Objective To explore the connection of fibers among functional language areas in the normals and the patients with subcortical aphasia using diffusion tensor imaging (DTI) and diffusion tensor fiber tractography (DT-FT). Methods From June, 2016 to May, 2017, 20 healthy subjects and three stroke patients whose lesion located in subcortical structures were included. There were two patients with Broca's aphasia and one with conductive aphasia from the Western Aphasia Battery. They were scanned with DTI and DT-FT, while the fractional anisotropy (FA) of functional language areas and contralateral mirror areas were measured, and the relevant fibers were observed. Results The structures of functional language areas were complicated and extensively connected with other cortex and subcortical structures in healthy subjects, with few differences among individuals. FA was lower in the functional language areas and arcuate fasciculus than in the mirror regions in patients, and the fibers were damaged, distorted or shifted.Conclusion Structures related to language are very complicated, which involve cortex, lots of white matter tracts, subcortical structure and others. The damage, transformation or transposition of fibers in functional language areas may be the mechanism of subcortical aphasia.
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