Remote levodopa challenge test in Parkinson's disease: Feasibility, reliability, validity and economic value.

BACKGROUND AND PURPOSE: The aim was to demonstrate the feasibility, reliability and validity of an in-home remote levodopa challenge test (LCT), as delivered through an online platform, for patients with Parkinson's disease (PwPD). METHODS: Patients with Parkinson's disease eligible for deep brain stimulation surgery screening were enrolled. Participants sequentially received an in-home remote LCT and an in-hospital standard LCT (separated by 2.71 weeks). A modified Movement Disorder Society Unified Parkinson's Disease Rating Scale Part III omitting rigidity and postural stability items was used in the remote LCT. The reliability of the remote LCT was evaluated using the intraclass correlation coefficient and the concurrent validity was evaluated using the Pearson's correlation coefficient r between the levodopa responsiveness of the remote and standard LCT. RESULTS: Out of 106 PwPD screened, 80 (75.5%) completed both the remote and standard LCT. There was a good reliability (intraclass correlation coefficient 0.81, 95% confidence interval 0.69-0.88) and a strong correlation (r = 0.84, 95% confidence interval 0.77-0.90) between the levodopa responsiveness of the remote and standard LCT. The mean cost for PwPD was estimated to be reduced by 91% by using the remote LCT. CONCLUSION: The remote LCT is feasible, reliable and valid and may reduce healthcare-related costs for PwPD and their caregivers.

Iron and neuromelanin imaging in basal ganglia circuitry in Parkinson's disease with freezing of gait.

OBJECTIVE: This study aimed to examine the structural alterations of the deep gray matter (DGM) in the basal ganglia circuitry of Parkinson's disease (PD) patients with freezing of gait (FOG) using quantitative susceptibility mapping (QSM) and neuromelanin-sensitive magnetic resonance imaging (NM-MRI). METHODS: Twenty-five (25) PD patients with FOG (PD-FOG), 22 PD patients without FOG (PD-nFOG), and 30 age- and sex-matched healthy controls (HCs) underwent 3-dimensional multi-echo gradient recalled echo and NM-MRI scanning. The mean volume and susceptibility of the DGM on QSM data and the relative contrast (NMRC-SNpc) and volume (NMvolume-SNpc) of the substantia nigra pars compacta on NM-MRI were analyzed among groups. A multiple linear regression analysis was performed to explore the associations of FOG severity with MRI measurements and disease stage. RESULTS: The PD-FOG group showed higher susceptibility in the bilateral caudal substantia nigra (SN) compared to the HC group. Both the PD-FOG and PD-nFOG groups showed lower volumes than the HC group in the bilateral caudate and putamen as determined from the QSM data. The NMvolume-SNpc on NM-MRI in the PD-FOG group was significantly lower than in the HC and PD-nFOG groups. Both the PD-FOG and PD-nFOG groups showed significantly decreased NMRC-SNpc. CONCLUSIONS: The PD-FOG patients showed abnormal neostriatum atrophy, increases in iron deposition in the SN, and lower NMvolume-SNpc. The structural alterations of the DGM in the basal ganglia circuits could lead to the abnormal output of the basal ganglia circuit to trigger the FOG in PD patients.

Telemedicine in patients with obsessive-compulsive disorder after deep brain stimulation: a case series.

Background: Patients suffering from refractory obsessive-compulsive disorder (OCD) who have undergone deep brain stimulation (DBS) surgery require repeated in-person programming visits. These sessions could be labor-intensive and may not always be feasible, particularly when in-person hospital visits are restricted. Telemedicine is emerging as a potential supplementary tool for post-operative care. However, its reliability and feasibility still require further validation due to the unconventional methods of interaction. Methods: A study was conducted on three patients with refractory OCD who had undergone DBS. Most of their programming sessions were completed via a remote programming system. These patients were recruited and monitored for a year. Changes in their clinical symptoms were assessed using the Yale-Brown Obsessive-Compulsive Scale-Second Edition (Y-BOCS-II), the Hamilton Anxiety Scale-14 (HAMA), the Hamilton Depression Scale-17 (HAMD), and the Short Form 36 Health Survey Questionnaire (SF-36). The scores from these assessments were reported. Results: At the last follow-up, two out of three patients were identified as responders, with their Y-BOCS-II scores improving by more than 35% (P1: 51%, P3: 42%). These patients also experienced some mood benefits. All patients observed a decrease in travel expenses during the study period. No severe adverse events were reported throughout the study. Conclusion: The group of patients showed improvement in their OCD symptoms within a 1-year follow-up period after DBS surgery, without compromising safety or benefits. This suggests that telemedicine could be a valuable supplementary tool when in-person visits are limited.

Optimizing Deep Brain Stimulation in Essential Tremor: A Randomized Controlled Trial for Target Consideration.

BACKGROUND AND OBJECTIVES: The thalamic ventral intermediate nucleus (VIM) is a well-established target for deep brain stimulation (DBS) in the treatment of essential tremor (ET). Increasing data indicate that the posterior subthalamic area (PSA) may be superior, but high-level evidence is limited. We aimed at further comparing the intraindividual efficacy and side effect profile of PSA vs VIM DBS in ET. METHODS: In this randomized, double-blind, crossover trial, 4-contact DBS leads were bilaterally implanted with single-trajectory covering the VIM and PSA. Patients were randomized postsurgery to 2 groups, receiving VIM stimulation (4-7 months) and then PSA stimulation (8-11 months) or vice versa. The primary end point was the difference in improvement from baseline to the end of the VIM vs PSA DBS period in the total score of the Fahn-Tolosa-Marin Tremor Rating Scale (FTM-TRS). RESULTS: Ten patients with medically refractory ET were enrolled, and 9 completed the study. The difference between reduction of FTM-TRS total score in the PSA vs VIM DBS period was -7.4 (95% CI: -28.5 to 13.7, P = .328). Clinical benefit was achieved at significantly lower stimulation intensity under PSA DBS. Furthermore, PSA DBS provided greater improvement in head tremor subscore of FTM-TRS (PSA vs VIM: -2.2, P = .020) and disease-specific quality of life (PSA vs VIM: -13.8, P = .046) and induced fewer speech (Dysphonia Severity Index score: P = .043; diadochokinetic rate: P = .007; VDI score: P = .005) and gait disturbances compared with VIM DBS. Seven patients remained with PSA DBS after the crossover phase. CONCLUSION: Our study confirms that PSA-DBS is comparable with VIM-DBS in suppressing tremors, superior in improving disease-specific quality of life, and possibly more effective in reducing head tremor.

Globus pallidus internus versus subthalamic nucleus deep brain stimulation for isolated dystonia: A 3-year follow-up.

BACKGROUND AND PURPOSE: Bilateral deep brain stimulation (DBS) surgery targeting the globus pallidus internus (GPi) or the subthalamic nucleus (STN) is widely used in medication-refractory dystonia. However, evidence regarding target selection considering various symptoms remains limited. This study aimed to compare the effectiveness of these two targets in patients with isolated dystonia. METHODS: This retrospective study evaluated 71 consecutive patients (GPi-DBS group, n = 32; STN-DBS group, n = 39) with isolated dystonia. Burke-Fahn-Marsden Dystonia Rating Scale scores and quality of life were evaluated preoperatively and at 1, 6, 12, and 36 months postoperatively. Cognition and mental status were assessed preoperatively and at 36 months postoperatively. RESULTS: Targeting the STN (STN-DBS) yielded effects within 1 month (65% vs. 44%; p = 0.0076) and was superior at 1 year (70% vs. 51%; p = 0.0112) and 3 years (74% vs. 59%; p = 0.0138). For individual symptoms, STN-DBS was preferable for eye involvement (81% vs. 56%; p = 0.0255), whereas targeting the GPi (GPi-DBS) was better for axis symptoms, especially for the trunk (82% vs. 94%; p = 0.015). STN-DBS was also favorable for generalized dystonia at 36-month follow-up (p = 0.04) and required less electrical energy (p < 0.0001). Disability, quality of life, and depression and anxiety measures were also improved. Neither target influenced cognition. CONCLUSIONS: We demonstrated that the GPi and STN are safe and effective targets for isolated dystonia. The STN has the benefits of fast action and low battery consumption, and is superior for ocular dystonia and generalized dystonia, while the GPi is better for trunk involvement. These findings may offer guidance for future DBS target selection for different types of dystonia.

Rescue subthalamic stimulation after unsatisfactory outcome of pallidal stimulation in Parkinson's disease: a case series and review.

Background: Subthalamic nucleus (STN) and globus pallidus interna (GPi) are two main structures primarily targeted by deep brain stimulation (DBS) to treat advanced Parkinson's disease (PD). A subset of cases with unsatisfactory outcomes may benefit from rescue DBS surgery targeting another structure, while these patients' characteristics have not been well described and this phenomenon has not been well reviewed. Methods: This monocentric retrospective study included patients with PD, who underwent rescue STN DBS following an unsatisfactory outcome of the initial bilateral GPi DBS in a retrospective manner. A short review of the current literature was conducted to report the clinical outcome of rescue DBS surgeries. Results: Eight patients were identified, and six of them were included in this study. The rescue STN DBS was performed 19.8 months after the initial GPi DBS. After 8.8 months from the rescue STN DBS, patients showed a significant off-medication improvement by 29.2% in motor symptoms compared to initial GPi DBS. Non-motor symptoms and the health-related quality of life were also significantly improved. Conclusion: Our findings suggest that the rescue STN DBS may improve off-medication motor and non-motor symptoms and quality of life in patients with failure of initial GPi DBS. The short review of the current literature showed that the target switching from GPi to STN was mainly due to poor initial outcomes and was performed by target substitution, whereas the switching from STN to GPi was mainly due to a gradual waning of benefits, long-term axial symptoms, dyskinesia, and dystonia and was performed by target addition.

Rescue procedure for isolated dystonia after the secondary failure of globus pallidus internus deep brain stimulation.

Introduction: Globus pallidus internus (GPi) deep brain stimulation (DBS) is widely used in patients with dystonia. However, 10-20% of patients receive insufficient benefits. The objectives of this study are to evaluate the effectiveness of bilateral subthalamic nucleus (STN) DBS along with unilateral posteroventral pallidotomy (PVP) in patients with dystonia who experienced unsatisfactory GPi-DBS and to address the reported rescue procedures after suboptimal DBS or lesion surgery in dystonia patients. Methods: Six patients with isolated dystonia who had previously undergone bilateral GPi-DBS with suboptimal improvement were included. Standardized assessments of dystonia using the Burke-Fahn-Marsden Dystonia Rating Scale (BFMDRS) and quality of life using SF-36 were evaluated before surgery and 1, 6 months, and last follow-up (LFU) after surgery. STN bilateral OFF (bi-OFF), unilateral ON (uni-ON), and bilateral ON (bi-ON) states were recorded at LFU. Specific items were used to find publications published before 10 April 2022 regarding rescue procedures after suboptimal DBS or lesion surgery in patients with dystonia for reference. Eleven original studies including case reports/series were identified for discussion. Results: Substantial clinical benefits were achieved in all six patients. Significant amelioration was achieved during the 1-month (6.5 ± 7.45; p = 0.0049), 6-month (5.67 ± 6.3; p = 0.0056) follow-ups, and at LFU (4.67 ± 4.72; p = 0.0094) when compared with the baseline (LFU of GPi DBS with on status) (17.33 ± 11.79) assessed by BFMDRS. The percentage of improvement reached 70.6, 74.67, and 77.05%, respectively. At LFU, significant differences were found between the stimulation bi-OFF and uni-ON (11.08 ± 8.38 vs. 9 ± 8.52, p = 0.0191), and between the stimulation bi-OFF and bi-ON (11.08 ± 8.38 vs. 4.67 ± 4.72, p = 0.0164). Trends depicting a better improvement in stimulation bi-ON compared with uni-ON (4.67 ± 4.72 vs. 9 ± 8.52, p = 0.0538) were observed. Conclusion: Our results suggest that bilateral STN-DBS plus unilateral PVP may be an effective rescue procedure for patients with isolated dystonia who experienced suboptimal movement improvement following GPi-DBS. However, given the heterogeneity of patients and the small sample size, these findings should be interpreted with caution.

Effects of High Cervical Spinal Cord Stimulation on Gait Disturbance and Dysarthropneumophonia in Parkinson's Disease and Parkinson Variant of Multiple System Atrophy: A Case Series.

High cervical spinal cord stimulation (HCSCS) was found to have therapeutic effects on Parkinsonian gait disturbance. However, the results were inconsistent and confounded with symptoms of pain. This study aimed to reveal the gait and dysarthric effects of HCSCS in PD (Parkinson's disease) and MSA-P (Parkinson variant of multiple system atrophy) patients without pain. Three PD and five MSA-P patients without painful comorbidities were assessed for gait performance and speech before SCS surgery and at 3- and 6-month follow-up. Stride length and the time spent in the Timed Up-and-Go task showed little change after HCSCS surgery. Overall voice quality (measured by dysphonia severity index) and perceptual speech intelligence improved significantly at 3 months, but improvements slightly diminished at 6 months postoperatively. Change in quality of life (measured by 8-item Parkinson's disease questionnaire) was also notable at 3 months but narrowed over time following HCSCS. In conclusion, HCSCS showed therapeutic effects in improving the dysarthria but not gait disturbance in pain-free PD and MSA-P patients.

Power signatures of habenular neuronal signals in patients with bipolar or unipolar depressive disorders correlate with their disease severity.

The habenula is an epithalamic structure implicated in negative reward mechanisms and plays a downstream modulatory role in regulation of dopaminergic and serotonergic functions. Human and animal studies show its hyperactivity in depression which is curtailed by the antidepressant response of ketamine. Deep brain stimulation of habenula (DBS) for major depression have also shown promising results. However, direct neuronal activity of habenula in human studies have rarely been reported. Here, in a cross-sectional design, we acquired both spontaneous resting state and emotional task-induced neuronal recordings from habenula from treatment resistant depressed patients undergoing DBS surgery. We first characterise the aperiodic component (1/f slope) of the power spectrum, interpreted to signify excitation-inhibition balance, in resting and task state. This aperiodicity for left habenula correlated between rest and task and which was significantly positively correlated with depression severity. Time-frequency responses to the emotional picture viewing task show condition differences in beta and gamma frequencies for left habenula and alpha for right habenula. Notably, alpha activity for right habenula was negatively correlated with depression severity. Overall, from direct habenular recordings, we thus show findings convergent with depression models of aberrant excitatory glutamatergic output of the habenula driving inhibition of monoaminergic systems.

Preoperative Levodopa Response and Deep Brain Stimulation Effects on Motor Outcomes in Parkinson's Disease: A Systematic Review.

BACKGROUND: The up-to-date literature systematically reviewing the predictive value of preoperative levodopa responsiveness after deep brain stimulation (DBS) surgery in motor outcomes in Parkinson's disease (PD) is lacking. OBJECTIVE: To address this issue in patients with PD undergoing bilateral subthalamic nucleus (STN) or globus pallidus interna (GPi) DBS. METHODS: We used the existing PRISMA consensus statement. A comprehensive review of literature from 1993 to May 2021 retrieved from PubMed was conducted. RESULTS: The STN-DBS responsiveness was significantly correlated with the preoperative levodopa responsiveness for the total score of UPDRS-III at both 6- and 12-month follow-ups (P < 0.001). Such correlations were significant after controlling for age at time of surgery and disease duration. The significance of correlation disappeared for longer follow-up times. For the sub-scores of UPDRS-III, a significant correlation between the preoperative levodopa responsiveness and STN DBS responsiveness was observed for rigidity, bradykinesia, and axial symptoms, but not for tremor (P = 0.002, 0.010, 0.007, and 0.542, respectively). The preoperative levodopa responsiveness was significantly correlated with GPi DBS responsiveness for the UPDRS-III total score at a median follow-up of 12 months (P = 0.030). CONCLUSION: The current study confirmed the value of preoperative levodopa responsiveness for prediction of the short-term motor outcome after DBS (for both STN and GPi). The predictive value of levodopa responsiveness in short-term outcomes for respective cardinal motor disabilities and the loss of its predictive value after STN DBS for long-term motor outcomes were highlighted by this study.

Bilateral Habenula deep brain stimulation for treatment-resistant depression: clinical findings and electrophysiological features.

Deep brain stimulation (DBS) of structures in the brain's reward system is a promising therapeutic option for patients with treatment-resistant depression (TRD). Recently, DBS of the habenula (HB) in the brain's anti-reward system has also been reported to alleviate depressive symptoms in patients with TRD or bipolar disorder (BD). In this pilot open-label prospective study, we explored the safety and clinical effectiveness of HB-DBS treatment in seven patients with TRD or BD. Also, local field potentials (LFPs) were recorded from the patients' left and right HB to explore the power and asymmetry of oscillatory activities as putative biomarkers of the underlying disease state. At 1-month follow-up (FU), depression and anxiety symptoms were both reduced by 49% (n = 7) along with substantial improvements in patients' health status, functional impairment, and quality of life. Although the dropout rate was high and large variability in clinical response existed, clinical improvements were generally maintained throughout the study [56%, 46%, and 64% reduction for depression and 61%, 48%, and 70% reduction for anxiety at 3-month FU (n = 5), 6-month FU (n = 5), and 12-month FU (n = 3), respectively]. After HB-DBS surgery, sustained improvements in mania symptoms were found in two patients who presented with mild hypomania at baseline. Another patient, however, experienced an acute manic episode 2 months after surgery that required hospitalization. Additionally, weaker and more symmetrical HB LFP oscillatory activities were associated with more severe depression and anxiety symptoms at baseline, in keeping with the hypothesis that HB dysfunction contributes to MDD pathophysiology. These preliminary findings indicate that HB-DBS may offer a valuable treatment option for depressive symptoms in patients who suffer from TRD or BD. Larger and well-controlled studies are warranted to examine the safety and efficacy of HB-DBS for treatment-refractory mood disorders in a more rigorous fashion.

Bilateral globus pallidus interna deep brain stimulation in Parkinson's disease: Therapeutic effects and motor outcomes prediction in a short-term follow up.

Objective: We aimed to compare the motor effect of bilateral globus pallidus interna (GPi) deep brain stimulation (DBS) on motor subtypes of Parkinson's disease (PD) patients and identify preoperative predictive factors of short-term motor outcome. Methods: We retrospectively investigated bilateral GPi DBS clinical outcomes in 55 PD patients in 1 year follow up. Motor outcome was measured by the Movement Disorder Society Unified Parkinson's Disease Rating Scale (MDS-UPDRS) part III before and 1 year after surgery. Clinical outcomes were compared among different motor subtypes. Preoperative predictors of motor outcome were assessed by performing univariate and multivariate linear regression and logistic regression analyses. Results: At 1 year following implantation, GPi DBS significantly improved the off-medication MDS-UPDRS III scores in all motor subtype cohorts, with prominent improvement in tremor. No significant difference of postoperative motor symptoms changes was found except greater tremor improvement achieved in both the tremor-dominant (TD) and indeterminate (IND) patients compared to the postural instability and gait difficulty (PIGD) patients. High percentage of PIGD patients were weak responders to DBS. Better levodopa responsiveness and more severe tremor predicted greater overall improvement of motor function in the entire cohort. Similarly, both levodopa responsiveness and tremor improvement were confirmed as predictors for motor improvement in PIGD patients. Conclusion: Bilateral GPi DBS could effectively improve motor outcomes in PD patients regardless of motor subtypes. Both TD and IND patients obtained larger tremor improvement. The intensity of levodopa responsiveness and the severity of tremor could serve as predictors of motor improvement 1 year after GPi DBS.

Remote video-based outcome measures of patients with Parkinson's disease after deep brain stimulation using smartphones: a pilot study.

OBJECTIVE: To provide better postoperative healthcare for patients with Parkinson's disease (PD) who received deep brain stimulation (DBS) surgery and to allow surgeons improved tracking of surgical outcomes, the authors sought to examine the applicability and feasibility of remote assessment using smartphones. METHODS: A disease management mobile application specifically for PD was used to perform the remote assessment of patients with PD who underwent DBS. Connection with patients was first established via a phone call or a social application, and instructions for completing the remote assessment were delivered. During the video-based virtual meeting, three nonmotor assessment scales measuring the quality of life and mental state, and a modified version of the Movement Disorder Society-sponsored revision of the Unified Parkinson's Disease Rating Scale, part III (MDS-UPDRS III) measuring motor abilities were evaluated. After the assessment, a report and the satisfaction questionnaire were sent to the patient. RESULTS: Overall, 22 patients were recruited over a 4-week period. Among those, 18 patients completed the assessment on the mobile application. The mean duration was 41.3 minutes for video assessment and 17.5 minutes for nonmotor assessment via telephone. The mean estimated cost was 427.68 Chinese yuan (CNY) for an in-person visit and 20.91 CNY for a virtual visit (p < 0.001). The mean time estimate for an in-person visit was 5.51 hours and 0.68 hours for a virtual visit (p = 0.002). All patients reported satisfaction (77.78% very satisfied and 22.22% satisfied) with the virtual visit and were specifically impressed by the professionalism and great attitude of the physician assistant. The majority of patients agreed that the evaluation time was reasonable (50% totally agree, 44.44% agree, and 5.56% neither agree nor disagree) and all patients expressed interest in future virtual visits (61.11% very willingly and 38.89% willingly). No adverse events were observed during the virtual visit. CONCLUSIONS: Innovation in remote assessment technologies was highly feasible for its transforming power in the clinical management of patients with PD who underwent DBS and research. Video-based remote assessment offered considerable time and resource reduction for both patients and doctors. It also increased safety and was a well-accepted, favored tool. Finally, the results of this study have shown there is potential to combine remote assessment tools with real-life clinical visits and other telemedical technologies to collectively benefit the postoperative healthcare of patients with PD undergoing DBS.

Recharging Difficulty With Pulse Generator After Deep Brain Stimulation: A Case Series of Five Patients.

Background: Deep brain stimulation (DBS) is a well-established treatment for a variety of movement disorders. Rechargeable cell technology was introduced to pulse generator more than 10 years ago and brought great benefits to patients. However, with the widespread use of rechargeable implanted pulse generators (r-IPGs), a new hardware complication, when charging the r-IPG has been difficult, was encountered. Objective: The aims of this study were to report five cases confronted with r-IPG charging difficulty postoperatively and to explore the predisposing factors and treatment strategies for this rare complication. Methods: We retrospectively reviewed our DBS patient database for those who were implanted with r-IPGs. From 2012, we identified a total of 1,226 patients, with five of them experiencing charging difficulties after surgery. Detailed patient profiles and clinical procedures were scrutinized and reviewed. Results: All the charging problems were resolved by reoperation. Cases 1 and 2 required their r-IPGs to be anchored to the muscle and fascia. Cases 3 and 4 had their r-IPGs inserted in the wrong orientation at the initial surgery, which was resolved by turning around the r-IPGs at the revision surgery. Case 5, in which we propose that the thick subcutaneous fat layer blocked the connection between the r-IPG and the recharger, required a second operation to reposition the r-IPG in a shallow layer underneath the skin. For all cases, the charging problems were resolved without reoccurrences to date. Conclusion: Our case series indicates a novel hardware complication of DBS surgery, which had been rarely reported before. In this preliminary study, we describe several underlying causes of this complication and treatment methods.

Predicting Motor Outcome of Subthalamic Nucleus Deep Brain Stimulation for Parkinson's Disease Using Quantitative Susceptibility Mapping and Radiomics: A Pilot Study.

BACKGROUND: Emerging evidence indicates that iron distribution is heterogeneous within the substantia nigra (SN) and it may reflect patient-specific trait of Parkinson's Disease (PD). We assume it could account for variability in motor outcome of subthalamic nucleus deep brain stimulation (STN-DBS) in PD. OBJECTIVE: To investigate whether SN susceptibility features derived from radiomics with machine learning (RA-ML) can predict motor outcome of STN-DBS in PD. METHODS: Thirty-three PD patients underwent bilateral STN-DBS were recruited. The bilateral SN were segmented based on preoperative quantitative susceptibility mapping to extract susceptibility features using RA-ML. MDS-UPDRS III scores were recorded 1-3 days before and 6 months after STN-DBS surgery. Finally, we constructed three predictive models using logistic regression analyses: (1) the RA-ML model based on radiomics features, (2) the RA-ML+LCT (levodopa challenge test) response model which combined radiomics features with preoperative LCT response, (3) the LCT response model alone. RESULTS: For the predictive performances of global motor outcome, the RA-ML model had 82% accuracy (AUC = 0.85), while the RA-ML+LCT response model had 74% accuracy (AUC = 0.83), and the LCT response model alone had 58% accuracy (AUC = 0.55). For the predictive performance of rigidity outcome, the accuracy of the RA-ML model was 80% (AUC = 0.85), superior to those of the RA-ML+LCT response model (76% accuracy, AUC = 0.82), and the LCT response model alone (58% accuracy, AUC = 0.42). CONCLUSION: Our findings demonstrated that SN susceptibility features from radiomics could predict global motor and rigidity outcomes of STN-DBS in PD. This RA-ML predictive model might provide a novel approach to counsel candidates for STN-DBS.

Deep Brain Stimulation-Induced Transient Effects in the Habenula.

The habenula, located in the epithalamus, has been implicated in various psychiatric disorders including mood disorders and schizophrenia. This study explored the transient effects of deep brain stimulation in the habenula. Each of the four patients (two with bipolar disorder and two with schizophrenia) was tested with eight deep brain stimulation contacts. Patients were examined via transient electrical stimulation 1 month after deep brain stimulation surgery. The pulse width was 60 µs and the voltage ranged from 0 V to a maximum of 10 V, increasing in increments of 1 V. Each patient received stimulation at two frequencies, 60 and 135 Hz. A total of 221 out of 385 active trials elicited stimulation-induced effects. The three most common transient effects were numbness, heart rate changes, and pain. The incidence of numbness, heart rate changes, pain, and involuntary movements increased with the increase in stimulation voltage. Through contralateral stimulation, numbness was triggered in all parts of the body except the scalp. The obtained stimulus-response maps suggested a possible somatosensory organization of the habenula.

Fixed-Life or Rechargeable Battery for Deep Brain Stimulation: Preference and Satisfaction in Chinese Patients With Parkinson's Disease.

Introduction: DBS is a widely used therapy for PD. There is now a choice between fixed-life implantable pulse generators (IPGs) and rechargeable IPGs, each having advantages and disadvantages. This study aimed to evaluate the preference and satisfaction of Chinese patients with Parkinson's disease (PD) who were treated with deep brain stimulation (DBS). Materials and Methods: Two hundred and twenty PD patients were treated with DBS and completed a self-reported questionnaire to assess their long-term satisfaction and experience with the type of battery they had chosen and the key factors affecting these choices. The survey was performed online and double-checked for completeness and accuracy. Results: The median value of the postoperative duration was 18 months. The most popular way for patients to learn about DBS surgery was through media (79/220, 35.9%) including the Internet and television programs. In total, 87.3% of the DBS used rechargeable IPGs (r-IPG). The choice between rechargeable and non-rechargeable IPGs was significantly associated with affordability ( χ ( 1 ) 2 = 19.13, p < 0.001). Interestingly, the feature of remote programming significantly affected patients' choices between domestic and imported brands ( χ ( 1 ) 2 = 16.81, p < 0.001). 87.7% of the patients were satisfied with the stimulating effects as well as the implanted device itself. 40.6% of the patients with r-IPGs felt confident handling devices within 1 week after discharge. More than half of the patients checked their batteries every week. The mean interval for battery recharge was 4.3 days. 57.8% of the patients spent around 1 h recharging, and 71.4% of them recharged the battery independently. Conclusions: Most patients were satisfied with their choice of IPGs. The patients' economic status and the remote programming function of the device were the two most critical factors in their decision. The skill of recharging the IPG was easy to master for most patients.

Deep Brain Stimulation for Parkinson's Disease During the COVID-19 Pandemic: Patient Perspective.

BACKGROUND: Public health guidelines have recommended that elective medical procedures, including deep brain stimulation (DBS) surgery for Parkinson's disease (PD), should not be scheduled during the coronavirus (COVID-19) pandemic to prevent further virus spread and overload on health care systems. However, delaying DBS surgery for PD may not be in the best interest of individual patients and is not called for in regions where virus spread is under control and inpatient facilities are not overloaded. METHODS: We administered a newly developed phone questionnaire to 20 consecutive patients with PD who received DBS surgery in Ruijin Hospital in Shanghai during the COVID-19 pandemic. The questionnaire was designed to gather the patients' experiences and perceptions on the impact of COVID-19 on their everyday activities and access to medical care. RESULTS: Most of the patients felt confident about the preventive measures taken by the government and hospitals, and they have changed their daily living activities accordingly. Moreover, a large majority of patients felt confident obtaining access to regular and COVID-19-related health care services if needed. Routine clinical referral, sense of security in the hospital during the outbreak, and poor control of PD symptoms were the three main reasons given by patients for seeking DBS surgery during the COVID-19 pandemic. CONCLUSION: The COVID-19 pandemic has considerably impacted medical care and patients' lives but elective procedures, such as DBS surgery for PD, do not need to be rescheduled when the health care system is not overloaded and adequate public health regulations are in place.

Revisiting the L-Dopa Response as a Predictor of Motor Outcomes After Deep Brain Stimulation in Parkinson's Disease.

Objective: To investigate the correlation between preoperative response to the L-dopa challenge test and efficacy of deep brain stimulation (DBS) on motor function in Parkinson's disease (PD). Methods: We retrospectively reviewed the data of 38 patients with idiopathic PD who underwent DBS surgery with a median follow-up duration of 7 months. Twenty underwent bilateral globus pallidus interna (GPi) DBS, and 18 underwent bilateral subthalamic nucleus (STN) DBS. The Movement Disorder Society Unified Parkinson Disease Rating Scale-Motor Part (MDS UPDRS-III) was assessed before surgery and at the last follow-up in different medication and stimulation conditions, respectively. Results: Pearson's correlation analysis revealed a positive correlation between preoperative L-dopa challenge responsiveness and GPi-DBS responsiveness on the total score (R 2 = 0.283, p = 0.016) but not on the non-tremor total score (R 2 = 0.158, p = 0.083) of MDS UPDRS-III. Such correlation remained significant (R 2' = 0.332, p = 0.010) after controlling for age at the time of surgery as confounding factor by partial correlation analysis. The preoperative L-dopa challenge responsiveness was significantly correlated with the tremor-controlling outcome of GPi-DBS (R 2 = 0.390, p = 0.003). In contrast, we found a positive correlation between preoperative L-dopa challenge responsiveness and STN-DBS responsiveness on the non-tremor total score (R 2 = 0.290, p = 0.021), but not on the total score (R 2 = 0.130, p = 0.141) of MDS UPDRS-III. The partial correlation analysis further demonstrated that the predictive value of preoperative L-dopa challenge responsiveness on the non-tremor motor outcome of STN-DBS was eliminated (R 2' = 0.120, p = 0.174) after controlling for age at the time of surgery as confounding factor. Interpretation: The short-term predictive value of preoperative response to the L-dopa challenge test for the motor outcome of GPi-DBS in PD was systematically described. Our findings suggest: (1) a solid therapeutic effect of GPi-DBS in treating L-dopa-responsive tremors; (2) a negative effect of age at the time of surgery on motor outcomes of STN-DBS, (3) a possible preference of STN- to GPi-DBS in L-dopa-resistant tremor control, and (4) a possible preference of GPi- to STN-DBS in elderly PD patients who have a satisfactory dopamine response.

Subthalamic Stimulation for Camptocormia in Parkinson's Disease: Association of Volume of Tissue Activated and Structural Connectivity with Clinical Effectiveness.

BACKGROUND: Deep brain stimulation of the subthalamic nucleus (STN-DBS) has been reported to be effective for camptocormia in Parkinson's disease (PD). However, the association between clinical effectiveness and the stimulated volumes or structural connectivity remains unexplored. OBJECTIVE: To investigate the effectiveness of STN-DBS for treating camptocormia in PD and its association with volumes of tissue activated (VTA) and structural connectivity. METHODS: We reviewed video recordings of patients who had undergone STN-DBS. The total and upper camptocormia (TCC and UCC) angles were measured to quantify changes in camptocormia. The Movement Disorders Society Unified Parkinson's Disease Rating Scale III (MDS-UPDRS III) was used to assess motor symptoms. Pre- and postoperative brain images were collected for modeling volume of VTA and structural connectivity using Lead-DBS software. RESULTS: Participants included 36 patients with PD (8 with TCC-camptocormia and 2 with UCC-camptocormia) treated with bilateral STN-DBS. After surgery, patients showed a significant improvement in postural alignment at follow-up (mean follow-up duration: 6.0±2.2 months). In the entire sample, higher structural connectivity to the right supplementary motor area (SMA) and right lateral premotor cortex along the dorsal plane (PMd) was associated with larger postsurgical improvements in axial signs and TCC angles after stimulation was turned on. In patients diagnosed with camptocormia, larger improvement in camptocormia angles after STN-DBS was associated with a larger VTA overlap with STN (R = 0.75, p = 0.032). CONCLUSION: This study suggests that both VTA overlap with STN and structural connectivity to cortical motor regions are associated with the effectiveness of STN-DBS for managing camptocormia in PD.