J Volkmann

..To assess the neuropsychiatric consequences of DBS in patients with PD we did an ancillary protocol as part of a randomised study that compared DBS with the best medical treatment...

..Replacement of pallidal electrodes into the subthalamic nucleus in four patients could restore the initial benefit of deep brain stimulation and allowed a significant reduction of dopaminergic drug therapy...

..Here, we summarize the neuropsychiatric changes observed after STN HFS and try to disentangle their various etiologies...

..They also describe noninvasive technical trouble shooting by using programming features of the commercially available neurostimulation devices...

..This article discusses the different factors influencing patient selection for surgical treatment and describes standardized methods and the caveats for clinical documentation of treatment results in dystonia...

..Current evidence suggests that for patients fulfilling these selection criteria deep brain stimulation of the subthalamic nucleus is superior to standard oral drug therapy in maintaining a good level of health-related quality of life...

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..The basic programming algorithms for thalamic, subthalamic, and pallidal stimulation in PD are explained and summarized in flowcharts...

..Despite sustained motor improvements many of these initial benefits were lost after 3 years. This may reflect either progression of the disease or adaptive changes in the subjective perception of health-related wellbeing over time...

..Recently, deep brain stimulation of the posterior hypothalamus has been shown to be effective in the treatment of drug-resistant chronic cluster headache...

..The goal of this study was to determine the relation and size of these artefacts to the electrodes by comparing the position of the electrodes in postoperative MR and CT imaging...

..In addition, they emphasize abnormalities in the patterning and dynamics of neuronal discharges in the parkinsonian STN, which support current concepts of abnormal motor loop oscillations in Parkinson's disease...

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..In this study, we assessed whether modulation of basal ganglia activity by high-frequency stimulation of the subthalamic nucleus (STN-HFS) in PD had an impact on the brainstem-controlled startle system...

..We present our technique for direct preoperative visualization of the target using a fast spin-echo inversion-recovery (FSE-IR) sequence...

..These advantages contrasted with a need for more intensive postoperative monitoring and a higher incidence of adverse events related to levodopa withdrawal...

..To evaluate the usefulness of a new instrument for bedside testing of proximal arm and distal finger tapping performance in patients with Parkinson's disease (PD)...

..We propose that pallidofugal fiber tracts play a major role in the etiopathology of dyskinesias and their blockade through DBS may explain our observations...

..Our data support the pathophysiological model of a decreased basal ganglia output in dystonia and argue against a possible pharmacological artifact...

..Hence, the increase in gait velocity in the STN group was almost exclusively due to a significant increase in step length, while in the GPi group statistically non-significant increases in both step length and cadence contributed...

..Ethanol may act via an influence of the inferior olive or directly on alcohol-sensitive gamma-aminobutyric acid receptors within the cerebellum...

..The site of permanent stimulation is the subject of ongoing debate, as stimulation both within and adjacent to the subthalamic nucleus may be effective...

..Further studies should specifically address the questions of efficacy and side effects as well as the impact on quality of life...

..Prior to this surgery the patient had experienced a striking but short lived amelioration of symptoms with clozapine therapy...

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..Presenting our clinical series of 179 patients operated upon since 1999, the indications, risks and benefits for the patients are discussed in order to further improve the techniques and their applications...

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..We propose that this cortical projection pattern forms the neurophysiological basis of the low temporal and spatial resolution of conscious visceral sensation...

..Hence, the question arises whether the disrupted sleep pattern in Parkinson's disease (PD) is responsive to dopaminergic treatment...

..7 SD of the motor part of the Burke-Fahn-Marsden Dystonia Rating Scale) improvement of dystonia and functional disability without adverse events...

..The authors investigated the effect of high frequency stimulation of the subthalamic nucleus (STN-HFS) on autogenic inhibition in PD...

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..The main frequency of cerebro-cerebral coupling corresponds to double the tremor frequency...

..01). STN-HFS restores the normal facilitatory drive of a transcranially evoked motor cortical response to the spinal motoneuron pool. In addition to subcortical routes, STN-DBS also alters spinal excitability via transcortical pathways...

..7 +/- 2.6 (P < 0.001) whereas levodopa had no impact (R(2) reduction 3.7 +/- 1.6, P = 0.081). This demonstrates that STN-DBS, by reducing motor perseveration, influences higher order aspects of motor behavior of patients with PD...

..Parkinsonian patients demonstrate particular difficulties when performing sequential motor tasks compared to simple movements indicating an important role of the basal ganglia in switching between different motor programs...

..However, prospective studies for this procedure are lacking and some clinical problems may be more easily solved with targeting the internal pallidum or the thalamus. Despite major progress in this field, much work remains to be done...

..Future controlled multicentre trials will need to confirm this open-label experience and should help to better define predictive factors for non-responders...

..They did not find any significant change in tremor severity as measured by clinical ratings or accelerometry...

..Renewed dislocation of revised extensions may be prevented by securing the position of the connector (e.g. with manipulates)...

..18 mm (range 0.42 to 1.93 mm). These data suggest that both approaches may be used to determine the position of single electrode contacts...

..Neurostimulation of the subthalamic nucleus reduces levodopa-related motor complications in advanced Parkinson's disease. We compared this treatment plus medication with medical management...

..These results provide evidence for a homeostatic response pattern in the human M1(HAND) that integrates acute plastic changes evoked through different "input channels."..

..It has been hypothesized that the basic and first harmonic frequency of Parkinsonian tremor are somewhat independent oscillations the biological basis of which remains unclear...

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..These results demonstrate a functional independence of implicit cognitive skill learning and certain aspects of executive functions...

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..Since less pharmacotherapy is needed after STN stimulation, reduced levodopa intake results in relative improvement of autonomic function in deep brain stimulated PD patients...

..These results demonstrate a single dissociation of depressive symptoms and anhedonia in response to an acute L-dopa and STN-stimulation challenge...

..The report has been endorsed by the Scientific Issues Committee of the Movement Disorder Society and the American Society of Stereotactic and Functional Neurosurgery...

..The better efficacy of stimulation within the STA compared to thalamus proper favours the concept of a modulation of cerebello-thalamic projections underlying the improvement of these symptoms...

..This argues for different mechanisms that underlie the changes in task-switching behavior in healthy aging and PD...

..The data suggest that STN-DBS ameliorates bladder dysfunction and that this modulation may result from facilitated processing of afferent bladder information...

..Thus, coherent psychogenic tremor would be in keeping with voluntarily produced oscillations. Absent coherence is an indication of another, possibly nonvoluntary mechanism like clonus or enhanced physiologic tremor...

..One reason is the substantial fluctuation of tremor severity over time, which is difficult to capture and may render momentary clinical assessments unreliable...

..g., zona incerta, were significantly less effective. We suggest that the dorsolateral STN border should be covered by STN-DBS...

..The current series demonstrates efficacy and safety of STN-DBS beyond the first year after surgical procedure. Complications of STN-DBS comprise a wide range of psychiatric adverse events which, however, were temporary...

..The cause of camptocormia in idiopathic PD is a focal myopathy. Our findings suggest that the myopathy has a progressive course, which finally leads to degeneration of the paravertebral muscles...

..Furthermore, this is the first imaging study, which shows an effect of STN-DBS on sensory gating in PD patients and its neural basis...

..The present study provides first data of an important number of patients on clinical effectiveness and expenses in relation to STNDBS...

..In a series of 16 patients, we demonstrated that subthalamic deep brain stimulation has a significant and urodynamically recordable effect leading to a normalization of pathologically increased bladder sensibility...

..Yet only few studies have been published to date regarding this treatment. We present the results of DBS of the GPi in 17 patients with severe dystonia of different causes...

..This emphasizes a role of the sensorimotor part of the internal globus pallidus in regulating speech fluency...

..These findings, based on two case reports, highlight the pivotal role of the GPi in mediating dyskinesia-related neural activity within the basal ganglia loop...

..His speech was affected exclusively while reciting Islamic prayers in Arabic language, which he otherwise did not speak...

..Although heterozygous variants are present in a considerable number of patients, they are-based on this relatively small sample-not significantly more frequent in patients compared to controls...

..The impact of DBS on the progression and life expectancy in PKAN is unknown. We present a 5-year outcome and video documentation of bilateral GPi-DBS of an adolescent patient suffering from genetically defined PKAN...

..CONCLUSIONS: Bilateral pallidal neurostimulation for 3 months was more effective than sham stimulation in patients with primary generalized or segmental dystonia. (ClinicalTrials.gov number, NCT00142259 [ClinicalTrials.gov].)...

..The goal of this study was to relate the degree of clinical improvement and that of energy consumption to the anatomical position of electrode poles used for long-term stimulation...

..Clinical observations indicate additional influence on emotional behavior...

..The open-label extension phase resulted in a significant improvement in all SF-36 domains following 6 months of neurostimulation. These results demonstrate a favorable impact of DBS on HRQoL in primary dystonia...

..The demented Parkinsonian patients then present with improvement in cognitive function while motor skills do not deteriorate...

..New dopamine agonists pramipexole and ropinirole appear to ameliorate depressive symptoms in PD in addition to effects on motor symptoms. There is a lack of appropriate rating scales and controlled studies regarding depression in PD...

..Jens Volkmann, MD, discusses selection criteria for STN DBS and duodenal L-dopa/carbidopa infusion. Teus van Laar, MD, PhD, and Ad Hovestadt, MD, discuss the first data from a Dutch cohort study of duodenal L-dopa/carbidopa...

..Of note, 1 of the affected premutation carriers had a heterozygous Parkin mutation...