Diffusion tensor imaging in infants with basal ganglia-thalamic lesions

We performed diffusion tensor imaging in two infants with neonatal hypoxic-ischemic encephalopathy. MRI revealed basal ganglia-thalamic lesions in both patients during the neonatal period. Patient 1 had severe neurological sequelae, whereas patient 2 achieved normal development. Conventional MRI at 12 months of age showed abnormal high-intensity areas in bilateral basal ganglia and thalami in patient 1, whereas no abnormal intensities were recognized in patient 2. Diffusion tensor tractography demonstrated poor depiction of white matter tracts above the level of centrum semiovale in patient 1. Region of interest analysis showed that fractional anisotropy of white matter of centrum semiovale and deep white matter was markedly reduced in patient 1 compared with patient 2, although apparent diffusion coefficient was not largely different between them. Our study suggested that abnormalities of diffusion property will be more widely present than those of conventional MRI. Diffusion tensor imaging will be useful to detect white matter abnormalities in normal-appearing white matter on conventional MRI.