Progressive microvascular failure in acute ischemic stroke: A systematic review, meta-analysis, and time-course analysis

This systematic review, meta-analysis, and novel time course analysis examines microvascular failure in the treatment of acute ischemic stroke (AIS) patients undergoing endovascular therapy (EVT) and/or thrombolytic administration for stroke management. A systematic review and meta-analysis following PRIMSA-2020 guidelines was conducted along with a novel curve-of-best fit analysis to elucidate the time-course of microvascular failure. Scopus and PubMed were searched using relevant keywords to identify studies that examine recanalization and reperfusion assessment of AIS patients following large vessel occlusion. Meta-analysis was conducted using a random-effects model. Curve-of-best-fit analysis of microvascular failure rate was performed with a negative exponential model. Twenty-seven studies with 1151 patients were included. Fourteen studies evaluated patients within a standard stroke onset-to-treatment time window (≤6 hours after last known normal) and thirteen studies had an extended time window (>6 hours). Our analysis yields a 22% event rate of microvascular failure following successful recanalization (95% CI: 16-30%). A negative exponential curve modeled a microvascular failure rate asymptote of 28.5% for standard time window studies, with no convergence of the model for extended time window studies. Progressive microvascular failure is a phenomenon that is increasingly identified in clinical studies of AIS patients undergoing revascularization treatment.

Mechanical thrombectomy after acute ischemic stroke in patients with left ventricular assist devices: A nationwide analysis

INTRODUCTION

Left ventricular assist devices (LVADs) are an established, durable, and life-saving treatment option for patients with advanced heart failure. However, large vessel occlusions (LVOs) remain one of its most devastating embolic complications. Mechanical thrombectomy (MT) is safe and effective in the management of LVOs in the general population, but LVO trials largely excluded patients on mechanical circulatory support, and large-scale analyses of outcomes following these interventions in the LVAD population are lacking.

METHODS

Using the National Inpatient Sample, we identified all adult patients hospitalized with acute ischemic stroke (AIS) from 2005 to 2018. Regression models adjusting for patient demographics, hospital factors, and clinical severity were used to compare outcomes following MT in patients with and without LVAD. Subgroup analyses were also performed in LVAD patients experiencing stroke in the post-operative setting and stroke in the setting of pre-existing devices.

RESULTS

Of the 1,633,234 AIS hospitalizations identified, 794 occurred in patients with LVADs. Around 61% were post-operative. Post-stroke in-hospital mortality was higher among patients with LVADs (23.3% vs 7.23%, P < 0.001). Among those receiving MT, mortality was also higher in the LVAD population (31.0% vs 14.1%, P = 0.009), though this was largely driven by the post-operative LVAD subgroup. In multivariable analysis, only post-operative LVAD patients experienced greater odds of in-hospital death after MT (adjusted odds ratio (aOR): 8.66, confidence interval (CI):1.46-51.3); patients with pre-existing LVADs demonstrated no difference in post-MT mortality (aOR: 1.06; 95% CI: 0.29-3.91) or in odds of discharge home after MT (aOR 0.63, CI: 0.17-2.32).

CONCLUSION

Our data suggest MT is not a futile treatment approach in patients with pre-existing LVADs and may result in similar rates of good outcomes. Additional research is needed to evaluate the long-term benefits of endovascular therapy after stroke in patients on LVAD support.

Abstract 119: Elevating The Cerebrovascular Nurse Practitioner: Program Development With Neurosurgeon Champions

Background: The cerebrovascular nurse practitioner (NP) continues to have an ever-evolving role, particularly in neurosurgical departments. Although more NPs are obtaining their doctorate degrees, further post professional education is needed to promote specialty clinical practice. Our team developed a 16-week comprehensive educational program that addresses the main disease processes of stroke and highlights the importance of collaboration with cerebrovascular neurosurgeons.

Methods: Four clinical domains were identified- see table 1. Each week, a neurosurgeon gave a 1 hour lecture that reviewed neuroimaging and anatomy, pathophysiology, clinical care presentation, and preoperative and postoperative management. After all lectures were completed for each domain, a 1 hour journal club was held discussing the most recent stroke clinical practice guidelines. NPs were surveyed to report which domains were most clinically meaningful.

Results: Our division delivered a comprehensive educational program, allowing the cerebrovascular NP to take on a more independent role in patient care. Of the sections presented in each clinical domain, neuroimaging and clinical management were reported as the most important section of the lectures by NPs.

Discussion: The cerebrovascular NP plays a unique role on the clinical team, regardless if a patient is seen throughout the entire continuum as an elective case or treated emergently and later discharged to clinic. This program optimized evidence-based cerebrovascular practices, improved collaborating relationships between NP and surgeon, and promoted professional development. Future work will include course evaluation for on-boarding NPs and program implementation in other neurosurgical subspecialties.

Abstract TMP64: Outcomes After Mechanical Thrombectomy In Patients With Left Ventricular Assist Devices

Background: Left ventricular assist devices (LVADs) are an established durable and lifesaving treatment option for patients with advanced heart failure. However, large vessel occlusions (LVOs) remain one of its most devastating embolic complications. Mechanical thrombectomy (MT) is safe and effective in the management of LVOs in the general population but LVO trials largely excluded patients on mechanical circulatory support and large-scale analyses of outcomes following these interventions in the LVAD population are lacking.

Methods: Using the National Inpatient Sample (2012 - 2018) we identified all adult patients hospitalized with acute ischemic stroke (AIS). The presence of LVAD, the use of MT, and additional covariates were extracted. Descriptive statistics and multivariable regression models were used to compare outcomes following MT in patients with and without LVADs.

Results: Of the 798,059 AIS hospitalizations identified, 366 occurred in patients with LVADs. LVAD patients were younger (mean age 59.6 [13.2] vs 70.1 [14.3], p <0.001), and were less often female (23.0% vs 50.9%, p <0.001). In the general stroke population 2% were treated with MT vs 6% in LVAD-associated AIS. Post-stroke mortality was higher among LVAD patients (18.4% vs 6.22, p=0.000). However, among patients receiving MT, there was no significant difference in in-hospital mortality between LVAD and non-LVAD patients (23.1% vs 12.5%, p=0.104). In crude analysis and after adjusting for potential confounders there was no difference in odds of discharge to home after treatment with MT (Figure).

Conclusion: Our data suggests MT is not a futile treatment approach in patients with LVADs and may result in similar rates of good outcomes. Additional research is needed to evaluate the long-term benefits of endovascular therapy after stroke in patients on LVAD support.

Delayed-Onset Cranial Nerve Palsy After Transvenous Embolization of Indirect Carotid Cavernous Fistulas

BACKGROUND

Carotid cavernous fistulas (CCF) often present with diplopia secondary to cranial nerve palsy (CNP). Immediate development of postoperative CNP has been described in the literature. This study described delayed-onset of CNP after complete and reconfirmed obliteration of the CCF and resolution of initial CNP.

METHODS

A retrospective analysis was performed on patients with indirect CCF between 1987 and 2006 at 4 academic endovascular centers. Details of the endovascular procedures, embolic agents used, and complications were studied. Partial or complete obliteration was determined. Immediate and delayed cranial nerve palsies were independently assessed.

RESULTS

A total of 267 patients with symptomatic indirect CCF underwent transvenous endovascular treatment. Four patients (1.5%) developed delayed abducens nerve (VI) palsy after complete resolution of presenting symptoms after embolization. Delayed presentation ranged between 3 and 13 months after complete resolution of initial double vision and cranial nerve palsies. Transvenous coil embolization through the inferior petrosal sinus was performed in all 4 affected patients. All had follow-up angiography confirming durable closure of their CCF. MRI did not show new mass lesions or abnormal soft tissue enhancement. In all 4 patients, their abducens nerve (VI) palsy remained.

CONCLUSIONS

Delayed CNP can develop despite complete endovascular obliteration of the CCF. The cause of delayed CNP is not yet determined, but may represent fibrosis and ischemia. Long-term follow-up is needed even after complete neurological and radiological recovery is attained in the immediate perioperative period.

Stroke and mechanical thrombectomy in patients with COVID-19: technical observations and patient characteristics

BACKGROUND

COVID-19 infections have been shown to be associated with a range of thromboembolic disease.

OBJECTIVE

To describe our endovascular experience in a consecutive series of patients with COVID-19 who presented with large vessel occlusions, and to describe unique findings in this population.

METHODS

Mechanical thrombectomy was performed on five consecutive patients with COVID-19 with large vessel occlusions. A retrospective study of these patients was performed. Patient demographics, laboratory values, mechanical thrombectomy technique, and clinical and angiographic outcomes were reviewed.

RESULTS

Four patients with COVID-19 presented with anterior circulation occlusions and one patient with COVID-19 presented with both anterior and posterior circulation occlusions. All patients had coagulation abnormalities. Mean patient age was 52.8 years. Three patients presented with an intracranial internal carotid artery occlusion. Two patients presented with an intracranial occlusion and a tandem thrombus in the carotid bulb. One patient presented with an occlusion in both the internal carotid and basilar arteries. Clot fragmentation and distal emboli to a new vascular territory were seen in two of five (40%) patients, and downstream emboli were seen in all five (100%) patients. Patient clinical outcome was generally poor in this series of patients with COVID-19 large vessel occlusion.

CONCLUSION

Our series of patients with COVID-19 demonstrated coagulation abnormalities, and compared with our previous experience with mechanical thrombectomy in large vessel occlusion, this group of patients were younger, had tandem or multiple territory occlusions, a large clot burden, and a propensity for clot fragmentation. These patients present unique challenges that make successful revascularization difficult.

Curative treatment for low-grade arteriovenous malformations

Background

Spetzler-Martin (SM) grade I-II (low-grade) arteriovenous malformations (AVMs) are often considered safe for microsurgery or radiosurgery. The adjunctive use of preoperative embolization to reduce surgical risk in these AVMs remains controversial.

Objective

To assess the safety of combined treatment of grade I-II AVMs with preoperative embolization followed by surgical resection or radiosurgery, and determine the long-term functional outcomes.

Methods

With institutional review board approval, a retrospective analysis was carried out on patients with ruptured and unruptured SM I-II AVMs between 2002 and 2017. Details of the endovascular procedures, including number of arteries supplying the AVM, number of branches embolized, embolic agent(s) used, and complications were studied. Baseline clinical and imaging characteristics were compared. Functional status using the modified Rankin Scale (mRS) before and after endovascular and microsurgical treatments was compared.

Results

258 SM I-II AVMs (36% SM I, 64% SM II) were identified in patients with a mean age of 38 ± 17 years. 48% presented with hemorrhage, 21% with seizure, 16% with headache, 10% with no symptoms, and 5% with clinical deficits. 90 patients (68%) in the unruptured group and 74 patients (59%) in the ruptured group underwent presurgical embolization (p = 0.0013). The mean number of arteries supplying the AVM was 1.44 and 1.41 in the unruptured and ruptured groups, respectively (p = 0.75). The mean number of arteries embolized was 2.51 in the unruptured group and 1.82 in the ruptured group (p = 0.003). n-Butyl cyanoacrylate and Onyx were the two most commonly used embolic agents. Four complications were seen in four patients (4/164 patients embolized): two peri-/postprocedural hemorrhage, one dissection, and one infarct. All patients undergoing surgery had a complete cure on postoperative angiography. Patients were followed up for a mean of 55 months. Good long-term outcomes (mRS score ≤ 2) were seen in 92.5% of patients with unruptured AVMs and 88.0% of those with ruptured AVMs. Permanent neurological morbidity occurred in 1.2%.

Conclusions

Curative treatment of SM I-II AVMs can be performed using endovascular embolization with microsurgical resection or radiosurgery in selected cases, with very low morbidity and high cure rates. Compared with other published series, these outcomes suggest that preoperative embolization is a safe and effective adjunct to definitive surgical treatment. Long-term follow-up showed that patients with low-grade AVMs undergoing surgical resection or radiosurgery have good functional outcomes.

Cerebral Vasospasm after Open Fenestration of an Arachnoid Cyst in a 4-Year-Old Boy: Case Report and Review of the Literature

Cerebral vasospasm is associated with significant morbidity, and most commonly occurs following subarachnoid hemorrhage. Rarely, vasospasm can follow tumor resection and traumatic brain injury. We present the first reported case of a young child who developed diffuse vasospasm following open fenestration of an arachnoid cyst and was promptly treated, with full recovery of neurologic function. Although vasopasm after arachnoid cyst fenestration is rare, it can be included in the differential for a new focal neurologic deficit.

Functional Outcomes and Delayed Cerebral Ischemia Following Nonperimesencephalic Angiogram-Negative Subarachnoid Hemorrhage Similar to Aneurysmal Subarachnoid Hemorrhage

BACKGROUND

The angiogram-negative subarachnoid hemorrhage (SAH) literature includes patients with perimesencephalic hemorrhage, which is recognized to have a much better outcome than aneurysmal SAH.

OBJECTIVE

To evaluate the clinical outcomes of Nonperimesencephalic Angiogram-Negative SAH (NPAN-SAH).

METHODS

A prospective, spontaneous SAH database of 1311 patients that accrued between April 2006 and December 2014 was screened. All patients with NPAN-SAH and 2 consecutive negative cerebral angiograms were included.

RESULTS

We identified 191 (11%) from a total of 1311 patients with spontaneous SAH. Amongst angiogram-negative patients, 83 (4.9%) were adjudicated to have NPAN-SAH. Patient characteristics were similar across the groups, except NPAN-SAH patients were more likely to be men and had higher rates of diabetes. In a multivariable logistic regression model, NPAN-SAH patients were less likely to develop vasospasm, after adjusting for Fisher grade, sex, and diabetes (odds ratio [OR]: 0.197, 95% confidence interval [CI; 0.07-0.55], P = .002). In another adjusted model accounting for Hunt and Hess clinical grade, NPAN-SAH patients were also less likely to develop vasospasm (OR: 0.2, 95% CI [0.07-0.57], P = .002). We found no statistical significance between 2 groups for rebleed, developing hydrocephalus, seizures, or delayed cerebral ischemia. NPAN-SAH patients were equally associated with poor functional outcome (modified Rankin scale ≥3; OR: 1.16, 95% CI [0.615-2.20], P = .6420), and death (OR: 1.22, 95% CI [0.362-4.132], P = .7455) compared to aneurysmal SAH.

CONCLUSION

Although the risk of vasospasm may be lower, patients with NPAN-SAH are equally associated with delayed cerebral ischemia, poor outcome, and death as compared to patients with aneurysmal SAH. Furthers studies may be necessary to further clarify these findings

Reassessing the Role of Intra-Arterial Drug Delivery for Glioblastoma Multiforme Treatment

Effective treatment for glioblastoma (GBM) will likely require targeted delivery of several specific pharmacological agents simultaneously. Intra-arterial (IA) delivery is one technique for targeting the tumor site with multiple agents. Although IA chemotherapy for glioblastoma (GBM) has been attempted since the 1950s, the predicted benefits remain unproven in clinical practice. This review focuses on innovative approaches to IA drug delivery in treating GBM. Guided by novel in vitro and in vivo optical measurements, newer pharmacokinetic models promise to better define the complex relationship between background cerebral blood flow and drug injection parameters. Advanced optical technologies and tracers, unique nanoparticles designs, new cellular targets, and rational drug formulations are continuously modifying the therapeutic landscape for GBM. Personalized treatment approaches are emerging; however, such tailored approaches will largely depend on effective drug delivery techniques and on the ability to simultaneously deliver multidrug regimens. These new paradigms for tumor-selective drug delivery herald dramatic improvements in the effectiveness of IA chemotherapy for GBM. Therefore, within this context of so-called "precision medicine," the role of IA delivery for GBM is thoroughly reassessed.

Role of embolization for cerebral arteriovenous malformations

Cerebral arteriovenous malformations (AVMs) are complex high-flow lesions that can result in devastating neurological injury when they hemorrhage. Embolization is a critical component in the management of many patients with cerebral AVMs. Embolization may be used as an independent curative therapy or more commonly in an adjuvant fashion prior to either micro- or radiosurgery. Although the treatment-related morbidity and mortality for AVMs--including that due to microsurgery, embolization, and radiosurgery--can be substantial, its natural history offers little solace. Fortunately, care by a multidisciplinary team experienced in the comprehensive management of AVMs can offer excellent results in most cases.

The role of antiplatelet medications in angiogram-negative subarachnoid hemorrhage

BACKGROUND

The use of antiplatelet medications has greatly expanded and this has been associated with an increased rate of complications after aneurysmal subarachnoid hemorrhage (SAH). The influence of antiplatelet medications on outcomes after non-aneurysmal SAH is unknown.

OBJECTIVE

To analyze the frequency and impact on outcome of antiplatelet medication use among patients with angiogram-negative SAH.

METHODS

An analysis of patients within the Columbia University SAH Outcomes Project database was performed. All patients who underwent catheter cerebral angiography after presenting with nontraumatic SAH between 1996 and 2013 were included. Outcomes were assessed by using the modified Rankin Scale.

RESULTS

A total of 1351 patients underwent catheter angiography for evaluation of SAH. Of these, 173 (13%) were designated angiogram-negative. The fraction of patients presenting with angiogram-negative SAH as well as the frequency of antiplatelet use among these patients significantly increased during the study period. Antiplatelet use was more commonly associated with angiogram-negative SAH than with angiogram-positive SAH (27% vs 14%, P = .001). At 14 days after presentation, poor outcome was significantly more frequent among patients who took antiplatelet agents than among those who did not (38% vs 20%, P = .017). This effect was also seen after multivariate analysis (odds ratio, 2.58; P = .034), although no difference was observed by 12 months (P > .05).

CONCLUSION

Antiplatelet medication use is associated with poor early, but not late, outcomes after angiogram-negative SAH. Corresponding increased rates of antiplatelet medication use and angiogram-negative SAH may be related. Additional studies are needed to confirm this association.

Late onset aneurysm development following radiosurgical obliteration of a cerebellopontine angle meningioma

The development of de novo intracranial aneurysms following stereotactic radiosurgery for intracranial pathology is a rare complication secondary to vascular injury. Typically, these aneurysms develop within the first few years after radiation surgery. We present the first case of an aneurysm developing 10 years after radiosurgery for a cerebellopontine angle meningioma. This case highlights the importance of careful long-term follow-up of patients who undergo radiosurgery for lesions abutting major vessels and/or who suffer post-radiation complications.

Late onset aneurysm development following radiosurgical obliteration of a cerebellopontine angle meningioma

The development of de novo intracranial aneurysms following stereotactic radiosurgery for intracranial pathology is a rare complication secondary to vascular injury. Typically, these aneurysms develop within the first few years after radiation surgery. We present the first case of an aneurysm developing 10 years after radiosurgery for a cerebellopontine angle meningioma. This case highlights the importance of careful long-term follow-up of patients who undergo radiosurgery for lesions abutting major vessels and/or who suffer post-radiation complications.

Spinal arteriovenous malformation associated with Schimmelpenning syndrome

The authors report the presentation and management of a 13-year-old girl with Schimmelpenning syndrome, a rare neurocutaneous syndrome; this patient suffered hemorrhage of a spinal arteriovenous malformation. This is the first case of a spinal arteriovenous malformation reported in association with Schimmelpenning syndrome. Neurosurgeons should be aware of this rare phacomatosis as well as of the various neurological disorders associated with this diagnosis. The threshold for imaging the neuraxis in these patients should be low.

Improving patient selection for endovascular treatment of acute cerebral ischemia: a review of the literature and an external validation of the Houston IAT and THRIVE predictive scoring systems

Outcome after intraarterial therapy (IAT) for acute ischemic stroke remains variable, suggesting that improved patient selection is needed to better identify patients likely to benefit from treatment. The authors evaluate the predictive accuracies of the Houston IAT (HIAT) and the Totaled Health Risks in Vascular Events (THRIVE) scores in an independent cohort and review the existing literature detailing additional predictive factors to be used in patient selection for IAT. They reviewed their center's endovascular records from January 2004 to July 2010 and identified patients who had acute ischemic stroke and underwent IAT. They calculated individual HIAT and THRIVE scores using patient age, admission National Institutes of Health Stroke Scale (NIHSS) score, admission glucose level, and medical history. The scores' predictive accuracies for good outcome (discharge modified Rankin Scale score ≤ 3) were analyzed using receiver operating characteristics analysis. The THRIVE score predicts poor outcome after IAT with reasonable accuracy and may perform better than the HIAT score. Nevertheless, both measures may have significant clinical utility; further validation in larger cohorts that accounts for differences in patient demographic characteristics, variation in time-to-treatment, and center preferences with respect to IAT modalities is needed. Additional patient predictive factors have been reported but not yet incorporated into predictive scales; the authors suggest the need for additional data analysis to determine the independent predictive value of patient admission NIHSS score, age, admission hyperglycemia, patient comorbidities, thrombus burden, collateral flow, time to treatment, and baseline neuroimaging findings.

Arteriovenous malformation-associated aneurysms in the pediatric population

OBJECT

Conventional cerebral angiography and treatment for ruptured arteriovenous malformations (AVMs) in children are often performed in a delayed fashion. In adults, current literature suggests that AVM-associated aneurysms may be more likely to hemorrhage than isolated AVMs, which often leads to earlier angiography and endovascular treatment of associated aneurysms. The nature of AVM-associated aneurysms in the pediatric population is virtually unknown. In this report, the authors investigate the relationship of associated aneurysms in a large group of children with AVMs.

METHODS

Seventy-seven pediatric patients (≤ 21 years old) with AVMs were treated at the Columbia University Medical Center between 1991 and 2010. Medical records and imaging studies were retrospectively reviewed, and associated aneurysms were classified as arterial, intranidal, or venous in location. Clinical presentation and outcome variables were compared between children with and without AVM-associated aneurysms.

RESULTS

A total of 30 AVM-associated aneurysms were found in 22 children (29% incidence). Eleven were arterial, 9 intranidal, and 10 were venous in location. There was no significant difference in the rate of hemorrhage (p = 0.91) between children with isolated AVMs (35 of 55 [64%]) and children with AVM-associated aneurysms (13 of 22 [59%]). However, of the 11 children with AVM-associated aneurysms in an arterial location, 10 presented with hemorrhage (91%). An association with hemorrhage was significant in univariate analysis (p = 0.045) but not in multivariate analysis (p = 0.37).

CONCLUSIONS

Associated aneurysms are present in nearly a third of children with AVMs, and when arterially located, are more likely to present with hemorrhage. These data suggest that early angiography with endovascular treatment of arterial-based aneurysms in children with AVMs may be indicated.

Pre-operative intracranial meningioma embolization

Pre-operative embolization is a routinely utilized therapeutic adjunct to the resection of hypervascular lesions of the head and neck. In particular, pre-operative cerebral angiography and tumor embolization has become standard practice at many centers in the management of select intracranial meningiomas. However, controversy remains regarding its specific indications and clinical utility. In this article, we examine the principles of meningioma embolization, emphasizing the indications, risks and benefits associated with its use in the pre-operative setting.

Complex basilar artery aneurysms treated using surgical basilar occlusion: a modern case series

Object

Complex aneurysms of the basilar artery (BA) apex can be successfully treated using surgical occlusion of the proximal BA. Since the introduction of the Guglielmi detachable coil in 1991, the focus on treating BA aneurysms has been on using endovascular techniques. Outcomes with endovascular techniques have been less than optimal for large and complex aneurysms. The authors therefore report on their current 22-year experience with surgical BA occlusion for complex BA aneurysms and long-term outcome.

Methods

Fifteen patients underwent surgical BA occlusion at Columbia University Medical Center for complex basilar apex aneurysms between 1987 and 2009. The clinical records of each patient were reviewed for details of presentation, hospital course, operative intervention, and outcome.

Results

Postoperatively, all patient encounters were recorded at discharge, at the 1-month and 1-year follow-up evaluations, and at long-term outcome. Twelve (80%) of 15 patients experienced no new postoperative neurological deficits. Three patients presenting with severe neurological impairment (modified Rankin Scale [mRS] score > 3) made excellent recoveries (mRS Scores 1–2) at long-term follow-up. One patient died, 1 suffered a stroke during the postoperative angiogram which resulted in hemiparesis, and 1 suffered internuclear ophthalmoplegia which resolved by the 1-month follow-up. Long-term follow-up occurred at an average of 3 ± 4.5 years, ranging from 2 months (for a recently treated patient) to 18 years. The average mRS score at long-term follow-up was 1 ± 1.5. No patient experienced postoperative hemorrhage, rebleeding, or delayed neurological deterioration.

Conclusions

Surgical occlusion of the BA is an effective treatment option offering a high rate of angiographic cure in a single procedure for patients with complex BA aneurysms. The ability to surgically perform point occlusion of the BA without impairment of brainstem perforators, while maintaining collateral blood flow to the posterior circulation branch vessels, may provide an advantage compared with endovascular treatments.

Reporting standards for endovascular repair of saccular intracranial cerebral aneurysms

BACKGROUND AND PURPOSE

The goal of this article is to provide consensus recommendations for reporting standards, terminology, and written definitions when reporting on the radiological evaluation and endovascular treatment of intracranial, cerebral aneurysms. These criteria can be used to design clinical trials, to provide uniformity of definitions for appropriate selection and stratification of patients, and to allow analysis and meta-analysis of reported data.

METHODS

This article was written under the auspices of the Joint Writing Group of the Technology Assessment Committee, Society of Neurolnterventional Surgery, Society of Interventional Radiology; Joint Section on Cerebrovascular Neurosurgery of the American Association of Neurological Surgeons and Congress of Neurological Surgeons; and Section of Stroke and Interventional Neurology of the American Academy of Neurology. A computerized search of the National Library of Medicine database of literature (PubMed) from January 1991 to December 2007 was conducted with the goal to identify published endovascular cerebrovascular interventional data about the assessment and endovascular treatment of cerebral aneurysms useful as benchmarks for quality assessment. We sought to identify those risk adjustment variables that affect the likelihood of success and complications. This article offers the rationale for different clinical and technical considerations that may be important during the design of clinical trials for endovascular treatment of cerebral aneurysms. Included in this guidance article are suggestions for uniform reporting standards for such trials. These definitions and standards are primarily intended for research purposes; however, they should also be helpful in clinical practice and applicable to all publications.

CONCLUSIONS

The evaluation and treatment of brain aneurysms often involve multiple medical specialties. Recent reviews by the American Heart Association have surveyed the medical literature to develop guidelines for the clinical management of ruptured and unruptured cerebral aneurysms. Despite efforts to synthesize existing knowledge on cerebral aneurysm evaluation and treatment, significant inconsistencies remain in nomenclature and definition for research and reporting purposes. These operational definitions were selected by consensus of a multidisciplinary writing group to provide consistency for reporting on imaging in clinical trials and observational studies involving cerebral aneurysms. These definitions should help different groups to publish results that are directly comparable.

Systemic Expression of Matrix Metalloproteinase-9 in Patients With Cerebral Arteriovenous Malformations

OBJECTIVE

Increased expression angiogenic factors, such as matrix metalloproteinases (MMPs), are associated with the formation of cerebral arteriovenous malformations (AVMs). The objective of this study was to determine plasma levels of MMP-9 of patients with AVMs.

METHODS

Blood samples were drawn from 15 patients with AVMs before treatment, 24 hours postembolization, 24 hours postresection, and 30 days postresection. Blood samples were also obtained from 30 healthy controls. Plasma MMP-9 concentrations were measured via enzyme-linked immunosorbent assay.

RESULTS

The mean plasma MMP-9 level in AVM patients at baseline was significantly higher than in control patients: 108.04 ± 16.11 versus 41.44 ± 2.44 ng/mL, respectively. The mean plasma MMP-9 level 1 day after embolization increased to 172.35 ± 53.76 ng/mL, which was not significantly elevated over pretreatment levels. One day after resection, plasma MMP-9 levels increased significantly over pretreatment levels to 230.97 ± 51.00 ng/mL. Mean plasma MMP-9 concentrations 30 days after resection decreased to 92.8 ± 18.7 ng/mL, which was not different from pretreatment levels but was still significantly elevated over control levels. MMP-9 levels did not correlate with patient sex, age, presentation, or AVM size.

CONCLUSION

Plasma MMP-9 levels are significantly elevated over controls at baseline, increase significantly immediately after surgery, and decrease to pretreatment levels during follow-up.

Reporting standards for endovascular repair of saccular intracranial cerebral aneurysms

BACKGROUND AND PURPOSE

The goal of this article is to provide consensus recommendations for reporting standards, terminology, and written definitions when reporting on the radiological evaluation and endovascular treatment of intracranial, cerebral aneurysms. These criteria can be used to design clinical trials, to provide uniformity of definitions for appropriate selection and stratification of patients, and to allow analysis and meta-analysis of reported data.

METHODS

This article was written under the auspices of the Joint Writing Group of the Technology Assessment Committee, Society of NeuroInterventional Surgery, Society of Interventional Radiology; Joint Section on Cerebrovascular Neurosurgery of the American Association of Neurological Surgeons and Congress of Neurological Surgeons; and Section of Stroke and Interventional Neurology of the American Academy of Neurology. A computerized search of the National Library of Medicine database of literature (PubMed) from January 1991 to December 2007 was conducted with the goal to identify published endovascular cerebrovascular interventional data about the assessment and endovascular treatment of cerebral aneurysms useful as benchmarks for quality assessment. We sought to identify those risk adjustment variables that affect the likelihood of success and complications. This article offers the rationale for different clinical and technical considerations that may be important during the design of clinical trials for endovascular treatment of cerebral aneurysms. Included in this guidance article are suggestions for uniform reporting standards for such trials. These definitions and standards are primarily intended for research purposes; however, they should also be helpful in clinical practice and applicable to all publications.

CONCLUSIONS

The evaluation and treatment of brain aneurysms often involve multiple medical specialties. Recent reviews by the American Heart Association have surveyed the medical literature to develop guidelines for the clinical management of ruptured and unruptured cerebral aneurysms. Despite efforts to synthesize existing knowledge on cerebral aneurysm evaluation and treatment, significant inconsistencies remain in nomenclature and definition for research and reporting purposes. These operational definitions were selected by consensus of a multidisciplinary writing group to provide consistency for reporting on imaging in clinical trials and observational studies involving cerebral aneurysms. These definitions should help different groups to publish results that are directly comparable.

Incidence of moderate to severe cognitive dysfunction in patients treated with carotid artery stenting

OBJECTIVE

Approximately 25% of patients with carotid artery stenosis treated with carotid endarterectomy develop cognitive dysfunction (CD) between 1 day and 1 month after surgery compared with a control group. We hypothesized that patients with carotid artery stenosis treated with carotid artery stenting (CAS) performed under cerebral embolic protection also develop CD at similar time points compared with a control group.

METHODS

Twenty-four patients scheduled for elective CAS were enrolled in a prospective institutional review board-approved study to evaluate cognitive function with a battery of 6 neuropsychometric tests before, and 1 day and 1 month after, CAS. Test performance was compared with 23 patients undergoing coronary artery procedures (control group). The mean and standard deviation of the difference scores in the control group were used to generate Z scores. We used a previously described point system to transform negative Z scores into injury points for each neuropsychometric test. Global performance is presented as average deficit score (sum of injury points divided by the number of completed tests). All patients underwent the procedures with mild sedation. Results were analyzed in 2 ways: group-rate and event-rate analysis. Outcome was dichotomized by defining moderate to severe CD as average deficit score at least 1.5 standard deviations worse than the control group. Fisher tests and multivariate logistic regression models were used to analyze group performance.

RESULTS

Control patients tended to be younger and had a lower incidence of stroke or previous transient ischemic attack. One day after surgery, 41% of patients (10 of 24) treated with CAS developed moderate to severe CD (P = 0.0422). Average deficit score was also significantly higher in the CAS group at 1 day (P = 0.0265). These differences were independent of age and history of stroke/transient ischemic attack. Interestingly, we found that the absence of oral statin medication may increase the probability of CD. By 1 month, 9% of patients (1 of 11) treated with CAS presented with CD. Other patients were lost to follow-up.

CONCLUSION

CAS is associated with a decline in cognitive performance that is at least moderate 1 day after surgery.

Reporting standards for angioplasty and stent-assisted angioplasty for intracranial atherosclerosis

BACKGROUND AND PURPOSE

Intracranial cerebral atherosclerosis causes ischemic stroke in a significant number of patients. Technological advances over the past 10 years have enabled endovascular treatment of intracranial atherosclerotic stenosis. The number of patients treated with angioplasty or stent-assisted angioplasty for this condition is increasing. Given the lack of universally accepted definitions, the goal of this document is to provide consensus recommendations for reporting standards, terminology, and written definitions when reporting clinical and radiological evaluation, technique, and outcome of endovascular treatment using angioplasty or stent-assisted angioplasty for stenotic and occlusive intracranial atherosclerosis.

SUMMARY OF REPORT

This article was written under the auspices of Joint Writing Group of the Technology Assessment Committee, Society of NeuroInterventional Surgery, Society of Interventional Radiology; Joint Section on Cerebrovascular Neurosurgery of the American Association of Neurological Surgeons and Congress of Neurological Surgeons; and the Section of Stroke and Interventional Neurology of the American Academy of Neurology. A computerized search of the National Library of Medicine database of literature (PubMed) from January 1997 to December 2007 was conducted with the goal to identify published endovascular cerebrovascular interventional data in stenotic intracranial atherosclerosis that could be used as benchmarks for quality assessment. We sought to identify those risk adjustment variables that affect the likelihood of success and complications. This document offers the rationale for different clinical and technical considerations that may be important during the design of clinical trials for endovascular treatment of intracranial stenotic and occlusive atherosclerosis. Included in this guidance document are suggestions for uniform reporting standards for such trials. These definitions and standards are primarily intended for research purposes; however, they should also be helpful in clinical practice and applicable to all publications.

CONCLUSION

In summary, the definitions proposed represent recommendations for constructing useful research data sets. The intent is to facilitate production of scientifically rigorous results capable of reliable comparisons between and among similar studies. In some cases, the definitions contained here are recommended by consensus of a panel of experts in this writing group for consistency in reporting and publication. These definitions should allow different groups to publish results that are directly comparable.

Mechanical treatment of vasospasm

OBJECTIVE

Since cerebral vasospasm (CV) was first described nearly half a century ago, significant progress has been made in understanding its underlying pathophysiology and developing treatment modalities. The purpose of this review is to discuss the rationale behind mechanical interventions for CV as well as the efficacy and complications associated with these treatment options.

METHODS

The authors summarize the pertinent literature on the mechanical treatment of CV, focusing first on balloon angioplasty, second on therapy combined with intra-arterial drug infusion, and concluding by briefly discussing intra-aortic balloon counterpulsation. The epidemiology, pathophysiology, technique, outcome, timing and complications are discussed for each treatment option.

RESULTS

A review of the relevant medical literature reveals that in the last 20 years, endovascular techniques including transluminal balloon angioplasty, intra-arterial drug infusion and newer experimental strategies have provided an important supplement to the established medical therapy.

DISCUSSION

Despite these developments, however, CV remains a major contributor to poor outcome following aSAH and continued efforts are necessary to improve and refine endovascular strategies as well as develop new treatment modalities.

Spontaneous delayed proximal migration of enterprise stent after staged treatment of wide-necked basilar aneurysm: technical case report

OBJECTIVE

To document a unique technical issue with a relatively newly released intravascular stent used for adjunctive treatment of wide-necked cerebral aneurysms.

CLINICAL PRESENTATION

A 48-year-old woman with a sister who had a large unruptured wide-necked basilar aneurysm underwent screening evaluation that revealed a nearly identical aneurysm. She also harbored small unruptured right superior cerebellar and left anterior cerebral artery aneurysms.

INTERVENTION

Endovascular treatment of the 11.5-mm basilar aneurysm was performed in a staged manner. Stent placement was performed first, followed by delayed coil embolization of the aneurysm 9 weeks later. Follow-up angiography at the time of the second procedure revealed significant spontaneous proximal migration of the Enterprise Vascular Reconstruction Device and Delivery System (Cordis Neurovascular, Inc., Miami Lakes, FL) with the distal extent of the device migrating from the right P2 segment into the neck of the aneurysm. Coil embolization was performed despite migration of the vascular reconstruction device.

CONCLUSION

The use of stents in the endovascular treatment of cerebral aneurysms has vastly improved our ability to treat complex lesions. Technical issues remain with these devices, and description of this event may alter the way we use the Enterprise Vascular Reconstruction Device and Delivery System in terms of staging procedures, and when evaluating the particular vascular anatomy of the individual patient with special attention to parent artery vessel size.

Gunshot wounds to the head: Gang- and non-gang-related injuries and outcomes

PRIMARY OBJECTIVE

This study examined the differences between gang and non-gang-related incidents of penetrative missile injuries in terms of demographics, motivation, intra-cranial pathology, transit time, injury time and clinical outcome.

RESEARCH DESIGN

Retrospective and prospective chart review.

METHODS AND PROCEDURES

Between 1985-1992, 349 patients with penetrating missile injuries to the brain presenting to LAC-USC were studied.

EXPERIMENTAL INTERVENTIONS

Inclusion criteria were implemented to keep the cohort as homogenous as possible. Patients excluded were those with multiple gunshot wounds, non-penetrating gunshot wounds to the head, systemic injuries and cases in which the motivation for the incident was unknown.

MAIN OUTCOMES AND RESULTS

Gang-related shooting slightly out-numbered non-gang-related incidents. Demographic analysis showed both a male and Hispanic predominance for both gang- and non-gang-related victims and significant differences in gender, race and age. Occipital entrance sites were more common in the gang-related vs temporal entrance sites in the non-gang-related. Mean transit time to the emergency department for gang-related shootings was less than non-gang-related shootings (24.4 vs 27.8 minutes). Most shooting incidents took place between 6pm and 3am. No difference between survival and outcome was noted between gang and non-gang victims.

CONCLUSIONS

Significant differences were found between gang- and non-gang-related shooting victims in terms of demographics, entrance site and transit time. No difference was found between injury time, survival and outcome between gang and non-gang populations.

Adjuvant embolization with N-butyl cyanoacrylate in the treatment of cerebral arteriovenous malformations: outcomes, complications, and predictors of neurologic deficits

BACKGROUND AND PURPOSE

The purpose of this study was to assess the frequency, severity, and predictors of neurological deficits after adjuvant embolization for cerebral arteriovenous malformations.

METHODS

From 1997 to 2006, 202 of 275 patients with arteriovenous malformation received embolization before microsurgery (n=176) or radiosurgery (n=26). Patients were examined before and after endovascular embolization and at clinical follow-up (mean, 43.4+/-34.6 months). Outcome was classified according to the modified Rankin Scale. New neurological deficits after embolization were defined as minimal (no change in overall modified Rankin Scale), moderate (modified Rankin Scale < or =2), or significant (modified Rankin Scale >2).

RESULTS

Two hundred two patients were treated in 377 embolization procedures. There were a total of 29 new clinical deficits after embolization (8% of procedures; 14% of patients), of which 19 were moderate or significant. Postembolization deficits resolved in a significant number of patients over time (P<0.0001). Five patients had persistent neurological deficits due to embolization (1.3% of procedures; 2.5% of patients). In multivariate analysis, the following variables significantly predicted new neurological deficit after embolization: complex arteriovenous malformation with treatment plan specifying more than one embolization procedure (OR, 2.7; 95% CI, 1.4 to 8.6), diameter <3 cm (OR, 3.2; 95% CI, 1.2 to 9.1), diameter >6 cm (OR, 6.2; 95% CI, 1.0 to 57.0), deep venous drainage (OR, 2.7; 95% CI, 1.1 to 6.9), or eloquent location (OR, 2.4; 95% CI, 1.0 to 5.7). These variables were weighted and used to compute an arteriovenous malformation Embolization Prognostic Risk Score for each patient. A score of 0 predicted no new deficits, a score of 1 predicted a new deficit rate of 6%, a score of 2 predicted a new deficit rate of 15%, a score of 3 predicted a new deficit rate of 21%, and a score of 4 predicted a new deficit rate of 50% (P<0.0001).

CONCLUSIONS

Small and large size, eloquent location, deep venous drainage, and complex vascular anatomy requiring multiple embolization procedures are risk factors for the development of immediate postembolization neurological deficits. Nevertheless, a significant number of patients with treatment-related neurological deficits improve over time. The low incidence of permanent neurological deficits underscores the usefulness of this technique in carefully selected patients.

Reporting Standards for Angioplasty and Stent-Assisted Angioplasty for Intracranial Atherosclerosis

Background and Purpose— Intracranial cerebral atherosclerosis causes ischemic stroke in a significant number of patients. Technological advances over the past 10 years have enabled endovascular treatment of intracranial atherosclerotic stenosis. The number of patients treated with angioplasty or stent-assisted angioplasty for this condition is increasing. Given the lack of universally accepted definitions, the goal of this document is to provide consensus recommendations for reporting standards, terminology, and written definitions when reporting clinical and radiological evaluation, technique, and outcome of endovascular treatment using angioplasty or stent-assisted angioplasty for stenotic and occlusive intracranial atherosclerosis.

Summary of Report— This article was written under the auspices of Joint Writing Group of the Technology Assessment Committee, Society of NeuroInterventional Surgery, Society of Interventional Radiology; Joint Section on Cerebrovascular Neurosurgery of the American Association of Neurological Surgeons and Congress of Neurological Surgeons; and the Section of Stroke and Interventional Neurology of the American Academy of Neurology. A computerized search of the National Library of Medicine database of literature (PubMed) from January 1997 to December 2007 was conducted with the goal to identify published endovascular cerebrovascular interventional data in stenotic intracranial atherosclerosis that could be used as benchmarks for quality assessment. We sought to identify those risk adjustment variables that affect the likelihood of success and complications. This document offers the rationale for different clinical and technical considerations that may be important during the design of clinical trials for endovascular treatment of intracranial stenotic and occlusive atherosclerosis. Included in this guidance document are suggestions for uniform reporting standards for such trials. These definitions and standards are primarily intended for research purposes; however, they should also be helpful in clinical practice and applicable to all publications.

Conclusion— In summary, the definitions proposed represent recommendations for constructing useful research data sets. The intent is to facilitate production of scientifically rigorous results capable of reliable comparisons between and among similar studies. In some cases, the definitions contained here are recommended by consensus of a panel of experts in this writing group for consistency in reporting and publication. These definitions should allow different groups to publish results that are directly comparable.

Reporting standards for endovascular repair of saccular intracranial cerebral aneurysms

BACKGROUND AND PURPOSE

The goal of this article is to provide consensus recommendations for reporting standards, terminology, and written definitions when reporting on the radiological evaluation and endovascular treatment of intracranial, cerebral aneurysms. These criteria can be used to design clinical trials, to provide uniformity of definitions for appropriate selection and stratification of patients, and to allow analysis and meta-analysis of reported data.

METHODS

This article was written under the auspices of the Joint Writing Group of the Technology Assessment Committee, Society of NeuroInterventional Surgery, Society of Interventional Radiology; Joint Section on Cerebrovascular Neurosurgery of the American Association of Neurological Surgeons and Congress of Neurological Surgeons; and Section of Stroke and Interventional Neurology of the American Academy of Neurology. A computerized search of the National Library of Medicine database of literature (PubMed) from January 1991 to December 2007 was conducted with the goal to identify published endovascular cerebrovascular interventional data about the assessment and endovascular treatment of cerebral aneurysms useful as benchmarks for quality assessment. We sought to identify those risk adjustment variables that affect the likelihood of success and complications. This article offers the rationale for different clinical and technical considerations that may be important during the design of clinical trials for endovascular treatment of cerebral aneurysms. Included in this guidance article are suggestions for uniform reporting standards for such trials. These definitions and standards are primarily intended for research purposes; however, they should also be helpful in clinical practice and applicable to all publications.

CONCLUSIONS

The evaluation and treatment of brain aneurysms often involve multiple medical specialties. Recent reviews by the American Heart Association have surveyed the medical literature to develop guidelines for the clinical management of ruptured and unruptured cerebral aneurysms. Despite efforts to synthesize existing knowledge on cerebral aneurysm evaluation and treatment, significant inconsistencies remain in nomenclature and definition for research and reporting purposes. These operational definitions were selected by consensus of a multidisciplinary writing group to provide consistency for reporting on imaging in clinical trials and observational studies involving cerebral aneurysms. These definitions should help different groups to publish results that are directly comparable.

CONTROVERSIES IN THE ENDOVASCULAR MANAGEMENT OF CEREBRAL VASOSPASM AFTER INTRACRANIAL ANEURYSM RUPTURE AND FUTURE DIRECTIONS FOR THERAPEUTIC APPROACHES

CEREBRAL VASOSPASM IS one of the leading causes of morbidity and mortality after aneurysmal subarachnoid hemorrhage. Despite maximal medical therapy, however, up to 15% of patients surviving the ictus of subarachnoid hemorrhage experience stroke or death from vasospasm. For those cases of vasospasm that are refractory to medical treatment, endovascular techniques are frequently used, including balloon angioplasty with or without intra-arterial infusion of vasodilators, combined endovascular modalities, and aortic balloon devices. In this article, we review each of these therapies and their expanding role in the management of this condition. Moving forward, rigorous prospective outcome assessments after endovascular treatment of cerebral vasospasm are necessary to clearly delineate the efficacy and indications for these techniques.

Carotid stenosis in a multiethnic population

BACKGROUND

Carotid stenosis is an important, treatable cause of stroke. Several population-based studies have shown ethnic differences in the prevalence of carotid atherosclerosis. This study was performed at a large multiethnic hospital to clarify these differences.

METHODS

One thousand six carotid artery ultrasounds performed by the Department of Radiology at Los Angeles County General Hospital over a 4-year period were reviewed. Patients were classified as Caucasian (n=151), Hispanic (n=515), Black (n=173), or Asian (n=167) by self-declaration and birthplace. Carotid stenosis was defined as mild (1% to 39%), moderate (40% to 59%), severe (60% to 79%), critical (80% to 99%), or total (100%).

RESULTS

Twenty and one-half percent of Caucasian patients had greater than 59% stenosis compared with 10.1% of Hispanics, 8.7% of Blacks, and 10.7% of Asians (P<0.001). Nine and two-tenths percent of Caucasians had greater than 79% stenosis compared with 4.3% of Hispanics, 2.9% of Blacks, and 2.8% of Asians (P<0.001). There were no significant differences in age or gender representations between ethnic groups, and the indications for ordering carotid duplex sonography also did not vary by race. Caucasians and Blacks had a higher prevalence of cardiac disease, smoking, and heavy alcohol abuse. Hispanics had higher rates of diabetes.

CONCLUSIONS

These results indicate that significant differences in the degree of carotid stenosis exist among ethnic groups. Caucasian patients in our series showed a statistically higher likelihood of having a severe or critical level of stenosis. These findings may have implications for the allocation of health care resources as ethnic minorities compose a greater proportion of the population.

AUGMENTATION OF CEREBRAL BLOOD FLOW AND REVERSAL OF ENDOTHELIN-1-INDUCED VASOSPASM

OBJECTIVE

Local intra-arterial infusions of verapamil and nicardipine have been used to treat human cerebral vasospasm. Only a few reports of early clinical experience with these medications are currently available, and limited data are available regarding their cerebral physiological activity. We assessed the efficacy of intracarotid administration of verapamil and nicardipine on augmenting cerebral blood flow of New Zealand White rabbits and compared the ability of these drugs with reverse topical endothelin (ET)-1-triggered vasospasm.

METHODS

In the first group of New Zealand white rabbits, cerebral blood flow (laser Doppler) and systemic hemodynamic measurements were recorded at baseline and with increasing intracarotid doses of verapamil and nicardipine. In the second group, topical ET-1 (10(-4) mol/L) was applied in an acutely implanted cranial window. Dose responses to nonspecific reversal of ET-1-induced vasospasm were evaluated with intra-arterially administered nicardipine and verapamil.

RESULTS

The dose-response studies revealed that intracarotid administration of nicardipine, compared with verapamil, was more effective in augmenting cerebral blood flow. Topical ET-1-induced vasospasm was completely reversed by nicardipine and partially reversed by verapamil.

CONCLUSION

This study suggests that intra-arterially administered nicardipine is a more potent cerebral vasodilator and is superior to verapamil for treating ET-1-induced experimental cerebral vasospasm and supports further investigation of these agents in subarachnoid hemorrhage-induced vasospasm.