Unusual mode of spread and presentation of meningioma: a case report. (33/1193)

Although rare, extracranial extension of a meningioma has been well documented. An interesting natural history of neglected meningioma with skull vault hyperostosis and predominantly extracranial extension is described. Following surgical resection of the highly vascular meningioma, the patient developed fatal coagulopathy.  (+info)

The effects of exogenous growth factors on matrix metalloproteinase secretion by human brain tumour cells. (34/1193)

Matrix metalloproteinases (MMPs) are a growing family of zinc-dependent endopeptidases that are capable of degrading various components of the extracellular matrix. These enzymes have been implicated in a variety of physiological and pathological conditions including embryogenesis and tumour invasion. The synthesis of many MMPs is thought to be regulated by growth factors, cytokines and hormones. In this study, we investigated the effects of five exogenous growth factors known to be expressed by gliomas [epidermal growth factor (EGF), basic growth factor (bFGF), transforming growth factor beta (TGF-beta1,2) and vascular endothelial growth factor (VEGF)].on MMP-2 and MMP-9 expression in an ependymoma, two grade III astrocytomas, a grade III oligoastrocytoma and a benign meningioma. Zymogram analysis revealed that the effects of the growth factors depended upon the cell lines used in the study. Growth factors generally up-regulated MMP-2 and MMP-9 expression in the gliomas but were least effective in the meningioma; the effect being most prominent with TGF-beta1 and TGF-beta2 in all the cell lines. It is hypothesized that paracrine growth factor interplay may be crucial in the regulation of MMP expression by glioma invasion of the normal brain.  (+info)

MR imaging features of clear-cell meningioma with diffuse leptomeningeal seeding. (35/1193)

Clear-cell meningioma is a rare disease entity showing a more aggressive nature, clinically, than those of other subtypes of meningioma. It occurs in younger persons and commonly in the spinal canal. The recurrence rate has been reported to be as high as 60%. We present a case of clear-cell meningioma in a 17-year-old man in whom initial MR imaging showed localized leptomeningeal enhancement that had progressed into the entire subarachnoid space after surgical resection of the primary tumor.  (+info)

An iatrogenic epidemic of benign meningioma. (36/1193)

Head irradiation, the acceptable mode of treatment for tinea capitis in the past, is recognized today as a causative factor for meningioma. This treatment was applied en mass to immigrants coming to Israel from North Africa and the Middle East during the 1950s. In order to estimate the effect of the differential radiation treatment on the rates of meningioma in the total population, the authors assessed time trends of this disease in Israel over the past 40 years by main ethnic origin. Cohort analysis shows a marked incidence rise in the North African-born cohorts born in 1940-1954 starting from the 1980s. A similar pattern is seen in the Middle Eastern born, although the increase is not as sharp. In consequence, there is a crossover of the interethnic incidence curves in the 1940-1949 cohort. Comparison of the relative risk between 1940-1954 cohorts that comprised most of the irradiated with 1930-1939 cohorts, who were largely free of the radiation, shows that the North African born have the largest relative risk of 4.62, followed by the Middle Eastern born, with a relative risk of 1.95, while the European-American born have a relative risk close to 1. The differences between the three areas of birth are statistically significant. The data illustrate the potential risk of administering highly potent therapy for an essentially benign disease that led, in turn, to a drastic change in the national meningioma pattern.  (+info)

Efficacy of trisacryl gelatin microspheres versus polyvinyl alcohol particles in the preoperative embolization of meningiomas. (37/1193)

BACKGROUND AND PURPOSE: Trisacryl gelatin microspheres are a new, commercially available nonabsorbable embolic agent. The purpose of this study was to evaluate their efficacy in the preoperative embolization of meningiomas as compared with polyvinyl alcohol (PVA) particles of various sizes. METHODS: In 30 consecutive patients, trisacryl gelatin microspheres (150-300 microm) were used for the preoperative superselective embolization of meningiomas (group 1). Thirty other consecutive patients had embolization with PVA particles of 45 to 150 microm (n = 15, group 2) and of 150 to 250 microm (n = 15, group 3). Extent of devascularization, intraoperative blood loss, blood transfusion, and hemostasis at the time of surgery were recorded for every patient. The inflammatory reaction, the extent of necrotic areas, and the most distal intravascular location of the embolic agent (arterial, arteriolar, precapillary, capillary) were recorded. RESULTS: There was no significant difference in the extent of angiographic devascularization among the groups. Intraoperative blood loss differed significantly between groups 1 and 2 and groups 1 and 3, but not between groups 2 and 3. The trisacryl gelatin microspheres were located more distally in tumor vessels than were the PVA particles of either size. The extent of intratumoral necrosis was not significantly different between the two embolic agents. In all groups there was a mild inflammatory tissue reaction in the vicinity of the embolic agent. CONCLUSION: Trisacryl gelatin microspheres may be effective in the preoperative embolization of meningiomas, producing significantly less blood loss at surgery than seen with PVA particles of either size, possibly because of the significantly more distal vascular penetration of the microspheres.  (+info)

Sphenoid wing meningioma--an unusual cause of duro-optic calcification. (38/1193)

Sphenoid ridge is the third commonest site of intracranial meningiomas. Although sphenoid ridge meningiomas often involve the optic canal, calcification along the optic nerve has not been reported with these tumors. We describe CT features of a calcified optic nerve in a patient with a calcified sphenoid ridge meningioma.  (+info)

Pituitary adenoma and parasagittal meningioma: an unusual association. (39/1193)

Simultaneous detection of an intracranial meningioma with a pituitary tumour prior to radiotherapy is an extremely uncommon occurrence. Authors have managed an elderly acromegalic lady with an acidophilic pituitary adenoma, who also harboured an asymptomatic anterior third parasagittal meningioma. There were no features of neurofibromatosis. Both tumours were concurrently excised.  (+info)

Posterior fossa craniotomy. Technical report. (40/1193)

The use of craniotomy to approach supratentorial lesions is quite well established in the literature. The use of craniotomy for posterior fossa approaches, however, is not well described. The aim of this article is to describe the technical aspects of this approach and to delineate the important landmarks. In our cases, posterior fossa craniotomies have been utilized for treat different pathologies. Additionally, the technique has not added any additional risk, and the cosmetic results have been excellent.  (+info)