In-Uk Song

Poststroke Restless Legs Syndrome and Lesion location : Anatomical Considerations

Several case studies have reported on restless legs syndrome (RLS) associated with stroke. In this study, we investigated the prevalence and the lesion topography of poststroke RLS. There were 137 patients with ischemic stroke included in this study. The diagnosis of RLS was made 1 month after the index stroke using the criteria established by the International RLS Study Group. All patients enrolled underwent magnetic resonance imaging within 7 days of the onset of the stroke. The prevalence of stroke‐related RLS was calculated, and the topography of the associated ischemic lesions was analyzed. Among 137 patients, 17 patients (12.4%) were diagnosed with RLS after a stroke. Stroke‐related RLS was found in 10 out of 33 patients with a basal ganglia/corona radiata infarct (30.3%), 1 out of 8 patients with an internal capsular infarct (12.5%), and 1 out of 7 patients with a thalamic infarct (14.3%). In addition, one out of 54 with a cortical lesion with/without subcortical involvement (1.9%), and 4 out of 18 patients with a pontine lesion (22.2%) had RLS. The analysis of the lesions in the cortical and subcortical group showed only 1 patient in the cortical group had stroke‐related RLS, whereas 16 in the subcortical group had stroke‐related RLS. The results of this study suggest that lesions of the subcortical brain areas such as the pyramidal tract and the basal ganglia‐brainstem axis, which are involved in motor functions and sleep‐wake cycles, may lead to RLS symptoms in patients after an ischemic stroke.

Image-Guided Transcranial Focused Ultrasound Stimulates Human Primary Somatosensory Cortex

Focused ultrasound (FUS) has recently been investigated as a new mode of non-invasive brain stimulation, which offers exquisite spatial resolution and depth control. We report on the elicitation of explicit somatosensory sensations as well as accompanying evoked electroencephalographic (EEG) potentials induced by FUS stimulation of the human somatosensory cortex. As guided by individual-specific neuroimage data, FUS was transcranially delivered to the hand somatosensory cortex among healthy volunteers. The sonication elicited transient tactile sensations on the hand area contralateral to the sonicated hemisphere, with anatomical specificity of up to a finger, while EEG recordings revealed the elicitation of sonication-specific evoked potentials. Retrospective numerical simulation of the acoustic propagation through the skull showed that a threshold of acoustic intensity may exist for successful cortical stimulation. The neurological and neuroradiological assessment before and after the sonication, along with strict safety considerations through the individual-specific estimation of effective acoustic intensity in situ and thermal effects, showed promising initial safety profile; however, equal/more rigorous precautionary procedures are advised for future studies. The transient and localized stimulation of the brain using image-guided transcranial FUS may serve as a novel tool for the non-invasive assessment and modification of region-specific brain function.

Influence of white matter hyperintensities on the cognition of patients with Parkinson disease.

BackgroundWhite matter hyperintensities (WMH) have been associated with cognitive impairment in elderly persons and in patients with Alzheimer disease. However, the role of WMH in Parkinson disease (PD) dementia remains to be elucidated. MethodsThe cohort for this study comprised 71 consecutive patients with PD, all of whom completed a clinical assessment, neuropsychologic investigation, and magnetic resonance imaging of brain. WMH were rated using the semiquantitative visual rating system proposed by Scheltens et al. ResultsThe PD dementia group had significantly more WMH than the PD without dementia group in the evaluated brain regions except for the infratentorial area. The WMH showed a significant correlation with age, Unified Parkinsons Disease Rating Scale, Mini-Mental State Examination, sum of the box of Clinical Dementia Rating, and many of the cognitive domains. The linear regression model showed that the WMH was independently associated with cognitive impairment in patients with PD, regardless of age, sex, duration or severity of PD symptoms, and vascular risk factors. ConclusionsThese findings confirm that WMH might be associated with cognitive decline in patients with PD, regardless of age, sex, education status, duration or severity of PD symptoms, and vascular risk factors. This result suggests that other nonvascular factors contribute to the progression of dementia in patients with PD.

The prevalence and patterns of pharyngoesophageal dysmotility in patients with early stage Parkinson's disease†

Dysphagia occurs in the majority of patients with Parkinsons disease (PD) and is known to correlate with abnormalities of oropharyngeal function. The aim of this study was to evaluate pharyngoesophageal activity in patients with early‐stage PD. Newly diagnosed PD patients with a symptom duration not exceeding 3 years were included. All PD patients were questioned about symptoms of dysphagia and underwent combined multichannel intraluminal impedance manometry and multiple rapid swallow tests. Fifty‐four patients (22 men and 32 women, 67.1 ± 10.3 years) were enrolled. The duration of Parkinsonian motor symptoms was 11.5 ± 8.8 months, the Hoehn and Yahr stage was 1.6 ± 0.4, and the total Unified Parkinsons Disease Rating Scale was 25.1 ± 18.6. Esophageal manometry in the liquid swallow and viscous swallow tests was abnormal in 22 (40.7%) and 31 (67.4%) patients, respectively. Although manometric abnormalities were more common in patients with more severe dysphagia symptoms, many patients with no or minimal symptoms also had manometric abnormalities. Repetitive deglutition significantly correlated with failed peristalsis and incomplete bolus transit. Abnormal responses to multiple rapid swallow tests were found in 33 out of 54 patients; 29 with incomplete inhibition (repetitive contraction) and 4 with failed peristalsis. These results suggest that the majority of patients with early‐stage PD showed pharyngeal and esophageal dysfunction even before clinical manifestations of dysphagia, which may reflect selective involvement of either the brain stem or the esophageal myenteric plexus in early‐stage PD.

Relationship between High-Sensitivity C-Reactive Protein and Clinical Functional Outcome after Acute Ischemic Stroke in a Korean Population

Background: High-sensitivity C-reactive protein (hs-CRP) has been shown to be a powerful predictor of coronary ischemic events. However, the prognosis of functional disability in patients with cerebrovascular disease has not been well established. Therefore, we performed this study to determine the prognostic significance of hs-CRP levels in patients with functional disability after acute ischemic stroke. Methods: A total of 417 Korean patients with ischemic stroke were examined within 24 h after symptom onset. hs-CRP measurements were obtained on admission and on the seventhhospital day. The correlations between the concentration of hs-CRP and functional disability duration 12 months after stroke onset were analyzed. Results: The present study showed that hs-CRP levels on admission and on the seventh hospital day were significantly correlated with the modified Rankin Scale (mRS) score 12 months after stroke onset. These results also demonstrated that mRS scores are more closely associated with hs-CRP levels on the seventh hospital day than hs-CRP levels on admission. Conclusion: This study demonstrated that elevated hs-CRP levels on the seventh hospital day, rather than within 24 h after stroke onset, could strongly predict the prognosis of functional disability. These results supported that hs-CRP is a useful marker of ischemic stroke in the Korean population.

Clinical Significance of Silent Cerebral Infarctions in Patients With Alzheimer Disease

BackgroundAlthough recent advances in the epidemiology of Alzheimer disease (AD) suggest a strong association between vascular factors predisposing to cerebrovascular disease and AD, the results of many studies on the relation between cerebrovascular disease and AD have been yet controversial. Therefore, we conducted this study to clarify the relation between concomitant silent cerebral infarctions and the cognitive decline of AD patients. MethodsOne hundred and fifty subjects participated in this study: 51 patients had AD, 44 patients had AD with silent cerebral infarction (ADI), and there were 45 control subjects. These subjects received the global cognitive function testing and they were all evaluated with detailed neuropsychologic tests including attention, memory, language, and also the visuospatial and frontal function. ResultsCompared with the control group, the patients with AD and ADI demonstrated significantly impairments in all cognitive domains. The ADI group showed more marked impairment than did the AD group on the domains including the language function, the delayed recall test, and semantic fluency. ConclusionsADI showed more severe cognitive decline than AD, indicating that cerebrovascular disease contributes to the severity of cognitive decline. These results suggest that prevention of cerebrovascular disease can play an important role in preventing the rapid cognitive decline of AD.

Color vision in Parkinson’s disease and essential tremor

Background and purpose:  Decreased visual function is one of the non‐motor dysfunctions of Parkinson’s disease (PD). Recent evidences suggest that essential tremor (ET) is not ‘pure’ motor disorder and there is growing evidence that this disease is a multiple‐system disorder. In some cases, it is difficult to differentiate ET from PD. In addition, there is considerable controversy regarding the relationship between PD and ET. The objective of this study was to compare color discrimination dysfunction amongst patients with PD and ET and to investigate the clinical relevance.

Is There an Association between the Level of High-Sensitivity C-Reactive Protein and Idiopathic Parkinson’s Disease? A Comparison of Parkinson’s Disease Patients, Disease Controls and Healthy Individuals

Background: High-sensitivity C-reactive protein (hs-CRP) is a sensitive systemic marker of inflammation, and increased levels of hs-CRP are associated with inflammatory reactions. Microglia-mediated neuroinflammation has been hypothesized to play an important role in the pathogenesis of idiopathic Parkinson’s disease (PD). However, the clinical value of hs-CRP in PD is poorly defined. Therefore, we conducted this study to investigate the clinical value of hs-CRP in patients with PD. Methods: We examined 212 patients with de novo PD, 253 patients with acute ischemic cerebrovascular disease and 119 healthy subjects and investigated the differences in hs-CRP among these 3 groups. The PD group was classified into 4 subgroups according to the Hoehn and Yahr stage to investigate the relationship between hs-CRP and symptom severity. Results: There was no significant difference in the hs-CRP value between the PD and the ischemic cerebrovascular disease groups, but the subjects in the 2 disease groups demonstrated higher hs-CRP levels than those in the normal control group. A post-hoc analysis of the 4 PD subgroups showed no significant differences in hs-CRP values. In addition, this study demonstrated that the odds ratio of the PD group by hs-CRP was 2.037 (95% CI 1.180–3.517; p = 0.011). Conclusion: We suggest that our results could support the hypothesis that neuroinflammation contributed to the pathogenesis of PD and cautiously assume that elevated hs-CRP might have a clinical value as a risk factor for PD.

Cognitive Impairment in Essential Tremor without Dementia

Background and purpose Several clinical studies have demonstrated that patients with essential tremor (ET) may have cognitive deficits; however, there are no published data regarding detailed neuropsychological assessments of ET without dementia. We therefore conducted a case-control study of cognitive function in patients with ET. Methods The cohort for this study comprised 34 consecutive patients with ET without dementia and 33 age-matched controls, all of who completed a dementia-screening questionnaire and underwent a detailed neuropsychological investigation. Results Severe impairments were observed in most domains for the ET group compared to the controls, including attention, part of language function, verbal memory, and frontal executive functions. Conclusions Our results support the finding that the subclinical cognitive deficits characterized by attention, verbal memory impairments, and executive dysfunction are a clinical feature of ET. In addition, our results also support the finding that age at examination and educational status are the most important risk factors associated with cognitive deficits in patients with ET.

Effects of zonisamide on isolated head tremor

Background and purpose:  The medical treatment available for patients with essential tremor (ET) is often inadequate. Furthermore, the efficacy of the medical treatments currently available for patients with ET of cranial nerve areas is less satisfactory than that of the medical treatments available for patients with ET involving the upper extremities. This pilot study was performed to evaluate whether zonisamide (ZNS) is effective in the treatment of patients with isolated head tremor.