Deep brain stim

Subthalamic nucleus deep brain stimulation (STN-DBS) is an effective treatment for idiopathic Parkinson's disease. Despite recent progress, the mechanisms responsible for the technique's effectiveness have yet to be fully elucidated. The purpose of the present study was to gain new insights into the interactions between STN-DBS and cortical network activity. We therefore combined high-resolution functional near-infrared spectroscopy with low-resolution electroencephalography in seven Parkinsonian patients on STN-DBS, and measured cortical haemodynamic changes at rest and during hand movement in the presence and absence of stimulation (the ON-stim and OFF-stim conditions, respectively) in the off-drug condition...

BACKGROUND: Studies assessing personality dimensions by the "Temperament and Character Inventory" (TCI) have previously found an association between Parkinson's disease (PD) and lower Novelty Seeking and higher Harm Avoidance scores. Here, we aimed to describe personality dimensions of PD patients with motor fluctuations and compare them to a normative population and other PD populations. METHODS: All PD patients awaiting Deep Brain Stimulation (DBS) answered the TCI before neurosurgery...

PURPOSE: Postactivation depression of the Hoffmann reflex is reduced in Parkinson's disease (PD), but how the recovery is influenced by the state of the muscle is unknown. The present pilot study examined postactivation depression in PD at rest and during a voluntary contraction while patients were off treatment and while receiving medications and/or deep brain stimulation. METHODS: The authors recruited nine patients with PD treated with implanted deep brain stimulation and examined postactivation depression under four treatment conditions...

The clinical application of DBS has become manifold and there has been a tremendous growth in DBS technology in the last few decades making it safer and user friendly. The earlier concept of its delayed application in motor fluctuations of Parkinson's disease has been replaced by Class-I evidence of EARLY-STIM trial in 2013, leading to its FDA approval to be used in early-stage despite criticism. Various studies have provided evidence of beneficial effects of bilateral STN-DBS on both motor as well as nonmotor symptoms and different new targets such as the pedunculopontine nucleus, posterior subthalamic area or caudal zona incerta, centromedian-parafascicular complex, and substantia nigra pars reticulata have now become a new area of interest in addition to the subthalamic nucleus and globus pallidus internus for the alleviation of both motor and nonmotor symptoms of Parkinson's disease...

AIM: To investigate the effect of preoperative levodopa responsiveness to clinical outcomes in the first postoperative year, and to evaluate the changes in the postoperative levodopa responsiveness in patients undergoing subthalamic nucleus (STN) deep brain stimulation (DBS). MATERIAL AND METHODS: Forty-nine Parkinson?s Disease (PD) patients undergoing bilateral DBS of the STN were included in this study. Their clinical motor symptoms were assessed preoperatively by UPDRS Part III score in both OFF and ON medication states...

Background: In Deep Brain Stimulation (DBS), stimulation field steering is used to achieve stimulation spatial specificity, which is critical to obtain clinical benefits and avoid side effects. Multiple Independent Current Control (MICC) and Interleaving/Multi Stim Set (Interleaving/MSS) are two stimulation field steering paradigms in commercially available DBS systems. This work investigates the stimulation field steering accuracy and energy efficiency of these two paradigms in directional DBS. Methods: Volumes of Tissue Activated (VTAs) were generated in silico using pulse widths of 60 μs and five pulse amplitude fractionalizations intended to steer the VTAs radially in 12° steps...

Background: Deep brain stimulation (DBS) has become a standard treatment for advanced stages of Parkinson's disease, essential tremor, and dystonia. In addition to the correct surgical device implantation, effective programming is regarded to be the most important factor for clinical outcome. Despite established strategies for adjusting neurostimulation, DBS programming remains time- and resource-consuming. Although kinematic and neuronal biosignals have recently been examined as potential feedback for closed-loop DBS (CL-DBS), there is an ongoing need for programming strategies to adapt the stimulation parameters and electrode configurations accurately and effectively...

BACKGROUND: There is considerable debate regarding the use of intraoperative microelectrode recording (MER) in deep brain stimulation (DBS). OBJECTIVE: To determine if the use of intraoperative MER impacts the final position of the lead implant in DBS of the subthalamic nucleus (STN) and globus pallidus (GPi) and to evaluate the incidence of complications. METHODS: The authors conducted a retrospective chart review of all patients who underwent STN and GPi DBS with MER, at the University of Texas Health Science Center in Houston from June 1, 2009 to October 1, 2013 to compare initial and final coordinates...

Electrical stimulation of the subthalamic nucleus (STN) is clinically employed to ameliorate several symptoms of manifest Parkinson's Disease (PD). Stimulation parameters utilized by chronically implanted pulse generators comprise biphasic rectangular short (60-100 μs) pulses with a repetition frequency between 130 and 180 Hz. A better insight into the effect of electrical stimulation parameters could potentially reveal new possibilities for the improvement of deep brain stimulation (DBS) as a treatment. To this end, we employed single-sided 6-hydroxidopamine (6-OHDA) lesioning of the medial forebrain bundle (MFB) in rats to systematically investigate alternative stimulation parameters...

Background: Essential Tremor (ET) is a progressive neurological disorder characterized by postural and kinetic tremor most commonly affecting the hands and arms. Medically intractable ET can be treated by deep brain stimulation (DBS) of the ventral intermediate nucleus of thalamus (VIM). We investigated whether the location of the effective contact (most tremor suppression with at least side effects) in VIM-DBS for ET changes over time, indicating a distinct mechanism of loss of efficacy that goes beyond progression of tremor severity, or a mere reduction of DBS efficacy...

BACKGROUND: In most centers, the surgery of deep brain stimulation (DBS) is performed using a stereotactic frame. Compared with frame-based technique, frameless stereotaxy reduces the duration of surgical procedure and patient's discomfort, with lead placing accuracy equivalent after the learning curve. Although several studies have investigated the targeting accuracy of this technique, only a few studies reported clinical outcomes, with data of short-term follow-up. OBJECTIVE: To assess clinical efficacy and safety of frameless bilateral subthalamic nucleus (STN) DBS in Parkinson's disease (PD) patients at 1- and 3-year follow-up...

OBJECTIVE: Deep brain stimulation (DBS) of the ventral intermediate nucleus (VIM) is a mainstay treatment for severe and drug-refractory essential tremor (ET). Although stimulation-induced dysarthria has been extensively described, possible impairment of swallowing has not been systematically investigated yet. METHODS: Twelve patients with ET and bilateral VIM-DBS with self-reported dysphagia after VIM-DBS were included. Swallowing function was assessed clinically and using by flexible endoscopic evaluation of swallowing in the stim-ON and in the stim-OFF condition...

OBJECTIVE: Dyspnea can be present as non-motor symptom in patients with Parkinson's disease (PD). Deep brain stimulation (DBS) of the subthalamic nucleus (STN) improves motor and non-motor symptoms in PD. However, new-onset dyspnea has been reported after DBS surgery. We have studied respiratory characteristics of PD patients with bilateral STN-DBS to assess the impact of DBS on pulmonary function. METHODS: STN-DBS PD patients with dyspnea after surgery (cases) were matched with STN-DBS PD patients without dyspnea (controls)...

BACKGROUND: Parkinson's disease (PD) negatively affects patients' Quality of Life (QoL) which depends on both objective criteria such as physical health and subjective ones such as worries and norms according to personal believes. Therefore, QoL could be also associated to personality dimensions in chronic neurological diseases such as PD. OBJECTIVE: Our objective was thus to study the potential association between personality dimensions and QoL in PD patients with motor fluctuations before Deep Brain Stimulation of the Sub-Thalamic Nucleus (DBS-STN)...

Electric stimulators with precise and reliable outputs are an indispensable part of electrophysiological research. From single cells to deep brain or neuromuscular tissue, there are diverse targets for electrical stimulation. Even though commercial systems are available, we state the need for a low-cost, high precision, functional, and modular (hardware, firmware, and software) current stimulation system with the capacity to generate stable and complex waveforms for pre-clinical research. The system presented in this study is a USB controlled 4-channel modular current stimulator that can be expanded and generate biphasic arbitrary waveforms with 16-bit resolution, high temporal precision (μs), and passive charge balancing: the NES STiM (Neuro Electronic Systems Stimulator)...

To investigate the effect of multi-disciplinary teamwork on balance performance of Parkinson's disease (PD).Sixteen primary Parkinson's disease patients (8 male, 8 female) treated with bilateral subthalamic nucleus deep brain stimulation (STN-DBS) were included in the study. The median age of patients was 60.5 years; all patients were in the Hoehn&Yahr (H&Y) 3 stage; the median PD duration of the disease was 9 years. For each patient, multi-disciplinary teamwork treatment including DBS, medication, physical therapy and psychotherapy proceeded...

OBJECTIVE: Although subthalamic Deep Brain Stimulation (STN DBS) is proven effective in improving symptoms of Parkinson's Disease (PD), previous literature demonstrates a discrepancy between objective improvement and patients' perception thereof. We aimed to examine whether postoperative stimulation challenge tests (SCT) alters patients' satisfaction after STN DBS for PD. METHODS: Fifty-four PD patients underwent preoperative levodopa challenge tests and were routinely invited for SCT 1-2 years postoperatively...

OBJECTIVE: A computational model that accounts for heterogeneous tissue properties was used to compare multiple independent current control (MICC), multi-stim set (MSS), and concurrent activation (co-activation) current steering technologies utilized in deep brain stimulation (DBS) on volume of tissue activated (VTA) and power consumption. METHODS: A computational model was implemented in Sim4Life v4.0 with the multimodal image-based detailed anatomical (MIDA) model, which accounts for heterogeneous tissue properties...

BACKGROUND: The long-term effect of subthalamic nucleus deep brain stimulation (STN-DBS) on dysarthria can be detrimental. A transient beneficial effect of low-frequency stimulation (LFS) has been reported. OBJECTIVE: to investigate if the magnitude of dysarthria could predict the effect of LFS on speech in STN-DBS PD patients and to verify whether the benefit is maintained over time. METHODS: a cohort study, comparing 10 PD patients with severe speech impairment (MDS-UPDRS item 3...

OBJECTIVE: Deep brain stimulation (DBS) of the ventral intermediate thalamic nucleus (Vim) is established for medically refractory severe essential tremor (ET), but long-term efficacy is controversial. METHODS: Twenty patients with ET with DBS had standardized video-documented examinations at baseline, in the stimulation-on condition at short term (13.1 ± 1.9 months since surgery, mean ± SEM), and in the stimulator switched on and off (stim-ON/OFF) at long term; all assessments were done between 32 and 120 months (71...