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OBJECTIVE To assess use of directional stimulation in Parkinson's disease and essential tremor patients programmed in routine clinical care. MATERIALS AND METHODS Patients with Parkinson's disease or essential tremor implanted at Cleveland Clinic with a directional deep brain stimulation (DBS) system from November 2017 to October 2019 were included in this retrospective case series. Omnidirectional was compared against directional stimulation using therapeutic current strength, therapeutic window percentage, and total electrical energy delivered as outcome variables. RESULTS Fifty-seven Parkinson's disease patients (36 males) were implanted in the subthalamic nucleus (105 leads) and 33 essential tremor patients (19 males) were implanted in the ventral intermediate nucleus of the thalamus (52 leads). Seventy-four percent of patients with subthalamic stimulation (65% of leads) and 79% of patients with thalamic stimulation (79% of leads) were programmed with directional stimulation for their stable settings. Forty-six percent of subthalamic leads and 69% of thalamic leads were programmed on single segment activation. There was no correlation between the length of microelectrode trajectory through the STN and use of directional stimulation. CONCLUSIONS Directional programming was more common than omnidirectional programming. Substantial gains in therapeutic current strength, therapeutic window, and total electrical energy were found in subthalamic and thalamic leads programmed on directional stimulation.

Background The initial COVID-19 pandemic shutdown led to the canceling of elective surgeries throughout most of the USA and Canada. Objective This survey was carried out on behalf of the Parkinson Study Group (PSG) to understand the impact of the shutdown on deep brain stimulation (DBS) practices in North America. Methods A survey was distributed through RedCap® to the members of the PSG Functional Neurosurgical Working Group. Only one member from each site was asked to respond to the survey. Responses were collected from May 15 to June 6, 2020. Results Twenty-three sites participated; 19 (83%) sites were from the USA and 4 (17%) from Canada. Twenty-one sites were academic medical centers. COVID-19 associated DBS restrictions were in place from 4 to 16 weeks. One-third of sites halted preoperative evaluations, while two-thirds of the sites offered limited preoperative evaluations. Institutional policy was the main contributor for the reported practice changes, with 87% of the sites additionally reporting patient-driven surgical delays secondary to pandemic concerns. Pre-post DBS associated management changes affected preoperative assessments 96%; electrode placement 87%; new implantable pulse generator (IPG) placement 83%; IPG replacement 65%; immediate postoperative DBS programming 74%; and routine DBS programming 91%. Conclusion The COVID-19 pandemic related shutdown resulted in DBS practice changes in almost all North American sites who responded to this large survey. Information learned could inform development of future contingency plans to reduce patient delays in care under similar circumstances.

Summary Background People with chronic tetraplegia, due to high-cervical spinal cord injury, can regain limb movements through coordinated electrical stimulation of peripheral muscles and nerves, known as functional electrical stimulation (FES). Users typically command FES systems through other preserved, but unrelated and limited in number, volitional movements (eg, facial muscle activity, head movements, shoulder shrugs). We report the findings of an individual with traumatic high-cervical spinal cord injury who coordinated reaching and grasping movements using his own paralysed arm and hand, reanimated through implanted FES, and commanded using his own cortical signals through an intracortical brain–computer interface (iBCI). Methods We recruited a participant into the BrainGate2 clinical trial, an ongoing study that obtains safety information regarding an intracortical neural interface device, and investigates the feasibility of people with tetraplegia controlling assistive devices using their cortical signals. Surgical procedures were performed at University Hospitals Cleveland Medical Center (Cleveland, OH, USA). Study procedures and data analyses were performed at Case Western Reserve University (Cleveland, OH, USA) and the US Department of Veterans Affairs, Louis Stokes Cleveland Veterans Affairs Medical Center (Cleveland, OH, USA). The study participant was a 53-year-old man with a spinal cord injury (cervical level 4, American Spinal Injury Association Impairment Scale category A). He received two intracortical microelectrode arrays in the hand area of his motor cortex, and 4 months and 9 months later received a total of 36 implanted percutaneous electrodes in his right upper and lower arm to electrically stimulate his hand, elbow, and shoulder muscles. The participant used a motorised mobile arm support for gravitational assistance and to provide humeral abduction and adduction under cortical control. We assessed the participant's ability to cortically command his paralysed arm to perform simple single-joint arm and hand movements and functionally meaningful multi-joint movements. We compared iBCI control of his paralysed arm with that of a virtual three-dimensional arm. This study is registered with ClinicalTrials.gov, number NCT00912041. Findings The intracortical implant occurred on Dec 1, 2014, and we are continuing to study the participant. The last session included in this report was Nov 7, 2016. The point-to-point target acquisition sessions began on Oct 8, 2015 (311 days after implant). The participant successfully cortically commanded single-joint and coordinated multi-joint arm movements for point-to-point target acquisitions (80–100% accuracy), using first a virtual arm and second his own arm animated by FES. Using his paralysed arm, the participant volitionally performed self-paced reaches to drink a mug of coffee (successfully completing 11 of 12 attempts within a single session 463 days after implant) and feed himself (717 days after implant). Interpretation To our knowledge, this is the first report of a combined implanted FES+iBCI neuroprosthesis for restoring both reaching and grasping movements to people with chronic tetraplegia due to spinal cord injury, and represents a major advance, with a clear translational path, for clinically viable neuroprostheses for restoration of reaching and grasping after paralysis. Funding National Institutes of Health, Department of Veterans Affairs.

Objectives Exercise can improve motor function in people with Parkinson's disease but depression reduces the motivation to participate in regular exercise. The aim of this study was to develop a novel Enhanced Exercise Therapy program that uses manual-driven guided exercise and peer-facilitated psychoeducation for individuals with Parkinson's disease and depression. Design 24 week randomized controlled design. Methods Thirty individuals were randomized to Enhanced Exercise Therapy or self-guided therapy, and evaluated at baseline, 12-weeks and at 24-weeks. Enhanced Exercise Therapy included group exercise and group psychoeducation for 12 weeks. Between 13 and 24 weeks, individuals had access to the fitness facility but group sessions were not held. Self-guided therapy included written guidelines for a self-paced exercise program and psychoeducation. Primary outcome measures included the number of exercise sessions and International Physical Activity Questionnaire score. Secondary measures included resting heart rate, supine blood pressure, estimated VO2max and incidence of orthostatic hypotension. Results Twenty four individuals completed the study (80% retention) and both groups attended similar number of exercise sessions. There were no significant changes in cardiovascular fitness measures but there was a significant increase in the amount of physical activity in the Enhanced Exercise Therapy group and a decrease in the self-guided therapy group during the post-intervention period. Conclusions Enhanced Exercise Therapy appears to promote engagement in an exercise program and more physical activity, even after group sessions were concluded in individuals with Parkinson's disease and depression.

Ablation or deep brain stimulation in the internal segment of the globus pallidus (GPi) is an effective therapy for the treatment of Parkinson's disease (PD). Yet many patients receive only partial benefit, including varying levels of improvement across different body regions, which may relate to a differential effect of GPi surgery on the different body regions. Unfortunately, our understanding of the somatotopic organization of human GPi is based on a small number of studies with limited sample sizes, including several based upon only a single recording track or plane. To fully address the three-dimensional somatotopic organization of GPi, we examined the receptive field properties of pallidal neurons in a large cohort of patients undergoing stereotactic surgery. The response of neurons to active and passive movements of the limbs and orofacial structures was determined, using a minimum of three tracks across at least two medial-lateral planes. Neurons (3183) were evaluated from 299 patients, of which 1972 (62%) were modulated by sensorimotor manipulation. Of these, 1767 responded to a single, contralateral body region, with the remaining 205 responding to multiple and/or ipsilateral body regions. Leg-related neurons were found dorsal, medial and anterior to arm-related neurons, while arm-related neurons were dorsal and lateral to orofacial-related neurons. This study provides a more detailed map of individual body regions as well as specific joints within each region and provides a potential explanation for the differential effect of lesions or DBS of the GPi on different body parts in patients undergoing surgical treatment of movement disorders.

Sexually active male rats prefer a sexually receptive female to a nonreceptive female, and partner-preference tests provide one way of studying sexual motivation. Surgical deafferentation of the olfactory bulbs from all the known chemosensory systems of the nasal septum renders rats anosmic. In Experiment 1, we show that, although bulb deafferentation of male rats decreases some aspects of sexual performance, most deafferented males copulate and partner preference is not affected. In Experiment 2, we show that large excitotoxin lesions of the preoptic hypothalamus eliminate copulation, an effect that is correlated with damage to the anterior portions of the medial and lateral preoptic area. Lesions also decrease partner preference, an effect that is correlated (r = 0.82) with damage to a small part of the bed nucleus of the stria terminalis. Most males who do not copulate after hypothalamic lesions show a persistent, albeit reduced, preference for receptive females over nonreceptive females. This preference appears to depend on olfactory ability because bulb deafferentation of lesioned, noncopulating males virtually eliminates partner preference.