1/176. meningioma with sarcomatous change and hepatic metastasis.A 72-year-old patient had a meningotheliomatous meningioma that invaded through the skull and into temporalis muscle. One year following craniotomy for removal of the neoplasm, he developed headaches, diplopia, and proptosis of the left eye. biopsy of the orbital contents revealed a malignant supporting tissue neoplasm having a resemblance to the previous meningioma. No curative therapy was possible and the patient died 33 months after diagnosis. autopsy examination showed extensive residual intracranial neoplasm and a 3-cm metastasis in the liver. The metastatic tumor appeared similar to the meningioma and did not appear malignant histologically. The case illustrates the distinct histologic variations in meningiomas and the difficulties in predicting their biologic activity. Aggressive local behavior may indicate possible malignant areas in the neoplasm. Therefore, examination of the neoplasm should be thorough. Such a correlation may suggest malignant biologic potential.- - - - - - - - - - ranking = 1keywords = relation (Clic here for more details about this article) |
2/176. Surgical management of intraosseous skull base tumors with aid of Operating arm System.Invasion of bone and critical neurovascular structures often impedes complete resection of intraosseous skull base neoplasms, and these lesions tend to recur unless all infiltrated bone is removed. Evolving experience with image guidance over the past few years indicates the potential value of neuronavigation in skull base lesions diffusely infiltrating or fixed to bone structures. We report our early experience with the Radionics Operating arm System (OAS), specifically emphasizing its utility as an adjunct in the treatment of intraosseous skull base tumors, mainly meningiomas. In April 1995 the OAS was introduced into clinical use at the neurosurgical university clinic in Munster, germany. Since then, the system's utility has been explored in 10 patients out of the total neuronavigation series presenting with intraosseous skull base tumors (nine females and one male, mean age 47 years; nine meningiomas, one chordoma). For navigational planning, both 3-mm computed tomography scans and a set of 3-mm fat-suppression magnetic resonance images were chosen. At least four adhesive skin markers were used for system calibration. The system was technically usable in all cases in this small series. Because of the relative immobility of the bone structures and/or the tumor, no significant deviation from the preoperative registration accuracy was noted at the end of the procedures. The main advantages were easier localization and resection of infiltrated bone, which is often not grossly identifiable, even under the microscope. Our preliminary experience with the OAS suggests that image guidance is helpful in this type of lesion, providing better anatomical orientation during surgery and delineating tumor margins and their relation to critical neurovascular structures. The problem of a possible intracranial tumor and brain shift can be neglected in these lesions. The system facilitates resection by volumetric contour information, allowing more aggressive and complete resection.- - - - - - - - - - ranking = 3667.7961041833keywords = registration, relation (Clic here for more details about this article) |
3/176. Intraoperative validation of functional magnetic resonance imaging and cortical reorganization patterns in patients with brain tumors involving the primary motor cortex.OBJECT: The purpose of the present study was to compare the results of functional magnetic resonance (fMR) imaging with those of intraoperative cortical stimulation in patients who harbored tumors close to or involving the primary motor area and to assess the usefulness of fMR imaging in the objective evaluation of motor function as part of the surgical strategy in the treatment of these patients. methods: A total of 11 consecutive patients, whose tumors were close to or involving the central region, underwent presurgical blood oxygen level-dependent fMR imaging while performing a motor paradigm that required them to clench and spread their hands contra- and ipsilateral to the tumor. Statistical cross-correlation functional maps covering the primary and secondary motor cortical areas were generated and overlaid onto high-resolution anatomical MR images. Intraoperative electrical cortical stimulation was performed to validate the presurgical fMR imaging findings. In nine (82%) of 11 patients, the anatomical fMR imaging localization of motor areas could be verified by intraoperative electrical cortical stimulation. In seven patients two or more activation sites were demonstrated on fMR imaging, which were considered a consequence of reorganization phenomena of the motor cortex: contralateral primary motor area (nine patients), contralateral premotor area (four patients), ipsilateral primary motor area (two patients), and ipsilateral premotor area (four patients). CONCLUSIONS: Functional MR imaging can be used to perform objective evaluation of motor function and surgical planning in patients who harbor lesions near or involving the primary motor cortex. Correlation between fMR imaging findings and the results of direct electrical brain stimulation is high, although not 100%. Based on their study, the authors believe that cortical reorganization patterns of motor areas might explain the differences in motor function and the diversity of postoperative motor function among patients with central tumors.- - - - - - - - - - ranking = 2keywords = relation (Clic here for more details about this article) |
4/176. meningioma with meningioangiomatosis: a condition mimicking invasive meningiomas in children and young adults: report of two cases and review of the literature.Meningioangiomatosis is a malformative meningovascular proliferation that occurs sporadically and in patients with neurofibromatosis type 2. Its histologic features of perivascular proliferation of elongated fibroblast and meningothelial cells trapping islands of gliotic cortex may be erroneously interpreted as invasion when an overlying meningioma is present. We report two cases of meningioangiomatosis associated with meningioma and review the literature on the subject for a total of six cases. The age of patients ranged from 9 months to 33 years. All cases were single lesions, and none had clinical evidence of neurofibromatosis type 2. Meningiomas in children have been regarded as having more aggressive behavior than their adult counterparts, with more frequent invasion of the underlying brain. The lack of correlation between brain invasion and recurrence observed in series of meningiomas in young patients may suggest that some of these lesions are meningioangiomatosis associated with meningioma rather than invasive meningiomas.- - - - - - - - - - ranking = 1keywords = relation (Clic here for more details about this article) |
5/176. Clonal analysis of a case of multiple meningiomas using multiple molecular genetic approaches: pathology case report.OBJECTIVE: Multiple meningiomas are uncommon brain tumors occurring concurrently in several intracranial locations in the same patient. In the present study, we determined the clonality, methylation status of deoxyribonucleic acid, and relationship of genetic alterations in eight meningiomas from one female patient. methods: Six molecular genetic techniques, including two methylation-based clonality assays and one transcription-based clonality assay, methylation analysis of cpg islands by methylation-specific polymerase chain reaction, loss of heterozygosity, microsatellite instability, and mutational analysis of the NF2 gene on chromosome 22, were used in comparative investigations on clonality and genetic alterations. RESULTS: The presence of clonal tumor cells was demonstrated by 1) loss of the same copy of chromosome 22 in all eight tumors; 2) transcription of the human AR gene from the same allele in six of eight tumors; 3) a common unmethylated allele at the AR locus in all eight tumors; and 4) the identical single-basepair insertion mutation in exon 9 of the NF2 gene in six of eight tumors. In addition, loss of a copy of the x chromosome in one tumor nodule and microsatellite instability in another nodule were observed. CONCLUSION: Taken together, this case of multiple meningiomas was most likely monoclonal in origin. Loss of chromosome 22 was an early event during the development of multiple meningiomas and was followed by mutations at the NF2 locus. Later events, including loss of the x chromosome, variation of AR gene expression, or microsatellite instability, may also have played a role in the development of multiple meningiomas in this patient.- - - - - - - - - - ranking = 1keywords = relation (Clic here for more details about this article) |
6/176. Planning and simulation of neurosurgery in a virtual reality environment.OBJECTIVE: To report our experience with preoperative neurosurgical planning in our stereoscopic virtual reality environment for 21 patients with intra- and extra-axial brain tumors and vascular malformations. methods: A neurosurgical planning system called VIVIAN (Virtual Intracranial Visualization and Navigation) was developed for the Dextroscope, a virtual reality environment in which the operator reaches with both hands behind a mirror into a computer-generated stereoscopic three-dimensional (3-D) object and moves and manipulates the object in real time with natural 3-D hand movements. Patient-specific data sets from multiple imaging techniques (magnetic resonance imaging, magnetic resonance angiography, magnetic resonance venography, and computed tomography) were coregistered, fused, and displayed as a stereoscopic 3-D object. A suite of 3-D tools accessible inside the VIVIAN workspace enabled users to coregister data, perform segmentation, obtain measurements, and simulate intraoperative viewpoints and the removal of bone and soft tissue. RESULTS: VIVIAN was used to plan neurosurgical procedures primarily in difficult-to-access areas, such as the cranial base and the deep brain. The intraoperative and virtual reality 3-D scenarios correlated well. The VIVIAN system substantially contributed to surgical planning by 1) providing a quick and better understanding of intracranial anatomic and abnormal spatial relationships, 2) simulating the craniotomy and the required cranial base bone work, and 3) simulating intraoperative views. CONCLUSION: The VIVIAN system allows users to work with complex imaging data in a fast, comprehensive, and intuitive manner. The 3-D interaction of this virtual reality environment is essential to the efficient assembly of surgically relevant spatial information from the data derived from multiple imaging techniques. The usefulness of the system is highly dependent on the accurate coregistration of the data and the real-time speed of the interaction.- - - - - - - - - - ranking = 3667.7961041833keywords = registration, relation (Clic here for more details about this article) |
7/176. Melanocytoma of the left optic nerve head and right retrobulbar optic neuropathy compressed by a tuberculum sellae meningioma.A 40-year-old woman had a highly pigmented, slightly elevated tumor on the left optic disc. She had no visual disturbance in the left eye. The tumor was stationary for 5 years. At age 45 years, she complained of decreased visual acuity in the right eye. magnetic resonance imaging showed a right-shifted homogeneous lesion at the tuberculum sellae. Histopathologic study of the excised lesion revealed interlacing bundles of spindle-shaped fibroblast-like cells with whorl formation. We believe that a relationship between melanocytoma of the optic nerve head and a tuberculum sellae meningioma may exist rather than a chance occurrence, as previously suggested by others.- - - - - - - - - - ranking = 1keywords = relation (Clic here for more details about this article) |
8/176. Vascular endothelial growth factor and malignant transformation of a meningioma: case report.Although meningiomas are common benign intracranial tumors which grow slowly, we occasionally encountered aggressive or malignant ones. One of these cases showed an interesting relationship to vascular endothelial growth factor (VEGF). A 39-year-old woman underwent resection of a sphenoid ridge meningioma; the residual tumor showed evidence of malignant transformation 14 years later. We immunohistochemically examined six successive surgical specimens plus the autopsy specimen of this patient's tumor for proliferative potential, vascularity, and expression of various growth factors. In the latter stage of clinical courses, proliferative potential and vascularity was seen to increase year by year. Expression of VEGF was upregulated and correlated with vascularity. On the other hand, basic fibroblast growth factor (bFGF), platelet-derived growth factor (PDGF), and epidermal growth factor (EGF) were not overexpressed in this tumor. This case suggests that overexpression of VEGF and increased angiogenic potential might be involved in malignant transformation of meningiomas.- - - - - - - - - - ranking = 1keywords = relation (Clic here for more details about this article) |
9/176. cerebrospinal fluid oligoclonal IgG bands in patients with spinal arteriovenous malformation and structural central nervous system lesions.OBJECTIVE: To investigate the incidence and characteristics of patients with structural central nervous system (CNS) lesions and cerebrospinal fluid oligoclonal IgG bands. DESIGN: A retrospective study. METHOD: The medical records of patients with cerebrospinal fluid oligoclonal IgG bands were evaluated for the presence of structural CNS lesions, their location and cause, and for clinical characteristics. SETTING: cerebrospinal fluid oligoclonal IgG bands were examined in the Neuroimmunology Laboratory, Hadassah University Hospital, Jerusalem, israel. patients: Two hundred seventy of 570 patients with positive cerebrospinal fluid oligoclonal IgG bands were available for analysis. Twenty patients had structural CNS lesions. RESULTS: Twenty (7.5%) of the 270 patients had structural CNS lesions: 3 patients had spinal arteriovenous malformation; 5 patients had tumors; 9 patients had compressive cervical myelopathy. Traumatic leukomalacia, arnold-chiari malformation type 1, and CNS hemosiderosis were present in 1 patient each. In 2 patients (1 patient with recurrent meningioma and 1 patient with posttraumatic encephalomalacia) the presence of a structural CNS lesion was followed by the development of multiple sclerosis. In all 3 patients with spinal arteriovenous malformation, oligoclonal IgG identification prolonged the time to diagnosis and therapy, which varied from a few weeks to 3 years. CONCLUSIONS: Structural CNS lesions, responsible for the neurological disorder, were present in 20 patients (7.5%) with cerebrospinal fluid oligoclonal IgG bands. The mechanism underlying oligoclonal IgG presence in spinal arteriovenous malformation and the coexistence of multiple sclerosis and structural CNS lesions is unknown, but may be related to recurrent tissue damage with repeated presentation of CNS antigens to the immune system.- - - - - - - - - - ranking = 0.4569061657029keywords = record (Clic here for more details about this article) |
10/176. Secondary intracranial meningiomas after high-dose cranial irradiation: report of five cases and review of the literature.PURPOSE: To review cases of secondary intracranial meningiomas following high-dose cranial irradiation (>/= 10 Gy) identified in slovenia between 1968 and 1998, to determine their histological profile and to review the literature on this topic. methods AND MATERIALS: Personal files of patients treated for secondary intracranial meningioma during a 31-year period were reviewed. In cases which met the criteria for radiation-induced tumors, steroid hormone receptor and Ki-67 status were analyzed. For the literature review, computerized database systems and reference lists from respective publications were used. RESULTS: Five patients (2 females, 3 males), 3-11 years old at the time of cranial irradiation, developed secondary meningioma after a latency period of 9.5-31.5 years. Three patients had multiple tumors and 2 developed recurrent disease. Of 9 histologically examined tumors, 5 were graded as benign and 4 as atypical meningiomas, with Ki-67 proliferative index 3.2 /- 3.6 and 10 /- 6, respectively. The ratio between positive and negative meningiomas regarding immunostaining for progesterone and estrogen receptors was eight-to-one and six-to-three, respectively. Cumulative actuarial risk of secondary meningioma in a cohort of 445 children 16 years or younger treated with high-dose cranial irradiation between 1968 and 1990 in slovenia at 10, 20, and 25 years was 0.53%, 1.2%, and 8.18%, respectively. Out of 126 cases of radiation-induced meningiomas reported, 57% were females and 43% were males, with mean age at presentation 33 /- 17.3 years. The majority (68%) of patients was irradiated during childhood. The latency period was significantly shorter in those who aged 5 years or less at the time of cranial irradiation (p = 0.04), and in those with atypical/anaplastic tumor (p = 0.01). Correlation between radiation dose and latency period could not be found. CONCLUSION: Secondary meningiomas following high-dose cranial irradiation are characterized by younger age at presentation, by higher male-to-female ratio and by biologically more aggressive variants compared to primary spontaneous meningiomas. Latency period correlated with the age at the time of cranial irradiation and with tumor grade but not with irradiation dose. Ki-67 immunoreactivity correlated with histological grade. The progesterone and estrogen receptor immunoreactivity was high. The risk for development of secondary meningioma after high-dose cranial irradiation was increasing with the time of follow-up.- - - - - - - - - - ranking = 1keywords = relation (Clic here for more details about this article) |
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