14 months. Early formal exposure to clinical neurosurgery was offered by 113 schools (72.9%). Early clinical exposure to neurosurgery was associated with a short (100%) or intermediate (76%) preclinical curriculum, as compared with a traditional curriculum (68.1%; p = 0.066). Early exposure was significantly associated with a shorter preclinical curriculum (OR 0.784, p = 0.005). AANS medical student chapters were present at a high majority of schools with early exposure (OR 4.114, p = 0.006). Medical schools with a higher percentage of graduating medical students matching into neurosurgery were associated with a shorter preclinical curriculum length (β = -0.287, p < 0.001), were more commonly private medical schools (β = 0.338, p < 0.001), and had early clinical exposure to neurosurgery (β = 0.191, p = 0.032).

CONCLUSIONS

Early exposure to clinical neurosurgery is available at most US allopathic medical schools and is associated with shorter preclinical curricula and institutions with AANS medical student chapters. Medical schools with a higher proportion of medical students entering neurosurgery had a shorter preclinical curriculum length and early clinical exposure to neurosurgery. Further study is recommended to characterize the impact of early exposure on long-term pedagogical outcomes.

Association of Noncontrast Computed Tomography and Perfusion Modalities With Outcomes in Patients Undergoing Late-Window Stroke Thrombectomy

IMPORTANCE

There is substantial controversy with regards to the adequacy and use of noncontrast head computed tomography (NCCT) for late-window acute ischemic stroke in selecting candidates for mechanical thrombectomy.

OBJECTIVE

To assess clinical outcomes of patients with acute ischemic stroke presenting in the late window who underwent mechanical thrombectomy stratified by NCCT admission in comparison with selection by CT perfusion (CTP) and diffusion-weighted imaging (DWI).

DESIGN, SETTING, AND PARTICIPANTS

In this multicenter retrospective cohort study, prospectively maintained Stroke Thrombectomy and Aneurysm (STAR) database was used by selecting patients within the late window of acute ischemic stroke and emergent large vessel occlusion from 2013 to 2021. Patients were selected by NCCT, CTP, and DWI. Admission Alberta Stroke Program Early CT Score (ASPECTS) as well as confounding variables were adjusted. Follow-up duration was 90 days. Data were analyzed from November 2021 to March 2022.

EXPOSURES

Selection by NCCT, CTP, or DWI.

MAIN OUTCOMES AND MEASURES

Primary outcome was functional independence (modified Rankin scale 0-2) at 90 days.

RESULTS

Among 3356 patients, 733 underwent late-window mechanical thrombectomy. The median (IQR) age was 69 (58-80) years, 392 (53.5%) were female, and 449 (65.1%) were White. A total of 419 were selected with NCCT, 280 with CTP, and 34 with DWI. Mean (IQR) admission ASPECTS were comparable among groups (NCCT, 8 [7-9]; CTP, 8 [7-9]; DWI 8, [7-9]; P = .37). There was no difference in the 90-day rate of functional independence (aOR, 1.00; 95% CI, 0.59-1.71; P = .99) after adjusting for confounders. Symptomatic intracerebral hemorrhage (NCCT, 34 [8.6%]; CTP, 37 [13.5%]; DWI, 3 [9.1%]; P = .12) and mortality (NCCT, 78 [27.4%]; CTP, 38 [21.1%]; DWI, 7 [29.2%]; P = .29) were similar among groups.

CONCLUSIONS AND RELEVANCE

In this cohort study, comparable outcomes were observed in patients in the late window irrespective of neuroimaging selection criteria. Admission NCCT scan may triage emergent large vessel occlusion in the late window.

Prognostic significance of age within the adolescent and young adult acute ischemic stroke population after mechanical thrombectomy: insights from STAR

OBJECTIVE

Although younger adults have been shown to have better functional outcomes after mechanical thrombectomy (MT) for acute ischemic stroke (AIS), the significance of this relationship in the adolescent and young adult (AYA) population is not well defined given its undefined rarity. Correspondingly, the goal of this study was to determine the prognostic significance of age in this specific demographic following MT for large-vessel occlusions.

METHODS

A prospectively maintained international multi-institutional database, STAR (Stroke Thrombectomy and Aneurysm Registry), was reviewed for all patients aged 12-18 (adolescent) and 19-25 (young adult) years. Parameters were compared using chi-square and t-test analyses, and associations were interrogated using regression analyses.

RESULTS

Of 7192 patients in the registry, 41 (0.6%) satisfied all criteria, with a mean age of 19.7 ± 3.3 years. The majority were male (59%) and young adults (61%) versus adolescents (39%). The median prestroke modified Rankin Scale (mRS) score was 0 (range 0-2). Strokes were most common in the anterior circulation (88%), with the middle cerebral artery being the most common vessel (59%). The mean onset-to-groin puncture and groin puncture-to-reperfusion times were 327 ± 229 and 52 ± 42 minutes, respectively. The mean number of passes was 2.2 ± 1.2, with 61% of the cohort achieving successful reperfusion. There were only 3 (7%) cases of reocclusion. The median mRS score at 90 days was 2 (range 0-6). Between the adolescent and young adult subgroups, the median mRS score at last follow-up was statistically lower in the adolescent subgroup (1 vs 2, p = 0.03), and older age was significantly associated with a higher mRS at 90 days (coefficient 0.33, p < 0.01).

CONCLUSIONS

Although rare, MT for AIS in the AYA demographic is both safe and effective. Even within this relatively young demographic, age remains significantly associated with improved functional outcomes. The implication of age-dependent stroke outcomes after MT within the AYA demographic needs greater validation to develop effective age-specific protocols for long-term care across both pediatric and adult centers.

Optimizing the residency application process: insights from neurological surgery during the pandemic virtual application cycle

OBJECTIVE

In this article, the authors describe the impact of the COVID-19 virtual match cycle and discuss approaches to optimize future cycles through applicant and neurosurgical education leadership insights.

METHODS

Anonymous surveys of neurosurgery program leaders (program directors and program chairs), program administrators (PAs), and 2020-2021 neurosurgery residency match applicants were distributed by the SNS, in conjunction with the Association of Resident Administrators in Neurological Surgery and AANS Young Neurosurgeons Committee.

RESULTS

Responses were received from 77 (67.0%) of 115 PAs, 119 (51.7%) of 230 program leaders, and 124 (44.3%) of 280 applicants representing geographically diverse regions. During the virtual application cycle relative to the previous year, programs received more Electronic Residency Application Service applications (mean 314.8 vs 285.3, p < 0.0001) and conducted more applicant interviews (mean 45.2 vs 39.9, p = 0.0003). More than 50% of applicants applied to > 80 programs; 60.3% received ≤ 20 interview invitations, and 9% received > 40 invitations. Overall, 65% of applicants completed ≤ 20 interviews, whereas 34.7% completed > 20 interviews. Program leaders described one 4-week home subinternship (93.3%) and two 4-week external subinternships (68.9%) as optimal neurosurgical exposure; 62.8% of program leaders found the standardized letter of recommendation template to be somewhat (47.5%) or significantly (15.3%) helpful. Applicants, PAs, and program leaders all strongly preferred a hybrid model of in-person and virtual interview options for future application cycles over all in-person or all virtual options. Ninety-three percent of applicants reported matching within their top 10-ranked programs, and 52.9% of programs matched residents within the same decile ranking as in previous years.

CONCLUSIONS

Optimizing a national strategy for the neurosurgery application process that prioritizes equity and reduces costs, while ensuring adequate exposure for applicants to gain educational opportunities and evaluate programs, is critical to maintain a successful training system.

Applying to residency: survey of neurosurgical residency applicants on virtual recruitment during COVID-19

OBJECTIVE

The COVID-19 pandemic caused a significant disruption to residency recruitment, including a sudden, comprehensive transition to virtual interviews. The authors sought to characterize applicant experiences and perceptions concerning the change in the application, interview, and match process for neurological surgery residency during the 2020-2021 recruitment cycle.

METHODS

A national survey of neurosurgical residency applicants from the 2020-2021 application cycle was performed. This survey was developed in cooperation with the Society of Neurological Surgeons (SNS) and the American Association of Neurological Surgeons Young Neurosurgeons Committee (YNC) and sent to all applicants (n = 280) who included academic video submissions to the SNS repository as part of their application package. These 280 applicants accounted for 69.6% of the total 402 neurosurgical applicants this year.

RESULTS

Nearly half of the applicants responded to the survey (44.3%, 124 of 280). Applicants favored additional reform of the interview scheduling process, including a centralized scheduling method, a set of standardized release dates for interview invitations, and interview caps for applicants. Less than 8% of students desired a virtual-only platform in the future, though the majority of applicants supported incorporating virtual interviews as part of the process to contain applicant costs and combining them with traditional in-person interview opportunities. Program culture and fit, as well as clinical and research opportunities in subspecialty areas, were the most important factors applicants used to rank programs. However, subjective program "fit" was deemed challenging to assess during virtual-only interviews.

CONCLUSIONS

Neurosurgery resident applicants identified standardized interview invitation release dates, centralized interview scheduling methods, caps on the number of interviews available to each candidate, and regulated opportunities for both virtual and in-person recruitment as measures that could significantly improve the applicant experience during and effectiveness of future neurosurgery residency application cycles. Applicants prioritized program culture and "fit" during recruitment, and a majority were open to incorporating virtual elements into future cycles to reduce costs while retaining in-person opportunities to gauge programs and their locations.

In Search of the Optimal Antithrombotic Regimen for Intracerebral Hemorrhage Survivors with Atrial Fibrillation

Spontaneous intracerebral hemorrhage (ICH) constitutes 10-15% of all strokes, and is a significant cause of mortality and morbidity. Survivors of ICH, especially those with atrial fibrillation (AF), are at risk for both recurrent hemorrhagic and ischemic cerebrovascular events. A conundrum in the field of vascular neurology, neurosurgery, and cardiology has been the decision to initiate or resume versus withhold anticoagulation in survivors of ICH with AF. To initiate anticoagulation would decrease the risk of ischemic stroke but may increase the risk of hemorrhage. To withhold anticoagulation maintains a lower risk of hemorrhage but does not decrease the risk of ischemic stroke. In this narrative review, we discuss the evidence for and against the use of antithrombotics in ICH survivors with AF, focusing on recently completed and ongoing clinical trials.

Efficacy of dural venous sinus stenting in treating idiopathic intracranial hypertension with acute vision loss

INTRODUCTION

Dural venous sinus stenting (VSS) is an effective, durable treatment for patients with idiopathic intracranial hypertension (IIH) due to underlying venous sinus stenosis. However, the use of venous sinus stenting to treat IIH with acute vision loss has rarely been described.

METHODS

A retrospective chart analysis identified patients who received VSS for fulminant IIH, defined as acute (< 8 weeks) visual field loss to within the central 5° and/or a decrease in visual acuity to less than or equal to 20/50 in either eye in the presence of papilledema.

RESULTS

Ten patients were identified with average patient age of 31.0 years, and all except one were female. Mean body mass index was 41.2 kg/m². All patients presented with vision loss and some with headache and tinnitus. The average trans-stenotic gradient pre-stenting was 28.7 mmHg (range 9-62 mmHg). All patients had diminished or resolved venous gradients immediately following the procedure. At mean follow-up of 60.5 weeks, 100% had improvements in papilledema, 80.0% had subjective vision improvement, 55.6% had headache improvement and 87.5% had tinnitus improvement. 90.0% had stable or improved visual acuity in both eyes with a mean post-stenting Snellen acuity of 20/30 and an average gain of 3 lines Snellen acuity post-stenting (95% confidence intervals 0.1185-0.4286, p = 0.0018). Two patients (20.0%) required further surgical treatment (cerebrospinal shunting and/or stenting) after their first stenting procedure.

CONCLUSIONS

This series suggests that VSS is feasible in patients presenting with IIH and acute vision loss with a fairly low complication rate and satisfactory clinical outcomes.

Is a picture-perfect thrombectomy necessary in acute ischemic stroke?

BACKGROUND

The benefit of complete reperfusion (modified Thrombolysis in Cerebral Infarction (mTICI) 3) over near-complete reperfusion (≥90%, mTICI 2c) remains unclear. The goal of this study is to compare clinical outcomes between mechanical thrombectomy (MT)-treated stroke patients with mTICI 2c versus 3.

METHODS

This is a retrospective study from the Stroke Thrombectomy and Aneurysm Registry (STAR) comprising 33 centers. Adults with anterior circulation arterial vessel occlusion who underwent MT yielding mTICI 2c or mTICI 3 reperfusion were included. Patients were categorized based on reperfusion grade achieved. Primary outcome was modified Rankin Scale (mRS) 0-2 at 90 days. Secondary outcomes were mRS scores at discharge and 90 days, National Institutes of Health Stroke Scale score at discharge, procedure-related complications, and symptomatic intracerebral hemorrhage.

RESULTS

The unmatched mTICI 2c and mTICI 3 cohorts comprised 519 and 1923 patients, respectively. There was no difference in primary (42.4% vs 45.1%; p=0.264) or secondary outcomes between the unmatched cohorts. Reperfusion status (mTICI 2c vs 3) was also not predictive of the primary outcome in non-imputed and imputed multivariable models. The matched cohorts each comprised 191 patients. Primary (39.8% vs 47.6%; p=0.122) and secondary outcomes were also similar between the matched cohorts, except the 90-day mRS which was lower in the matched mTICI 3 cohort (p=0.049). There were increased odds of the primary outcome with mTICI 3 in patients with baseline mRS ≥2 (36% vs 7.7%; p=0.011; pinteraction=0.014) and a history of stroke (42.3% vs 15.4%; p=0.027; pinteraction=0.041).

CONCLUSIONS

Complete and near-complete reperfusion after MT appear to confer comparable outcomes in patients with acute stroke.

The 2021 Neurosurgery Match: An analysis of the impact of virtual interviewing and other COVID-19 related changes

Given safety concerns during the COVID-19 pandemic, residency programs suspended away rotations in 2021 and the interview process transitioned to a virtual video format. In this study, we assessed the extent to which these changes affected match outcomes and if medical school ranking, international graduate status, or affiliation with a home neurosurgery program affected these outcomes. A cross-sectional analysis of neurosurgery match data from 2016-2021 was performed, and match outcomes were assessed based on matched program geography and program research ranking. Chi square tests were performed to identify significant differences between 2021 and 2016-2020 match results. A total of 1324 confirmed matched neurosurgery residents were identified from 2016-2021 (2016-2020: n=1113, 2021: n=211). There was no statistically significant difference in the rates of matching at a home program, within state, or within region between 2021 and 2016-2020 in the overall cohort. Proportions of international graduates and students without home programs among matched applicants were unchanged in 2021. In 2021, students from top 25 medical schools were less likely to match within their state or region (p<.05). Our findings may reflect an enhanced weighting given by programs to applicants from top medical schools in the absence of data from in-person rotations and interviews. These findings, coupled with the potential benefits of an increasingly virtual application process in improving equity and diversity among candidates from underrepresented communities, should be considered when determining permanent modifications to future residency application cycles.

Outcomes of Mechanical Thrombectomy for Patients With Stroke Presenting With Low Alberta Stroke Program Early Computed Tomography Score in the Early and Extended Window

IMPORTANCE

Limited data are available about the outcomes of mechanical thrombectomy (MT) for real-world patients with stroke presenting with a large core infarct.

OBJECTIVE

To investigate the safety and effectiveness of MT for patients with large vessel occlusion and an Alberta Stroke Program Early Computed Tomography Score (ASPECTS) of 2 to 5.

DESIGN, SETTING, AND PARTICIPANTS

This retrospective cohort study used data from the Stroke Thrombectomy and Aneurysm Registry (STAR), which combines the prospectively maintained databases of 28 thrombectomy-capable stroke centers in the US, Europe, and Asia. The study included 2345 patients presenting with an occlusion in the internal carotid artery or M1 segment of the middle cerebral artery from January 1, 2016, to December 31, 2020. Patients were followed up for 90 days after intervention. The ASPECTS is a 10-point scoring system based on the extent of early ischemic changes on the baseline noncontrasted computed tomography scan, with a score of 10 indicating normal and a score of 0 indicating ischemic changes in all of the regions included in the score.

EXPOSURE

All patients underwent MT in one of the included centers.

MAIN OUTCOMES AND MEASURES

A multivariable regression model was used to assess factors associated with a favorable 90-day outcome (modified Rankin Scale score of 0-2), including interaction terms between an ASPECTS of 2 to 5 and receiving MT in the extended window (6-24 hours from symptom onset).

RESULTS

A total of 2345 patients who underwent MT were included (1175 women [50.1%]; median age, 72 years [IQR, 60-80 years]; 2132 patients [90.9%] had an ASPECTS of ≥6, and 213 patients [9.1%] had an ASPECTS of 2-5). At 90 days, 47 of the 213 patients (22.1%) with an ASPECTS of 2 to 5 had a modified Rankin Scale score of 0 to 2 (25.6% [45 of 176] of patients who underwent successful recanalization [modified Thrombolysis in Cerebral Ischemia score ≥2B] vs 5.4% [2 of 37] of patients who underwent unsuccessful recanalization; P = .007). Having a low ASPECTS (odds ratio, 0.60; 95% CI, 0.38-0.85; P = .002) and presenting in the extended window (odds ratio, 0.69; 95% CI, 0.55-0.88; P = .001) were associated with worse 90-day outcome after controlling for potential confounders, without significant interaction between these 2 factors (P = .64).

CONCLUSIONS AND RELEVANCE

In this cohort study, more than 1 in 5 patients presenting with an ASPECTS of 2 to 5 achieved 90-day functional independence after MT. A favorable outcome was nearly 5 times more likely for patients with low ASPECTS who had successful recanalization. The association of a low ASPECTS with 90-day outcomes did not differ for patients presenting in the early vs extended MT window.

Bridging thrombolysis in atrial fibrillation stroke is associated with increased hemorrhagic complications without improved outcomes

BACKGROUND

Atrial fibrillation (AF) associated ischemic stroke is associated with worse functional outcomes, less effective recanalization, and increased rates of hemorrhagic complications after intravenous thrombolysis (IVT). Conversely, AF is not associated with hemorrhagic complications or functional outcomes in patients undergoing mechanical thrombectomy (MT). This differential effect of MT and IVT in AF associated stroke raises the question of whether bridging thrombolysis increases hemorrhagic complications in AF patients undergoing MT.

METHODS

This international cohort study of 22 comprehensive stroke centers analyzed patients with large vessel occlusion (LVO) undergoing MT between June 1, 2015 and December 31, 2020. Patients were divided into four groups based on comorbid AF and IVT exposure. Baseline patient characteristics, complications, and outcomes were reported and compared.

RESULTS

6461 patients underwent MT for LVO. 2311 (35.8%) patients had comorbid AF. In non-AF patients, bridging therapy improved the odds of good 90 day functional outcomes (adjusted OR (aOR) 1.29, 95% CI 1.03 to 1.60, p=0.025) and did not increase hemorrhagic complications. In AF patients, bridging therapy led to significant increases in symptomatic intracranial hemorrhage and parenchymal hematoma type 2 (aOR 1.66, 1.07 to 2.57, p=0.024) without any benefit in 90 day functional outcomes. Similar findings were noted in a separate propensity score analysis.

CONCLUSION

In this large thrombectomy registry, AF patients exposed to IVT before MT had increased hemorrhagic complications without improved functional outcomes, in contrast with non-AF patients. Prospective trials are warranted to assess whether AF patients represent a subgroup of LVO patients who may benefit from a direct to thrombectomy approach at thrombectomy capable centers.

Effect of Hispanic Status in Mechanical Thrombectomy Outcomes After Ischemic Stroke: Insights From STAR

Background and Purpose

Epidemiological studies have shown racial and ethnic minorities to have higher stroke risk and worse outcomes than non-Hispanic Whites. In this cohort study, we analyzed the STAR (Stroke Thrombectomy and Aneurysm Registry) database, a multi-institutional database of patients who underwent mechanical thrombectomy for acute large vessel occlusion stroke to determine the relationship between mechanical thrombectomy outcomes and race.

Methods

Patients who underwent mechanical thrombectomy between January 2017 and May 2020 were analyzed. Data included baseline characteristics, vascular risk factors, complications, and long-term outcomes. Functional outcomes were assessed with respect to Hispanic status delineated as non-Hispanic White (NHW), non-Hispanic Black (NHB), or Hispanic patients. Multivariate analysis was performed to identify variables associated with unfavorable outcome or modified Rankin Scale ≥3 at 90 days.

Results

Records of 2115 patients from the registry were analyzed. Median age of Hispanic patients undergoing mechanical thrombectomy was 60 years (72–84), compared with 63 years (54–74) for NHB, and 71 years (60–80) for NHW patients (P<0.001). Hispanic patients had a higher incidence of diabetes (41%; P<0.001) and hypertension (82%; P<0.001) compared with NHW and NHB patients. Median procedure time was shorter in Hispanics (36 minutes) compared to NHB (39 minutes) and NHW (44 minutes) patients (P<0.001). In multivariate analysis, Hispanic patients were less likely to have favorable outcome (odds ratio, 0.502 [95% CI, 0.263–0.959]), controlling for other significant predictors (age, admission National Institutes Health Stroke Scale, onset to groin time, number of attempts, procedure time).

Conclusions

Hispanic patients are less likely to have favorable outcome at 90 days following mechanical thrombectomy compared to NHW or NHB patients. Further prospective studies are required to validate our findings.

Abstract P150: Sex Differences In Augmentation Index And Aortic Pulse Pressure Among Patients Diagnosed With Acute Primary Intracerebral Hemorrhage

Introduction: Intracerebral hemorrhage (ICH) is the second most common subtype of stroke. Hypertension is a major cause of primary spontaneous ICH. However, sex difference in blood pressure (BP) and arterial stiffness among ICH patients is not well characterized.

Methods: A prospective pilot study to investigate the feasibility of measuring arterial stiffness in acute primary ICH patients was approved by the institutional research board at Wake Forest Baptist Health. Eligible subjects with primary ICH were enrolled in the study within 7 days of onset. Non-invasive measurements of brachial BP, aortic BP, augmentation index at heart rate of 75 beats per minute (AIx75), and carotid-femoral pulse wave velocity (cf-PWV) were measured at the patient’s bedside, using the SphygmoCor XCEL System v1 (AtCor Medical Pty Ltd., Sydney, Australia).

Results: A total of 20 patients have been enrolled in the study over 5 months. Over half the patients enrolled were female (55%, n = 11), including 82% (n = 9) White, 9% (n = 1) Asian and 9% (n = 1) Hispanic. There was increased diversity in the male patients (45%, n = 9) including 44% (n = 4) Black, 22% (n = 2) White, 22% (n = 2) Hispanic, and 11% (n = 1) Asian. Men were significantly younger than women (57 ± 5 years vs 74 ± 3 years, respectively, P = 0.009). There were no significant differences in BMI or ICH score. At the time of measurement, there were no significant sex differences in brachial or aortic blood pressures (systolic and diastolic), however, females had significantly higher AIx75 (35 ± 4 vs 20 ± 6, P = 0.036) and aortic PP (53 ± 2 mm Hg vs 42 ± 4 mm Hg, P = 0.020) than males. Sex difference in cf-PWV was not statistically significant (p = 0.054).

Conclusion: In the current feasibility pilot study, preliminary data show that females had higher arterial stiffness measured as AIx75 and aortic PP than males in the acute setting of ICH. Further study will be required to ascertain whether this is related to higher age at presentation in females. Whether sex differences in arterial stiffness predict differences in the outcome among ICH patients is not well characterized; thus, assessment of 30-day functional and neurological outcomes will be performed with NIHSS and modified Rankin Scores.

Trends in mechanical thrombectomy and decompressive hemicraniectomy for stroke: A multicenter study

BACKGROUND AND PURPOSE

Acute ischemic stroke has increasingly become a procedural disease following the demonstrated benefit of mechanical thrombectomy (MT) for emergent large vessel occlusion (ELVO) on clinical outcomes and tissue salvage in randomized trials. Given these data and anecdotal experience of decreased numbers of decompressive hemicraniectomies (DHCs) performed for malignant cerebral edema, we sought to correlate the numbers of strokes, thrombectomies, and DHCs performed over the timeline of the 2013 failed thrombolysis/thrombectomy trials, to the 2015 modern randomized MT trials, to post-DAWN and DEFUSE 3.

MATERIALS AND METHODS

This is a multicenter retrospective compilation of patients who presented with ELVO in 11 US high-volume comprehensive stroke centers. Rates of tissue plasminogen activator (tPA), thrombectomy, and DHC were determined by current procedural terminology code, and specificity to acute ischemic stroke confirmed by each institution. Endpoints included the incidence of stroke, thrombectomy, and DHC and rates of change over time.

RESULTS

Between 2013 and 2018, there were 55,247 stroke admissions across 11 participating centers. Of these, 6145 received tPA, 4122 underwent thrombectomy, and 662 patients underwent hemicraniectomy. The trajectories of procedure rates over time were modeled and there was a significant change in MT rate (p = 0.002) without a concomitant change in the total number of stroke admissions, tPA administration rate, or rate of DHC.

CONCLUSIONS

This real-world study confirms an increase in thrombectomy performed for ELVO while demonstrating stable rates of stroke admission, tPA administration and DHC. Unlike prior studies, increasing thrombectomy rates were not associated with decreased utilization of hemicraniectomy.

Predictors of Citations in Neurosurgical Research: A 5-Year Follow-Up

BACKGROUND

Citation rates are an important measure for the impact of articles. This study is the most comprehensive analysis of predictors for scientific neurosurgical research articles.

METHODS

Scientific articles published in 13 neurosurgical journals in 2015 were selected. Data collected included article subject, level of evidence (LOE), journal impact factor (IF), authorship, contributing centers, and study design. Citation counts were collected for each article in Web of Science (WoS) and Google Scholar (GS) 2.5 and 5 years after publication and Scopus 5 years after publication. A generalized linear mixed-effects model using the predictors of search engine, LOE, number of centers, number of authors, and IF was constructed to predict total citation count at 5 years.

RESULTS

A total of 2867 articles generated 39,190 citations in WoS, 61,682 in GS, and 43,481 in Scopus. The median number of citations per article was 10 (interquartile range [IQR], 14) in WoS, 15 (IQR, 20) in GS, and 11 (IQR, 15) in Scopus. On average, for every 1 citation in WoS, Scopus and GS identified 1.11 and 1.58 citations, respectively. Significant predictors of citation count in all databases 5 years after publication included search engine, LOE, number of centers, number of authors, number of countries, journal IF, and the month of publication (P < 0.05). The article subject (e.g., tumor or spine) did not significantly predict citation counts.

CONCLUSIONS

In the most thorough analysis of citation predictors in the neurosurgical literature, search engine, LOE, number of centers, number of authors, number of countries, journal impact factor, and month of publication influenced citations 5 years after publication.

The Use of Antiplatelet Agents and Heparin in the 24-Hour Postintravenous Alteplase Window for Neurointervention

BACKGROUND

Intravenous (IV) alteplase with mechanical thrombectomy has been found to be superior to alteplase alone in select patients with intracranial large vessel occlusion. Current guidelines discourage the use of antiplatelet agents or heparin for 24 h following alteplase. However, their use is often necessary in certain circumstances during thrombectomy procedures.

OBJECTIVE

To study the safety and outcomes in patients who received blood thinning medications for thrombectomy after IV Tissue-Type plasminogen activator (tPA).

METHODS

This is a multicenter retrospective review of the use of antiplatelet agents and/or heparin in patients within 24 h following tPA administration. Patient demographics, comorbidities, bleeding complications, and discharge outcomes were collected.

RESULTS

A series of 88 patients at 9 centers received antiplatelet medications and/or heparin anticoagulation following IV alteplase for revascularization procedures requiring stenting. The mean National Institutes of Health Stroke Scale (NIHSS) on admission was 14.6. Reasons for use of a stent included internal carotid artery occlusion in 74% of patients. Thrombolysis in cerebral infarction (TICI) 2b-3 revascularization was accomplished in 90% of patients. The rate of symptomatic intracranial hemorrhage (sICH) was 8%; this was not significantly different than the sICH rate for a matched group of patients not receiving antiplatelets or heparin during the same time frame. Functional independence at 90 d (modified Rankin Scale 0-2) was seen in 57.8% of patients. All-cause mortality was 12%.

CONCLUSION

The use of antiplatelet agents and heparin for stroke interventions following IV alteplase appears to be safe without significant increased risk of hemorrhagic complications in this group of patients when compared to control data and randomized controlled trials.

Alarming downtrend in mechanical thrombectomy rates in African American patients during the COVID-19 pandemic-Insights from STAR

BACKGROUND

The coronavirus disease (COVID-19) pandemic has affected stroke care globally. In this study, we aim to evaluate the impact of the current pandemic on racial disparities among stroke patients receiving mechanical thrombectomy (MT).

METHODS

We used the prospectively collected data in the Stroke Thrombectomy and Aneurysm Registry from 12 thrombectomy-capable stroke centers in the US and Europe. We included acute stroke patients who underwent MT between January 2017 and May 2020. We compared baseline features, vascular risk factors, location of occlusion, procedural metrics, complications, and discharge outcomes between patients presenting before (before February 2020) and those who presented during the pandemic (February to May 2020).

RESULTS

We identified 2083 stroke patients: of those 235 (11.3%) underwent MT during the COVID-19 pandemic. Compared with pre-pandemic, stroke patients who received MT during the pandemic had longer procedure duration (44 vs 38 min, P=0.006), longer length of hospitalization (6 vs 4 days, P<0.001), and higher in-hospital mortality (18.7% vs 11%, P<0.001). Importantly, there was a lower number of African American patients undergoing MT during the COVID-19 pandemic (609 (32.9%) vs 56 (23.8%); P=0.004).

CONCLUSION

The COVID-19 pandemic has affected the care process for stroke patients receiving MT globally. There is a significant decline in the number of African American patients receiving MT, which mandates further investigation.

Early Postmarket Results with EmboTrap II Stent Retriever for Mechanical Thrombectomy: A Multicenter Experience

BACKGROUND AND PURPOSE

EmboTrap II is a novel stent retriever with a dual-layer design and distal mesh designed for acute ischemic stroke emergent large-vessel occlusions. We present the first postmarket prospective multicenter experience with the EmboTrap II stent retriever.

MATERIALS AND METHODS

A prospective registry of patients treated with EmboTrap II at 7 centers following FDA approval was maintained with baseline patient characteristics, treatment details, and clinical/radiographic follow-up.

RESULTS

Seventy patients were treated with EmboTrap II (mean age, 69.9 years; 48.6% women). Intravenous thrombolysis was given in 34.3%, and emergent large-vessel occlusions were located in the ICA (n = 18), M1 (n = 38), M2 or M3 (n = 13), and basilar artery (n = 1). The 5 × 33 mm device was used in 88% of cases. TICI ≥ 2b recanalization was achieved in 95.7% (82.3% in EmboTrap II-only cases), and first-pass efficacy was achieved in 35.7%. The NIHSS score improved from a preoperative average of 16.3 to 12.1 postprocedure and to 10.5 at discharge. An average of 2.5 [SD, 1.8] passes was recorded per treatment, including non-EmboTrap attempts. Definitive treatment was performed with an alternative device (aspiration or stent retriever) in 9 cases (12.9%). Some hemorrhagic conversion was noted in 22.9% of cases, of which 4.3% were symptomatic. There were no device-related complications.

CONCLUSIONS

Initial postmarket results with the EmboTrap II stent retriever are favorable and comparable with those of other commercially available stent retrievers. Compared with EmboTrap II, the first-generation EmboTrap may have a higher first-pass efficacy; however, data are limited by retrospective case analysis, incomplete clinical follow-up, and small sample size, necessitating future trials.

Correlation between intracranial pressure and venous sinus pressures in patients undergoing cerebral venography and manometry

BACKGROUND

The pathophysiology of idiopathic intracranial hypertension (IIH) is complex but is directly related to cerebral venous hypertension. Few studies have simultaneously recorded venous sinus pressures and lumbar puncture (LP) opening pressure (OP) to understand the relationship between these factors without temporal confounding.

METHODS

A retrospective review was performed of patients with a known or suspected diagnosis of IIH who underwent cerebral venography with manometry followed immediately by LP.

RESULTS

47 patients aged 16-68 years met inclusion criteria. 91.5% were female. Mean body mass index (BMI) was 33.3 kg/m². Of the included patients, median OP was 21 cm H₂O (IQR (15.5, 26.5)). Mean (SD) recorded superior sagittal sinus (SSS) and torcular pressures were 25.5 (16.5) mm Hg and 23.8 (16.6) mm Hg, respectively. Twenty patients (42.6%) were discovered to have a trans-stenosis gradient of 8 mm Hg or greater. Transverse sinus, torcula, and SSS pressures were all significantly predicted by OP. On regression analysis, torcular pressures were best predicted by OP of the three measured sites. For 17 patients with OP <20 cm H₂O (36.2%), mean (SD) SSS and torcular pressures were 13.5 (4.2) mm Hg and 15.4 (6.7) mm Hg, respectively, suggesting that normally SSS pressures should measure <18 mm Hg (80th percentile) in non-pathologic conditions.

CONCLUSIONS

This is the first study to correlate venous sinus pressures and OP in patients with IIH with LP performed directly after manometry. In 47 patients, LP OP significantly predicted transverse sinus, torcula, and SSS pressures. Torcular pressures (mm Hg) were most accurately predicted by OP (cm H₂O) in a nearly one-to-one relationship.

Cerebral arteriopathy in ACTA2 mutations: a spectrum of disease highlighted by a case of variable penetrance in two siblings

Until recently, cerebral arteriopathy due to heterozygous mutations of the ACTA2 gene was considered a variant of moyamoya disease. However, radiographic analysis of patients with these mutations reveals a distinctive angiographic appearance from that seen in moyamoya disease. Several heterozygous missense ACTA2 mutations have been implicated in the development of this distinct cerebrovascular entity; however, the penetrance and systemic manifestations of these mutations vary based on the location of the amino acid replacement within the α-smooth muscle actin protein. The severity of the phenotype may also differ among patients within a single mutation type. There is limited literature on the safety and efficacy of revascularization procedures for ACTA2 arteriopathy, which have been limited to those patients with known Arg179His mutations. The authors provide a review of the breadth of mutations within the ACTA2 literature and report a case of two siblings with de novo ACTA2 Arg258Cys mutations with differing clinical courses, highlighting the utility of indirect revascularization with 8-year follow-up data. This case highlights the importance of early recognition of the angiographic appearance of ACTA2 cerebral arteriopathy and performance of genetic testing, as the location of the mutation impacts clinical presentation and outcomes.