Early diagnosis of cognitive dysfunction based on anisotropic diffusion of the cerebral white matter

<p>[Purpose] We use MR diffusion tensor imaging (DTI) to measure the fractional anisotropy(FA), which is an index of anisotropic diffusion in the cerebral white matter tracts, and to evaluate subjective cognitive impairment (SCI) and mild cognitive impairment (MCI).This study revealed the possibility of diagnosing cognitive dysfunction at an early stage.</p><p>[Cases and Methods] These cases were patients who were found to have decreased memory ability during a forgetfulness outpatient visit. Classification was based on the clinical dementia scale CDR. DTI was taken in all cases, and the FA value was measured. They were measured by setting regions of interest at five locations in the cerebral white matter fiber tracts (left and right uncinate fasciculus, left and right posterior cingulate fasciculus, and splenium of the corpus callosum) on DTI color map.</p><p>[Results] This time, 19 patients were assigned to SCI group, 45 patients to MCI group, 37 patients to AD group, and 14 patients to healthy group as controls. Compared with healthy group, there was a significant decrease in the FA value of the left uncinate fasciculus in SCI group, and in the right uncinate fasciculus in MCI group.</p><p>[Conclusion] In SCI and MCI groups, we observed a decrease in the FA value of uncinate fasciculus, that is, structural changes in nerve fibers in the cerebral white matter, compared to healthy group. By quantifying changes in the cerebral white matter by anisotropic diffusion of DTI, it has been suggested that the FA value is an indicator that can quantitatively and objectively evaluate cognitive dysfunction from an early stage, similar to changes in the cerebral cortex.</p>