Mean Value Change of Magnetic Resonance Imaging Apparent Diffusion Coefficient in White Matter Development of Neonates and Children

Abstract

Objective To study mean value change of magnetic resonance imaging (MRI) apparent diffusion coefficient (ADC) in white matter development of neonates, children and teenagers. Methods From December 2006 to January 2008, 100 normal neonates and children were included into study(group A). They were classified into six groups according to their age: A1 group (n=7, less than 1 month), A2 group (n=18, 1 month to 1 year old), A3 group (n=6, 1 to 2 years old), A4 group (n=23, 2 to 5 years old), A5 group (n=24, 5 to 10 years old), and A6 group (n=22, 10 to 15 years old). Another 14 children aged from 15 to 20 years old were selected into group B. Informed consent was obtained from all participants. Both of two groups were examined by MR scanner (Siemens Sonata 3.0 T) on brain with diffusion-weighted imaging (DWI), and the mean value of the apparent diffusion coefficient was acquired by measuring six different regions of interest (ROI) in periventricular white matter in each age group. Results ①There was an obvious negative correlation between age and mean value of the apparent diffusion coefficient of white matter of parietal lobe in neonates and children. The negative correlation was strong before 2-year-old, while it became mild after 2-year-old. ② Gender was not a strong factor in the mean value of the apparent diffusion coefficient change. Mean value of the apparent diffusion coefficient of periventricular white matter in neonates and children with same age and different gender were compared. Only group A4 (2 to 5 years old) showed a significant difference (P=0.043). There had no significant differences in other groups or all the testers(P>0.05). ③ The left mean value of the apparent diffusion coefficient in 114 normal neonates, children and teenagers was 1039.319×10-5mm2/s, and the right mean value was 1026.295×10-5 mm2/s. There was no significant difference between both sides(t=0.613, P>0.05). Conclusion The mean value of apparent diffusion coefficient could be regarded as a quantification index to reveal brain white matter changes during development. The mean value of the apparent diffusion coefficient change was previous to routine magnetic resonance imaging change. Key words: magnetic resonance imaging(MRI); apparent diffusion coefficient (ADC); brain; neonate; child