A clinical magnetic resonance examination incorporating localized lH spectroscopy, localized 31P spectroscopy, and proton imaging, will be developed. This will be used to observe the physiologic and metabolic state of adult supratentorial gliomas in vivo. These tumors are rarely successfully excised completely, due to their location and/or size. A group of patients, with unresectable or minimally resected tumors, will be examined prior to radiation (or radiation plus chemotherapy), during its course and at its conclusion, and at the normal follow-up visit (1-6 months after the conclusion of radiation therapy). The spectral information will be mapped to the anatomical magnetic resonance images, in order to correlate variations in metabolism with regions of tumor and normal tissue. A smaller group of patients with completely resected tumors will be examined at 6-month intervals; spectral data from the excision region will be correlated with recurrence or continued freedom from tumor. The in vivo 31P observations will be made using chemical shift imaging (CSI). This technique will allow simultaneous observation of both the affected and normal hemispheres, with maximal resolution of 3-3.5 cm for 31P spectra. IH spectra will be collected by a stimulated-echo localization technique, possibly combined with 1-dimensional CSI. IH spectra will also be collected from both normal and pathological regions, with a spatial resolution of 2-3 cm. The data will be analyzed using an automatic software program developed at Fox Chase which allows for peak identification and quantification with automatic baseline estimation (PIQABLE). An automatic data analysis of this type is necessary to deal with the large number of spectra produced in these clinical observations. Spectroscopic data will be displayed as overlays on the proton image so that the full range of metabolic information provided by the spectral observations can be fully utilized in determining the differences between tumor and normal tissue, and the changes in gliomas in response to therapy.
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