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Tan G, Huguenard AL, Donovan KM, Demarest P, Liu X, Li Z, Adamek M, Lavine K, Vellimana AK, Kummer TT, Osbun JW, Zipfel GJ, Brunner P, Leuthardt EC. The effect of transcutaneous auricular vagus nerve stimulation on cardiovascular function in subarachnoid hemorrhage patients: a safety study. medRxiv 2024:2024.04.03.24304759. [PMID: 38633771 PMCID: PMC11023641 DOI: 10.1101/2024.04.03.24304759] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/19/2024]
Abstract
Objective Subarachnoid hemorrhage (SAH) is characterized by intense central inflammation, leading to substantial post-hemorrhagic complications such as vasospasm and delayed cerebral ischemia.2,6,7 Given the anti-inflammatory effect of transcutaneous auricular vagus nerve stimulation (taVNS) and its ability to promote brain plasticity, taVNS has emerged as a promising therapeutic option for SAH patients.3,8,9 However, the effects of taVNS on cardiovascular dynamics in critically ill patients like those with SAH have not yet been investigated. Given the association between cardiac complications and elevated risk of poor clinical outcomes after SAH, it is essential to characterize the cardiovascular effects of taVNS to ensure this approach is safe in this fragile population4. Therefore, we assessed the impact of both acute taVNS and repetitive taVNS on cardiovascular function in this study. Methods In this randomized clinical trial, 24 SAH patients were assigned to either a taVNS treatment or a Sham treatment group. During their stay in the intensive care unit, we monitored patient electrocardiogram (ECG) readings and vital signs. We compared long-term changes in heart rate, heart rate variability, QT interval, and blood pressure between the two groups. Additionally, we assessed the effects of acute taVNS by comparing cardiovascular metrics before, during, and after the intervention. We also explored rapidly responsive cardiovascular biomarkers in patients exhibiting clinical improvement. Results We found that repetitive taVNS did not significantly alter heart rate, corrected QT interval, blood pressure, or intracranial pressure. However, taVNS increased overall heart rate variability and parasympathetic activity from 5-10 days after initial treatment, as compared to the sham treatment. Acutely, taVNS increased heart rate, blood pressure, and peripheral perfusion index without affecting the corrected QT interval, intracranial pressure, or heart rate variability. The acute post-treatment elevation in heart rate was more pronounced in patients who experienced a decrease of more than 1 point in their Modified Rankin Score at the time of discharge. Conclusions Our study found that taVNS treatment did not induce adverse cardiovascular effects, such as bradycardia or QT prolongation, supporting its development as a safe immunomodulatory treatment approach for SAH patients. The observed acute increase in heart rate after taVNS treatment may serve as a biomarker for SAH patients who could derive greater benefit from this treatment.
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Affiliation(s)
- Gansheng Tan
- Department of Neurosurgery, Washington University School of Medicine, St. Louis, MO, USA
- Department of Biomedical Engineering, Washington University in St. Louis, MO, USA
| | - Anna L. Huguenard
- Department of Neurosurgery, Washington University School of Medicine, St. Louis, MO, USA
| | - Kara M. Donovan
- Department of Neurosurgery, Washington University School of Medicine, St. Louis, MO, USA
- Department of Biomedical Engineering, Washington University in St. Louis, MO, USA
| | - Phillip Demarest
- Department of Neurosurgery, Washington University School of Medicine, St. Louis, MO, USA
- Department of Biomedical Engineering, Washington University in St. Louis, MO, USA
| | - Xiaoxuan Liu
- Department of Neurosurgery, Washington University School of Medicine, St. Louis, MO, USA
- Department of Biomedical Engineering, Washington University in St. Louis, MO, USA
| | - Ziwei Li
- Department of Neurosurgery, Washington University School of Medicine, St. Louis, MO, USA
- Department of Biomedical Engineering, Washington University in St. Louis, MO, USA
| | - Markus Adamek
- Department of Neuroscience, Washington University in St. Louis, MO, USA
| | - Kory Lavine
- Department of Neurosurgery, Washington University School of Medicine, St. Louis, MO, USA
| | - Ananth K. Vellimana
- Department of Neurosurgery, Washington University School of Medicine, St. Louis, MO, USA
- Department of Neurology, Washington University in St. Louis, MO, USA
| | | | - Joshua W. Osbun
- Department of Neurosurgery, Washington University School of Medicine, St. Louis, MO, USA
- Department of Neurology, Washington University in St. Louis, MO, USA
| | - Gregory J. Zipfel
- Department of Neurosurgery, Washington University School of Medicine, St. Louis, MO, USA
| | - Peter Brunner
- Department of Neurosurgery, Washington University School of Medicine, St. Louis, MO, USA
- Department of Biomedical Engineering, Washington University in St. Louis, MO, USA
| | - Eric C. Leuthardt
- Department of Neurosurgery, Washington University School of Medicine, St. Louis, MO, USA
- Department of Biomedical Engineering, Washington University in St. Louis, MO, USA
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Huguenard AL, Tan G, Johnson GW, Adamek M, Coxon AT, Kummer TT, Osbun JW, Vellimana AK, Limbrick DD, Zipfel GJ, Brunner P, Leuthardt EC. Non-invasive Auricular Vagus nerve stimulation for Subarachnoid Hemorrhage (NAVSaH): Protocol for a prospective, triple-blinded, randomized controlled trial. medRxiv 2024:2024.03.18.24304239. [PMID: 38562875 PMCID: PMC10984059 DOI: 10.1101/2024.03.18.24304239] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
Background Inflammation has been implicated in driving the morbidity associated with subarachnoid hemorrhage (SAH). Despite understanding the important role of inflammation in morbidity following SAH, there is no current effective way to modulate this deleterious response. There is a critical need for a novel approach to immunomodulation that can be safely, rapidly, and effectively deployed in SAH patients. Vagus nerve stimulation (VNS) provides a non-pharmacologic approach to immunomodulation, with prior studies demonstrating VNS can reduce systemic inflammatory markers, and VNS has had early success treating inflammatory conditions such as arthritis, sepsis, and inflammatory bowel diseases. The aim of the Non-invasive Auricular Vagus nerve stimulation for Subarachnoid Hemorrhage (NAVSaH) trial is to translate the use of non-invasive transcutaneous auricular VNS (taVNS) to spontaneous SAH, with our central hypothesis being that implementing taVNS in the acute period following spontaneous SAH attenuates the expected inflammatory response to hemorrhage and curtails morbidity associated with inflammatory-mediated clinical endpoints. Materials and methods The overall objectives for the NAHSaH trial are to 1) Define the impact that taVNS has on SAH-induced inflammatory markers in the plasma and cerebrospinal fluid (CSF), 2) Determine whether taVNS following SAH reduces radiographic vasospasm, and 3) Determine whether taVNS following SAH reduces chronic hydrocephalus. Following presentation to a single enrollment site, enrolled SAH patients are randomly assigned twice daily treatment with either taVNS or sham stimulation for the duration of their intensive care unit stay. Blood and CSF are drawn before initiation of treatment sessions, and then every three days during a patient's hospital stay. Primary endpoints include change in the inflammatory cytokine TNF-α in plasma and cerebrospinal fluid between day 1 and day 13, rate of radiographic vasospasm, and rate of requirement for long-term CSF diversion via a ventricular shunt. Secondary outcomes include exploratory analyses of a panel of additional cytokines, number and type of hospitalized acquired infections, duration of external ventricular drain in days, interventions required for vasospasm, continuous physiology data before, during, and after treatment sessions, hospital length of stay, intensive care unit length of stay, and modified Rankin Scale score (mRS) at admission, discharge, and each at follow-up appointment for up to two years following SAH. Discussion Inflammation plays a central role in morbidity following SAH. This NAVSaH trial is innovative because it diverges from the pharmacologic status quo by harnessing a novel non-invasive neuromodulatory approach and its known anti-inflammatory effects to alter the pathophysiology of SAH. The investigation of a new, effective, and rapidly deployable intervention in SAH offers a new route to improve outcomes following SAH. Trial registration Clinical Trials Registered, NCT04557618. Registered on September 21, 2020, and the first patient was enrolled on January 4, 2021.
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Affiliation(s)
- Anna L Huguenard
- Department of Neurosurgery, Washington University in St. Louis, St. Louis, Missouri, USA
| | - Gansheng Tan
- Department Biomedical Engineering, Washington University in St. Louis, St. Louis, Missouri, USA
| | - Gabrielle W Johnson
- Department of Neurosurgery, Washington University in St. Louis, St. Louis, Missouri, USA
| | - Markus Adamek
- Department of Neuroscience, Washington University in St. Louis, St. Louis, Missouri, USA
| | - Andrew T Coxon
- Department of Neurosurgery, Washington University in St. Louis, St. Louis, Missouri, USA
| | - Terrance T Kummer
- Department of Neurology, Washington University in St. Louis, St. Louis, Missouri, USA
| | - Joshua W Osbun
- Department of Neurosurgery, Washington University in St. Louis, St. Louis, Missouri, USA
| | - Ananth K Vellimana
- Department of Neurosurgery, Washington University in St. Louis, St. Louis, Missouri, USA
| | - David D. Limbrick
- Department of Neurosurgery, Washington University in St. Louis, St. Louis, Missouri, USA
| | - Gregory J Zipfel
- Department of Neurosurgery, Washington University in St. Louis, St. Louis, Missouri, USA
| | - Peter Brunner
- Department of Neurosurgery, Washington University in St. Louis, St. Louis, Missouri, USA
- Department Biomedical Engineering, Washington University in St. Louis, St. Louis, Missouri, USA
| | - Eric C Leuthardt
- Department of Neurosurgery, Washington University in St. Louis, St. Louis, Missouri, USA
- Department Biomedical Engineering, Washington University in St. Louis, St. Louis, Missouri, USA
- Department of Neuroscience, Washington University in St. Louis, St. Louis, Missouri, USA
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3
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Samudralwar RD, Bailey TC, Vellimana AK, Wright NM, Clifford DB. Mycobacterium haemophilum Related Myelitis in Geographically Linked Cases. Ann Neurol 2024; 95:614-616. [PMID: 37953637 DOI: 10.1002/ana.26828] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2023] [Revised: 10/25/2023] [Accepted: 10/30/2023] [Indexed: 11/14/2023]
Affiliation(s)
- Rohini D Samudralwar
- Division of Multiple Sclerosis and Related Neuroinflammatory Disorders, Department of Neurology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Thomas C Bailey
- Division of Infectious Diseases, Department of Medicine, Washington University School of Medicine, St Louis, Missouri, USA
| | - Ananth K Vellimana
- Department of Neurosurgery, Washington University School of Medicine, St Louis, Missouri, USA
| | | | - David B Clifford
- Department of Neurology, Washington University School of Medicine, St Louis, Missouri, USA
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Lauzier DC, Cler SJ, Chatterjee AR, Osbun JW, Vellimana AK, Derdeyn CP, Cross DT, Moran CJ, Kansagra AP. In-hospital imaging utilization after elective endovascular brain aneurysm treatment: a surrogate metric for the value of hospitalization. J Neurosurg 2024; 140:430-435. [PMID: 37548550 DOI: 10.3171/2023.5.jns23656] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Accepted: 05/30/2023] [Indexed: 08/08/2023]
Abstract
OBJECTIVE Despite the adoption of same-day outpatient surgical procedures in some specialties, it remains common practice to admit patients for monitoring after elective endovascular treatment of brain aneurysms to monitor for complications. The necessity of such monitoring has not been fully characterized. Here, the authors reviewed the utilization of imaging during posttreatment hospitalization, a surrogate measure for workup of suspected complications requiring hospital resources, to infer the value of inpatient monitoring after endovascular aneurysm treatment. METHODS Clinical and angiographic data from eligible patients were retrospectively assessed for demographic characteristics, imaging indications, timing of imaging, and imaging findings. Patients were included if they underwent elective endovascular brain aneurysm treatment, and patients were excluded if significant intraprocedural complications occurred. The recorded imaging modalities included CT, MRI, catheter-based imaging, and ultrasound; plain radiographs were excluded. Multivariable logistic regression analysis was performed to identify predictors of the need for posttreatment imaging. RESULTS In total, 1229 elective endovascular procedures for brain aneurysm treatment were included. Patients underwent imaging before discharge in 13.4% (165/1229) of cases, with significant findings in 5.0% (61/1229) of cases. The median (interquartile range) time to first posttreatment imaging was 13.2 (4.2-22.8) hours. The need for imaging during posttreatment hospitalization was positively associated with larger aneurysm size (p < 0.05) and negatively associated with underlying cardiovascular disease (p < 0.05). CONCLUSIONS More than 1 in 8 patients who underwent elective endovascular brain aneurysm treatment required imaging during posttreatment hospitalization, most within the first 24 hours, and 1 in 20 had significant findings. These results suggest the importance of short-term hospitalization after elective endovascular aneurysm treatment.
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Affiliation(s)
- David C Lauzier
- 1Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, Missouri
| | - Samuel J Cler
- 1Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, Missouri
| | - Arindam R Chatterjee
- 1Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, Missouri
- 3Neurology, Washington University School of Medicine, St. Louis, Missouri
| | - Joshua W Osbun
- 1Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, Missouri
- 3Neurology, Washington University School of Medicine, St. Louis, Missouri
| | - Ananth K Vellimana
- 1Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, Missouri
- 3Neurology, Washington University School of Medicine, St. Louis, Missouri
| | - Colin P Derdeyn
- 4Department of Radiology, University of Iowa School of Medicine, Iowa City, Iowa; and
| | - Dewitte T Cross
- 1Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, Missouri
| | - Christopher J Moran
- 1Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, Missouri
- Departments of2Neurological Surgery and
| | - Akash P Kansagra
- 1Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, Missouri
- 3Neurology, Washington University School of Medicine, St. Louis, Missouri
- 5Department of Neurointerventional Surgery, California Center for Neurointerventional Surgery, San Diego, California
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5
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Lauzier DC, Srienc AI, Vellimana AK, Dacey Jr RG, Zipfel GJ. Peripheral macrophages in the development and progression of structural cerebrovascular pathologies. J Cereb Blood Flow Metab 2024; 44:169-191. [PMID: 38000039 PMCID: PMC10993883 DOI: 10.1177/0271678x231217001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/05/2023] [Revised: 09/10/2023] [Accepted: 09/15/2023] [Indexed: 11/26/2023]
Abstract
The human cerebrovascular system is responsible for maintaining neural function through oxygenation, nutrient supply, filtration of toxins, and additional specialized tasks. While the cerebrovascular system has resilience imparted by elaborate redundant collateral circulation from supportive tertiary structures, it is not infallible, and is susceptible to developing structural vascular abnormalities. The causes of this class of structural cerebrovascular diseases can be broadly categorized as 1) intrinsic developmental diseases resulting from genetic or other underlying aberrations (arteriovenous malformations and cavernous malformations) or 2) extrinsic acquired diseases that cause compensatory mechanisms to drive vascular remodeling (aneurysms and arteriovenous fistulae). Cerebrovascular diseases of both types pose significant risks to patients, in some cases leading to death or disability. The drivers of such diseases are extensive, yet inflammation is intimately tied to all of their progressions. Central to this inflammatory hypothesis is the role of peripheral macrophages; targeting this critical cell type may lead to diagnostic and therapeutic advancement in this area. Here, we comprehensively review the role that peripheral macrophages play in cerebrovascular pathogenesis, provide a schema through which macrophage behavior can be understood in cerebrovascular pathologies, and describe emerging diagnostic and therapeutic avenues in this area.
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Affiliation(s)
- David C Lauzier
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, MO, USA
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO, USA
| | - Anja I Srienc
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, MO, USA
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO, USA
| | - Ananth K Vellimana
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, MO, USA
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO, USA
- Department of Neurology, Washington University School of Medicine, St. Louis, MO, USA
| | - Ralph G Dacey Jr
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, MO, USA
| | - Gregory J Zipfel
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, MO, USA
- Department of Neurology, Washington University School of Medicine, St. Louis, MO, USA
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6
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Lauzier DC, Cler SJ, Srienc AI, Patel B, Pierce A, Gagne J, Vellimana AK, Chatterjee AR, Kansagra AP, Moran CJ, Zipfel GJ, Osbun JW. Comparative cost analysis of endovascular and open approaches for elective treatment of middle cerebral artery aneurysms. Interv Neuroradiol 2023:15910199231221298. [PMID: 38105434 DOI: 10.1177/15910199231221298] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2023] Open
Abstract
BACKGROUND Intracranial aneurysms of the middle cerebral artery can be treated using several open surgical and endovascular approaches. Given the growing evidence of clinical equipoise between these various treatment strategies, there is a need to assess the costs associated with each. METHODS Cost of aneurysm treatment was divided into two categories for comparison. "Initial cost" comprised the total in-hospital expenses for initial aneurysm treatment and "total cost" comprised initial aneurysm treatment and all expenses relating to readmission due to treatment-related complications, prescribed catheter angiograms for monitoring of treatment stability, and any retreatments needed for a given aneurysm. The open surgical group was subdivided into a pterional approach group and a lateral supraorbital (LSO) approach group for. RESULTS Median initial cost was $37,152 (IQR $31,318-$44,947) for aneurysms treated with the pterional approach, $29,452 (IQR $27,779-$32,826) for aneurysms treated with the LSO approach, and $19,587 (IQR $14,125-$30,521) for aneurysms treated with endovascular approaches. The median total cost was $39,737 (IQR $33,891-$62,259) for aneurysms treated with the pterional approach, $31,785 (IQR $29,513-$41,099) for aneurysms treated with the LSO approach, and $24,578 (IQR $18,977-$34,547) for aneurysms treated with endovascular approaches. Analysis of variance test demonstrated variance across groups for both initial and total cost (p = 0.004, p = 0.008, respectively). In our subsequent analysis, initial cost and total cost were higher in the pterional group than the endovascular group (p = 0.003 and p = 0.006, respectively). CONCLUSIONS Endovascular treatment of elective aneurysms has a significantly lower cost than open surgical treatment with the pterional approach, but not with the LSO approach. For aneurysms not amenable to endovascular treatment, a minimally invasive LSO approach carries a lower cost burden than a pterional approach.
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Affiliation(s)
- David C Lauzier
- Department of Neurological Surgery, Washington University in St Louis School of Medicine, St Louis, MO, USA
- Mallinckrodt Institute of Radiology, Washington University in St Louis School of Medicine, St Louis, MO, USA
| | - Samuel J Cler
- Department of Neurological Surgery, Washington University in St Louis School of Medicine, St Louis, MO, USA
- Mallinckrodt Institute of Radiology, Washington University in St Louis School of Medicine, St Louis, MO, USA
| | - Anja I Srienc
- Department of Neurological Surgery, Washington University in St Louis School of Medicine, St Louis, MO, USA
- Mallinckrodt Institute of Radiology, Washington University in St Louis School of Medicine, St Louis, MO, USA
| | - Bhuvic Patel
- Department of Neurological Surgery, Washington University in St Louis School of Medicine, St Louis, MO, USA
| | - Andrew Pierce
- Barnes Jewish Hospital Clinical Operations, St Louis, MO, USA
| | - Jason Gagne
- Barnes Jewish Hospital Clinical Operations, St Louis, MO, USA
| | - Ananth K Vellimana
- Department of Neurological Surgery, Washington University in St Louis School of Medicine, St Louis, MO, USA
- Mallinckrodt Institute of Radiology, Washington University in St Louis School of Medicine, St Louis, MO, USA
- Department of Neurology, Washington University in St Louis School of Medicine, St Louis, MO, USA
| | - Arindam R Chatterjee
- Department of Neurological Surgery, Washington University in St Louis School of Medicine, St Louis, MO, USA
- Mallinckrodt Institute of Radiology, Washington University in St Louis School of Medicine, St Louis, MO, USA
- Department of Neurology, Washington University in St Louis School of Medicine, St Louis, MO, USA
| | - Akash P Kansagra
- Department of Neurointerventional Surgery, California Center for Neurointerventional Surgery, St Louis, MO, USA
| | - Christopher J Moran
- Department of Neurological Surgery, Washington University in St Louis School of Medicine, St Louis, MO, USA
- Mallinckrodt Institute of Radiology, Washington University in St Louis School of Medicine, St Louis, MO, USA
| | - Gregory J Zipfel
- Department of Neurological Surgery, Washington University in St Louis School of Medicine, St Louis, MO, USA
- Department of Neurology, Washington University in St Louis School of Medicine, St Louis, MO, USA
| | - Joshua W Osbun
- Department of Neurological Surgery, Washington University in St Louis School of Medicine, St Louis, MO, USA
- Mallinckrodt Institute of Radiology, Washington University in St Louis School of Medicine, St Louis, MO, USA
- Department of Neurology, Washington University in St Louis School of Medicine, St Louis, MO, USA
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Liu M, Jayaraman K, Nelson JW, Mehla J, Diwan D, Vellimana AK, Zipfel GJ, Athiraman U. Propofol Affords No Protection against Delayed Cerebral Ischemia in a Mouse Model of Subarachnoid Hemorrhage. Diseases 2023; 11:130. [PMID: 37873774 PMCID: PMC10594442 DOI: 10.3390/diseases11040130] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Revised: 09/24/2023] [Accepted: 09/26/2023] [Indexed: 10/25/2023] Open
Abstract
Delayed cerebral ischemia (DCI) is an important contributor to poor outcomes in aneurysmal subarachnoid hemorrhage (SAH) patients. We previously showed that volatile anesthetics such as isoflurane, sevoflurane and desflurane provided robust protection against SAH-induced DCI, but the impact of a more commonly used intravenous anesthetic agent, propofol, is not known. The goal of our current study is to examine the neurovascular protective effects of propofol on SAH-induced DCI. Twelve-week-old male wild-type mice were utilized for the study. Mice underwent endovascular perforation SAH or sham surgery followed one hour later by propofol infusion through the internal jugular vein (2 mg/kg/min continuous intravenous infusion). Large artery vasospasm was assessed three days after SAH. Neurological outcome assessment was performed at baseline and then daily until animal sacrifice. Statistical analysis was performed via one-way ANOVA and two-way repeated measures ANOVA followed by the Newman-Keuls multiple comparison test with significance set at p < 0.05. Intravenous propofol did not provide any protection against large artery vasospasm or sensory-motor neurological deficits induced by SAH. Our data show that propofol did not afford significant protection against SAH-induced DCI. These results are consistent with recent clinical studies that suggest that the neurovascular protection afforded by anesthetic conditioning is critically dependent on the class of anesthetic agent.
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Affiliation(s)
- Meizi Liu
- Molecular Cell Biology, Washington University, St. Louis, MO 63110, USA
| | - Keshav Jayaraman
- Department of Neurological Surgery, Washington University, St. Louis, MO 63110, USA
| | - James W. Nelson
- Department of Neurological Surgery, Washington University, St. Louis, MO 63110, USA
| | - Jogender Mehla
- Department of Neurological Surgery, Washington University, St. Louis, MO 63110, USA
| | - Deepti Diwan
- Department of Neurological Surgery, Washington University, St. Louis, MO 63110, USA
| | - Ananth K. Vellimana
- Department of Neurological Surgery, Washington University, St. Louis, MO 63110, USA
- Department of Radiology, Washington University, St. Louis, MO 63110, USA
- Department of Neurology, Washington University, St. Louis, MO 63110, USA
| | - Gregory J. Zipfel
- Department of Neurological Surgery, Washington University, St. Louis, MO 63110, USA
- Department of Neurology, Washington University, St. Louis, MO 63110, USA
| | - Umeshkumar Athiraman
- Department of Anesthesiology, Washington University, Campus Box 8054, 660 South Euclid Avenue, St. Louis, MO 63110, USA
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Coxon AT, Desai R, Patel PR, Vellimana AK, Willie JT, Dowling JL, Leuthardt EC, Kim AH, Johanns TM, Siegel BA, Dunn GP. A pilot study of lymphoscintigraphy with tracer injection into the human brain. J Cereb Blood Flow Metab 2023; 43:1382-1389. [PMID: 36994857 PMCID: PMC10369147 DOI: 10.1177/0271678x231160891] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/12/2022] [Revised: 01/08/2023] [Accepted: 01/14/2023] [Indexed: 03/31/2023]
Abstract
Many groups have reported lymphatic and glymphatic structures in animal and human brains, but tracer injection into the human brain to demonstrate real-time lymphatic drainage and mapping has not been described. We enrolled patients undergoing standard-of-care resection or stereotactic biopsy for suspected intracranial tumors. Patients received peritumoral injections of 99mTc-tilmanocept followed by planar or tomographic imaging. Fourteen patients with suspected brain tumors were enrolled. One was excluded from analysis because of tracer leakage during injection. There was no drainage of 99mTc-tilmanocept to regional lymph nodes in any of the patients. On average, after correcting for radioactive decay, 70.7% (95% CI: 59.9%, 81.6%) of the tracer in the injection site and 78.1% (95% CI: 71.1%, 85.1%) in the whole-head on the day of surgery remained the morning after, with variable radioactivity in the subarachnoid space. The retained fraction was much greater than expected based on the clearance rate from non-brain injection sites. In this pilot study, the lymphatic tracer 99mTc-tilmanocept was injected into the brain parenchyma, and there was no drainage outside the brain to the cervical lymph nodes. Our work demonstrates an inefficiency of drainage from peritumoral brain parenchyma and highlights a therapeutic opportunity to improve immunosurveillance of the brain.
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Affiliation(s)
- Andrew T Coxon
- Washington University School of Medicine, St. Louis, MO, USA
| | - Rupen Desai
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, MO, USA
| | - Pujan R Patel
- Washington University School of Medicine, St. Louis, MO, USA
| | - Ananth K Vellimana
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, MO, USA
| | - Jon T Willie
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, MO, USA
| | - Joshua L Dowling
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, MO, USA
- Alvin J. Siteman Cancer Center, Washington University School of Medicine, St. Louis, MO, USA
| | - Eric C Leuthardt
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, MO, USA
- Alvin J. Siteman Cancer Center, Washington University School of Medicine, St. Louis, MO, USA
| | - Albert H Kim
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, MO, USA
- Alvin J. Siteman Cancer Center, Washington University School of Medicine, St. Louis, MO, USA
| | - Tanner M Johanns
- Alvin J. Siteman Cancer Center, Washington University School of Medicine, St. Louis, MO, USA
- Division of Medical Oncology, Washington University School of Medicine, St. Louis, MO, USA
| | - Barry A Siegel
- Alvin J. Siteman Cancer Center, Washington University School of Medicine, St. Louis, MO, USA
- Division of Nuclear Medicine, Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO, USA
| | - Gavin P Dunn
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, MO, USA
- Alvin J. Siteman Cancer Center, Washington University School of Medicine, St. Louis, MO, USA
- Current address: Department of Neurosurgery, Massachusetts General Hospital, Boston, MA, USA
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Lauzier DC, Jayaraman K, Yuan JY, Diwan D, Vellimana AK, Osbun J, Chatterjee AR, Athiraman U, Dhar R, Zipfel GJ. Early Brain Injury After Subarachnoid Hemorrhage: Incidence and Mechanisms. Stroke 2023; 54:1426-1440. [PMID: 36866673 PMCID: PMC10243167 DOI: 10.1161/strokeaha.122.040072] [Citation(s) in RCA: 17] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/04/2023]
Abstract
Aneurysmal subarachnoid hemorrhage is a devastating condition causing significant morbidity and mortality. While outcomes from subarachnoid hemorrhage have improved in recent years, there continues to be significant interest in identifying therapeutic targets for this disease. In particular, there has been a shift in emphasis toward secondary brain injury that develops in the first 72 hours after subarachnoid hemorrhage. This time period of interest is referred to as the early brain injury period and comprises processes including microcirculatory dysfunction, blood-brain-barrier breakdown, neuroinflammation, cerebral edema, oxidative cascades, and neuronal death. Advances in our understanding of the mechanisms defining the early brain injury period have been accompanied by improved imaging and nonimaging biomarkers for identifying early brain injury, leading to the recognition of an elevated clinical incidence of early brain injury compared with prior estimates. With the frequency, impact, and mechanisms of early brain injury better defined, there is a need to review the literature in this area to guide preclinical and clinical study.
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Affiliation(s)
- David C. Lauzier
- Department of Neurological Surgery, Washington University School of Medicine
| | - Keshav Jayaraman
- Department of Neurological Surgery, Washington University School of Medicine
| | - Jane Y. Yuan
- Department of Neurological Surgery, Washington University School of Medicine
| | - Deepti Diwan
- Department of Neurological Surgery, Washington University School of Medicine
| | - Ananth K. Vellimana
- Department of Neurological Surgery, Washington University School of Medicine
- Department of Neurology, Washington University School of Medicine
- Mallinckrodt Institute of Radiology, Washington University School of Medicine
| | - Joshua Osbun
- Department of Neurological Surgery, Washington University School of Medicine
- Department of Neurology, Washington University School of Medicine
- Mallinckrodt Institute of Radiology, Washington University School of Medicine
| | - Arindam R. Chatterjee
- Department of Neurological Surgery, Washington University School of Medicine
- Department of Neurology, Washington University School of Medicine
- Mallinckrodt Institute of Radiology, Washington University School of Medicine
| | | | - Rajat Dhar
- Department of Neurology, Washington University School of Medicine
| | - Gregory J. Zipfel
- Department of Neurological Surgery, Washington University School of Medicine
- Department of Neurology, Washington University School of Medicine
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Liu M, Jayaraman K, Mehla J, Diwan D, Nelson JW, Hussein AE, Vellimana AK, Abu-Amer Y, Zipfel GJ, Athiraman U. Isoflurane Conditioning Provides Protection against Subarachnoid Hemorrhage Induced Delayed Cerebral Ischemia through NF-kB Inhibition. Biomedicines 2023; 11:biomedicines11041163. [PMID: 37189781 DOI: 10.3390/biomedicines11041163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2023] [Revised: 04/08/2023] [Accepted: 04/11/2023] [Indexed: 05/17/2023] Open
Abstract
Delayed cerebral ischemia (DCI) is the largest treatable cause of poor outcome after aneurysmal subarachnoid hemorrhage (SAH). Nuclear Factor Kappa-light-chain-enhancer of Activated B cells (NF-kB), a transcription factor known to function as a pivotal mediator of inflammation, is upregulated in SAH and is pathologically associated with vasospasm. We previously showed that a brief exposure to isoflurane, an inhalational anesthetic, provided multifaceted protection against DCI after SAH. The aim of our current study is to investigate the role of NF-kB in isoflurane-conditioning-induced neurovascular protection against SAH-induced DCI. Twelve-week-old wild type male mice (C57BL/6) were divided into five groups: sham, SAH, SAH + Pyrrolidine dithiocarbamate (PDTC, a selective NF-kB inhibitor), SAH + isoflurane conditioning, and SAH + PDTC with isoflurane conditioning. Experimental SAH was performed via endovascular perforation. Anesthetic conditioning was performed with isoflurane 2% for 1 h, 1 h after SAH. Three doses of PDTC (100 mg/kg) were injected intraperitoneally. NF-kB and microglial activation and the cellular source of NF-kB after SAH were assessed by immunofluorescence staining. Vasospasm, microvessel thrombosis, and neuroscore were assessed. NF-kB was activated after SAH; it was attenuated by isoflurane conditioning. Microglia was activated and found to be a major source of NF-kB expression after SAH. Isoflurane conditioning attenuated microglial activation and NF-kB expression in microglia after SAH. Isoflurane conditioning and PDTC individually attenuated large artery vasospasm and microvessel thrombosis, leading to improved neurological deficits after SAH. The addition of isoflurane to the PDTC group did not provide any additional DCI protection. These data indicate isoflurane-conditioning-induced DCI protection after SAH is mediated, at least in part, via downregulating the NF-kB pathway.
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Affiliation(s)
- Meizi Liu
- Department of Anesthesiology, Department of Neurosurgery, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Keshav Jayaraman
- Department of Anesthesiology, Department of Neurosurgery, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Jogender Mehla
- Department of Anesthesiology, Department of Neurosurgery, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Deepti Diwan
- Department of Anesthesiology, Department of Neurosurgery, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - James W Nelson
- Department of Anesthesiology, Department of Neurosurgery, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Ahmed E Hussein
- Department of Anesthesiology, Department of Neurosurgery, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Ananth K Vellimana
- Department of Anesthesiology, Department of Neurosurgery, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Yousef Abu-Amer
- Department of Orthopedic Surgery and Cell Biology & Physiology, Shriners Hospital for Children, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Gregory J Zipfel
- Department of Anesthesiology, Department of Neurosurgery, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Umeshkumar Athiraman
- Department of Anesthesiology, Department of Neurosurgery, Washington University in St. Louis, St. Louis, MO 63110, USA
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11
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Lauzier DC, Huguenard AL, Srienc AI, Cler SJ, Osbun JW, Chatterjee AR, Vellimana AK, Kansagra AP, Derdeyn CP, Cross DT, Moran CJ. A review of technological innovations leading to modern endovascular brain aneurysm treatment. Front Neurol 2023; 14:1156887. [PMID: 37114225 PMCID: PMC10126349 DOI: 10.3389/fneur.2023.1156887] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Accepted: 03/20/2023] [Indexed: 04/29/2023] Open
Abstract
Tools and techniques utilized in endovascular brain aneurysm treatment have undergone rapid evolution in recent decades. These technique and device-level innovations have allowed for treatment of highly complex intracranial aneurysms and improved patient outcomes. We review the major innovations within neurointervention that have led to the current state of brain aneurysm treatment.
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Affiliation(s)
- David C. Lauzier
- Mallinckrodt Institute of Radiology, Washington University in St. Louis School of Medicine, St. Louis, MO, United States
- Department of Neurological Surgery, Washington University in St. Louis School of Medicine, St. Louis, MO, United States
- *Correspondence: David C. Lauzier ;
| | - Anna L. Huguenard
- Mallinckrodt Institute of Radiology, Washington University in St. Louis School of Medicine, St. Louis, MO, United States
- Department of Neurological Surgery, Washington University in St. Louis School of Medicine, St. Louis, MO, United States
| | - Anja I. Srienc
- Mallinckrodt Institute of Radiology, Washington University in St. Louis School of Medicine, St. Louis, MO, United States
- Department of Neurological Surgery, Washington University in St. Louis School of Medicine, St. Louis, MO, United States
| | - Samuel J. Cler
- Mallinckrodt Institute of Radiology, Washington University in St. Louis School of Medicine, St. Louis, MO, United States
- Department of Neurology, Washington University in St. Louis School of Medicine, St. Louis, MO, United States
| | - Joshua W. Osbun
- Mallinckrodt Institute of Radiology, Washington University in St. Louis School of Medicine, St. Louis, MO, United States
- Department of Neurological Surgery, Washington University in St. Louis School of Medicine, St. Louis, MO, United States
- Department of Neurology, Washington University in St. Louis School of Medicine, St. Louis, MO, United States
| | - Arindam R. Chatterjee
- Mallinckrodt Institute of Radiology, Washington University in St. Louis School of Medicine, St. Louis, MO, United States
- Department of Neurological Surgery, Washington University in St. Louis School of Medicine, St. Louis, MO, United States
- Department of Neurology, Washington University in St. Louis School of Medicine, St. Louis, MO, United States
| | - Ananth K. Vellimana
- Mallinckrodt Institute of Radiology, Washington University in St. Louis School of Medicine, St. Louis, MO, United States
- Department of Neurological Surgery, Washington University in St. Louis School of Medicine, St. Louis, MO, United States
- Department of Neurology, Washington University in St. Louis School of Medicine, St. Louis, MO, United States
| | - Akash P. Kansagra
- Department of Neurointerventional Surgery, California Center of Neurointerventional Surgery, San Diego, CA, United States
| | - Colin P. Derdeyn
- Department of Radiology, University of Iowa School of Medicine, Iowa City, IA, United States
| | - Dewitte T. Cross
- Mallinckrodt Institute of Radiology, Washington University in St. Louis School of Medicine, St. Louis, MO, United States
- Department of Neurological Surgery, Washington University in St. Louis School of Medicine, St. Louis, MO, United States
| | - Christopher J. Moran
- Mallinckrodt Institute of Radiology, Washington University in St. Louis School of Medicine, St. Louis, MO, United States
- Department of Neurological Surgery, Washington University in St. Louis School of Medicine, St. Louis, MO, United States
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12
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Lauzier DC, Cler SJ, Vellimana AK, Osbun JW, Chatterjee AR, Derdeyn CP, Cross DT, Moran CJ, Kansagra AP. Evolution of Elective Intracranial Aneurysm Treatment. World Neurosurg 2022; 168:309-310. [PMID: 36055621 DOI: 10.1016/j.wneu.2022.08.133] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- David C Lauzier
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, Missouri, USA.
| | - Samuel J Cler
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Ananth K Vellimana
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, Missouri, USA; Department of Neurological Surgery, Washington University School of Medicine, St. Louis, Missouri, USA; Department of Neurology, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Joshua W Osbun
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, Missouri, USA; Department of Neurological Surgery, Washington University School of Medicine, St. Louis, Missouri, USA; Department of Neurology, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Arindam R Chatterjee
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, Missouri, USA; Department of Neurological Surgery, Washington University School of Medicine, St. Louis, Missouri, USA; Department of Neurology, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Colin P Derdeyn
- Department of Radiology, University of Iowa School of Medicine, Iowa City, USA
| | - Dewitte T Cross
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, Missouri, USA; Department of Neurological Surgery, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Christopher J Moran
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, Missouri, USA; Department of Neurological Surgery, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Akash P Kansagra
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, Missouri, USA; Department of Neurological Surgery, Washington University School of Medicine, St. Louis, Missouri, USA; Department of Neurology, Washington University School of Medicine, St. Louis, Missouri, USA
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13
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Clarke JV, Brier LM, Rahn RM, Diwan D, Yuan JY, Bice AR, Imai SI, Vellimana AK, Culver JP, Zipfel GJ. SIRT1 mediates hypoxic postconditioning- and resveratrol-induced protection against functional connectivity deficits after subarachnoid hemorrhage. J Cereb Blood Flow Metab 2022; 42:1210-1223. [PMID: 35137611 PMCID: PMC9207494 DOI: 10.1177/0271678x221079902] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Functional connectivity (FC) is a sensitive metric that provides a readout of whole cortex coordinate neural activity in a mouse model. We examine the impact of experimental SAH modeled through endovascular perforation, and the effectiveness of subsequent treatment on FC, through three key questions: 1) Does the endovascular perforation model of SAH induce deficits in FC; 2) Does exposure to hypoxic conditioning provide protection against these FC deficits and, if so, is this neurovascular protection SIRT1-mediated; and 3) does treatment with the SIRT1 activator resveratrol alone provide protection against these FC deficits? Cranial windows were adhered on skull-intact mice that were then subjected to either sham or SAH surgery and either left untreated or treated with hypoxic post-conditioning (with or without EX527) or resveratrol for 3 days. Mice were imaged 3 days post-SAH/sham surgery, temporally aligned with the onset of major SAH sequela in mice. Here we show that the endovascular perforation model of SAH induces global and network-specific deficits in FC by day 3, corresponding with the time frame of DCI in mice. Hypoxic conditioning provides SIRT1-mediated protection against these network-specific FC deficits post-SAH, as does treatment with resveratrol. Conditioning-based strategies provide multifaceted neurovascular protection in experimental SAH.
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Affiliation(s)
- Julian V Clarke
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, USA
| | - Lindsey M Brier
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, USA
| | - Rachel M Rahn
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, USA
| | - Deepti Diwan
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, USA
| | - Jane Y Yuan
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, USA
| | - Annie R Bice
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, USA
| | - Shin-Ichiro Imai
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, USA
| | - Ananth K Vellimana
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, USA
| | - Joseph P Culver
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, USA
| | - Gregory J Zipfel
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, USA
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14
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Diwan D, Vellimana AK, Aum DJ, Clarke J, Nelson JW, Lawrence M, Han BH, Gidday JM, Zipfel GJ. Sirtuin 1 Mediates Protection Against Delayed Cerebral Ischemia in Subarachnoid Hemorrhage in Response to Hypoxic Postconditioning. J Am Heart Assoc 2021; 10:e021113. [PMID: 34622677 PMCID: PMC8751859 DOI: 10.1161/jaha.121.021113] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Background Many therapies designed to prevent delayed cerebral ischemia (DCI) and improve neurological outcome in aneurysmal subarachnoid hemorrhage (SAH) have failed, likely because of targeting only one element of what has proven to be a multifactorial disease. We previously demonstrated that initiating hypoxic conditioning before SAH (hypoxic preconditioning) provides powerful protection against DCI. Here, we expanded upon these findings to determine whether hypoxic conditioning delivered at clinically relevant time points after SAH (hypoxic postconditioning) provides similarly robust DCI protection. Methods and Results In this study, we found that hypoxic postconditioning (8% O2 for 2 hours) initiated 3 hours after SAH provides strong protection against cerebral vasospasm, microvessel thrombi, and neurological deficits. By pharmacologic and genetic inhibition of SIRT1 (sirtuin 1) using EX527 and global Sirt1-/- mice, respectively, we demonstrated that this multifaceted DCI protection is SIRT1 mediated. Moreover, genetic overexpression of SIRT1 using Sirt1-Tg mice, mimicked the DCI protection afforded by hypoxic postconditioning. Finally, we found that post-SAH administration of resveratrol attenuated cerebral vasospasm, microvessel thrombi, and neurological deficits, and did so in a SIRT1-dependent fashion. Conclusions The present study indicates that hypoxic postconditioning provides powerful DCI protection when initiated at clinically relevant time points, and that pharmacologic augmentation of SIRT1 activity after SAH can mimic this beneficial effect. We conclude that conditioning-based therapies administered after SAH hold translational promise for patients with SAH and warrant further investigation.
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Affiliation(s)
- Deepti Diwan
- Department of Neurological Surgery Washington University School of Medicine St. Louis MO
| | - Ananth K Vellimana
- Department of Neurological Surgery Washington University School of Medicine St. Louis MO
| | - Diane J Aum
- Department of Neurological Surgery Washington University School of Medicine St. Louis MO
| | - Julian Clarke
- Department of Neurological Surgery Washington University School of Medicine St. Louis MO
| | - James W Nelson
- Department of Neurological Surgery Washington University School of Medicine St. Louis MO
| | - Molly Lawrence
- Department of Neurological Surgery Washington University School of Medicine St. Louis MO
| | - Byung Hee Han
- Department of Pharmacology A.T. Still University of Health SciencesKirksville College of Osteopathic Medicine Kirksville MO
| | - Jeffrey M Gidday
- Departments of Ophthalmology, Physiology, Biochemistry, and Neuroscience Louisiana State University New Orleans LA
| | - Gregory J Zipfel
- Department of Neurological Surgery Washington University School of Medicine St. Louis MO.,Department of Neurology Washington University School of Medicine St. Louis MO
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15
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Lauzier DC, Vellimana AK, Chatterjee AR, Osbun JW, Moran CJ, Zipfel GJ, Kansagra AP. Return of the lesion: a meta-analysis of 1134 angiographically cured pediatric arteriovenous malformations. J Neurosurg Pediatr 2021:1-8. [PMID: 34507285 DOI: 10.3171/2021.6.peds21227] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Accepted: 06/16/2021] [Indexed: 11/06/2022]
Abstract
OBJECTIVE Brain arteriovenous malformations (AVMs) carry a risk of rupture and subsequent morbidity or mortality unless fully treated. AVMs in pediatric patients are known to occasionally recur after obliteration. The objective of this study was to characterize the risk of AVM recurrence following angiographically confirmed obliteration in children. METHODS Consecutive pediatric AVMs treated at a single center were identified from a prospective database. Patients with angiographically confirmed AVM obliteration following treatment were included in this study. Associations between AVM recurrence and patient or procedural factors were characterized using the two-tailed Fisher exact test or Mann-Whitney U-test. A literature search was conducted using PubMed, Scopus, Embase, and the Clarivate Web of Science with defined search criteria, and eligible studies were included alongside this study cohort in a meta-analysis. Rates of AVM recurrence following obliteration were pooled across studies with a random-effects model and reported with 95% confidence intervals (CIs). RESULTS Recurrence after angiographic confirmation of AVM obliteration was observed in 10.4% (7/67) of pediatric AVMs treated at the authors' center. Patients with recurrent AVMs were significantly younger than those without recurrence (p = 0.002). In the meta-analysis, which included 1134 patients across 24 studies, the rate of recurrence was 4.8% (95% CI 3.0%-6.7%). The rate of AVM recurrence following radiosurgery was 0.7% (95% CI 0%-1.6%), which was significantly lower than the 8.5% rate (95% CI 5.0%-12.0%) following microsurgery. CONCLUSIONS Recurrence of obliterated brain AVMs is common in children. Recurrence is more common in young children and following microsurgery.
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Affiliation(s)
| | | | - Arindam R Chatterjee
- 1Mallinckrodt Institute of Radiology.,2Department of Neurological Surgery, and.,3Department of Neurology, Washington University School of Medicine, St. Louis, Missouri
| | - Joshua W Osbun
- 1Mallinckrodt Institute of Radiology.,2Department of Neurological Surgery, and.,3Department of Neurology, Washington University School of Medicine, St. Louis, Missouri
| | - Christopher J Moran
- 1Mallinckrodt Institute of Radiology.,2Department of Neurological Surgery, and
| | - Gregory J Zipfel
- 2Department of Neurological Surgery, and.,3Department of Neurology, Washington University School of Medicine, St. Louis, Missouri
| | - Akash P Kansagra
- 1Mallinckrodt Institute of Radiology.,2Department of Neurological Surgery, and.,3Department of Neurology, Washington University School of Medicine, St. Louis, Missouri
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16
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Abecassis IJ, Zeeshan Q, Feroze AH, Ene C, Vellimana AK, Sekhar LN. Subtemporal, Transapical, and Transcavernous Approach to Clip Low-Lying Basilar Tip Aneurysm: 2-Dimensional Operative Video. Oper Neurosurg (Hagerstown) 2021; 20:E436. [PMID: 33548927 DOI: 10.1093/ons/opab005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Accepted: 11/20/2020] [Indexed: 11/12/2022] Open
Abstract
Basilar tip aneurysm clipping is technically challenging because of the depth of operative corridor, rarity in presentation, and important perforators supplying deep, critical structures. Two major approaches to basilar tip aneurysms include (1) a frontotemporal (transorbital) trans-sylvian approach for most aneurysms and (2) a modified subtemporal approach for aneurysms with low-lying necks. A 53-yr-old woman presented to our institution with a large unruptured basilar tip aneurysm notable for a low, broad neck (6.4 mm). After discussion of risks and benefits of endovascular vs surgical options, the patient consented to operative intervention. She underwent a right frontotemporal craniotomy with zygomatic osteotomy, intradural petrous apicectomy, elective sectioning of the fourth cranial nerve (CN IV), and intracavernous removal of the dorsum sellae and posterior clinoid process to provide more space for aneurysm dissection. After temporary clipping of the basilar artery, the perforating arteries were dissected free from the aneurysm and the aneurysm occluded with 2 fenestrated clips. Important technical nuances of the approach include (1) achieving ample working room for temporary occlusion aneurysm dissection, (2) careful dissection of the perforators and contralateral P1, and (3) utilization of 2 fenestrated clips to accommodate and preserve the ipsilateral P1 segment. Postoperative angiogram showed complete aneur-ysmal occlusion. Postoperatively, the patient demonstrated mild cognitive impairment and a right CN IV palsy. At 6-wk follow-up, cognition recovered to normalcy. More recently, at 12-mo follow-up, the patient noted intermittent diplopia. Formal neuro-ophthalmologic assessment confirmed persistence of a CN IV palsy treated with prism lenses but no other neurological deficits.
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Affiliation(s)
| | - Qazi Zeeshan
- Department of Neurosurgery, University of Washington, Seattle, Washington, USA
| | - Abdullah H Feroze
- Department of Neurosurgery, University of Washington, Seattle, Washington, USA
| | - Chibawanye Ene
- Department of Neurosurgery, University of Washington, Seattle, Washington, USA
| | - Ananth K Vellimana
- Department of Neurosurgery, University of Washington, Seattle, Washington, USA
| | - Laligam N Sekhar
- Department of Neurosurgery, University of Washington, Seattle, Washington, USA
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17
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Abstract
Cervical carotid and vertebral artery traumatic injuries can have a devastating natural history. This article reviews the epidemiology, mechanisms of injury, clinical presentation, and classification systems pertinent to consideration of endovascular treatment. The growing role of modern endovascular techniques for the treatment of these diseases is presented to equip endovascular surgeons with a framework for critically assessing patients presenting with traumatic cervical cerebrovascular injury.
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Affiliation(s)
- Ananth K Vellimana
- Department of Neurological Surgery, Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, Missouri
| | - Jayson Lavie
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, Missouri
| | - Arindam Rano Chatterjee
- Department of Neurological Surgery, Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, Missouri
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18
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Shah AS, Sylvester PT, Yahanda AT, Vellimana AK, Dunn GP, Evans J, Rich KM, Dowling JL, Leuthardt EC, Dacey RG, Kim AH, Grubb RL, Zipfel GJ, Oswood M, Jensen RL, Sutherland GR, Cahill DP, Abram SR, Honeycutt J, Shah M, Tao Y, Chicoine MR. Intraoperative MRI for newly diagnosed supratentorial glioblastoma: a multicenter-registry comparative study to conventional surgery. J Neurosurg 2020:1-10. [PMID: 33035996 DOI: 10.3171/2020.6.jns19287] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Accepted: 06/04/2020] [Indexed: 11/06/2022]
Abstract
OBJECTIVE Intraoperative MRI (iMRI) is used in the surgical treatment of glioblastoma, with uncertain effects on outcomes. The authors evaluated the impact of iMRI on extent of resection (EOR) and overall survival (OS) while controlling for other known and suspected predictors. METHODS A multicenter retrospective cohort of 640 adult patients with newly diagnosed supratentorial glioblastoma who underwent resection was evaluated. iMRI was performed in 332/640 cases (51.9%). Reviews of MRI features and tumor volumetric analysis were performed on a subsample of cases (n = 286; 110 non-iMRI, 176 iMRI) from a single institution. RESULTS The median age was 60.0 years (mean 58.5 years, range 20.5-86.3 years). The median OS was 17.0 months (95% CI 15.6-18.4 months). Gross-total resection (GTR) was achieved in 403/640 cases (63.0%). Kaplan-Meier analysis of 286 cases with volumetric analysis for EOR (grouped into 100%, 95%-99%, 80%-94%, and 50%-79%) showed longer OS for 100% EOR compared to all other groups (p < 0.01). Additional resection after iMRI was performed in 104/122 cases (85.2%) with initial subtotal resection (STR), leading to a 6.3% mean increase in EOR and a 2.2-cm3 mean decrease in tumor volume. For iMRI cases with volumetric analysis, the GTR rate increased from 54/176 (30.7%) on iMRI to 126/176 (71.5%) postoperatively. The EOR was significantly higher in the iMRI group for intended GTR and STR groups (p = 0.02 and p < 0.01, respectively). Predictors of GTR on multivariate logistic regression included iMRI use and intended GTR. Predictors of shorter OS on multivariate Cox regression included older age, STR, isocitrate dehydrogenase 1 (IDH1) wild type, no O6-methylguanine DNA methyltransferase (MGMT) methylation, and no Stupp therapy. iMRI was a significant predictor of OS on univariate (HR 0.82, 95% CI 0.69-0.98; p = 0.03) but not multivariate analyses. Use of iMRI was not associated with an increased rate of new permanent neurological deficits. CONCLUSIONS GTR increased OS for patients with newly diagnosed glioblastoma after adjusting for other prognostic factors. iMRI increased EOR and GTR rate and was a significant predictor of GTR on multivariate analysis; however, iMRI was not an independent predictor of OS. Additional supporting evidence is needed to determine the clinical benefit of iMRI in the management of glioblastoma.
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Affiliation(s)
- Amar S Shah
- 1Department of Neurosurgery, Washington University School of Medicine, St. Louis, Missouri
| | - Peter T Sylvester
- 1Department of Neurosurgery, Washington University School of Medicine, St. Louis, Missouri
| | - Alexander T Yahanda
- 1Department of Neurosurgery, Washington University School of Medicine, St. Louis, Missouri
| | - Ananth K Vellimana
- 1Department of Neurosurgery, Washington University School of Medicine, St. Louis, Missouri
| | - Gavin P Dunn
- 1Department of Neurosurgery, Washington University School of Medicine, St. Louis, Missouri
| | - John Evans
- 1Department of Neurosurgery, Washington University School of Medicine, St. Louis, Missouri
| | - Keith M Rich
- 1Department of Neurosurgery, Washington University School of Medicine, St. Louis, Missouri
| | - Joshua L Dowling
- 1Department of Neurosurgery, Washington University School of Medicine, St. Louis, Missouri
| | - Eric C Leuthardt
- 1Department of Neurosurgery, Washington University School of Medicine, St. Louis, Missouri
| | - Ralph G Dacey
- 1Department of Neurosurgery, Washington University School of Medicine, St. Louis, Missouri
| | - Albert H Kim
- 1Department of Neurosurgery, Washington University School of Medicine, St. Louis, Missouri
| | - Robert L Grubb
- 1Department of Neurosurgery, Washington University School of Medicine, St. Louis, Missouri
| | - Gregory J Zipfel
- 1Department of Neurosurgery, Washington University School of Medicine, St. Louis, Missouri
| | - Mark Oswood
- 2Department of Radiology, University of Minnesota, Minneapolis, Minnesota
- 3Allina Health, Minneapolis, Minnesota
| | - Randy L Jensen
- 4Department of Neurosurgery, Huntsman Cancer Institute, University of Utah, Salt Lake City, Utah
| | - Garnette R Sutherland
- 5Department of Clinical Sciences and Hotchkiss Brain Institute, University of Calgary, Alberta, Canada
| | - Daniel P Cahill
- 6Department of Neurosurgery, Massachusetts General Hospital, Boston, Massachusetts
| | - Steven R Abram
- 7Department of Neurosurgery, St. Thomas Hospital, Nashville, Tennessee
| | - John Honeycutt
- 8Department of Neurosurgery, Cook Children's Hospital, Fort Worth, Texas; and
| | - Mitesh Shah
- 9Department of Neurological Surgery, Goodman Campbell and Indiana University, Indianapolis, Indiana
| | - Yu Tao
- 1Department of Neurosurgery, Washington University School of Medicine, St. Louis, Missouri
| | - Michael R Chicoine
- 1Department of Neurosurgery, Washington University School of Medicine, St. Louis, Missouri
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Vellimana AK, Aum DJ, Diwan D, Clarke JV, Nelson JW, Lawrence M, Han BH, Gidday JM, Zipfel GJ. SIRT1 mediates hypoxic preconditioning induced attenuation of neurovascular dysfunction following subarachnoid hemorrhage. Exp Neurol 2020; 334:113484. [PMID: 33010255 DOI: 10.1016/j.expneurol.2020.113484] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Revised: 09/18/2020] [Accepted: 09/24/2020] [Indexed: 01/01/2023]
Abstract
BACKGROUND AND PURPOSE Vasospasm and delayed cerebral ischemia (DCI) contribute significantly to the morbidity/mortality associated with aneurysmal subarachnoid hemorrhage (SAH). While considerable research effort has focused on preventing or reversing vasospasm, SAH-induced brain injury occurs in response to a multitude of concomitantly acting pathophysiologic mechanisms. In this regard, the pleiotropic epigenetic responses to conditioning-based therapeutics may provide an ideal SAH therapeutic strategy. We previously documented the ability of hypoxic preconditioning (PC) to attenuate vasospasm and neurological deficits after SAH, in a manner that depends on the activity of endothelial nitric oxide synthase. The present study was undertaken to elucidate whether the NAD-dependent protein deacetylase sirtuin isoform SIRT1 is an upstream mediator of hypoxic PC-induced protection, and to assess the efficacy of the SIRT1-activating polyphenol Resveratrol as a pharmacologic preconditioning therapy. METHODS Wild-type C57BL/6J mice were utilized in the study and subjected to normoxia or hypoxic PC. Surgical procedures included induction of SAH via endovascular perforation or sham surgery. Multiple endpoints were assessed including cerebral vasospasm, neurobehavioral deficits, SIRT1 expression via quantitative real-time PCR for mRNA, and western blot for protein quantification. Pharmacological agents utilized in the study include EX-527 (SIRT1 inhibitor), and Resveratrol (SIRT1 activator). RESULTS Hypoxic PC leads to rapid and sustained increase in cerebral SIRT1 mRNA and protein expression. SIRT1 inhibition blocks the protective effects of hypoxic PC on vasospasm and neurological deficits. Resveratrol pretreatment dose-dependently abrogates vasospasm and attenuates neurological deficits following SAH - beneficial effects that were similarly blocked by pharmacologic inhibition of SIRT1. CONCLUSION SIRT1 mediates hypoxic preconditioning-induced protection against neurovascular dysfunction after SAH. Resveratrol mimics this neurovascular protection, at least in part, via SIRT1. Activation of SIRT1 is a promising, novel, pleiotropic therapeutic strategy to combat DCI after SAH.
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Affiliation(s)
- Ananth K Vellimana
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Diane J Aum
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Deepti Diwan
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Julian V Clarke
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - James W Nelson
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Molly Lawrence
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Byung Hee Han
- Department of Pharmacology, A.T. Still University of Health Sciences, Kirksville College of Osteopathic Medicine, Kirksville, MO 63501, USA
| | - Jeffrey M Gidday
- Departments of Ophthalmology, Physiology, Biochemistry, and Neuroscience, Louisiana State University, New Orleans, Louisiana, USA
| | - Gregory J Zipfel
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, MO 63110, USA; Department of Neurology, Washington University School of Medicine, St. Louis, MO, USA.
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20
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Clarke JV, Suggs JM, Diwan D, Lee JV, Lipsey K, Vellimana AK, Zipfel GJ. Microvascular platelet aggregation and thrombosis after subarachnoid hemorrhage: A review and synthesis. J Cereb Blood Flow Metab 2020; 40:1565-1575. [PMID: 32345104 PMCID: PMC7370365 DOI: 10.1177/0271678x20921974] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Delayed cerebral ischemia (DCI) after aneurysmal subarachnoid hemorrhage (SAH) has been associated with numerous pathophysiological sequelae, including large artery vasospasm and microvascular thrombosis. The focus of this review is to provide an overview of experimental animal model studies and human autopsy studies that explore the temporal-spatial characterization and mechanism of microvascular platelet aggregation and thrombosis following SAH, as well as to critically assess experimental studies and clinical trials highlighting preventative therapeutic options against this highly morbid pathophysiological process. Upon review of the literature, we discovered that microvascular platelet aggregation and thrombosis occur after experimental SAH across multiple species and SAH induction techniques in a similar time frame to other components of DCI, occurring in the cerebral cortex and hippocampus across both hemispheres. We discuss the relationship of these findings to human autopsy studies. In the final section of this review, we highlight the important therapeutic options for targeting microvascular platelet aggregation and thrombosis, and emphasize why therapeutic targeting of this neurovascular pathology may improve patient care. We encourage ongoing research into the pathophysiology of SAH and DCI, especially in regard to microvascular platelet aggregation and thrombosis and the translation to randomized clinical trials.
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Affiliation(s)
- Julian V Clarke
- Washington University School of Medicine, Saint Louis, MO, USA
| | - Julia M Suggs
- Washington University School of Medicine, Saint Louis, MO, USA
| | - Deepti Diwan
- Washington University School of Medicine, Saint Louis, MO, USA
| | - Jin V Lee
- Washington University School of Medicine, Saint Louis, MO, USA
| | - Kim Lipsey
- Washington University School of Medicine, Saint Louis, MO, USA
| | - Ananth K Vellimana
- Neurological Surgery, Washington University School of Medicine, , Saint Louis, MO, USA
| | - Gregory J Zipfel
- Neurological Surgery, Washington University School of Medicine, , Saint Louis, MO, USA
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21
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Vellimana AK, Washington CW, Yarbrough CK, Pilgram TK, Hoh BL, Derdeyn CP, Zipfel GJ. Thrombolysis is an Independent Risk Factor for Poor Outcome After Carotid Revascularization. Neurosurgery 2019; 83:922-930. [PMID: 29136204 DOI: 10.1093/neuros/nyx551] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2015] [Accepted: 10/02/2017] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Thrombolysis is the standard of care for acute ischemic stroke patients presenting in the appropriate time window. Studies suggest that the risk of recurrent ischemia is lower if carotid revascularization is performed early after the index event. The safety of early carotid revascularization in this patient population is unclear. OBJECTIVE To evaluate the safety of carotid revascularization in patients who received thrombolysis for acute ischemic stroke. METHODS The Nationwide Inpatient Sample database was queried for patients admitted through the emergency room with a primary diagnosis of carotid stenosis and/or occlusion. Each patient was reviewed for administration of thrombolysis, carotid endarterectomy, (CEA) or carotid angioplasty and stenting (CAS). Primary endpoints were intracerebral hemorrhage (ICH), postprocedural stroke (PPS), poor outcome, and in-hospital mortality. Potential risk factors were examined using univariate and multivariate analyses. RESULTS A total of 310 257 patients were analyzed. Patients who received tissue plasminogen activator (tPA) and underwent either CEA or CAS had a significantly higher risk of developing an ICH or PPS than patients who underwent either CEA or CAS without tPA administration. The increased risk of ICH or PPS in tPA-treated patients who underwent carotid revascularization diminished with time, and became similar to patients who underwent carotid revascularization without tPA administration by 7 d after thrombolysis. Patients who received tPA and underwent CEA or CAS also had higher odds of poor outcome and in-hospital mortality. CONCLUSION Thrombolysis is a strong risk factor for ICH, PPS, poor outcome, and in-hospital mortality in patients with carotid stenosis/occlusion who undergo carotid revascularization. The increased risk of ICH or PPS due to tPA declines with time after thrombolysis. Delaying carotid revascularization in these patients may therefore be appropriate. This delay, however, will expose these patients to the risk of recurrent stroke. Future studies are needed to determine the relative risks of these 2 adverse events.
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Affiliation(s)
- Ananth K Vellimana
- Department of Neurological Surgery, Washington University School of Medi-cine, St. Louis, Missouri
| | - Chad W Washington
- Department of Neurological Surgery, Washington University School of Medi-cine, St. Louis, Missouri
| | - Chester K Yarbrough
- Department of Neurological Surgery, Washington University School of Medi-cine, St. Louis, Missouri
| | - Thomas K Pilgram
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, Missouri
| | - Brian L Hoh
- Department of Neurosurgery, University of Florida, Gainesville, Florida
| | - Colin P Derdeyn
- Department of Neurological Surgery, Washington University School of Medi-cine, St. Louis, Missouri.,Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, Missouri
| | - Gregory J Zipfel
- Department of Neurological Surgery, Washington University School of Medi-cine, St. Louis, Missouri
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22
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Athiraman U, Aum D, Vellimana AK, Osbun JW, Dhar R, Tempelhoff R, Zipfel GJ. Evidence for a conditioning effect of inhalational anesthetics on angiographic vasospasm after aneurysmal subarachnoid hemorrhage. J Neurosurg 2019; 133:1-7. [PMID: 31200380 DOI: 10.3171/2019.3.jns183512] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2018] [Accepted: 03/24/2019] [Indexed: 01/30/2023]
Abstract
OBJECTIVE Delayed cerebral ischemia (DCI) after aneurysmal subarachnoid hemorrhage (SAH) is characterized by large-artery vasospasm, distal autoregulatory dysfunction, cortical spreading depression, and microvessel thrombi. Large-artery vasospasm has been identified as an independent predictor of poor outcome in numerous studies. Recently, several animal studies have identified a strong protective role for inhalational anesthetics against secondary brain injury after SAH including DCI-a phenomenon referred to as anesthetic conditioning. The aim of the present study was to assess the potential role of inhalational anesthetics against cerebral vasospasm and DCI in patients suffering from an SAH. METHODS After IRB approval, data were collected retrospectively for all SAH patients admitted to the authors' hospital between January 1, 2010, and December 31, 2013, who received general anesthesia with either inhalational anesthetics only (sevoflurane or desflurane) or combined inhalational (sevoflurane or desflurane) and intravenous (propofol) anesthetics during aneurysm treatment. The primary outcomes were development of angiographic vasospasm and development of DCI during hospitalization. Univariate and logistic regression analyses were performed to identify independent predictors of these endpoints. RESULTS The cohort included 157 SAH patients whose mean age was 56 ± 14 (± SD). An inhalational anesthetic-only technique was employed in 119 patients (76%), while a combination of inhalational and intravenous anesthetics was employed in 34 patients (22%). As expected, patients in the inhalational anesthetic-only group were exposed to significantly more inhalational agent than patients in the combination anesthetic group (p < 0.05). Multivariate logistic regression analysis identified inhalational anesthetic-only technique (OR 0.35, 95% CI 0.14-0.89), Hunt and Hess grade (OR 1.51, 95% CI 1.03-2.22), and diabetes (OR 0.19, 95% CI 0.06-0.55) as significant predictors of angiographic vasospasm. In contradistinction, the inhalational anesthetic-only technique had no significant impact on the incidence of DCI or functional outcome at discharge, though greater exposure to desflurane (as measured by end-tidal concentration) was associated with a lower incidence of DCI. CONCLUSIONS These data represent the first evidence in humans that inhalational anesthetics may exert a conditioning protective effect against angiographic vasospasm in SAH patients. Future studies will be needed to determine whether optimized inhalational anesthetic paradigms produce definitive protection against angiographic vasospasm; whether they protect against other events leading to secondary brain injury after SAH, including microvascular thrombi, autoregulatory dysfunction, blood-brain barrier breakdown, neuroinflammation, and neuronal cell death; and, if so, whether this protection ultimately improves patient outcome.
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Affiliation(s)
| | | | | | | | - Rajat Dhar
- 3Neurology, Washington University, St. Louis, Missouri
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23
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Arias EJ, Bruck B, Vellimana AK, Eby C, Reynolds MR, Blinder MA, Zipfel GJ. Plasmapheresis for Management of Antiphospholipid Syndrome in the Neurosurgical Patient. Oper Neurosurg (Hagerstown) 2019; 16:E124-E129. [PMID: 29800263 DOI: 10.1093/ons/opy135] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2018] [Accepted: 04/26/2018] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND AND IMPORTANCE Antiphospholipid syndrome (APS) is an autoimmune disorder associated with a hypercoagulable state and increased risk of intraoperative and postoperative thrombosis. Few neurosurgical studies have examined the management of these patients, though the standard of care in most other disciplines involves the use of anticoagulation therapy. However, this is associated with risks such as hemorrhage, thrombosis due to warfarin withdrawal, and is not compatible with operative intervention. CLINICAL PRESENTATION We report the cases of 2 antiphospholipid positive patients who were on anticoagulant therapy and underwent surgical bypasses and received perioperative management with plasmapheresis. The first was a 44-yr-old woman who presented with worsening vision, recurring headaches, and a known left internal carotid artery aneurysm that was unsuccessfully treated twice via extracranial to intracranial (ECIC) bypass at another institution. Preoperative tests at our institution revealed elevated beta 2 glycoprotein 1 IgA autoantibodies. The second case was a 24-yr-old woman with previously diagnosed APS, who presented for surgical evaluation of moyamoya disease after sustaining recurrent left hemispheric strokes. Both cases were managed with perioperative plasmapheresis to avoid the need for anticoagulation during the perioperative period, and both underwent successful ECIC bypass procedures without perioperative ischemic or hemorrhagic complications. CONCLUSION Management of neurosurgical patients with APS can be a precarious proposition. We describe the successful use of plasmapheresis and antiplatelet therapy to better manage patients undergoing neurosurgical procedures, specifically ECIC bypass, and feel this approach can be considered in future cases.
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Affiliation(s)
- Eric J Arias
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, Missouri
| | - Brent Bruck
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, Missouri
| | - Ananth K Vellimana
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, Missouri
| | - Charles Eby
- Department of Pathology & Immunology, Washington University School of Medicine, St. Louis, Missouri
| | - Matthew R Reynolds
- Department of Neurological Surgery, Emory University School of Medicine, Atlanta, Georgia
| | - Morey A Blinder
- Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri
| | - Gregory J Zipfel
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, Missouri.,Department of Neurology, Washington University School of Medicine, St. Louis, Missouri
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24
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Mahlokozera T, Vellimana AK, Li T, Mao DD, Zohny ZS, Kim DH, Tran DD, Marcus DS, Fouke SJ, Campian JL, Dunn GP, Miller CA, Kim AH. Biological and therapeutic implications of multisector sequencing in newly diagnosed glioblastoma. Neuro Oncol 2019; 20:472-483. [PMID: 29244145 DOI: 10.1093/neuonc/nox232] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Background Diagnostic workflows for glioblastoma (GBM) patients increasingly include DNA sequencing-based analysis of a single tumor site following biopsy or resection. We hypothesized that sequencing of multiple sectors within a given tumor would provide a more comprehensive representation of the molecular landscape and potentially inform therapeutic strategies. Methods Ten newly diagnosed, isocitrate dehydrogenase 1 (IDH1) wildtype GBM tumor samples were obtained from 2 (n = 9) or 4 (n = 1) spatially distinct tumor regions. Tumor and matched blood DNA samples underwent whole-exome sequencing. Results Across all 10 tumors, 51% of mutations were clonal and 3% were subclonal and shared in different sectors, whereas 46% of mutations were subclonal and private. Two of the 10 tumors exhibited a regional hypermutator state despite being treatment naïve, and remarkably, the high mutational load was predominantly limited to one sector in each tumor. Among the canonical cancer-associated genes, only telomerase reverse transcriptase (TERT) promoter mutations were observed in the founding clone in all tumors. Reconstruction of the clonal architecture in different sectors revealed regionally divergent evolution, and integration of data from 2 sectors increased the resolution of inferred clonal architecture in a given tumor. Predicted therapeutic mutations differed in presence and frequency between tumor regions. Similarly, different sectors exhibited significant divergence in the predicted neoantigen landscape. Conclusions The substantial spatial heterogeneity observed in different GBM tumor sectors, especially in spatially restricted hypermutator cases, raises important caveats to our current dependence on single-sector molecular information to guide either targeted or immune-based treatments.
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Affiliation(s)
- Tatenda Mahlokozera
- Department of Neurological Surgery, Washington University School of Medicine, St Louis, Missouri
| | - Ananth K Vellimana
- Department of Neurological Surgery, Washington University School of Medicine, St Louis, Missouri
| | - Tiandao Li
- McDonnell Genome Institute, Washington University School of Medicine, St Louis, Missouri
| | - Diane D Mao
- Department of Neurological Surgery, Washington University School of Medicine, St Louis, Missouri
| | - Zohny S Zohny
- Department of Neurological Surgery, Washington University School of Medicine, St Louis, Missouri
| | - David H Kim
- Department of Neurological Surgery, Washington University School of Medicine, St Louis, Missouri
| | - David D Tran
- Lillian S. Wells Department of Neurosurgery, University of Florida College of Medicine, Gainesville, Florida
| | - Daniel S Marcus
- Department of Radiology, Washington University School of Medicine, St Louis, Missouri
| | - Sarah J Fouke
- Department of Neurosurgery, St Luke's Hospital, St Louis, Missouri
| | - Jian L Campian
- Siteman Cancer Center, Washington University School of Medicine, St Louis, Missouri
| | - Gavin P Dunn
- Department of Neurological Surgery, Washington University School of Medicine, St Louis, Missouri.,Siteman Cancer Center, Washington University School of Medicine, St Louis, Missouri.,Center for Human Immunology and Immunotherapy Programs, Washington University School of Medicine, St Louis, Missouri.,Department of Pathology and Immunology, Washington University School of Medicine, St Louis, Missouri
| | - Christopher A Miller
- McDonnell Genome Institute, Washington University School of Medicine, St Louis, Missouri
| | - Albert H Kim
- Department of Neurological Surgery, Washington University School of Medicine, St Louis, Missouri.,Siteman Cancer Center, Washington University School of Medicine, St Louis, Missouri.,Department of Neurology, Washington University School of Medicine, St Louis, Missouri.,Department of Developmental Biology, Washington University School of Medicine, St Louis, Missouri
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25
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Shah AS, Sylvester P, Vellimana AK, Dunn GP, Evans J, Jensen RL, Honeycutt JH, Sutherland GR, Cahill DP, Shah MV, Abram SR, Oswood MC, Kim AH, Leuthardt EC, Dowling JL, Rich KM, Dacey RG, Zipfel GJ, Tao Y, Chicoine MR. 215 The Impact of Intraoperative MRI and Other Factors on Survival for Patients With Newly Diagnosed Glioblastoma. A Multicenter Assessment of Over 800 Patients. Neurosurgery 2018. [DOI: 10.1093/neuros/nyy303.215] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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26
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Vellimana AK, Diwan D, Clarke J, Gidday JM, Zipfel GJ. SIRT1 Activation: A Potential Strategy for Harnessing Endogenous Protection Against Delayed Cerebral Ischemia After Subarachnoid Hemorrhage. Neurosurgery 2018; 65:1-5. [PMID: 31076789 DOI: 10.1093/neuros/nyy201] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Accepted: 05/21/2018] [Indexed: 01/18/2023] Open
Affiliation(s)
- Ananth K Vellimana
- Department of Neurological Surgery, Washington University School of Medi-cine, St. Louis, Missouri
| | - Deepti Diwan
- Department of Neurological Surgery, Washington University School of Medi-cine, St. Louis, Missouri
| | - Julian Clarke
- Department of Neurological Surgery, Washington University School of Medi-cine, St. Louis, Missouri
| | - Jeffrey M Gidday
- Department of Ophthalmology, Louisiana State University Health Sciences Center, New Orleans, Louisiana
| | - Gregory J Zipfel
- Department of Neurological Surgery, Washington University School of Medi-cine, St. Louis, Missouri
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27
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Raman HS, Santanam L, Vellimana AK, Drzymala RE, Tsien CI, Zipfel GJ. Completion of Gamma Knife radiosurgery for AVM treatment after unplanned interruption-technical note. Acta Neurochir (Wien) 2018; 160:1343-1347. [PMID: 29455411 DOI: 10.1007/s00701-018-3493-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Accepted: 02/10/2018] [Indexed: 12/01/2022]
Abstract
BACKGROUND AND IMPORTANCE Gamma Knife radiosurgery is an established technique for non-urgent treatment of various intracranial pathologies. Intra-procedural dislodgement of the stereotactic frame is an uncommon occurrence that could lead to abortion of ongoing treatment and necessitate more invasive treatment strategies. CLINICAL PRESENTATION In this case report, we describe a novel method for resumption of Gamma Knife treatment after an unplanned intra-procedural interruption. The case example involves a radiosurgical treatment of a Spetzler-Martin grade I arteriovenous malformation. CONCLUSION Our technique involves integration of scans and coordinate systems from two imaging sessions using the composite isodose line to resolve translational differences, thereby limiting delivery of remaining shots to the untreated region of the lesion. MRI follow-up at 13 months showed a reduction in the nidus size with no evidence of any radiation injury to the surrounding brain parenchyma. We believe this technique will allow care teams to effectively salvage interrupted Gamma Knife procedures and reduce progression to more invasive treatment options.
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Affiliation(s)
- Hari S Raman
- Department of Neurological Surgery, Washington University School of Medicine, 660 S. Euclid Ave, Campus Box 8057, St. Louis, MO, 63110, USA
| | - Lakshmi Santanam
- Department of Radiation Oncology, Washington University School of Medicine, St. Louis, MO, USA
| | - Ananth K Vellimana
- Department of Neurological Surgery, Washington University School of Medicine, 660 S. Euclid Ave, Campus Box 8057, St. Louis, MO, 63110, USA
| | - Robert E Drzymala
- Department of Radiation Oncology, Washington University School of Medicine, St. Louis, MO, USA
| | - Christina I Tsien
- Department of Radiation Oncology, Washington University School of Medicine, St. Louis, MO, USA
| | - Gregory J Zipfel
- Department of Neurological Surgery, Washington University School of Medicine, 660 S. Euclid Ave, Campus Box 8057, St. Louis, MO, 63110, USA.
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28
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Roland JL, Griffin N, Hacker CD, Vellimana AK, Akbari SH, Shimony JS, Smyth MD, Leuthardt EC, Limbrick DD. Resting-state functional magnetic resonance imaging for surgical planning in pediatric patients: a preliminary experience. J Neurosurg Pediatr 2017; 20:583-590. [PMID: 28960172 PMCID: PMC5952608 DOI: 10.3171/2017.6.peds1711] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECTIVE Cerebral mapping for surgical planning and operative guidance is a challenging task in neurosurgery. Pediatric patients are often poor candidates for many modern mapping techniques because of inability to cooperate due to their immature age, cognitive deficits, or other factors. Resting-state functional MRI (rs-fMRI) is uniquely suited to benefit pediatric patients because it is inherently noninvasive and does not require task performance or significant cooperation. Recent advances in the field have made mapping cerebral networks possible on an individual basis for use in clinical decision making. The authors present their initial experience translating rs-fMRI into clinical practice for surgical planning in pediatric patients. METHODS The authors retrospectively reviewed cases in which the rs-fMRI analysis technique was used prior to craniotomy in pediatric patients undergoing surgery in their institution. Resting-state analysis was performed using a previously trained machine-learning algorithm for identification of resting-state networks on an individual basis. Network maps were uploaded to the clinical imaging and surgical navigation systems. Patient demographic and clinical characteristics, including need for sedation during imaging and use of task-based fMRI, were also recorded. RESULTS Twenty patients underwent rs-fMRI prior to craniotomy between December 2013 and June 2016. Their ages ranged from 1.9 to 18.4 years, and 12 were male. Five of the 20 patients also underwent task-based fMRI and one underwent awake craniotomy. Six patients required sedation to tolerate MRI acquisition, including resting-state sequences. Exemplar cases are presented including anatomical and resting-state functional imaging. CONCLUSIONS Resting-state fMRI is a rapidly advancing field of study allowing for whole brain analysis by a noninvasive modality. It is applicable to a wide range of patients and effective even under general anesthesia. The nature of resting-state analysis precludes any need for task cooperation. These features make rs-fMRI an ideal technology for cerebral mapping in pediatric neurosurgical patients. This review of the use of rs-fMRI mapping in an initial pediatric case series demonstrates the feasibility of utilizing this technique in pediatric neurosurgical patients. The preliminary experience presented here is a first step in translating this technique to a broader clinical practice.
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Affiliation(s)
- Jarod L. Roland
- Department of Neurological Surgery, Washington University in St. Louis, Missouri
| | - Natalie Griffin
- Department of School of Medicine, Washington University in St. Louis, Missouri
| | - Carl D. Hacker
- Department of Neurological Surgery, Washington University in St. Louis, Missouri
| | - Ananth K. Vellimana
- Department of Neurological Surgery, Washington University in St. Louis, Missouri
| | - S. Hassan Akbari
- Department of Neurological Surgery, Washington University in St. Louis, Missouri
| | - Joshua S. Shimony
- Department of Radiology, Washington University in St. Louis, Missouri
| | - Matthew D. Smyth
- Department of Neurological Surgery, Washington University in St. Louis, Missouri
- Department of Pediatrics, Washington University in St. Louis, Missouri
| | - Eric C. Leuthardt
- Department of Neurological Surgery, Washington University in St. Louis, Missouri
- Department of Neuroscience, Washington University in St. Louis, Missouri
- Department of Biomedical Engineering, Washington University in St. Louis, Missouri
- Department of Mechanical Engineering and Materials Science, Washington University in St. Louis, Missouri
- Center for Innovation in Neuroscience and Technology, Washington University in St. Louis, Missouri
- Brain Laser Center, Washington University in St. Louis, Missouri
| | - David D. Limbrick
- Department of Neurological Surgery, Washington University in St. Louis, Missouri
- Department of Pediatrics, Washington University in St. Louis, Missouri
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Vellimana AK, Zhou ML, Singh I, Aum DJ, Nelson JW, Harris GR, Athiraman U, Han BH, Zipfel GJ. Minocycline protects against delayed cerebral ischemia after subarachnoid hemorrhage via matrix metalloproteinase-9 inhibition. Ann Clin Transl Neurol 2017; 4:865-876. [PMID: 29296615 PMCID: PMC5740245 DOI: 10.1002/acn3.492] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2017] [Revised: 09/06/2017] [Accepted: 09/25/2017] [Indexed: 12/11/2022] Open
Abstract
Objective Delayed cerebral ischemia (DCI) is an independent risk factor for poor outcome after aneurysmal subarachnoid hemorrhage (SAH) and is multifactorial in etiology. While prior studies have suggested a role for matrix metalloproteinase-9 (MMP-9) in early brain injury after SAH, its contribution to the pathophysiology of DCI is unclear. Methods In the first experiment, wild-type (WT) and MMP-9-/- mice were subjected to sham or endovascular perforation SAH surgery. In separate experiments, WT and MMP-9-/-mice were administered vehicle or minocycline either pre- or post-SAH. All mice underwent assessment of multiple components of DCI including vasospasm, neurobehavioral function, and microvessel thrombosis. In another experiment, rabbits were subjected to sham or cisterna magna injection SAH surgery, and administered vehicle or minocycline followed by vasospasm assessment. Results MMP-9 expression and activity was increased after SAH. Genetic (MMP-9-/- mice) and pharmacological (pre-SAH minocycline administration) inhibition of MMP-9 resulted in decreased vasospasm and neurobehavioral deficits. A therapeutically feasible strategy of post-SAH administration of minocycline resulted in attenuation of multiple components of DCI. Minocycline administration to MMP-9-/- mice did not yield additional protection. Consistent with experiments in mice, both pre- and post-SAH administration of minocycline attenuated SAH-induced vasospasm in rabbits. Interpretation MMP-9 is a key player in the pathogenesis of DCI. The consistent attenuation of multiple components of DCI with both pre- and post-SAH administration of minocycline across different species and experimental models of SAH, combined with the excellent safety profile of minocycline in humans suggest that a clinical trial in SAH patients is warranted.
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Affiliation(s)
- Ananth K Vellimana
- Department of Neurological Surgery Washington University School of Medicine St. Louis Missouri
| | - Meng-Liang Zhou
- Department of Neurosurgery Jinling Hospital School of Medicine Nanjing University Nanjing Jiangsu Province China
| | - Itender Singh
- Department of Neurological Surgery Washington University School of Medicine St. Louis Missouri
| | - Diane J Aum
- Department of Neurological Surgery Washington University School of Medicine St. Louis Missouri
| | - James W Nelson
- Department of Neurological Surgery Washington University School of Medicine St. Louis Missouri
| | - Glenn R Harris
- Department of Neurological Surgery Washington University School of Medicine St. Louis Missouri
| | - Umeshkumar Athiraman
- Department of Anesthesiology Washington University School of Medicine St. Louis Missouri
| | - Byung H Han
- Department of Pharmacology A.T. Still University of Health Sciences Kirksville College of Osteopathic Medicine Kirksville Missouri
| | - Gregory J Zipfel
- Department of Neurological Surgery Washington University School of Medicine St. Louis Missouri
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Vellimana AK, Zhou ML, Singh I, Aum DJ, Nelson J, Han BH, Zipfel GJ. 379 Matrix Metalloproteinase-9. Neurosurgery 2017. [DOI: 10.1093/neuros/nyx417.379] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Vellimana AK, Aum DJ, Han BH, Gidday JM, Zipfel GJ. 100 SIRT1 Activation. Neurosurgery 2017. [DOI: 10.1093/neuros/nyx417.100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Aum D, Vellimana AK, Padovano A, Arias EJ, Athiraman U, Zipfel GJ. 383 Fever and Leukocytosis as a Predictor of DCI After SAH. Neurosurgery 2017. [DOI: 10.1093/neuros/nyx417.383] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Aum DJ, Vellimana AK, Singh I, Milner E, Nelson JW, Han BH, Zipfel GJ. A novel fluorescent imaging technique for assessment of cerebral vasospasm after experimental subarachnoid hemorrhage. Sci Rep 2017; 7:9126. [PMID: 28831103 PMCID: PMC5567362 DOI: 10.1038/s41598-017-09070-y] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2017] [Accepted: 07/21/2017] [Indexed: 12/22/2022] Open
Abstract
Various techniques have been developed to study changes in the cerebral vasculature in numerous neuropathological processes including subarachnoid hemorrhage (SAH). One of the most widely employed techniques uses India ink-gelatin casting, which presents numerous challenges due to its high viscosity, rapid solidification, and its impact on immunohistochemical analysis. To overcome these limitations, we developed a novel technique for assessing cerebral vasospasm using cerebrovascular perfusion with ROX, SE (5-Carboxy-X-Rhodamine, Succinimidyl Ester), a fluorescent labeling dye. We found that ROX SE perfusion achieves excellent delineation of the cerebral vasculature, was qualitatively and quantitatively superior to India ink-gelatin casting for the assessment of cerebral vasospasm, permits outstanding immunohistochemical examination of non-vasospasm components of secondary brain injury, and is a more efficient and cost-effective experimental technique. ROX SE perfusion is therefore a novel and highly useful technique for studying cerebrovascular pathology following experimental SAH.
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Affiliation(s)
- Diane J Aum
- Department of Neurological Surgery, Washington University School of Medicine, St Louis, MO, USA
| | - Ananth K Vellimana
- Department of Neurological Surgery, Washington University School of Medicine, St Louis, MO, USA
| | - Itender Singh
- Department of Neurological Surgery, Washington University School of Medicine, St Louis, MO, USA
| | - Eric Milner
- Department of Neurological Surgery, Washington University School of Medicine, St Louis, MO, USA
| | - James W Nelson
- Department of Neurological Surgery, Washington University School of Medicine, St Louis, MO, USA
| | - Byung Hee Han
- Department of Neurological Surgery, Washington University School of Medicine, St Louis, MO, USA.,Department of Pharmacology, A.T. Still University of Health Sciences, Kirksville, MO, USA
| | - Gregory J Zipfel
- Department of Neurological Surgery, Washington University School of Medicine, St Louis, MO, USA. .,Department of Neurology, Washington University School of Medicine, St Louis, MO, USA.
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Guzmán Pérez-Carrillo GJ, Owen C, Schwetye KE, McFarlane S, Vellimana AK, Mar S, Miller-Thomas MM, Shimony JS, Smyth MD, Benzinger TLS. The use of hippocampal volumetric measurements to improve diagnostic accuracy in pediatric patients with mesial temporal sclerosis. J Neurosurg Pediatr 2017; 19:720-728. [PMID: 28338446 DOI: 10.3171/2016.12.peds16335] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECTIVE Many patients with medically intractable epilepsy have mesial temporal sclerosis (MTS), which significantly affects their quality of life. The surgical excision of MTS lesions can result in marked improvement or even complete resolution of the epileptic episodes. Reliable radiological diagnosis of MTS is a clinical challenge. The purpose of this study was to evaluate the utility of volumetric mapping of the hippocampi for the identification of MTS in a case-controlled series of pediatric patients who underwent resection for medically refractory epilepsy, using pathology as a gold standard. METHODS A cohort of 57 pediatric patients who underwent resection for medically intractable epilepsy between 2005 and 2015 was evaluated. On pathological investigation, this group included 24 patients with MTS and 33 patients with non-MTS findings. Retrospective quantitative volumetric measurements of the hippocampi were acquired for 37 of these 57 patients. Two neuroradiologists with more than 10 years of experience who were blinded to the patients' MTS status performed the retrospective review of MR images. To produce the volumetric data, MR scans were parcellated and segmented using the FreeSurfer software suite. Hippocampal regions of interest were compared against an age-weighted local regression curve generated with data from the pediatric normal cohort. Standard deviations and percentiles of specific subjects were calculated. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were determined for the original clinical read and the expert readers. Receiver operating characteristic curves were generated for the methods of classification to compare results from the readers with the authors' results, and an optimal threshold was determined. From that threshold the sensitivity, specificity, PPV, and NPV were calculated for the volumetric analysis. RESULTS With the use of quantitative volumetry, a sensitivity of 72%, a specificity of 95%, a PPV of 93%, an NPV of 78%, and an area under the curve of 0.84 were obtained using a percentage difference of normalized hippocampal volume. The resulting specificity (95%) and PPV (93%) are superior to the original clinical read and to Reader A and Reader B's findings (range for specificity 74%-86% and for PPV 64%-71%). The sensitivity (72%) and NPV (78%) are comparable to Reader A's findings (73% and 81%, respectively) and are better than those of the original clinical read and of Reader B (sensitivity 45% and 63% and NPV 71% and 70%, respectively). CONCLUSIONS Volumetric measurement of the hippocampi outperforms expert readers in specificity and PPV, and it demonstrates comparable to superior sensitivity and NPV. Volumetric measurements can complement anatomical imaging for the identification of MTS, much like a computer-aided detection tool would. The implementation of this approach in the daily clinical workflow could significantly improve diagnostic accuracy.
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Affiliation(s)
| | - Christopher Owen
- Neuroradiology Section, Mallinckrodt Institute of Radiology, Washington University
| | | | - Spencer McFarlane
- Neuroradiology Section, Mallinckrodt Institute of Radiology, Washington University
| | - Ananth K Vellimana
- Department of Neurosurgery, Pediatric Division, St. Louis Children's Hospital/Washington University; and
| | - Soe Mar
- Department of Neurology, Division of Pediatric Neurology, Washington University School of Medicine, St. Louis, Missouri
| | | | - Joshua S Shimony
- Neuroradiology Section, Mallinckrodt Institute of Radiology, Washington University
| | - Matthew D Smyth
- Department of Neurosurgery, Pediatric Division, St. Louis Children's Hospital/Washington University; and
| | - Tammie L S Benzinger
- Neuroradiology Section, Mallinckrodt Institute of Radiology, Washington University
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Smyth MD, Vellimana AK, Asano E, Sood S. Corpus callosotomy-Open and endoscopic surgical techniques. Epilepsia 2017; 58 Suppl 1:73-79. [DOI: 10.1111/epi.13681] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/13/2016] [Indexed: 11/29/2022]
Affiliation(s)
- Matthew D. Smyth
- Department of Neurological Surgery; Washington University School of Medicine; St. Louis Missouri U.S.A
| | - Ananth K. Vellimana
- Department of Neurological Surgery; Washington University School of Medicine; St. Louis Missouri U.S.A
| | - Eishi Asano
- Department of Pediatrics; Wayne State University School of Medicine; Children's Hospital of Michigan; Detroit Michigan U.S.A
- Department of Neurology; Wayne State University School of Medicine; Children's Hospital of Michigan; Detroit Michigan U.S.A
| | - Sandeep Sood
- Department of Neurosurgery; Wayne State University School of Medicine; Children's Hospital of Michigan; Detroit Michigan U.S.A
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Abstract
OBJECTIVE Electrical status epilepticus of sleep (ESES) is a rare electrographic pattern associated with global regression, which is often poorly responsive to traditional epilepsy treatments and can have a devastating and permanent neurocognitive outcome. The authors analyzed clinical, electroencephalographic, and neuropsychological outcomes in 9 patients with refractory ESES treated with functional hemispherotomy to illustrate the wide clinical spectrum associated with the disease and explore the role of hemispherotomy in its treatment. METHODS During the period between 2003 and 2015, 80 patients underwent hemispherotomy at the authors' institution. Video electroencephalography (EEG) reports were reviewed for ESES or continuous spikes and waves during sleep (CSWS). Patients with preoperative ESES (> 85% slow-wave sleep occupied by spike waves), a unilateral structural lesion amenable to surgery, and more than 6 months of follow-up data were included in the analysis. Clinical data, EEG recordings, neuropsychological testing, and parental and clinician reports were retrospectively reviewed. RESULTS Nine patients were eligible for study inclusion. Age at seizure onset ranged from birth to 4.2 years (mean 1.9 years), age at ESES diagnosis ranged from 3.5 to 8.8 years (mean 6.0 years), and age at hemispherotomy ranged from 3.7 to 11.5 years (mean 6.8 years). All patients had drug-resistant epilepsy. The duration of epilepsy prior to hemispherotomy ranged from 2.7 to 8.9 years (mean ± SD, 5.0 ± 2.2 years). Engel Class I seizure outcome was observed in all 9 children, with a mean follow-up of 3.0 years (range 0.5-6.1 years). Hemispherotomy terminated ESES in 6 of 6 patients with available postoperative sleep EEG. All children had preoperative neuropsychological impairments. Developmental regression was halted postoperatively, but none of the children returned to their original pre-ESES baseline. Four children demonstrated academic gains, 2 of whom transitioned to mainstream classes. CONCLUSIONS Children with drug-resistant ESES and a unilateral structural lesion should be evaluated for hemispherotomy as they may experience the cessation of seizures, termination of ESES, and improvement in neuropsychological status.
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Affiliation(s)
| | - Jennifer Strahle
- Neurological Surgery, Washington University School of Medicine, St. Louis, Missouri
| | - Ananth K Vellimana
- Neurological Surgery, Washington University School of Medicine, St. Louis, Missouri
| | - David D Limbrick
- Neurological Surgery, Washington University School of Medicine, St. Louis, Missouri
| | - Matthew D Smyth
- Neurological Surgery, Washington University School of Medicine, St. Louis, Missouri
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Washington CW, Derdeyn CP, Dhar R, Arias EJ, Chicoine MR, Cross DT, Dacey RG, Han BH, Moran CJ, Rich KM, Vellimana AK, Zipfel GJ. A Phase I proof-of-concept and safety trial of sildenafil to treat cerebral vasospasm following subarachnoid hemorrhage. J Neurosurg 2015; 124:318-27. [PMID: 26314998 DOI: 10.3171/2015.2.jns142752] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
OBJECTIVE Studies show that phosphodiesterase-V (PDE-V) inhibition reduces cerebral vasospasm (CVS) and improves outcomes after experimental subarachnoid hemorrhage (SAH). This study was performed to investigate the safety and effect of sildenafil (an FDA-approved PDE-V inhibitor) on angiographic CVS in SAH patients. METHODS A2-phase, prospective, nonrandomized, human trial was implemented. Subarachnoid hemorrhage patients underwent angiography on Day 7 to assess for CVS. Those with CVS were given 10 mg of intravenous sildenafil in the first phase of the study and 30 mg in the second phase. In both, angiography was repeated 30 minutes after infusion. Safety was assessed by monitoring neurological examination findings and vital signs and for the development of adverse reactions. For angiographic assessment, in a blinded fashion, pre- and post-sildenafil images were graded as "improvement" or "no improvement" in CVS. Unblinded measurements were made between pre- and post-sildenafil angiograms. RESULTS Twelve patients received sildenafil; 5 patients received 10 mg and 7 received 30 mg. There were no adverse reactions. There was no adverse effect on heart rate or intracranial pressure. Sildenafil resulted in a transient decline in mean arterial pressure, an average of 17% with a return to baseline in an average of 18 minutes. Eight patients (67%) were found to have a positive angiographic response to sildenafil, 3 (60%) in the low-dose group and 5 (71%) in the high-dose group. The largest degree of vessel dilation was an average of 0.8 mm (range 0-2.1 mm). This corresponded to an average percentage increase in vessel diameter of 62% (range 0%-200%). CONCLUSIONS The results from this Phase I safety and proof-of-concept trial assessing the use of intravenous sildenafil in patients with CVS show that sildenafil is safe and well tolerated in the setting of SAH. Furthermore, the angiographic data suggest that sildenafil has a positive impact on human CVS.
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Affiliation(s)
- Chad W Washington
- Departments of 1 Neurological Surgery.,Radiology, Washington University School of Medicine, Saint Louis, Missouri
| | - Colin P Derdeyn
- Departments of 1 Neurological Surgery.,Radiology, Washington University School of Medicine, Saint Louis, Missouri
| | | | | | | | - DeWitte T Cross
- Departments of 1 Neurological Surgery.,Radiology, Washington University School of Medicine, Saint Louis, Missouri
| | | | | | - Christopher J Moran
- Departments of 1 Neurological Surgery.,Radiology, Washington University School of Medicine, Saint Louis, Missouri
| | - Keith M Rich
- Departments of 1 Neurological Surgery.,Radiology, Washington University School of Medicine, Saint Louis, Missouri
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Milner E, Zhou ML, Johnson AW, Vellimana AK, Greenberg JK, Holtzman DM, Han BH, Zipfel GJ. Cerebral amyloid angiopathy increases susceptibility to infarction after focal cerebral ischemia in Tg2576 mice. Stroke 2014; 45:3064-9. [PMID: 25190447 DOI: 10.1161/strokeaha.114.006078] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
BACKGROUND AND PURPOSE We and others have shown that soluble amyloid β-peptide (Aβ) and cerebral amyloid angiopathy (CAA) cause significant cerebrovascular dysfunction in mutant amyloid precursor protein (APP) mice, and that these deficits are greater in aged APP mice having CAA compared with young APP mice lacking CAA. Amyloid β-peptide in young APP mice also increases infarction after focal cerebral ischemia, but the impact of CAA on ischemic brain injury is unknown. METHODS To determine this, we assessed cerebrovascular reactivity, cerebral blood flow (CBF), and extent of infarction and neurological deficits after transient middle cerebral artery occlusion in aged APP mice having extensive CAA versus young APP mice lacking CAA (and aged-matched littermate controls). RESULTS We found that aged APP mice have more severe cerebrovascular dysfunction that is CAA dependent, have greater CBF compromise during and immediately after middle cerebral artery occlusion, and develop larger infarctions after middle cerebral artery occlusion. CONCLUSIONS These data indicate CAA induces a more severe form of cerebrovascular dysfunction than amyloid β-peptide alone, leading to intra- and postischemic CBF deficits that ultimately exacerbate cerebral infarction. Our results shed mechanistic light on human studies identifying CAA as an independent risk factor for ischemic brain injury.
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Affiliation(s)
- Eric Milner
- From the Department of Neurological Surgery (E.M., M.-L.Z., A.W.J., A.K.V., J.K.G., B.H.H., G.J.Z.), Program in Neuroscience (E.M.), Department of Neurology (D.M.H., G.J.Z.), Department of Developmental Biology (D.M.H.), and Hope Center for Neurological Disorders (D.M.H., B.H.H., G.J.Z.), Washington University School of Medicine, St. Louis, MO
| | - Meng-Liang Zhou
- From the Department of Neurological Surgery (E.M., M.-L.Z., A.W.J., A.K.V., J.K.G., B.H.H., G.J.Z.), Program in Neuroscience (E.M.), Department of Neurology (D.M.H., G.J.Z.), Department of Developmental Biology (D.M.H.), and Hope Center for Neurological Disorders (D.M.H., B.H.H., G.J.Z.), Washington University School of Medicine, St. Louis, MO
| | - Andrew W Johnson
- From the Department of Neurological Surgery (E.M., M.-L.Z., A.W.J., A.K.V., J.K.G., B.H.H., G.J.Z.), Program in Neuroscience (E.M.), Department of Neurology (D.M.H., G.J.Z.), Department of Developmental Biology (D.M.H.), and Hope Center for Neurological Disorders (D.M.H., B.H.H., G.J.Z.), Washington University School of Medicine, St. Louis, MO
| | - Ananth K Vellimana
- From the Department of Neurological Surgery (E.M., M.-L.Z., A.W.J., A.K.V., J.K.G., B.H.H., G.J.Z.), Program in Neuroscience (E.M.), Department of Neurology (D.M.H., G.J.Z.), Department of Developmental Biology (D.M.H.), and Hope Center for Neurological Disorders (D.M.H., B.H.H., G.J.Z.), Washington University School of Medicine, St. Louis, MO
| | - Jacob K Greenberg
- From the Department of Neurological Surgery (E.M., M.-L.Z., A.W.J., A.K.V., J.K.G., B.H.H., G.J.Z.), Program in Neuroscience (E.M.), Department of Neurology (D.M.H., G.J.Z.), Department of Developmental Biology (D.M.H.), and Hope Center for Neurological Disorders (D.M.H., B.H.H., G.J.Z.), Washington University School of Medicine, St. Louis, MO
| | - David M Holtzman
- From the Department of Neurological Surgery (E.M., M.-L.Z., A.W.J., A.K.V., J.K.G., B.H.H., G.J.Z.), Program in Neuroscience (E.M.), Department of Neurology (D.M.H., G.J.Z.), Department of Developmental Biology (D.M.H.), and Hope Center for Neurological Disorders (D.M.H., B.H.H., G.J.Z.), Washington University School of Medicine, St. Louis, MO
| | - Byung Hee Han
- From the Department of Neurological Surgery (E.M., M.-L.Z., A.W.J., A.K.V., J.K.G., B.H.H., G.J.Z.), Program in Neuroscience (E.M.), Department of Neurology (D.M.H., G.J.Z.), Department of Developmental Biology (D.M.H.), and Hope Center for Neurological Disorders (D.M.H., B.H.H., G.J.Z.), Washington University School of Medicine, St. Louis, MO
| | - Gregory J Zipfel
- From the Department of Neurological Surgery (E.M., M.-L.Z., A.W.J., A.K.V., J.K.G., B.H.H., G.J.Z.), Program in Neuroscience (E.M.), Department of Neurology (D.M.H., G.J.Z.), Department of Developmental Biology (D.M.H.), and Hope Center for Neurological Disorders (D.M.H., B.H.H., G.J.Z.), Washington University School of Medicine, St. Louis, MO.
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Vellimana AK, Daniels DJ, Shah MN, Zipfel GJ, Lanzino G. Dural arteriovenous fistulas associated with benign meningeal tumors. Acta Neurochir (Wien) 2014; 156:535-44. [PMID: 24363145 DOI: 10.1007/s00701-013-1946-z] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2013] [Accepted: 11/08/2013] [Indexed: 11/29/2022]
Abstract
BACKGROUND Dural arteriovenous fistulas (dAVFs) are usually idiopathic lesions. While individual case reports have documented the occurrence of dAVFs in conjunction with benign meningeal tumors, a detailed characterization of this association is lacking. The objective of this study was to critically examine the relationship between benign meningeal tumors and dAVFs. METHODS We performed a retrospective review of records at two institutions, identified patients with coexisting benign meningeal tumors and dAVFs at the time of clinical presentation, and examined various clinical, anatomical and radiographic characteristics. RESULTS Ten patients (4.6%) had coexisting benign meningeal tumors and dAVFs. The most common tumor was meningioma (90%). Nine patients were symptomatic: five from tumor, three from dAVF, and one from both tumor and dAVF. All dAVFs were related to the meningeal tumor. CONCLUSIONS Benign meningeal tumors may be associated with dAVFs that are either in direct anatomical relation to the tumor or in distant anatomical locations. The increased propensity for development of dAVFs in patients with benign meningeal tumors may be due to multiple factors. Due to this association, additional imaging to exclude dAVFs could be considered in patients with meningeal tumors if exuberant vessels or flow voids are identified on routinely obtained magnetic resonance imaging scans.
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Affiliation(s)
- Ananth K Vellimana
- Department of Neurological Surgery, Washington University School of Medicine, 660 S. Euclid Ave, Campus Box 8057, Saint Louis, MO, 63108, USA,
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Vellimana AK, Yarbrough CK, Blackburn S, Strom RG, Pilgram TK, Lee JM, Grubb RL, Rich KM, Chicoine MR, Dacey RG, Derdeyn CP, Zipfel GJ. Intravenous tissue-type plasminogen activator therapy is an independent risk factor for symptomatic intracerebral hemorrhage after carotid endarterectomy. Neurosurgery 2014; 74:254-61. [PMID: 24335814 PMCID: PMC4097004 DOI: 10.1227/neu.0000000000000261] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Carotid endarterectomy (CEA) for symptomatic carotid artery stenosis and intravenous tissue-type plasminogen activator (IV-tPA) for acute ischemic stroke are proven therapies; however, the safety of CEA in stroke patients who recently received IV-tPA has not been established. OBJECTIVE To evaluate the safety of CEA in stroke patients who recently received IV-tPA. METHODS A retrospective review of patients who underwent CEA for symptomatic carotid artery stenosis was performed. The primary end point was postoperative symptomatic intracerebral hemorrhage (sICH). A univariate analysis of potential risk factors for sICH, including IV-tPA therapy, timing of CEA, degree of stenosis, and stroke severity, was performed. Factors with a value of P < .1 on univariate analysis were tested further. RESULTS Among 142 patients, 3 suffered sICH after CEA: 2 of 11 patients treated with IV-tPA (18.2%) and 1 of 131 patients not treated with IV-tPA (0.8%). Both IV-tPA patients suffering sICH underwent CEA within 3 days of tPA administration. On univariate analysis, IV-tPA (P = .02), female sex (P = .09), shorter time between ischemic event and CEA (P = .06), and lower mean arterial pressure during the first 48 hours of admission (P = .08) were identified as risk factors for sICH. On multivariate analysis, IV-tPA was the only significant risk factor (P = .002 by stepwise logistic regression; P = .03 by nominal logistic regression). CONCLUSION This study indicates that IV-tPA is an independent risk factor for sICH after CEA. This suggests that CEA should be pursued cautiously in patients who recently received IV-tPA. Early surgery may be associated with an increased risk for sICH. ABBREVIATIONS CEA, carotid endarterectomyIV-tPA, intravenous recombinant tissue-type plasminogen activatorMAP, mean arterial pressureNASCET, North American Symptomatic Carotid Endarterectomy TrialNIHSS, National Institutes of Health Stroke ScaleNINDS, National Institute of Neurological Disorders and StrokesICH, symptomatic intracerebral hemorrhageTIA, transient ischemic attack.
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Affiliation(s)
- Ananth K. Vellimana
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Chester K. Yarbrough
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Spiros Blackburn
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, Missouri, USA
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Russell G. Strom
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Thomas K. Pilgram
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Jin-Moo Lee
- Department of Neurology, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Robert L. Grubb
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Keith M. Rich
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Michael R. Chicoine
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Ralph G. Dacey
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Colin P. Derdeyn
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, Missouri, USA
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, Missouri, USA
- Department of Neurology, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Gregory J. Zipfel
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, Missouri, USA
- Department of Neurology, Washington University School of Medicine, St. Louis, Missouri, USA
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Abstract
OBJECT In this paper the authors' goal was to review the clinical features and outcome of patients with intracranial dural arteriovenous fistulas (DAVFs) who presented with hemorrhage. METHODS A retrospective study of 28 patients with DAVFs who presented with intracranial hemorrhage to 2 separate institutions was performed. The information reviewed included clinical presentation, location and size of hemorrhage, angiographic features, treatment, and clinical and radiologically documented outcomes. Clinical and radiological follow-up were available in 27 of 28 patients (mean follow-up 17 months). RESULTS The vast majority of patients were male (86%), and the most common presenting symptom was sudden-onset headache. All DAVFs had cortical venous drainage, and about one-third were associated with a venous varix. The most common location was tentorial (75%). Treatment ranged from endovascular (71%), surgical (43%), Gamma Knife surgery (4%), or a combination of modalities. The majority of fistulas (75%) were completely obliterated, and most patients experienced excellent clinical outcome (71%, modified Rankin Scale score of 0 or 1). There were no complications in this series. CONCLUSIONS Case series, including the current one, suggest that the vast majority of patients who present with intracranial hemorrhage from a DAVF are male. The most common location for DAVFs presenting with hemorrhage is tentorial. Excellent outcomes are achieved with individualized treatment, which includes various therapeutic strategies alone or in combination. Despite the hemorrhagic presentation, almost two-thirds of patients experience a full recovery with no or minimal residual symptoms.
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Affiliation(s)
- David J Daniels
- Department of Neurological Surgery, Mayo Clinic, Rochester, Minnesota 55905, USA
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Lusis EA, Vellimana AK, Ray WZ, Chicoine MR, Jost SC. Transient Obstructive Hydrocephalus due to Intraventricular Hemorrhage: A Case Report and Review of Literature. J Clin Neurol 2013; 9:192-5. [PMID: 23894243 PMCID: PMC3722471 DOI: 10.3988/jcn.2013.9.3.192] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2012] [Revised: 07/09/2012] [Accepted: 07/09/2012] [Indexed: 11/17/2022] Open
Abstract
Background Acute transient obstructive hydrocephalus is rare in adults. We describe a patient with intraventricular hemorrhage (IVH) who experienced the delayed development of acute transient hydrocephalus. Case Report A 33-year-old man with a previously diagnosed Spetzler-Martin Grade 5 arteriovenous malformation presented with severe headache, which was found to be due to IVH. Forty hours after presentation he developed significant obstructive hydrocephalus due to the thrombus migrating to the cerebral aqueduct, and a ventriculostomy placement was planned. However, shortly thereafter his headache began to improve spontaneously. Within 4 hours after onset the headache had completely resolved, and an interval head CT scan revealed resolution of hydrocephalus. Conclusions In patients with IVH, acute obstructive hydrocephalus can develop at any time after the ictus. Though a delayed presentation of acute but transient obstructive hydrocephalus is unusual, it is important to be aware of this scenario and ensure that deterioration secondary to thrombus migration and subsequent obstructive hydrocephalus do not occur.
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Affiliation(s)
- Eriks A Lusis
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, MO, USA
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Vellimana AK, Recinos VR, Hwang L, Fowers KD, Li KW, Zhang Y, Okonma S, Eberhart CG, Brem H, Tyler BM. Combination of paclitaxel thermal gel depot with temozolomide and radiotherapy significantly prolongs survival in an experimental rodent glioma model. J Neurooncol 2012; 111:229-36. [PMID: 23224713 DOI: 10.1007/s11060-012-1014-1] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2012] [Accepted: 11/22/2012] [Indexed: 11/28/2022]
Abstract
OncoGel™ incorporates paclitaxel, a mitotic inhibitor, into ReGel™, a thermosensitive gel depot system to provide local delivery, enhance efficacy and limit systemic toxicity. In previous studies the alkylating agent temozolomide (TMZ) incorporated into a polymer, pCPP:SA, also for local delivery, and OncoGel were individually shown to increase efficacy in a rat glioma model. We investigated the effects of OncoGel with oral TMZ or locally delivered TMZ polymer, with and without radiotherapy (XRT) in rats with intracranial gliosarcoma. Eighty-nine animals were intracranially implanted with a 9L gliosarcoma tumor and divided into 12 groups that received various combinations of 4 treatment options; OncoGel 6.3 mg/ml (Day 0), 20 Gy XRT (Day 5), 50 % TMZ-pCPP:SA (Day 5), or oral TMZ (50 mg/kg, qd, Days 5-9). Animals were followed for survival for 120 days. Median survival for untreated controls, XRT alone or oral TMZ alone was 15, 19 and 28 days, respectively. OncoGel 6.3 or TMZ polymer alone extended median survival to 33 and 35 days, respectively (p = 0.0005; p < 0.0001, vs. untreated controls) with 50 % living greater than 120 days (LTS) in both groups. Oral TMZ/XRT extended median survival to 36 days (p = 0.0002), with no LTS. The group that received OncoGel and Oral TMZ did not reach median survival with 57 % LTS (p = 0.0002). All other combination groups [OncoGel/XRT], [TMZ polymer/XRT], [OncoGel/TMZ polymer], [OncoGel/TMZ polymer/XRT], and [OncoGel/oral TMZ/XRT] yielded greater than 50 % LTS (p < 0.0001 for each combination as compared to controls), therefore median survival was not reached. OncoGel/TMZ polymer and OncoGel/oral TMZ/XRT had 100 % LTS (p < 0.0001 and p = 0.0001 vs. oral TMZ/XRT, respectively). These results indicate that OncoGel given locally with oral or locally delivered TMZ and/or XRT significantly increased the number of LTS and improved median survival compared to oral TMZ and XRT given alone or in combination in a rodent intracranial gliosarcoma model.
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Affiliation(s)
- Ananth K Vellimana
- Department of Neurosurgery, Johns Hopkins University School of Medicine, 1550 Orleans Street CRB2 2M41, Baltimore, MD 21231, USA
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Vellimana AK, Kadkhodayan Y, Rich KM, Cross DT, Moran CJ, Zazulia AR, Lee JM, Chicoine MR, Dacey RG, Derdeyn CP, Zipfel GJ. Symptomatic patients with intraluminal carotid artery thrombus: outcome with a strategy of initial anticoagulation. J Neurosurg 2012; 118:34-41. [PMID: 23061393 DOI: 10.3171/2012.9.jns12406] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECT The aim of this study was to define the optimal treatment for patients with symptomatic intraluminal carotid artery thrombus (ICAT). METHODS The authors performed a retrospective chart review of patients who had presented with symptomatic ICAT at their institution between 2001 and 2011. RESULTS Twenty-four patients (16 males and 8 females) with ICAT presented with ischemic stroke (18 patients) or transient ischemic attack ([TIA], 6 patients). All were initially treated using anticoagulation with or without antiplatelet drugs. Eight of these patients had no or only mild carotid artery stenosis on initial angiography and were treated with medical management alone. The remaining 16 patients had moderate or severe carotid stenosis on initial angiography; of these, 10 underwent delayed revascularization (8 patients, carotid endarterectomy [CEA]; 2 patients, angioplasty and stenting), 2 refused revascularization, and 4 were treated with medical therapy alone. One patient had multiple TIAs despite medical therapy and eventually underwent CEA; the remaining 23 patients had no TIAs after treatment. No patient suffered ischemic or hemorrhagic stroke while on anticoagulation therapy, either during the perioperative period or in the long-term follow-up; 1 patient died of an unrelated condition. The mean follow-up was 16.4 months. CONCLUSIONS Results of this study suggest that initial anticoagulation for symptomatic ICAT leads to a low rate of recurrent ischemic events and that carotid revascularization, if indicated, can be safely performed in a delayed manner.
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Affiliation(s)
- Ananth K Vellimana
- Department of Neurological Surgery, Washington University School of Medicine in St. Louis, Missouri 63110, USA
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Vellimana AK, Ford AL, Lee JM, Derdeyn CP, Zipfel GJ. Symptomatic intracranial arterial disease: incidence, natural history, diagnosis, and management. Neurosurg Focus 2012; 30:E14. [PMID: 21631215 DOI: 10.3171/2011.3.focus1138] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Symptomatic intracranial arterial disease is associated with a high rate of recurrent ischemic events. The management of this condition is controversial, with some advocating medical therapy as a sole means of treatment and others recommending endovascular therapy in addition to best medical management. In rare cases, surgical intervention is considered. A thorough review of the available literature was performed, and treatment recommendations based on these data are provided.
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Affiliation(s)
- Ananth K Vellimana
- Department of Neurological Surgery, Washington University School of Medicine, St. Louis, Missouri, USA
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Han BH, Zhou ML, Vellimana AK, Milner E, Kim DH, Greenberg JK, Chu W, Mach RH, Zipfel GJ. Resorufin analogs preferentially bind cerebrovascular amyloid: potential use as imaging ligands for cerebral amyloid angiopathy. Mol Neurodegener 2011; 6:86. [PMID: 22192811 PMCID: PMC3259047 DOI: 10.1186/1750-1326-6-86] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2011] [Accepted: 12/22/2011] [Indexed: 12/17/2022] Open
Abstract
Background Cerebral amyloid angiopathy (CAA) is characterized by deposition of fibrillar amyloid β (Aβ) within cerebral vessels. It is commonly seen in the elderly and almost universally present in patients with Alzheimer's Disease (AD). In both patient populations, CAA is an independent risk factor for lobar hemorrhage, ischemic stroke, and dementia. To date, definitive diagnosis of CAA requires obtaining pathological tissues via brain biopsy (which is rarely clinically indicated) or at autopsy. Though amyloid tracers labeled with positron-emitting radioligands such as [11C]PIB have shown promise for non-invasive amyloid imaging in AD patients, to date they have been unable to clarify whether the observed amyloid load represents neuritic plaques versus CAA due in large part to the low resolution of PET imaging and the almost equal affinity of these tracers for both vascular and parenchymal amyloid. Therefore, the development of a precise and specific non-invasive technique for diagnosing CAA in live patients is desired. Results We found that the phenoxazine derivative resorufin preferentially bound cerebrovascular amyloid deposits over neuritic plaques in the aged Tg2576 transgenic mouse model of AD/CAA, whereas the congophilic amyloid dye methoxy-X34 bound both cerebrovascular amyloid deposits and neuritic plaques. Similarly, resorufin-positive staining was predominantly noted in fibrillar Aβ-laden vessels in postmortem AD brain tissues. Fluorescent labeling and multi-photon microscopy further revealed that both resorufin- and methoxy-X34-positive staining is colocalized to the vascular smooth muscle (VSMC) layer of vessel segments that have severe disruption of VSMC arrangement, a characteristic feature of CAA. Resorufin also selectively visualized vascular amyloid deposits in live Tg2576 mice when administered topically, though not systemically. Resorufin derivatives with chemical modification at the 7-OH position of resorufin also displayed a marked preferential binding affinity for CAA, but with enhanced lipid solubility that indicates their use as a non-invasive imaging tracer for CAA is feasible. Conclusions To our knowledge, resorufin analogs are the fist class of amyloid dye that can discriminate between cerebrovascular and neuritic forms of amyloid. This unique binding selectivity suggests that this class of dye has great potential as a CAA-specific amyloid tracer that will permit non-invasive detection and quantification of CAA in live patients.
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Affiliation(s)
- Byung Hee Han
- Department of Neurological Surgery, Washington University School of Medicine, St, Louis, MO 63110, USA.
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Washington CW, Vellimana AK, Zipfel GJ, Dacey RG. The current surgical management of intracranial aneurysms. J Neurosurg Sci 2011; 55:211-231. [PMID: 21968585] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
For more than two decades, surgical clipping of ruptured intracranial aneurysms was considered the stan-dard of care. However, as technology improved, a new treatment option was developed, endovascular emoblization. The treatment of cerebral aneurysms, is now in an era where deciding when to clip versus coil can be difficult. Today's cerebrovascular specialist must consider a multitude of factors when developing the best treatment strategy for an individual patient. Optimal management requires a thorough understanding of the natural history of aneurysms as well as risks and benefits related to the different treatment modalities. The purpose of this article is not to proclaim one treatment better than the other, but rather to provide the reader with an up-to-date, comprehensive insight into the management of cerebral aneurysms. We will review data regarding the natural history of aneurysms along with the effectiveness of both surgical clipping and endovascular embolization. We will further discuss our current management strategy for some of the most common aneurysms encountered. The successful treatment of intracranial aneurysms requires a multidisciplinary approach, where surgery and endovascular therapies are viewed as complimentary instead of competing.
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Affiliation(s)
- C W Washington
- Department of Neurological Surgery, Washington University School of Medicine, St Louis, MO, USA
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Vellimana AK, Milner E, Azad TD, Harries MD, Zhou ML, Gidday JM, Han BH, Zipfel GJ. Endothelial nitric oxide synthase mediates endogenous protection against subarachnoid hemorrhage-induced cerebral vasospasm. Stroke 2011; 42:776-82. [PMID: 21317271 DOI: 10.1161/strokeaha.110.607200] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
BACKGROUND AND PURPOSE Vasospasm-induced delayed cerebral ischemia remains a major source of morbidity in patients with aneurysmal subarachnoid hemorrhage (SAH). We hypothesized that activating innate neurovascular protective mechanisms by preconditioning (PC) may represent a novel therapeutic approach against SAH-induced vasospasm and neurological deficits and, secondarily, that the neurovascular protection it provides is mediated by endothelial nitric oxide synthase (eNOS). METHODS Wild-type mice were subjected to hypoxic PC or normoxia followed 24 hours later by SAH. Neurological function was analyzed daily; vasospasm was assessed on post-surgery Day 2. Nitric oxide availability, eNOS expression, and eNOS activity were also assessed. In a separate experiment, wild-type and eNOS-null mice were subjected to hypoxic PC or normoxia followed by SAH and assessed for vasospasm and neurological deficits. RESULTS PC nearly completely prevented SAH-induced vasospasm and neurological deficits. It also prevented SAH-induced reduction in nitric oxide availability and increased eNOS activity in mice with and without SAH. PC-induced protection against vasospasm and neurological deficits was lost in wild-type mice treated with the nitric oxide synthase inhibitor N(G)-nitro-l-arginine methyl ester and in eNOS-null mice. CONCLUSIONS Endogenous protective mechanisms against vasospasm exist, are powerful, and can be induced by PC. eNOS-derived nitric oxide is a critical mediator of PC-induced neurovascular protection. These data provide strong "proof-of-principle" evidence that PC represents a promising new strategy to reduce vasospasm and delayed cerebral ischemia after SAH.
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Affiliation(s)
- Ananth K Vellimana
- Department of Neurological Surgery, Washington University School of Medicine, 660 S Euclid Avenue, St Louis, MO 63110, USA
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Pandey A, Patni N, Sarangi S, Singh M, Sharma K, Vellimana AK, Patra S. Association of exclusive smokeless tobacco consumption with hypertension in an adult male rural population of India. Tob Induc Dis 2009; 5:15. [PMID: 19930693 PMCID: PMC2789706 DOI: 10.1186/1617-9625-5-15] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2009] [Accepted: 11/24/2009] [Indexed: 02/04/2023] Open
Abstract
Introduction Tobacco consumption is a major source of mortality and morbidity in India . Prevalence of smokeless tobacco (ST) consumption in India is around 20%. Studies have shown increased prevalence of cardiovascular disease risk factors and an increased incidence of adverse cardiovascular events among the ST consumers. This is a cross-sectional study done to look into the association of exclusive smokeless tobacco consumption with hypertension, in an adult male rural population of north India. Methods All male residents of a village in north India above 15 years of age, who did not have any acute or chronic morbidity were included after taking an informed consent. Subjects were interviewed regarding their demographic profile, socioeconomic status and tobacco consuming habits. Current smokeless tobacco user was defined as one who has ever consumed tobacco orally in past 1 month. Blood pressure of the subjects was also recorded. Cut offs used for systolic and diastolic hypertension were 140 mm hg and 90 mm Hg respectively. Results 443 subjects were included in the study. Prevalence of exclusive ST users was 21% while 19.4% consumed both forms and 26.6% did not take any form of tobacco. Mean systolic and diastolic BP were significantly higher in exclusive ST users(systolic BP=139.2+17.4,diastolic BP = 86.8+11.5)as compared to the non users(systolic BP= 135.7+18.8 , diastolic BP= 82.6 +11.5; p value < 0.05). The prevalence of diastolic hypertension was significantly higher in exclusive ST users as compared to non users ( 40.9%, 22.9% ;p value = 0.01) . The OR for diastolic hypertension in male ST users was 2.3( 95% C.I. = 1.3-4.3). Prevalence of systolic hypertension was higher in exclusive ST users too though this was not statistically significant (43%,36.4%;p value = 0.39.). Conclusion ST consumption is associated with increased prevalence of high BP in the adult male rural population.This is an indicator of increased predisposition to major adverse cardiac events later in their life time. Prevention of ST consumption could be an important intervention in preventing the ongoing upswing in prevalence of chronic heart disease.
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Affiliation(s)
- Ambarish Pandey
- Centre for Community Medicine, All India Institute of Medical Sciences, New Delhi, India.
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Sciubba DM, Noggle JC, Vellimana AK, Alosh H, McGirt MJ, Gokaslan ZL, Wolinsky JP. Radiographic and clinical evaluation of free-hand placement of C-2 pedicle screws. J Neurosurg Spine 2009; 11:15-22. [DOI: 10.3171/2009.3.spine08166] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Object
Stabilization of the cervical spine can be challenging when instrumentation involves the axis. Fixation with C1–2 transarticular screws combined with posterior wiring and bone graft placement has yielded excellent fusion rates, but the technique is technically demanding and places the vertebral arteries (VAs) at risk. Placement of screws in the pars interarticularis of C-2 as described by Harms and Melcher has allowed rigid fixation with greater ease and theoretically decreases the risk to the VA. However, fluoroscopy is suggested to avoid penetration laterally, medially, and superiorly to avoid damage to the VA, spinal cord, and C1–2 joint, respectively. The authors describe how, after meticulous dissection of the C-2 pars interarticularis, such screws can be placed accurately and safely without the use of fluoroscopy.
Methods
Prospective follow-up was performed in 55 consecutive patients who underwent instrumented fusion of C-2 by a single surgeon. The causes of spinal instability and type and extent of instrumentation were documented. All patients underwent preoperative CT or MR imaging scans to determine the suitability of C-2 screw placement. Intraoperatively, screws were placed following dissection of the posterior pars interarticularis. Postoperative CT scans were performed to determine the extent of cortical breach. Patients underwent clinical follow-up, and complications were recorded as vascular or neurological. A CT-based grading system was created to characterize such breaches objectively by location and magnitude via percentage of screw diameter beyond the cortical edge (0 = none; I = < 25% of screw diameter; II = 26–50%; III = 51–75%; IV = 76–100%).
Results
One-hundred consecutive screws were placed in the pedicle of the axis by a single surgeon using external landmarks only. In 10 cases, only 1 screw was placed because of a preexisting VA anatomy or bone abnormality noted preoperatively. In no case was screw placement aborted because of complications noted during drilling. Early complications occurred in 2 patients and were limited to 1 wound infection and 1 transient C-2 radiculopathy. There were 15 total breaches (15%), 2 of which occurred in the same patient. Twelve breaches were lateral (80%), and 3 were superior (20%). There were no medial breaches. The magnitude of the breach was classified as I in 10 cases (66.7% of breaches), II in 3 cases (20% of breaches), III in 1 case (6.7%), and IV in 1 case (6.7%).
Conclusions
Free-hand placement of screws in the C-2 pedicle can be done safely and effectively without the use of intraoperative fluoroscopy or navigation when the pars interarticularis/pedicle is assessed preoperatively with CT or MR imaging and found to be suitable for screw placement. When breaches do occur, they are overwhelmingly lateral in location, breach < 50% of the screw diameter, and in the authors' experience, are not clinically significant.
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