Endovascular thrombectomy for large ischemic strokes: An updated living systematic review and meta-analysis of randomized clinical trials

BACKGROUND

Recent studies indicate endovascular thrombectomy (EVT) as a safe, effective treatment for acute ischemic stroke (AIS) with large ischemic regions. Our study updates an ongoing living systematic review and meta-analysis of randomized controlled trials (RCTs) comparing outcomes of EVT to medical management only.

METHODS

We searched MEDLINE, EMBASE, and the Cochrane Library for RCTs comparing EVT to medical management in AIS patients with large ischemic areas. Using fixed-effect models, we conducted a meta-analysis to compare functional independence, mortality, and symptomatic intracranial hemorrhage (sICH) between EVT and standard medical management. We evaluated bias risk with the Cochrane tool and graded the certainty of evidence using the GRADE approach.

RESULTS

Of 1363 new citations, we included six RCTs with a total of 1876 patients. We found low-certainty evidence of improved functional independence (risk difference [RD] 29.9%, 95% CI 17.2% to 46.9%), increase in sICH (RD 2.6%, 95% CI 0.3% to 6.4%), and a non-significant decrease in mortality (RD -1.8%, 95% CI -3.9% to 0.6%) for AIS patients with large infarcts who underwent EVT compared to medical management only.

CONCLUSION

Our revised meta-analysis suggests low-certainty evidence that there is improved functional independence, a non-significant decrease in mortality, and an increase in sICH among AIS patients with large infarcts who undergo EVT compared to those receiving medical management alone.

SYSTEMATIC REVIEW PROTOCOL REGISTRATION

PROSPERO (CRD42023398742).

Factors Affecting Selection of TraineE for Neurointervention (FASTEN)

BACKGROUND AND IMPORTANCE

Neurointervention is a very competitive specialty in the United States due to the limited number of training spots and the larger pool of applicants. The training standards are continuously updated to ensure solid training experiences. Factors affecting candidate(s) selection have not been fully established yet. Our study aims to investigate the factors influencing the selection process.

METHODS

A 52-question survey was distributed to 93 program directors (PDs). The survey consisted of six categories: (a) Program characteristics, (b) Candidate demographics, (c) Educational credentials, (d) Personal traits, (e) Research and extracurricular activities, and (f) Overall final set of characteristics. The response rate was 59.1%. As per the programs' characteristics, neurosurgery was the most involved specialty in running the training programs (69%). Regarding demographics, the need for visa sponsorship held the greatest prominence with a mean score of 5.9 [standard deviation (SD) 2.9]. For the educational credentials, being a graduate from a neurosurgical residency and the institution where the candidate's residency training is/was scored the highest [5.4 (SD = 2.9), 5.4 (SD = 2.5), respectively]. Regarding the personal traits, assessment by faculty members achieved the highest score [8.9 (SD = 1)]. In terms of research/extracurricular activities, fluency in English had the highest score [7.2 (SD = 1.9)] followed by peer-reviewed/PubMed-indexed publications [6.4 (SD = 2.2)].

CONCLUSION

Our survey investigated the factors influencing the final decision when choosing the future neurointerventional trainee, including demographic, educational, research, and extracurricular activities, which might serve as valuable guidance for both applicants and programs to refine the selection process.

Endovascular intervention for the treatment of epistaxis: cone beam CT review of anatomy, collateral, and treatment implications/efficacy

Epistaxis is common, impacting more than half the population, and can require procedural intervention in approximately 10% of cases. With an aging population and increasing use of antiplatelets and anticoagulants, severe epistaxis is likely to increase in frequency significantly over the next two decades. Sphenopalatine artery embolization is rapidly becoming the most common type of procedural intervention. The efficacy of endovascular embolization is dependent on a refined understanding of the anatomy and collateral physiology of this circulation as well as the impact of temporizing measures such as nasal packing and inflation of a nasal balloon. Likewise, safety is dependent on a detailed appreciation of collateralization with the internal carotid artery and ophthalmic artery. Cone beam CT imaging has the resolution to enable a clear visualization of the anatomy and collateral circulation associated with the arterial supply to the nasal cavity, in addition to assisting with hemorrhage localization. We present a review of epistaxis treatment, a detailed description of anatomic and physiologic considerations informed by cone beam CT imaging, and a proposed protocol for sphenopalatine embolization for which there is currently no standard.

Cerebral Ischemic Reperfusion Injury: Preventative and Therapeutic Strategies

Acute ischemic stroke is a leading cause of morbidity and mortality in the United States. Treatment goals remain focused on restoring blood flow to compromised areas. However, a major concern arises after reperfusion occurs. Cerebral ischemic reperfusion injury is defined as damage to otherwise salvageable brain tissue occurring with the reestablishment of the vascular supply to that region. The pool of eligible patients for revascularization continues to grow, especially with the recently expanded endovascular therapeutic window. Neurointensivists should understand and manage complications of successful recanalization. In this review, we examine the pathophysiology, diagnosis, and potential management strategies in cerebral ischemic reperfusion injury.

Neuroendovascular Surgery Applications in Craniocervical Trauma

Cerebrovascular injuries resulting from blunt or penetrating trauma to the head and neck often lead to local hemorrhage and stroke. These injuries present with a wide range of manifestations, including carotid or vertebral artery dissection, pseudoaneurysm, occlusion, transection, arteriovenous fistula, carotid-cavernous fistula, epistaxis, venous sinus thrombosis, and subdural hematoma. A selective review of the literature from 1989 to 2023 was conducted to explore various neuroendovascular surgical techniques for craniocervical trauma. A PubMed search was performed using these terms: endovascular, trauma, dissection, blunt cerebrovascular injury, pseudoaneurysm, occlusion, transection, vasospasm, carotid-cavernous fistula, arteriovenous fistula, epistaxis, cerebral venous sinus thrombosis, subdural hematoma, and middle meningeal artery embolization. An increasing array of neuroendovascular procedures are currently available to treat these traumatic injuries. Coils, liquid embolics (onyx or n-butyl cyanoacrylate), and polyvinyl alcohol particles can be used to embolize lesions, while stents, mechanical thrombectomy employing stent-retrievers or aspiration catheters, and balloon occlusion tests and super selective angiography offer additional treatment options based on the specific case. Neuroendovascular techniques prove valuable when surgical options are limited, although comparative data with surgical techniques in trauma cases is limited. Further research is needed to assess the efficacy and outcomes associated with these interventions.

Significant Mortality Associated With COVID-19 and Comorbid Cerebrovascular Disease: A Quantitative Systematic Review

We report the first quantitative systematic review of cerebrovascular disease in coronavirus disease 2019 (COVID-19) to provide occurrence rates and associated mortality. Through a comprehensive search of PubMed we identified 8 cohort studies, 5 case series, and 2 case reports of acute cerebrovascular disease in patients with confirmed COVID-19 diagnosis. Our first meta-analysis utilizing the identified publications focused on comorbid cerebrovascular disease in recovered and deceased patients with COVID-19. We performed 3 additional meta-analyses of proportions to produce point estimates of the mortality and incidence of acute cerebrovascular disease in COVID-19 patients. Patient's with COVID-19 who died were 12.6 times more likely to have a history of cerebrovascular disease. We estimated an occurrence rate of 2.6% (95% confidence interval, 1.2-5.4%) for acute cerebrovascular disease among consecutively admitted patients with COVID-19. While for those with severe COVID-19' we estimated an occurrence rate of 6.5% (95% confidence interval, 4.4-9.6%). Our analysis estimated a rate of 35.5% for in-hospital mortality among COVID-19 patients with concomitant acute cerebrovascular disease. This was consistent with a mortality rate of 34.0% which we obtained through an individual patient analysis of 47 patients derived from all available case reports and case series. COVID-19 patients with either acute or chronic cerebrovascular disease have a high mortality rate with higher occurrence of cerebrovascular disease in patients with severe COVID-19.

Intravenous thrombolysis plus mechanical thrombectomy versus mechanical thrombectomy alone for acute ischemic stroke: A systematic review and updated meta-analysis of clinical trials

BACKGROUND

Mechanical thrombectomy (MT) is the gold standard treatment for large vessel occlusion (LVO). A vital factor that might influence MT outcomes is the use of intravenous thrombolysis (IVT). A few clinical trials in this domain thus far have not yielded consistent outcomes. We conducted this meta-analysis to synthesize collective evidence in this regard.

METHODS

The Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) statement guidelines were followed, and we performed a comprehensive literature search of four databases (PubMed, Scopus, Web of Science, Cochrane CENTRAL). For outcomes constituting continuous data, the mean difference (MD) and its standard deviation (SD) were pooled. For outcomes constituting dichotomous data, the frequency of events and the total number of patients were pooled as the risk ratio (RR).

RESULTS

Seven clinical trials with a total of 2317 patients are included in this meta-analysis. Six trials are randomized, and one trial was nonrandomized. No significant differences were found between MT plus IVT and MT alone in successful recanalization (RR 1.04, 95% Confidence Interval (CI) [0.92 to 1.17], P = 0.53), 90-day functional independence (RR 1.03, 95% CI [0.90 to 1.19], P = 0.65), symptomatic intracranial hemorrhage (sICH) (RR 1.22, 95% CI [0.84 to 1.75], P = 0.30), or mortality (RR 0.94, 95% CI [0.76 to 1.18], P = 0.61).

CONCLUSION

The current evidence does not favor either MT plus IVT or MT alone for LVO except for the procedural time. More trials are needed in this regard, and certain factors should be considered when comparing the two approaches.

Technical video: Onyx-18 embolization of spinal epidural arteriovenous Fistula using the scepter-Mini balloon catheter

Spinal arteriovenous fistulas (AVFs) account for approximately 70% of all vascular spinal malformations and commonly develop in the lateral epidural space at the epidural /radicular venous junction. The fistula is located close to the spinal nerve root where a radiculomeningeal artery shunts to a radicular vein. Increased venous pressure leads to decreased spinal venous drainage and venous congestion causing progressive myelopathy, bowel/bladder incontinence and erectile dysfunction. Treatment consists of surgical occlusion of the intradural vein, or endovascular embolization, which has a reported success rate of 25%-75%.1 Endovascular failure can occur with inadequate embolic penetration of the nidus and the proximal segment of the draining vein, or premature reflux of the liquid embolic agent.The use of a dual-lumen balloon microcatheter offers advantage in these cases given the ability to push liquid embolysate more distally during balloon inflation. The Scepter Mini is a new dimethyl-sulfoxide (DMSO)-compatible dual-lumen balloon microcatheter with a distal-tip outer diameter of 1.6 Fr and a nominal balloon diameter of 2.2 mm, facilitating atraumatic navigation and safer balloon inflation. Limited neurointerventional experience using the Scepter Mini in predominantly cerebrovascular cases has reported favorable navigability and flow arrest2, 3 Although Onyx is rarely used for spinal AVF embolization, success has been reported considering the well-known favorable experience in cerebral cases.1, 4, 5We present one of the first cases of Onyx embolization of a spinal dural AVF through a Scepter Mini in a patient with progressively worsening lower extremity sensorimotor dysfunction. Operators should be aware of radiculomedullary arteries arising at the same level or at adjacent levels to avoid unintentional Onyx migration during balloon inflation.

Artificial intelligence aneurysm measurement tool finds growth in all aneurysms that ruptured during conservative management

BACKGROUND

Cerebral aneurysm rupture is associated with high rates of morbidity and mortality. Detecting aneurysms at high risk of rupture is critical in management decision making. Rupture risk has traditionally been associated with size-measured as a maximum dimension. However, aneurysms are morphologically dynamic, a characteristic ignored by large prospective aneurysm risk studies. Manual measurement is challenging and fraught with error. We used an artificial intelligence (AI) measurement tool to study aneurysms that ruptured during conservative management to detect changes in size not appreciated by manual linear measurement.

METHODS

A single practice database with >5000 aneurysms was queried. Patients followed conservatively for an unruptured aneurysm were identified using appropriate diagnosis codes. This cohort was screened for subsequent rupture using procedure codes. Only patients with two vascular imaging studies before rupture were included.

RESULTS

Five patients met the criteria. All patients had aneurysm enlargement, two of which were not detected from manual linear measurements, including adjudication and analysis, during a multidisciplinary neurovascular conference in a high volume practice. Maximum dimension increased at a minimum of 1.8% (range 1.8-63.3%) from the first scan to the last, and aneurysm volume increased at a minimum of 5.9% (5.9-385.5%), highlighting the importance of volumetric measurement.

CONCLUSIONS

AI-enabled volumetric measurements are more sensitive to changes in size and detected enlargement in all aneurysms that ruptured during conservative management. This finding has major implications for clinical practice and methods used for interval aneurysm measurement in patients being conservatively followed.

Cerebral vasospasm following arteriovenous malformation rupture: a population-based cross-sectional study

OBJECTIVE

Studies examining the risk factors and clinical outcomes of arterial vasospasm secondary to cerebral arteriovenous malformation (cAVM) rupture are scarce in the literature. The authors used a population-based national registry to investigate this largely unexamined clinical entity.

METHODS

Admissions for adult patients with cAVM ruptures were identified in the National Inpatient Sample during the period from 2015 to 2019. Complex samples multivariable logistic regression and chi-square automatic interaction detection (CHAID) decision tree analyses were performed to identify significant associations between clinical covariates and the development of vasospasm, and a cAVM–vasospasm predictive model (cAVM-VPM) was generated based on the effect sizes of these parameters.

RESULTS

Among 7215 cAVM patients identified, 935 developed vasospasm, corresponding to an incidence rate of 13.0%; 110 of these patients (11.8%) subsequently progressed to delayed cerebral ischemia (DCI). Multivariable adjusted modeling identified the following baseline clinical covariates: decreasing age by decade (adjusted odds ratio [aOR] 0.87, 95% CI 0.83–0.92; p < 0.001), female sex (aOR 1.68, 95% CI 1.45–1.95; p < 0.001), admission Glasgow Coma Scale score < 9 (aOR 1.34, 95% CI 1.01–1.79; p = 0.045), intraventricular hemorrhage (aOR 1.87, 95% CI 1.17–2.98; p = 0.009), hypertension (aOR 1.77, 95% CI 1.50–2.08; p < 0.001), obesity (aOR 0.68, 95% CI 0.55–0.84; p < 0.001), congestive heart failure (aOR 1.34, 95% CI 1.01–1.78; p = 0.043), tobacco smoking (aOR 1.48, 95% CI 1.23–1.78; p < 0.019), and hospitalization events (leukocytosis [aOR 1.64, 95% CI 1.32–2.04; p < 0.001], hyponatremia [aOR 1.66, 95% CI 1.39–1.98; p < 0.001], and acute hypotension [aOR 1.67, 95% CI 1.31–2.11; p < 0.001]) independently associated with the development of vasospasm. Intraparenchymal and subarachnoid hemorrhage were not associated with the development of vasospasm following multivariable adjustment. Among significant associations, a CHAID decision tree algorithm identified age 50–59 years (parent node), hyponatremia, and leukocytosis as important determinants of vasospasm development. The cAVM-VPM achieved an area under the curve of 0.65 (sensitivity 0.70, specificity 0.53). Progression to DCI, but not vasospasm alone, was independently associated with in-hospital mortality (aOR 2.35, 95% CI 1.29–4.31; p = 0.016) and lower likelihood of routine discharge (aOR 0.62, 95% CI 0.41–0.96; p = 0.031).

CONCLUSIONS

This large-scale assessment of vasospasm in cAVM identifies common clinical risk factors and establishes progression to DCI as a predictor of poor neurological outcomes.

Neutrophil-Lymphocyte ratio is associated with poor clinical outcome after mechanical thrombectomy in stroke in patients with COVID-19

Background

The neutrophil–lymphocyte ratio (NLR) is emerging as an important biomarker of acute physiologic stress in a myriad of medical conditions, and is a confirmed poor prognostic indicator in COVID-19.

Objective

We sought to describe the role of NLR in predicting poor outcome in COVID-19 patients undergoing mechanical thrombectomy for acute ischemic stroke.

Methods

We analyzed NLR in COVID-19 patients with large vessel occlusion (LVO) strokes enrolled into an international 12-center retrospective study of laboratory-confirmed COVID-19, consecutively admitted between March 1, 2020 and May 1, 2020. Increased NLR was defined as ≥7.2. Logistic regression models were generated.

Results

Incidence of LVO stroke was 38/6698 (.57%). Mean age of patients was 62 years (range 27–87), and mortality rate was 30%. Age, sex, and ethnicity were not predictive of mortality. Elevated NLR and poor vessel recanalization (Thrombolysis in Cerebral Infarction (TICI) score of 1 or 2a) synergistically predicted poor outcome (likelihood ratio 11.65, p  =  .003). Patients with NLR > 7.2 were 6.8 times more likely to die (OR 6.8, CI95% 1.2–38.6, p  =  .03) and almost 8 times more likely to require prolonged invasive mechanical ventilation (OR 7.8, CI95% 1.2–52.4, p  =  .03). In a multivariate analysis, NLR > 7.2 predicted poor outcome even when controlling for the effect of low TICI score on poor outcome (NLR p  =  .043, TICI p  =  .070).

Conclusions

We show elevated NLR in LVO patients with COVID-19 portends significantly worse outcomes and increased mortality regardless of recanalization status. Severe neuro-inflammatory stress response related to COVID-19 may negate the potential benefits of successful thrombectomy.

The Use of a Pipeline Embolization Device for Treatment of a Ruptured Dissecting Middle Cerebral Artery M3/M4 Aneurysm: Challenges and Technical Considerations

Prompt, effective treatment is necessary following aneurysmal subarachnoid hemorrhage to prevent recurrent rupture, which is thought to double mortality. Atypical ruptured aneurysms, such as blister or dissecting pseudoaneurysms, or those that are unusually distal in the middle cerebral artery (MCA) are challenging to treat with either open or endovascular options, though the pipeline embolization device (PED) has shown promise in multiple case series. We present a case of a ruptured dissecting pseudoaneurysm in the distal MCA (distal M3/proximal M4) prefrontal division in an healthy young patient (<60 years) successfully treated with a PED. The PED was chosen both as the only vessel sparing option in the young patient as well as for its potential as a vessel sacrifice tool if the pseudoaneurysm was felt to be incompletely treated, which in this case was not necessary-though would have leveraged the thrombogenicity of the device as a therapeutic advantage.

Cardiac arrest in spontaneous subarachnoid hemorrhage and associated outcomes

OBJECTIVE

The authors sought to analyze a large, publicly available, nationwide hospital database to further elucidate the impact of cardiopulmonary arrest (CA) in association with subarachnoid hemorrhage (SAH) on short-term outcomes of mortality and discharge disposition.

METHODS

This retrospective cohort study was conducted by analyzing de-identified data from the National (Nationwide) Inpatient Sample (NIS). The publicly available NIS database represents a 20% stratified sample of all discharges and is powered to estimate 95% of all inpatient care delivered across hospitals in the US. A total of 170,869 patients were identified as having been hospitalized due to nontraumatic SAH from 2008 to 2014.

RESULTS

A total of 5415 patients (3.2%) were hospitalized with an admission diagnosis of CA in association with SAH. Independent risk factors for CA included a higher Charlson Comorbidity Index score, hospitalization in a small or nonteaching hospital, and a Medicaid or self-pay payor status. Compared with patients with SAH and not CA, patients with CA-SAH had a higher mean NIS Subarachnoid Severity Score (SSS) ± SD (1.67 ± 0.03 vs 1.13 ± 0.01, p < 0.0001) and a vastly higher mortality rate (82.1% vs 18.4%, p < 0.0001). In a multivariable model, age, NIS-SSS, and CA all remained significant independent predictors of mortality. Approximately 18% of patients with CA-SAH survived and were discharged to a rehabilitation facility or home with health services, outcomes that were most predicted by chronic disease processes and large teaching hospital status.

CONCLUSIONS

In the largest study of its kind, CA at onset was found to complicate roughly 3% of spontaneous SAH cases and was associated with extremely high mortality. Despite this, survival can still be expected in approximately 18% of patients.

Neurocritical care management of poor-grade subarachnoid hemorrhage: Unjustified nihilism to reasonable optimism

BACKGROUND AND PURPOSE

Historically, overall outcomes for patients with high-grade subarachnoid hemorrhage (SAH) have been poor. Generally, between physicians, either reluctance to treat, or selectivity in treating such patients has been the paradigm. Recent studies have shown that early and aggressive care leads to significant improvement in survival rates and favorable outcomes of grade V SAH patients. With advancements in both neurocritical care and end-of-life care, non-treatment or selective treatment of grade V SAH patients is rarely justified. Current paradigm shifts towards early and aggressive care in such cases may lead to improved outcomes for many more patients.

MATERIALS AND METHODS

We performed a detailed review of the current literature regarding neurointensive management strategies in high-grade SAH, discussing multiple aspects. We discussed the neurointensive care management protocols for grade V SAH patients.

RESULTS

Acutely, intracranial pressure control is of utmost importance with external ventricular drain placement, sedation, optimization of cerebral perfusion pressure, osmotherapy and hyperventilation, as well as cardiopulmonary support through management of hypotension and hypertension.

CONCLUSIONS

Advancements of care in SAH patients make it unethical to deny treatment to poor Hunt and Hess grade patients. Early and aggressive treatment results in a significant improvement in survival rate and favorable outcome in such patients.

Relation between brain natriuretic peptide and delayed cerebral ischemia in patients with aneurysmalsubarachnoid hemorrhage

BACKGROUND

Brain natriuretic peptide (BNP), often used to evaluate degree of heart failure, has been implicated in fluid dysregulation and inflammation in critically-ill patients. Twenty to 30% of patients with aneurysmal subarachnoid hemorrhage (aSAH) will develop some degree of neurogenic stress cardiomyopathy (NSC) and in turn elevation of BNP levels. We sought to explore the association between BNP levels and development of delayed cerebral ischemia (DCI) in patients with aSAH.

METHODS

We retrospectively evaluated the records of 149 patients admitted to the Neurological Intensive Care Unit between 2006 and 2015 and enrolled in an existing prospectively maintained aSAH database. Demographic data, treatment and outcomes, and BNP levels at admission and throughout the hospital admission were noted.

RESULTS

Of the 149 patients included in the analysis, 79 developed DCI during their hospital course. We found a statistically significant association between DCI and the highest recorded BNP (OR 1.001, 95% CI-1.001-1.002, p = 0.002). The ROC curve analysis for DCI based on BNP showed that the highest BNP level during hospital admission (AUC 0.78) was the strongest predictor of DCI compared to the change in BNP over time (AUC 0.776) or the admission BNP (AUC 0.632).

CONCLUSION

Our study shows that DCI is associated not only with higher baseline BNP values (admission BNP), but also with the highest BNP level attained during the hospital course and the rapidity of change or increase in BNP over time. Prospective studies are needed to evaluate whether routine measurement of BNP may help identify SAH patients at high risk of DCI.

Spontaneous Regression of Cerebral Arteriovenous Malformation Following Onyx Embolization

Little is known about the natural history of arteriovenous malformations (AVM) and less is known about their potential for spontaneous regression. The advent of endovascular treatment for embolization or pre-surgical embolization of cerebral arteriovenous malformations (cAVM) has seen several reports of spontaneous regression of partial embolization of cAVMs surface in the literature.

A 66-year-old patient had an initial diagnostic cerebral angiogram revealing a left frontoparietal region Spetzler-Martin (SM) grading 4 cAVM. The patient underwent three stages of embolization over eight months leading to a 90% reduction in nidal volume, before being lost to follow up for six years. A six-vessel diagnostic cerebral angiogram was performed at that time to assess for any interval changes and surprisingly, the previously visualized left frontoparietal AVM had regressed. There was evidence of prior onyx embolization with no residual filling or recurrence.

Spontaneous regression after partial embolization may be under-reported or the natural history is simply unable to temporally unfold because the typical treatment course results in surgery following partial embolization. Given the potential to forgo the risks of an open procedure, we believe this topic deserves further attention.

Impact of pre-ictal antiplatelet therapy use in aneurysmal subarachnoid hemorrhage

OBJECTIVE

There is limited evidence on the use of antiplatelet therapy (APT) to reduce the risk and morbidity of cerebral aneurysmal rupture. This analysis retrospectively assessed APT use in patients presenting to our institution with aneurysmal subarachnoid hemorrhage (aSAH).

METHODS

We evaluated the records of 186 patients over 7 years of retrospective data from our tertiary care center and an existing database of patients with aSAH. A total of 18 cases with patients on APT and 168 patients not on APT (controls) were identified. Primary outcomes measured were clinical grade (Hunt and Hess score), radiographic grade (Fisher score), and presence of delayed cerebral ischemia (DCI). Secondary outcomes were modified Rankin score at discharge and at 3 months. DCI from cerebral vasospasm was defined as the occurrence of focal neurological impairment or a decrease in at least 2 points on the Glasgow Coma Scale. Logistic regression models were generated.

RESULTS

We found that APT use did not appear to lead to statistically significant differences in initial presentation, including Hunt-Hess score and Fisher grade (2.91 vs 3.06, p = 0.66, and 3.23 vs 3.22, p = 0.96 respectively). In addition, APT use was not associated with increased rates of delayed cerebral ischemia (DCI) (OR 0.27 p = 0.12). Our analysis showed that increased Hunt Hess score and the presence of DCI are both associated with increased mRS at 90 days (OR 2.32 p < 0.001; OR 2.91 p = 0.002).

CONCLUSION

The patients in this retrospective observational study did not demonstrate worse outcomes from their aSAH despite APT therapy. Larger prospective studies should be performed to see if this relationship holds and if decreased rates of DCI can be observed.

Adjustment of Malpositioned Woven EndoBridge Device Using Gooseneck Snare: Complication Management Technique

The Woven EndoBridge (WEB) is an intrasaccular flow-disrupting device for the treatment of wide-necked saccular cerebral aneurysms. As with any neuroendovascular device, complications in the form of malpositioning and migration must be managed quickly and safely. Few studies have reported complication management techniques in instances of dislocated or migrated WEB devices. We retrospectively describe a case of a malpositioned WEB device that was successfully adjusted with the use of a gooseneck snare. Multiple other intra-procedural bailout strategies for management of WEB malposition and migration were considered, and are herein discussed. Operators should be aware of the causes of WEB malposition and a variety of bailout strategies.

Thrombectomy in special populations: report of the Society of NeuroInterventional Surgery Standards and Guidelines Committee

BACKGROUND

The purpose of this guideline is to summarize the data available for performing mechanical thrombectomy (MT) for emergent large vessel occlusion (ELVO) stroke in special populations not typically included in large randomized controlled clinical trials, including children, the elderly, pregnant women, patients who have recently undergone surgery, and patients with thrombocytopenia, collagen vascular disorders, and endocarditis.

METHODS

We performed a literature review for studies examining the indications, efficacy, and outcomes for patients undergoing MT for ischemic stroke aged <18 years and >80 years, pregnant patients, patients who have recently undergone surgery, and those with thrombocytopenia, collagen vascular diseases, or endocarditis. We graded the quality of the evidence.

RESULTS

MT can be effective for the treatment of ELVO in ischemic stroke for patients over age 80 years and under age 18 years, thrombocytopenic patients, pregnant patients, and patients with endocarditis. While outcomes are worse compared to younger patients and those with normal platelet counts (respectively), there is still a benefit in the elderly (in both mRS and mortality). Data are very limited for patients with collagen vascular diseases; although diagnostic cerebral angiography carries increased risks, MT may be appropriate in carefully selected patients in whom untreated ELVO would likely result in disabling or fatal outcome.

Cerebral Venous Thrombosis in COVID-19: A New York Metropolitan Cohort Study

BACKGROUND AND PURPOSE

Severe Acute Respiratory Syndrome coronavirus 2 (SARS-CoV-2) infection is associated with hypercoagulability. We sought to evaluate the demographic and clinical characteristics of cerebral venous thrombosis among patients hospitalized for coronavirus disease 2019 (COVID-19) at 6 tertiary care centers in the New York City metropolitan area.

MATERIALS AND METHODS

We conducted a retrospective multicenter cohort study of 13,500 consecutive patients with COVID-19 who were hospitalized between March 1 and May 30, 2020.

RESULTS

Of 13,500 patients with COVID-19, twelve had imaging-proved cerebral venous thrombosis with an incidence of 8.8 per 10,000 during 3 months, which is considerably higher than the reported incidence of cerebral venous thrombosis in the general population of 5 per million annually. There was a male preponderance (8 men, 4 women) and an average age of 49 years (95% CI, 36-62 years; range, 17-95 years). Only 1 patient (8%) had a history of thromboembolic disease. Neurologic symptoms secondary to cerebral venous thrombosis occurred within 24 hours of the onset of the respiratory and constitutional symptoms in 58% of cases, and 75% had venous infarction, hemorrhage, or both on brain imaging. Management consisted of anticoagulation, endovascular thrombectomy, and surgical hematoma evacuation. The mortality rate was 25%.

CONCLUSIONS

Early evidence suggests a higher-than-expected frequency of cerebral venous thrombosis among patients hospitalized for COVID-19. Cerebral venous thrombosis should be included in the differential diagnosis of neurologic syndromes associated with SARS-CoV-2 infection.

Middle Meningeal Artery Embolization Using Combined Particle Embolization and n-BCA with the Dextrose 5% in Water Push Technique for Chronic Subdural Hematomas: A Prospective Safety and Feasibility Study

BACKGROUND AND PURPOSE

Embolization of the middle meningeal artery for treatment of refractory or recurrent chronic subdural hematomas has gained momentum during the past few years. Little has been reported on the use of the n-BCA liquid embolic system for middle meningeal artery embolization. We present the technical feasibility of using diluted n-BCA for middle meningeal artery embolization.

MATERIALS AND METHODS

We sought to examine the safety and technical feasibility of the diluted n-BCA liquid embolic system for middle meningeal artery embolization. Patients with chronic refractory or recurrent subdural hematomas were prospectively enrolled from September 2019 to June 2020. The primary outcome was the safety and technical feasibility of the use of diluted n-BCA for embolization of the middle meningeal artery. The secondary end point was the efficacy in reducing hematoma volume.

RESULTS

A total of 16 patients were prospectively enrolled. Concomitant burr-hole craniotomies were performed in 12 of the 16 patients. Two patients required an operation following middle meningeal artery embolization for persistent symptoms. The primary end point was met in 100% of cases in which there were no intra- or postprocedural complications. Distal penetration of the middle meningeal artery branches was achieved in all the enrolled cases. A 7-day post-middle meningeal artery embolization follow-up head CT demonstrated improvement (>50% reduction in subdural hematoma volume) in 9/15 (60%) patients, with 6/15 (40%) showing an unchanged or stable subdural hematoma. At day 21, available CT scans demonstrated substantial further improvement (>75% reduction in subdural hematoma volume).

CONCLUSIONS

Embolization of the middle meningeal artery using diluted n-BCA and ethiodized oil (1:6) is safe and feasible from a technical standpoint. The use of a dextrose 5% bolus improves distal penetration of the glue.

Patient Characteristics and Outcomes Associated with Decline in Stroke Volumes During the Early COVID-19 Pandemic

Background and Purpose

Delayed evaluation of stroke may contribute to COVID-19 pandemic-related morbidity and mortality. This study evaluated patient characteristics, process measures and outcomes associated with the decline in stroke presentation during the early pandemic.

Methods

Volumes of stroke presentations, intravenous thrombolytic administrations, and mechanical thrombectomies from 52 hospitals from January 1-June 30, 2020 were analyzed with piecewise linear regression and linear spline models. Univariate analysis compared pandemic (case) and pre-pandemic (control) groups defined in relation to the nadir of daily strokes during the study period. Significantly different patient characteristics were further evaluated with logistic regression, and significantly different process measures and outcomes were re-analyzed after propensity score matching.

Results

Analysis of 7,389 patients found daily stroke volumes decreased 0.91/day from March 12–26 (p < 0.0001), reaching a nadir 35.0% less than expected, and increased 0.15 strokes/day from March 27-June 23, 2020 (p < 0.0001). Intravenous thrombolytic administrations decreased 3.3/week from February 19-March 31 (p = 0.0023), reaching a nadir 33.4% less than expected, and increased 1.4 administrations/week from April 1-June 23 (p < 0.0001). Mechanical thrombectomy volumes decreased by 1.5/week from February 19-March 31, 2020 (p = 0.0039), reaching a nadir 11.3% less than expected. The pandemic group was more likely to ambulate independently at baseline (p = 0.02, OR = 1.60, 95% CI = 1.08–2.42), and less likely to present with mild stroke symptoms (NIH Stroke Scale ≤ 5; p = 0.04, OR = 1.01, 95% CI = 1.00–1.02). Process measures and outcomes of each group did not differ, including door-to-needle time, door-to-puncture time, and successful mechanical thrombectomy rate.

Conclusion

Stroke presentations and acute interventions decreased during the early COVID-19 pandemic, at least in part due to patients with lower baseline functional status and milder symptoms not seeking medical care. Public health messaging and initiatives should target these populations.

The Dilator-Dotter Technique: A Modified Method of Rapid Internal Carotid Artery Revascularization in Acute Ischemic Stroke

BACKGROUND AND PURPOSE

Acute ischemic stroke due to tandem occlusive lesions involves high-grade ICA stenosis or occlusion with a distal intracranial occlusion. Several approaches and devices exist in the treatment of tandem occlusions; however, a consensus on the optimal technique does not exist. The Dotter technique is a method of catheter-based angioplasty to recanalize cervical ICA occlusions. We present a modified dilator-Dotter technique, which involves a polyethylene, tapered inner dilator to initially cross the occlusion, followed by guide catheterization and subsequent intracranial thrombectomy. The purpose of this study was to examine the safety and efficacy of this dilator-Dotter technique.

MATERIALS AND METHODS

We performed a retrospective review of patients with acute stroke due to tandem ICA intracranial occlusions, treated with our dilator-Dotter technique and thrombectomy between June 2018 and December 2019. We examined clinical, radiographic, and procedural data, as well as complications and outcomes.

RESULTS

Thirty-two patients were included. In 100% of cases, the dilator-Dotter technique resulted in ICA recanalization allowing successful thrombectomy. TICI 2b-3 revascularization was obtained in 31 patients (96%), within an average time of 25 minutes. The average preprocedural ICA stenosis was 98%, including 23 patients (72%) with complete occlusion. Following the dilator-Dotter technique, average ICA stenosis improved to 59%. There were no instances of death, iatrogenic dissection, emboli to new territory, or symptomatic intracranial hemorrhage.

CONCLUSIONS

The dilator-Dotter technique may be a safe and effective modification of the traditional Dotter technique in allowing rapid ICA recanalization in cases of acute ischemic stroke due to tandem occlusions.

Flow diversion treatment of anterior communicating artery region aneurysms

BACKGROUND AND PURPOSE

Reports on flow diversion treatment of aneurysms beyond the Circle of Willis are limited, with few series dedicated to anterior communicating artery region aneurysms. The purpose of this study is to evaluate the safety and effectiveness of the pipeline embolization device in the treatment of anterior communicating artery region aneurysms.

MATERIALS AND METHODS

The neuro-interventional database of a single institution was retrospectively reviewed for anterior communicating artery aneurysms treated with the pipeline embolization device between November 2016 and December 2018. Data on clinical presentation, aneurysm location, type, vessel size, procedural complications, clinical and imaging follow-up were analyzed.

RESULTS

Ten patients with 11 anterior communicating artery aneurysms were included. Procedural success was achieved in 9/10 patients (90%). Flow diversion with the pipeline embolization device yielded occlusion in 100% of patients at 6.5 months. Symptomatic ischemic complications occurred in 2/10 patients (20%); only one of who had permanent symptoms. Hemorrhagic groin complications were encountered in 2/10 patients (20%). There were no deaths and no cerebral hemorrhagic complications.

CONCLUSIONS

Flow diversion therapy may provide a feasible solution for anterior communicating artery region aneurysms that are not amenable to traditional surgical or endovascular modalities.

Neuroendovascular Cerebral Sinus Stenting in Idiopathic Intracranial Hypertension

Idiopathic intracranial hypertension (IIH) is a rare, ill-understood disease of significant morbidity. Because the pathophysiology is poorly understood, treatment protocols are not uniform and are directed towards alleviating the most common symptoms: headache and visual loss. In this review, we analyze 25 case series, all of which included IIH patients (n = 408) who were treated with placement of a venous sinus stent. Among 342 patients who had headache, 240 patients (70.2%) had improvement or resolution of headache after the stent insertion. Of the 217 patients documented to have visual problems, visual acuity was improved or stabilized in 161 patients (74.2%). Of the 304 patients with papilledema, 257 showed resolution or improved (84.5%). Of the 124 patients who presented with pulsatile tinnitus, it was resolved in 110 patients (88.7%) after stent placement. Endovascular management of dural sinus stenosis is therefore clinically efficacious in patients with IIH who have failed medical and surgical therapy.

Admission neutrophil–lymphocyte ratio predicts delayed cerebral ischemia following aneurysmal subarachnoid hemorrhage

Background

Delayed cerebral ischemia (DCI) following aneurysmal subarachnoid hemorrhage (aSAH) has a multifactorial pathophysiology, with immune dysregulation being an important component. The neutrophil–lymphocyte ratio (NLR) is an established prognostic marker in patients with cancer, cardiac disease, and sepsis.

Objective

To determine whether there is a relationship between NLR and DCI in patients with aSAH.

Methods

We evaluated 1067 patients with aSAH between 2006 and 2015 enrolled in a single-center, prospective, observational cohort study. Admission white blood cell differentials (NLR) were analyzed using a cut-off point of ≥5.9. DCI from cerebral vasospasm was defined as the occurrence of focal neurological impairment, or a decrease in at least two points on the Glasgow Coma Scale, which was not apparent immediately after aneurysm occlusion, and could not be attributed to other causes. Cerebral infarct was defined as a new infarct on CT that was not visible on the admission or immediate postoperative scan, when the cause was thought to be vasospasm by the research team. Logistic regression models were generated.

Results

We found that 768 (72%) patients had an admission NLR ≥5.9. In a multivariable model, elevated NLR was associated with poor admission Hunt-Hess grade (OR=1.6, 95% CI 1.2 to 2.6, p=0.005), Caucasian ethnicity (OR=2.6, 95% CI 1.9 to 3.7, p<0.001), anterior aneurysm location (OR=1.7, 95% CI 1.2 to 2.4, p=0.004), loss of consciousness at ictus (OR=1.4, 95% CI 1.0 to 2.0, p=0.055), and thick SAH (modified Fisher grade ≥3) (OR=1.8, 95% CI 1.3 to 2.4, p<0.001). Admission NLR predicted development of delayed cerebral ischemia (DCI) (OR=1.7; 95% CI 1.1 to 2.5, p=0.008) after controlling for known predictors such as age, poor admission clinical grade, thick SAH blood, and elevated admission mean arterial pressure.

Conclusions

This study provides further evidence of the association between inflammation and DCI. Admission NLR is a readily available and convenient biomarker that may be a clinically useful tool for prognostication when evaluating aSAH.

Mandatory Neuroendovascular Evolution: Meeting the New Demands

Background

Traditionally, patients undergoing acute ischemic strokes were candidates for mechanical thrombectomy if they were within the 6-h window from onset of symptoms. This timeframe would exclude many patient populations, such as wake-up strokes. However, the most recent clinical trials, DAWN and DEFUSE3, have expanded the window of endovascular treatment for acute ischemic stroke patients to within 24 h from symptom onset. This expanded window increases the number of potential candidates for endovascular intervention for emergent large vessel occlusions and raises the question of how to efficiently screen and triage this increase of patients.

Summary

Abbreviated pre-hospital stroke scales can be used to guide EMS personnel in quickly deciding if a patient is undergoing a stroke. Telestroke networks connect remote hospitals to stroke specialists to improve the transportation time of the patient to a comprehensive stroke center for the appropriate level of care. Mobile stroke units, mobile interventional units, and helistroke reverse the traditional hub-and-spoke model by bringing imaging, tPA, and expertise to the patient. Smartphone applications and social media aid in educating patients and the public regarding acute and long-term stroke care.

Key Messages

The DAWN and DEFUSE3 trials have expanded the treatment window for certain acute ischemic stroke patients with mechanical thrombectomy and subsequently have increased the number of potential candidates for endovascular intervention. This expansion brings patient screening and triaging to greater importance, as reducing the time from symptom onset to decision-to-treat and groin puncture can better stroke patient outcomes. Several strategies have been employed to address this issue by reducing the time of symptom onset to decision-to-treat time.

Management Strategies for Intracranial Pressure Crises in Subarachnoid Hemorrhage

Objectives: Standard management strategies for lowering intracranial pressure (ICP) in traumatic brain injury has been well-studied, but the use of lesser known interventions for ICP in subarachnoid hemorrhage (SAH) remains elusive. Searches were performed in PubMed and EBSCO Host to identify best available evidence for evaluation and management of medically refractory ICP in SAH. The role of standard management strategies such as head elevation, hyperventilation, mannitol and hypertonic saline as well as lesser known management such as sodium bicarbonate, indomethacin, tromethamine, decompressive craniectomy, decompressive laparotomy, hypothermia, and barbiturate coma are reviewed. We also included dose concentrations, dose frequency, infusion volume, and infusion rate for these lesser known strategies. Nonetheless, there is still a gap in the evidence to recommend optimal dosing, timing and its role in the improvement of outcomes but early diagnosis and appropriate management reduce adverse outcomes.

Isolated Intraventricular Hemorrhage Associated with Cerebral Vasospasm and Delayed Cerebral Ischemia following Arteriovenous Malformation Rupture

Background

Although it is well characterized in aneurysmal subarachnoid hemorrhage, vasospasm is exceedingly rare following cerebral arteriovenous malformation (AVM) rupture. Subsequently, this complication is poorly characterized with regard to delayed cerebral ischemia (DCI). We review cases of ruptured AVM to assess the frequency and severity of vasospasm on cerebral angiography, and DCI.

Summary

We reviewed our institutional database of acute intracranial hemorrhages between 2005 and 2014. We identified patients with cerebral AVM rupture and evidence of vasospasm, which was confirmed with digital subtraction angiography (DSA). Cerebral angiograms were evaluated by 2 blinded neurointerventionalists for vasospasm. Statistical analyses were conducted on the angiographic results and variables of interest to determine predictors and associations of vasospasm and DCI. Thirty-six patients with acute intracranial hemorrhage due to ruptured cerebral AVM subsequently underwent cerebral angiography. The interrater reliability for vasospasm was 0.81. The incidence of vasospasm was 13.9% and the incidence of subsequent DCI was 11.1%. A significant relationship existed between isolated intraventricular hemorrhage and vasospasm (p = 0.001) and subsequent DCI (p = 0.006). Radiographic vasospasm was associated with DCI in 80% of the patients (p < 0.0001). No statistical significance existed between subarachnoid hemorrhage and the development of vasospasm or DCI (p = 1.000 and p = 0.626, respectively). All differences were significant at a 99% level of significance.

Key Message

In cases of ruptured AVM, isolated intraventricular hemorrhage appears to be an independent risk factor for vasospasm and DCI. Vasospasm must be considered during late neurological deterioration following AVM hemorrhage, especially in the setting of isolated intraventricular hemorrhage.

Acute Ischemic Stroke due to Common Carotid Ostial Disease with Tandem Intracranial Occlusions Treated with Thrombectomy and Staged Retrograde Stenting

Background

Acute ischemic stroke due to tandem occlusive lesions of the anterior circulation involves an intracranial large vessel occlusion as well as a concurrent occlusion or high-grade stenosis of the proximal carotid system. The vast majority of proximal lesions in tandem occlusive cases involve the extracranial internal carotid artery, although the lesion can theoretically exist anywhere along the carotid artery pathway, including the common carotid ostium.

Summary

To the best of our knowledge, only 1 report describes common carotid artery ostial lesions in the setting of acute ischemic stroke due to tandem occlusions, in which the authors describe an anterograde treatment paradigm. We present the first 2 cases of acute ischemic stroke secondary to common carotid ostial disease with tandem intracranial occlusion, treated with intracranial thrombectomy followed by subsequent staged balloon-mounted stenting of the common carotid ostium. We review the pathophysiology of tandem occlusions, the controversy surrounding treatment techniques, and various approaches used in the treatment of ostial occlusive lesions.

Key Message

In certain situations where acute carotid stenting is not safe or technically possible, immediate intracranial thrombectomy with a subsequent staged balloon-mounted stenting of the ostial lesion may be a reasonable and safe option.

Bailout Strategies and Complications Associated with the Use of Flow-Diverting Stents for Treating Intracranial Aneurysms

Background

Flow-diverting stents (FDS) have revolutionized the endovascular management of unruptured, complex, wide-necked, and giant aneurysms. There is no consensus on management of complications associated with the placement of these devices. This review focuses on the management of complications of FDS for the treatment of intracranial aneurysms.

Summary

We performed a systematic, qualitative review using electronic databases MEDLINE and Google Scholar. Complications of FDS placement generally occur during the perioperative period.

Key Message

Complications associated with FDS may be divided into periprocedural complications, immediate postprocedural complications, and delayed complications. We sought to review these complications and novel management strategies that have been reported in the literature.

Endovascular intervention of acute ischemic stroke due to occlusion of fetal posterior cerebral artery

A fetal posterior cerebral artery (FPCA) is an anatomic variant in which the posterior cerebral artery is an embryological derivative of the internal carotid artery. Although most cases of ischemic strokes in patients with FPCAs involve embolic infarcts, emergent large vessel occlusion of a FPCA is extremely rare. We present two cases of successful endovascular intervention for emergent occlusion of a FPCA, one of which is only the second reported case of a mechanical thrombectomy of a FPCA. We review the embryology of FPCA, the controversy regarding its association with cerebral infarcts, and various approaches used in the treatment of such occlusive lesions.

Low Glasgow Coma Score in Traumatic Intracranial Hemorrhage Predicts Development of Cerebral Vasospasm

BACKGROUND

The exact mechanism, incidence, and risk factors for cerebral vasospasm after traumatic intracranial hemorrhage (ICH) continue to be poorly characterized. The incidence of post-traumatic vasospasm (PTV) varies depending on the detection modality.

OBJECTIVE

We aimed to shed light on the predictors, associations, and true incidence of cerebral vasospasm after traumatic ICH using digital subtraction angiography (DSA) as the gold standard.

METHODS

We examined a prospectively maintained database of traumatic brain injury (TBI) patients to identify patients with ICH secondary to TBI enrolled between 2002 and 2015 at our trauma center. Patients with TBI-associated ICH and evidence of elevated velocities on transcranial Doppler and computed tomography angiograms, confirmed with DSA were included. The diagnostic cerebral angiograms were evaluated by 2 blinded neurointerventionalists for cerebral vasospasm. Statistical analyses were conducted to determine predictors of PTV.

RESULTS

Twenty patients with ICH secondary to TBI and evidence of vasospasm underwent DSAs. Seven patients (7/20; 35%) with traumatic ICH developed cerebral vasospasm and of those, 1 developed delayed cerebral ischemia (1/7; 14%). Of these 7 patients, 6 presented with subarachnoid hemorrhage (6/7; 85%). Vasospasm was substantially more common in patients with a Glasgow Coma Scale <9 (P = 0.017) than in all other groups.

CONCLUSIONS

PTV as demonstrated by DCA may be more common than previously reported. Patients who exhibit PTV were more likely to have a Glasgow Coma Scale <9. This subgroup of patients may benefit from more systematic screening for the development of PTV, and earlier monitoring for signs of delayed cerebral ischemia.

Endovascular Retrieval of Migrated Coil within the Distal Middle Cerebral Artery Using Stentriever Device

BACKGROUND

Displacement of endovascular coils during endovascular embolization of an intracranial aneurysm is a potentially life-threatening complication. Several methods for coil retrieval have been described, including the use of microsnares and microforceps retrieval devices. With the recent surge of stentriever implementation in the treatment of ischemic stroke, some operators are now using such devices in the retrieval of migrated coils. We present a case of a balloon-assisted coil embolization of a communicating segment internal carotid artery aneurysm, complicated by coil migration far distally into the middle cerebral artery, which was retrieved successfully with a stentriever. To the best of our knowledge, this is the furthest migration of a coil to be successfully retrieved with a stentriever. We review conservative and invasive management of displaced coils and the technical advantages of stentrievers over retrieval devices.

METHODS

The patient's medical records were retrospectively reviewed, including clinical and radiographic information. This study received institutional review board approval.

RESULTS

The patient was treated with balloon-assisted coil embolization of the internal carotid artery aneurysm. The migrated coil was retrieved successfully using a novel application of a stentriever.

CONCLUSIONS

In certain situations, a stentriever does not mandate complete ensnaring of the target to be retrieved and thus need not always be deployed distal to a migrated coil mass to be successful. Due to the mechanical advantage of strut-engagement, stentrievers can afford to be positioned in relatively suboptimal positions, and this is especially useful in cases involving tortuous and small distal vessels (<2 mm diameter).

Severity of cerebral vasospasm associated with development of collaterals following aneurysmal subarachnoid hemorrhage

Introduction

Cerebral collateral circulation has been studied extensively in ischemic stroke where it has been shown to be a predictor of reperfusion, final infarct size, and outcome. Little is known about the significance of the collaterals in the setting of aneurysmal subarachnoid hemorrhage (aSAH). We sought to evaluate the effect of cerebral vasospasm on the development of cerebral collaterals following aneurysmal subarachnoid hemorrhage and the effects of the latter on delayed cerebral ischemia (DCI).

Methods

We retrospectively evaluated 64 aSAH patients with evidence of DCI between day 5 and 7, enrolled in a prospectively maintained observational cohort study. Angiograms were evaluated by four blinded neurointerventionalists. We compared good collateral grades to poor collateral grades, additionally we compared enrolled individuals with any collaterals versus patients who had no collaterals.

Results

Inter-rater reliability for collateral grades was substantial (weighted kappa 0.632). Mild vasospasm was more frequent in patients with poor collateral grades compared with patients with good collateral grades (32% vs 4% P=0.012). There was no difference between the collateral groups with regards to DCI, functional, or cognitive outcome. Patients adjudicated to have any collaterals were more likely to have severe vasospasm (62% vs 33% P=0.023) and less likely to have mild vasospasm (37% vs 9% P=0.007). In a multivariable model, vasospasm severity remained associated with collateral status, while aneurysm location was not.

Conclusions

The severity of vasospasm following aSAH was associated with the development of collaterals. There was no difference between collateral grades with regards to DCI or outcome.

Novel minimally invasive multi-modality monitoring modalities in neurocritical care

Elevated intracranial pressure (ICP) following brain injury contributes to poor outcomes for patients, primarily by reducing the caliber of cerebral vasculature, and thereby reducing cerebral blood flow. Careful monitoring of ICP is critical in these patients in order to determine prognosis, implement treatment when ICP becomes elevated, and to judge responsiveness to treatment. Currently, the gold standard for monitoring is invasive pressure transducers, usually an intraventricular monitor, which presents significant risk of infection and hemorrhage. These risks made discovering non-invasive methods for monitoring ICP and cerebral perfusion a priority for researchers. Herein we sought to review recent publications on novel minimally invasive multi-modality monitoring techniques that provide surrogate data on ICP, cerebral oxygenation, metabolism and blood flow. While limitations in various forms preclude them from supplanting the use of invasive monitors, these modalities represent useful screening tools within our armamentarium that may be invaluable when the risks of invasive monitoring outweigh the associated benefits.

Rescue Therapy for Procedural Complications Associated With Deployment of Flow-Diverting Devices in Cerebral Aneurysms

Flow diverting devices (FDDs) have revolutionized the treatment of morphologically complex intracranial aneurysms such as wide-necked, giant, or fusiform aneurysms. Although FDDs are extremely effective, they carry a small yet significant risk of intraprocedural complications. As the implementation of these devices increases, the ability to predict and rapidly treat complications, especially those that are iatrogenic or intraprocedural in nature, is becoming increasingly more necessary.

Our objective in this paper is to provide a descriptive summary of the various types of intraprocedural complications that may occur during FDDs deployment and how they may best be treated. A systematic and qualitative review of the literature was conducted using electronic databases MEDLINE and Google Scholar. Searches consisted of Boolean operators “AND” and “OR” for the following terms in different combinations: “aneurysm,” “endovascular,” “flow diverter,” “intracranial,” and “pipeline.”

A total of 94 papers were included in our analysis; approximately 87 of these papers dealt with periprocedural endovascular (mainly related to FDDs) complications and their treatment; 7 studies concerned background material. The main categories of periprocedural complications encountered during deployment of FDDs are failure of occlusion, parent vessel injury and/or rupture, spontaneous intraparenchymal hemorrhage, migration or malposition of the FDDs, thromboembolic or ischemic events, and side branch occlusion

Periprocedural complications occur mainly due to thromboembolic events or mechanical issues related to device deployment and placement. With increasing use and expanding versatility of FDDs, the understanding of these complications is vital in order to effectively manage such situations in a timely manner.

Isolated intraventricular hemorrhage secondary to dural arteriovenous fistula

Isolated intraventricular hemorrhage due to dural arteriovenous fistula (dAVF) is extremely rare and has been reported only a few times in the literature. The pathophysiological cause of isolated intraventricular hemorrhage in these cases was hypothetically attributed to retrograde venous flow into subependymal vessels, although none of these cases demonstrated radiographic evidence of such reflux. We present the first case of a dAVF with radiographic evidence of severe cortical venous reflux into the subependymal venous network causing isolated intraventricular hemorrhage, thus lending proof for the underlying pathophysiology. Furthermore, ours is the first case of dAVF with isolated intraventricular hemorrhage that was successfully treated using multimodality transvenous and transarterial embolization techniques. In cases of high-grade dAVF, multimodality treatment may offer the greatest chance for success, and should be strongly considered for management.

Isolated intraventricular hemorrhage secondary to dural arteriovenous fistula

Isolated intraventricular hemorrhage due to dural arteriovenous fistula (dAVF) is extremely rare and has been reported only a few times in the literature. The pathophysiological cause of isolated intraventricular hemorrhage in these cases was hypothetically attributed to retrograde venous flow into subependymal vessels, although none of these cases demonstrated radiographic evidence of such reflux. We present the first case of a dAVF with radiographic evidence of severe cortical venous reflux into the subependymal venous network causing isolated intraventricular hemorrhage, thus lending proof for the underlying pathophysiology. Furthermore, ours is the first case of dAVF with isolated intraventricular hemorrhage that was successfully treated using multimodality transvenous and transarterial embolization techniques. In cases of high-grade dAVF, multimodality treatment may offer the greatest chance for success, and should be strongly considered for management.

Clinical and Radiographic Predictors of Intracerebral Hemorrhage Outcome

BACKGROUND

Intracerebral hemorrhage (ICH) represents 10-15% of all stroke cases in the US annually. Fewer than 40% of these patients ever reach long-term functional independence, and mortality rate is roughly 40% at 1 month. Due to the high morbidity and mortality rates after ICH, early detection of high-risk patients would be beneficial in directing the management course and goals of care. This review aims to discuss relevant clinical and radiographic characteristics that can serve as predictors of poor prognosis and examine their efficacy in predicting patient outcomes after ICH.

SUMMARY

A literature review was conducted on various clinical and radiographic factors. They were examined for their predictive value in relation to ICH outcome. Studies that focused on each of these factors were included, and their results analyzed for trends with regard to incidence, patient outcome, and mortality rate.

KEY MESSAGE

In this review, we examined clinical and radiographic characteristics that have been found to be significantly associated to a varying degree with poor outcome. Clinical and radiographic predictors of poor patient outcome are invaluable when it comes to identifying high-risk patients and triaging accordingly as well as guiding decision-making.

Mechanical Thrombectomy of Acute Middle Cerebral Artery Occlusion Using Trans-Anterior Communicating Artery Approach

BACKGROUND

A cross-circulation technique involves gaining access to a cerebral vessel through a patent anterior or posterior communicating artery. This technique may be used in patients with emergent large-vessel occlusions and an unfavorable direct route to the occlusion. While few previous reports have demonstrated a successful cross-circulation technique for treatment of emergent large-vessel occlusions, we present the first 2 cases of transanterior communicating artery stent retriever thrombectomy.

CASE DESCRIPTION

Case #1: A 64-year-old female presented with acute right middle cerebral artery (MCA) occlusion. She demonstrated a "triple-tandem" brachiocephalic-internal carotid artery-middle cerebral artery occlusion, thus precluding direct access to the right MCA. Successful stent retriever mechanical thrombectomy was performed across the anterior communicating artery, using a left internal carotid artery approach. Case #2: A 70-year old female presented with acute occlusion of the left MCA and tandem occlusion of the cervical left internal carotid artery. Multiple attempts to catheterize the left common carotid artery were unsuccessful. She underwent successful stent retriever mechanical thrombectomy across a patent anterior communicating artery, using a right internal carotid artery approach.

CONCLUSIONS

Timely recanalization of an occluded artery plays a critical role in the prognosis of patients with acute ischemic stroke. Successful stent retriever mechanical thrombectomy of an occluded MCA is possible using a transanterior communicating artery approach in patients without a direct access route to the occluded intracranial vessel. We review the pathophysiology of tandem lesions, access routes to intracranial occlusions, and the literature on cross-circulation techniques to treat emergent large-vessel occlusions.

Spontaneous Bilateral Carotid-Cavernous Fistulas Secondary to Cavernous Sinus Thrombosis

Bilateral carotid cavernous fistulas are rare entities that can cause debilitating symptoms and can lead to more severe consequences if left untreated. Therefore, the recognition and adequate treatment of these pathologies is very important. We present 2 cases of bilateral carotid cavernous fistulas that arose as a result of cavernous sinus thrombosis. We review the literature and discuss the pathophysiology, symptomatology, management, and treatment of bilateral carotid cavernous fistulas. Within our own cases, treatment of the patients was varied. The patient in case 1 was successfully treated with endovascular therapy after a failed trial of anticoagulation. The patient in case 2 demonstrated resolution of bilateral carotid cavernous fistulas after anticoagulation therapy. Case 2 highlights the fact that certain cases of bilateral carotid cavernous fistulas due to cavernous sinus thrombosis may benefit from extensive anticoagulation therapy. If anticoagulation therapy is unsuccessful, endovascular therapy may prove beneficial in resolving the fistulous shunt.

Traumatic brain injury and intracranial hemorrhage–induced cerebral vasospasm: a systematic review

OBJECTIVE

Little is known regarding the natural history of posttraumatic vasospasm. The authors review the pathophysiology of posttraumatic vasospasm (PTV), its associated risk factors, the efficacy of the technologies used to detect PTV, and the management/treatment options available today.

METHODS

The authors performed a systematic review in accordance with the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines using the following databases: PubMed, Google Scholar, and CENTRAL (the Cochrane Central Register of Controlled Trials). Outcome variables extracted from each study included epidemiology, pathophysiology, time course, predictors of PTV and delayed cerebral ischemia (DCI), optimal means of surveillance and evaluation of PTV, application of multimodality monitoring, modern management and treatment options, and patient outcomes after PTV. Study types were limited to retrospective chart reviews, database reviews, and prospective studies.

RESULTS

A total of 40 articles were included in the systematic review. In many cases of mild or moderate traumatic brain injury (TBI), imaging or ultrasonographic studies are not performed. The lack of widespread assessment makes finding the true overall incidence of PTV a difficult endeavor. The clinical consequences of PTV are important, given the morbidity that can result from it. DCI manifests as new-onset neurological deterioration that occurs beyond the timeframe of initial brain injury. While there are many techniques that attempt to diagnose cerebral vasospasm, digital subtraction angiography is the gold standard. Some predictors of PTV include SAH, intraventricular hemorrhage, low admission Glasgow Coma Scale (GCS) score (< 9), and young age (< 30 years).

CONCLUSIONS

Given these results, clinicians should suspect PTV in young patients presenting with intracranial hemorrhage (ICH), especially SAH and/or intraventricular hemorrhage, who present with a GCS score less than 9. Monitoring and regulation of CNS metabolism following TBI/ICH-induced vasospasm may play an important adjunct role to the primary prevention of vasospasm.

Emerging Markers of Early Brain Injury and Delayed Cerebral Ischemia in Aneurysmal Subarachnoid Hemorrhage

BACKGROUND

Delayed cerebral ischemia after aneurysmal subarachnoid hemorrhage is characterized by a highly complex pathophysiology and results in neurologic deterioration after the inciting bleed. Despite its significant consequences, prompt diagnosis can be elusive and treatment is often administered too late. Early brain injury, which occurs within the first 72 hours after ictus, may be an important factor for delayed cerebral ischemia and poor overall outcome. Here, we explore the purported clinical and pathologic manifestations of early brain injury to identify biomarkers that could have prognostic value.

METHODS

We review the literature and discuss potential emerging markers of delayed cerebral ischemia in the context of early brain injury.

RESULTS

The following clinical features and biomarkers were examined: global cerebral edema, ictal loss of consciousness, ultra early angiographic vasospasm, continuous electroencephalogram monitoring, systemic inflammatory response syndrome, cellular mediators of the inflammatory response, and hematologic derangements.

CONCLUSIONS

Some of these markers possess independent value for determining the risk of complications after aneurysmal subarachnoid hemorrhage. However, their use is limited because of a variety of factors, but they do provide an avenue of further study to aid in diagnosis and management.

Cerebral Ischemic Reperfusion Injury Following Recanalization of Large Vessel Occlusions

Although stroke has recently dropped to become the nation's fifth leading cause of mortality, it remains the top leading cause of morbidity and disability in the US. Recent advances in stroke treatment, including intravenous fibrinolysis and mechanical thromboembolectomy, allow treatment of a greater proportion of stroke patients than ever before. While intra-arterial fibrinolysis with recombinant tissue plasminogen is an effective for treatment of a broad range of acute ischemic strokes, endovascular mechanical thromboembolectomy procedures treat severe strokes due to large artery occlusions, often resistant to intravenous drug. Together, these procedures result in a greater proportion of revascularized stroke patients than ever before, up to 88% in 1 recent trial (EXTEND-IA). Subsequently, there is a growing need for neurointensivists to develop more effective strategies to manage stroke patients following successful reperfusion. Cerebral ischemic reperfusion injury (CIRI) is defined as deterioration of brain tissue suffered from ischemia that concomitantly reverses the benefits of re-establishing cerebral blood flow following mechanical or chemical therapies for acute ischemic stroke. Herein, we examine the pathophysiology of CIRI, imaging modalities, and potential neuroprotective strategies. Additionally, we sought to lay down a potential treatment approach for patients with CIRI following emergent endovascular recanalization for acute ischemic stroke.

Anchoring Pipeline Flow Diverter Construct in the Treatment of Traumatic Distal Cervical Carotid Artery Injury

Background

Traumatic extracranial internal carotid artery (ICA) dissections are uncommon and can be difficult to treat. Thinning of adventitia and dilatation may occur following arterial dissection, thus resulting in a fusiform pseudoaneurysm, which can subsequently cause bleeding, expanding, or pulsatile hematoma. Currently, medical management with anticoagulation remains the first line of treatment and yields good outcomes in 75% of cases with a mortality rate of 3-4%. Endovascular intervention is indicated with failure of medical therapy, progressive enlargement of a traumatic pseudoaneurysm, acute flow-related infarcts due to vessel occlusion, or when anticoagulation is contraindicated due to risk of pseudoaneurysm rupture and hemorrhage. Recognized interventional treatments include parent artery occlusion with or without revascularization, endovascular coil embolization, and covered stenting.

Summary

A wide variety of endovascular stents are available that are capable of opening a stenosed vessel while obliterating the associated false lumen and providing a scaffold for embolization of the pseudoaneurysm. The use of the Pipeline Embolization Device (PED) in the management of traumatic intracranial pseudoaneurysms has been described. However, there are few reports on the usage of the PED for treating traumatic extracranial ICA dissection and/or pseudoaneurysms. However, a potential complication of the use of PED in the extracranial ICA is a hypothetical tendency to migrate in a mobile vessel. Thus, the risk of migration of the PED has encouraged practitioners to adopt strategies to limit this risk.

Key Messages

We describe different techniques employed to anchor the flow-diverting construct within tortuous, mobile vessels.

Emergent carotid stenting and intra-arterial abciximab in acute ischemic stroke due to tandem occlusion

OBJECTIVE

Acute occlusions of the extracranial internal carotid artery (ICA) and a major intracranial artery respond poorly to intravenous tissue plasminogen activator (tPA) and present an endovascular challenge. The aim of our study was to retrospectively delineate the feasibility of the combined use of emergent carotid stenting and intra-arterial (IA) Abciximab with intracranial revascularization in the setting of acute ischemic stroke and carotid occlusions at our institution.

METHODS

Eleven patients with complete cervical carotid occlusion with or without concomitant intracranial ICA and/or MCA occlusion were identified from a single center, retrospective review of patients admitted to the Stroke unit. We evaluated all cases for complications of emergent cervical ICA recanalization employing carotid stenting and IA Abciximab.

RESULTS

All patients had complete cervical carotid occlusion with (n = 8) or without (n = 3) concomitant intracranial ICA and/or MCA occlusion. Successful emergent cervical ICA recanalization was achieved in all cases. All patients were administered IA Abciximab (dose range 6-17 mg, average 11.4 mg) immediately following the cervical carotid stenting. There was complete recanalization in all patients with no procedural morbidity or mortality. A single case (1/11, 9%) developed asymptomatic hemorrhagic transformation. Upon discharge, 9 patients (9/11, 82%) had a mRS of 0-2 and 2 patients (2/11, 18%) had a mRS of 3.

CONCLUSIONS

In acute ICA-MCA/distal ICA occlusions, extracranial stenting followed by intracranial IA Abciximab and thrombectomy appears feasible, effective, and safe. Further evaluation of this treatment strategy is warranted.