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Query: UMLS:C0017638 (glioma)
 30,880 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Although several glioma models exist, systematic morphometrical studies on such experimental tumors are lacking. The purpose of this study was the quantitative assessment of how rat strains, cell lines, injection techniques and location affect tumors reproducibility and histopathological features. Glioma cells were implanted in 3 brain locations, with different injection techniques (free hand, stereotactic, water-tight device), variable volumes, cell concentrations and infusion rates. Tumors were developed from 2 rat glioma cell lines (9L and C6) in immunocompetent (Wistar and Fischer 344) and immunodeficient rats (New Zealand). Animals underwent daily neurological examination. At the scheduled time the tumors were macro and microscopically evaluated and a quantitative morphometrical analysis was performed. C6 gliomas appeared very infiltrative and irregularly shaped; 9L gliomas showed, by using the same injection technique, a grossly regular shape. Margins at the tumor-brain interface were macroscopically demarcated in the immunocompetent rats. In the nude rats, 9L tumors appeared microscopically more infiltrative, although regularly shaped, with a closer morphological resemblance to human gliomas. The implantation in the frontal area, anterior to the nucleus caudatus (3 mm anterior the coronal suture) gave reproducible tumor shape and size, no hydrocephalus and no early neurological deterioration. The use of a stereotactic technique or of a water-tight device, small volume (< 10 microl) of cell suspension, low infusion rate were useful to reduce morbidity and to improve data reproducibility. No difference in morbidity and mortality were observed in immunocompetent and immunodeficient rats. The 9L glioma model with stereotactic implantation constitutes a good option for reliable morphometrical evaluation of tumor growth. We propose a location for tumor implantation anterior to the nucleus caudatus. This produced the longest symptom-free survival.
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PMID:Morphometrical characterization of two glioma models in the brain of immunocompetent and immunodeficient rats. 1036 Apr 79

The term "chordoid glioma" was recently introduced to denote a circumscribed, apparently low-grade neoplasm arising in or preferentially involving the third ventricle of middle-aged women. We report biopsy and postmortem findings in a 60-year-old woman with symptoms of forgetfulness, headache, and lethargy. Neuroimaging showed a contrast-enhancing third ventricular mass with obstructive hydrocephalus. The tumor was subtotally resected. Microscopically, it consisted of clusters and strands of epithelioid cells in a mucoid matrix. Its margins were remarkably discrete and showed little tendency to infiltrate surrounding brain parenchyma. The majority of neoplastic cells were glial fibrillary acidic protein (GFAP) and vimentin positive, whereas S100 protein labeled only individual cells. Stains for epithelial membrane antigen (EMA) and cytokeratin were nonreactive. There was no evidence of neuroendocrine differentiation or expression of estrogen and progesteron receptors. Lymphoplasmacellular infiltrates were noted throughout the lesion and at the tumor-brain interface. The MIB-1 labeling index averaged 1.5%. At present, chordoid glioma is considered a glial neoplasm of uncertain histogenesis with distinct clinicopathologic features.
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PMID:Chordoid glioma of the third ventricle: confirmatory report of a new entity. 1037 85

Brainstem gliomas are a heterogeneous group of tumors whose prognosis and treatment depend not only on the histologic features but also on the location within the brainstem. Magnetic resonance imaging allows the recognition of a distinct type of brainstem glioma of the tectal region of the midbrain, leading to aqueductal compression and hydrocephalus. The radiologic appearance of these tumors is usually rather uniform, with a characteristic nonenhancing thickening of the tectal plate. Because of its protracted course, no further treatment is necessary beyond cerebrospinal fluid diversion and close clinicoradiologic follow-up. The authors report two children with tectal plate gliomas of unusual but strikingly similar appearance. They present a clinical picture suggestive of intracranial hypertension without localizing signs. Magnetic resonance images reveal hydrocephalus related to the presence of perfectly circular lesions, hypointense on T1 and hyperintense on T2, which could be mistaken for parasitic cysts or represent dilated rostral portions of the sylvian aqueduct. After the cerebrospinal fluid diversion procedures, no further treatment was given, with one of the patients being monitored for 10 years and the other for 8 months, without tumor progression. These patients demonstrate that tectal gliomas, despite sharing a good prognosis, may have various patterns of growth, leading to unusual radiologic appearances that may pose diagnostic difficulties.
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PMID:Globular glioma of the tectum. 1042 37

Intracranial metastasis without pulmonary involvement of Wilms' tumor is very rare, and most previously reported metastatic sites have been in the cerebral parenchyma. We experienced a rare case of metastasis of Wilms' tumor in the tectal plate without pulmonary involvement. A 3-month-old boy was admitted to our hospital due to hydrocephalus. After insertion of a ventriculoperitoneal shunt, there were no neurological deficits. Five months after the operation, a mass 5 cm in diameter extending from the tectal plate into the third ventricle was found. A mass 10 cm in diameter within the retroperitoneal space, which occupied the right kidney, was also found. Both tumors were resected and diagnosed histologically as Wilms' tumor. Despite every effort including chemotherapy and radiotherapy, the patient died at 14 months old. The majority of children with hydrocephalus showing thickening of the tectal plate would most likely have tectal glioma; however, this unusual case report reminds us that metastasis of Wilms' tumor can occur in the tectal plate causing hydrocephalus.
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PMID:Intracranial metastasis of Wilms' tumor involving the tectal plate without pulmonary involvement. Case report. 1049 60

Gliomas of the anterior visual pathways include the more commonly encountered benign tumors of children and the rare and highly aggressive malignant tumors of adults. Diagnostic biopsy is not required in most cases of childhood gliomas, especially those unassociated with visual loss or other neurologic symptoms, because the clinical and neuroimaging features are often sufficiently characteristic. Because of the infiltrative nature of these tumors, the neurosurgeon has little to offer symptomatic patients beyond debulking large exophytic masses and shunting if hydrocephalus is present.
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PMID:Gliomas of the anterior visual pathways. 1052 78

The authors report the unusual case of a 7-year-old child, one of the youngest reported to date, who developed repeated episodes of sympathetic hyperactivity after surgical resection of a midbrain glioma. These paroxysmal events were similar to previously described diencephalic seizures. However, there was no evidence of epileptogenic activity on electroencephalography, and radiologic imaging did not reveal hydrocephalus or intraparenchymal hemorrhage. In this report, clinical features are described of this patient, along with the novel use of clonidine--a sympathetic blocking agent--in his treatment, published reports are reviewed on diencephalic seizures, and steps are recommended in the treatment of a patient who presents in this manner. The authors believe that diencephalic seizures can present with a spectrum of autonomic features, and treatment should be tailored with the appropriate pharmacologic blockade.
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PMID:Sympathetic storms in a child with a midbrain glioma: a variant of diencephalic seizures. 1058 Aug 89

We report a case of optic glioma with bilateral optic atrophy. A 3-year-old girl presented with vomiting and left hemiparesis. She had hypothalamic dysfunction, right ptosis, right monocular nystagmus, left facial palsy, left hemiparesis, and left pes adductus. Neuroimaging studies showed obstructive hydrocephalus with a large suprasellar calcified tumor with a ring-like enhancement mimicking craniopharyngioma. Visual-evoked potentials showed delayed latency of N75 in the right occipital lead. The tumor, a pilocytic astrocytoma in the right optic tract and chiasma, was partially removed via a right frontotemporal craniotomy. The right optic nerve had shrunk to half the normal diameter and became twisted downwardly. Intracranial pressure (ICP) increased to 40 cm H2O. The fundus had bilateral optic atrophy without disc swelling. To our knowledge, this is the first report of a lamina/dot sign of the optic disc in a small child with a brain tumor and a normal neuroretinal fiber layer. These ocular findings may result from possible interruption of the axonal flow caused by the tumor and not increased ICP.
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PMID:Optic glioma with characteristic bilateral optic atrophy in a 3-year-old girl. 1070 32

Diencephalic gliomas may be grouped into 2 clinical categories. Optic pathway/hypothalamus gliomas (OPG) arise primarily from a slower-growing juvenile pilocytic astrocytoma, and thalamic gliomas arise primarily from a fibrillary astrocytoma which can become clinically and histologically more aggressive. Children with OPG have an excellent long-term prognosis with a 10-year survival of over 85%. The major therapeutic challenge for these patients is to maximize their quality of life by preserving visual and endocrine function while minimizing treatment-related morbidity. Treatment is often initiated at diagnosis in infants and toddlers who have a major visual impairment or the diencephalic syndrome. The judicious application of chemotherapy may serve to forestall the need for radiotherapy or surgery. Children with neurofibromatosis-1 (NF-1) usually have a more indolent course. Tumors may grow more slowly or occasionally regress spontaneously. However, over 90% of children with OPG without NF-1 will require some form of therapy. Patients with thalamic gliomas present with a shorter history, often with hydrocephalus. Surgical intervention is often required to relieve intracranial pressure and establish the histologic identity of the tumor. Over 75% of these tumors will become locally aggressive. Current multimodality therapy is relatively ineffective. The bithalamic variant behaves similarly to a pontine glioma.
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PMID:Initial management of children with hypothalamic and thalamic tumors and the modifying role of neurofibromatosis-1. 1086 64

The authors evaluated the impact of hydrocephalus on the clinical picture of children with visual pathway tumor (VPT) with or without neurofibromatosis (NF). Charts of children with VPT treated in the authors' center since 1985 were retrospectively reviewed, and those with hydrocephalus were selected and summarized. Thirty-five children with VPT were found, of whom 20 had NF. Hydrocephalus was found in 4 children with NF (20%) and in 5 without NF (33.3%). In 6 of the children, ventricular dilatation with signs of acute increased intracranial pressure already existed at the time of diagnosis and the hydrocephalus was shunted at this time. In the other 3 children, all with NF, the hydrocephalus resulted from slowly developing aqueductal stenosis, leading in 2 to severe visual acuity deterioration. The results suggest that in children with VPT and NF, hydrocephalus, and especially hydrocephalus resulting from aqueductal stenosis, is more frequent than in the general population of NF patients, and less frequent than in VPT patients without NF. The possibility of the indolent development of hydrocephalus should be borne in mind while following children with NF. The optic nerve, when already involved with a glioma, is more vulnerable to increased pressure. Thus, in children with VPT and NF, any ventricular dilatation should lead to a consideration of early shunting.
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PMID:Visual pathway tumors and hydrocephalus. 1098 66

Nasal encephaloceles can be divided into frontoethmoidal and basal encephaloceles. Both conditions are very rare, but frontoethmoidal encephaloceles show a relatively high incidence (1:5,000) in Southeast Asia. The pathogenesis of encephaloceles may be explained by a disturbance in separation of surface ectoderm (epithelial layer) and neurectoderm (nervous tissue) in the midline just after closure of the neural folds. It should be regarded as a 'late' neurulation defect taking place during the 4th gestational week. Apoptosis appears to be related to this separation process. Frontoethmoidal encephaloceles can be recognized as a facial mass covered with normal skin, while basal encephaloceles may cause nasal obstruction or symptoms related to herniation of basal structures. Diagnostic CT or MR imaging delineates the anatomy of the herniated mass. Therapy for frontoethmoidal encephaloceles consists in excision of the cele, watertight closure of the dural defect and reconstruction of the skull defect. Basal encephaloceles may harbour vital herniated structures which should be saved. Hydrocephalus should be dealt with first, followed by elective single-stage reconstructive surgery. The prognosis appears to be better for patients with frontoethmoidal encephaloceles than for patients with occipital or parietal encephaloceles, and it depends largely on the presence of additional congenital anomalies of the brain. The differential diagnosis of a nasal mass must include nasal glioma, dermoid cyst, and nasal polyp.
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PMID:Nasal encephaloceles. 1115 20


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