Movement disorders : official journal of the Movement Disorder Society
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Subtle changes in fine motor control have been observed in individuals who carry the Huntington's disease (HD) mutation but have not yet manifested symptoms, referred to as premanifest HD (preHD). However, few studies have examined gross motor impairments in this population. This study sought to examine the role of sensory involvement in maintaining postural stability during the premanifest and manifest stages of HD using computerized dynamic posturography. ⋯ The preHD Near group showed significantly greater postural sway than the preHD Far group when visual and somatosensory information was degraded and only vestibular information was available and reliable for maintaining postural stability. The results of this study highlight subtle postural deficits in the face of changing sensory conditions in preHD up to 5 years before estimated disease onset. The findings suggest that the SOT may be a highly sensitive indicator of early motor impairment and subsequent phenoconversion to manifest HD in preHD.
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There is a consensus that in Parkinson's disease, the extent of preoperative levodopa responsiveness predicts the efficacy of subthalamic nucleus deep brain stimulation (STN DBS). However, this may be the result of statistical methods and primary assumptions. We were able to reproduce previously published correlation results on our data (N = 49 patients). ⋯ Furthermore, postoperative responses were not limited by preoperative scores, with tremor demonstrating the greatest discrepancy. We conclude that preoperative levodopa responsiveness does not predict or limit the outcome of STN DBS. These results imply different therapeutic mechanisms for levodopa and STN DBS and therefore question the validity of using substantial preoperative levodopa responsiveness as a selection criterion for STN DBS.
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Historical Article
"Trousseau's disease:" a description of the Gilles de la Tourette syndrome 12 years before 1885.
French neurologist Georges Gilles de la Tourette first described the syndrome which earned him eponymous fame in 1885. However, a publication dated 1873 by Armand Trousseau included a detailed account of what is currently know as Gilles de la Tourette syndrome (GTS). In Gilles de la Tourette's celebrated 1885 paper, there is a brief mention of the clinical picture described earlier by Trousseau, but Gilles de la Tourette somewhat disregarded it. We present the first English translation of Trousseau's description and argue that this description is more akin to modern conceptualization of GTS than the description of Gilles de la Tourette himself.
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The LRRK2 gene is a key player in Parkinson's disease (PD), however prevalence and pathogenicity of LRRK2 variants remain to be investigated in ethnically diverse populations. Herein, we performed comprehensive sequencing of the LRRK2 gene in 92 Tunisian probands with familial PD. We then performed an association study using all identified variants in a series of 167 Lrrk2 p. ⋯ None of the variants displayed significant association with risk for sporadic PD, however a trend was observed for Lrrk2 p. Y2189C. The present study underscores the importance of the LRRK2 gene in the Tunisian PD population.
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Oscillations in the beta frequency range (β-LFP) are widely distributed throughout the motor system, modulated by dopaminergic medications, and locally generated in the subthalamic nucleus (STN) and ventral intermediate nucleus of the thalamus (VIM). We investigated the feasibility of recording intraoperative β-LFP signals and their descriptive summary statistics during surgeries for deep brain stimulation (DBS). β-LFP from the microelectrode and stimulating lead were obtained from the STN in Parkinson's patients, and from the stimulating lead in the VIM of patients with Parkinson's disease or essential tremor. β-LFP power was obtained over 8 second epochs and displayed online as compressed spectral and density arrays and trend plots. In agreement with other studies, β-LFP power along microelectrode penetrations was greater in the STN as compared to sites dorsal and ventral to the nucleus. ⋯ The contact with greatest β-LFP power was either the most effective contact for clinical stimulation or adjacent to it. These results were obtained from conventional power measurements, spectral displays, and trend plots with equipment commonly used for intraoperative neuromonitoring. We conclude that β-LFP is an accessible and easily recorded signal intraoperatively with potential usefulness for DBS lead localization and clinical programming of the stimulating lead.