Changes in the apparent diffusion coefficient of water and T2 relaxation time in gerbil hippocampus after mild ischemia

Selective neuronal death of the hippocampal CAI area after mild ischemia is known as delayed neuronal death (DND). Progression of DND was evaluated us ing 7 T MRI in gerbils. in the CAI, the T2 relaxation time started to incre ase on day 3 and was significantly higher on day 4 than that of the control gerbils. However, the apparent diffusion coefficient of water (ADC) was si gnificantly lower on day I than in the control and continued to decline up to day 4. Changes in T2 coincided with loss of MAP2 immunoreactivity, while the ADC decrease preceded these changes. After I month, the ADC had return ed to within the normal range, while T2 had decreased to below the control level. These results suggest that MRI is useful for monitoring DND. NeuroRe port 11:3333-3336 (C) 2000 Lippincott Williams & Wilkins.