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Leonardo Rangel-Castilla, Hussain Shallwani and Adnan H. Siddiqui

Transvenous embolization (TE) has been increasingly applied for arteriovenous malformation (AVM) treatment. Transient cardiac standstill (TCS) has been described in cerebrovascular surgery but is uncommon for endovascular embolization. The authors present a patient with a ruptured thalamic AVM in whom both techniques were applied simultaneously. Surgery was considered, but the patient refused. Transarterial embolization was performed with an incomplete result. The deep-seated draining vein provided sole access to the AVM. A microcatheter was advanced into the draining vein. Under TCS, achieved with rapid ventricular pacing, complete AVM embolization was obtained. One-year magnetic resonance imaging and cerebral angiography demonstrated no residual AVM.

The video can be found here: https://youtu.be/CAzb9md_xBU.

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Elad I. Levy, Adnan H. Siddiqui and L. Nelson Hopkins

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Giuseppe Lanzino and Pietro Ivo D'Urso

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Leonardo Rangel-Castilla, Hakeem J. Shakir and Adnan H. Siddiqui

The ability to traverse an anatomically challenging and complex arch is paramount to the success of any neuroendovascular procedure. With age, the aortic arch becomes elongated, calcified, and less compliant. The authors present the initial experience with a multiple parallel guidewire system (ZigiWire Mode 3) for catheterization through a complex tortuous aortic arch to access extracranial vessels. The ZigiWire is an organized guidewire system that uses consecutive delivery of 3 small-diameter (0.014-inch) guidewires that are progressively advanced in parallel to secure support-wire access. The authors have found it useful in situations in which traditional methods for great-vessel access have failed. Moreover, the progressive construction of a large wire from smaller wires prevents “kickback” force from a single larger guidewire, allowing stable distal access. The authors have been able to advance different diagnostic and guide catheters over the ZigiWire. This guidewire has allowed them to successfully complete neuroendovascular procedures in patients who were previously considered unsuitable for the procedure because of tortuous vascular access.

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Peter Kan, Maxim Mokin, Adib A. Abla, Jorge L. Eller, Travis M. Dumont, Elad I. Levy and Adnan H. Siddiqui

Intravascular ultrasound (IVUS) generates high-resolution cross-sectional images and sagittal reconstructions of the vessel wall and lumen. As a result, this imaging modality can provide accurate measurements of the degree of vessel stenosis, allow the detection of intraluminal thrombus, and analyze the plaque composition. The IVUS modality is widely used in interventional cardiology, and its use in neurointerventions has gradually increased. With case examples, the authors illustrate the utility of IVUS as an adjunct to conventional angiography for a wide range of intracranial and extracranial neurointerventions.

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Ashish Sonig, Hussain Shallwani, Bennett R. Levy, Hakeem J. Shakir and Adnan H. Siddiqui

OBJECTIVE

Publication has become a major criterion of success in the competitive academic environment of neurosurgery. This is the first study that has used departmental h index–and e index–based matrices to assess the academic output of neuroendovascular, neurointerventional, and interventional radiology fellowship programs across the continental US.

METHODS

Fellowship program listings were identified from academic and organization websites. Details for 37 programs were available. Bibliometric data for these programs were gathered from the Thomson Reuters Web of Science database. Citations for each publication from the fellowship's parent department were screened, and the h and e indices were calculated from non–open-surgical, central nervous system vascular publications. Variables including “high-productivity” centers, fellowship–comprehensive stroke center affiliation, fellowship accreditation status, neuroendovascular h index, e index (h index supplement), h10 index (publications during the last 10 years), and departmental faculty-based h indices were created and analyzed.

RESULTS

A positive correlation was seen between the neuroendovascular fellowship h index and corresponding h10 index (R = 0.885; p < 0.0001). The mean, median, and highest faculty-based h indices exhibited positive correlations with the neuroendovascular fellowship h index (R = 0.662, p < 0.0001; R = 0.617, p < 0.0001; and R = 0.649, p < 0.0001, respectively). There was no significant difference (p = 0.824) in the median values for the fellowship h index based on comprehensive stroke center affiliation (30 of 37 programs had such affiliations) or accreditation (18 of 37 programs had accreditation) (p = 0.223). Based on the quartile analysis of the fellowship h index, 10 of 37 departments had an neuroendovascular h index of ≥ 54 (“high-productivity” centers); these centers had significantly more faculty (p = 0.013) and a significantly higher mean faculty h index (p = 0.0001).

CONCLUSIONS

The departmental h index and analysis of its publication topics can be used to calculate the h index of an associated subspecialty. The analysis was focused on the neuroendovascular specialty, and this methodology can be extended to other neurosurgical subspecialties. Individual faculty research interest is directly reflected in the research productivity of a department. High-productivity centers had significantly more faculty with significantly higher individual h indices. The current systems for neuroendovascular fellowship program accreditation do not have a meaningful impact on academic productivity.

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Aneela Darbar, Richard T. Stevens, Adnan H. Siddiqui, James S. McCasland and Charles J. Hodge

Object

The brain shows remarkable capacity for plasticity in response to injury. To maximize the benefits of current neurological treatment and to minimize the impact of injury, the authors examined the ability of commonly administered drugs, dextroamphetamine (D-amphetamine) and phenytoin, to positively or negatively affect the functional recovery of the cerebral cortex following excitotoxic injury.

Methods

Previous work from the same laboratory has demonstrated reorganization of whisker functional responses (WFRs) in the rat barrel cortex after excitotoxic lesions were created with kainic acid (KA). In the present study, WFRs were mapped using intrinsic optical signal imaging before and 9 days after creation of the KA lesions. During the post-lesion survival period, animals were either treated with intraperitoneal D-amphetamine, phenytoin, or saline or received no treatment. Following the survival period, WFRs were again measured and compared with prelesion data.

Results

The findings suggest that KA lesions cause increases in WFR areas when compared with controls. Treatment with D-amphetamine further increased the WFR area (p < 0.05) while phenytoin-treated rats showed decreases in WFR areas. There was also a statistically significant difference (p < 0.05) between the D-amphetamine and phenytoin groups.

Conclusions

These results show that 2 commonly used drugs, D-amphetamine and phenytoin, have opposite effects in the functional recovery/plasticity of injured cerebral cortex. The authors' findings emphasize the complex nature of the cortical response to injury and have implications for understanding the biology of the effects of different medications on eventual functional brain recovery.

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Peter T. Kan, Kenneth V. Snyder, Parham Yashar, Adnan H. Siddiqui, L. Nelson Hopkins and Elad I. Levy

Computed tomography perfusion scanning generates physiological flow parameters of the brain parenchyma, allowing differentiation of ischemic penumbra and core infarct. Perfusion maps, along with the National Institutes of Health Stroke Scale score, are used as the bases for endovascular stroke intervention at the authors' institute, regardless of the time interval from stroke onset. With case examples, the authors illustrate their perfusion-based imaging guidelines in patient selection for endovascular treatment in the setting of acute stroke.

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Sharon Webb, Parham Yashar, Peter Kan, Adnan H. Siddiqui, L. Nelson Hopkins and Elad I. Levy

Object

The treatment of acute intracranial vertebrobasilar artery occlusion (VBO) has been described but often with poor results. The authors of this study set out to evaluate their institution's outcomes following multimodal treatment of VBO.

Methods

They retrospectively reviewed their endovascular database for all patients treated for acute intracranial VBO between December 2004 and June 2010. Twenty-four patients were identified. Two patients were excluded from evaluation—one because of incomplete medical records and one because the etiology was basilar stenosis and not stroke. Occlusion location, hypercoagulable causes, time to endovascular treatment, time to revascularization, comorbidities, devices used, procedural anticoagulation, and outcomes were analyzed.

Results

Among the 22 eligible study patients, the mean National Institutes of Health Stroke Scale (NIHSS) score at presentation was 15.3. The mean time from presentation to initiation of the endovascular procedure was 4.77 hours. The mean time for recanalization from the start of angiography was 1.63 hours. In 16 patients (73%), revascularization was successful (Thrombolysis in Myocardial Infarction [TIMI] score of 2 or 3). Thirteen (59%) of the 22 patients were discharged to home or a rehabilitation facility. One patient was transferred to a chronic care facility. The overall survival rate was 64%. The average NIHSS score for the 14 surviving patients at discharge was 3.9. At the follow-up (average 14.5 months, range 1–58 months), 10 patients (71%) had achieved good outcomes (modified Rankin Scale [mRS] score ≤ 2) and 4 (29%) had poor outcomes (mRS Score 3–6).

Conclusions

Published case series have historically shown poor outcomes and high mortality rates in association with the treatment of acute VBO, prompting surgeons to be less aggressive in the treatment of this disease than they might be otherwise. Data in this series show that the revascularization of posterior circulation occlusions is feasible and that good outcomes and lower mortality rates with newer endovascular technologies are possible, and thus more prompt and aggressive treatment of this disease may be warranted.

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Stanley H. Kim, Adnan I. Qureshi, Elad I. Levy, Ricardo A. Hanel, Amir M. Siddiqui and L. Nelson Hopkins

✓ The authors report a case of emergency carotid artery (CA) stent placement for a symptomatic acute CA occlusion following carotid endarterectomy (CEA). This 43-year-old man underwent a right-sided CEA for an asymptomatic 80% CA stenosis detected using duplex ultrasound testing. The patient experienced hypotension and possibly a myocardial infarction intraoperatively and a left hemiplegia immediately postoperatively. He was referred to the authors' institution for consideration of emergency coronary intervention and evaluation of stroke. A computerized tomography scan of the head demonstrated subtle early ischemic changes in the right posterior parietal region. Cerebral angiography revealed occlusion of the right common CA (CCA) at the CA bifurcation. Two coronary stents (Magic Wall; Boston Scientific Scimed, Maple Grove, MN) were placed in tandem in the right CCA and internal CA (ICA), overlapping at the proximal cervical ICA. Complete recanalization of the CA was achieved, and the patient made a clinically significant recovery. Diagnostic angiography can provide important information about CA and intracranial circulation that will aid in the evaluation of postoperative stroke after CEA. Stent placement should be considered as an alternative method of treatment for acute CA occlusion or dissection following CEA.