Meningioma: A relatively common neoplasm of the CENTRAL NERVOUS SYSTEM that arises from arachnoidal cells. The majority are well differentiated vascular tumors which grow slowly and have a low potential to be invasive, although malignant subtypes occur. Meningiomas have a predilection to arise from the parasagittal region, cerebral convexity, sphenoidal ridge, olfactory groove, and SPINAL CANAL. (From DeVita et al., Cancer: Principles and Practice of Oncology, 5th ed, pp2056-7)Meningeal Neoplasms: Benign and malignant neoplastic processes that arise from or secondarily involve the meningeal coverings of the brain and spinal cord.Arachnoid: A delicate membrane enveloping the brain and spinal cord. It lies between the PIA MATER and the DURA MATER. It is separated from the pia mater by the subarachnoid cavity which is filled with CEREBROSPINAL FLUID.Skull Neoplasms: Neoplasms of the bony part of the skull.Hyperostosis: Increase in the mass of bone per unit volume.Skull Base Neoplasms: Neoplasms of the base of the skull specifically, differentiated from neoplasms of unspecified sites or bones of the skull (SKULL NEOPLASMS).Cerebellopontine Angle: Junction between the cerebellum and the pons.Brain Neoplasms: Neoplasms of the intracranial components of the central nervous system, including the cerebral hemispheres, basal ganglia, hypothalamus, thalamus, brain stem, and cerebellum. Brain neoplasms are subdivided into primary (originating from brain tissue) and secondary (i.e., metastatic) forms. Primary neoplasms are subdivided into benign and malignant forms. In general, brain tumors may also be classified by age of onset, histologic type, or presenting location in the brain.Dura Mater: The outermost of the three MENINGES, a fibrous membrane of connective tissue that covers the brain and the spinal cord.Genes, Neurofibromatosis 2: Tumor suppressor genes located on the long arm of human chromosome 22. Mutation or loss of these genes causes NEUROFIBROMATOSIS 2.Magnetic Resonance Imaging: Non-invasive method of demonstrating internal anatomy based on the principle that atomic nuclei in a strong magnetic field absorb pulses of radiofrequency energy and emit them as radiowaves which can be reconstructed into computerized images. The concept includes proton spin tomographic techniques.Neuroma, Acoustic: A benign SCHWANNOMA of the eighth cranial nerve (VESTIBULOCOCHLEAR NERVE), mostly arising from the vestibular branch (VESTIBULAR NERVE) during the fifth or sixth decade of life. Clinical manifestations include HEARING LOSS; HEADACHE; VERTIGO; TINNITUS; and FACIAL PAIN. Bilateral acoustic neuromas are associated with NEUROFIBROMATOSIS 2. (From Adams et al., Principles of Neurology, 6th ed, p673)Optic Nerve Neoplasms: Benign and malignant neoplasms that arise from the optic nerve or its sheath. OPTIC NERVE GLIOMA is the most common histologic type. Optic nerve neoplasms tend to cause unilateral visual loss and an afferent pupillary defect and may spread via neural pathways to the brain.Hemangiopericytoma: A tumor composed of spindle cells with a rich vascular network, which apparently arises from pericytes, cells of smooth muscle origin that lie around small vessels. Benign and malignant hemangiopericytomas exist, and the rarity of these lesions has led to considerable confusion in distinguishing between benign and malignant variants. (From Dorland, 27th ed; DeVita Jr et al., Cancer: Principles & Practice of Oncology, 3d ed, p1364)Neurosurgical Procedures: Surgery performed on the nervous system or its parts.Ear Neoplasms: Tumors or cancer of any part of the hearing and equilibrium system of the body (the EXTERNAL EAR, the MIDDLE EAR, and the INNER EAR).Neurofibromatosis 2: An autosomal dominant disorder characterized by a high incidence of bilateral acoustic neuromas as well as schwannomas (NEURILEMMOMA) of other cranial and peripheral nerves, and other benign intracranial tumors including meningiomas, ependymomas, spinal neurofibromas, and gliomas. The disease has been linked to mutations of the NF2 gene (GENES, NEUROFIBROMATOSIS 2) on chromosome 22 (22q12) and usually presents clinically in the first or second decade of life.Craniotomy: Any operation on the cranium or incision into the cranium. (Dorland, 28th ed)Cerebral Ventricle Neoplasms: Neoplasms located in the brain ventricles, including the two lateral, the third, and the fourth ventricle. Ventricular tumors may be primary (e.g., CHOROID PLEXUS NEOPLASMS and GLIOMA, SUBEPENDYMAL), metastasize from distant organs, or occur as extensions of locally invasive tumors from adjacent brain structures.Neurilemmoma: A neoplasm that arises from SCHWANN CELLS of the cranial, peripheral, and autonomic nerves. Clinically, these tumors may present as a cranial neuropathy, abdominal or soft tissue mass, intracranial lesion, or with spinal cord compression. Histologically, these tumors are encapsulated, highly vascular, and composed of a homogenous pattern of biphasic fusiform-shaped cells that may have a palisaded appearance. (From DeVita Jr et al., Cancer: Principles and Practice of Oncology, 5th ed, pp964-5)Tomography, X-Ray Computed: Tomography using x-ray transmission and a computer algorithm to reconstruct the image.Meninges: The three membranes that cover the BRAIN and the SPINAL CORD. They are the dura mater, the arachnoid, and the pia mater.Foramen Magnum: The large hole at the base of the skull through which the SPINAL CORD passes.Chromosomes, Human, Pair 22: A specific pair of GROUP G CHROMOSOMES of the human chromosome classification.Neurofibromin 2: A membrane protein homologous to the ERM (Ezrin-Radixin-Moesin) family of cytoskeleton-associated proteins which regulate physical properties of membranes. Alterations in neurofibromin 2 are the cause of NEUROFIBROMATOSIS 2.
MeningiomaArachnoid granulation: Arachnoid granulations (or arachnoid villi) are small protrusions of the arachnoid (the thin second layer covering the brain) through the dura mater (the thick outer layer). They protrude into the venous sinuses of the brain, and allow cerebrospinal fluid (CSF) to exit the sub-arachnoid space and enter the blood stream.Ankylosing hyperostosisUniversity of Miami Division of Surgical Neurooncology: The Division of Surgical Neurooncology in the Department of Neurological Surgery and Sylvester Comprehensive Cancer Center at the University of Miami is one of the largest and most complete programs for brain tumor treatment in the United States. As the only academic medical center in the region, the University of Miami offers a unique and comprehensive approach to these conditions, with interdisciplinary discussion between neurosurgery, neurology, radiation oncology, and medical oncology.Neurooncology: Neuro-oncology is the study of brain and spinal cord neoplasms, many of which are (at least eventually) very dangerous and life-threatening (astrocytoma, glioma, glioblastoma multiforme, ependymoma, pontine glioma, and brain stem tumors are among the many examples of these). Among the malignant brain cancers, gliomas of the brainstem and pons, glioblastoma multiforme, and high-grade (highly anaplastic) astrocytoma are among the worst.Falx cerebri: The falx cerebri is also known as the cerebral falx, named from its sickle-like form. It is a large, crescent-shaped fold of meningeal layer of dura mater that descends vertically in the longitudinal fissure between the cerebral hemispheres.HyperintensityVestibular schwannomaInfantile hemangiopericytoma: Infantile hemangiopericytoma (also known as "Congenital hemangiopericytoma") is a cutaneous condition characterized by single or multiple dermal and subcutaneous nodules that may be alarmingly large at birth or grow rapidly.Bifrontal craniotomy: a bifrontal craniotomy is a surgical process which is used to target different tumors or malfunctioning areas of the brain.http://www.Ludwig G. KempeAntoni Jan GoetzDense artery sign: In medicine, the dense artery sign or hyperdense artery sign is a radiologic sign seen on computer tomography (CT) scans suggestive of early ischemic stroke. In earlier studies of medical imaging in patients with strokes, it was the earliest sign of ischemic stroke in a significant minority of cases.C14 Timberwolf: The C14 Timberwolf MRSWS (Medium Range Sniper Weapon System) is a bolt action sniper rifle built by the Canadian arms company PGW Defence Technologies Inc. In 2005 they won the contract to supply the Canadian Forces Land Command with the C14 Timberwolf MRSWS for $4.Merlin (bicycles): Merlin titanium|thumb|Merlin titanium MTB frame
(1/1193) SPARC: a potential diagnostic marker of invasive meningiomas.
SPARC, a secreted, extracellular matrix-associated protein implicated in the modulation of cell adhesion and migration, was evaluated as a marker for invasive meningiomas. Although the majority of meningiomas are clinically and morphologically benign, approximately 10% progress into atypical and malignant tumors, according to the standard criteria. However, a subset of meningiomas presents as histomorphologically benign tumors (WHO grade I), but they are clinically invasive. It has been suggested that these tumors should be classified as malignant, and that the patients may require adjuvant therapy and closer follow up. Unfortunately, a significant number of these tumors may not be recognized because the surgical specimen used to assess the grade of a tumor lacks the infiltrative interface with the brain, which is currently necessary to determine its invasive character. Therefore, a marker of heightened invasiveness would greatly facilitate the identification of this subset of patients. In this study, the immunohistochemical expression of SPARC in benign, noninvasive primary meningiomas was compared with its expression in invasive, aggressive, primary and recurrent meningiomas. SPARC was not expressed in the 9 benign, noninvasive tumors, but was highly expressed in the 20 invasive tumors, regardless of the grade. The findings suggest that SPARC is a potential diagnostic marker of invasive meningiomas and is capable of distinguishing the histomorphologically benign noninvasive from the histomorphologically benign but invasive meningiomas, in the absence of the infiltrative interface. (+info)
(2/1193) Hemangioblastoma mimicking tentorial meningioma: preoperative embolization of the meningeal arterial blood supply--case report.
A 72-year-old male presented with a primary hemangioblastoma of the posterior fossa with unusual dural attachment and meningeal arterial blood supply from the external carotid artery and marginal tentorial artery. Preoperative embolization facilitated complete resection of the tumor with no resultant neurological deficit. Hemangioblastoma must be included in the differential diagnosis of tumors with dural involvement. Preoperative embolization is very useful in such tumors. (+info)
(3/1193) Cerebral veins: comparative study of CT venography with intraarterial digital subtraction angiography.
BACKGROUND AND PURPOSE: Our objective was to compare the reliability of CT venography with intraarterial digital subtraction angiography (DSA) in imaging cerebral venous anatomy and pathology. METHODS: In 25 consecutive patients, 426 venous structures were determined as present, partially present, or absent by three observers evaluating CT multiplanar reformatted (MPR) and maximum intensity projection (MIP) images. These results were compared with the results from intraarterial DSA and, in a second step, with the results of an intraobserver consensus. In addition, pathologic conditions were described. RESULTS: Using DSA as the standard of reference, MPR images had an overall sensitivity of 95% (specificity, 19%) and MIP images a sensitivity of 80% (specificity, 44%) in depicting the cerebral venous anatomy. On the basis of an intraobserver consensus including DSA, MPR, and MIP images (415 vessels present), the sensitivity/specificity was 95%/91% for MPR, 90%/100% for DSA, and 79%/91% for MIP images. MPR images were superior to DSA images in showing the cavernous sinus, the inferior sagittal sinus, and the basal vein of Rosenthal. Venous occlusive diseases were correctly recognized on both MPR and MIP images. Only DSA images provided reliable information of invasion of a sinus by an adjacent meningioma. CONCLUSION: CT venography proved to be a reliable method to depict the cerebral venous structures. MPR images were superior to MIP images. (+info)
(4/1193) A new technique of surface anatomy MR scanning of the brain: its application to scalp incision planning.
BACKGROUND AND PURPOSE: Surface anatomy scanning (SAS) is an established technique for demonstrating the brain's surface. We describe our experience in applying SAS with superposition of MR venograms to preoperative scalp incision planning. METHODS: In 16 patients, scalp incision planning was done by placing a water-filled plastic tube at the intended incision site when we performed SAS using half-Fourier single-shot fast spin-echo sequences. Two-dimensional phase-contrast MR angiograms were obtained to demonstrate the cortical veins and then superimposed upon the SAS images. The added images were compared with surgical findings using a four-point grading scale (0 to 3, poor to excellent). RESULTS: In each case, neurosurgeons could easily reach the lesion. Surgical findings correlated well with MR angiogram-added SAS images, with an average score of 2.56. CONCLUSION: Our simple technique is a useful means of preoperatively determining brain surface anatomy and can be used to plan a scalp incision site. (+info)
(5/1193) In vivo hydrogen-1 magnetic resonance spectroscopy study of human intracranial tumors.
OBJECTIVE: To investigate the metabolic changes, pathological state and histological types of intracranial tumors with hydrogen-1 magnetic resonance spectroscopy (H-1 MRS). METHODS: Thirteen patients with intracranial tumors were studied with localized proton magnetic resonance spectroscopy (H-1MRS), in vivo. All spectra were obtained with a 2.0 T whole body MR imaging system. RESULTS: All the spectra of these tumors exhibited high ratios of choline (Cho)/creatine (Cr) and Cho/N-acetyl aspartate (NAA), and histologically different tumors showed obvious variations in the metabolite ratios. Significant differences of Cho/Cr ratio were found between meningiomas and astrocytomas by statistical evaluation. The spectra obtained after operation were remarkably different from those before operation. CONCLUSION: H-1 MRS can serve as a non-invasive clinical test for therapeutic and prognostic uses for intracranial tumors. (+info)
(6/1193) NF2 gene mutations and allelic status of 1p, 14q and 22q in sporadic meningiomas.
Formation of meningiomas and their progression to malignancy may be a multi-step process, implying accumulation of genetic mutations at specific loci. To determine the relationship between early NF2 gene inactivation and the molecular mechanisms that may contribute to meningioma tumor progression, we have performed deletion mapping analysis at chromosomes 1, 14 and 22 in a series of 81 sporadic meningiomas (54 grade I (typical), 25 grade II (atypical) and two grade III (anaplastic)), which were also studied for NF2 gene mutations. Single-strand conformational polymorphism analysis was used to identify 11 mutations in five of the eight exons of the NF2 gene studied. All 11 tumors displayed loss of heterozygosity (LOH) for chromosome 22 markers; this anomaly was also detected in 33 additional tumors. Twenty-nine and 23 cases were characterized by LOH at 1p and 14q, respectively, mostly corresponding to aggressive tumors that also generally displayed LOH 22. All three alterations were detected in association in seven grade II and two grade III meningiomas, corroborating the hypothesis that the formation of aggressive meningiomas follows a multi-step tumor progression model. (+info)
(7/1193) Clinical features and outcomes in patients with non-acoustic cerebellopontine angle tumours.
OBJECTIVES: Non-acoustic tumours of the cerebellopontine angle differ from vestibular schwannomas in their prevalence, clinical features, operative management, and surgical outcome. These features were studied in patients presenting to the regional neuro-otological unit. METHODS: A retrospective analysis of clinical notes identified 42 patients with non-acoustic tumours of the cerebellopontine angle. Data were extracted regarding presenting clinical features, histopathological data after surgical resection, surgical morbidity and mortality, and clinical outcome (mean 32 months follow up). RESULTS: The study group comprised 25 meningiomas (60%), 12 epidermoid cysts/cholesteatomata (28%), and five other tumours. In patients with meningiomas, symptoms differed considerably from patients presenting with vestibular schwannomas. Cerebellar signs were present in 52% and hearing loss in only 68%. Twenty per cent of patients had hydrocephalus at the time of diagnosis. After surgical resection, normal facial nerve function was preserved in 75% of cases. In the epidermoid group, fifth, seventh, and eighth nerve deficits were present in 42%, 33%, and 66% respectively. There were no new postoperative facial palsies. There were two recurrences (17%) requiring reoperation. Overall, there were two perioperative deaths from pneumonia and meningitis. CONCLUSIONS: Patients with non-acoustic lesions of the cerebellopontine angle often present with different symptoms and signs from those found in patients with schwannomas. Hearing loss is less prevalent and cerebellar signs and facial paresis are more common as presenting features. Hydrocephalus is often present in patients presenting with cerebellopontine angle meningiomas. Non-acoustic tumours can usually be resected with facial nerve preservation. (+info)
(8/1193) Role of p53 gene mutation in tumor aggressiveness of intracranial meningiomas.
The mutations that occur in the p53 tumor suppressor gene have been studied in various human malignant tumors. However, little is known about this gene in meningiomas. To investigate the relationship and frequency of p53 gene mutations, the p53 polymerase chain reaction-single stranded conformational polymorphism (PCR-SSCP) and immunohistochemical study were performed on the 41 intracranial meningiomas (21 benign, 11 atypical, and 9 malignant). The higher the p53 protein expression rate, the poorer the histologic grade (9.5%, 72.7%, and 88.9% in benign, atypical and malignant meningioma, respectively) (p=0.000). The p53 protein expression rate was higher in recurrent meningioma (71.4%) than in nonrecurrent meningioma (10.5%) (p=0.002). PCR-SSCP method was performed in positive p53 protein immunoreactivity cases. p53 gene mutation rate was higher in the atypical (62.5%) and malignant (25%) meningiomas than in the benign meningioma (0%) (p=0.232). Also, the rate was higher in recurrent menigioma (20%) than in nonrecurrent meningioma (0%) (o=0.495). Among five to eight exons of the p53 gene, the mutation was observed on exon 7 more frequently. In conclusion, p53 immunoreactivity and p53 gene mutation are closely correlated with histologic grade and histologic atypia of intracranial meningiomas. p53 gene mutation would be considered as a useful marker to detect the progression of intracranial meningiomas. (+info)
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