Magnetic Resonance Spectroscopy And Perfusion Study In Early Radiation-induced Brain Injury

Objective:To observe the change of the metabolic derangements and miccirculation of the brain radiation injury following radiotherapy for nasopharyngeal carcinoma through magnetic resonance spectroscopy(~1HMRS) and perfusion(MRP);to elucidate the pathogensis and provide basic theory for early detection and early therapy of early radiation-induced brain injury. Material and Methods:5 healthy subjects and 19 nasophary cancer (NPC) before radiotherapy were one group, and 52 NPC after radiotherapy were other group .which Proton MR spectroscopy was used to ascertain the amount of the N-acetylaspartate(NAA),choline(Cho) ,creatine(Cr).6 healthy subjects and 7 NPC before radiotherapy were one group, and 16 NPC after radiotherapy were other group, which MR perfusion was used to get the value of regional cerebral blood volum (rCBV) and regional cerebral blood flow (rCBF) in temple lober.The peak values of NAA, Cho, Cr on MRS and rCBV, rCBF on MRP before and after radiotherapy were measured,then the results were compared and statistically analyzed.52 nasopharyngeal carcinoma after radiotherapy were divided into three groups according time.The peak values of NAA , Cho, Cr on MRS were measured,then the results were compared and statistically analyzed. Results:A significant decrease of NAA/Cr and significant increase of Cho/Cr, Cho/NAA occurred at the early stage of brain injury.After 3 months,The peak values of NAA, Cho, Cr can begin to back to normal.A significant decrease of rCBV occurred on the nasopharyngeal carcinoma after radiotherapy .