1/69. Gliomatosis cerebri with secondary glioblastoma formation: report of two cases.The clinicopathological features of two cases of gliomatosis cerebri associated with secondary glioblastoma formation are reported. In both cases, glial cells were diffusely distributed in the supra- and infratentorial regions and underlying brain structures were preserved from the onset. In spite of such diffuse distribution of neoplastic glial cells, similar to that observed in low-grade astrocytoma, in both cases the tumor underwent complete remission after radiotherapy. However, the tumor recurred as a localized glioblastoma in both cases, 37 months (case 1) and 7 months (case 2) after the radiotherapy. In both cases, recurrence was accompanied by prominent dissemination of CSF. The recurrent tumors were radiation resistant, and the patients' conditions deteriorated rapidly after recurrence. The present two cases demonstrated that gliomatosis cerebri, classified among brain tumors of unknown origin by the world health organization, may transform into highly proliferative circumscribed tumors, in spite of their good response to radiotherapy. Examination of pathological features and their correlation with MRI findings may allow us to better understand the response to radiotherapy and the process of recurrence.- - - - - - - - - - ranking = 1keywords = relation (Clic here for more details about this article) |
2/69. 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) |
3/69. glioblastoma multiforme at the site of metal splinter injury: a coincidence? Case report.The authors report the case of a man who had suffered a penetrating metal splinter injury to the left frontal lobe at 18 years of age. Thirty-seven years later the patient developed a left-sided frontal tumor at the precise site of the meningocerebral scar and posttraumatic defect. Histological examination confirmed a glioblastoma multiforme adjacent to the dural scar and metal splinters. In addition, a chronic abscess from which propionibacterium acnes was isolated was found within the glioma tissue. The temporal and local association of metal splinter injury with chronic abscess, scar formation, and malignant glioma is highly suggestive of a causal relationship between trauma and the development of a malignant brain tumor.- - - - - - - - - - ranking = 1keywords = relation (Clic here for more details about this article) |
4/69. 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 = 0.3612093210045keywords = record (Clic here for more details about this article) |
5/69. Registration of functional and anatomical MRI: accuracy assessment and application in navigated neurosurgery.OBJECTIVE: A procedure for acquisition, automated registration, and fusion of functional and anatomical magnetic resonance images is presented. Its accuracy is quantitatively assessed using a publicly available gold standard. A patient case is used to illustrate the technique's clinical usefulness in image-guided neurosurgery. MATERIALS AND methods: Before and after functional MRI (fMRI) acquisition, additional anatomical images were acquired at spatial locations identical to those of the functional images (5-10 slices) for the purpose of voxel-based image registration. Registration accuracy of the anatomical volumes and high-resolution 3D MRI volumes (MP-rage imaging) was quantified using adapted data (8 patients) originating from the Vanderbilt Retrospective Registration Evaluation Project (NIH project 1 R01 NS33926-02). Selecting three subsets of slices from that data (5 slices/6 mm slice distance, 10 slices/3 mm distance, and 10 slices/6 mm distance), the small number of images available from fMRI acquisition was taken into account. Accuracies in registering these sparse data sets were then compared to the accuracy achieved using complete data. For clinical patient data (16 patients), fMRI images were fused with MP-rage images, thereby integrating anatomical images with information about the locations of functional areas. The resulting images were used for planning and navigation during tumor resections using an operating microscope (MKM, Zeiss). RESULTS: Quantitative analysis showed no loss of registration accuracy due to a reduced number of slices, regardless of whether 5 or 10 slices were used. For small-volume coverage in the anatomical images (thickness 24 mm), registration of one patient failed, and this could easily be identified by visual inspection. No failures were experienced when 54 mm was covered. In the clinical environment, all 16 interventions using fused fMRI and MRI data were successful. CONCLUSIONS: Automatic registration of functional and high-resolution anatomical MRI was found to be sufficiently accurate and reliable for use in stereotactic neurosurgery.- - - - - - - - - - ranking = 45454.422187863keywords = registration (Clic here for more details about this article) |
6/69. A preliminary study of angiogenesis in paediatric glioblastoma multiforme and its correlation with survival.OBJECTS: There is a distinct challenge in bringing modern insights into glial tumour genesis to bear on improved outcomes for patients. Insights provided by neuroncological, neuroradiological, neuropathological, and neurosurgical investigations may offer significant advantages in the management of paediatric GBM. The goal of this study was to evaluate angiogenesis as a potential indicator of survival in paediatric glioblastoma multiforme (GBM). methods: Angiogenesis was evaluated in six cases of paediatric GBM with multiple criteria, including contrast enhancement on preoperative CT scan, histological vascular hyperplasia (VH) and endothelial proliferation (EP) and immunohistochemical tenascin-C (TN-C) expression. We employed a semiquantitative scale, ranging from not detected (zero) to marked ( 3), for each investigational parameter. We evaluated the influence of angiogenesis on survival in each case. CONCLUSIONS: In this preliminary study, angiogenesis provided information that correlated with survival, albeit in a limited number of patients. As we gain better understanding of the molecular biology of brain tumours, with the multitude of genetic alterations and growth factors new therapeutic approaches may emerge, which may hold the promise for cure.- - - - - - - - - - ranking = 4keywords = relation (Clic here for more details about this article) |
7/69. diffusion-tensor imaging of white matter tracts in patients with cerebral neoplasm.OBJECT: Preserving vital cerebral function while maximizing tumor resection is a principal goal in surgical neurooncology. Although functional magnetic resonance imaging has been useful in the localization of eloquent cerebral cortex, this method does not provide information about the white matter tracts that may be involved in invasive, intrinsic brain tumors. Recently, diffusion-tensor (DT) imaging techniques have been used to map white matter tracts in the normal brain. The aim of this study was to demonstrate the role of DT imaging in preoperative mapping of white matter tracts in relation to cerebral neoplasms. methods: Nine patients with brain malignancies (one pilocytic astrocytoma, five oligodendrogliomas, one low-grade oligoastrocytoma, one Grade 4 astrocytoma, and one metastatic adenocarcinoma) underwent DT imaging examinations prior to tumor excision. Anatomical information about white matter tract location, orientation, and projections was obtained in every patient. Depending on the tumor type and location, evidence of white matter tract edema (two patients), infiltration (two patients), displacement (five patients), and disruption (two patients) could be assessed with the aid of DT imaging in each case. CONCLUSIONS: diffusion-tensor imaging allowed for visualization of white matter tracts and was found to be beneficial in the surgical planning for patients with intrinsic brain tumors. The authors' experience with DT imaging indicates that anatomically intact fibers may be present in abnormal-appearing areas of the brain. Whether resection of these involved fibers results in subtle postoperative neurological deficits requires further systematic study.- - - - - - - - - - ranking = 1keywords = relation (Clic here for more details about this article) |
8/69. Impact of brain shift on intraoperative neurophysiological monitoring with cortical strip electrodes.BACKGROUND: intraoperative neurophysiological monitoring has become the standard procedure for locating eloquent regions of the brain. Such continuous electrical stimulation of motor pathways is usually applied by means of flat silicon-embedded electrodes placed directly on the motor cortex. However, shifting of the silicon strip on the cortical surface as well as electrode displacement due to brain shift underneath the electrode can lead to inaccurate recordings not directly caused by intraoperative impairment of the motor cortex or the motor pathways. METHOD: This prospective study was conducted to quantify cortical brain shift during open cranial surgery and to assess its impact on electrode positioning in 31 procedures near the precentral gyrus. Three groups of different lesion volumes were distinguished. movement of the cortex between opening of the dura and completion of tumor removal as well as cortical electrode shifting were digitally measured and analyzed. FINDINGS: Cortical surface structures evidenced a significantly larger shift (up to 23.4 mm) in comparison to the electrode strips (up to 4.2 mm) in lesions with a volume of over 20 ml. Cortex shifting highly correlated with lesion volume, whereas strip electrode movement was almost unidirectional and did not differ significantly among the three groups. However, the way they were placed (completely on the cortex vs. partly underlying or overlapping the craniotomy borders) affected the magnitude of their intraoperative displacement. As a consequence, 3 of the 31 cases (9.3%) showed a significant change in the recorded motor responses due to intraoperative dislocation of the stimulating electrode. INTERPRETATION: Changes in the location of cerebral structures due to intraoperative brain shift may exert a marked influence on intraoperative neurophysiological monitoring if cortical strip electrodes are used. Therefore, long-term monitoring of the central region requires continuous checking of the position of stimulating electrodes and, if necessary, correction of their location.- - - - - - - - - - ranking = 0.722418642009keywords = record (Clic here for more details about this article) |
9/69. radiation leukoencephalopathy associated with moderate hydrocephalus: intracranial pressure monitoring and results of ventriculoperitoneal shunting.Delayed neurological sequelae of radiotherapy have several manifestations; leukoencephalopathy is one of the most common. Pathogenetic relationships between radiation leukoencephalopathy and other findings of diffuse radiation injury (brain atrophy and progressive ventriculomegaly) are not well defined. Moreover, no guidelines have been established for the treatment of hydrocephalus when associated with radiation leukoencephalopathy. Our study reports intracranial pressure (ICP) monitoring in two patients with radiation leukoencephalopathy with moderate hydrocephalus. High intraventricular mean pressure and high peaks were found, and marked improvement of clinical status after shunting was achieved. This study, although restricted to only two patients, shows that ventriculoperitoneal shunting insertion is useful in radiation-induced hydrocephalus, when ICP monitoring detects high mean pressure. A hypothesis is advanced concerning radiation-induced hydrocephalus with high ICP, emphasizing periventricular astrocytosis and its connections with cerebral compliance.- - - - - - - - - - ranking = 1keywords = relation (Clic here for more details about this article) |
10/69. Radiological response and histological changes in malignant astrocytic tumors after stereotactic radiosurgery.Stereotactic radiosurgery is an encouraging approach to deliver higher doses of radiation boost for malignant gliomas safely and precisely. The purpose of this study was to investigate the radiation response and histological changes of malignant astrocytic tumors after stereotactic linac radiosurgery (SLRS). We studied an autopsy case of recurrent glioblastoma multiforme (GBM) and two surgical cases with gross total removal of recurrent GBM and anaplastic astrocytoma transformed from fibrillary astrocytoma treated with SLRS. Destructive changes, such as the disappearance of viable cells, coagulation necrosis, and fibrinoid degeneration of vascular walls, were observed in the center of the target of SLRS, which showed histologically similar radiobiological reactions to well-known delayed central nervous system radiation necrosis caused by conventional radiotherapy. The region showing such radiation necrosis was within the area irradiated with approximately 15-20Gy or more by SLRS; however, dense viable tumor cells remained in the periphery that was irradiated with less than 15Gy. In a comparative immunohistochemical study of the tumors before and after SLRS, neither MIB-1 and p53 labeling indices nor immunoreactivity for GFAP represented any persistent tendencies. There were very few TUNEL-positive cells in either tumor before and after SLRS. These results showed that radiosurgery for malignant gliomas leads to earlier radiation necrosis than conventional radiation and that it is useful in eradicating tumor cells in the center of the target. However, some viable tumor cells may remain in the periphery irradiated with an insufficient dose for cell death and may be partly transformed in character by dna damage due to radiation. Proton magnetic resonance spectroscopy (MRS) was suggested to characterize the radiation response in radiosurgery tumor targets for correlation with histological findings.- - - - - - - - - - ranking = 1keywords = relation (Clic here for more details about this article) |
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