Diffusion alterations associated with Parkinson's disease symptomatology: A review of the literature. (December 2016)

• Record Type: Journal Article
• Authors: Hall, Julie M.; Ehgoetz Martens, Kaylena A.; Walton, Courtney C.; O'Callaghan, Claire; Keller, Peter E.; Lewis, Simon J.G.; Moustafa, Ahmed A.
• Is Part Of: Parkinsonism & related disorders. Volume 33(2016)
• Page Start: 12
• Page End: 26
• Publication Date: 2016-12
• Subjects: Parkinson's disease -- White matter tracts -- Diffusion tensor imaging -- Heterogeneity; PD Parkinson's disease -- DTI diffusion tensor imaging -- FA fractional anisotropy -- MD mean diffusivity -- TBSS tract-based spatial statistics -- ROI region of interest -- SN substantia nigra -- SLF superior longitudinal fasciculus -- IF-OF inferior fronto-occipital fasciculus -- PPN pedunculopontine nucleus -- PIGD postural instability and gait disorder -- FOG freezing of gait -- MCI mild cognitive impairment -- VH visual hallucinations -- RBD REM sleep behaviour disorder; Parkinson's disease -- Periodicals; Movement disorders -- Periodicals; Movement Disorders -- Periodicals; Nerve Degeneration -- Periodicals; Nervous System Diseases -- Periodicals; Parkinson Disease -- Periodicals; Tremor -- Periodicals; Parkinson, Maladie de -- Périodiques; Parkinson's disease; 616.833
• DOI: 10.1016/j.parkreldis.2016.09.026
• Languages: English
• ISSNs: 1353-8020

Abstract

Abstract: Parkinson's disease (PD) is a heterogeneous neurological disorder with a variety of motor and non-motor symptoms. The underlying mechanisms of these symptoms are not fully understood. An increased interest in structural connectivity analyses using diffusion tensor imaging (DTI) in PD has led to an expansion of our understanding of the impact of abnormalities in diffusivity on phenotype. This review outlines the contribution of these abnormalities to symptoms of PD including bradykinesia, tremor and non-tremor phenotypes, freezing of gait, cognitive impairment, mood, sleep disturbances, visual hallucinations and olfactory dysfunction. Studies have shown that impairments in cognitive functioning are related to diffusion abnormalities in frontal and parietal regions, as well as in the corpus callosum and major fibres connecting midbrain and subcortical structures with the neocortex. However, the impact of diffusion alterations on motor, mood and other symptoms of PD are less well understood. The findings presented here highlight the challenges faced and the potential areas of future research avenues where DTI may be beneficial. Larger cohort studies and standardized imaging protocols are required to investigate current promising preliminary findings. Highlights: Examines diffusivity changes in white and grey matter in PD. Widespread diffusivity abnormalities correlate to a variety of PD symptoms. DTI analyses can improve our understanding of PD heterogeneity. Future studies are needed to address inconsistencies in the literature.