LONGITUDINAL CHANGES IN PROTON MAGNETIC-RESONANCE SPECTROSCOPY IN CEREBRAL INFARCTION

Background and Purpose: Proton magnetic resonance spectroscopy has rev ealed changes in lactate and N-acetyl-aspartate in acute cerebral infa rction. However, the details of these drastic changes and subsequent c hronic changes have not been clarified. The purpose of this study was to disclose longitudinal changes in spectra seen in proton magnetic re sonance spectroscopy. Methods: Six patients with completed cerebral in farction were examined longitudinally with localized proton magnetic r esonance spectroscopy. Results: (1) In the acute stage (within 2 days after onset), two drastic changes were observed: N-acetyl-aspartate de creased rapidly and severely within 2 days after onset, and lactate in creased immediately and reached a high level in the acute stage after onset. (2) In the chronic stage (more than 1 month after onset), two f eatures were observed: lactate, which had increased in the acute stage , remained high for more than 1 month, and other signals such as those of N-acetyl-aspartate, choline, and phosphocreatine/creatine decrease d dramatically. Conclusions: These results suggest that N-acetyl-aspar tate and lactate as revealed by proton magnetic resonance spectroscopy can be useful indicators of the ischemic damage to the brain in clini cal cases of cerebral infarction.