Figure 1

(a) T₂-weighted proton image showing diffuse injury to the cerebral cortex following CCI injury. The ipsilateral and contralateral regions of interest (ROIs) are shown by red and green outlines, respectively. (b) and (c) Fluoro-Jade B staining of the ipsilateral and contralateral hemispheres, respectively, 30 days after CCI injury. Fenestrated, dead tissue is outlined in orange and dead or dying cells are outlined in green. (d) Two typical hyperpolarized ¹³C MRSI spectra taken from ROIs on either side of the brain in an injured animal, showing an increase in lactate (lac) and decrease in bicarbonate (bic) intensity on the ipsilateral side. Pyruvate (pyr) and pyruvate hydrate (pyh) are also shown. (e) and (f) Maps of ¹³C signal for pyruvate (pyr), lactate (lac), bicarbonate (bic), and the bicarbonate-to-lactate ratio (bic/lac) in the rat brain of a control animal and an animal injured with a 2.0 mm deep controlled cortical impact (CCI), respectively. Significant differences in lac, bic, and bic/lac are evident in the brain surrounding the site of injury versus the rest of the brain. The control animal shows a more symmetric signal distribution.