The magnetic resonance imaging measurement of the hippocampal formation volume of normal Chinese adults.

The objective of this study was to measure the normal hippocampal formation of the adults in China and to provide data for the prevention and diagnoses of the related diseases. 3D-fSPGR sequence scanning was used in 68 cases of healthy adult brain to gain the image between lateral border of bilateral fourth ventricle and vitreous body. The image then was divided into 10 equal parts in the sagittal plane. We can trace the area of the hippocampal formation in each part and the data gained was analyzed by SPSS to calculate the volume. The calibrated normal adult average hippocampal formation volume on the right was 2649.92-2903.17 mm(3) while on the left was 2579.42-2803.27 mm(3). The male right average hippocampal formation volume was 2601.84-2986.44 mm(3) and the left was 2526.32-2886.94 mm(3). The female right average hippocampal formation volume was 2531.88-2819.06 mm(3) and the left was 2579.42-2803.27 mm(3). There was no obvious difference in various gender and age groups (P > 0.05), but there was a significant difference between bilateral hippocampal formation volume in middle-aged and elderly male group whether calibrated (t = 2.892, P< 0.05) or not (t = 2.924, P < 0.05). We can conclude that the hippocampal formation volume of normal Han adults has no relation to gender and age except that the bilateral fourth ventricle volume of middle-aged and elderly men were evidently different from each other.