Significance: We studied deep brain stimulation effects in two types of dystonia and conclude that different specific connections between the pallidum and thalamus are responsible for optimal treatment effects. Since alternative treatment options for dystonia beyond deep brain stimulation are scarce, our results will be crucial to maximize treatment outcome in this population of patients.

Background: Impulse‐control and related behavioral disorders (ICBDs) significantly impact the lives of Parkinson's disease (PD) patients and caregivers, with lasting consequences if undiagnosed and untreated. While ICBD pathophysiology and risk factors are well‐studied, a standardized severity definition and treatment evidence remain elusive.Objective: This work aimed to establish international expert consensus on ICBD treatment strategies. To comprehensively address diverse treatment availabilities, experts from various continents were included.Methods: From 2021 to 2023, global movement disorders specialists engaged in a Delphi process. A core expert group initiated surveys, involving a larger panel in three iterations, leading to refined severity definitions and treatment pathways.Results: Experts achieved consensus on defining ICBD severity, emphasizing regular PD patient screenings for early detection. General treatment recommendations focused on continuous monitoring, collaboration with significant others, and seeking specialist advice for legal or financial challenges. For mild to severe ICBDs, gradual reduction in dopamine agonists was endorsed, followed by reductions in other PD medications. Second‐line treatment strategies included diverse approaches like reversing the last medication change, cognitive behavior therapy, subthalamic nucleus deep brain stimulation, and specific medications like quetiapine, clozapine, and antidepressants. The panel reached consensus on distinct treatment pathways for punding and dopamine dysregulation syndrome, formulating therapy recommendations. Comprehensive discussions addressed management strategies for the exacerbation of either motor or non‐motor symptoms following the proposed treatments.Conclusion: The consensus offers in‐depth insights into ICBD management, presenting clear severity criteria and expert consensus treatment recommendations. The study highlights the critical need for further research to enhance ICBD management. © 2024 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

Tremor is one of the most common neurological symptoms. Its clinical and neurobiological complexity necessitates novel approaches for granular phenotyping. Instrumented neurophysiological analyses have proven useful, but are highly resource-intensive and lack broad accessibility. In contrast, bedside scores are simple to administer, but lack the granularity to capture subtle but relevant tremor features. We utilise the open-source computer vision pose tracking algorithm Mediapipe to track hands in clinical video recordings and use the resulting time series to compute canonical tremor features. This approach is compared to marker-based 3D motion capture, wrist-worn accelerometry, clinical scoring and a second, specifically trained tremor-specific algorithm in two independent clinical cohorts. These cohorts consisted of 66 patients diagnosed with essential tremor, assessed in different task conditions and states of deep brain stimulation therapy. We find that Mediapipe-derived tremor metrics exhibit high convergent clinical validity to scores (Spearman’s ρ = 0.55–0.86, p≤ .01) as well as an accuracy of up to 2.60 mm (95% CI [−3.13, 8.23]) and ≤0.21 Hz (95% CI [−0.05, 0.46]) for tremor amplitude and frequency measurements, matching gold-standard equipment. Mediapipe, but not the disease-specific algorithm, was capable of analysing videos involving complex configurational changes of the hands. Moreover, it enabled the extraction of tremor features with diagnostic and prognostic relevance, a dimension which conventional tremor scores were unable to provide. Collectively, this demonstrates that current computer vision algorithms can be transformed into an accurate and highly accessible tool for video-based tremor analysis, yielding comparable results to gold standard tremor recordings.

Background: Deep brain stimulation of the subthalamic nucleus (STN‐DBS) is an effective and evidence‐based treatment for idiopathic Parkinson's disease (iPD). A minority of patients does not sufficiently benefit from STN‐DBS.Objective: The predictive validity of the levodopa challenge for individual patients is analyzed.Methods: Data from patients assessed with a preoperative Levodopa‐test and a follow‐up examination (mean ± standard deviation: 9.15 months ±3.39) from Kiel (n = 253), Berlin (n = 78) and Toronto (n = 98) were studied. Insufficient DBS outcome was defined as an overall UPDRS‐III reduction <33% compared to UPDRS‐III in med‐off at baseline or alternatively if the minimal clinically important improvement of 5 points was not reached. Single UPDRS‐items and sub‐scores were dichotomized. Following exploratory analysis, we trained supervised regression‐ and classification models for outcome prediction.Results: Data analysis confirmed significant correlation between the absolute UPDRS‐III reduction during Levodopa challenge and after stimulation. But individual improvement was inaccurately predicted with a large range of up to 30 UPDRS III points. Further analysis identified preoperative UPDRS‐III/med‐off‐scores and preoperative Levodopa‐improvement as most influential factors. The models for UPDRS‐III and sub‐scores improvement achieved comparably low accuracy.Conclusions: With large prediction intervals, the Levodopa challenge use for patient counseling is limited, though remains important for excluding non‐responders to Levodopa. Despite these deficiencies, the current practice of patient selection is highly successful and builds not only on the Levodopa challenge. However, more specific motor tasks and further paraclinical tools for prediction need to be developed.

Healthy adults and neurological patients show unique mobility patterns over the course of their lifespan and disease. Quantifying these mobility patterns could support diagnosing, tracking disease progression and measuring response to treatment. This quantification can be done with wearable technology, such as inertial measurement units (IMUs). Before IMUs can be used to quantify mobility, algorithms need to be developed and validated with age and disease-specific datasets. This study proposes a protocol for a dataset that can be used to develop and validate IMU-based mobility algorithms for healthy adults (18–60 years), healthy older adults (>60 years), and patients with Parkinson’s disease, multiple sclerosis, a symptomatic stroke and chronic low back pain. All participants will be measured simultaneously with IMUs and a 3D optical motion capture system while performing standardized mobility tasks and non-standardized activities of daily living. Specific clinical scales and questionnaires will be collected. This study aims at building the largest dataset for the development and validation of IMU-based mobility algorithms for healthy adults and neurological patients. It is anticipated to provide this dataset for further research use and collaboration, with the ultimate goal to bring IMU-based mobility algorithms as quickly as possible into clinical trials and clinical routine.

Background: The EARLYSTIM trial demonstrated for Parkinson's disease patients with early motor complications that deep brain stimulation of the subthalamic nucleus (STN‐DBS) and best medical treatment (BMT) was superior to BMT alone.Objective: This prospective, ancillary study on EARLYSTIM compared changes in blinded speech intelligibility assessment between STN‐DBS and BMT over 2 years, and secondary outcomes included non‐speech oral movements (maximum phonation time [MPT], oral diadochokinesis), physician‐ and patient‐reported assessments.Methods: STN‐DBS (n = 102) and BMT (n = 99) groups underwent assessmentson/offmedication at baseline and 24 months (in four conditions:on/offmedication, ON/OFF stimulation—for STN‐DBS). Words and sentences were randomly presented to blinded listeners, and speech intelligibility rate was measured. Statistical analyses compared changes between the STN‐DBS and BMT groups from baseline to 24 months.Results: Over the 2‐year period, changes in speech intelligibility and MPT, as well as patient‐reported outcomes, were not different between groups, eitherofforonmedication or OFF or ON stimulation, but most outcomes showed a nonsignificant trend toward worsening in both groups. Change in oral diadochokinesis was significantly different between STN‐DBS and BMT groups,onmedication and OFF STN‐DBS, with patients in the STN‐DBS group performing slightly worse than patients under BMT only. A signal for clinical worsening with STN‐DBS was found for the individual speech item of the Unified Parkinson's Disease Rating Scale, Part III.Conclusion: At this early stage of the patients' disease, STN‐DBS did not result in a consistent deterioration in blinded speech intelligibility assessment and patient‐reported communication, as observed in studies of advanced Parkinson's Disease. © 2022 The Authors.Movement Disorderspublished by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.