Idiopathic Parkinson Disease

Razek, Ahmed Abdel Khalek Abdel; Elmongy, Azza; Hazem, Maha; Zakareyia, Shirin; Gabr, Wael

doi:10.1016/j.acra.2010.08.023

Cited by 21 publications

(10 citation statements)

References 25 publications

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“…These changes observed in gray matter are highly consistent with the results of previous studies that investigated the effects of intervention on MD (Abe et al 2014 ; Razek et al 2011 ; Sagi et al 2012 ). Furthermore, two of these studies reported an increase in MD in the gray matter (Abe et al 2014 ; Razek et al 2011 ). As described above, changes in synapse or synaptic vesicles, astrocytes, dendritic sprouting, and angiogenesis have been demonstrated or considered as the causes of these changes in MD.…”

Section: Discussionsupporting

confidence: 91%

“…MDDS has been shown to be more accurate in dissociating the pathology of dopaminergic systems than PET measures of dopamine receptor binding (Seppi et al 2004 ). It can also detect the neural plasticity caused by medication with dopamine agonists to manage this pathology (Razek et al 2011 ). MDDS was also robustly associated with the motivational state and novelty seeking (Takeuchi and Kawashima 2013 ) which are strongly associated with the function of the dopaminergic system (Bódi et al 2009 ; Kaasinen et al 2004 ; Kaplan and Oudeyer 2007 ; Schinka et al 2002 ; Suhara et al 2001 ; Tomer and Aharon-Peretz 2004 ).…”

Section: Introductionmentioning

confidence: 99%

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Working memory training impacts the mean diffusivity in the dopaminergic system

et al. 2014

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Dopaminergic transmission plays a critical role in working memory (WM). Mean diffusivity (MD) is a sensitive and unique neuroimaging tool for detecting microstructural differences particularly in the areas of the dopaminergic system. Despite previous investigation of the effects of WM training (WMT) on dopamine receptor binding potentials, the effects of WMT on MD remain unknown. In this study, we investigated these effects in young adult subjects who either underwent WMT or received no intervention for 4 weeks. Before and after the intervention or no-intervention periods, subjects underwent scanning sessions in diffusion-weighted imaging to measure MD. Compared with no intervention, WMT resulted in an increase in MD in the bilateral caudate, right putamen, left dorsolateral prefrontal cortex (DLPFC), right anterior cingulate cortex (ACC), right substantia nigra, and ventral tegmental area. Furthermore, the increase in performance on WMT tasks was significantly positively correlated with the mean increase in MD in the clusters of the left DLPFC and of the right ACC. These results suggest that WMT caused microstructural changes in the regions of the dopaminergic system in a way that is usually interpreted as a reduction in neural components.

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Section: Discussionsupporting

confidence: 91%

Section: Introductionmentioning

confidence: 99%

Working memory training impacts the mean diffusivity in the dopaminergic system

et al. 2014

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“…37 Further, an intervention study of Parkinson's disease revealed that administration of the dopamine agonist L-dopa led to increased MD in regions of the dopaminergic system. 14 Therefore, a greater amount of VGP and concomitant increase in dopamine release are associated with later MD changes in the dopaminergic system, akin to the effects of substances that release dopamine. The MD of these areas is associated with traits with negative affect, whereas excessive VGP is associated with emptiness or depressive tendencies when not playing videogames.…”

Section: Discussionmentioning

confidence: 99%

“…11, 12 In particular, MD in the dopaminergic system has been shown to be quite sensitive to pathological, pharmacological and cognitive differences or changes related to dopamine. 12, 13, 14, 15 On the other hand, FA is known to be relatively more strongly associated with microstructural properties related to brain connectivity and sensitive to increases in axonal membrane thickness, diameter and/or the amount of parallel organization of the axons and can also reflect the process of neural plasticity. 10, 16 We, therefore, utilized these measures in this study.…”

Section: Introductionmentioning

confidence: 99%

Impact of videogame play on the brain’s microstructural properties: cross-sectional and longitudinal analyses

et al. 2016

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Videogame play (VGP) has been associated with numerous preferred and non-preferred effects. However, the effects of VGP on the development of microstructural properties in children, particularly those associated with negative psychological consequences of VGP, have not been identified to date. The purpose of this study was to investigate this issue through cross-sectional and longitudinal prospective analyses. In the present study of humans, we used the diffusion tensor imaging mean diffusivity (MD) measurement to measure microstructural properties and examined cross-sectional correlations with the amount of VGP in 114 boys and 126 girls. We also assessed correlations between the amount of VGP and longitudinal changes in MD that developed after 3.0±0.3 (s.d.) years in 95 boys and 94 girls. After correcting for confounding factors, we found that the amount of VGP was associated with increased MD in the left middle, inferior and orbital frontal cortex; left pallidum; left putamen; left hippocampus; left caudate; right putamen; right insula; and thalamus in both cross-sectional and longitudinal analyses. Regardless of intelligence quotient type, higher MD in the areas of the left thalamus, left hippocampus, left putamen, left insula and left Heschl gyrus was associated with lower intelligence. We also confirmed an association between the amount of VGP and decreased verbal intelligence in both cross-sectional and longitudinal analyses. In conclusion, increased VGP is directly or indirectly associated with delayed development of the microstructure in extensive brain regions and verbal intelligence.

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“…Previous study results are conflicting whether or not levadopa treatment would be of influence on changes in diffusivity of different brain structures. One study reported significant differences in putaminal ADC values between PD patients on levodopa treatment and matched untreated patients [ 52 ], and they suggested that these differences could be attributed to the use of levodopa. However, other studies found no effect of levodopa treatment on FA or ADC values [ 53 , 54 ].…”

Section: Discussionmentioning

confidence: 99%

Conventional 3T brain MRI and diffusion tensor imaging in the diagnostic workup of early stage parkinsonism

et al. 2015

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IntroductionThe aim of this study is to evaluate whether the diagnostic accuracy of 3 T brain MRI is improved by region of interest (ROI) measures of diffusion tensor imaging (DTI), to differentiate between neurodegenerative atypical parkinsonism (AP) and Parkinson’s disease (PD) in early stage parkinsonism.MethodsWe performed a prospective observational cohort study of 60 patients presenting with early stage parkinsonism and initial uncertain diagnosis. At baseline, patients underwent a 3 T brain MRI including DTI. After clinical follow-up (mean 28.3 months), diagnoses could be made in 49 patients (30 PD and 19 AP). Conventional brain MRI was evaluated for regions of atrophy and signal intensity changes. Tract-based spatial statistics and ROI analyses of DTI were performed to analyze group differences in mean diffusivity (MD) and fractional anisotropy (FA), and diagnostic thresholds were determined. Diagnostic accuracy of conventional brain MRI and DTI was assessed with the receiver operating characteristic (ROC).ResultsSignificantly higher MD of the centrum semiovale, body corpus callosum, putamen, external capsule, midbrain, superior cerebellum, and superior cerebellar peduncles was found in AP. Significantly increased MD of the putamen was found in multiple system atrophy–parkinsonian form (MSA-P) and increased MD in the midbrain and superior cerebellar peduncles in progressive supranuclear palsy (PSP). The diagnostic accuracy of brain MRI to identify AP as a group was not improved by ROI measures of MD, though the diagnostic accuracy to identify MSA-P was slightly increased (AUC 0.82 to 0.85).ConclusionThe diagnostic accuracy of brain MRI to identify AP as a group was not improved by the current analysis approach to DTI, though DTI measures could be of added value to identify AP subgroups.

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Idiopathic Parkinson Disease

Cited by 21 publications

References 25 publications

Working memory training impacts the mean diffusivity in the dopaminergic system

Working memory training impacts the mean diffusivity in the dopaminergic system

Impact of videogame play on the brain’s microstructural properties: cross-sectional and longitudinal analyses

Conventional 3T brain MRI and diffusion tensor imaging in the diagnostic workup of early stage parkinsonism

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