Longitudinal changes in white matter following ischemic stroke: a three-year follow-up study.

Information on longitudinal changes in white matter after stroke is limited. The aim of the present study was to quantitatively investigate longitudinal changes in the microstructural integrity of non-lesioned white matter at 1-3 years following ischemic stroke. In a sample of 80 ischemic stroke patients, we obtained diffusion tensor imaging (DTI) measures of fractional anisotropy (FA), an apparent measure of white matter integrity, in radiologically normal-appearing white matter at baseline and 3 years of follow-up. Mixed model regression analysis results showed a significant improvement in FA from baseline during the first 2 years of follow-up that stabilized by the third year of follow-up. These results demonstrate a long-term improvement in apparent white matter integrity following ischemic stroke that continues, at least, into the second year following the insult.