Use of Proton Magnetic Resonance Spectroscopy (Hl-MRS) of the Brain to Differentiation Postradiation Necrosis and Recurrency of Glioma in Patients Treated with brachytherapy Ir 192 HDR Method

摘要

Delayed radionecrosis is the term used in reference to demielinization changes of necrosis structures observed between 4 and 18 months after radiation therapy (2). Clinical abnormalities as increasing intracranial pressure and neurological deficits related to delayed radionecrosis are notified in about 40% patients who underwent brachytherapy and some cases must be operated on with removing of necrotic tissue (2,3,6). Before the introducing of modern imaging methods, delayed radionecrosis could only be diagnosed by histopathological examination. Computerised tomography with contrast infusion and magnetic resonance imaging did not differentiate radionecrosis and glioma recurrence because both situations have the following characteristic: irregular pathological mass with or without contrast enhancement and local oedema (1,7). Proton magnetic resonance spectroscopy ('H -MRS) of the brain appears to be new radiological method trying to solve this problem (4,5).