| Gliomas are the most frequent tumor in central nervous system of human being. Their treatments recently have had some progress in neurosurgery, radiotherapy, chemotherapy, but their total curative effect and prognosis are still worse. They have been the firstly most tumor diseases of nervous system threatened human. Their determination of prognosis and selection of treatment methods mostly are dependent on their malignant grade. But it is important characteristic in histology that glioma has high tissue heterogeneity. Histopathology may exactly diagnose the malignant grade of cerebral gliomas, but the diagnosis often is affected by sample errs and is postoperative, and it is badly in need of detective indexes which clinically can help pathology to diagnose the malignant grade of cerebral gliomas exactly, and they are postoperative as well as preoperative, for they can guide doctors to treat the diseases correctly and to determinate their prognosis. The studies recently indicate that tumor angiogenesis is required for tumor growth and metastasis and is controlled by oncogene. Evidence from recent in vitro studies indicates that reactivation of telomerase, the enzyme that synthesizes the telomere ends of chromosomes, is a crucial event in the unlimited clonal expansion of endothelial cells that precedes the neoplastic conversion of these cells. It is known that high - grade gliomas express telomerase and that, in these neoplasms,proliferating endothelial cells may undergo transformational changes with development of sarcomatous components within the primitive tumor. Angiogenesis is adjusted and controlled by the angiogenic factors and inhibitive factors which are released by tumor cells, endothelial cells and macrophage. The studies have showed that the angiogenic factors chiefly include vascular endothelial growth factor (VEGF) and fibroblast growth factor ( FGF). The expression of VEGF has been found in different grade of glioma, but the expression level is different. It does not be expressed or is lowly expressed in normal glial cells, lowly expressed in low grade of glioma and highly expressed in high grade of glioma (glioblastoma). A statistically significant correlation has been demonstrated between prognosis and the microvessel density (MVD) (a measure of tumor angiogenesis) of solid tumors. But both measuration to VEGF and measuration of MVD are postoperative and similar with pathology diagnosis. The development of medical image equipments and relative technique recently make accuration of it raised to determinate the location and nature (benign or malignant) of cerebral tumor. The methods of medical imaging can yet show the state and degree of perfusion in organ or tissue, perfusion imaging, can yet show tumor angiogenesis. Perfusion imaging may be additional with normal dissection imaging each other, and more information about diagnosis or differential diagnosis is offered before operation.In this study, we performed the examinations of routine magnetic resonance imaging ( MRI) and dynamic magnetic susceptibility enhancement perfusion imaging, i. e. , perfusion weighted imaging ( PWI) for 38 patients who had been diagnosed to suffer with cerebral gliomas before operation to detect relative cerebral blood volume (rCBV) of brain tumor, and their pathological samples were immuno-histochemistrily stained to detect expression rate of VEGF and intratu-mor MVD, to compare them into high grade group with low grade group and to analyze their relativity. The aims of this study were to find some indexes to detect the angiogenesis in cerebral gliomas, which especially help to determinate glioma grade before operation, for diagnosing their grades and determinating prognosis.Materials and methodsMR examinations were performed preoperatively in 38 patients with suspected cerebral gliomas, and all cases were proved by operation and pathology. The procedures of MR examinations were plain MR scan, PWI and routine contrast - enhanced MR scan. The pulse sequence of PWI was single shot GRE - EPI - T2 * W...
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