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.

Imaging of Subdural Hematomas.

The imaging of subdural hematoma has evolved significantly. Computed tomography and MRI have supplanted other procedures and rendered most obsolete for the evaluation of intracranial pathology because of ease of use, tremendous soft tissue resolution, safety, and availability. Noncontrast computed tomography has become the accepted standard of care for the initial evaluation of patients with suspected subdural hematoma because of widespread availability, rapid acquisition time, and noninvasive nature. MRI offers important features in determining potential secondary causes of subdural hematoma, such as dural-based neoplasms.

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.

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.

Number and location of draining veins in pediatric arteriovenous malformations: association with hemorrhage.

OBJECT: The significance of draining vein anatomy is poorly defined in pediatric arteriovenous malformations (AVMs). In adult cohorts, the presence of fewer veins has been shown to lead to an increased rate of hemorrhage, but this phenomenon has not yet been studied in pediatric AVMs. This report analyzes the impact of draining vein anatomy on presentation and outcome in a large series of pediatric AVMs. METHODS: Eighty-five pediatric patients with AVMs were treated at the Columbia University Medical Center between 1991 and 2012. Charts were retrospectively reviewed for patient characteristics, clinical course, neurological outcome, and AVM angioarchitectural features identified on the angiogram performed at presentation. Univariate analyses were performed using chi-square test and ANOVA when appropriate; multivariate analysis was performed using logistic regression. RESULTS: Four patients were excluded due to incomplete records. Twenty-seven patients had 2 or 3 draining veins; 12 (44.4%) of these patients suffered from hemorrhage prior to surgery. Fifty-four patients had 1 draining vein; 39 (72.2%) of these 54 suffered from hemorrhage. Independent predictors of hemorrhage included the presence of a single draining vein (p = 0.04) and deep venous drainage (p = 0.02). Good outcome (modified Rankin Scale [mRS] score < 3) on discharge was found to be associated with higher admission Glasgow Coma Scale (GCS) scores (p = 0.0001, OR 0.638, 95% CI 0.40-0.93). Poor outcome (mRS score > 2) on discharge was found to be associated with deep venous drainage (p = 0.04, OR 4.68, 95% CI 1.1-19.98). A higher admission GCS score was associated with a lower discharge mRS score (p = 0.0003, OR 0.6, 95% CI 0.46-0.79), and the presence of a single draining vein was associated with a lower mRS score on long-term follow-up (p = 0.04, OR 0.18, 95% CI 0.032-0.99). CONCLUSIONS: The authors' data suggest that the presence of a single draining vein or deep venous drainage plays a role in hemorrhage risk and ultimate outcome in pediatric AVMs. Small AVMs with a single or deep draining vein may have the highest risk of hemorrhage.

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.

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.

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.

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.

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.

Training in endovascular surgical neuroradiology.

BACKGROUND: During the past few years, the field of endovascular surgical neuroradiology has been expanding. Neurosurgeons, radiologists, and neurologists are currently being trained. We analyzed data from a national survey of endovascular training programs to assess the current training status and future projections. METHODS: Survey participation requests were sent out to program directors and members of the Society of Endovascular Neurosurgery, the Society of Neurointerventional Surgery, and the Society of Vascular and Interventional Neurology. The format was an on-line survey designed by the authors, and completed through the SurveyMonkey.com website. Forty-three programs were identified and invited to participate. RESULTS: We achieved a response rate of 81% (n = 35). Twenty-seven (79%) of the 35 respondents listed their training program as academic, and 7 (20%) listed it as a mixture of academic with private practice. The training program faculty consisted of 57 radiologists, 39 neurosurgeons, and 10 neurologists. Length of fellowship offered was the same for all specialties in 43%, and differed based on clinical experience/background in 51%. Of the programs, 86% offered a 2-year fellowship, 49% had a mandatory resident rotation, 17% offered an infolded complete fellowship for residents, and 34% offered an infolded partial fellowship. Only 9% reported no resident exposure at all. There were 12% of respondents who reported to have knowledge of vascular surgeons or cardiologists performing intracranial procedures. At the time of the survey, there were 68 fellows in training, and most entered training immediately after residency (38%), whereas 26% entered after a fellowship and another 26% trained while in residency. There will be a 14% increase of graduates within the next 5 years. Comparing the past 5 years (2003-2007) with future 5-year projections (2008-2012), the number of radiologists is declining by 37% (73 vs. 46), whereas the number of neurosurgeons (74 vs. 106) and neurologists (20 vs. 37) is increasing by 42.5% and 112%, respectively. CONCLUSIONS: This survey suggests that there is a strong interest in endovascular surgical neuroradiology. The overall number of graduates is increasing, particularly in neurosurgery and neurology. Although the majority of current faculty is still comprised of neuroradiologists, the number of graduates in radiology will be decreasing during the next 5 years, reflecting a trend toward greater subspecialization within the fields of neurosurgery and neurology. Peer-Review Article.

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.

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 Neurolnterventional Surgery, Society of Interventional Radiology; Joint Section on Cerebro-vascular 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.

Endovascular treatment of intracranial arteriovenous malformation.

Arteriovenous malformations (AVMs) of the brain are vascular lesions in which an abnormal tangle or nidus of vessels permits pathologic shunting of blood flow from the arterial to the venous tree without an intervening capillary bed. With brain imaging techniques, an increasing number of AVMs are detected before they hemorrhage, leading to new considerations and modifications of interdisciplinary management strategies. Treatment options include endovascular embolization, microsurgical resection, radiosurgery, medical management, or a combination of these. Neuroendovascular therapy is a critical component of this multidisciplinary and multimodal approach. The development and introduction of newer techniques and agents will continue to affect embolization treatments.

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 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.