Objectives: The present study aimed to identify the brain regions involved in language function in subacute and chronic phase after stroke.
Methods: 40 patients with left hemisphere stroke with aphasia were included and divided into two groups (17 patients in subacute and 23 patients in chronic groups). The mean ages in subacute and chronic groups were 74.5 and 65.0 years respectively. The average duration from stroke onset in two groups were 43 and 2236 days respectively. Fractional anisotropy (FA) mapping using diffusion tensor imaging and language evaluation, including aphasia quotient, scores of spontaneous speech, comprehension, repetition and naming in the Korean version of Western Aphasia Battery were used for examinations. Linear regression analyses were conducted with the FA map as a dependent variable, each score of language evaluation as an independent variable, and patient age as a covariate.
Results: FA in the posterior limb of internal capsule and corpus callosum of the left hemisphere, bilateral frontal lobe were positively associated but FA in superior longitudinal fasciculus of the left hemisphere was negatively associated with aphasia quotient in acute group. FA in bilateral frontal lobe was positively associated with spontaneous speech and FA in superior temporal gyrus of the left hemisphere was positively associated with comprehension in acute group. FA in corpus callosum, frontal lobe of the left hemisphere were negatively associated with repetition in acute group. FA in left midbrain, superior longitudinal fasciculus and inferior parietal lobule of the right hemisphere were negatively associated with naming in acute group. However, FA in the splenium of corpus callosum of the right hemisphere was only negatively associated brain region with comprehension in chronic group (corrected p < 0.05).
Conclusions: Multiple bilateral brain regions positively and negatively influence the language function in subacute phase but not in chronic phase after stroke. |
