Levodopa responsiveness in Parkinson's disease patients and white matter alterations in diffusion tensor imaging: a cross-sectional tract-based spatial statistics study.

This study aimed to investigate the relationship between levodopa responsiveness and white matter alterations in Parkinson's disease patients using diffusion tensor imaging (DTI). Twenty-six recruited Parkinson's disease patients were evaluated using the Mini-Mental State Examination, Hoehn and Yahr scale (HY cingulum; left corona radiata; left internal capsule; left middle frontal gyrus; left superior longitudinal fasciculus and right somatosensory cortex. Mean diffusivity and radial diffusivity were increased in wide-ranging areas in the nonresponsive group. No difference was observed in axial diffusivity. White matter alterations in the abovementioned areas may affect the function of the dopaminergic network and thus may be associated with the levodopa response in Parkinson's disease patients. Further studies are needed to analyze the specific mechanism and pathological changes underlying these effects.