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"Prokop, Thomas"
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One-pass deep brain stimulation of dentato-rubro-thalamic tract and subthalamic nucleus for tremor-dominant or equivalent type Parkinson’s disease
by
Piroth, Tobias
,
Urbach, Horst
,
Rijntjes, Michel
in
Aged
,
Clinical - Functional
,
Clinical Article - Functional
2016
Background
Refractory tremor in tremor-dominant (TD) or equivalent-type (EQT) idiopathic Parkinson’s syndrome (IPS) poses the challenge of choosing the best target region to for deep brain stimulation (DBS). While the subthalamic nucleus is typically chosen in younger patients as the target for dopamine-responsive motor symptoms, it is more complicated if tremor does not (fully) respond under trial conditions. In this report, we present the first results from simultaneous bilateral DBS of the DRT (dentato-rubro-thalamic tract) and the subthalamic nucleus (STN) in two elderly patients with EQT and TD IPS and dopamine-refractory tremor.
Methods
Two patients received bilateral octopolar DBS electrodes in the STN additionally traversing the DRT region. Achieved electrode positions were determined with helical CT, overlaid onto DTI tractography data, and compared with clinical data of stimulation response.
Results
Both patients showed immediate and sustained improvement of their tremor, bilaterally.
Conclusions
The proposed approach appears to be safe and feasible and a combined stimulation of the two target regions was performed tailored to the patients’ symptoms. Clinically, no neuropsychiatric effects were seen. Our pilot data suggest a viable therapeutic option to treat the subgroup of TD and EQT IPS and with tremor as the predominant symptom. A clinical study to further investigate this approach (OPINION:
www.clinicaltrials.gov
; NCT02288468) is the focus of our ongoing research.
Journal Article
Postoperative neuroimaging analysis of DRT deep brain stimulation revision surgery for complicated essential tremor
by
Urbach, Horst
,
Skodda, Sabine
,
Li, Meng
in
Aged
,
Deep Brain Stimulation - methods
,
Diffusion Tensor Imaging - methods
2017
Background
We report a patient who received conventional bilateral deep brain stimulation of the ventral intermediate nucleus of thalamus (Vim) for the treatment of medication refractory essential tremor (ET). After initial beneficial effects, therapeutic efficacy was lost due to a loss of control of his proximal trunkal and extremity tremor. The patient received successful diffusion tensor magnetic resonance imaging fiber tractographic (DTI FT)-assisted DBS revision surgery targeting the dentato-rubro-thalamic tract (DRT) in the subthalamic region (STR).
Objective
To report the concept of DTI FT-assisted DRT DBS revision surgery for ET and to show sophisticated postoperative neuroimaging analysis explaining improved symptom control.
Methods
Analysis was based on preoperative DTI sequences and postoperative helical computed tomography (hCT). Leads, stimulation fields, and fibers were reconstructed using commercial software systems (Elements, Brainlab AG, Feldkirchen, Germany; GUIDE XT, Boston Scientific Corp., Boston, MA, USA).
Results
The patient showed immediate and sustained tremor improvement after DTI FT-assisted revision surgery. Analysis of the two implantations (electrode positions in both instances) revealed a lateral and posterior shift in the pattern of modulation of the cortical fiber pathway projection after revision surgery as compared to initial implantation, explaining a more efficacious stimulation.
Conclusions
Our work underpins a possible superiority of direct targeting approaches using advanced neuroimaging technologies to perform personalized DBS surgery. The evaluation of DBS electrode positions with the herein-described neuroimaging simulation technologies will likely improve targeting and revision strategies. Direct targeting with DTI FT-assisted approaches in a variety of indications is the focus of our ongoing research.
Journal Article
Rebound Tremor Frequency as a Potential Diagnostic Marker for Delayed Therapy Escape after Thalamic Deep Brain Stimulation for Essential Tremor—Insights from a Cross-Sectional Study
by
Walz, Isabelle D.
,
Aiple, Franz
,
Frommer, Marvin L.
in
Ataxia
,
Cross-sectional studies
,
Deep brain stimulation
2024
Delayed therapy escape (DTE) is frequent after thalamic deep brain stimulation for essential tremor, leading to reduced quality of life, often with ataxic symptoms, and early recognition is challenging. Our goal was to examine whether a low-frequency rebound tremor of the left hand after switching off stimulation is useful as a diagnostic marker for DTE. In this cross-sectional study with additional retrospective analysis, we examined 31 patients with bilateral thalamic DBS ≥ 12 months for essential tremor, using quantitative assessments including video-based motion capture, Fahn–Tolosa–Marin Tremor Rating Scale (FTMTRS), and scale for the assessment and rating of ataxia (SARA). If available, preoperative (preOP) and 12-month postoperative assessments were included in the analysis. Evaluations occurred with DBS activated (ON) and deactivated (OFF). A higher ratio FTMTRS nowON/preOP indicated DTE. Preoperative FTMTRS scores were available for 16 patients, including 5 patients with DTE. The receiver operating characteristic analysis found an area under the curve of 0.86 (p = 0.024) for identification of DTE by low-frequency rebound tremor (i.e., OFF) on the left. In conclusion, it could serve as a potential diagnostic marker.
Journal Article
The dentato-rubro-thalamic tract as the potential common deep brain stimulation target for tremor of various origin: an observational case series
by
Piroth, Tobias
,
Jenkner Carolin
,
Reinacher Peter Christoph
in
Deep brain stimulation
,
Dystonia
,
Magnetic resonance imaging
2020
IntroductionDeep brain stimulation alleviates tremor of various origins. The dentato-rubro-thalamic tract (DRT) has been suspected as a common tremor-reducing structure. Statistical evidence has not been obtained. We here report the results of an uncontrolled case series of patients with refractory tremor who underwent deep brain stimulation under tractographic assistance.MethodsA total of 36 patients were enrolled (essential tremor (17), Parkinson’s tremor (8), multiple sclerosis (7), dystonic head tremor (3), tardive dystonia (1)) and received 62 DBS electrodes (26 bilateral; 10 unilateral). Preoperatively, diffusion tensor magnetic resonance imaging sequences were acquired together with high-resolution anatomical T1W and T2W sequences. The DRT was individually tracked and used as a direct thalamic or subthalamic target. Intraoperative tremor reduction was graded on a 4-point scale (0 = no tremor reduction to 3 = full tremor control) and recorded together with the current amplitude, respectively. Stimulation point coordinates were recorded and compared to DRT. The relation of the current amplitude needed to reduce tremor was expressed as TiCR (tremor improvement per current ratio).ResultsStimulation points of 241 were available for analysis. A total of 68 trajectories were tested (62 dB leads, 1.1 trajectories tested per implanted lead). Tremor improvement was significantly decreasing (p < 0.01) if the distance to both the border and the center of the DRT was increasing. On the initial trajectory, 56 leads (90.3%) were finally placed. Long-term outcomes were not part of this analysis.DiscussionTremor of various origins was acutely alleviated at different points along the DRT fiber tract (above and below the MCP plane) despite different tremor diseases. DRT is potentially a common tremor-reducing structure. Individual targeting helps to reduce brain penetrating tracts. TiCR characterizes stimulation efficacy and might help to identify an optimal stimulation point.
Journal Article
Pallidal neurostimulation in patients with medication-refractory cervical dystonia: a randomised, sham-controlled trial
2014
Cervical dystonia is managed mainly by repeated botulinum toxin injections. We aimed to establish whether pallidal neurostimulation could improve symptoms in patients not adequately responding to chemodenervation or oral drug treatment.
In this randomised, sham-controlled trial, we recruited patients with cervical dystonia from centres in Germany, Norway, and Austria. Eligible patients (ie, those aged 18–75 years, disease duration ≥3 years, Toronto Western Spasmodic Torticollis Rating Scale [TWSTRS] severity score ≥15 points) were randomly assigned (1:1) to receive active neurostimulation (frequency 180 Hz; pulse width 120 μs; amplitude 0·5 V below adverse event threshold) or sham stimulation (amplitude 0 V) by computer-generated randomisation lists with randomly permuted block lengths stratified by centre. All patients, masked to treatment assignment, were implanted with a deep brain stimulation device and received their assigned treatment for 3 months. Neurostimulation was activated in the sham group at 3 months and outcomes were reassessed in all patients after 6 months of active treatment. Treating physicians were not masked. The primary endpoint was the change in the TWSTRS severity score from baseline to 3 months, assessed by two masked dystonia experts using standardised videos, analysed by intention to treat. This trial is registered with ClinicalTrials.gov, number NCT00148889.
Between Jan 19, 2006, and May 29, 2008, we recruited 62 patients, of whom 32 were randomly assigned to neurostimulation and 30 to sham stimulation. Outcome data were recorded in 60 (97%) patients at 3 months and 56 (90%) patients at 6 months. At 3 months, the reduction in dystonia severity was significantly greater with neurostimulation (–5·1 points [SD 5·1], 95% CI −7·0 to −3·5) than with sham stimulation (−1·3 [2·4], −2·2 to −0·4, p=0·0024; mean between-group difference 3·8 points, 1·8 to 5·8) in the intention-to-treat population. Over the course of the study, 21 adverse events (five serious) were reported in 11 (34%) of 32 patients in the neurostimulation group compared with 20 (11 serious) in nine (30%) of 30 patients in the sham-stimulation group. Serious adverse events were typically related to the implant procedure or the implanted device, and 11 of 16 resolved without sequelae. Dysarthria (in four patients assigned to neurostimulation vs three patients assigned to sham stimulation), involuntary movements (ie, dyskinesia or worsening of dystonia; five vs one), and depression (one vs two) were the most common non-serious adverse events reported during the course of the study.
Pallidal neurostimulation for 3 months is more effective than sham stimulation at reducing symptoms of cervical dystonia. Extended follow-up is needed to ascertain the magnitude and stability of chronic neurostimulation effects before this treatment can be recommended as routine for patients who are not responding to conventional medical therapy.
Medtronic.
Journal Article
Community University Research Agreement
2007
This paper describes the process of engaging the extended Indigenous community within Saskatoon and the surrounding First Nations communities in what would be a first major research project between Indigenous communities and the University of Saskatchewan. A management committee was established comprised of all the major Saskatoon/Saskatchewan Indigenous organisations, such as the Federation of Saskatchewan Indians, Saskatoon Tribal Council, First Nations University of Canada and other community-based groups to ensure that research reflected First Nations and Metis needs. The project called “Bridges and Foundations” awarded some 35 projects close to two million dollars in research funds. The money was awarded through graduate student research bursaries, and community-based projects which highlighted the needs of Indigenous women, youth, students, elders and urban populations. The three research themes included respectful protocol, knowledge creation, and policy development. The research projects, which were largely Indigenous designed and driven, created one of the most extensive research collections over a period of four years and included major data collection on community-based research, Indigenous peoples and Indigenous knowledge systems and protocols. The paper relates the development of the project and speaks about the need for Indigenous peoples to lead their own research as well as the benefits of collaboration. It also highlights several of the research projects including a conference on Indigenous knowledge (2004), a video project describing the community mobilisation process behind Quint Urban Housing Co-operatives,
Journal Article
One Pass Thalamic and Subthalamic Stimulation for Patients with Tremor-Dominant Idiopathic Parkinson Syndrome (OPINION): Protocol for a Randomized, Active-Controlled, Double-Blinded Pilot Trial
2018
Besides fluctuations, therapy refractory tremor is one of the main indications of deep brain stimulation (DBS) in patients with idiopathic Parkinson syndrome (IPS). Although thalamic DBS (ventral intermediate nucleus [Vim] of thalamus) has been shown to reduce tremor in 85-95% of patients, bradykinesia and rigidity often are not well controlled. The dentato-rubro-thalamic tract (DRT) that can directly be targeted with special diffusion tensor magnetic resonance imaging sequences has been shown as an efficient target for thalamic DBS. The subthalamic nucleus (STN) is typically chosen in younger patients as the target for dopamine-responsive motor symptoms. This study investigates a one-path thalamic (Vim/DRT) and subthalamic implantation of DBS electrodes and possibly a combined stimulation strategy for both target regions.
This study investigates a one path thalamic (Vim/DRT) and subthalamic implantation of DBS electrodes and a possibly combined stimulation strategy for both target regions.
This is a randomized, active-controlled, double-blinded (patient- and observer-blinded), monocentric trial with three treatments, three periods and six treatment sequences allocated according to a Williams design. Eighteen patients will undergo one-path thalamic (Vim/DRT) and STN implantation of DBS electrodes. After one month, a double-blinded and randomly-assigned stimulation of the thalamic target (Vim/DRT), the STN and a combined stimulation of both target regions will be performed for a period of three months each. The primary objective is to assess the quality of life obtained by the Parkinson's Disease Questionnaire (39 items) for each stimulation modality. Secondary objectives include tremor reduction (obtained by the Fahn-Tolosa-Marin tremor rating scale, video recordings, the Unified Parkinson's disease rating scale, and by tremor analysis), psychiatric assessment of patients, and to assess the safety of intervention.
At the moment, the recruitment is stopped and 12 patients have been randomized and treated. A futility analysis is being carried out by means of a conditional power analysis.
The approach of the OPINION trial planned to make, for the first time, a direct comparison of the different stimulation conditions (Vim/DRT, compared to STN, compared to Vim/DRT+STN) in a homogeneous patient population and, furthermore, will allow for intraindividual comparison of each condition with the \"quality of life\" outcome parameter. We hypothesize that the combined stimulation of the STN and the thalamic (Vim/DRT) target will be superior with respect to the patients' quality of life as compared to the singular stimulation of the individual target regions. If this holds true, this work might change the standardized treatment described in the previous section.
ClinicalTrials.gov: NCT02288468; https://clinicaltrials.gov/ct2/show/NCT02288468 (Archived by WebCite at http://www.webcitation.org/6wlKnt2pJ); and German Clinical Trials Register: DRKS00007526; https://www.drks.de/drks_ web/navigate.do?navigationId=trial.HTML&TRIAL_ID=DRKS00007526 (Archived by WebCite at http://www.webcitation.org/6wlKyXZZL).
Journal Article
Evaluation of a programming algorithm for deep brain stimulation in dystonia used in a double-blind, sham-controlled multicenter study
by
Steigerwald, Frank
,
Vesper, Jan
,
Kupsch, Andreas
in
Acute effects
,
Algorithms
,
Deep brain stimulation
2019
Programming deep brain stimulation in dystonia is difficult because of the delayed benefits and absence of evidence-based guidelines. Therefore, we evaluated the efficacy of a programming algorithm applied in a double-blind, sham-controlled multicenter study of pallidal deep brain stimulation in dystonia.
A standardized monopolar review to identify the contact with the best acute antidystonic effect was applied in 40 patients, who were then programmed 0.5 V below the adverse effect threshold and maintained on these settings for at least 3 months, if tolerated. If no acute effects were observed, contact selection was based on adverse effects or anatomical criteria. Three-year follow-up data was available for 31 patients, and five-year data for 32 patients. The efficacy of the algorithm was based on changes in motor scores, adverse events, and the need for reprogramming.
The mean (±standard deviation) dystonia motor score decreased by 73 ± 24% at 3 years and 63 ± 38% at 5 years for contacts that exhibited acute improvement of dystonia (
= 17) during the monopolar review. Contacts without acute benefit improved by 58 ± 30% at 3 years (
= 63) and 53 ± 31% at 5 years (
= 59). Interestingly, acute worsening or induction of dystonia/dyskinesia (
= 9) correlated significantly with improvement after 3 years, but not 5 years.
Monopolar review helped to detect the best therapeutic contact in approximately 30% of patients exhibiting acute modulation of dystonic symptoms. Acute improvement, as well as worsening of dystonia, predicted a good long-term outcome, while induction of phosphenes did not correlate with outcome.
ClinicalTrials.gov NCT00142259.
Journal Article
Community research agreement
2007
This paper describes the process of engaging the extended Indigenous community within Saskatoon and the surrounding First Nations communities in what would be a first major research project between Indigenous communities and the University of Saskatchewan. A management committee was established comprised of all the major Saskatoon/ Saskatchewan Indigenous organisations, such as the Federation of Saskatchewan Indians, Saskatoon Tribal Council, First Nations University of Canada and other community-based groups to ensure that research reflected First Nations and Metis needs. The project called 'Bridges and Foundations' awarded some 35 projects close to two million dollars in research funds. The money was awarded through graduate student research bursaries, and community-based projects which highlighted the needs of Indigenous women, youth, students, elders and urban populations. The three research themes included respectful protocol, knowledge creation, and policy development. The research projects, which were largely Indigenous designed and driven, created one of the most extensive research collections over a period of four years and included major data collection on community- based research, Indigenous peoples and Indigenous knowledge systems and protocols. The paper relates the development of the project and speaks about the need for Indigenous peoples to lead their own research as well as the benefits of collaboration. It also highlights several of the research projects including a conference on Indigenous knowledge, a video project describing the community mobilisation process behind Quint Urban Housing Co-operatives. [Author abstract]
Journal Article
Transforming child welfare: interdisciplinary practices, field education, and research : voices from the Prairies
2016
Canada has among the highest rate of children in foster care in the developed world--a national tragedy that has its roots in poverty, residential schooling, and other forms of colonialism. Tackling the \"wicked\" and intransigent problems encountered by social workers, educators, health care workers, and others, Transforming Child Welfare examines systemic issues within the child welfare system, including child abuse, neglect, and FASD. Reflecting on previous strengths, and integrating research and practice, the contributors to this volume provide professionals with best practice solutions that can be applied in different contexts.