Stroke emboli from patients with atrial fibrillation enriched with neutrophil extracellular traps.

Background: Recent literature has demonstrated remarkable heterogeneity in the composition of acute ischemic stroke (AIS) emboli, which may impact susceptibility to therapy. Objectives: In this study, we explored differences in proteomic composition of retrieved embolic material from patients with stroke with and without atrial fibrillation (AF) (AF+ and AF-, respectively). Methods: The full proteome of retrieved thromboembolic material from 24 patients with AIS was obtained by mass spectrometry. Known marker proteins were assigned groups representing broad classes of embolus components: red blood cells, platelets, neutrophils, eosinophils, histones, complement, and other clotting-associated proteins (eg, fibrinogen). Relative protein abundances were compared between AF+ and AF- samples. Functional implications of differences were explored with gene set enrichment analysis and Gene Ontology enrichment analysis and visualization tool. Results: One hundred sixty-six proteins were differentially expressed between AF+ and AF- specimens. Eight out of the 15 neutrophil proteins (P < .05; fold change, >2) and 4 of the 14 histone proteins were significantly enriched in AF+ emboli (P < .05; fold change, >2). Gene set enrichment analysis revealed a significant representation of proteins from published neutrophil extracellular trap (NET) proteomic gene sets. The most significantly represented functional Gene Ontology pathways in patients with AF involved neutrophil activation and degranulation (P < 1 × 10-7). Conclusion: The present analysis suggests enrichment of NETs in emboli of patients with stroke and AF. NETs are a significant though understudied structural component of thrombi. This work suggests not only unique stroke biology in AF but also potential therapeutic targets for AIS in this population.

Histone content, and thus DNA content, is associated with differential in vitro lysis of acute ischemic stroke clots.

BACKGROUND: Fibrin, von Willebrand factor, and extracellular DNA from neutrophil extracellular traps all contribute to acute ischemic stroke thrombus integrity. OBJECTIVES: In this study, we explored how the proteomic composition of retrieved thromboemboli relates to susceptibility to lysis with distinct thrombolytics. METHODS: Twenty-six retrieved stroke thromboemboli were portioned into 4 segments, with each subjected to 1 hour of in vitro lysis at 37 °C in 1 of 4 solutions: tissue plasminogen activator (tPA), tPA + von Willebrand factor-cleaving ADAMTS-13, tPA + DNA-cleaving deoxyribonuclease (DNase) I, and all 3 enzymes. Lysis, characterized by the percent change in prelysis and postlysis weight, was compared across the solutions and related to the corresponding abundance of proteins identified on mass spectrometry for each of the thromboemboli used in lysis. RESULTS: Solutions containing DNase resulted in approximately 3-fold greater thrombolysis than that with the standard-of-care tPA solution (post hoc Tukey, P < .01 for all). DNA content was directly related to lysis in solutions containing DNase (Spearman's ρ > 0.39 and P < .05 for all significant histones) and inversely related to lysis in solutions without DNase (Spearman's ρ < -0.40 and P < .05 for all significant histones). Functional analysis suggests distinct pathways associated with susceptibility to thrombolysis with tPA (platelet-mediated) or DNase (innate immune system-mediated). CONCLUSION: This study demonstrates synergy of DNase and tPA in thrombolysis of stroke emboli and points to DNase as a potential adjunct to our currently limited selection of thrombolytics in treating acute ischemic stroke.

Comparing Outcomes for Emergent Cranial Neurosurgical Procedures Performed "During Hours" and "After Hours".

OBJECTIVE: Surgery performed at night and on weekends is thought to be associated with increased complications. However, the impact of time of day on outcomes has not been studied within cranial neurosurgery. We aim to determine if there are differences in outcomes for cranial neurosurgery performed after hours (AH) compared with during hours (DH). METHODS: We performed a single-center retrospective study of cranial neurosurgery patients who underwent emergent surgery from January 2015 through December 2019. Surgery was considered DH if the incision occurred between 8 am and 5 pm Monday through Friday. We assessed outcome measures for differences between operations performed DH or AH. RESULTS: Three-hundred and ninety-three patients (114 DH, 279 AH) underwent surgery. There was a lower rate of return to the operating room within 30 days for AH (8.6%) compared with DH (14.0%), P = 0.03, on multivariate analysis. There were no significant differences in length of operation, estimated blood loss, improvement in Glasgow Coma Scale, intensive care unit and total hospital length of stay, 30-day readmission, 30-day mortality, and in-hospital mortality for cases performed DH compared with AH. Further subgroup analyses were performed for patients who underwent immediate surgery for subdural hematomas, with no differences noted in outcomes on multivariate analysis. CONCLUSIONS: This study suggests that operating AH does not appear to negatively impact outcomes when compared with operating DH, in cases of cranial neurosurgical emergencies. Further study assessing the impact on elective neurosurgical cases is required.

Safety and efficacy comparison of embolic agents for middle meningeal artery embolization for chronic subdural hematoma.

Objective: To perform a systematic review and meta-analysis evaluating the efficacy of middle meningeal artery embolization in terms of both clinical and radiographic outcomes, when performed with different embolic agents. Methods: A systematic literature review and meta-analysis was performed to evaluate the impact of embolic agents on outcomes for middle meningeal artery (MMA) embolization. The use of polyvinyl alcohol (PVA) with or without (±) coils, N-butyl cyanoacrylate (n-BCA) ± coils, and Onyx alone were separately evaluated. Primary outcome measures were recurrence, the need for surgical rescue and in-hospital periprocedural complications. Results: Thirty-one studies were identified with a total of 1,134 patients, with 786 receiving PVA, 167 receiving n-BCA, and 181 patients receiving Onyx. There was no difference in the recurrence rate (5.5% for PVA, 4.5% for n-BCA, and 6.5% for Onyx, with P=0.71) or need for surgical rescue (5.0% for PVA, 4.0% for n-BCA, and 6.9% for Onyx, with P=0.89) based on the embolic agent. Procedural complications also did not differ between embolic agents (1.8% for PVA, 3.6% for n-BCA, and 1.6% for Onyx, with P=0.48). Conclusions: Rates of recurrence, need for surgical rescue, and periprocedural complication following MMA embolization are not impacted by the type of embolic agent utilized. Ongoing clinical trials may be used to further investigate these findings.

A case of spontaneous basal ganglia hemorrhage with contralateral extension utilizing the canal of Gratiolet.

BACKGROUND: Intracranial hemorrhage accounts for 10-20% of stroke etiologies annually. Basal ganglia is the most common site for intracranial hemorrhage accounting for 50% of all cases. Bilateral spontaneous basal ganglia hemorrhages (BGH) are rare with few reported cases. CASE PRESENTATION: We report an unusual case of a 69-year-old female who presented with a spontaneous bilateral basal ganglia hemorrhage secondary to a right BGH with contralateral extension through the anterior commissure (AC) utilizing the Canal of Gratiolet. Clinical course and imaging findings are discussed. CONCLUSIONS: To our knowledge, this is the first case to specifically detail the extension of spontaneous hemorrhage across the AC via the Canal of Gratiolet, and imaging findings provide a novel depiction of AC anatomy and fiber distribution in a clinical context. These findings may explain the mechanism behind this rare clinical entity.

Ischemic stroke caused by spontaneous anterior circulation intracranial arterial dissections: patient series.

BACKGROUND: Intracranial arterial dissections (IADs) are classically associated with the vertebrobasilar system, yet are a devastating cause of ischemic stroke within the anterior circulation. Current literature regarding the surgical management of anterior circulation IAD is lacking. As a result, data on 9 patients presenting with ischemic stroke due to spontaneous anterior circulation IAD between 2019 and 2021 were collected in a retrospective manner. Symptoms, diagnostic modalities, treatment, and outcomes are presented for each case. Patients who underwent endovascular procedures had 10-minute follow-up angiography performed to identify signs of reocclusion, which prompted initiation of glycoprotein IIb/IIIa therapy and stent placement. OBSERVATIONS: Seven patients underwent emergent endovascular intervention (stenting: n = 5; thrombectomy alone: n = 2). The remaining 2 were managed medically. Two patients developed progressive flow limiting stenosis requiring further intervention, 2 developed asymptomatic progressive stenosis/occlusion with robust collateral formation and the remainder have patent vasculature upon follow up imaging at 6 to 12 months. Seven patients had a modified Rankin Scale score of 1 or less at the 3-month follow-up. LESSONS: IAD is a devastating yet rare cause of anterior circulation ischemic stroke. The treatment algorithm proposed resulted in positive clinical and angiographic outcomes warranting future consideration and study in the emergent management of spontaneous anterior circulation IAD.

Mechanical Thrombectomy for Ischemic Stroke Secondary to Large Vessel Occlusions in Patients on Extracorporeal Membrane Oxygenation.

INTRODUCTION: The use of short-term mechanical circulatory support (MCS) devices and procedures for function- and life-sustaining therapy is becoming a routine practice at many centers. Concomitant with the increasing use of MCS is the increasing recognition of acute brain injuries, including acute ischemic stroke, which may be caused by a myriad of MCS-driven factors. The aim of this case series was to document our experience with mechanical thrombectomy (MT) for ischemic stroke in extracorporeal membrane oxygenation (ECMO) patients. METHODS: We retrospectively reviewed a prospectively maintained database of patients undergoing endovascular thrombectomy for large vessel occlusion at our institution. We identified patients that were on ECMO and underwent thrombectomy. Baseline demographics and procedural and functional outcomes were collected. RESULTS: Three patients on ECMO were identified to have a large vessel occlusion and underwent thrombectomy. Two patients had an internal carotid artery terminus occlusion and one had a basilar artery occlusion. An mTICI 3 recanalization was achieved in all patients without postoperative hemorrhagic complications. Two patients achieved a 3-month mRS of 1, while one had mRS 4. CONCLUSION: Ischemic stroke can be associated with significant morbidity in MCS patients. We demonstrate that MT can be safely performed in this patient population with good outcomes.

Endovascular thrombectomy with or without intravenous thrombolysis in acute basilar artery occlusion ischemic stroke: A meta-analysis.

INTRODUCTION: It is poorly understood if endovascular thrombectomy (EVT) with or without intravenous thrombolysis (IVT) better facilitates clinical outcomes in patients with acute basilar artery occlusion (BAO) ischemic stroke. METHODS: A systematic literature review and meta-analysis was completed to investigate the outcomes of EVT with IVT versus direct EVT alone in acute BAO. Data was collected from the literature and pooled with the authors' institutional experience. The primary outcome measure was 90-day modified Rankin sale (mRS) of 0-2. Secondary measures were successful post-thrombectomy recanalization defined as mTICI ≥2b, 90-day mortality, and rate of symptomatic ICH. RESULTS: Our institutional experience combined with three multicenter studies resulted in a total of 1,127 patients included in the meta-analysis. 756 patients underwent EVT alone, while 371 were treated with EVT+IVT. Patients receiving EVT+IVT had a higher odds of achieving a 90-day mRS of ≤ 2 compared to EVT alone (OR: 1.50, 95% CI 1.15 to 1.95, P =0.002, I2 =0%). EVT+IVT also had a lower odds of 90-day mortality (OR: 0.57, 95% CI 0.37 to 0.89, P=0.01, I2=24%). There was no difference in sICH between the two groups (OR: 1.0, 95% CI: 0.56 to 1.79, P=0.99, I2=0%). There was also no difference in post-thrombectomy recanalization rates defined as mTICI ≥2b (OR: 1.11, 95% CI 0.70 to 1.75, P = 0.65, I2=37%). CONCLUSIONS: On meta-analysis, EVT with bridging IVT results in superior 90-day functional outcomes and lower 90-day mortality without increase in symptomatic ICH. These findings likely deserve further validation in a randomized controlled setting.

Observation versus intervention for Borden type I intracranial dural arteriovenous fistula: A pooled analysis of 469 patients.

BACKGROUND: While it is thought that Borden Type I intracranial dural arteriovenous fistula (dAVF) have a benign clinical course, their management remains controversial. METHODS: A comparative meta-analysis was completed to evaluate the outcomes of intervention verses observation of Borden Type I intracranial dAVF. Outcome measures included: grade progression, worsening symptoms, death due to dAVF, permanent complications other than death, functional independence (mRS 0-2), and rate of death combined with permanent complication, were evaluated. Risk differences (RD) were determined using a random effects model. RESULTS: Three comparative studies combined with the authors' institutional experience resulted in a total of 469 patients, with 279 patients who underwent intervention and 190 who were observed. There was no significant difference in dAVF grade progression between the intervention and observation arms, 1.8% vs. 0.7%, respectively (RD: 0.01, 95% CI: -0.02 to 0.04, P = 0.49), or in symptom progression occurring in 31/279 (11.1%) intervention patients and 11/190 (5.8%) observation patients (RD: 0.03, CI: -0.02 to 0.09, P = 0.28). There was also no significant difference in functional independence on follow up. However, there was a significantly higher risk of dAVF related death, permanent complication from either intervention or dAVF related ICH or stroke in the intervention group (11/279, 3.9%) compared to the observation group (0/190, 0%) (RD: 0.04, CI: 0.1 to 0.06, P = 0.007). CONCLUSION: Intervention of Borden Type I dAVF results in a higher risk of death or permanent complication, which should be strongly considered when deciding on management of these lesions.

High-fidelity, simulation-based microsurgical training for neurosurgical residents.

OBJECTIVE: Simulation is increasingly recognized as an important supplement to operative training. The live rat femoral artery model is a well-established model for microsurgical skills simulation. In this study, the authors present an 11-year experience incorporating a comprehensive, longitudinal microsurgical training curriculum into a Canadian neurosurgery program. The first goal was to evaluate training effectiveness, using a well-studied rating scale with strong validity. The second goal was to assess the impact of the curriculum on objective measures of subsequent operating room performance during postgraduate year (PGY)-5 and PGY-6 training. METHODS: PGY-2 neurosurgery residents completed a 1-year curriculum spanning 17 training sessions divided into 5 modules of increasing fidelity. Both perfused duck wing and live rat vessel training models were used. Three modules comprised live microvascular anastomosis. Trainee performance was video recorded and blindly graded using the Objective Structured Assessment of Technical Skills Global Rating Scale. Eleven participants who completed the training curriculum and 3 subjects who had not participated had their subsequent operative performances evaluated when they were at the PGY-5 and PGY-6 levels. RESULTS: Eighteen participants completed 106 microvascular anastomoses during the study. There was significant improvement in 6 measurable skills during the curriculum. The mean overall score was significantly higher on the fifth attempt compared with the first attempt for all 3 live anastomotic modules (p < 0.001). Each module had a different improvement profile across the skills assessed. Those who completed the microvascular skills curriculum demonstrated a greater number of independent evaluations during superficial surgical exposure, deep exposure, and primary maneuvers at the PGY-5 and PGY-6 levels. CONCLUSIONS: High-fidelity microsurgical simulation training leads to significant improvement in microneurosurgical skills. Transfer of acquired skills to the operative environment and durability for at least 3 to 4 years show encouraging preliminary results and are subject to ongoing investigation.

Approaches to and outcomes of intra-arterial tPA in embolectomy for large vessel occlusion.

INTRODUCTION: Intra-arterial tissue plasminogen activator (IA tPA) is sometimes used in conjunction with aspiration catheters and stentrievers to achieve recanalization in endovascular thrombectomy (ET) for large vessel occlusion (LVO). Reports of safety and efficacy of this approach are limited by technical heterogeneity and sample size. METHODS: We retrospectively reviewed a data set of patients undergoing ET for LVO between August 2017 and September 2020 to identify those that received IA tPA. IA tPA usage, timing and dosage was at the discretion of the operative neurosurgeon. We identified three broad categories of IA tPA administration: (1) adjunctive with the first pass; (2) salvage with subsequent passes after first pass achieved incomplete revascularization; and (3) post-thrombectomy residual distal occlusions. Univariate and multivariate logistic regression were performed to test associations with recanalization, hemorrhage, and functional independence. RESULTS: Among 271 patients, 158 (58%) patients had IA tPA, of which 83 received adjuvant IA tPA, 60 received salvage IA tPA, and 15 received post-thrombectomy IA tPA for distal occlusions. There were no differences in demographics, stroke etiology and premorbid medications between these groups. Patients receiving salvage IA tPA had longer times from groin access to recanalization and more passes, as expected. On multivariate analysis neither adjunctive nor salvage IA tPA was significantly associated with recanalization, post-operative hemorrhage, or functional outcomes. On univariate analysis, patients receiving salvage IA tPA had lower rates of TICI 3 or 2b revascularization (80% vs. 89% adjunctive and 92% no IA tPA, p =  0.003) and higher rates of any postoperative hemorrhage (33% vs. 22% adjunctive and 19% no IA tPA, p =  0.003). CONCLUSIONS: In this retrospective, single-institution series, IA tPA used adjunctively or as salvage therapy in ET for LVO was not associated with recanalization, post-operative hemorrhage, or functional outcomes, suggesting IA tPA is an available modality that can be utilized in cases of recalcitrant clots.

The Complex Relationship Between Cooling Parameters and Neuroprotection in a Model of Selective Hypothermia.

Background: Hypothermia remains the best studied neuroprotectant. Despite extensive positive large and small animal data, side effects continue to limit human applications. Selective hypothermia is an efficient way of applying neuroprotection to the brain without the systemic complications of global hypothermia. However, optimal depth and duration of therapeutic hypothermia are still unknown. We analyzed a large animal cohort study of selective hypothermia for statistical relationships between depth or duration of hypothermia and the final stroke volume. Methods: A cohort of 30 swine stroke subjects provided the dataset for normothermic and selective hypothermic animals. Hypothermic parameters including duration, temperature nadir, and an Area Under the Curve measurement for 34 and 30°C were correlated with the final infarct volumes measured by MRI and histology. Results: Between group comparisons continue to demonstrate a reduction in infarct volume with selective hypothermia. Histologically-derived infarct volumes were 1.2 mm3 smaller in hypothermia-treated pigs (P = 0.04) and showed a similar, but non-significant reduction in MRI (P = 0.15). However, within the selective hypothermia group, more intense cooling, as measured through increased AUC 34 and decreased temperature nadir was associated with larger infarct proportions by MRI [Pearson's r = 0.48 (p = 0.05) and r = -0.59 (p = 0.01), respectively]. Reevaluation of the entire cohort with quadratic regression demonstrated a U-shaped pattern, wherein the average infarct proportion was minimized at 515 degree-minutes (AUC34) of cooling, and increased thereafter. In a single case of direct brain tissue oxygen monitoring during selective hypothermia, brain tissue oxygen strongly correlated with brain temperature reduction over the course of selective hypothermia to 23°C. Conclusions: In a large animal model of selective hypothermia applied to focal ischemia, there is a non-monotone relationship between duration and depth of hypothermia and stroke volume reduction. This suggests a limit to depth or duration of selective hypothermia for optimal neuroprotection. Further research is required to delineate more precise depth and duration limits for selective hypothermia.

Mobile Stroke Unit Operational Metrics: Institutional Experience, Systematic Review and Meta-Analysis.

Background: The available literature on mobile stroke units (MSU) has focused on clinical outcomes, rather than operational performance. Our objective was to establish normalized metrics and to conduct a meta-analysis of the current literature on MSU performance. Methods: Our MSU in upstate New York serves 741,000 people. We present prospectively collected, retrospectively analyzed data from the inception of our MSU in October of 2018, through March of 2021. Rates of transportation/dispatch and MSU utilization were reported. We also performed a meta-analysis using MEDLINE, SCOPUS, and Cochrane Library databases, calculating rates of tPA/dispatch, tPA-per-24-operational-hours ("per day"), mechanical thrombectomy (MT)/dispatch and MT/day. Results: Our MSU was dispatched 1,719 times in 606 days (8.5 dispatches/24-operational-hours) and transported 324 patients (18.8%) to the hospital. Intravenous tPA was administered in 64 patients (3.7% of dispatches) and the rate of tPA/day was 0.317 (95% CI 0.150-0.567). MT was performed in 24 patients (1.4% of dispatches) for a MT/day rate of 0.119 (95% CI 0.074-0.163). The MSU was in use for 38,742 minutes out of 290,760 total available minutes (13.3% utilization rate). Our meta-analysis included 14 articles. Eight studies were included in the analysis of tPA/dispatch (342/5,862) for a rate of 7.2% (95% CI 4.8-9.5%, I2 = 92%) and 11 were included in the analysis of tPA/day (1,858/4,961) for a rate of 0.358 (95% CI 0.215-0.502, I2 = 99%). Seven studies were included for MT/dispatch (102/5,335) for a rate of 2.0% (95% CI 1.2-2.8%, I2 = 67%) and MT/day (103/1,249) for a rate of 0.092 (95% CI 0.046-0.138, I2 = 91%). Conclusions: In this single institution retrospective study and meta-analysis, we outline the following operational metrics: tPA/dispatch, tPA/day, MT/dispatch, MT/day, and utilization rate. These metrics are useful for internal and external comparison for institutions with or considering developing mobile stroke programs.

Endovascular Therapy is Effective for Large Vessel Occlusion Despite Concurrent Cancer.

OBJECTIVES: Ischemic stroke and concurrent cancer is increasingly recognized. However, optimal management is uncertain. As mechanical thrombectomy has become the standard of care for large vessel occlusion, more patients with cancer are presenting for embolectomy. However, it is unknown whether this subgroup has the same benefit profile described in multiple randomized trials for thrombectomy for large vessel occlusion. Our objective was to retrospectively evaluate a North American embolectomy database for safety and outcomes in patients with active cancer. MATERIALS AND METHODS: A case series of 284 embolectomies over 30 months at a single North American stroke center were divided into thrombectomy patients with active cancer(n=25) and those without active cancer (n=259). We compared patient characteristics, procedural characteristics, and procedural outcomes between patients with and without active cancer. Univariate and multivariate analysis of angiographic outcomes, postoperative hemorrhage, and functional outcome was performed. RESULTS: Of the 284 thrombectomy cases, 9% were performed on patients with active cancer. Active cancer patients had a similar recanalization grade and post-operative hemorrhage rate, compared to patients without cancer. Active cancer patients had a significantly higher 90 day mortality (40% vs 20%, p=0.018). On multivariate analysis, good functional outcome (mRS 0-2) was not impacted by active cancer. However, when mRS was evaluated as an ordinal shift analysis, worse functional outcome was associated with active cancer (OR 2.98; 95% CI, 1.29 to 6.59), greater age, NIHSS> 10, and ASPECTS<9. CONCLUSIONS: This single center retrospective series of active cancer patients undergoing thrombectomy for large vessel occlusion demonstrates similar rates of recanalization, post-operative hemorrhage, and good outcomes. While the active cancer group has a high short-term mortality, the potential to maintain quality of life in the survivors makes thrombectomy reasonable in this patient population. Awareness of ischemic stroke as a complication of cancer and the safety of thrombectomy in this population are important as this population subtype is expected to grow with improved oncology and stroke care.

Mobile stroke care expedites intravenous thrombolysis and endovascular thrombectomy.

BACKGROUND: The number of mobile stroke programmes has increased with evidence, showing they expedite intravenous thrombolysis. Outstanding questions include whether time savings extend to patients eligible for endovascular therapy and impact clinical outcomes. OBJECTIVE: Our mobile stroke unit (MSU), based at an academic medical centre in upstate New York, launched in October 2018. We reviewed prospective observational data sets over 26 months to identify MSU and non-MSU emergency medical service (EMS) patients who underwent intravenous thrombolysis or endovascular thrombectomy for comparison of angiographic and clinical outcomes. RESULTS: Over 568 days in service, the MSU was dispatched 1489 times (2.6/day) and transported 300 patients (20% of dispatches). Intravenous tissue plasminogen activator (tPA) was administered to 57 MSU patients and the average time from 911 call-to-tPA was 42.5 min (±9.2), while EMS transported 73 patients who received tPA at 99.4 min (±35.7) (p<0.001). Seven MSU patients (12%) received tPA from 3.5 hours to 4.5 hours since last known well and would likely have been outside the window with EMS care. Endovascular thrombectomy was performed on 21 MSU patients with an average 911 call-to-groin puncture time of 99.9 min (±18.1), while EMS transported 54 patients who underwent endovascular thrombectomy (ET) at 133.0 min (±37.0) (p=0.0002). There was no difference between MSU and traditional EMS in modified Rankin score at 90-day clinic follow-up for patients undergoing intravenous thrombolysis or endovascular thrombectomy, whether assessed as a dichotomous or ordinal variable. CONCLUSIONS: Mobile stroke care expedited both intravenous thrombolysis and endovascular thrombectomy. There is an ongoing need to show improved functional outcomes with MSU care.

Complications of transradial versus transfemoral access for neuroendovascular procedures: a meta-analysis.

BACKGROUND: Transradial access (TRA) has gained increased usage among neurointerventionalists. However, the overall safety profile of access site complications (ASCs) and non-access site complications (NASCs) of TRA versus transfemoral access (TFA) for neuroendovascular procedures remains unclear. METHODS: A systematic literature review and meta-analysis using a random effects model was conducted to investigate the pooled odds ratios (OR) of ASCs and NASCs. Randomized, case-control, and cohort studies comparing access-related complications were analyzed. An assessment of study heterogeneity and publication bias was also completed. RESULTS: Seventeen comparative studies met the inclusion criteria for final analysis. Overall, there was a composite ASC rate of 1.8% (49/2767) versus 3.2% (168/5222) for TRA and TFA, respectively (P<0.001). TRA was associated with a lower odds of ASC compared with TFA (OR 0.42; 95% CI 0.25 to 0.68, P<0.001, I2=31%). There was significantly lower odds of complications within the intervention and diagnostic subgroups. For NASC, TRA had a lower composite incidence of complications than TFA at 1.2% (31/2586) versus 4.2% (207/4909), P<0.001). However, on meta-analysis, we found no significant difference overall between TRA and TFA for NASCs (OR 0.79; 95% CI 0.51 to 1.22, P=0.28, I2=0%), which was also the case on subgroup analysis. CONCLUSION: On meta-analysis, the current literature indicates that TRA is associated with a lower incidence of ASCs compared with TFA, but is not associated with a lower rate of NASCs.

Noncurative microsurgery for cerebral aneurysms: a systematic review and meta-analysis of wrapping, residual, and recurrence rates.

OBJECTIVE: Microsurgery for cerebral aneurysms is called definitive, yet some patients undergo a craniotomy that results in noncurative treatment. Furthermore, the overall rate of noncurative microsurgery for cerebral aneurysms is unclear. The objective of this study was to complete a systematic review and meta-analysis to quantify three scenarios of noncurative treatment: aneurysm wrapping, postclipping remnants, and late regrowth of completely obliterated aneurysms. METHODS: A PRISMA-guided systematic literature review of the MEDLINE and Cochrane Library databases and meta-analysis was completed. Studies were included that detailed rates of aneurysm wrapping, residua confirmed with imaging, and regrowth after confirmed total occlusion. Pooled rates were subsequently calculated using a random-effects model. An assessment of statistical heterogeneity and publication bias among the included studies was also completed for each analysis, with resultant I2 values and p values determined with Egger's test. RESULTS: Sixty-four studies met the inclusion criteria for final analysis. In 41 studies, 573/15,715 aneurysms were wrapped, for a rate of 3.5% (95% CI 2.7%-4.2%, I2 = 88%). In 43 studies, 906/13,902 aneurysms had residual neck or dome filling, for a rate of 6.4% (95% CI 5.2%-7.6%, I2 = 93%). In 15 studies, 71/2568 originally fully occluded aneurysms showed regrowth, for a rate of 2.1% (95% CI 1.2%-3.1%, I2 = 58%). Together, there was a total rate of noncurative surgery of 12.0% (95% CI 11.5%-12.5%). Egger's test suggested no significant publication bias among the studies. Meta-regression analysis revealed that the reported rate of aneurysm wrapping has significantly declined over time, whereas the rates of aneurysm residua and recurrence have not significantly changed. CONCLUSIONS: Open microsurgery for cerebral aneurysm results in noncurative treatment approximately 12% of the time. This metric may be used to counsel patients and as a benchmark for other treatment modalities. This investigation is limited by the high degree of heterogeneity among the included studies.

Endovascular selective hypothermia facilitates giant aneurysm clipping: illustrative case.

BACKGROUND: The authors present a case of selective hypothermia used for neuroprotection during clipping of a giant partially thrombosed middle cerebral artery (MCA) aneurysm. Although these cases have traditionally required deep hypothermic cardiac arrest, this case illustrates a novel and entirely endovascular solution that avoids cardiac standstill and whole-body cooling. OBSERVATIONS: This is, to the authors' knowledge, the first case in human surgery of a catheter-based selective hypothermic circuit used to facilitate MCA trapping for almost 30 minutes. Core temperatures never dropped below 34°C, and the patient recovered uneventfully and has been well for over 5 years. LESSONS: The technical nuances and physiological changes unique to selective hypothermia are discussed.