J Mocco

Local saline infusion into ischemic territory induces regional brain cooling and neuroprotection in rats with transient middle cerebral artery occlusion.

OBJECTIVEThe neuroprotective effect of hypothermia has long been recognized. Use of hypothermia for stroke therapy, which is currently being induced by whole-body surface cooling, has been limited primarily because of management problems and severe side effects (e.g., pneumonia). The goal of this study was to determine whether local infusion of saline into ischemic territory could induce regional brain cooling and neuroprotection. METHODSA novel procedure was used to block the middle cerebral artery of rats for 3 hours with a hollow filament and locally infuse the middle cerebral artery-supplied territory with 6 ml cold saline (20°C) for 10 minutes before reperfusion. RESULTSThe cold saline infusion rapidly and significantly reduced temperature in cerebral cortex from 37.2 ± 0.1 to 33.4 ± 0.4°C and in striatum from 37.5 ± 0.2 to 33.9 ± 0.4°C. The significant hypothermia remained for up to 60 minutes after reperfusion. Significant (P < 0.01) reductions in infarct volume (approximately 90%) were evident after 48 hours of reperfusion. In ischemic rats that received the same amount of cold saline systemically through a femoral artery, a mild hypothermia was induced only in the cerebral cortex (35.3 ± 0.2°C) and returned to normal within 5 minutes. No significant reductions in infarct volume were observed in this group or in the ischemic group with local warm saline infusion or without infusion. Furthermore, brain-cooling infusion significantly (P < 0.01) improved motor behavior in ischemic rats after 14 days of reperfusion. This improvement continued for up to 28 days after reperfusion. CONCLUSIONLocal prereperfusion infusion effectively induced hypothermia and ameliorated brain injury from stroke. Clinically, this procedure could be used in acute stroke treatment, possibly in combination with intra-arterial thrombolysis or mechanical disruption of clot by means of a microcatheter.

Feasibility and Safety of Pipeline Embolization Device in Patients With Ruptured Carotid Blister Aneurysms

BACKGROUND Treatment of internal carotid ruptured blister aneurysms (IC-RBA) presents many challenges to neurosurgeons because of the high propensity for rebleeding during intervention. The role of a Pipeline Embolization Device (PED) in the treatment of this challenging aneurysm subtype remains undefined despite theoretical advantages. OBJECTIVE To present a series of 11 patients treated with a PED and to discuss the management and results of this novel application of flow diverters. METHODS Medical records of patients who presented with IC-RBA from May 2011 to March 2013 were retrospectively reviewed at 6 institutions in the United States. All relevant data were independently compiled. RESULTS A total of 12 IC-RBAs in 11 patients were treated during the study period. Nine (75%) were treated with a single PED; 1 was treated with 2 PEDs; 1 was treated with coils and 1 PED; and 1 was treated with coils and 2 PEDs. Three (27%) had major perioperative complications: middle cerebral artery territory infarction, vision loss, and death. Seven patients demonstrated complete obliteration of the aneurysm in postoperative imaging. Early clinical outcomes were favorable (modified Rankin Scale score, 0-2) in all 10 survivors. CONCLUSION This study demonstrates the feasibility and safety of using the PED to treat IC-RBA with fair initial results. The proper introduction and management of antiplatelet regimen are key for successful results. Bleeding complications related to dual antiplatelet therapy were similar to those in previous studies of stent-assisted coiling for the same population. Larger cohort analysis is needed to define the precise role of flow diverters in the treatment of IC-RBA.

Multidisciplinary consensus on assessment of unruptured intracranial aneurysms: proposal of an international research group.

Background and Purpose— To address the increasing need to counsel patients about treatment indications for unruptured intracranial aneurysms (UIA), we endeavored to develop a consensus on assessment of UIAs among a group of specialists from diverse fields involved in research and treatment of UIAs. Methods— After composition of the research group, a Delphi consensus was initiated to identify and rate all features, which may be relevant to assess UIAs and their treatment by using ranking scales and analysis of inter-rater agreement (IRA) for each factor. IRA was categorized as very high, high, moderate, or low. Results— Ultimately, 39 specialists from 4 specialties agreed (high or very high IRAs) on the following key factors for or against UIA treatment decisions: (1) patient age, life expectancy, and comorbid diseases; (2) previous subarachnoid hemorrhage from a different aneurysm, family history for UIA or subarachnoid hemorrhage, nicotine use; (3) UIA size, location, and lobulation; (4) UIA growth or de novo formation on serial imaging; (5) clinical symptoms (cranial nerve deficit, mass effect, and thromboembolic events from UIAs); and (6) risk factors for UIA treatment (patient age and life expectancy, UIA size, and estimated risk of treatment). However, IRAs for features rated with low relevance were also generally low, which underlined the existing controversy about the natural history of UIAs. Conclusions— Our results highlight that neurovascular specialists currently consider many features as important when evaluating UIAs but also highlight that the appreciation of natural history of UIAs remains uncertain, even within a group of highly informed individuals.

Astrocytoma with pilomyxoid features presenting in an adult

Pilomyxoid histology is presently considered to occur in pediatric brain tumors. We report an astrocytoma with pilomyxoid features presenting in an adult and discuss its relationship to both the established childhood pilomyxoid astrocytoma (PMA) and recently reported tanycytoma. A 28‐year‐old man with medically intractable seizures presented for surgical evaluation. MRI revealed a discrete lesion in the right amygdala/uncus region. The patient elected for craniotomy with stereotactic temporal lobe resection and excision of the lesion. Postoperatively, the patient has done well. At 30‐month follow up, he is seizure free and without evidence of tumor recurrence. We report an astrocytoma with pilomyxoid features presenting in an adult, illustrating that while this histological pattern is most commonly seen in children, it may also affect older individuals. Recognition of this enigmatic pattern in adult gliomas expands the currently accepted epidemiology for this lesion.

A meta-analysis of prospective randomized controlled trials evaluating endovascular therapies for acute ischemic stroke

Introduction A recent randomized controlled trial (RCT), the Multicenter Randomized CLinical trial of Endovascular treatment for Acute ischemic stroke in the Netherlands (MR CLEAN), demonstrated better outcomes with endovascular treatment compared with medical therapy for acute ischemic stroke (AIS). However, previous trials have provided mixed results regarding the efficacy of endovascular treatment for AIS. A meta-analysis of all available trial data was performed to summarize the available evidence. Methods A literature search was performed to identify all prospective RCTs comparing endovascular therapies with medical management for AIS. Two datasets were created: (1) all patients randomized after confirmation of large vessel occlusion (LVO) (consistent with the contemporary standard of practice at the majority of centers); and (2) all patients with outcome data who underwent randomization regardless of qualifying vascular imaging. The pre-specified primary outcome measure was modified Rankin Scale score of 0–2 at 90 days. A fixed-effect model was used to determine significance. Results Five prospective RCTs comparing endovascular therapies with medical management were included in dataset 1 (1183 patients) and six were included in dataset 2 (1903 total patients). Endovascular therapies were associated with significantly improved outcomes compared with medical management (OR 1.67, 95% CI 1.29 to 1.16, p=0.0001) for patients with LVO (dataset 1). This benefit persisted when patients from all six RCTs were included, even in the absence of confirmation of LVO (OR 1.27, 95% CI 1.05 to 1.54, p=0.019; dataset 2). Conclusions A meta-analysis of prospective RCTs comparing endovascular therapies with medical management demonstrates superior outcomes in patients randomized to endovascular therapy.

Surgical checklists: A detailed review of their emergence, development, and relevance to neurosurgical practice.

In the fall of 1999, the Institute of Medicine released “To Err is Human: Building a Safer Health System,” a sobering report on the safety of the American healthcare industry. This work and others like it have ushered in an era where the science of quality assurance has quickly become an integral facet of the practice of medicine. One critical component of this new era is the development, application, and refinement of checklists. In a few short years, the checklist has evolved from being perceived as an assault on the practitioner’ integrity to being welcomed as an important tool in reducing complications and preventing medical errors. In an effort to further expand the neurosurgical communitys acceptance of surgical checklists, we review the rationale behind checklists, discuss the history of medical and surgical checklists, and remark upon the future of checklists within our field.

Endovascular treatment of acute ischemic stroke: the end or just the beginning?

Various endovascular intraarterial approaches are available for treating patients with acute ischemic stroke who present with severe neurological deficits. Three recent randomized trials-Interventional Management of Stroke (IMS) III, Mechanical Retrieval and Recanalization of Stroke Clots Using Embolectomy (MR RESCUE), and Synthesis Expansion: A Randomized Controlled Trial on Intra-Arterial Versus Intravenous Thrombolysis in Acute Ischemic Stroke (SYNTHESIS Expansion)-evaluated the efficacy of endovascular treatment of acute ischemic stroke and, after failing to demonstrate any significant clinical benefit of endovascular therapies, raised concerns and questions in the medical community regarding the future of endovascular treatment for acute ischemic stroke. In this paper, the authors review the evolution of endovascular treatment strategies for the treatment of acute stroke and provide their interpretation of findings and potential limitations of the three recently published randomized trials. The authors discuss the advantage of stent-retriever technology over earlier endovascular approaches and review the current status and future directions of endovascular acute stroke studies based on lessons learned from previous trials.

Inflammation, Cerebral Vasospasm, and Evolving Theories of Delayed Cerebral Ischemia

Cerebral vasospasm (CVS) is a potentially lethal complication of aneurysmal subarachnoid hemorrhage (aSAH). Recently, the symptomatic presentation of CVS has been termed delayed cerebral ischemia (DCI), occurring as early as 3-4 days after the sentinel bleed. For the past 5-6 decades, scientific research has promulgated the theory that cerebral vasospasm plays a primary role in the pathology of DCI and subsequently delayed ischemic neurological decline (DIND). Approximately 70% of patients develop CVS after aSAH with 50% long-term morbidity rates. The exact etiology of CVS is unknown; however, a well-described theory involves an antecedent inflammatory cascade with alterations of intracellular calcium dynamics and nitric oxide fluxes, though the intricacies of this inflammatory theory are currently unknown. Consequently, there have been few advances in the clinical treatment of this patient cohort, and morbidity remains high. Identification of intermediaries in the inflammatory cascade can provide insight into newer clinical interventions in the prevention and management of cerebral vasospasm and will hopefully prevent neurological decline. In this review, we discuss current theories implicating the inflammatory cascade in the development of CVS and potential treatment targets.

Doppler ultrasonography screening of poor-grade subarachnoid hemorrhage patients increases the diagnosis of deep venous thrombosis

Abstract Background: Prophylactic anticoagulation greatly decreases the prevalence of deep venous thrombosis (DVT) in neurosurgical patients. Using Doppler ultrasonography (USG), recent studies demonstrate a 1% DVT detection rate following microsurgery or endovascular treatment for aneurysmal subarachnoid hemorrhage (aSAH). We hypothesize that reported statistics underestimate the DVT detection rate in this high risk cohort by accounting for only symptomatic thromboses. This study utilizes Doppler USG to examine the prevalence of DVT in a large population of aSAH patients and attempts to identify a high-risk subgroup within this cohort. Methods: We retrospectively examined 178 aSAH patients who underwent screening lower extremity Dopplers (LEDs) and 57 who did not undergo screening LEDs. All received pharmacologic and mechanical DVT prophylaxis. We analysed DVT prevalence within these two groups and compared rates to the literature. We then segregated patients according to Hunt–Hess grade and determined DVT prevalence within subgroups. Results: Patients who underwent LED screening demonstrated a 3.4% (6/178) DVT rate, compared to 0% (0/57) in the unscreened cohort. Our screening protocol yielded a thrombosis rate almost triple that reported in the literature (3.4% versus 1.2%). A significantly greater (p<0.05) percentage of screened Hunt–Hess III–V patients (6.5%, 6/93) had positive LEDs compared to Hunt–Hess I–II patients (0%, 0/85). Conclusion: These data suggest that while pharmacologic prophylaxis lowers the prevalence of symptomatic DVTs in aSAH patients, the number of asymptomatic DVTs remains significant, particularly in patients with formidable neurological deficits. While a formal cost-effective analysis is warranted, our data suggest that screening high-risk patients may increase the diagnosis of asymptomatic DVTs and potentially prevent serious medical complications.

Challenges of acute endovascular stroke trials.

Intravenous thrombolytic therapy with tissue-type plasminogen activator (tPA) has been approved for acute ischemic stroke since 1996. However, its tight time window means that many centers only treat a minority of patients. Effectiveness is limited by the low recanalization rates of large intracranial occlusions (4% distal internal carotid and basilar artery and 32%–37% M1 middle cerebral artery),1,2 which has high disability and mortality.3 Clinical outcome at 3 months is strongly associated with the timeliness and extent of reperfusion.4,5 These findings call for therapies beyond intravenous tPA to improve clinical outcomes in such patients. There is an unmet need to develop efficient therapies for acute stroke caused by proximal intracranial occlusion. Three recent endovascular randomized controlled trials (RCTs) were negative.6–8 These trials have been criticized for the use of older first-generation devices, slow recruitment, delayed times to reperfusion, and nonuniform requirement for demonstration of large-vessel occlusion for enrollment. Second-generation devices (Solitaire, Trevo), now referred to as stentrievers, in 2 RCTs have shown improved outcomes over the first-generation Merci device.9,10 Despite the absence of phase III randomized controlled trials showing their superiority, there has been a 6-fold increase in the endovascular procedures in the United States between 2004 and 2009 (0.1%–0.6%) when compared with a tripling in usage of intravenous tPA (1.2%–3.4%).11 This increase likely represents changes in the systems of developing treatment pathways for acute stroke victims. It is clear that further clinical trials are needed to provide definitive evidence that endovascular therapy is an effective adjunct to intravenous tPA. Several new trials have been started. Although there is hope that this generation of trials will show the superiority of endovascular treatment, it is important to recognize the challenges that these trials face. In addition, given the …