Critical Appraisal of Randomized Controlled Trials on Unruptured Brain Arteriovenous Malformations

OBJECTIVE

Brain arteriovenous malformations management remains controversial despite the numerous, available treatment options. Randomized controlled trials (RCTs) theoretically provide the strongest evidence for the assessment of any therapeutic intervention. However, poorly designed RCTs may be associated with biases, inaccuracies, and misleading conclusions. The purpose of our study is to assess reporting transparency and methodological quality of the existing RCTs.

METHODS

A search was performed in the PubMed, Scopus, Embase, clinicaltrials.gov, and Cochrane databases. The search was limited to English literature. We included all published RCTs reporting on the management of unruptured brain arteriovenous malformations. The eligible studies were evaluated by 5 blinded raters with the CONsolidated Standards of Reporting Trials 2010 statement and the risk-of-bias 2 tool. The inter-rater agreement was assessed with the Fleiss' Kappa.

RESULTS

A randomized trial of unruptured brain arteriovenous malformations (ARUBA) and treatment of brain arteriovenous malformations (TOBAS) trials were evaluated. ARUBA achieved high CONsolidated standards of reporting trials compliance, while TOBAS showed a moderate one. In ARUBA the introduction, discussion, and other information sections reached the highest compliance rate (80%-86%). The lowest rates were recorded in the results and the methods (62% and 73%, respectively). The inter-rater agreement was moderate to substantial (54.1% to 78.4%). All the examined studies demonstrated a high risk of bias, mainly related to ill-defined intended interventions, missing outcome data, and selection of the reported results.

CONCLUSIONS

Our study confirmed the high risk of bias mainly attributed to several protocol violations, deviations, minimal external validity and selection, attrition, and allocation biases of the ARUBA trial. Analysis of the TOBAS trial revealed a moderate overall reporting clarity and a high risk of bias.

A simple and cost-effective model for ventricular catheter placement training: technical note

OBJECTIVE

External ventricular drain (EVD) placement is one of first cranial procedures neurosurgery residents are expected to perform independently. While proper training improves patient outcomes, there are few options for practicing EVD placement prior to placing the EVD in patients in a clinical setting. Proposed solutions to this include using cadaveric models and virtual simulations, but barriers exist with these as well in regard to authenticity. EVD simulators using virtual reality technologies are a promising new technique for training, but the cost of these devices poses a barrier to general/widespread accessibility among smaller programs or underserved hospitals. The authors desribe a novel, yet simple, and cost-effective technique (less than $5 per mold) for developing a brain model constructed of homemade ballistics gelatin that can be used for teaching and practicing the placement of EVD.

METHODS

A brain model is made with ballistics gelatin using an anatomically correct skull model as a mold. A 3D-printed ventricular system model is used to create a mold of an anatomically correct ventricular system in the brain model. A group of medical students (n = 10) were given a basic presentation about EVD placement, including standard landmarks and placement techniques, and were also shown a demonstration of EVD placement on the brain model. They were then allowed to perform an EVD placement using the brain model. The students were surveyed on their experience with using the brain model, including usability and practicality of the model. Accuracy of EVD placement by each student was also assessed, with adequate position of catheter tip being in the ipsilateral frontal horn.

RESULTS

The final product is fairly inexpensive and easy to make. It is soft enough to pass a catheter through, but it is also firm enough to maintain its shape, including a cavity representing the lateral ventricles. The dense gelatin holds the catheter in its final resting position, while the two halves are separated and inspected. All participants in the test group of medical students reported that the brain model was easy to use, helped them understand the steps and technique of EVD placement, and provided good feedback on the ideal position of ventricular catheters. All of the participants in the group had adequate positioning of their ventricular catheters after one attempt.

CONCLUSIONS

The presented brain model is easy to replicate, inexpensive, anatomically accurate, and provides a medium for neurosurgeons to teach and practice ventricular catheter placement in a risk-free environment.

Arteriovenous Malformations: Congenital or Acquired Lesions?

OBJECTIVE

Arteriovenous malformations (AVMs) were believed to be congenital. However, an increasing number of de novo AVM cases have questioned this doctrine.

METHODS

A consensus meeting of international experts attempted to establish a consensus on the nature of these relatively rare but challenging vascular lesions. In addition, an extensive search of the subject was performed using the PubMed medical database.

RESULTS

All participants agreed that genetic factors may play a role in the pathogenesis of AVMs. All but 1 participant believed that an underlying genetic predisposition may be detected later on in a patient's life, whereas genetic variations may contribute to sporadic AVM formation. The presence of genetic variations alone may not be enough for an AVM formation. A second hit is probably required. This consensus opinion is also supported by our literature search.

CONCLUSIONS

We discuss the literature on the genetics of AVMs and compare it with the consensus meeting outcomes. The congenital or noncongenital character of intracranial AVMs has an impact on the understanding their biological behavior, as well as their efficient short-term and long-term management.

Sellar/Suprasellar Ganglioglioma: Clinical Image

BACKGROUND

This report presents a rare presentation of a ganglioglioma in the sellar/suprasellar region. On the basis of the patient's presentation and imaging characteristics, the initial diagnosis was craniopharyngioma. While gangliogliomas are already rare brain tumors that are usually found in the frontal and temporal lobes of young patients, the presentation of this tumor in the sellar region is exceedingly rare.

CASE DESCRIPTION

A 25-year-old male presented to the emergency department with headache, agitation, and combativeness. A head computed tomography scan showed a sellar/suprasellar mass with mixed solid and cystic components and peripheral calcifications. The mass compressed the third ventricle and cerebral aqueduct, resulting in obstructive hydrocephalus. The patient was intubated for decline in mental status and combativeness. A ventricular drain was placed emergently. A pituitary function panel did not show endocrine dysfunction. Magnetic resonance imaging showed a 3.6 cm × 4.2 cm solid mass in the sellar/suprasellar region with a cystic component. The mass displaced the adenohypophysis and extended into the prepontine and interpedicular cisterns. The clinical presentation and radiologic characteristics led to an initial diagnosis of craniopharyngioma. The patient underwent a right pterional craniotomy and transsylvian approach for resection of mass without complication, although a subtotal resection was achieved due to adherence of the tumor to optic nerves and carotid arteries. The resected specimen was diagnosed as ganglioglioma.

CONCLUSIONS

This case is a reminder of how much the field of neurosurgery relies on imaging modalities but also emphasizes the importance of histopathology in the field of brain tumors.

A Retrospective Cohort Analysis of Hemorrhagic Arteriovenous Malformations Treated with Combined Endovascular Embolization and Gamma Knife Stereotactic Radiosurgery

BACKGROUND

The management of brain arteriovenous malformations (AVMs) remains a controversial topic. Given the relatively low incidence, high heterogeneity, and high morbidity and mortality of these lesions, consensus on treatment strategies is an issue of concern to organized neurosurgery. The present retrospective analysis examined and quantified the outcomes of patients with an initial presentation of intracranial hemorrhage from a Spetzler-Martin grade III or IV AVM, later ruled out as surgical candidates.

METHODS

A total of 16 patients (5 females; 11 males) had presented with symptomatic hemorrhage confirmed by non-contrast-enhanced computed tomography and were deemed to not be surgical candidates owing to AVM location and/or architecture. The patients underwent combined endovascular embolization and gamma knife stereotactic radiosurgery (SRS). The modified Rankin scale was used to measure the clinical outcomes, comparing the scores at presentation, gamma knife treatment, and the last known follow-up examination. A radiographic evaluation was used to determine the level of AVM nidus involution after the procedure.

RESULTS

The present study identified 16 patients with ruptured high-grade AVMs of high surgical risk. All the patients had undergone immediate embolization with delayed SRS for treatment of the hemorrhage and nidus of the AVM. A statistically significant proportion of patients showed marked improvement in the modified Rankin scale scores. No subsequent repeat hemorrhage or any associated complications after embolization occurred in any patient.

CONCLUSION

These findings warrant consideration of endovascular embolization with adjuvant SRS as a powerful treatment option for cases with high surgical morbidity due to AVM characteristics.

Remote ischemic post-conditioning promotes hematoma resolution via AMPK-dependent immune regulation

Intracerebral hemorrhage is a devastating neurological injury that produces poor patient outcomes. In this report, Vaibhav et al. demonstrate that remote ischemic post-conditioning noninvasively accelerates hematoma resolution by enhancing AMPK-dependent alternative macrophage activation.

Spontaneous intracerebral hemorrhage (ICH) produces the highest acute mortality and worst outcomes of all stroke subtypes. Hematoma volume is an independent determinant of ICH patient outcomes, making clot resolution a primary goal of clinical management. Herein, remote-limb ischemic post-conditioning (RIC), the repetitive inflation–deflation of a blood pressure cuff on a limb, accelerated hematoma resolution and improved neurological outcomes after ICH in mice. Parabiosis studies revealed RIC accelerated clot resolution via a humoral-mediated mechanism. Whereas RIC increased anti-inflammatory macrophage activation, myeloid cell depletion eliminated the beneficial effects of RIC after ICH. Myeloid-specific inactivation of the metabolic regulator, AMPKα1, attenuated RIC-induced anti-inflammatory macrophage polarization and delayed hematoma resolution, providing a molecular link between RIC and immune activation. Finally, chimera studies implicated myeloid CD36 expression in RIC-mediated neurological recovery after ICH. Thus, RIC, a clinically well-tolerated therapy, noninvasively modulates innate immune responses to improve ICH outcomes. Moreover, immunometabolic changes may provide pharmacodynamic blood biomarkers to clinically monitor the therapeutic efficacy of RIC.

Cephalad Migration of Intradural Bullet from Thoracic Spine to Cervical Spine

BACKGROUND

There are few reported instances of intraspinal migration of a bullet fragment. The majority of these migrations occur caudally, typically below the level of T10. Even fewer cases demonstrate cephalad migration from the sacral spine to the lumbar spine. We report here for the first time a case of a cephalad migration intradurally from the thoracic spine to cervical spine.

CASE DESCRIPTION

A 31-year old man presented to the emergency department with a suspected spinal cord injury following a GSW sustained to the left shoulder. A penetrating gunshot injury to the thoracic spine at the level of T2 was observed, and CT angiography revealed a cephalad migration of the bullet fragment to the level of C6. The patient had marked weakness of the bilateral upper extremities, with paraplegia of the lower extremities. There was a sensory deficit beginning at a level 1 cm below the clavicle, as well as a decrease in rectal tone. We performed a laminectomy at C6 with dural incision and removal of the main bullet fragment. Following the surgery, significant improvement in strength and sensation in the bilateral upper extremities was noted, but paraplegia and sensory loss below the level of T2 persisted.

CONCLUSIONS

In this report, we review the previously reported cases in which intraspinal migration of bullets have occurred, and discuss the unique finding in this study of cephalad migration of a bullet within the dura. In addition, we detail considerations in the management of such injuries.

[125 I]IodoDPA-713 Binding to 18 kDa Translocator Protein (TSPO) in a Mouse Model of Intracerebral Hemorrhage: Implications for Neuroimaging

Intracerebral hemorrhage (ICH) is a fatal stroke subtype with significant public health impact. Although neuroinflammation is a leading cause of neurological deficits after ICH, no imaging tool is currently available to monitor brain inflammation in ICH patients. Given the role of TSPO in neuroinflammation, herein we investigate whether a second-generation TSPO ligand, [¹²⁵ I]IodoDPA-713 can be used to monitor the changes in TSPO expression in a preclinical model of intracerebral hemorrhage. Male CD1 mice were subjected to ICH/Sham. The brain sections, collected at different time points were incubated with [¹²⁵ I]IodoDPA-713 and the brain uptake of [¹²⁵ I]IodoDPA-713 was estimated using autoradiography. The specificity of [¹²⁵ I]IodoDPA-713 binding was confirmed by a competitive displacement study with an unlabeled TSPO ligand, PK11195. [¹²⁵ I]IodoDPA-713 binding was higher in the ipsilateral striatum with an enhanced binding observed in the peri-hematomal brain region after ICH, whereas the brain sections from sham as well as contralateral brain areas of ICH exhibited marginal binding of [¹²⁵ I]IodoDPA-713. PK11195 completely reversed the [¹²⁵ I] IodoDPA-713 binding to brain sections suggesting a specific TSPO-dependent binding of [¹²⁵ I]IodoDPA-713 after ICH. This was further confirmed with immunohistochemistry analysis of adjacent sections, which revealed a remarkable expression of TSPO in the areas of high [¹²⁵ I]IodoDPA-713 binding after ICH. The specific as well as enhanced binding of [¹²⁵ I]IodoDPA-713 to the ipsilateral brain areas after ICH as assessed by autoradiography analysis provides a strong rationale for testing the applicability of [¹²⁵ I]IodoDPA-713 for non-invasive neuroimaging in preclinical models of ICH.

Resveratrol Attenuates Neurodegeneration and Improves Neurological Outcomes after Intracerebral Hemorrhage in Mice

Intracerebral hemorrhage (ICH) is a devastating type of stroke with a substantial public health impact. Currently, there is no effective treatment for ICH. The purpose of the study was to evaluate whether the post-injury administration of Resveratrol confers neuroprotection in a pre-clinical model of ICH. To this end, ICH was induced in adult male CD1 mice by collagenase injection method. Resveratrol (10 mg/kg) or vehicle was administered at 30 min post-induction of ICH and the neurobehavioral outcome, neurodegeneration, cerebral edema, hematoma resolution and neuroinflammation were assessed. The Resveratrol treatment significantly attenuated acute neurological deficits, neurodegeneration and cerebral edema after ICH in comparison to vehicle treated controls. Further, Resveratrol treated mice exhibited improved hematoma resolution with a concomitant reduction in the expression of proinflammatory cytokine, IL-1β after ICH. Altogether, the data suggest the efficacy of post-injury administration of Resveratrol in improving acute neurological function after ICH.

Anterior Gray Matter Pituicytic Heterotopia with Monomorphic Anterior Pituitary Cells: A Variant of Nonsecretory Pituitary Adenoma Neuronal Choristoma? Report of a Rare Case and Review of the Literature

BACKGROUND

Mixed tumors of adenomatous and neuronal cells in the sellar region are an uncommon finding. The origins of these heterogeneous tumors are unknown, and management remains unsettled. We report a very rare case of anterior gray matter pituicytic heterotopia with monomorphic anterior pituitary cells that likely represents a variant of nonsecreting pituitary adenoma neuronal choristoma (PANCH) with no ganglion cells. We also review the current literature for the various clinical presentations of PANCH.

CASE DESCRIPTION

A 49-year-old female complaining of headache, blurred vision, and hair loss was found to have a nonsecretory sellar mass with compression of the optic chiasm on magnetic resonance imaging (MRI). The mass was excised via a transsphenoidal procedure. Histological analysis of tissue sections revealed heterotopic gray matter with reactive gliosis without ganglion cells or Herring bodies. Only 1 smear exhibited characteristics of a pituitary adenoma.

CONCLUSIONS

The overall findings were most consistent with a variant of PANCH. At a postoperative follow-up of 4.5 years, there was resolution of visual symptoms, and the residual sellar mass was stable on MRI. Neuronal choristoma is hypothesized to originate from embryonal pituitary or hypothalamus, or by differentiation from pituitary adenoma cells. Surgery is the cornerstone of management, and the clinical course appears to be similar to that of nonfunctioning pituitary adenoma in reported cases.

Post-Injury Administration of Tert-butylhydroquinone Attenuates Acute Neurological Injury After Intracerebral Hemorrhage in Mice

Intracerebral hemorrhage (ICH) is a severe form of stroke with substantial public health impact. Notably, there is no effective treatment for ICH. Given the role of transcription factor Nrf2 (NF-E2-related factor 2) in antioxidant signaling, herein, we tested the efficacy of tert-butylhydroquinone (TBHQ), a selective inducer of Nrf2 in a preclinical model of ICH. Male CD1 mice were subjected to experimental intracerebral hemorrhage and administered intraperitoneally with TBHQ. The administration of TBHQ enhanced the DNA-binding activity of Nrf2 in the brain and reduced oxidative brain damage in comparison to vehicle-treated ICH. In addition, TBHQ treatment reduced microglial activation with concomitant reduction in the release of proinflammatory cytokine interleukin-1β (IL-1 β). Furthermore, TBHQ treatment attenuated neurodegeneration and improved neurological outcomes after ICH. Altogether, the data demonstrate the efficacy of post-injury administration of TBHQ in attenuating acute neurological injury after ICH.

The Histone Deacetylase Inhibitor Suberoylanilide Hydroxamic Acid (SAHA) Confers Acute Neuroprotection After Intracerebral Hemorrhage in Mice

Spontaneous intracerebral hemorrhage (ICH) is a stroke subtype with no effective treatment. Though ICH is known to induce severe neurological damage, the molecular mechanisms of neurological injury after ICH remain largely unclear. Given the emerging role of epigenetic mechanisms in neurodegeneration, the present study evaluated whether suberoylanilide hydroxamic acid (SAHA: vorinostat), a clinically well-tolerated pan-histone deacetylase inhibitor (HDACi), would attenuate neurological injury and improve functional outcomes in a preclinical model of ICH. Mice were administered with SAHA or vehicle after an induction of ICH and acute neuronal death, glial activation, and neurological outcomes were assessed. SAHA-treated mice exhibited less neurodegeneration with concomitant improvement in neurological outcomes than vehicle-treated mice. Furthermore, SAHA downregulated glial activation and the expression of heme oxygenase-1, a stress-inducible enzyme that plays critical roles in neurological damage after ICH. Altogether, the data strongly suggest the role of epigenetic mechanisms in inducing neurological injury after ICH and raise the possible clinical utility of SAHA for therapeutic intervention after ICH.

Overexpression of Nrf2 attenuates Carmustine-induced cytotoxicity in U87MG human glioma cells

Background

Malignant glioma is one of the most devastating tumors in adults with poor patient prognosis. Notably, glioma often exhibits resistance to conventional chemotherapeutic approaches, complicating patient treatments. However, the molecular mediators involved in tumor chemoresistance remain poorly defined, creating a barrier to the successful management of glioma. In the present study, we hypothesized that the antioxidant transcription factor, Nrf2 (nuclear factor erythroid-derived 2 like 2), attenuates glioma cytotoxicity to Carmustine (BCNU), a widely used chemotherapeutic agent known to modulate cellular oxidative balance.

Methods

To test the hypothesis, we employed human malignant glioma cell line, U87MG and overexpression of Nrf2 in glioma cells was achieved using both pharmacological and genetic approaches.

Results

Notably, induction of Nrf2 was associated with increased expression of heme oxygenase-1 (HO-1), a stress inducible enzyme involved in anti-oxidant defense. In addition, over expression of Nrf2 in U87MG cells significantly attenuated the cytotoxicity of Carmustine as evidenced by both cellular viability assay and flow cytometry analysis. Consistent with this, antioxidants such as glutathione and N-acetyl cysteine significantly reduced Carmustine mediated glioma cytotoxicity.

Conclusions

Taken together, these data strongly implicate an unexplored role of Nrf2 in glioma resistance to Carmustine and raise the possible use of Nrf2 inhibitors as adjunct to Carmustine for the treatment of malignant glioma.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-015-1134-z) contains supplementary material, which is available to authorized users.

Neurosurgery at Medical College of Georgia, Georgia Regents University in Augusta (1956-2013)

: The neurosurgery service at the Medical College of Georgia, Georgia Regents University at Augusta has a rich history spanning almost 6 decades. Here, we review the development of neurological surgery as a specialty in Augusta and the history of the Department of Neurosurgery at Georgia Regents University. This article describes some of the early neurosurgeons in the city and those who have contributed to the field and helped to shape the department. Our functional and stereotactic program is emphasized. Our surgical epilepsy program dates back more than a half-century and remains a highly experienced program. We also describe our affiliation with the medical illustration graduate program, which was the first to be accredited and remains 1 of 4 such programs in the world. Finally, we list our alumni, former faculty, and current faculty, as well as the major accomplishments in our first decade as a full department.

Cerebral vascular malformations in hereditary hemorrhagic telangiectasia

Object

Hereditary hemorrhagic telangiectasia (HHT) is a hereditary disorder characterized by mucocutaneous telangiectasias, frequent nosebleeds, and visceral arteriovenous malformations (AVMs). Few reports have outlined the prevalence of the various cerebral vascular malformations found in patients with HHT. The authors set out to define the prevalence of cerebral vascular malformations in a population of HHT patients who underwent imaging with 3-T imaging (MRI/MR angiography [MRA]) of the brain.

Methods

A retrospective review of prospectively collected data was carried out using a database of 372 HHT patients who were seen and examined at the Georgia Regents University HHT Center and screened with 3-T MRI/MRA. Data were tabulated for numbers and types of vascular malformations in this population.

Results

Arteriovenous malformations were identified in 7.7%, developmental venous anomalies in 4.3%, and cerebral aneurysms in 2.4% of HHT patients. The HHT AVMs tended to be supratentorial, small, and cortical in this series, findings consistent with other recent studies in the literature. An arteriovenous fistula, cavernous malformation, and capillary telangiectasia were identified in 0.5%, 1%, and 1.9% of HHT patients, respectively.

Conclusions

Few studies have investigated the prevalence of the various vascular malformations found in HHT patients screened with 3-T MRI/MRA of the brain. Hereditary hemorrhagic telangiectasia AVMs are more likely to be multiple and have a tendency toward small size and cortical location. As such, they are often treated using a single-modality therapy.

Teaching neuroimages: microvascular decompression of the optic nerve

Vascular compression is a known cause of cranial nerve dysfunction in a variety of disease states including trigeminal neuralgia, hemifacial spasm, and hypoglossal neuralgia.(1,2.)

Bilateral transverse sinus stenosis causing intracranial hypertension

Idiopathic intracranial hypertension (IIH) has been associated with transverse sinus stenosis in a number of cases. Some authors advocate for stent placement when transverse sinus stenosis is responsible for pseudotumor symptoms. A 19-year-old man with IIH, bilateral transverse sinus stenosis was apparent on a CT venography, with reconstitution of the lateral sinus. MRI was then performed, and transverse sinus stenosis was confirmed. An impressive network of dilated collateral veins became apparent on VENBOLD sequences. Treatment options in this case include cerebrospinal fluid (CSF) shunting, optic nerve fenestrations and transverse sinus stenting. A ventriculoperitoneal shunt was placed in this patient, with prompt resolution of pseudotumor symptoms.

Expanded endoscopic endonasal approaches to skull base meningiomas

Anterior cranial base meningiomas have traditionally been addressed via frontal or frontolateral approaches. However, with the advances in endoscopic endonasal treatment of pituitary lesions, the transphenoidal approach is being expanded to address lesions of the petrous ridge, anterior clinoid, clivus, sella, parasellar region, tuberculum, planum, olfactory groove, and crista galli regions. The expanded endoscopic endonasal approach (EEEA) has the advantage of limiting brain retraction and resultant brain edema, as well as minimizing manipulation of neural structures. Herein, we describe the techniques of transclival, transphenoidal, transplanum, and transcribiform resections of anterior skull base meningiomas. Selected cases are presented.

TNF-alpha receptor antagonist, R-7050, improves neurological outcomes following intracerebral hemorrhage in mice

Intracerebral hemorrhage (ICH), the most common form of hemorrhagic stroke, exhibits the highest acute mortality and the worst long-term prognosis of all stroke subtypes. Unfortunately, treatment options for ICH are lacking due in part to a lack of feasible therapeutic targets. Inflammatory activation is associated with neurological deficits in pre-clinical ICH models and with patient deterioration after clinical ICH. In the present study, we tested the hypothesis that R-7050, a novel cell permeable triazoloquinoxaline inhibitor of the tumor necrosis factor receptor (TNFR) complex, attenuates neurovascular injury after ICH in mice. Up to 2h post-injury administration of R-7050 significantly reduced blood-brain barrier opening and attenuated edema development at 24h post-ICH. Neurological outcomes were also improved over the first 3 days after injury. In contrast, R-7050 did not reduce hematoma volume, suggesting the beneficial effects of TNFR inhibition were downstream of clot formation/resolution. These data suggest a potential clinical utility for TNFR antagonists as an adjunct therapy to reduce neurological injury and improve patient outcomes after ICH.

Open surgical management of a ruptured intracranial aneurysm in Klippel-Trenaunay-Weber (KTW) syndrome

A 24-year-old man with a history of Klippel-Trenaunay-Weber syndrome presented with severe headache and neck pain. Work-up revealed subarachnoid hemorrhage and evidence of multiple intracranial aneurysms. The patient was treated with open surgical clipping of his ruptured aneurysm and is currently doing well.

Astrocyte-specific expression of survivin after intracerebral hemorrhage in mice: a possible role in reactive gliosis?

Intracerebral hemorrhage (ICH), the most common form of hemorrhagic stroke, accounts for up to 15% of all strokes. Despite maximal surgical intervention and supportive care, ICH is associated with significant morbidity and mortality, in part due to a lack of viable treatment options. Astrogliosis, a key feature of secondary injury that is characterized by glial proliferation, is a poorly-defined process that may produce both beneficial and detrimental outcomes after brain injury. Using a pre-clinical murine model of collagenase-induced ICH, we demonstrate a delayed upregulation of survivin, a key molecule involved in tumor cell proliferation and survival, by 72 h post-ICH. Notably, this increase in survivin expression was prominent in GFAP-positive astrocytes, but absent in neurons. Survivin was not expressed at detectable levels in the striatum of sham-operated mice. The expression of survivin after ICH was temporally and spatially associated with the expression of proliferating cell nuclear antigen (PCNA), an established marker of cellular proliferation. Moreover, the survivin expression was co-localized in proliferating astrocytes as evidenced by triple-label immunohistochemistry. Finally, shRNA-mediated silencing of survivin expression attenuated PCNA expression and reduced cellular proliferation in human glial cells. Together, these data suggest a potentially novel role for survivin in functionally promoting astrocytic proliferation after ICH.

George W. Smith, M.D. (1916-1964)

Dr. George W. Smith is credited with developing the Smith-Robinson procedure, the automatic drill, the vessel-encircling aneurysm clip, and treatment of tic douloureux with stilbamidine. His contributions to neurosurgery were unfortunately truncated by his untimely death. This article highlights his career and his contributions.

Unusual case of subarachnoid haemorrhage in patient with Fabry's disease: case report and literature review

Fabry's disease is a rare, X linked recessive disease affecting 1 in 40 000 persons. The symptoms result from a lack of or a non-functioning enzyme α galactosidase, which leads to globotriaosylceramide accumulation in the walls of blood vessels. Mortality is generally from cardiac or renal complications and death from subarachnoid haemorrhage is distinctly rare. The authors report a man with Fabry's disease who died after subarachnoid haemorrhage from a progressively enlarging fusiform basilar aneurysm.

Rare giant traumatic cervical arteriovenous fistula in neurofibromatosis type 1 patient

Arteriovenous fistulas can rarely occur in patients with neurofibromatosis type 1. These lesions typically result from traumatic insult to the dysplastic parent artery. The damaged artery forms abnormal connections with nearby paraspinal and epidural venous structures. Surgical treatment of these lesions can be extremely challenging given the proximity to the spinal cord and the ability of the fistula to recruit vessels from adjacent vascular structures. A 29-year-old woman with neurofibromatosis type 1 and a motor vehicle collision 2 years earlier presented with gait difficulty, lower extremity spasticity and neck and arm pain. Her investigation revealed a giant cervical vertebral arteriovenous fistula. The fistula was successfully treated in multiple stages using all endovascular techniques including detachable coils, stents and glue embolisation. Reduction in flow and improvement in symptoms are reasonable goals in this specific rare subgroup of complex cervical arteriovenous fistulae.

Age-dependent lethality in novel transgenic mouse models of central nervous system arteriovenous malformations

BACKGROUND AND PURPOSE

The lack of an appropriate animal model has been a limitation in studying hemorrhage from arteriovenous malformations (AVMs) in the central nervous system.

METHODS

Novel mouse central nervous system AVM models were generated by conditionally deleting the activin receptor-like kinase (Alk1; Acvrl1) gene with the SM22-Cre transgene. All mice developed AVMs in their brain and/or spinal cord, and >80% of them showed a paralysis or lethality phenotype due to internal hemorrhages during the first 10 to 15 weeks of life. The mice that survived this early lethal period, however, showed significantly reduced lethality rates even though they carried multiple AVMs.

RESULTS

The age-dependent change in hemorrhage rates allowed us to identify molecular factors uniquely upregulated in the rupture-prone AVM lesions.

CONCLUSIONS

Upregulation of angiopoietin 2 and a few inflammatory genes were identified in the hemorrhage-prone lesions, which may be comparable with human pathology. These models will be an exceptional tool to study pathophysiology of AVM hemorrhage.

Dural-based metastatic carcinomas mimicking primary CNS neoplasia: report of 7 cases emphasizing the role of timely surgery and accurate pathologic evaluation

Clinical presentation with dural-based metastasis mimicking meningiomas is rare. We aimed to evaluate the role of frozen section in guiding surgery and histopathologic diagnosis in determining primary sites of dural-based metastatic carcinomas. Following the receipt of HAC approval, we retrospectively reviewed 7cases presenting with dural-based masses clinically suspected to be primary brain tumors (6 meningiomas and 1 superficial glioblastoma), but diagnosed to be metastatic carcinomas on subsequent resection. Pertinent clinical records and follow-up data were reviewed. Patient's age ranged from 59 to 80 years. Imaging showed extra-axial dural-based masses with contiguous but not primary brain involvement. On intra-operative frozen section (not performed in case 7), differential diagnoses included metastatic carcinoma in all cases, and surgery modified accordingly. Nesting, cribriform, and "picket-fence" like glands were among useful histologic diagnostic patterns. Immunoprofile supported histologic diagnosis in all cases. Subsequent clinical and radiologic evaluation confirmed coexistent sites of origin in all cases. The metastases were solitary in all cases; except multiple dural-based tumors in case 1, in which interestingly no systemic metastasis were identified. Dural-based metastatic carcinomas mimicking meningiomas may be solitary, of unknown primary, or without concomitant systemic spread on imaging. Frozen section evaluation is helpful in modifying surgery. Although high-grade, these are typically differentiated enough to allow accurate histopathologic diagnosis, and reasonable determination of primary tumor site, especially with a judicious panel of cytokeratins, transcription factors, hormone receptors and relatively organ-specific markers. Clinicians and pathologists need to be aware of the occurrence, spectrum, need for timely intervention, and accurate diagnosis of dural-based metastatic carcinomas.

Attenuation of hematoma size and neurological injury with curcumin following intracerebral hemorrhage in mice

OBJECT

Intracerebral hemorrhage (ICH) is associated with significant morbidity and mortality. Acute hematoma enlargement is an important predictor of neurological injury and poor clinical prognosis; but neurosurgical clot evacuation may not be feasible in all patients and treatment options remain largely supportive. Thus, novel therapeutic approaches to promote hematoma resolution are needed. In the present study, the authors investigated whether the curry spice curcumin limited neurovascular injury following ICH in mice.

METHODS

Intracerebral hemorrhage was induced in adult male CD-1 mice by intracerebral administration of collagenase or autologous blood. Clinically relevant doses of curcumin (75-300 mg/kg) were administered up to 6 hours after ICH, and hematoma volume, inflammatory gene expression, blood-brain barrier permeability, and brain edema were assessed over the first 72 hours. Neurological assessments were performed to correlate neurovascular protection with functional outcomes.

RESULTS

Curcumin increased hematoma resolution at 72 hours post-ICH. This effect was associated with a significant reduction in the expression of the proinflammatory mediators, tumor necrosis factor-α, interleukin-6, and interleukin-1β. Curcumin also reduced disruption of the blood-brain barrier and attenuated the formation of vasogenic edema following ICH. Consistent with the reduction in neuroinflammation and neurovascular injury, curcumin significantly improved neurological outcome scores after ICH.

CONCLUSIONS

Curcumin promoted hematoma resolution and limited neurological injury following ICH. These data may indicate clinical utility for curcumin as an adjunct therapy to reduce brain injury and improve patient outcome.

Astrocyte-derived glutathione attenuates hemin-induced apoptosis in cerebral microvascular cells

Intracerebral hemorrhage (ICH) induces neurovascular injury via poorly defined mechanisms. The aim of this study was to determine whether gliovascular communication may restrict hemorrhagic vascular injury. Hemin, a hemoglobin by-product, concentration- and time-dependently increased apoptotic cell death in mouse bEnd.3 cells and in primary human brain microvascular endothelial cells, at least in part, via a caspase-3 dependent pathway. Cell death was preceded by a NFκB-mediated increase in inflammatory gene expression, including upregulation of inducible nitric oxide synthase (iNOS) expression and activity. Functionally, inhibition of iNOS or the addition of a peroxynitrite decomposition catalyst reduced cell death. Interestingly, co-treatment with astrocyte-conditioned media (ACM) reversed hemin-induced NFκB activation, nitrotyrosine formation, and apoptotic cell death, at least in part, via the release of the endogenous antioxidant, reduced glutathione (GSH). Prior treatment of astrocytes with the GSH-depleting agent, DL-buthionine (S,R)-sulfoximine or direct addition of diethyl maleate, a thiol-depleting agent, to ACM reversed the observed protection. In contrast, neither exogenous GSH nor the GSH precursor, N-acetylcysteine, was protective in bEnd.3 cells. Together, these data support an important role for astrocyte-derived GSH in the maintenance of oxidative balance in the vasculature and suggest therapeutic targeting of the GSH system may reduce neurological injury following ICH.

Postoperative pain management with tramadol after craniotomy: evaluation and cost analysis

OBJECT

Patients undergoing craniotomies have traditionally received opiates with acetaminophen for the management of their postoperative pain. The use of narcotic pain medications can be costly, decrease rates of early postoperative ambulation, lengthen hospital stays, and alter a patient's neurological examination. The use of alternative pain medications such as tramadol may benefit patients by resolving many of these issues.

METHODS

The authors conducted a randomized, blinded prospective study to evaluate the efficacy of alternative pain management strategies for patients following craniotomies. Fifty patients were randomly assigned either to a control group who received narcotics and acetaminophen alone or an experimental group who received tramadol in addition to narcotic pain medications (25 patients assigned to each group).

RESULTS

The control group was noted to have statistically significant higher visual analog scale pain scores, an increased length of hospital stay, and increased narcotic use compared with the tramadol group. The narcotics and acetaminophen group also had increased hospitalization costs when compared with the tramadol group.

CONCLUSIONS

The use of scheduled atypical analgesics such as tramadol in addition to narcotics with acetaminophen for the management of postoperative pain after craniotomy may provide better pain control, decrease the side effects associated with narcotic pain medications, encourage earlier postoperative ambulation, and reduce total hospitalization costs.

Elucidating novel mechanisms of brain injury following subarachnoid hemorrhage: an emerging role for neuroproteomics

Subarachnoid hemorrhage (SAH) is a devastating neurological injury associated with significant patient morbidity and death. Since the first demonstration of cerebral vasospasm nearly 60 years ago, the preponderance of research has focused on strategies to limit arterial narrowing and delayed cerebral ischemia following SAH. However, recent clinical and preclinical data indicate a functional dissociation between cerebral vasospasm and neurological outcome, signaling the need for a paradigm shift in the study of brain injury following SAH. Early brain injury may contribute to poor outcome and early death following SAH. However, elucidation of the complex cellular mechanisms underlying early brain injury remains a major challenge. The advent of modern neuroproteomics has rapidly advanced scientific discovery by allowing proteome-wide screening in an objective, nonbiased manner, providing novel mechanisms of brain physiology and injury. In the context of neurosurgery, proteomic analysis of patient-derived CSF will permit the identification of biomarkers and/or novel drug targets that may not be intuitively linked with any particular disease. In the present report, the authors discuss the utility of neuroproteomics with a focus on the roles for this technology in understanding SAH. The authors also provide data from our laboratory that identifies high-mobility group box protein-1 as a potential biomarker of neurological outcome following SAH in humans.

Curcumin attenuates vascular inflammation and cerebral vasospasm after subarachnoid hemorrhage in mice

Cerebral vasospasm is a major cause of death and disability after subarachnoid hemorrhage (SAH); however, clinical therapies to limit the development of cerebral vasospasm are lacking. Although the causative factors underlying the development of cerebral vasospasm are poorly understood, oxidative stress contributes to disease progression. In the present study, curcumin (150 or 300 mg/kg) protected against the development of cerebral vasospasm and limited secondary cerebral infarction after SAH in mice. The protective effect of curcumin was associated with a significant attenuation of inflammatory gene expression and lipid peroxidation within the cerebral cortex and the middle cerebral artery. Despite the ability of curcumin to limit the development of cerebral vasospasm and secondary infarction, behavioral outcome was not improved, indicating a dissociation between cerebral vasospasm and neurologic outcome. Together, these data indicate a novel role for curcumin as a possible adjunct therapy after SAH, both to prevent the development of cerebral vasospasm and to reduce oxidative brain injury after secondary infarction.

Neurosarcoidosis with necrotising sarcoid granulomatosis mimicking meningiomatosis cerebri: case report and literature search

A 52-year-old woman presented with headaches, difficulty with word finding and left eye blindness. MRI showed enhancing frontal dural-based masses suggestive of meningiomatosis. Biopsy and debulking revealed necrotising granulomas, without discernible micro-organisms or neoplasia; a thorough clinical work-up was negative for infection and vasculitis. A CT scan showed mild bilateral hilar lymphadenopathy, a tiny pulmonary nodule and cirrhotic liver. Her subsequent alteration of mental status was attributed to hepatic encephalopathy based upon elevated aminotransferase and ammonia levels, biopsy evidence of hepatoportal sclerosis with rare granulomas and response to lactulose. A diagnosis of neurosarcoidosis of the necrotising sarcoid granulomatosis variant (NS-NSG) with atypical systemic involvement was made. This is the fifth case report of NS-NSG clinically mimicking a neoplasm and histologically mimicking a mycobacterial infection. NS-NSG can have an atypical clinical picture including intracranial masses; a thorough work-up to exclude infectious and other non-infectious aetiologies is a prerequisite to its diagnosis.

Hemin-induced necroptosis involves glutathione depletion in mouse astrocytes

Intracerebral hemorrhage (ICH) is a devastating neurological injury associated with significant mortality. Astrocytic inflammation may contribute to the pathogenesis of ICH, although the underlying cellular mechanisms remain unclear. In this study, the hemoglobin oxidation by-product, hemin, concentration dependently induced necroptotic cell death in cortical astrocytes within 5 h of treatment. Hemin-induced cell death was preceded by increased inflammatory gene expression (COX-2, IL-1beta, TNF-alpha, iNOS). Inhibition of the NF-kappaB transcription factor reversed inflammatory gene expression and attenuated cell death after hemin treatment, suggesting a possible role for inflammatory mediators in astrocytic injury. Superoxide production paralleled the increase in iNOS expression, and inhibition of either iNOS (aminoguanidine or iminopiperdine) or superoxide (apocynin) significantly reduced cell death. Similarly, reduced formation of peroxynitrite, the damaging product of nitric oxide and superoxide, significantly reduced hemin injury. Hemin-induced peroxidative injury was associated with a rapid depletion of intracellular glutathione (GSH), culminating in lipid peroxidation and cell death, effects that were reduced by cotreatment with exogenous GSH, N-acetyl-L-cysteine, or the glutathione peroxidase mimetic ebselen. Together, these studies suggest a novel role for GSH depletion in necroptotic astrocyte injury after a hemorrhagic injury and indicate that therapeutic targeting of GSH may exert a beneficial effect after ICH.

Postoperative pain management after craniotomy: evaluation and cost analysis

OBJECTIVE

Patients undergoing craniotomies have traditionally received opiates for the management of their postoperative pain. The use of narcotic pain medications can be costly, can decrease early walking, can lengthen hospital stay, and can alter a patient's neurological examination results. The use of alternative pain medications such as cyclooxygenase-2 (COX-2) inhibitors may benefit patients by resolving many of these issues. Compared with traditional nonsteroidal anti-inflammatory drugs, these anti-inflammatory medications may be used safely in neurosurgical patients because of their selective inhibition of the COX-2 enzyme, which avoids the platelet dysfunction caused by other nonsteroidal anti-inflammatory drugs.

METHODS

A randomized, single-blinded prospective study was used to evaluate the efficacy of alternative pain management strategies for patients who have undergone craniotomy. Twenty-seven patients were randomly assigned to a control group (n = 13) receiving narcotics alone or an experimental group (n = 14) receiving a COX-2 inhibitor in addition to narcotic pain medications.

RESULTS

The narcotics group was noted to have statistically significantly higher visual analog scale scores, increased length of stay, and increased narcotic use compared with the COX-2 group. The narcotics group also had increased hospitalization costs when compared with the COX-2 group.

CONCLUSION

The use of scheduled atypical analgesics, such as COX-2 inhibitors, in addition to narcotics for the management of postoperative pain after craniotomy may provide better pain control, may decrease side effects associated with narcotic pain medications, may encourage earlier walking, and may reduce total hospitalization costs.

Evolution of the treatment of cerebral vasospasm

Cerebral vasospasm following aneurysmal subarachnoid hemorrhage (SAH) is a disease process for which the lack of effective treatments has plagued neurosurgeons for decades. Historically, successful treatment after SAH in the acute setting was often followed by a rapid, uncontrollable deterioration in the subacute interval. Little was known regarding the nature and progression of this condition until the mid-1800s, when the disease was first described by Gull. Insight into the origin and natural history of cerebral vasospasm came slowly over the next 100 years, until the 1950s. Over the past five decades our understanding of cerebral vasospasm has expanded exponentially. This newly discovered information has been used by neurosurgeons worldwide for successful treatment of complications associated with vasospasm. Nevertheless, although great strides have been made toward elucidating the causes of cerebral vasospasm, a lasting cure continues to elude experts and the disease continues to wreak havoc on patients after aneurysmal SAH.

Transdural metastasis from adenocarcinoma of the prostate mimicking subdural hematoma: case report

BACKGROUND

Metastasis of prostatic adenocarcinoma to the nervous system is extremely rare and has been infrequently reported over the last several years. We describe the presentation, evaluation, and surgical intervention of a case of metastatic prostate carcinoma to the dura.

CASE DESCRIPTION

This patient presented with symptoms and physical findings consistent with a subacute subdural hematoma in the setting of recently diagnosed adenocarcinoma of the prostate. He underwent a craniotomy for presumed subdural hematoma. The pathologic diagnosis was consistent with metastatic prostatic carcinoma.

CONCLUSION

This case report demonstrates the need for broad differential diagnosis in the evaluation and treatment of patients presenting with seemingly straightforward subacute subdural hematomas.

Combined transsphenoidal and pterional craniotomy approach to giant pituitary tumors

OBJECTIVE

We describe a combined simultaneous approach to giant pituitary tumors and present a review of 10 patients undergoing this procedure with emphasis on patient selection, surgical technique, and results.

METHODS

A retrospective review was performed of patients who had undergone a combined, simultaneous transsphenoidal and pterional craniotomy approach to a giant pituitary adenoma. Visual findings, endocrine presentation, and tumor type were compiled. Tumor stage and grade (Hardy classification) were based on MRI and intraoperative findings.

RESULTS

Gross total resection of tumor was achieved in 4 of 10 patients, near total (>90%) in 2 of 10, and subtotal (80-90%) in 4. At the time of follow-up (average, 29.7 months; range, 17-44 months), stereotactic radiosurgery had been performed in 2 patients. Of the 9 patients who presented with visual field loss, all had improvement at 1-month follow-up. At 6 months follow-up, resolution was complete in 5 patients and partial in 4. No patient had worsening of vision. Hypopituitarism persisted in all 5 patients who presented with it preoperatively.

CONCLUSION

The combined, simultaneous transsphenoidal and pterional approach described is indicated for a small subset of patients with giant (>3 cm) clinically nonfunctional pituitary tumors who meet the criteria of tumor configuration outlined where the surgeon cannot achieve complete resection by a single approach. We propose adding a new Hardy's scheme subtype, Stage B-a, to describe giant pituitary tumors with a dumbbell configuration. Combining both craniotomy and transsphenoidal approaches may achieve the goal of tumor resection with less need for multiple sequential operations.

Transarterial Embolisation of Dural Arteriovenous Fistula Involving an Isolated Segment of the Superior Petrosal Sinus. A Case report

SUMMARY

This case report illustrates a relatively rare case of dural arteriovenous fistula (AVF) involving direct supply to an isolated segment of the superior petrosal sinus (SPS). Successful transarterial obliteration of the lesion was accomplished with only a liquid embolic agent with long-term angiographic and clinical cure.