The cholinergic contribution to the resting-state functional network in non-demented Parkinson's disease.

The cholinergic system arising from the basal forebrain plays an important role in cognitive performance in Parkinson's disease (PD). Here, we analyzed cholinergic status-dependent cortical and subcortical resting-state functional connectivity in PD. A total of 61 drug-naïve PD patients were divided into tertiles based on normalized substantia innominata (SI) volumes.

Dementia-Predicting Cognitive Risk Score and Its Correlation with Cortical Thickness in Parkinson Disease.

Background: We developed a risk score system to predict risks of developing dementia in individual Parkinson disease (PD) patients using baseline neuropsychological tests.

Methods: A total of 216 nondemented PD patients underwent a baseline neuropsychological evaluation and were followed up for a mean of 2.7 (±1.

A prognostic factor in focal hand dystonia: typist's cramp cases and literature review.

The prognosis of focal hand dystonia (FHD) remains unclear. We retrospectively studied six patients with typist's cramp in our hospitals, and five cases in the PubMed database. All of them were right-handed.

Cognitive and Neuroanatomical Correlates in Early Versus Late Onset Parkinson's Disease Dementia.

Background: Aging is the most important risk factor of development of dementia in Parkinson's disease (PD), but there are no data on clinical and radiological heterogeneity of PD dementia (PDD) depending on age at onset.

Objectives: The goal of this study was to examine whether patients with PDD are clinically and radiologically heterogeneous depending on age at onset.

Methods: A total of 116 patients with PD dementia and 121 age- and sex-matched normal controls were enrolled.

Striatal Dopamine Depletion Patterns and Early Non-Motor Burden in Parkinsons Disease.

Background: The mechanism underlying non-motor symptoms in Parkinson's disease has not yet been elucidated. In this study, we hypothesized that Parkinson patients with more non-motor symptoms have a different pattern of striatal dopamine depletion, particularly in areas other than the sensorimotor striatum, compared to those with fewer non-motor symptoms.

Methods: We conducted a prospective survey of the degree of non-motor symptoms (using the Korean version of the Non-Motor Symptoms Scale; K-NMSS) in 151 patients with early-stage Parkinson's disease who had undergone a dopamine transporter PET scan as an initial diagnostic procedure.

Posterior Ventricular Enlargement to Differentiate Dementia with Lewy Bodies from Alzheimer's Disease.

Background: Enlargement of the lateral ventricle is observed in dementia associated with Alzheimer's disease (AD) and dementia with Lewy bodies (DLB).

Objective: The degree of anteroposterior ventricular enlargement and its correlation with clinical and neuropsychological features were investigated in DLB patients.

Methods: Forty-eight patients with DLB, 76 with AD, and 45 subjects with normal cognition (NC) underwent structural brain MRI and detailed neuropsychological tests.

Effect of olfactory impairment and white matter hyperintensities on cognition in Parkinson's disease.

Introduction: Although white matter hyperintensities (WMH) and olfactory dysfunction are independently associated with the cognitive impairments in Parkinson's disease (PD), the effects of simultaneous presence of these abnormalities remain unknown. Thus, we investigated the different effects of deep WMH and periventricular WMH on olfactory and cognitive performance and evaluated the additive effects of the concurrent presence of WMH and olfactory dysfunction on cognitive performance in PD.

Methods: We enrolled 171 patients with non-demented PD whose WMH scores were assessed using a semi-quantitative visual rating system.

Apathy and striatal dopamine defects in non-demented patients with Parkinson's disease.

Introduction: Apathy is a common, disabling symptom in Parkinson's disease (PD). The mechanisms underlying apathy in PD are still unclear, although they may be related to dysfunction in the meso-cortico-limbic circuit, including the ventral striatum. Thus, we performed this study to investigate whether dopamine depletion in the ventral striatum contributes to apathy in PD.

Comparison of regional brain atrophy and cognitive impairment between pure akinesia with gait freezing and Richardson's syndrome.

Pure akinesia with gait freezing (PAGF) is considered a clinical phenotype of progressive supranuclear palsy. The brain atrophy and cognitive deficits in PAGF are expected to be less prominent than in classical Richardson's syndrome (RS), but this hypothesis has not been explored yet. We reviewed the medical records of 28 patients with probable RS, 19 with PAGF, and 29 healthy controls, and compared cortical thickness, subcortical gray matter volume, and neuropsychological performance among the three groups.

Gender Differences in Age-Related Striatal Dopamine Depletion in Parkinson's Disease.

Objective: Gender differences are a well-known clinical characteristic of Parkinson's disease (PD). In-vivo imaging studies demonstrated that women have greater striatal dopamine transporter (DAT) activity than do men, both in the normal population and in PD patients. We hypothesize that women exhibit more rapid aging-related striatal DAT reduction than do men, as the potential neuroprotective effect of estrogen wanes with age.

Nigrostriatal dopamine-independent resting-state functional networks in Parkinson's disease.

As an indicator of synchronous neural activity, resting-state functional networks are influenced by neuropathological and neurochemical changes in degenerative diseases. To further advance understanding about neurochemical and neuropathological basis for resting-state functional maps, we performed a comparative analysis of resting-state functional connectivity in patients with Parkinson's disease (PD) and drug induced parkinsonism (DIP). Resting-state neuroimaging data were analyzed with a seed-based approach to investigate striatocortical functional connectivity and cortical functional connectivity within the default mode network, executive control network, and the dorsal attention network.

Topography of cortical thinning associated with white matter hyperintensities in Parkinson's disease.

Background: Although white matter hyperintensities (WMHs) are associated with cognitive impairments in Parkinson's disease (PD), the relationships between WMHs and cortical atrophy in regard to cognitive impairments are unknown. Here, we investigated the topography of cortical thinning related to deep (DWMHs) and periventricular WMHs (PWMHs) and their differential impacts on cognitive performance in PD.

Methods: We enrolled 87 patients with non-demented PD and evaluated WMH scores using a semi-quantitative visual rating system.

Olfactory performance and resting state functional connectivity in non-demented drug naïve patients with Parkinson's disease.

Olfactory performance in Parkinson's disease (PD) is closely associated with subsequent cognitive decline. In the present study, we analyzed the olfaction-dependent functional connectivity with a hypothesis that olfactory performance would influence functional connectivity within key brain areas of PD. A total of 110 nondemented drug-naïve patients with PD were subdivided into three groups of high score (PD-H, n = 23), middle score (PD-M, n = 64), and low score (PD-L, n = 23) based on olfactory performance.

Apathy and olfactory dysfunction in early Parkinson's disease.

Objective: Olfactory and emotional dysfunctions are very common in patients with Parkinson's disease (PD). Olfaction and emotions share common neuroanatomical substrates. Therefore, in this study, we evaluated the association between olfactory and emotional dysfunctions in patients with PD.

Cognitive and cortical thinning patterns of subjective cognitive decline in patients with and without Parkinson's disease.

Background: Subjective cognitive decline (SCD) has gained attention as a predictor of future cognitive decline in neurodegenerative diseases. Based on the hypothesis that different pathologies may distinctly contribute to SCD, we investigated the cognitive profiles and cortical thickness of patients with SCD, with and without Parkinson's disease (PD).

Methods: In total, 96 patients experiencing SCD were classified as having PD (SCD-PD(+), n = 49) or no neurological disease (SCD-PD(-), n = 47); cognitively normal subjects without SCD (n = 23) were included as controls.

Dopaminergic modulation of resting-state functional connectivity in de novo patients with Parkinson's disease.

Parkinson's disease (PD) is characterized by degenerative changes of nigral dopamine neurons, resulting in the dopaminergic denervation of the striatum. Resting state networks studies have demonstrated that dopamine modulates distinct network connectivity patterns in both a linear and a nonlinear fashion, but quantitative analyses of dopamine-dependent functional connectivity secondary to PD pathology were less informative. In the present study, we performed a correlation analysis between striatal dopamine levels assessed quantitatively by FP-CIT positron emission tomography imaging and resting-state functional connectivity in 23 drug naïve de novo patients with PD to elucidate dopamine-dependent functional networks.

Cerebral microbleeds in patients with Parkinson's disease.

Cerebral microbleeds (CMBs) are known to be associated with cognitive impairments in the elderly and in patients with various diseases; however, the nature of this association has not yet been evaluated in Parkinson's disease (PD). In the present study, we analyzed the incidence of CMBs in PD according to cognitive status, and the impact of CMBs on cognitive performance was also evaluated. The CMBs in PD with dementia (n = 36), mild cognitive impairment (MCI, n = 46), or cognitively normal (n = 41) were analyzed using conventional T2*-weighted gradient-recalled echo images.

Presynaptic dopamine depletion predicts levodopa-induced dyskinesia in de novo Parkinson disease.

Objective: To investigate whether the magnitude of presynaptic dopamine depletion is a risk factor for the development of levodopa-induced dyskinesia (LID) in Parkinson disease (PD) by quantitatively analyzing (18)F-FP-CIT PET data.

Methods: This retrospective cohort study enrolled a total of 127 drug-naive de novo patients with PD who completed (18)F-FP-CIT PET scanning at their initial evaluation. The patients visited our outpatient clinic every 3-6 months and had been followed for a minimum of 2 years since beginning dopaminergic medication.

Subjective cognitive decline predicts future deterioration in cognitively normal patients with Parkinson's disease.

Increasing evidence suggests that subjective cognitive decline (SCD) is a potential predictor of future cognitive decline or dementia. We investigated whether SCD in patients with Parkinson's disease (PD) is a predictor of future cognitive decline. Forty-six cognitively normal patients with PD were selected using comprehensive neuropsychological tests, and classified depending on the presence (PD-SCD(+), n = 25) or absence of SCD (PD-SCD(-), n = 21).

Olfactory performance acts as a cognitive reserve in non-demented patients with Parkinson's disease.

Objective: To explore whether olfactory performance acts as a cognitive reserve in non-demented patients with Parkinson's disease (PD).

Methods: Patients with non-demented PD (n = 119) underwent T1-weighted MRI and olfactory identification tests. According to their olfactory performance, PD patients were subdivided into three groups of high score (PD-H, n = 38), middle score (PD-M, n = 48), and low score (PD-L, n = 33).

Factors related to the initial stroke severity of posterior circulation ischemic stroke.

Background: Posterior circulation (PC) stroke, which was previously less well known than anterior circulation (AC) stroke, has become more identified due to the development of imaging equipment. Recently, the initial stroke severity assessed by the NIH Stroke Scale (NIHSS) was reported as a useful measure for predicting the outcome of PC as well as AC stroke. The aim of our study was to investigate the factors related to the stroke severity of PC ischemic stroke as assessed by the baseline NIHSS and the predictors of progressive neurological deficit and 3-month outcome.