An experimental proton magnetic resonance spectroscopy analysis on early stage of acute focal cerebral ischemia

Abstract

Using different models of focal cerebral ischemia, the temporal and spatial rules of metabolism and energy changes in the post-ischemia brain tissue were measured by proton magnetic resonance spectroscopy (¹HMRS) to provide valuable information for judging the prognosis of acute focal cerebral ischemia and carrying out effective therapy. Nine healthy Sprague-Dawly rats (both sexes) were randomly divided into two groups: The rats in the group A (n=4) were occluded with self-thrombus for 1 h; The rats in the group B (n=5) were occluded with thread-emboli for 1 h. The¹H MRS at 30, 40, 50, 60 min respectively was examined and the metabolic changes of NAA, Cho and Lac in the regions of interest were semiquantitatively analyzed. The spectrum intregral calculus area ratio of NAA, Cho, Lac to Pcr+Cr was set as the criterion. The values of NAA · Cho in the regions of interest were declined gradually within 1 h after ischemia, especially, the ratio of Cho/(Pcr+Cr), NAA/(Pcr+Cr) at 60 min had significant difference with that at 50 min (P<0.05). The ratio of Lac/(Pcr+Cr) began to decrease at 40 min from initial increase of Lac in both A and B groups. MR proton spectrum analysis was a non-invasive, direct and comprehensive tool for the study of cellular metabolism and the status of the biochemical energy in acute ischemia stroke.

Keywords

acute focal cerebral ischemia / magnetic resonance proton spectrum

References

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