Direct Versus Indirect Revascularization for Moyamoya: a Large Multicenter Study.

BACKGROUND: Moyamoya is a chronic occlusive cerebrovascular disease of unknown etiology causing neovascularization of the lenticulostriate collaterals at the base of the brain. Although revascularization surgery is the most effective treatment for moyamoya, there is still no consensus on the best surgical treatment modality as different studies provide different outcomes. OBJECTIVE: In this large case series, we compare the outcomes of direct (DR) and indirect revascularisation (IR) and compare our results to the literature in order to reflect on the best revascularization modality for moyamoya. METHODS: We conducted a multicenter retrospective study in accordance with the Strengthening the Reporting of Observational studies in Epidemiology guidelines of moyamoya affected hemispheres treated with DR and IR surgeries across 13 academic institutions predominantly in North America. All patients who underwent surgical revascularization of their moyamoya-affected hemispheres were included in the study. The primary outcome of the study was the rate of symptomatic strokes. RESULTS: The rates of symptomatic strokes across 515 disease-affected hemispheres were comparable between the two cohorts (11.6% in the DR cohort vs 9.6% in the IR cohort, OR 1.238 (95% CI 0.651 to 2.354), p=0.514). The rate of total perioperative strokes was slightly higher in the DR cohort (6.1% for DR vs 2.0% for IR, OR 3.129 (95% CI 0.991 to 9.875), p=0.052). The rate of total follow-up strokes was slightly higher in the IR cohort (8.1% vs 6.6%, OR 0.799 (95% CI 0.374 to 1.709) p=0.563). CONCLUSION: Since both modalities showed comparable rates of overall total strokes, both modalities of revascularization can be performed depending on the patient's risk assessment.

Balloon-mounting stent versus balloon angioplasty for intracranial arterial stenosis: A systematic review and meta-analysis.

BACKGROUND: Intracranial artery atherosclerotic stenosis (ICAS) is a major cause of stroke, especially in Asian countries. Current treatment options, including balloon-mounted stent (BMS) and balloon angioplasty (BA), lack sufficient evidence to determine a preferred approach. This systematic review and meta-analysis aimed to compare the efficacy and safety of BMS and BA in treating ICAS. METHODS: Following PRISMA 2020 guidelines, we conducted a comprehensive search in PubMed, Web of Science, and Scopus up to December 1, 2023. Eligible studies compared BMS with BA in patients diagnosed with ICAS. Primary outcomes included the success rate and occurrence of stroke (ischemic or hemorrhagic). Secondary outcomes were perforator occlusion, in-stent thrombosis, death, and restenosis. Statistical analysis was conducted using R software version 4.3.1, employing a random-effects model. RESULTS: Five high-quality studies involving 707 patients (515 males, 192 females) were included. BMS had a significantly higher success rate compared to BA (Risk Ratio [RR]: 1.13; CI: 1.03 to 1.24, p < 0.01; I2 = 14 %). The overall risk for stroke (ischemic and hemorrhagic) was significantly higher in BMS (RR: 2.97; CI: 1.32 to 6.67, p < 0.01; I2 = 0 %). However, no significant difference was found between BMS and BA regarding ischemic stroke (RR: 2.33; CI: 0.80 to 6.74, p = 0.12; I2 = 0 %). Additionally, no significant differences were observed in terms of perforator occlusion, in-stent thrombosis, dissection, minor and major strokes, and mortality rates. BMS was associated with a lower risk of restenosis (RR: 0.31; 95 % CI: 0.12 to 0.83, p = 0.02; I2 = 0 %). CONCLUSION: Our results indicate that BMS might be associated with higher success and lower restenosis rates than BA in the treatment of ICAS but with an increased overall risk of stroke. No significant differences were observed in ischemic stroke, perforator occlusion, in-stent thrombosis, dissection, minor and major strokes, and mortality rates. The choice of treatment should consider these findings, alongside the technical challenges and desired angiographic outcomes. Future randomized controlled trials are necessary to further elucidate these results.

Comparative outcomes of middle meningeal artery embolization with statins versus embolization alone in the treatment of chronic subdural hematoma: a systematic review and meta-analysis.

Chronic subdural hematoma (cSDH) is common among the elderly, with surgical evacuation as a prevalent treatment, facing recurrence rates up to 30%. Recently, middle meningeal artery embolization (MMAE) has emerged as a promising approach, offering reduced treatment failures and recurrence rates. Additionally, statins, known for their anti-inflammatory properties, have been considered as a potential adjunctive or sole treatment for cSDH. However, the combination of MMAE with statins remains understudied. This systematic review and meta-analysis aims to evaluate the comparative outcomes of MMAE with statins versus MMAE alone in the treatment of cSDH. A comprehensive systematic search of the PubMed, Web of Science, and SCOPUS databases was conducted. Inclusion criteria were: studies published in English between the dates of inception of each database and August 2023, studies comparing the treatment of cSDH with either MMAE + statin or MMAE alone were included. Main outcome measures were complete resolution of the hematoma at follow-up and the recurrence rates. Two studies comprising 715 patients were included; 408 patients underwent MMAE + statin; and 307 underwent MMAE alone. MMAE + statin was not significantly superior to MMAE alone in achieving complete resolution of the hematoma at follow-up (RR: 0.99; CI: 0.91 to 1.07, P = 0.84), nor was it a significant difference in rates of recurrence (RR: 1.35; CI: 0.83 to 2.17, P = 0.21) between the two groups. MMAE + statin did not demonstrate significant superiority over MMAE alone for achieving complete resolution and decreasing the recurrence rates in cSDH patients. Further research with larger, randomized studies may be required to fully elucidate the potential synergistic effects of MMAE and statins in this patient population.

Comprehensive morphomechanical analysis of brain aneurysms.

OBJECTIVE: Brain aneurysms comprise different compartments that undergo unique biological processes. A detailed multimodal analysis incorporating 3D aneurysm wall enhancement (AWE), computational fluid dynamics (CFD), and finite element analysis (FEA) data can provide insights into the aneurysm wall biology. METHODS: Unruptured aneurysms were prospectively imaged with 7 T high-resolution MRI (HR-MRI). 3D AWE color maps of the entire aneurysm wall were generated and co-registered with contour plots of morphomechanical parameters derived from CFD and FEA. A multimodal analysis of the entire aneurysm was performed using 3D circumferential AWE (3D-CAWE), wall tension (WT), time-averaged wall shear stress (TAWSS), wall shear stress gradient (WSSG), and oscillatory shear index (OSI). A detailed compartmental analysis of each aneurysm's dome, bleb, and neck was also performed. RESULTS: Twenty-six aneurysms were analyzed. 3D-CAWE + aneurysms had higher WT (p = 0.03) and higher TAWSS (p = 0.045) than 3D-CAWE- aneurysms. WT, TAWSS, and WSSG were lower in areas of focal AWE in the aneurysm dome compared to the neck (p = 0.009, p = 0.049, and p = 0.040, respectively), whereas OSI was higher in areas of focal AWE compared to the neck (p = 0.020). When compared to areas of no AWE of the aneurysm sac (AWE = 0.92 vs. 0.49, p = 0.001), blebs exhibited lower WT (1.6 vs. 2.45, p = 0.010), lower TAWSS (2.6 vs. 6.34), lower OSI (0.0007 vs. 0.0010), and lower WSSG (2900 vs. 5306). Fusiform aneurysms had a higher 3D-CAWE and WT than saccular aneurysms (p = 0.046 and p = 0.003, respectively). CONCLUSIONS: Areas of focal high AWE in the sac and blebs are associated with low wall tension, low wall shear stress, and low flow conditions (TAWSS and WSSG). Conversely, the neck had average AWE, high wall tension, high wall shear stress, and high flow conditions. The aneurysm dome and the aneurysm neck have different morphomechanical environments, with increased mechanical load at the neck.

Predictors of aneurysm occlusion following treatment with the WEB device: systematic review and case series.

The Woven EndoBridge (WEB) device is becoming increasingly popular for treatment of wide-neck aneurysms. As experience with this device grows, it is important to identify factors associated with occlusion following WEB treatment to guide decision making and screen patients at high risk for recurrence. The aim of this study was to identify factors associated with adequate aneurysm occlusion following WEB device treatment in the neurosurgical literature and in our case series. A systematic review of the present literature was conducted to identify studies related to the prediction of WEB device occlusion. In addition, a retrospective review of our institutional data for patients treated with the WEB device was performed. Demographics, aneurysm characteristics, procedural variables, and 6-month follow-up angiographic outcomes were recorded. Seven articles totaling 450 patients with 456 aneurysms fit our criteria. Factors in the literature associated with inadequate occlusion included larger size, increased neck width, partial intrasaccular thrombosis, irregular shape, and tobacco use. Our retrospective review identified 43 patients with 45 aneurysms. A total of 91.1% of our patients achieved adequate occlusion at a mean follow-up time of 7.32 months. Increasing degree of contrast stasis after WEB placement on the post-deployment angiogram was significantly associated with adequate occlusion on follow-up angiogram (p = 0.005) and with Raymond-Roy classification (p = 0.048), but not with retreatment (p = 0.617). In our systematic review and case series totaling 450 patients with 456 aneurysms, contrast stasis on post-deployment angiogram was identified as a predictor of adequate aneurysm occlusion, while morphological characteristics such as larger size and wide neck negatively impact occlusion.

Phase 1/2a Trial of ISPASM.

BACKGROUND AND PURPOSE: Microthrombosis could play a role in delayed cerebral ischemia after aneurysmal subarachnoid hemorrhage. Tirofiban has shown promising results in reducing delayed cerebral ischemia in retrospective studies. However, the safety of using tirofiban in aneurysmal subarachnoid hemorrhage is not rigorously established. METHODS: A phase 1/2a double-blinded randomized controlled trial (2:1 randomization) to assess the safety of a 7-day intravenous infusion of tirofiban compared with placebo, in patients with aneurysmal subarachnoid hemorrhage treated with ventriculostomy placed in the operative room and coiling was conducted. The primary end point was any intracranial hemorrhage during the hospital stay. The secondary end points were: incidence of radiographic and clinical vasospasm, incidence of delayed cerebral ischemia, and incidence of cerebral ischemic changes noted on magnetic resonance imaging or computed tomography. RESULTS: Eighteen patients received intravenous tirofiban and 12 received placebo. There was no difference in baseline characteristics except for higher male proportions in the tirofiban group. There was no difference in death, in development of new or change in existing intracranial hemorrhages, in thrombocytopenia, and need for shunts in the two arms. However, the tirofiban arm had a lower incidence of delayed cerebral ischemia compared with placebo (6% [1/18] versus 33% [4/12]; P=0.04), and less radiographic vasospasm as detected by catheter angiogram or computed tomography angiography (P=0.01) and computed tomography perfusion (P=0.01). CONCLUSIONS: The above preliminary results support proceeding with further testing of the safety and efficacy of 7-day intravenous infusion of tirofiban in a pragmatic (placing external ventricular drain by the bedside), multicenter setting, and using a larger population. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT03691727.

Impact of Intracerebral Hematoma Evacuation During Decompressive Hemicraniectomy on Functional Outcomes.

BACKGROUND AND PURPOSE: Decompressive hemicraniectomy has been used to treat spontaneous intracerebral hemorrhage, but the benefit of evacuating the hematoma during the procedure is unclear. We aim to evaluate the utility of performing clot evacuation during hemicraniectomy for spontaneous intracerebral hemorrhage. METHODS: Retrospective cohort of consecutive patients (2010-2019) treated with decompressive hemicraniectomy for a spontaneous supratentorial intracerebral hemorrhage at the University of Iowa. We compared hemicraniectomy alone to hemicraniectomy plus hematoma evacuation. We analyzed clinical features and hematoma characteristics. The outcomes at 6 months were dichotomized into unfavorable (Glasgow Outcome Scale score 1-3) and favorable (Glasgow Outcome Scale score 4-5). RESULTS: Eighty-three patients underwent decompressive hemicraniectomy for spontaneous intracerebral hemorrhage, 52 with hematoma evacuation, and 31 without hematoma evacuation. There were no statistically significant differences in clinical and radiographic characteristics between the 2 groups. Evacuating the hematoma in addition to hemicraniectomy did not change the odds of favorable outcome at 6 months (P=0.806). CONCLUSIONS: In this retrospective study, the performance of hematoma evacuation during decompressive hemicraniectomy for spontaneous intracerebral hemorrhage may not change functional outcomes over performing the hemicraniectomy alone.

Concentration of Lp(a) (Lipoprotein[a]) in Aneurysm Sac Is Associated With Wall Enhancement of Unruptured Intracranial Aneurysm.

BACKGROUND AND PURPOSE: Atherosclerotic remodeling of the aneurysm wall, which could be detected as aneurysm wall enhancement (AWE) by magnetic resonance-vessel wall imaging, is a part of degenerative change of unruptured intracranial aneurysms (UIAs). The purpose of this study was to determine whether the luminal concentrations of atherosclerotic proteins in the aneurysm sac were associated with increased wall enhancement of UIAs in vessel wall imaging. METHODS: We performed a prospective study of subjects undergoing endovascular treatments for UIAs. All subjects underwent evaluation using 3T-magnetic resonance imaging, including pre/postcontrast vessel wall imaging of the UIAs. Blood samples were collected from the aneurysm sac and the parent artery during endovascular procedures. Presence/absence of AWE was correlated with the delta difference in concentration for each atherosclerotic protein between the lumen of UIA and in the parent artery. RESULTS: A total of consecutive 17 patients with 19 UIAs were enrolled. The delta difference of lipoprotein(a) was significantly higher in UIAs with AWE compared with those without AWE (-6.9±16.0 versus -45.4±44.9 µg/mL, P=0.03). CONCLUSIONS: Higher luminal concentrations of lipoprotein(a) in the aneurysm sac were significantly associated with increased wall enhancement of UIAs. A larger study is needed to confirm these findings.

A comparative study of transradial versus transfemoral approach for flow diversion.

PURPOSE: Data in neurointerventional literature is extremely limited regarding the safety and efficacy of flow diversion using transradial access (TRA). We aim to demonstrate the safety and efficacy of intracranial aneurysm treatment with the Pipeline Embolization Device (PED) using TRA compared to transfemoral access (TFA). METHODS: We conducted a retrospective analysis of a prospectively maintained database and identified 79 consecutive patients who underwent neuroendovascular embolization for cerebral aneurysms using the PED from April 2018 through October 2019. Patients were divided into 2 groups: TRA (32 patients) and TFA (47 patients). A comparative analysis was performed between the two groups. RESULTS: There was no significant difference in postoperative intracranial hemorrhage (p>.99), symptomatic ischemic stroke (p=.512), access site complications (p=.268), or other complications (p=.512). However, there was a significant increase in overall complications (14.9% vs. 0.0%, p=.038) and procedure duration (71.4 min ± 31.2 vs. 58.5 ± 20.3, p=.018) in the TFA group. There was no significant difference in complete occlusion at latest follow-up (19/25, 76.0% vs. 35/40, 87.5%; p=.311), 6-month follow-up (17/23, 73.9% vs. 33/38, 86.8%; p=.303), or 12-month follow-up (8/8, 100.0% vs. 5/6, 83.3%; p=.429). There was also no significant difference in rate of retreatment (p>.99), morbidity (p=.512), mortality (p>.99), latest follow-up (p=.985), or loss of follow-up (p=.298). CONCLUSIONS: The feasibility and efficacy of flow diversion with the PED via TRA for the treatment of intracranial aneurysms is comparable to TFA. Widespread adoption of this approach may be facilitated by improvements in device navigation and manipulation via radial-specific engineering.

Detection and Quantification of Symptomatic Atherosclerotic Plaques With High-Resolution Imaging in Cryptogenic Stroke.

BACKGROUND AND PURPOSE: High-resolution vessel wall imaging (HR-VWI) is a powerful tool in diagnosing intracranial vasculopathies not detected on routine imaging. We hypothesized that 7T HR-VWI may detect the presence of atherosclerotic plaques in patients with intracranial atherosclerosis disease initially misdiagnosed as cryptogenic strokes. METHODS: Patients diagnosed as cryptogenic stroke but suspected of having an intracranial arteriopathy by routine imaging were prospectively imaged with HR-VWI. If intracranial atherosclerotic plaques were identified, they were classified as culprit or nonculprit based on the likelihood of causing the index stroke. Plaque characteristics, such as contrast enhancement, degree of stenosis, and morphology, were analyzed. Contrast enhancement was determined objectively after normalization with the pituitary stalk. A cutoff value for plaque-to-pituitary stalk contrast enhancement ratio (CR) was determined for optimal prediction of the presence of a culprit plaque. A revised stroke cause was adjudicated based on clinical and HR-VWI findings. RESULTS: A total of 344 cryptogenic strokes were analyzed, and 38 eligible patients were imaged with 7T HR-VWI. Intracranial atherosclerosis disease was adjudicated as the final stroke cause in 25 patients. A total of 153 intracranial plaques in 374 arterial segments were identified. Culprit plaques (n=36) had higher CR and had concentric morphology when compared with nonculprit plaques (P≤0.001). CR ≥53 had 78% sensitivity for detecting culprit plaques and a 90% negative predictive value. CR ≥53 (P=0.008), stenosis ≥50% (P<0.001), and concentric morphology (P=0.030) were independent predictors of culprit plaques. CONCLUSIONS: 7T HR-VWI allows identification of underlying intracranial atherosclerosis disease in a subset of stroke patients with suspected underlying vasculopathy but otherwise classified as cryptogenic. Plaque analysis in this population demonstrated that culprit plaques had more contrast enhancement (CR ≥53), caused a higher degree of stenosis, and had a concentric morphology.

Differential Risk Factors and Outcomes of Ischemic Stroke due to Cervical Artery Dissection in Young Adults.

INTRODUCTION: Cervical artery dissection (CeAD) is a major cause of ischemic stroke in young adults. Our understanding of the specific risk factors and clinical course of CeAD is still evolving. In this study, we evaluated the differential risk factors and outcomes of CeAD-related strokes among young adults. METHODS: The study population consisted of young patients 15-45 years of age consecutively admitted with acute ischemic stroke to our comprehensive stroke center between January 1, 2010, and November 30, 2016. Diagnosis of CeAD was based on clinical and radiological findings. Univariate and multivariable logistic regression analyses were used to assess the risk factors and clinical outcomes associated with CeAD-related strokes. RESULTS: Of the total 333 patients with acute ischemic stroke included in the study (mean ± SD age: 36.4 ± 7.1 years; women 50.8%), CeAD was identified in 79 (23.7%) patients. As compared to stroke due to other etiologies, patients with CeAD were younger in age, more likely to have history of migraine and recent neck manipulation and were less likely to have hypertension, diabetes, and previous history of stroke. Clinical outcomes of CeAD were comparable to strokes due to other etiologies. Within the CeAD group, higher initial stroke severity and history of tobacco use were associated with higher modified Rankin Scale score at follow-up. CONCLUSIONS: While history of migraine and neck manipulation are significantly associated with CeAD, most of the traditional vascular risk factors for stroke are less prevalent in this group when compared to strokes due to other etiologies. For CeAD-related strokes, higher initial stroke severity and history of tobacco use may be associated with higher stroke-related disability, but overall, patients with CeAD have similar outcomes as compared to strokes due to other etiologies.

In-House Anesthesia and Interventional Radiology Technologist Support Optimize Mechanical Thrombectomy Workflow after Hours.

BACKGROUND AND PURPOSE: Prior literature suggests after-hours delay leads to poor functional outcomes in stroke patients undergoing thrombectomy. We aimed to evaluate the impact of time of presentation on mechanical thrombectomy (MT) metrics and its association with long-term functional outcome in an Interventional Radiology (IR) suite equipped operating room (OR) setting. METHODS: Retrospective review of prospectively maintained database on all stroke patients undergoing mechanical thrombectomy between January 2015 and December 2018 at our CSC. Work hours were defined by official OR work hours (Monday-Friday 7 AM and 5 PM) and after-hours as between 5 PM and 7 AM during weekdays and weekends as well as official hospital holidays. Primary outcome was 90-day modified Rankin Scale (mRS). Secondary outcomes included door to groin puncture time and procedural complications. RESULTS: A total of 315 patients were included in the analyses. 209 (66.4%) received mechanical thrombectomy after hours and 106 (33.6%) during work hours. There was no difference in the shift distribution of functional outcome on the mRS at 90 days (OR: 1.14, CI: 0.72-1.78, p=0.58) and the percentage of patients achieving functional independence (mRS 0-2) at 90 days (43.1% vs. 41.3%; p=0.83) between the after hour and work hour groups respectively. Similarly, there was no difference in median door to groin times and procedural complications among both groups, with significant year on year improvement in overall time metrics. CONCLUSIONS: Our study showed that undergoing MT during off-hours had similar functional outcomes when compared to MT during working hours in an OR setting. The after-hours deleterious effect might disappear when MT is performed in a system with 24-hours in-house Anesthesia and IR tech services.

Cigarette Smoke Initiates Oxidative Stress-Induced Cellular Phenotypic Modulation Leading to Cerebral Aneurysm Pathogenesis.

OBJECTIVE: Cigarette smoke exposure (CSE) is a risk factor for cerebral aneurysm (CA) formation, but the molecular mechanisms are unclear. Although CSE is known to contribute to excess reactive oxygen species generation, the role of oxidative stress on vascular smooth muscle cell (VSMC) phenotypic modulation and pathogenesis of CAs is unknown. The goal of this study was to investigate whether CSE activates a NOX (NADPH oxidase)-dependent pathway leading to VSMC phenotypic modulation and CA formation and rupture. APPROACH AND RESULTS: In cultured cerebral VSMCs, CSE increased expression of NOX1 and reactive oxygen species which preceded upregulation of proinflammatory/matrix remodeling genes (MCP-1, MMPs [matrix metalloproteinase], TNF-α, IL-1ß, NF-κB, KLF4 [Kruppel-like factor 4]) and downregulation of contractile genes (SM-α-actin [smooth muscle α actin], SM-22α [smooth muscle 22α], SM-MHC [smooth muscle myosin heavy chain]) and myocardin. Inhibition of reactive oxygen species production and knockdown of NOX1 with siRNA or antisense decreased CSE-induced upregulation of NOX1 and inflammatory genes and downregulation of VSMC contractile genes and myocardin. p47phox-/- NOX knockout mice, or pretreatment with the NOX inhibitor, apocynin, significantly decreased CA formation and rupture compared with controls. NOX1 protein and mRNA expression were similar in p47phox-/- mice and those pretreated with apocynin but were elevated in unruptured and ruptured CAs. CSE increased CA formation and rupture, which was diminished with apocynin pretreatment. Similarly, NOX1 protein and mRNA and reactive oxygen species were elevated by CSE, and in unruptured and ruptured CAs. CONCLUSIONS: CSE initiates oxidative stress-induced phenotypic modulation of VSMCs and CA formation and rupture. These molecular changes implicate oxidative stress in the pathogenesis of CAs and may provide a potential target for future therapeutic strategies.

Definition and Prioritization of Data Elements for Cohort Studies and Clinical Trials on Patients with Unruptured Intracranial Aneurysms: Proposal of a Multidisciplinary Research Group.

INTRODUCTION: Variability in usage and definition of data characteristics in previous cohort studies on unruptured intracranial aneurysms (UIA) complicated pooling and proper interpretation of these data. The aim of the National Institute of Health/National Institute of Neurological Disorders and Stroke UIA and Subarachnoid Hemorrhage (SAH) Common Data Elements (CDE) Project was to provide a common structure for data collection in future research on UIA and SAH. METHODS: This paper describes the development and summarization of the recommendations of the working groups (WGs) on UIAs, which consisted of an international and multidisciplinary panel of cerebrovascular specialists on research and treatment of UIAs. Consensus recommendations were developed by review of previously published CDEs for other neurological diseases and the literature on UIAs. Recommendations for CDEs were classified by priority into 'Core,' 'Supplemental-Highly Recommended,' 'Supplemental,' and 'Exploratory.' RESULTS: Ninety-one CDEs were compiled; 69 were newly created and 22 were existing CDEs. The CDEs were assigned to eight subcategories and were classified as Core (8), Supplemental-Highly Recommended (23), Supplemental (25), and Exploratory (35) elements. Additionally, the WG developed and agreed on a classification for aneurysm morphology. CONCLUSION: The proposed CDEs have been distilled from a broad pool of characteristics, measures, or outcomes. The usage of these CDEs will facilitate pooling of data from cohort studies or clinical trials on patients with UIAs.

Computed Tomography Angiogram Derived From Computed Tomography Perfusion Done with Low Iodine Volume Protocol Preserves Diagnostic Yield for Middle Cerebral Artery-M2 Occlusions.

BACKGROUND: Computed tomography angiogram (CTA) derived from computed tomography perfusion (CTP) has been proposed to avoid addition of separate CT perfusion protocol for selection of large vessel occlusion in acute stroke patients. Previous studies have validated this technique for proximal large vessel occlusions. In this study, we test reliability for identifying M2 occlusions on CTA derived from CTP. METHODS: Through a retrospective search of the institutional thrombectomy database, we identified 28 cases with M2-MCA occlusion, of which 24 met the inclusion criteria for analysis. An additional 20 cases without M2-MCA occlusion (either normal or M1-MCA occlusion) were randomly mixed in the database to reduce observer bias. The baseline images of the CTP study in these 48 cases were then independently analyzed by 3 readers with varying level of expertise. The digital subtraction angiography (DSA) images were also independently reviewed where available. The percentage of agreement among reviewers as well as the probability of agreement of the reviewers, when compared to the DSA findings was also calculated. RESULTS: The observed agreement for the image quality amongst the 3 readers (n = 48) varied between 0.78 and 0.95 and tended to be higher for the M1 segment MCA and lower for distal M2-MCA. The observed agreements comparing 3 image reviewers versus DSA in M2 patients (n = 24) was 98% for identifying occlusion (95% CI 95%-100%), 94% for identifying proximal M2 occlusion (95% CI 88%-98%), and 91% (95% CI 84%-97%) and 90% (95% CI 83%-95%), respectively for correctly identifying inferior and superior branch of M2 occlusion. CONCLUSION: CTA data derived from CT Perfusion study preserves diagnostic yield for correctly identifying M2 occlusion.

Angiographic Features of Intracranial Aneurysms in Ecuador.

BACKGROUND: Most of the literature describing morphological features of intracranial aneurysms (IAs) is from North-America, East-Asia, and Europe. There is limited data from South-America. We describe the epidemiologic and angiographic features of ruptured and unruptured IAs in a cohort of patients from Ecuador. METHODS: We conducted a retrospective analysis of prospectively acquired databases from 3 different tertiary hospitals over a 3-year period (2014-2017). In a per-patient basis, odd ratios (ORs) of ruptured presentation for each variable using a univariate logistic regression model were calculated. An aneurysm-based multivariate analysis was performed to calculate rupture ORs for each variable. RESULTS: Our sample included 557 patients with 761 IAs. Mean patient age was 52.2 years (range 18-82). Sixty-eight percent were women, and almost 90% presented with ruptured aneurysms and concomitant subarachnoid hemorrhage (SAH). Mean size of all the IAs was 6.4 mm ± 3.98 mm. Most IAs were located in anterior circulation (96.6%): 28.4% medial cerebral artery, 24.4% anterior cerebral artery or anterior communicating artery (ACOM), and 23.5% posterior communicating artery (PCOM). Only 6 basilar tip aneurysms (0.8%) were reported. In the adjusted analysis, aneurysms located in the ACOM (OR 1.89, 95% CI 1.29-2.78) and PCOM (OR 1.84, 95% CI 1.25-2.71), size larger than 5 mm (OR 2.84, 95% CI 2.04-3.93) and 7 mm (OR 2.28, 95% CI 1.64-3.19), and those with non-saccular morphology (OR 9.87, 95% CI 2.21-44.14) were significantly associated with ruptured presentation. CONCLUSIONS: The prevalence of posterior circulation IAs in Ecuador, particularly basilar tip aneurysms, is low when compared to previous reports from developed countries. In our sample, IAs greater than 5 mm (and ≥7 mm) in size, ACOM and PCOM locations, and IAs with nonsaccular morphologies (blister and fusiform) were significantly associated with SAH presentation.

Absence of Collaterals is Associated with Larger Infarct Volume and Worse Outcome in Patients with Large Vessel Occlusion and Mild Symptoms.

BACKGROUND: Mechanical thrombectomy is the standard of care for patients with large vessel occlusion (LVO) presenting with severe symptoms; however, little is known about the best treatment for patients with LVO and mild symptoms. The absence of good collaterals has been associated with a worse outcome in patients with LVO. In this study, we aim to assess the use of collateral score to identify patients with LVO and mild symptoms that might benefit from mechanical thrombectomy (MT). METHODS: A retrospective review of prospectively collected data on patients presenting with mild ischemic stroke (National Institute of Health Stroke Scale [NIHSS] <6) and anterior circulation LVO between September 2015 and July 2017 was performed. Collected data included baseline demographics, NIHSS on admission, Alberta Stroke Program Early CT Score (ASPECTS), location of occlusion, collateral score using Tan scoring system, final infarct volume, and 90-day modified Rankin Scale (mRS). Patients who underwent MT were excluded from this analysis. Two multivariable models were used to assess outcomes. A gamma distributed generalized linear regression model with a log link was used to examine the impact on final infarct volume. To predict the odds of a positive 90-day outcome we estimated a logistic regression. RESULTS: Forty-one patients were identified. Mean age was 67.7-years with 56.1% males. Median NIHSS on admission was 3. The most common vessels involved were the middle cerebral artery (26), internal carotid artery (14), and anterior cerebral artery (1). Twelve patients received intravenous alteplase. Median ASPECTS score was 9, median collateral score was 2.3. Median infarct volume was 10.7 mL. A good functional outcome (mRS 0-2) at 90 days was achieved in 86.4% of patients. There was a negative relationship between collateral score and final infarct volume (-.3134, P = .046). Multivariable regression results showed that with a one-point increase in NIHSS on admission there was a 25% increase in final infarct volume. Higher infarct volume was associated with lower odds of achieving good functional outcome (mRS 0-2) (odds ratio .96, P = .049 [95% confidence interval .918-.999). CONCLUSIONS: Most patients with anterior circulation LVO and low NIHSS achieve good long-term functional outcome, however, approximately 15% had significant disability. The absence of collaterals correlates with a larger final infarct volume and a worse long-term functional outcome. Collateral score might be a useful tool in identifying patients with LVO and low NIHSS who might benefit from MT.

Secular Increases in Spontaneous Subarachnoid Hemorrhage during Pregnancy: A Nationwide Sample Analysis.

IMPORTANCE: Understanding of the epidemiology, outcomes, and management of spontaneous subarachnoid hemorrhage (sSAH) during pregnancy is limited. Small, single center series suggest a slight increase in morbidity and mortality. OBJECTIVE: To determine if incidence of sSAH in pregnancy is increasing nationally and also to study the outcomes for this patient population. DESIGN, SETTING, AND PARTICIPANTS: A retrospective analysis was performed utilizing the Nationwide Inpatient Sample (NIS) and Healthcare Cost and Utilization Project for the years 2002-2014 for sSAH hospitalizations. The NIS is a large administrative database designed to produce nationally weighted estimates. Female patients age 15-49 with sSAH were identified using the International Classification of Diseases, 9th Revision, Clinical Modification code 430. Pregnancy and maternal diagnosis were identified using pregnancy related ICD codes validated by previous studies. The Cochran-Armitage trend test and parametric tests were utilized to analyze temporal trends and group comparisons. Main Outcomes and Measures: National trend for incidence of sSAH in pregnancy, age, and race/ethnicity as well as associated risk factors and outcomes. RESULTS: During the time period, there were 73,692 admissions for sSAH in women age 15-49 years, of which 3978 (5.4%) occurred during pregnancy. The proportion of sSAH during pregnancy hospitalizations increased from 4.16 % to 6.33% (P-Trend < .001) during the 12 years of the study. African-American women (8.19%) and Hispanic (7.11%) had higher rates of sSAH during pregnancy than whites (3.83%). In the NIS data, the incidence of sSAH increased from 5.4/100,000 deliveries (2002) to 8.5/100,000 deliveries (2014; P-Trend < .0001). The greatest increase in sSAH was noted to be among pregnant African-American women from (13.4 [2002]) to (16.39 [2014]/100,000 births). Mortality was lower in pregnant women (7.69% versus 17.37%, P < .0001). Pregnant women had a higher likelihood of being discharged to home (69.78% versus 53.66%, P < .0001) and lower likelihood of discharge to long term facility (22.4% versus 28.7%, P < .0001) than nonpregnant women after sSAH hospitalization. CONCLUSIONS AND RELEVANCE: There is an upward trend in the incidence of sSAH occurring during pregnancy. There was disproportionate increase in incidence of sSAH in the African American and younger mothers. Outcomes were better for both pregnant and nonpregnant women treated at teaching hospitals and in pregnant women in general as compared to nonpregnant women.

Disparities in Inter-hospital Helicopter Transportation for Hispanics by Geographic Region: A Threat to Fairness in the Era of Thrombectomy.

BACKGROUND AND PURPOSE: Mechanical thrombectomy (MT) is a time-dependent therapy that is only available at a limited number of hospitals. As such, patients that live at a considerable distance of those specialized centers often require rapid interhospital emergent evacuation with Helicopter Emergency Medical Services (HEMS) to be considered for MT. It is not known whether the use of HEMS is equitable across different groups of patients. METHODS: Acute ischemic stroke patients emergently transferred to another facility were identified in a retrospective review of a large Medicare claims database. Mode of transportation (HEMS, advanced, or basic ground ambulances) was determined by CPT codes. Distance from patient's residence to the closest center with MT capabilities was calculated. Generalized linear mixed logit models were used to determine the odds of HEMS relative to ground services for Hispanic and non-Hispanic black (NHB) patients relative to non-Hispanic white (NHW) patients while controlling for confounders. RESULTS: A total of 8027 patients that underwent emergent interhospital transportation were analyzed. HEMS utilization was 18.1% for NHB, 20.6% for Hispanics, and 21.6% for NHW (P = .054). In adjusted analyses for confounders, including distance to a MT-capable hospital, Hispanic patients were less likely than NHWs to be transported by HEMS. While that association had marginal significance for the whole United States (OR = .76; 95% CI, .57-1.01; P = .055), it was statistically significant for patients living in the southern region of the United States (OR = .6; 95% CI, .40-.92; P = .019). DISCUSSION: Our findings suggest there is a disparity in the use of HEMS in Hispanic stroke patients compared to NHW. Such a disparity may delay arrival to a MT-capable hospital, delay treatment times, or lead to ineligibility for MT altogether. Given the known benefit of MT and known existing disparities in stroke treatment and outcomes, it is important to further investigate and address disparities in mode of interhospital transportation.