Multivoxel proton magnetic resonance spectroscopy in heat stroke

AIM: To assess the role of proton MR spectroscopy (MRS) in the detection of changes in metabolite levels of the cerebellum after heat stroke (HS). MATERIALS AND METHODS: The study group consisted of eight patients after HS, with a Glasgow Coma Scale (GCS) score of 3-9. The MR studies were performed with a 1.5 T system. MR spectra were recorded from a normal-appearing cerebellum region. Spectra from patients were compared with a control group including seven age-matched healthy volunteers recorded with the same techniques. Metabolites ratios including N-acetyl aspartate/creatine (NAA/Cr), N-acetyl aspartate/creatine2 (NAA/Cr2), choline/creatine (Cho/Cr), choline/creatine2 (Cho/Cr2), and N-acetyl aspartate/choline (NAA/Cho) were calculated and the differences between the two groups were evaluated using the Mann Whitney U-test. Pearson correlation analysis was used to analyse the relationship between NAA/Cr ratios and GCS scores for eight patients after HS. RESULTS: In the cerebellum of the patients after HS, NAA/Cr ratios were found to be significantly decreased compared to normal controls (p = 0.004) and Cho/Cr ratios were found to be decreased compared to normal controls (p = 0.032). Significant positive correlation was found between NAA/Cr ratios and GCS scores for eight patients after HS (r = 0.748, p = 0.033). CONCLUSIONS: Metabolite abnormalities were seen in normal-appearing cerebellum structures in patients after HS. Proton MRS is a useful tool for evaluating major changes in metabolite levels of the cerebellum after HS and the severity of the disease can be effectively evaluated by NAA/Cr ratios. (C) 2014 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.