Endovascular Treatment for Complex Vascular Pathologies in the Pediatric Population: Experience from a Center with Dual-Trained Neurosurgeons.

OBJECTIVE: Endovascular treatment of complex vascular pathologies in the pediatric population is often performed by non-pediatric subspecialists with adaptation of equipment and techniques developed for adult patients. We aimed to report our center's experience with safety and outcomes of endovascular treatments for pediatric vascular pathologies. METHODS: We performed a retrospective review of our endovascular database. All patients ≤18 years who underwent endovascular treatment between January 1, 2004 and December 1, 2022 were included. RESULTS: During the study time frame, 118 cerebral angiograms were performed for interventional purposes in 55 patients. Of these patients, 8(14.5%) had intracranial aneurysms, 21(38.2%) had intracranial arteriovenous malformations (AVMs), 6(10.9%) had tumors, 5(9.1%) had arterial occlusions (n=3) or dissections (n=2), 8(14.5%) had vein of Galen malformations, and 7(12.7%) had other cerebrovascular conditions. Of the total 118 procedures, access-site complications occurred in 2(1.7%), intraprocedural complications occurred in 3(2.5%), and transient neurological deficits were observed after 2(1.7%). Treatment-related mortality occurred in 1(1.8%) patient. CONCLUSIONS: Neurointervention in pediatric patients was safe and effective in our experience.

Femoral versus radial access for middle meningeal artery embolization for chronic subdural hematomas: multicenter propensity score matched study.

BACKGROUND: With transradial access (TRA) being more progressively used in neuroendovascular procedures, we compared TRA with transfemoral access (TFA) in middle meningeal artery embolization (MMAE) for chronic subdural hematoma (cSDH). METHODS: Consecutive patients undergoing MMAE for cSDH at 14 North American centers (2018-23) were included. TRA and TFA groups were compared using propensity score matching (PSM) controlling for: age, sex, concurrent surgery, previous surgery, hematoma thickness and side, midline shift, and pretreatment antithrombotics. The primary outcome was access site and overall complications, and procedure duration; secondary endpoints were surgical rescue, radiographic improvement, and technical success and length of stay. RESULTS: 872 patients (median age 73 years, 72.9% men) underwent 1070 MMAE procedures (54% TFA vs 46% TRA). Access site hematoma occurred in three TFA cases (0.5%; none required operative intervention) versus 0% in TRA (P=0.23), and radial-to-femoral conversion occurred in 1% of TRA cases. TRA was more used in right sided cSDH (58.4% vs 44.8%; P<0.001). Particle embolics were significantly higher in TFA while Onyx was higher in TRA (P<0.001). Following PSM, 150 matched pairs were generated. Particles were more utilized in the TFA group (53% vs 29.7%) and Onyx was more utilized in the TRA group (56.1% vs 31.5%) (P=0.001). Procedural duration was longer in the TRA group (median 68.5 min (IQR 43.1-95) vs 59 (42-84); P=0.038), and radiographic success was higher in the TFA group (87.3% vs 77.4%; P=0.036). No differences were noted in surgical rescue (8.4% vs 10.1%, P=0.35) or technical failures (2.4% vs 2%; P=0.67) between TFA and TRA. Sensitivity analysis in the standalone MMAE retained all associations but differences in procedural duration. CONCLUSIONS: In this study, TRA offered comparable outcomes to TFA in MMAE for cSDH in terms of access related and overall complications, technical feasibility, and functional outcomes. Procedural duration was slightly longer in the TRA group, and radiographic success was higher in the TFA group, with no differences in surgical rescue rates.

Radiomics-Based Predictive Nomogram for Assessing the Risk of Intracranial Aneurysms.

Aneurysm wall enhancement (AWE) has the potential to be used as an imaging biomarker for the risk stratification of intracranial aneurysms (IAs). Radiomics provides a refined approach to quantify and further characterize AWE's textural features. This study examines the performance of AWE quantification combined with clinical information in detecting symptomatic IAs. Ninety patients harboring 104 IAs (29 symptomatic and 75 asymptomatic) underwent high-resolution magnetic resonance imaging (HR-MRI). The assessment of AWE was performed using two different methods: 3D-AWE mapping and composite radiomics-based score (RadScore). The dataset was split into training and testing subsets. The testing set was used to build two different nomograms using each modality of AWE assessment combined with patients' clinical information and aneurysm morphological data. Finally, each nomogram was evaluated on an independent testing set. A total of 22 radiomic features were significantly different between symptomatic and asymptomatic IAs. The 3D-AWE mapping nomogram achieved an area under the curve (AUC) of 0.77 (63% accuracy, 78% sensitivity, and 58% specificity). The RadScore nomogram exhibited a better performance, achieving an AUC of 0.83 (77% accuracy, 89% sensitivity, and 73% specificity). The comprehensive analysis of IAs with the quantification of AWE data through radiomic analysis, patient clinical information, and morphological aneurysm metrics achieves a high accuracy in detecting symptomatic IA status.

An International, Multicenter Feasibility Study on Active and Continuous Irrigation With Cerebrospinal Fluid Exchange for Improving Outcomes in Cerebral Ventriculitis.

BACKGROUND AND OBJECTIVES: Cerebral ventriculitis remains a challenging neurosurgical condition because of poor outcomes including mortality rates of nearly 80% and a prolonged course of treatment in survivors. Despite current conventional management, outcomes in some cases remain unsatisfactory, with no definitive therapeutic guidelines. This feasibility study aims to explore the use of a novel active, continuous irrigation and drainage system (IRRAflow [IRRAS AB]) combined with intraventricular drug delivery for patients with cerebral ventriculitis. METHODS: We conducted a multicenter, international, retrospective study of patients with ventriculitis who were treated with use of the IRRAflow system. Data collected included patient demographics, comorbidities, admission Glasgow Coma Scale score, baseline modified Rankin Scale (mRS) score, and imaging findings. Catheter occlusions, infections, and shunt placement were recorded for outcome assessment, along with discharge mRS scores and in-hospital deaths. RESULTS: Four centers contributed data for a total of 21 patients who had IRRAflow placement for treatment of ventriculitis. Thirteen (61.9%) were men (mean age = 49.8 ± 14.87 years). The median baseline mRS score was 1. The median Glasgow Coma Scale score at admission was 13. The etiology of ventriculitis was iatrogenic in 12 (57.1%) patients and secondary to an abscess in 9 (42.9%). No cases reported hemorrhage or failure of IRRAflow placement. Antibiotics were administered through the IRRAflow system in 13 (61.9%) cases in addition to systemic dosing. Sixteen (76.2%) patients had significant clinical improvement and resolution of ventriculitis. Seven (33.3%) patients required shunt placement after resolution because of persistent hydrocephalus. There were 6 (28.6%) in-hospital deaths. CONCLUSION: The use of active irrigation with drainage for continuous delivery of intraventricular irrigation fluid with antibiotics led to dramatically low mortality. In our case series, it led to a marked improvement in neurological status, imaging findings, and cerebrospinal fluid profiles, making it a technically feasible and safe treatment for ventriculitis.

Hybrid Clot Histomic-Transcriptomic Models Predict Functional Outcome After Mechanical Thrombectomy in Acute Ischemic Stroke.

BACKGROUND AND OBJECTIVES: Histologic and transcriptomic analyses of retrieved stroke clots have identified features associated with patient outcomes. Previous studies have demonstrated the predictive capacity of histology or expression features in isolation. Few studies, however, have investigated how paired histologic image features and expression patterns from the retrieved clots can improve understanding of clot pathobiology and our ability to predict long-term prognosis. We hypothesized that computational models trained using clot histomics and mRNA expression can predict early neurological improvement (ENI) and 90-day functional outcome (modified Rankin Scale Score, mRS) better than models developed using histological composition or expression data alone. METHODS: We performed paired histological and transcriptomic analysis of 32 stroke clots. ENI was defined as a delta-National Institutes of Health Stroke Score/Scale > 4, and a good long-term outcome was defined as mRS ≤2 at 90 days after procedure. Clots were H&E-stained and whole-slide imaged at 40×. An established digital pathology pipeline was used to extract 237 histomic features and to compute clot percent composition (%Comp). When dichotomized by either the ENI or mRS thresholds, differentially expressed genes were identified as those with absolute fold-change >1.5 and q < 0.05. Machine learning with recursive feature elimination (RFE) was used to select clot features and evaluate computational models for outcome prognostication. RESULTS: For ENI, RFE identified 9 optimal histologic and transcriptomic features for the hybrid model, which achieved an accuracy of 90.8% (area under the curve [AUC] = 0.98 ± 0.08) in testing and outperformed models based on histomics (AUC = 0.94 ± 0.09), transcriptomics (AUC = 0.86 ± 0.16), or %Comp (AUC = 0.70 ± 0.15) alone. For mRS, RFE identified 7 optimal histomic and transcriptomic features for the hybrid model. This model achieved an accuracy of 93.7% (AUC = 0.94 ± 0.09) in testing, also outperforming models based on histomics (AUC = 0.90 ± 0.11), transcriptomics (AUC = 0.55 ± 0.27), or %Comp (AUC = 0.58 ± 0.16) alone. CONCLUSION: Hybrid models offer improved outcome prognostication for patients with stroke. Identified digital histology and mRNA signatures warrant further investigation as biomarkers of patient functional outcome after thrombectomy.

Under Pressure: Emotional Reactions to Stress of Neurosurgeons and Neurosurgical Trainees.

OBJECTIVE: Neurosurgeons demonstrate some of the highest levels of burnout among surgeons, yet little research has been done to understand the underlying stressors that neurosurgeons and trainees experience and the emotional responses to them. Our goal was to conduct a feasibility study identifying job stressors and emotional responses among neurosurgeons rather than generalize findings across the profession. METHODS: Emphasizing a qualitative approach in this feasibility and descriptive study, we strategically selected a small sample of neurosurgical attendings, residents, and fellows at 2 United States academic neurosurgical departments to ensure an in-depth analysis laying the groundwork for future extensive research. Participants were asked to complete a questionnaire regarding work-related stressors and high- and low-arousal emotional responses to these stressors, as well as a standardized Depression, Anxiety, and Stress Scale. Both quantitative and qualitative analyses evaluating types of stressors and emotional responses reported were assessed based on participant training level. RESULTS: Participants identified 3 main stressors: 1) administrative deficiencies; 2) delivering bad news/saving lives; and 3) work-life balance. A low frequency of negative emotional responses was reported, but those reported were mainly high-arousal emotions. Limited prior training in coping strategies was also reported. We also found that residents, fellows, and faculty surgeons reported about work stressors and coping strategies differently. CONCLUSIONS: The results of our study provide an understanding of neurosurgical professionals' unique emotional landscape, emphasizing the need for reforms in administrative practices, enhanced, healthy coping strategies, and career stage-specific mental health support.

Comparison between Woven EndoBridge and coiling with and without stent assistance for intracranial bifurcation and wide-neck aneurysms: a comprehensive systematic review and meta-analysis.

OBJECTIVE: The recent introduction of the Woven EndoBridge (WEB) has presented an alternative treatment modality for intracranial bifurcation and wide-neck aneurysms with a growing body of literature evaluating its efficacy. However, no previous systematic review has focused on comparing WEB with previously using endovascular approaches, specifically primary coiling (PC) and stent-assisted coiling (SAC). Herein, the authors present the first systematic review summarizing available literature to reach a consensus regarding the safety and effectiveness of WEB. METHODS: A systematic review of articles identified through a search of PubMed, Embase, Scopus, and Web of Science was conducted. Studies were included if they compared WEB with PC or SAC from any aspect for intracranial aneurysms. Risk of bias was assessed using the Risk of Bias in Non-Randomized Studies-of Interventions tool. Meta-analyses of the outcomes based on stent use and rupture status were performed. RESULTS: A total of 16 studies were included. The three endovascular approaches were comparable in terms of baseline characteristics except for older age and smaller aneurysm neck in the PC group (p < 0.05). Moreover, the follow-up duration was shorter in the WEB group (p < 0.05). Although the WEB group demonstrated lower complete and adequate immediate occlusion rates (p < 0.01), the rates at follow-up evaluations were comparable with SAC and PC (p = 0.61 and p = 0.27, respectively). The WEB group experienced significantly fewer unfavorable neurological outcomes than the SAC group (p = 0.04), while comparable to the PC group (p = 0.36). Retreatment rates were comparable between WEB and coiling (p = 0.92). The WEB group had fewer hemorrhagic and thromboembolic complications (p < 0.01 and p = 0.01, respectively), with similar neurological and procedure-related complications compared with combined PC and SAC groups. Lastly, mortality was comparable among the different endovascular approaches. CONCLUSIONS: This study provides evidence on the noninferiority of WEB compared with PC and SAC in terms of angiographic outcomes. Meanwhile, our findings on lower complication rates, cost, and improved operative aspects associated with WEB establish this novel endovascular treatment as a safe and effective alternative for the treatment of bifurcation and wide-neck aneurysms.

Decoding Molecular Mechanisms Underlying Outcomes After Ischemic Stroke Thrombectomy by RNA Sequencing of Retrieved Clots.

BACKGROUND: Transcriptomic profiling has emerged as a powerful tool for exploring the molecular landscape of ischemic stroke clots and providing insights into the pathophysiological mechanisms underlying stroke progression and recovery. In this study, we aimed to investigate the relationship between stroke clot transcriptomes and stroke thrombectomy outcome, as measured by early neurological improvement (ENI) 30 (i.e., a 30% reduction in NIHSS at 24 h post-thrombectomy). HYPOTHESIS: We hypothesized that there exist distinct clot gene expression patterns between good and poor neurological outcomes. METHODS: Transcriptomic analysis of 32 stroke clots retrieved by mechanical thrombectomy was conducted. Transcriptome data of these clots were analyzed to identify differentially expressed genes (DEGs), defined as those with a log(fold-change) ≥ 1.5 and q < 0.05 between samples with good and poor early neurological outcomes. Gene ontology and bioinformatics analyses were performed on genes with p < 0.01 to identify enriched biological processes and Ingenuity Pathway Analysis canonical pathways. Moreover, AUC analysis assessed the predictive power of DEGs for 90-day function outcome (mRS ≤ 2) and cellular composition of clot was predicted using CIBERSORT. We also assessed whether differential enrichment of immune cell types could indicate patient survival. RESULTS: A total of 41 DEGs were identified. Bioinformatics showed that enriched biological processes and pathways emphasized the chronic immune response and matrix metalloproteinase inhibition. Moreover, 25 of the DEGs were found to be significant predictors of 90-day mRS. These genes were indicative of monocytes enrichment and neutrophil depletion in patients with poorer outcomes. CONCLUSION: Our study revealed a distinct gene expression pattern and dysregulated biological pathways associated with ENI. This expression pattern was also predictive of long-term outcome, suggesting a biological link between those ENIs and 90-day mRS.

Global Disparities in the Presentation and Management of Aneurysmal Subarachnoid Hemorrhage: A Review and Analysis.

OBJECTIVE: Aneurysmal subarachnoid hemorrhage (aSAH) is associated with high mortality rates. There is a significant gap in the literature describing global disparities in demographics, management, and outcomes among patients with aSAH. We aimed to conduct a systematic review and meta-analysis to assess global disparities in aSAH presentation and management. METHODS: PubMed and Embase databases were queried from earliest records to November 2022 for aSAH literature. Presentation, demographics, comorbidities, treatment methods, and outcomes data were collected. Articles that did not report aSAH-specific patient management and outcomes were excluded. Pooled weighted prevalence rates were calculated. Random effects model rates were reported. RESULTS: After screening, 33 articles representing 10,553 patients were included. The prevalence of Fisher grade 3 or 4 aSAH in high- and lower-income countries (HIC and LIC), respectively, was 79.8% (P < 0.01) and 84.1 (P < 0.01). Prevalence of male aSAH patients in HIC and LIC, respectively, was 35.8% (P < 0.01) and 45.0% (P < 0.01). Prevalence of treatment in aSAH patients was 99.5% (P < 0.01) and 99.4% (P = 0.16) in HIC and LIC, respectively. In HIC, 35% (P < 0.01) of aneurysms in aSAH patients were treated with coiling. No LIC reported coiling for aSAH treatment; LIC only reported rates of surgical clipping, with a total prevalence of 92.4% (P < 0.01) versus 65.6% (P < 0.01) in HIC. CONCLUSION: In this analysis, we found similar rates of high-grade SAH hemorrhages in HIC and LIC but a lack of endovascular coil embolization treatments reported in LIC. Additional research and discussion are needed to identify reasons for treatment disparities and intervenable societal factors to improve aSAH outcomes worldwide.

Radiomics-Based Predictive Nomogram for Assessing the Risk of Intracranial Aneurysms.

Background: Aneurysm wall enhancement (AWE) has the potential to be used as an imaging biomarker for the risk stratification of intracranial aneurysms (IAs). Radiomics provides a refined approach to quantify and further characterize AWE's textural features. This study examines the performance of AWE quantification combined with clinical information in detecting symptomatic IAs. Methods: Ninety patients harboring 104 IAs (29 symptomatic and 75 asymptomatic) underwent high-resolution magnetic resonance imaging (HR-MRI). The assessment of AWE was performed using two different methods: 3D-AWE mapping and composite radiomics-based score (RadScore). The dataset was split into training and testing subsets. The testing set was used to build two different nomograms using each modality of AWE assessment combined with patients' demographic information and aneurysm morphological data. Finally, each nomogram was evaluated on an independent testing set. Results: A total of 22 radiomic features were significantly different between symptomatic and asymptomatic IAs. The 3D-AWE Mapping nomogram achieved an area under the curve (AUC) of 0.77 (63% accuracy, 78% sensitivity and 58% specificity). The RadScore nomogram exhibited a better performance, achieving an AUC of 0.83 (77% accuracy, 89% sensitivity and 73% specificity). Conclusions: Combining AWE quantification through radiomic analysis with patient demographic data in a clinical nomogram achieved high accuracy in detecting symptomatic IAs.

The Influence of Coagulopathy on Radiographic and Clinical Outcomes in Patients Undergoing Middle Meningeal Artery Embolization as Standalone Treatment for Non-acute Subdural Hematomas.

Middle meningeal artery embolization (MMAE) is emerging as a safe and effective standalone intervention for non-acute subdural hematomas (NASHs); however, the risk of hematoma recurrence after MMAE in coagulopathic patients is unclear. To characterize the impact of coagulopathy on treatment outcomes, we analyzed a multi-institutional database of patients who underwent standalone MMAE as treatment for NASH. We classified 537 patients who underwent MMAE as a standalone intervention between 2019 and 2023 by coagulopathy status. Coagulopathy was defined as use of anticoagulation/antiplatelet agents or pre-operative thrombocytopenia (platelets <100,000/µL). Demographics, pre-procedural characteristics, in-hospital course, and patient outcomes were collected. Thrombocytopenia, aspirin use, antiplatelet agent use, and anticoagulant use were assessed using univariate and multivariate analyses to identify any characteristics associated with the need for rescue surgical intervention, mortality, adverse events, and modified Rankin Scale score at 90-day follow-up. Propensity score-matched cohorts by coagulopathy status with matching covariates adjusting for risk factors implicated in surgical recurrence were evaluated by univariate and multivariate analyses. Minimal differences in pre-operative characteristics between patients with and those without coagulopathy were observed. On unmatched and matched analyses, patients with coagulopathy had higher rates of requiring subsequent surgery than those without (unmatched: 9.9% vs. 4.3%; matched: 12.6% vs. 4.6%; both p < 0.05). On matched multivariable analysis, patients with coagulopathy had an increased odds ratio (OR) of requiring surgical rescue (OR 3.95; 95% confidence interval [CI] 1.68-9.30; p < 0.01). Antiplatelet agent use (ticagrelor, prasugrel, or clopidogrel) was also predictive of surgical rescue (OR 4.38; 95% CI 1.51-12.72; p = 0.01), and patients with thrombocytopenia had significantly increased odds of in-hospital mortality (OR 5.16; 95% CI 2.38-11.20; p < 0.01). There were no differences in follow-up radiographic and other clinical outcomes in patients with and those without coagulopathy. Patients with coagulopathy undergoing standalone MMAE for treatment of NASH may have greater risk of requiring surgical rescue (particularly in patients using antiplatelet agents), and in-hospital mortality (in thrombocytopenic patients).

Supraclavicular Artery Island Flap for Treatment of Cervical Wound Defects and Persistent Cerebrospinal Fluid Leaks: A Technical Note and Systematic Review of the Literature.

BACKGROUND: Soft tissue defects and persistent cerebrospinal fluid (CSF) leaks can create complications after cervical spinal surgery. The supraclavicular artery island (SAI) flap is useful in closing tissue defects, particularly in these complex surgeries and multiple reinterventions. However, technical reports in this context are scarce. We describe application of the SAI flap technique to control persistent CSF leak in the first documented instance (to our knowledge) of a low-grade fibromyxoid sarcoma (LGFMS) in the cervical epidural space. Additionally, we conducted a comprehensive review of PubMed, Embase, and Google Scholar from their earliest records through December 17, 2023 using combined terms, "supraclavicular artery island flap AND spine" and "supraclavicular AND flap AND spine". TECHNICAL NOTE: A 56-year-old woman with arm pain and weakness presented with a cervical epidural mass extending from C4-C6 and associated spinal cord compression. She underwent a 3-level corpectomy and tumor resection. Primary dural closure was impossible due to the dural invasion, and reintervention with an SAI flap and definitive lumboperitoneal shunting were required to control and seal the CSF leak. SYSTEMATIC LITERATURE REVIEW: Seven case reports describing SAI flap for spinal surgery complications were identified. The indications in those cases were correcting esophageal and hypopharyngeal perforations after cervical fusion and discectomy and persistent soft tissue coverage after cervical instrumentation. CONCLUSIONS: The SAI flap technique provided wound defect coverage in this case and is suitable for addressing issues such as persistent CSF leaks or soft tissue coverage after cervical spine surgery.

Transcarotid Arterial Revascularization of Symptomatic Internal Carotid Artery Disease: A Systematic Review and Study-Level Meta-Analysis.

BACKGROUND: Transcarotid artery revascularization (TCAR) is an interventional therapy for symptomatic internal carotid artery disease. Currently, the utilization of TCAR is contentious due to limited evidence. In this study, we evaluate the safety and efficacy of TCAR in patients with symptomatic internal carotid artery disease compared with carotid endarterectomy (CEA) and carotid artery stenting (CAS). METHODS: A systematic review was conducted, spanning from January 2000 to February 2023, encompassing studies that used TCAR for the treatment of symptomatic internal carotid artery disease. The primary outcomes included a 30-day stroke or transient ischemic attack, myocardial infarction, and mortality. Secondary outcomes comprised cranial nerve injury and major bleeding. Pooled odds ratios (ORs) for each outcome were calculated to compare TCAR with CEA and CAS. Furthermore, subgroup analyses were performed based on age and degree of stenosis. In addition, a sensitivity analysis was conducted by excluding the vascular quality initiative registry population. RESULTS: A total of 7 studies involving 24 246 patients were analyzed. Within this patient cohort, 4771 individuals underwent TCAR, 12 350 underwent CEA, and 7125 patients underwent CAS. Compared with CAS, TCAR was associated with a similar rate of stroke or transient ischemic attack (OR, 0.77 [95% CI, 0.33-1.82]) and myocardial infarction (OR, 1.29 [95% CI, 0.83-2.01]) but lower mortality (OR, 0.42 [95% CI, 0.22-0.81]). Compared with CEA, TCAR was associated with a higher rate of stroke or transient ischemic attack (OR, 1.26 [95% CI, 1.03-1.54]) but similar rates of myocardial infarction (OR, 0.9 [95% CI, 0.64-1.38]) and mortality (OR, 1.35 [95% CI, 0.87-2.10]). CONCLUSIONS: Although CEA has traditionally been considered superior to stenting for symptomatic carotid stenosis, TCAR may have some advantages over CAS. Prospective randomized trials comparing the 3 modalities are needed.

General Versus Nongeneral Anesthesia for Middle Meningeal Artery Embolization for Chronic Subdural Hematomas: Multicenter Propensity Score Matched Study.

BACKGROUND AND OBJECTIVES: The choice of anesthesia type (general anesthesia [GA] vs nongeneral anesthesia [non-GA]) in middle meningeal artery embolization (MMAE) procedures for chronic subdural hematomas (cSDH) differs between institutions and left to care team discretion given lack of standard guidelines. We compare the outcomes of GA vs non-GA in MMAE. METHODS: Consecutive patients receiving MMAE for cSDH at 14 North American centers (2018-2023) were included. Clinical, cSDH characteristics, and technical/clinical outcomes were compared between the GA/non-GA groups. Using propensity score matching (PSM), patients were matched controlling for age, baseline modified Rankin Scale, concurrent/prior surgery, hematoma thickness/midline shift, and baseline antiplatelet/anticoagulation. The primary end points included surgical rescue and radiographic success rates (≥50% reduction in maximum hematoma thickness with minimum 2 weeks of imaging). Secondary end points included technical feasibility, procedural complications, and functional outcomes. RESULTS: Seven hundred seventy-eight patients (median age 73 years, 73.2% male patients) underwent 956 MMAE procedures, 667 (70.4%) were non-GA and 280 were GA (29.6%). After running 1:3 PSM algorithm, this resulted in 153 and 296 in the GA and non-GA groups, respectively. There were no baseline/procedural differences between the groups except radial access more significantly used in the non-GA group (P = .001). There was no difference between the groups in procedural technical feasibility, complications rate, length of stay, surgical rescue rates, or favorable functional outcome at the last follow-up. Subsequent 1:1 sensitivity PSM retained the same results. Bilateral MMAE procedures were more performed under non-GA group (75.8% vs 67.2%; P = .01); no differences were noted in clinical/radiographic outcomes between bilateral vs unilateral MMAE, except for longer procedure duration in the bilateral group (median 73 minutes [IQR 48.3-100] vs 54 minutes [39-75]; P < .0001). Another PSM analysis comparing GA vs non-GA in patients undergoing stand-alone MMAE retained similar associations. CONCLUSION: We found no significant differences in radiological improvement/clinical outcomes between GA and non-GA for MMAE.

Transvenous embolization of noncavernous dural arteriovenous fistulas (dAVFs): A systematic review and meta-analysis.

BACKGROUND: Intracranial dural arteriovenous fistulas (dAVFs) are abnormal connections between arteries and veins within the dura mater. Various treatment modalities, such as surgical ligation, endovascular intervention, and radiosurgery, aim to close the fistulous connection. Although transvenous embolization (TVE) is the preferred method for carotid-cavernous fistulas, its description and outcomes for noncavernous dAVFs vary. This has prompted a systematic review and meta-analysis to comprehensively assess the effectiveness of TVE in treating noncavernous dAVFs, addressing variations in outcomes and techniques. METHODS: We searched PubMed and Embase, spanning from the earliest records to December 2022, to identify pertinent English-language articles detailing the utilization of TVE. We focused on specific procedural details, outcomes, and complications in patients older than 18 years. The data collected and analyzed comprised the sample size, number of fistulas, publication specifics, presenting symptoms, fistula grades, and pooled rates of embolizations, outcomes, follow-up information, and complications. RESULTS: From a total of 565 screened articles, 15 retrospective articles encompassing 166 patients spanning across seven countries met the inclusion criteria. Their Newcastle-Ottawa scores ranged from 6 to 8. Intraprocedural complication rate was 10% (95% confidence interval [CI] = 5.9-17.1) and in-hospital postprocedural complication rate was 5.4% (95% CI = 2.8-10.6). Prevalence of in-hospital mortality was 5.5% (95% CI = 2.9-10.6). Complication rate during follow-up was 8.6% (95% CI = 4.7-15.7) with fistula rupture occurring in 5.5% (95% CI = 2.6-11.6) of patients. Complete obliteration rate at final angiographic follow-up was 94.9% (95% CI = 90.3-99.9). Symptoms improved in 95% (95% CI = 89.8-100) of patients at final follow-up. CONCLUSION: To our knowledge, we present the first meta-analysis assessing obliteration rates, outcomes, and complications of TVE for dAVFs. Our analysis highlights the higher (>90%) complete obliteration rates. Large prospective multicenter studies are needed to better define the utility of TVE for noncavernous dAVFs.

A novel swine model of selective middle meningeal artery catheterization and embolization.

BACKGROUND: Middle meningeal artery (MMA) embolization is a promising intervention as a stand-alone or adjunct treatment to surgery in patients with chronic subdural hematomas. There are currently no large animal models for selective access and embolization of the MMA for preclinical evaluation of this endovascular modality. Our objective was to introduce a novel in vivo model of selective MMA embolization in swine. METHODS: Diagnostic cerebral angiography with selective microcatheter catheterization into the MMA was performed under general anesthesia in five swine. Anatomical variants in arterial meningeal supply were examined. In two animals, subsequent embolization of the MMA with a liquid embolic agent (Onyx-18) was performed, followed by brain tissue harvest and histological analysis. RESULTS: The MMA was consistently localized as a branch of the internal maxillary artery just distal to the origin of the ascending pharyngeal artery. Additional meningeal supply was observed from the external ophthalmic artery, although not present consistently. MMA embolization with Onyx was technically successful and feasible. Histological analysis showed Onyx material within the MMA lumen. CONCLUSIONS: Microcatheter access into the MMA in swine with liquid embolic agent delivery represents a reproducible model of MMA embolization. Anatomical variations in the distribution of arterial supply to the meninges exist. This model has a potential application for comparing therapeutic effects of various embolic agents in a preclinical setting that closely resembles the MMA embolization procedure in humans.

MicroCT and Histological Analysis of Clot Composition in Acute Ischemic Stroke : A Comparative Study of MT-Retrieved Clots and Clot Analogs.

PURPOSE: Assessing clot composition on prethrombectomy computed tomography (CT) imaging may help in stroke treatment planning. In this study we seek to use microCT imaging of fabricated blood clots to understand the relationship between CT radiographic signals and the biological makeup. METHODS: Clots (n = 10) retrieved by mechanical thrombectomy (MT) were collected, and 6 clot analogs of varying RBC composition were made. We performed paired microCT and histological image analysis of all 16 clots using a ScanCo microCT 100 (4.9 µm resolution) and standard H&E staining (imaged at 40×). From these data types, first order statistic (FOS) radiomics were computed from microCT, and percent composition of RBCs (%RBC) was computed from histology. Polynomial and linear regression (LR) were used to build statistical models based on retrieved thrombus microCT and %RBC that were evaluated for their ability to predict the %RBC of clot analogs from mean HU. Correlation analyses of microCT FOS with composition were completed for both retrieved clots and analogs. RESULTS: The LR model fits relating MT-retrieved clot %RBC with mean (R2 = 0.625, p = 0.006) and standard deviation (R2 = 0.564, p < 0.05) in HUs on microCT were significant. Similarly, LR models relating analog histological %RBC to analog protocol %RBC (R2 = 0.915, p = 0.003) and mean HUs on microCT (R2 = 0.872, p = 0.007) were also significant. When the LR model built using MT-retrieved clots was used to predict analog %RBC from mean HUs, significant correlation was observed between predictions and actual histological %RBC (R2 = 0.852, p = 0.009). For retrieved clots, significant correlations were observed for energy and total energy with %RBC and %FP (|R| > 0.7, q < 0.01). Analogs further demonstrated significant correlation between FOS energy, total energy, variance and %WBC (|R| > 0.9, q < 0.01). CONCLUSION: MicroCT can be used to build models that predict AIS clot composition from routine CT parameters and help us to better understand radiomic signatures associated with clot composition and first pass outcomes. In future work, such observations can be used to better infer clot composition and inform thrombectomy prognostics from pretreatment CTs.

Preradiosurgical Embolization of Arteriovenous Malformations Reduces Target Volume - The Main Determinant for Complete Obliteration.

BACKGROUND: Embolization and stereotactic radiosurgery (SRS) have increasingly been used to treat complex arteriovenous malformations (AVMs). We studied outcomes of AVM patients treated through a multidisciplinary approach, examined the effect of embolization on SRS success, and analyzed predictors of treatment failure. METHODS: We retrospectively reviewed a prospectively maintained database of patients with AVMs treated with Gamma Knife (Leksell) SRS over an 11-year period. Patients with incomplete medical records and follow-up <2 years were excluded. Demographics, clinical presentation, previous rupture history, angiographic nidus size, Spetzler-Martin (S-M) grade, adjunctive endovascular embolization and microsurgical resection, radiologic evidence of obliteration and hemorrhage, and clinical outcomes (modified Rankin Scale [mRS] scores) were recorded. Radiosurgery-related details including nidus volume and number of sessions and radiosurgery-, embolization-, and resection-associated complications were also recorded. RESULTS: Eighty-three patients (mean age, 41.0 ± 21.3 years) were included. Mean reduction in AVM nidus target volume with endovascular embolization was 66.0 ± 19.7%. S-M grade reduction was achieved in 51.6% cases. Total obliteration after SRS was achieved in 56 AVMs (67.5%) after 2 years, and in 38 (86.4%) after 4 years. Two (2.4%) patients had rehemorrhage after SRS. Overall complication rate was 3.6%. Median angiographic follow-up was 55.5 months. Favorable outcomes (mRS = 0-2) were seen in 77.1%. SRS target volume was an independent predictor of treatment failure regardless of pre-SRS embolization. CONCLUSIONS: High AVM obliteration rates were achieved with judicious use of radiosurgery alone or with embolization. Embolization reduced target nidus volume by an average of 66%. SRS target volume was an independent predictor of treatment failure.