The clinical application of the arcuate fasciculus for stroke patients with aphasia: A diffusion tensor tractography study

Little is known about the clinical usefulness of diffusion tensor tractography (DTT) for the arcuate fasciculus (AF) in stroke patients with aphasia. Using DTT, we attempted to investigate the clinical usefulness of the AF in patients with aphasia. Five stroke patients and 7 age- and sex-matched normal subjects were recruited for this study. We recruited stroke patients with language dysfunction who had lesions in the left corona radiata and basal ganglia level. DTT for the AF was reconstructed using DTI-studio software. Korean-Western Aphasia Battery (K-WAB) was used for measurement of language function. Patient 1, who showed mild dysarthria, revealed a normal left AF in terms of integrity and DTT parameters. In patient 2, with conduction aphasia, the left AF showed partial injury; however, the integrity of the left AF was spared. Patients 3 and 4, who had no brain lesions at Broca's area on conventional brain MRI, showed disruptions of the left AF over the stroke lesions after originating from Wernicke's area and they presented with Broca's aphasia. Patient 5 revealed global aphasia on K-WAB and the left AF was not reconstructed due to severe injury and Wallerian degeneration. We found that DTT for the AF could provide useful information on the presence or severity of injury of the AF, which could not be detected on conventional brain MRI in stoke patients. In addition, it could be helpful in classification of the aphasia type of stroke patients.