Intracranial artery calcification: Frequency, determinants, and modification of outcomes from endovascular thrombectomy.

INTRODUCTION: Intracranial artery calcification (ICAC) is a common finding on computed tomography (CT) in patients presenting with large vessel occlusion acute ischemic stroke (LVO-AIS) and could serve as a useful biomarker of intracranial atherosclerosis and altered intracranial vessel pliability in patients undergoing endovascular thrombectomy (EVT). METHODS: This was a retrospective cohort study analyzing consecutive patients undergoing CT head prior to EVT between 2016 and 2020. Extent of ICAC proximal to the target vessel was scored using a validated grading scale examining thickness and circumferential extent of calcifications. The relationship between 3 levels of ICAC burden and procedural, clinical, and safety outcomes was analyzed. RESULTS: Among 86 patients meeting inclusion criteria, ICAC of any degree was present in 72.1 %. Median ICAC score was 3 [IQR 0-4]. There was a U-shaped association between ICAC score and successful reperfusion: 90.9 %, 65.7 %, and 94.4 % in the low, intermediate, and high ICAC score groups, respectively (p = 0.008). Use of rescue intervention, most often angioplasty and stenting, was greatest in the high ICAC score group: 3.0 % vs. 5.7 % vs. 22.2 % (p = 0.05). Functional independence at 90 days did not differ significantly among groups (41.7 % vs. 31.0 % vs. 15.4 %, p = 0.26), nor did rates of symptomatic intracranial hemorrhage (15.2 % vs. 14.3 % vs. 16.7 %, p = 0.97). CONCLUSIONS: ICAC is seen on CT in nearly three-quarters of patients with LVO-AIS. Extent of ICAC has a U-shaped association with successful reperfusion, in part due to more frequent use of rescue interventions in patients with extensive ICAC.

Collaterals at angiography guide clinical outcomes after endovascular stroke therapy in HERMES.

BACKGROUND: Robust collateral circulation has been linked with better reperfusion and clinical outcomes. It remains unclear how individual assessments of collateral circulation may be translated into clinical practice. METHODS: The pooled Highly Effective Reperfusion Evaluated in Multiple Endovascular Stroke Trials (HERMES) angiography dataset was analyzed by a centralized, independent imaging core blinded to other clinical data. Conventional angiography was acquired immediately prior to endovascular therapy. Collaterals were graded with the American Society of Interventional and Therapeutic Neuroradiology/Society of Interventional Radiology (ASITN) system and associated with baseline patient characteristics, reperfusion, and day 90 modified Rankin Score (mRS). Both 90-day all-cause mortality and day 90 mRS were modeled via multivariable logistic regression. RESULTS: Angiography was available in 376/605 (62%) patients. Baseline ASPECTS (Alberta Stroke Program Early CT Score) (p=0.043), history of diabetes mellitus (p=0.048), site of occlusion (p<0.001), and degree of subsequent Thrombolysis in Cerebral Infarction (TICI) reperfusion (p<0.001) were associated with collateral grades. ASITN collateral grade was strongly associated with ordinal mRS from baseline to 90 days in an unadjusted analysis (p<0.001). Multivariable regression demonstrated that collateral status is a strong determinant of mRS outcome in the presence of other predictors (OR=1.37 per grade, 95% CI [1.05 to 1.74], p=0.018). By comparing ORs, 1 unit of ASITN was determined to be approximately equivalent to 4.5 points of NIHSS, 11 years of age, 1.5 points of ASPECTS, or 100 min less delay from onset to puncture, in terms of impact on mRS. CONCLUSIONS: Individual collateral physiology may contribute significantly to reperfusion success and clinical outcomes after acute ischemic stroke. Building a consensus for the role of angiographic collateral assessment in the allocation of adjuvant reperfusion therapies may help galvanize a precision medicine approach in stroke.

Clinical presentation and treatment of 26 spinal epidural arteriovenous fistulas: a single-center experience.

BACKGROUND: Spinal epidural arteriovenous fistulas (SEDAVFs) are rarely diagnosed vascular malformations that can cause spinal cord compression and congestive myelopathy. METHODS: This is a single-center, retrospective case series of patients with SEDAVFs who underwent observation or treatment at UCLA medical center between 1993 and 2023. RESULTS: Between 1993 and 2023 a total of 26 patients at UCLA were found to have a SEDAVF. The median age at treatment was 59 years (range 4 months to 91 years). Compared with sacral, lumbar, and thoracic SEDAVFs, patients with cervical SEDAVF were younger (41 years vs 63 years, P=0.016) and more likely to be female (66.7% vs 14.3%, P=0.006). Possible triggers for development of SEDAVFs may be prior spinal surgery or trauma (n=4), turning the neck (n=1), lifting a heavy box (n=1), a prolonged period of bending over (n=1), and neurofibromatosis type 1 (n=1). Of the 22 patients treated endovascularly, 18 (82%) were angiographically cured on the first attempt without complications. One patient underwent surgical treatment alone and had a failed surgery on the first attempt, and developed a surgical site infection after the second successful attempt at treatment. Of the 16 patients with adequate clinical follow-up, 11 (69%) demonstrated early improved clinical outcome (eg, improved strength on examination, absent bruit). CONCLUSIONS: SEDAVFs are a rarely diagnosed disease that can be treated effectively and safely with endovascular embolization in most cases. Patients with sacral, lumbar, and thoracic SEDAVFs were older and more often male compared to patients with cervical SEDAVFs.

Intracranial aneurysm wall displacement depicted by amplified Flow predicts growth.

BACKGROUND: Abnormal intracranial aneurysm (IA) wall motion has been associated with IA growth and rupture. Recently, a new image processing algorithm called amplified Flow (aFlow) has been used to successfully track IA wall motion by combining the amplification of cine and four-dimensional (4D) Flow MRI. We sought to apply aFlow to assess wall motion as a potential marker of IA growth in a paired-wise analysis of patients with growing versus stable aneurysms. METHODS: In this retrospective case-control study, 10 patients with growing IAs and a matched cohort of 10 patients with stable IAs who had baseline 4D Flow MRI were included. The aFlow was used to amplify and extract IA wall displacements from 4D Flow MRI. The associations of aFlow parameters with commonly used risk factors and morphometric features were assessed using paired-wise univariate and multivariate analyses. RESULTS: aFlow quantitative results showed significantly (P=0.035) higher wall motion displacement depicted by mean±SD 90th% values of 2.34±0.72 in growing IAs versus 1.39±0.58 in stable IAs with an area under the curve of 0.85. There was also significantly (P<0.05) higher variability of wall deformation across IA geometry in growing versus stable IAs depicted by the dispersion variables including 121-150% larger standard deviation ([Formula: see text]) and 128-161% wider interquartile range [Formula: see text]. CONCLUSIONS: aFlow-derived quantitative assessment of IA wall motion showed greater wall motion and higher variability of wall deformation in growing versus stable IAs.

Arterial Bypass in the Treatment of Complex Middle Cerebral Artery Aneurysms: Lessons Learned from Forty Patients.

OBJECTIVE: Complex middle cerebral artery (MCA) aneurysms incorporating parent or branching vessels are often not amenable to standard microsurgical clipping or endovascular embolization treatments. We aim to discuss the treatment of such aneurysms via a combination of surgical revascularization and aneurysm exclusion based on our institutional experience. METHODS: Thirty-four patients with complex MCA aneurysms were treated with bypass and aneurysm occlusion, 5 with surgical clipping or wrapping only, and 1 with aneurysm excision and primary reanastomosis. Bypasses included superficial temporal artery (STA)-MCA, double-barrel STA-MCA, occipital artery-MCA, and external carotid artery-MCA. After bypass, aneurysms were treated by surgical clipping, Hunterian ligation, trapping, or coil embolization. RESULTS: The average age at diagnosis was 46 years. Of the aneurysms, 67% were large and most involved the MCA bifurcation. Most bypasses performed were STA-MCA bypasses, 12 of which were double-barrel. There were 2 wound-healing complications. All but 2 of the aneurysms treated showed complete occlusion at the last follow-up. There were 3 hemorrhagic complications, 3 graft thromboses, and 4 ischemic insults. The mean follow-up was 73 months. Of patients, 83% reported stable or improved symptoms from presentation and 73% reported a functional status (Glasgow Outcome Scale score 4 or 5) at the latest available follow-up. CONCLUSIONS: Cerebral revascularization by bypass followed by aneurysm or parent artery occlusion is an effective treatment option for complex MCA aneurysms that cannot be safely treated by standard microsurgical or endovascular techniques. Double-barrel bypass consisting of 2 STA branches to 2 MCA branches yields adequate flow replacement in most cases.

Automated assessment of ischemic core on non-contrast computed tomography: a multicenter comparative analysis with CT perfusion.

BACKGROUND: Application of machine learning (ML) algorithms has shown promising results in estimating ischemic core volumes using non-contrast CT (NCCT). OBJECTIVE: To assess the performance of the e-Stroke Suite software (Brainomix) in assessing ischemic core volumes on NCCT compared with CT perfusion (CTP) in patients with acute ischemic stroke. METHODS: In this retrospective multicenter study, patients with anterior circulation large vessel occlusions who underwent pretreatment NCCT and CTP, successful reperfusion (modified Thrombolysis in Cerbral Infarction ≥2b), and post-treatment MRI, were included from three stroke centers. Automated calculation of ischemic core volumes was obtained on NCCT scans using ML algorithm deployed by e-Stroke Suite and from CTP using Olea software (Olea Medical). Comparative analysis was performed between estimated core volumes on NCCT and CTP and against MRI calculated final infarct volume (FIV). RESULTS: A total of 111 patients were included. Estimated ischemic core volumes (mean±SD, mL) were 20.4±19.0 on NCCT and 19.9±18.6 on CTP, not significantly different (P=0.82). There was moderate (r=0.40) and significant (P<0.001) correlation between estimated core on NCCT and CTP. The mean difference between FIV and estimated core volume on NCCT and CTP was 29.9±34.6 mL and 29.6±35.0 mL, respectively (P=0.94). Correlations between FIV and estimated core volume were similar for NCCT (r=0.30, P=0.001) and CTP (r=0.36, P<0.001). CONCLUSIONS: Results show that ML-based estimated ischemic core volumes on NCCT are comparable to those obtained from concurrent CTP in magnitude and in degree of correlation with MR-assessed FIV.

Perfusion Collateral Index versus Hypoperfusion Intensity Ratio in Assessment of Collaterals in Patients with Acute Ischemic Stroke.

BACKGROUND AND PURPOSE: Perfusion-based collateral indices such as the perfusion collateral index and the hypoperfusion intensity ratio have shown promise in the assessment of collaterals in patients with acute ischemic stroke. We aimed to compare the diagnostic performance of the perfusion collateral index and the hypoperfusion intensity ratio in collateral assessment compared with angiographic collaterals and outcome measures, including final infarct volume, infarct growth, and functional independence. MATERIALS AND METHODS: Consecutive patients with acute ischemic stroke with anterior circulation proximal arterial occlusion who underwent endovascular thrombectomy and had pre- and posttreatment MRI were included. Using pretreatment MR perfusion, we calculated the perfusion collateral index and the hypoperfusion intensity ratio for each patient. The angiographic collaterals obtained from DSA were dichotomized to sufficient (American Society of Interventional and Therapeutic Neuroradiology [ASITN] scale 3-4) versus insufficient (ASITN scale 0-2). The association of collateral status determined by the perfusion collateral index and the hypoperfusion intensity ratio was assessed against angiographic collaterals and outcome measures. RESULTS: A total of 98 patients met the inclusion criteria. Perfusion collateral index values were significantly higher in patients with sufficient angiographic collaterals (P < .001), while there was no significant (P = .46) difference in hypoperfusion intensity ratio values. Among patients with good (mRS 0-2) versus poor (mRS 3-6) functional outcome, the perfusion collateral index of ≥ 62 was present in 72% versus 31% (P = .003), while the hypoperfusion intensity ratio of ≤0.4 was present in 69% versus 56% (P = .52). The perfusion collateral index and the hypoperfusion intensity ratio were both significantly predictive of final infarct volume, but only the perfusion collateral index was significantly (P = .03) associated with infarct growth. CONCLUSIONS: Results show that the perfusion collateral index outperforms the hypoperfusion intensity ratio in the assessment of collateral status, infarct growth, and determination of functional outcomes.

Proximal Internal Carotid Artery Occlusion and Extracranial-Intracranial Bypass for Treatment of Fusiform and Giant Internal Carotid Artery Aneurysms.

OBJECTIVE: To discuss the treatment of intracranial fusiform and giant internal carotid artery (ICA) aneurysms via revascularization based on our institutional experience. METHODS: An institutional review board-approved retrospective analysis was performed of patients with unruptured fusiform and giant intracranial ICA aneurysms treated from November 1991 to May 2020. All patients were evaluated for extracranial-intracranial (EC-IC) bypass and ICA occlusion. RESULTS: Thirty-eight patients were identified. Initially, patients failing preoperative balloon test occlusion were treated with superficial temporal artery (STA)-middle cerebral artery (MCA) bypass and concurrent proximal ICA ligation. We then treated them with STA-MCA bypass, followed by staged balloon test occlusion, and, if they passed, endovascular ICA coil occlusion. We treat all surgical medically uncomplicated patients with double-barrel STA-MCA bypass and concurrent proximal ICA ligation. The mean length of follow-up was 99 months. Symptom stability or improvement was noted in 85% of patients. Bypass graft patency was 92.1%, and all surviving patients had patent bypasses at their last angiogram. Aneurysm occlusion was complete in 90.9% of patients completing proximal ICA ligation. Three patients experienced ischemic complications and 4 patients experienced hemorrhagic complications. CONCLUSIONS: Not all fusiform intracranial ICA aneurysms require intervention, except when life-threatening rupture risk is high or symptomatic management is necessary to preserve function and quality of life. EC-IC bypass can augment the safety of proximal ICA occlusion. The rate of complete aneurysm occlusion with this treatment is 90.9%, and long-term bypass graft-related complications are rare. Perioperative stroke is a major risk, and continued evolution of treatment is required.

Robotic Diagnostic Cerebral Angiography: A Multicenter Experience of 113 Patients.

BACKGROUND: Neurointerventional robotic systems have potential to reduce occupational radiation, improve procedural precision, and allow for future remote teleoperation. A limited number of single institution case reports and series have been published outlining the safety and feasibility of robot-assisted diagnostic cerebral angiography. METHODS: This is a multicenter, retrospective case series of patients undergoing diagnostic cerebral angiography at three separate institutions - University of California, Davis (UCD); University of California, Los Angeles (UCLA); and University of California, San Francisco (UCSF). The equipment used was the CorPath GRX Robotic System (Corindus, Waltham, MA). RESULTS: A total of 113 cases were analyzed who underwent robot-assisted diagnostic cerebral angiography from September 28, 2020 to October 27, 2022. There were no significant complications related to use of the robotic system including stroke, arterial dissection, bleeding, or pseudoaneurysm formation at the access site. Using the robotic system, 88 of 113 (77.9%) cases were completed successfully without unplanned manual conversion. The principal causes for unplanned manual conversion included challenging anatomy, technical difficulty with the bedside robotic cassette, and hubbing out of the robotic system due to limited working length. For robotic operation, average fluoroscopy time was 13.2 min (interquartile range (IQR), 9.3 to 16.8 min) and average cumulative air kerma was 975.8 mGY (IQR, 350.8 to 1073.5 mGy). CONCLUSIONS: Robotic cerebral angiography with the CorPath GRX Robotic System is safe and easily learned by novice users without much prior manual experience. However, there are technical limitations such as a short working length and an inability to support 0.035" wires which may limit its widespread adoption in clinical practice.

Aneurysmal subarachnoid hemorrhage in pregnancy: National trends of treatment, predictors, and outcomes.

INTRODUCTION: Aneurysmal subarachnoid hemorrhage (aSAH) is a rare event associated with significant pregnancy-associated maternal and neonatal morbidity and mortality. The optimal treatment strategy and clinical outcome of aSAH in pregnancy remains unclear. We aimed to investigate the treatment utilizations and outcomes of aSAH in pregnant people. METHODS: Using the 2010-2018 National Inpatient Sample, we identified all birth hospitalizations of women between ages of 18 to 45 associated with subarachnoid hemorrhage and aneurysm treatment were included. Multivariate analyses were used to evaluate the effect of pregnancy state, mode of treatment of aneurysms, severity of subarachnoid hemorrhage on mortality and discharge destination of this cohort. Trends in mode of treatment utilized for aneurysmal treatment in this time interval was evaluated. RESULTS: 13,351 aSAH with treatment were identified, of which 440 were associated with pregnancy. There was no significant difference in mortality or rate of discharge to home in pregnancy related hospitalization. Worse aSAH severity, chronic hypertension, and smaller hospital size was associated with significantly higher rate of mortality from aSAH during pregnancy. Worse aSAH severity was associated with lower rate of discharge to home. Like the non-pregnant cohort, the treatment of ruptured aneurysms in pregnancy are increasingly through endovascular approaches. The mode of treatment does not change the mortality or discharge destination. CONCLUSIONS: Pregnancy does not alter mortality or the discharge destination for aSAH. Ruptured aneurysms during pregnancy are increasingly treated endovascularly. Mode of aneurysm treatment does not affect mortality or discharge destination in pregnancy.

Risk factors of unexplained early neurological deterioration after treatment for ischemic stroke due to large vessel occlusion: a post hoc analysis of the HERMES study.

BACKGROUND: Early neurological deterioration (END) after endovascular treatment (EVT) in patients with anterior circulation acute ischemic stroke (AIS) is associated with poor outcome. END may remain unexplained by parenchymal hemorrhage (UnEND). We aim to analyze the risk factors of UnEND in the medical management (MM) and EVT arms of the HERMES study. METHODS: We conducted a post-hoc analysis of anterior AIS patients who underwent EVT for proximal anterior occlusions. Risk factors of UnEND, defined as a worsening of ≥4 points between baseline National Institutes of Health Stroke Scale (NIHSS) and NIHSS at 24 hours without hemorrhage, were compared between both arms using mixed logistic regression models adjusted for baseline characteristics. An interaction analysis between the EVT and MM arms for risk factors of UnEND was conducted. RESULTS: Among 1723 patients assessable for UnEND, 160 patients experienced an UnEND (9.3%), including 9.1% (78/854) in the EVT arm and 9.4% (82/869) in the MM arm. There was no significant difference in the incidence of UnEND between the two study arms. In the EVT population, independent risk factors of UnEND were lower baseline NIHSS, higher baseline glucose, and lower collateral grade. In the MM population, the only independent predictor of UnEND was higher baseline glucose. However, we did not demonstrate an interaction between EVT and MM for baseline factors as risk factors of UnEND. UnEND was, similarly in both treatment groups, a significant predictor of unfavorable outcome in both the EVT (p<0.001) and MM (p<0.001) arms. CONCLUSIONS: UnEND is not an uncommon event, with a similar rate which ever treatment arm is considered. In the clinical scenario of AIS due to large vessel occlusion, no patient-related factor seems to increase the risk for UnEND when treated by EVT compared with MM.

Automated estimation of ischemic core volume on noncontrast-enhanced CT via machine learning.

BACKGROUND: Accurate estimation of ischemic core on baseline imaging has treatment implications in patients with acute ischemic stroke (AIS). Machine learning (ML) algorithms have shown promising results in estimating ischemic core using routine noncontrast computed tomography (NCCT). OBJECTIVE: We used an ML-trained algorithm to quantify ischemic core volume on NCCT in a comparative analysis to pretreatment magnetic resonance imaging (MRI) diffusion-weighted imaging (DWI) in patients with AIS. METHODS: Patients with AIS who had both pretreatment NCCT and MRI were enrolled. An automatic segmentation ML approach was applied using Brainomix software (Oxford, UK) to segment the ischemic voxels and calculate ischemic core volume on NCCT. Ischemic core volume was also calculated on baseline MRI DWI. Comparative analysis was performed using Bland-Altman plots and Pearson correlation. RESULTS: A total of 72 patients were included. The time-to-stroke onset time was 134.2/89.5 minutes (mean/median). The time difference between NCCT and MRI was 64.8/44.5 minutes (mean/median). In patients who presented within 1 hour from stroke onset, the ischemic core volumes were significantly (p = 0.005) underestimated by ML-NCCT. In patients presented beyond 1 hour, the ML-NCCT estimated ischemic core volumes approximated those obtained by MRI-DWI and with significant correlation (r = 0.56, p < 0.001). CONCLUSION: The ischemic core volumes calculated by the described ML approach on NCCT approximate those obtained by MRI in patients with AIS who present beyond 1 hour from stroke onset.

MR Angiography in Assessment of Collaterals in Patients with Acute Ischemic Stroke: A Comparative Analysis with Digital Subtraction Angiography.

Collateral status has prognostic and treatment implications in acute ischemic stroke (AIS) patients. Unlike CTA, grading collaterals on MRA is not well studied. We aimed to evaluate the accuracy of assessing collaterals on pretreatment MRA in AIS patients against DSA. AIS patients with anterior circulation proximal arterial occlusion with baseline MRA and subsequent endovascular treatment were included. MRA collaterals were evaluated by two neuroradiologists independently using the Tan and Maas scoring systems. DSA collaterals were evaluated by using the American Society of Interventional and Therapeutic Neuroradiology grading system and were used as the reference for comparative analysis against MRA. A total of 104 patients met the inclusion criteria (59 female, age (mean ± SD): 70.8 ± 18.1). The inter-rater agreement (k) for collateral scoring was 0.49, 95% CI 0.37-0.61 for the Tan score and 0.44, 95% CI 0.26-0.62 for the Maas score. Total number (%) of sufficient vs. insufficient collaterals based on DSA was 49 (47%) and 55 (53%) respectively. Using the Tan score, 45% of patients with sufficient collaterals and 64% with insufficient collaterals were correctly identified in comparison to DSA, resulting in a poor agreement (0.09, 95% CI 0.1-0.28). Using the Maas score, only 4% of patients with sufficient collaterals and 93% with insufficient collaterals were correctly identified against DSA, resulting in poor agreement (0.03, 95% CI 0.06-0.13). Pretreatment MRA in AIS patients has limited concordance with DSA when grading collaterals using the Tan and Maas scoring systems.

The "Bright Falx" Sign-Midline Embolic Penetration Is Associated With Faster Resolution of Chronic Subdural Hematoma After Middle Meningeal Artery Embolization: A Case Series.

BACKGROUND: Chronic subdural hematomas (CSDHs) are common in the elderly population and patients taking antiplatelet/anticoagulation medications. Middle meningeal artery (MMA) embolization has become an adjunctive treatment to observation and surgery. Despite many embolization techniques, best practices for optimal CSDH resolution remain unknown. OBJECTIVE: To report a retrospective case series of MMA embolization for CSDHs regarding rate of hematoma improvement and the significance of distal embolic penetration into the falx. METHODS: Retrospective chart review was performed on all patients who underwent MMA embolization for CSDHs between January 2017 and June 2021. Patient demographics, clinical presentation, anticoagulant use, and radiographic features were collected. Pre-embolization and postembolization computed tomography scans were analyzed for volumetric changes and assessed for midline penetration of embolic material in the falx. RESULTS: MMA embolization was performed in 37 patients and 53 hemispheres. Older patients took longer to obtain complete resolution of CSDHs (r = 0.47, P = .03). Patients with larger pre-embolization (r = 0.57, P = .007) and postembolization (r = 0.56, P = .008) CSDH volumes took longer to completely resolve. Patients who had n-butyl cyanoacrylate embolization with midline penetration, as evidenced by the "bright falx" sign, had faster improvement rates than those who did not (5.64 cm 3 /d vs 1.2 cm 3 /d, P = .02). CONCLUSION: Distal penetration of embolic material, particularly n-butyl cyanoacrylate, into the falx may lead to more rapid improvement of CSDH.

Critical Angiographic and Sonographic Analysis of Intra Aneurysmal and Downstream Hemodynamic Changes After Flow Diversion.

Introduction: Successful treatment of intracranial aneurysms after flow diversion (FD) is dependent on the flow modulating effect of the device. We aimed to investigate the intra-aneurysmal and parent vessel hemodynamic changes, as well as the incidence of silent emboli following treatment with various FD devices. Methods: We evaluated the appearance of the eclipse sign in nine distinct phases of cerebral angiography before and immediately after FD placement in correlation with aneurysm occlusion. Angiographic and clinical data of consecutive procedures were analyzed retrospectively. Patients who had successful FD procedure without adjunctive coiling, visible eclipse sign on post embolization angiography, and reliable follow-up angiographic data were included in the analysis. Detailed analysis of hemodynamic data from transcranial doppler after FD was performed in selected patients, such as monitoring for silent emboli. Results: Among all patients (N = 65) who met inclusion criteria, complete aneurysm occlusion at 12 months was achieved in 89% (58/65). Eclipse sign prior to FD was observed in 42% (27/65) with unchanged appearance in 4.6% (3/65) of the treated patients. None of these three patients achieved complete aneurysm occlusion. Among all analyzed variables, such as aneurysm size, device type used, age, and appearance of the eclipse sign pre- and post-FD, the most reliable predictor of permanent aneurysm occlusion at 12 months was earlier, prolonged, and sustained eclipse sign visibility in more than three angiographic phases in comparison to the baseline (p < 0.001). Elevation in flow velocities within the ipsilateral vascular territory was noted in 70% (9/13), and bilaterally in 54% (7/13) of the treated patients. None of the patients had silent emboli. Conclusions: Intra-aneurysmal and parent vessel hemodynamic changes after FD can be reliably assessed by the cerebral angiography and transcranial doppler with important implications for the prediction of successful treatment.

Stent Retriever Thrombectomy for Anterior vs. Posterior Circulation Ischemic Stroke: Analysis of the STRATIS Registry.

Background and Purpose: The benefits of mechanical thrombectomy (MT) in vertebrobasilar artery occlusions have not been well-studied. We compared clinical, procedural, and safety outcomes of MT for posterior circulation (PC) vs. anterior circulation (AC) occlusions among patients in the STRATIS registry. Methods: Data from STRATIS including patient demographics, procedural characteristics, and outcomes including symptomatic intracranial hemorrhage (sICH) at 24 h, serious adverse events (SAE), substantial reperfusion [modified thrombolysis in cerebral infarction (mTICI) 2b/3], 90-day functional independence [modified Rankin Scale (mRS) 0-2], and 90-day mortality were analyzed. Univariate logistic regression was used to calculate predictors of good clinical outcome. Results: Of 984 STRATIS patients, 43 (4.4%) patients with PC occlusions [mean age 63.0 ± 13.6, 25.6% (11/43) female] and 932 (94.7%) with AC occlusions [mean age 68.5 ± 14.8, 46.9% (437/932) female] were included for analysis. Median National Institutes of Health Stroke Scale (NIHSS) scores at baseline were 17.0 (13.0, 12.0) for the AC group and 12.0 (11.0, 24.0) for the PC group. Time from onset to procedure end was longer for the PC group [median (IQR): 322.0 min (255.0-421.0) vs. 271.0 min (207.0-360.0); p = 0.007]. PC and AC groups had similar rates of substantial reperfusion [89.2% (33/37) vs. 87.7% (684/780)], procedure-related SAE [0.0% (0/43) vs. 1.7% (16/932)], sICH [0.0% (0/38) vs. 1.5% (12/795)], 90-day functional independence [66.7% (26/39) vs. 55.9% (480/858)] and mortality [12.8% (5/39) vs. 15.8% (136/861)]. National Institutes of Health Stroke Scale score and patient sex were significant univariate predictors of good clinical outcome (p < 0.05). Conclusions: Despite longer reperfusion times, MT in PC stroke has similar rates of 90-day functional independence with no significant difference in procedure-related SAE, sICH, or mortality, supporting the use of MT in PC acute ischemic stroke (AIS). Clinical Trial Registration:https://www.clinicaltrials.gov, Identifier: NCT02239640.

Impact of Age and Alberta Stroke Program Early Computed Tomography Score 0 to 5 on Mechanical Thrombectomy Outcomes: Analysis From the STRATIS Registry.

BACKGROUND AND PURPOSE: This study investigates clinical outcomes after mechanical thrombectomy in adult patients with baseline Alberta Stroke Program Early CT Score (ASPECTS) of 0 to 5. METHODS: We included data from the STRATIS Registry (Systematic Evaluation of Patients Treated With Neurothrombectomy Devices for Acute Ischemic Stroke) from patients who underwent mechanical thrombectomy within 8 hours of symptom onset and had available ASPECTS data adjudicated by an independent core laboratory. Angiographic and clinical outcomes were collected, including successful reperfusion (modified Thrombolysis in Cerebral Infarction ≥2b), functional independence (modified Rankin Scale score 0-2), 90-day mortality, and symptomatic intracranial hemorrhage at 24 hours. Outcomes were stratified by ASPECTS scores and age. RESULTS: Of the 984 patients enrolled, 763 had available ASPECTS data. Of these patients, 57 had ASPECTS of 0 to 5 with a median age of 63 years (interquartile range, 28-100), whereas 706 patients had ASPECTS of 6 to 10 with a median age of 70 years of age (interquartile range, 19-100). Ten patients had ASPECTS of 0 to 3 and 47 patients had ASPECTS of 4 to 5 at baseline. Successful reperfusion was achieved in 85.5% (47/55) in the ASPECTS of 0 to 5 group. Functional independence was achieved in 28.8% (15/52) in the ASPECTS of 0 to 5 versus 59.7% (388/650) in the 6 to 10 group (P<0.001). Mortality rates were 30.8% (16/52) in the ASPECTS of 0 to 5 and 13.4% (87/650) in the 6 to 10 group (P<0.001). sICH rates were 7.0% (4/57) in the ASPECTS of 0 to 5 and 0.9% (6/682) in the 6 to 10 group (P<0.001). No patients aged >75 years with ASPECTS of 0 to 5 (0/12) achieved functional independence versus 44.8% (13/29) of those age ≤65 (P=0.005). CONCLUSIONS: Patients <65 years of age with large core infarction (ASPECTS 0-5) have better rates of functional independence and lower rates of mortality compared with patients >75 years of age. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT02239640.

Frequency, Determinants, and Outcomes of Emboli to Distal and New Territories Related to Mechanical Thrombectomy for Acute Ischemic Stroke.

Background and Purpose: Clot fragmentation and distal embolization during endovascular thrombectomy for acute ischemic stroke may produce emboli downstream of the target occlusion or in previously uninvolved territories. Susceptibility-weighted magnetic resonance imaging can identify both emboli to distal territories (EDT) and new territories (ENT) as new susceptibility vessel signs (SVS). Diffusion-weighted imaging (DWI) can identify infarcts in new territories (INT). Methods: We studied consecutive acute ischemic stroke patients undergoing magnetic resonance imaging before and after thrombectomy. Frequency, predictors, and outcomes of EDT and ENT detected on gradient-recalled echo imaging (EDT-SVS and ENT-SVS) and INT detected on DWI (INT-DWI) were analyzed. Results: Among 50 thrombectomy-treated acute ischemic stroke patients meeting study criteria, mean age was 70 (±16) years, 44% were women, and presenting National Institutes of Health Stroke Scale score 15 (interquartile range, 8­19). Overall, 21 of 50 (42%) patients showed periprocedural embolic events, including 10 of 50 (20%) with new EDT-SVS, 10 of 50 (20%) with INT-DWI, and 1 of 50 (2%) with both. No patient showed ENT-SVS. On multivariate analysis, model-selected predictors of EDT-SVS were lower initial diastolic blood pressure (odds ratio, 1.09 [95% CI, 1.02­1.16]), alteplase pretreatment (odds ratio, 5.54 [95% CI, 0.94­32.49]), and atrial fibrillation (odds ratio, 7.38 [95% CI, 1.02­53.32]). Classification tree analysis identified pretreatment target occlusion SVS as an additional predictor. On univariate analysis, INT-DWI was less common with internal carotid artery (5%), intermediate with middle cerebral artery (25%), and highest with vertebrobasilar (57%) target occlusions (P=0.02). EDT-SVS was not associated with imaging/functional outcomes, but INT-DWI was associated with reduced radiological hemorrhagic transformation (0% versus 54%; P<0.01). Conclusions: Among acute ischemic stroke patients treated with thrombectomy, imaging evidence of distal emboli, including EDT-SVS beyond the target occlusion and INT-DWI in novel territories, occur in about 2 in every 5 cases. Predictors of EDT-SVS are pretreatment intravenous fibrinolysis, potentially disrupting thrombus structural integrity; atrial fibrillation, possibly reflecting larger target thrombus burden; lower diastolic blood pressure, suggestive of impaired embolic washout; and pretreatment target occlusion SVS sign, indicating erythrocyte-rich, friable target thrombus.

Role of Intravenous Tissue Plasminogen Activator in Acute Ischemic Stroke with Large Vessel Occlusion.

OBJECTIVE: The goal of the present study was to determine the safety and efficacy of intravenous tissue plasminogen activator (IVT) in patients with acute ischemic stroke (AIS) with large vessel occlusion (LVO) undergoing mechanical thrombectomy (MT). METHODS: We performed a retrospective analysis of prospectively collected data gathered during a 3-year period for all our patients with AIS and LVO. We analyzed the stroke outcomes and complications between patients who had received a combination of IVT and MT and those who had undergone MT only. Standardized selection criteria, including the uniform use of perfusion imaging, were used for selection for MT, irrespective of IVT administration. RESULTS: Of the patients who had received IVT, 10% had had successful reperfusion found at initial angiography and did not require MT. A door-to-puncture time within 1 hour of presentation was achieved in 19% of both groups. IVT+MT was not associated with an increased incidence of intracranial hemorrhage (IVT+MT, 47.1%; MT, 49%). Of the 73 patients in IVT+MT group, 8 had developed access-site hematomas compared with 9 of the 95 patients in the MT group (28.6% vs. 26.5%; P = 0.85). The IVT+MT group had a lower proportion of patients with a modified Rankin scale score of 5-6 at 90 days compared with the MT group (36% vs. 56%; P = 0.024). Both groups showed statistically similar proportions of patients with a Thrombolysis in Cerebral Infarction scale score of ≥2c (IVT+MT, 50%; MT, 43%; P = 0.58). The IVT+MT group had a greater proportion of patients with Thrombolysis in Cerebral Infarction scale score of 2c (IVT+MT, 29.6%; MT, 16.8%; P = 0.068). CONCLUSIONS: Administration of IVT before MT to patients with AIS with LVO resulted in reperfusion before MT in 10% of patients, reduced the incidence of mortality and severe disability at 90 days, did not affect the door-to-puncture time, and was associated with a similar incidence of systemic and intracranial hemorrhage compared with MT only.

Impact of eloquent motor cortex-tissue reperfusion beyond the traditional thrombolysis in cerebral infarction (TICI) scoring after thrombectomy.

BACKGROUND: Targeted eloquence-based tissue reperfusion within the primary motor cortex may have a differential effect on disability as compared with traditional volume-based (thrombolysis in cerebral infarction, TICI) reperfusion after endovascular thrombectomy (EVT) in the setting of acute ischemic stroke (AIS). METHODS: We explored the impact of eloquent reperfusion (ER) within primary motor cortex (PMC) on clinical outcome (modified Rankin Scale, mRS) in AIS patients undergoing EVT. ER-PMC was defined as presence of flow on final digital subtraction angiography (DSA) within four main cortical branches, supplying the PMC (middle cerebral artery (MCA) - precentral, central, postcentral; anterior cerebral artery (ACA) - medial frontal branch arising from callosomarginal or pericallosal arteries) and graded as absent (0), partial (1), and complete (2). Prospectively collected data from two centers were analyzed. Multivariate analysis was conducted to assess the impact of ER-PMC on 90-day disability (mRS) among patients with anterior circulation occlusion who achieved partial reperfusion (TICI 2a and 2b). RESULTS: Among the 125 patients who met the study criteria, ER-PMC distribution was: absent (0) in 19/125 (15.2%); partial (1) in 52/125 (41.6%), and complete (2) in 54/125 (43.2%). TICI 2b was achieved in 102/125 (81.6%) and ER-PMC was substantially higher in those patients (P<0.001). In multivariate analysis, in addition to age and symptomatic intracranial hemorrhage, ER-PMC had a profound independent impact on 90-day disability (OR 6.10, P=0.001 for ER-PMC 1 vs 0 and OR 9.87, P<0.001 for ER-PMC 2 vs 0), while the extent of total partial reperfusion (TICI 2b vs 2a) was not related to 90-day mRS. CONCLUSIONS: Eloquent PMC-tissue reperfusion is a key determinant of functional outcome, with a greater impact than volume-based (TICI) degree of partial reperfusion alone. PMC-targeted revascularization among patients with partial reperfusion may further diminish post-stroke disability after EVT.