Constrained spherical deconvolution -based tractography of major language tracts reveals post-stroke bilateral white matter changes correlated to aphasia

•CSD-tractography revealed bilateral WM changes, suggestive of degenerative process in post stroke aphasic patients.•Injury of the left AF and left ILF correlate with comprehension impairment.•White matter micro-structural changes of the right AF correlate with repetition impairment.•Diffusion measures can act as biomarkers for detection of post stroke white matter changes.