METABOLIC CHANGES IN ACUTE AND SUBACUTE CEREBRAL INFARCTIONS - FINDINGS AT PROTON MR SPECTROSCOPIC IMAGING

PURPOSE: To analyze the advantages of proton magnetic resonance (MR) spectroscopic imaging in the evaluation of acute and subacute cerebral infarcts. MATERIALS AND METHODS: Metabolite maps of choline-containing compounds, total creatine consisting of creatine and phosphocreatine, N-acetyl aspartate (NAA), and lactate were obtained in 23 patients with acute and subacute cerebral infarctions 1-35 days after onset of symptoms. Maps were obtained with a 1.5-T MR system with 32 x 32 phase-encoding steps. RESULTS: Distinct abnormal metabolite distributions could be detected in all lesions larger than 1 cm in diameter. In the center of infarcts with a diameter larger than the section thickness of 2 cm, NAA values decreased to 20% +/- 8 compared with contralateral brain as early as 1 day after onset of symptoms (P < .0001). Choline was reduced to 67% +/- 30 (not significant) and creatine to 51% +/- 22 (P = .0025). Large amounts of lactate were detected in all acute infarcts. Choline, creatine, and lactate values declined during the first 5 weeks after stroke. CONCLUSION: MR spectroscopic imaging allows visualization of metabolic changes in stroke with a reasonable spatial resolution.