Postural instability is one of the most disabling features of Parkinson's disease (PD), usually occurring in the late and advanced stages of the disease. Stage III of the Hoehn-Yahr (H-Y) scale is defined by postural instability.1 the pathophysiology of postural instability in PD is still unknown and is most likely complex due to the involvement of many different neural structures. Currently, it is broadly accepted that disorders in many afferent and efferent postural systems, which normally contribute to balance control, can influence the complex pathophysiology underlying postural instability in PD. 2,3 examples include inadequately organized automatic postural reactions, poor anticipatory postural responses, difficulty in ABSTRACT: Background: Postural instability is one of the most disabling features of Parkinson's disease, usually occurring in late and advanced stages. the aim of this study was to investigate the postural performance of early-stage de novo Parkinson's disease patients with no clinical postural instability using computerized dynamic posturography. We sought to understand the relationship between postural sway and disease severity and the relationship between postural instability quantitatively measured by computerized dynamic posturography and cognitive impairment in early-stage Parkinson's disease patients. Method: thirty-one subjects with Parkinson's disease and 20 healthy controls were assessed by the computerized dynamic posturography protocol using the sensory organization test and the motor control test. a neuropsychological assessment was also administered. Results: the mean equilibrium score for sensory organization test and the vestibular input ratio were significantly correlated with Hoehn-Yahr stage. No associations between motor latency for any motor control test condition and Hoehn-Yahr stage were found. the equilibrium score for sensory organization test correlated with the mini-mental status examination scores. there was a significant correlation between motor latency for large backward translation and mini-mental status examination scores. there were significant correlations between visual perception/ construction/ memory of the neuropsychological battery test and the equilibrium score for sensory organization test and between verbal word learning test, controlled word association test and motor latency for large backward translation. Conclusion: these findings showed the postural instability present in early-stage (Hoehn-Yahr stage 2-2.5) Parkinson's disease. We also found a close relationship between postural instability and cognitive function in Parkinson's disease patients. . Une corrélation significative a été observée entre la latence motrice lors de la translation arrière de la plate-forme et les scores du MMSe. Il existait des corrélations significatives entre la perception visuelle, la construction, la mémoire évaluées par la batterie de tests neuropsychologiques et le score d'équilibre au test d'organisation sensorielle, et entre le test d'apprentissage audio-verbal...

Background: Cerebral microbleeds (CMB) are now receiving considerable attention for their association with stroke recurrence and white matter lesions (WML). Pulse wave velocity (PWV), which is a measure of arterial stiffness, was found to be one of the predictors of cardiovascular disease and stroke in a large population-based study. The current study set out to investigate the association between CMB and arterial stiffness. Methods: Subjects included 255 patients with strokes, such as cerebral infarctions or transient ischemic attacks, who were enrolled at Korea University Stroke Registry, Ansan arm, between October 2005 and May 2007, and underwent MRI and PWV. CMB, stroke lesion, stroke subtype and WML were coded by researchers blind to clinical details. Arterial stiffness was assessed by measuring brachial-ankle PWV (baPWV). Results: CMB were observed in 57 patients (22.4%), and were most frequently seen in the basal ganglia, followed by the cerebral cortex. The baPWV was significantly higher in patients with CMBs compared to those without (p < 0.01). After adjustment for demographics, vascular risk factors and hemodynamic parameters, baPWV proved to be significantly associated with CMB using a logistic regression test (odds ratio 1.119, 95% CI 1.013–1.237). Conclusions: PWV had an independent association with CMB in patients with stroke. These findings suggest that arterial stiffness may be pathophysiologically associated with CMB.