Radiobiology of vestibular schwannomas: mechanisms of radioresistance and potential targets for therapeutic sensitization.

Vestibular schwannomas (VS) are benign tumors arising from the Schwann cells of cranial nerve VIII. Historically the prevailing therapy for patients with VS has been microsurgical resection. More recently, stereotactic radiosurgery (SRS) and fractionated stereotactic radiotherapy have gained acceptance as effective alternatives.

Beyond audiofacial morbidity after vestibular schwannoma surgery.

Object: Outcomes following vestibular schwannoma (VS) surgery have been extensively described; however, complication rates reported in the literature vary markedly. In addition, the majority of reports have focused on outcomes related to cranial nerves (CNs) VII and VIII. The objective of this study was to analyze reported morbidity unrelated to CNs VII and VIII following the resection of VS.

Molecular biology of familial and sporadic vestibular schwannomas: implications for novel therapeutics.

Vestibular schwannomas (VSs) are benign tumors arising from the sheath of cranial nerve VIII. The pathogenesis underlying most familial and sporadic VSs has been linked to a mutation in a single gene, the neurofibromin 2 (NF2) gene located on chromosome 22, band q11-13.1.

Immunological considerations of modern animal models of malignant primary brain tumors.

Recent advances in animal models of glioma have facilitated a better understanding of biological mechanisms underlying gliomagenesis and glioma progression. The limitations of existing therapy, including surgery, chemotherapy, and radiotherapy, have prompted numerous investigators to search for new therapeutic approaches to improve quantity and quality of survival from these aggressive lesions. One of these approaches involves triggering a tumor specific immune response.

A comprehensive analysis of hearing preservation after radiosurgery for vestibular schwannoma.

Object: Gamma Knife surgery (GKS) has evolved into a practical alternative to open microsurgical resection in the treatment of patients with vestibular schwannoma (VS). Hearing preservation rates in GKS series suggest very favorable outcomes without the possible acute morbidity associated with open microsurgery. To mitigate institutional and practitioner bias, the authors performed an analytical review of the published literature on the GKS treatment of vestibular schwannoma patients.

Large falcine meningioma fed by callosomarginal branch successfully removed following contralateral interhemispheric approach.

We report the case of a highly vascular facline meningioma removed following surgical ligation of a large callosomarginal feeding branch via a contralateral interhemispheric approach. Successfully addressing this vessel via a contralateral interhemispheric approach prior to any debulking allowed for en bloc Simpson Grade 1 tumor removal with minimal blood loss and short term tumor control without evidence of recurrence at 2 year follow up. A 56 year old man presented with first time generalized tonic-clonic seizure.

Risk profile associated with convexity meningioma resection in the modern neurosurgical era.

Object: Although meningiomas are commonly found along the supratentorial convexity, the risk profile associated with this subset of lesions in the modern neurosurgical era is unknown.

Methods: The authors retrospectively reviewed the clinical course of patients with supratentorial convexity meningiomas treated during the past 10 years. All patients had undergone MR imaging within 72 hours after surgery and at least 1 year of clinical follow-up.

The complement cascade: new avenues in stroke therapy.

Recent evidence has shown that after the initial occlusion, a large portion of stroke patients achieve some degree of reperfusion either through collateral circulation or clot dissolution. However, it appears that this reperfusion may lead to increased inflammation-induced damage. Even though the exact mechanism of this secondary injury is unclear, several experimental studies have indicated an intimate connection between complement and this secondary form of damage.

The natural history of untreated sporadic vestibular schwannomas: a comprehensive review of hearing outcomes.

Object: Observation is an important consideration when discussing management options for patients with vestibular schwannoma (VS). Most data regarding clinical outcomes after conservative management come from modestsized series performed at individual centers. The authors performed an analysis of the published literature on the natural history of VSs with respect to hearing outcome.

Facial nerve preservation after vestibular schwannoma Gamma Knife radiosurgery.

Objective: Facial nerve preservation is a critical measure of clinical outcome after vestibular schwannoma treatment. Gamma Knife radiosurgery has evolved into a practical treatment modality for vestibular schwannoma patients, with several reported series from a variety of centers. In this study, we report the results of an objective analysis of reported facial nerve outcomes after the treatment of vestibular schwannomas with Gamma Knife radiosurgery.

Bioethical considerations in translational research: primate stroke.

Controversy and activism have long been linked to the subject of primate research. Even in the midst of raging ethical debates surrounding fertility treatments, genetically modified foods and stem-cell research, there has been no reduction in the campaigns of activists worldwide. Playing their trade of intimidation aimed at ending biomedical experimentation in all animals, they have succeeded in creating an environment where research institutions, often painted as guilty until proven innocent, have avoided addressing the issue for fear of becoming targets.

Hearing preservation after stereotactic radiosurgery for vestibular schwannoma: a systematic review.

Radiosurgery has evolved into an effective alternative to microsurgical resection in the treatment of patients with vestibular schwannoma. We performed a systematic analysis of the literature in English on the radiosurgical treatment of vestibular schwannoma patients. A total of 254 published studies reported assessable and quantifiable outcome data of patients undergoing radiosurgery for vestibular schwannomas.

The role of complement in stroke therapy.

Cerebral ischemia and reperfusion initiate an inflammatory process which results in secondary neuronal damage. Immunomodulatory agents represent a promising means of salavaging viable tissue following stroke. The complement cascade is a potent mediator of inflammation which is activated following cerebral ischemia.

Vision salvage after resection of a giant meningioma in a patient with a loss in light perception.

Clinical approaches to the surgical management of optic chiasm compression stress quick action, as several case series have demonstrated minimal vision restoration following aggressive decompression in patients presenting more than 3 days after the onset of blindness. The authors here report the case of a 48-year-old woman who presented with near-complete binocular vision loss but regained visual function following surgical removal of a giant planum-tuberculum meningioma, which was performed 8 days after a documented loss in light perception. The interval between the patient's vision loss and successful vision-restoring decompressive surgery is the longest recorded to date in the literature.

Sarcoidosis of the pineal gland: an unusual presentation of neurosarcoidosis.

Introduction: Sarcoidosis is an inflammatory disease characterized by noncaseating granulomas that is rarely found as primary CNS pathology. We report an unusual case of sarcoidosis involving the pineal gland with radiographic, histopathology, and clinical data.

Case Report: A 45-year-old man without evidence of systemic sarcoidosis presented with a history of gradual onset of blurry vision and diplopia that progressed over 3 months.

Magnetic resonance imaging characteristics of pilomyxoid astrocytoma.

Objective: Pilomyxoid astrocytoma (PMA) is a recently identified pediatric low-grade neoplasm that was previously classified as pilocytic astrocytoma (PA), yet demonstrates unique histological features and more aggressive behavior. These tumors have been shown to have significantly shorter progression-free and overall survival probability than classical low-grade astrocytomas, as well as a high rate of cerebrospinal fluid (CSF) dissemination. This paper describes the radiographic features of PMA.

Pre-operative dopamine agonist therapy improves post-operative tumor control following prolactinoma resection.

Objective: Normalization of serum prolactin concentrations in patients with prolactinomas is an accepted endpoint of therapy. Clinical signs and symptoms of hyperprolactinemia are usually resolved when prolactin levels are lowered to within the normal range. While most patients are treated with dopamine agonist drugs, some patients require surgical resection of their tumors.

Pain as a symptom of peripheral nerve sheath tumors: clinical significance and future therapeutic directions.

Tumors arising from the supporting cells of peripheral nerve sheaths are relatively uncommon neoplasms, and as such many clinicians are unfamiliar with the details of their presentation, diagnosis and management. Further, little is known regarding the pathogenesis of these tumors, how they cause symptoms, and how to treat these symptoms. One classic symptom of peripheral nerve tumors is pain, however there has been little formal discussion regarding the significance of pain in this setting.

Neurologic assessment of somatosensory dysfunction following an experimental rodent model of cerebral ischemia.

The modified adhesive removal (sticky-tape) test is an assessment of somatosensory dysfunction following cerebral ischemia in rats. This test is less time consuming than the original protocol by virtue of requiring minimal pre-training. We present a detailed protocol describing how to conduct the modified adhesive removal (sticky-tape) test.

Preclinical evaluation of the neuroprotective effect of soluble complement receptor type 1 in a nonhuman primate model of reperfused stroke.

Object: Postischemic cerebral inflammatory injury has been extensively investigated in an effort to develop effective neuroprotective agents. The complement cascade has emerged as an important contributor to postischemic neuronal injury. Soluble complement receptor Type 1 (sCR1), a potent inhibitor of complement activation, has been shown to reduce infarct volume and improve functional outcome after murine stroke.

Alterations in plasma complement levels after human ischemic stroke.

Objective: Stroke is a leading cause of morbidity and mortality in the United States. Recent animal studies have implicated the complement system in cerebral ischemia/reperfusion injury and suggest that complement inhibition may improve stroke outcomes. To assess the applicability of these findings to humans, we evaluated the characteristics and time course of human complement activation after stroke.

Complement component C3 mediates inflammatory injury following focal cerebral ischemia.

The complement cascade has been implicated in ischemia/reperfusion injury, and recent studies have shown that complement inhibition is a promising treatment option for acute stroke. The development of clinically useful therapies has been hindered, however, by insufficient understanding of which complement subcomponents contribute to post-ischemic injury. To address this issue, we subjected mice deficient in selected complement proteins (C1q, C3, C5) to transient focal cerebral ischemia.