Investigation of the nonmotor symptoms in patients with STN-DBS therapy in comparison with those without STN-DBS.

The impact of STN-DBS on NMS remains rather as an underestimated topic. Besides, the significance of NMSs in QOL indexes of PD subjects with STN-DBS is unknown. We primarily aimed to evaluate the NMSs and their significance in QOL indexes in PD subjects comparatively with and without STN-DBS therapy. We enrolled all consecutive PD subjects with and without STN-DBS who applied to our movement disorders outpatient clinics between January/2023 and September/2023. We performed comprehensive assessments of the motor and nonmotor features including the clinical scales of Movement Disorder Society-sponsored revision of the MDS-UPDRS, NMSS, HAM-A, HAM-D, and the PDQ-39. Overall, 48 PD subjects with STN-DBS and 161 without STN-DBS treatment were included. The comparative analyses revealed that the sub-scores of the MDS-UPDRS-2, -3 and -4 were higher in the STN-DBS group. However, the MDS-UDPRS-1 and the total scores of the NMSS were similar between groups. Among eight subitems of the NMSS, only, the sub scores of the mood/cognition and the gastrointestinal tract differed. Remarkably, the significant correlations between the scores of the QOL and the NMSS scores in the STN-DBS (-) group, did not persist within the STN-DBS group. Remarkably, the correlations between the NMSS and PQQ-39 disappeared for most of the sub scores within the STN-DBS group. We found indirect evidence regarding the benefit of STN-DBS therapy on NMSs in our cross-sectional study. Besides, we found weaker impact of NMSs in QOL indexes in PD subjects with STN-DBS therapy.

Interplay between speech and gait variables in Parkinson's disease patients treated with subthalamic nucleus deep brain stimulation: A long-term instrumental assessment.

OBJECTIVE: To evaluate correlations between speech and gait parameters in the long term and under different medication and subthalamic nucleus deep brain stimulation (STN-DBS) conditions in a cohort of advanced Parkinson's disease (PD) patients. METHODS: This observational study included consecutive PD patients treated with bilateral STN-DBS. Axial symptoms were evaluated using a standardized clinical-instrumental approach. Speech and gait were assessed by perceptual and acoustic analyses and by the instrumented Timed Up and Go (iTUG) test, respectively. Disease motor severity was evaluated with the total score and subscores of the Unified Parkinson's Disease Rating Scale (UPDRS) Part III. Different stimulation and drug treatment conditions were assessed: on-stimulation/off-medication, off-stimulation/off-medication, and on-stimulation/on-medication. RESULTS: Twenty-five PD patients with a 5-year median follow-up after surgery (range 3-7 years) were included (18 males; disease duration at surgery: 10.44 [SD 4.62] years; age at surgery: 58.40 [SD 5.73] years). In the off-stimulation/off-medication and on-stimulation/on-medication conditions, patients who spoke louder had also the greater acceleration of the trunk during gait; whereas in the on-stimulation/on-medication condition only, patients with the poorer voice quality were also the worst to perform the sit to stand and gait phases of the iTUG. Conversely, patients with the higher speech rate performed well in the turning and walking phases of the iTUG. CONCLUSIONS: This study underlines the presence of different correlations between treatment effects of speech and gait parameters in PD patients treated with bilateral STN-DBS. This may allow us to better understand the common pathophysiological basis of these alterations and to develop a more specific and tailored rehabilitation approach for axial signs after surgery.

Relationship between serum uric acid levels and the outcome of STN-DBS in Parkinson's disease.

BACKGROUND: Uric acid is a natural antioxidant and it has been shown that low levels of uric acid may be a risk factor for the development of Parkinson's disease. We aimed to investigate the relationship between uric acid and improvement of motor symptoms in patients with Parkinson's disease after subthalamic nucleus deep brain stimulation. METHODS: We analyzed the correlation between serum uric acid levels in 64 patients with Parkinson's disease and the rate of improvement of motor symptoms 2 years after subthalamic nucleus deep brain stimulation. RESULTS: A non-linear correlation was observed between uric acid levels and the rate of motor symptom improvement after subthalamic nucleus deep brain stimulation, during both the drug-off and drug-on periods. CONCLUSIONS: Uric acid is positively associated with the rate of motor symptom improvement in subthalamic nucleus deep brain stimulation within a certain range.

Pre-operative cognitive burden as predictor of motor outcome following bilateral subthalamic nucleus deep brain stimulation in Parkinson's disease.

INTRODUCTION: The interrelationship between neurocognitive impairments and motor functions was observed in patients with advanced Parkinson's disease (PD). This study was conducted to identify pre-operative neurocognitive and clinical predictors of short-term motor outcome following subthalamic nucleus deep brain stimulation (STN-DBS). METHODS: All consecutive PD patients who were eligible for bilateral STN-DBS from 2009 to 2019 were evaluated before and at 1 year following surgery. Standard motor evaluation and neurocognitive tests including global cognition, memory, executive functions (attention and category fluency), confrontational speech, visuospatial abilities, and mood were conducted at baseline. The post-operative STN-DBS effects were assessed at 1 year following the surgery. Multiple regression analysis was applied to identify baseline independent predictors of post-operative STN-DBS effect. RESULTS: A total of 82 patients were analyzed. It was found that younger age at operation, higher levodopa responsiveness at baseline based on UPDRS-III total score, and better baseline verbal delayed memory and category fluency predicted post-operative motor outcome at 1 year following STN-DBS (F = 9.639, p < 0.001, R2 = .340). CONCLUSION: Our findings demonstrated the role of baseline cognitive burden, especially cognitive processes related to frontostriatal circuits, was significant clinical predictors of short-term motor outcomes following STN-DBS. Profile analysis of neurocognitive functions at baseline is recommended.

Investigating the effects of subthalamic Nucleus-Deep brain stimulation on the voice quality.

Introduction: Deep brain stimulation (DBS) is a standard surgical treatment method which is generally applied to subthalamic nucleus in Parkinson's patients in cases where medical treatment is insufficient in treating the motor symptoms. It is known that Subthalamic Nucleus Deep Brain Stimulation (STN-DBS) treats many motor symptoms. However, the results of studies on speech and voice vary. The aim of the study is analysing the effect of STN-DBS on the characteristics of voice.Materials/methods: A total of 12 patients, (8 male-4 female) with an age average of 58.8 ± 9.6, who have been applied DBS surgery on STN included in the study. The voice recordings of the patients have been done prior to surgery and 6 months after the surgery. The evaluation of voice has been carried out through the instrumental method. The patients' voice recordings of the /a,e,i/ vowels have been done. The obtained recordings were evaluated by the Praat programme and the effects on jhitter, shimmer, fundamental frequency (F0) and noise harmonic rate (NHR) were analysed.Results: Numerical values of F0 of all female participants have been decreased for all of the vowels postoperatively. In the females; jhitter and fraction parameters were found to be significantly different (0.056 and 0.017, perspectively) for the vowel /e/. In addition, p values in the shimmer for vowels /e,i/ were thought to be clinically significant (.087, .079 and .076) respectively. All these changes in second measurements were found to indicate worsening vocal quality after the DBS in females. In males, there is not any significant difference observed between two measures in any of the parameters of any vowels.Conclusions: Acoustic voice quality deteriorated after STN-DBS predominantly for females however this deterioration was not prominent audio-perceptually. This finding commented as a result of the fact that that voice quality deviance of the participants was not severe.

Mechanisms of action underlying the efficacy of deep brain stimulation of the subthalamic nucleus in Parkinson's disease: central role of disease severity.

Despite consensus on some neurophysiological hallmarks of the Parkinsonian state (such as beta) band increase) a single mechanism is unlikely to explain the efficacy of deep brain stimulation (DBS) of the subthalamic nucleus (STN). Most experimental evidence to date correlates with an extreme degree of nigral neurodegeneration and not with different stages of PD progression. It seems inappropriate to combine substantially different patients - newly diagnosed, early fluctuators or advanced dyskinetic individuals - within the same group. An efficacious STN-DBS imposes a new activity pattern within brain circuits, favouring alpha- and gamma-like neuronal discharge, and restores the thalamo-cortical transmission pathway through axonal activation. In addition, stimulation via the dorsal contacts of the macro-electrode may affect cortical activation antidromically. However, basal ganglia (BG) modulation remains cardinal for 'OFF'-'ON' transition (as revealed by cGMP increase occurring during STN-DBS in the substantia nigra pars reticulata and internal globus pallidus). New research promises to clarify to what extent STN-DBS restores striato-centric bidirectional plasticity, and whether non-neuronal cellular actions (microglia, neurovascular) play a part. Future studies will assess whether extremely anticipated DBS or lesioning in selected patients are capable of providing neuroprotection to the synuclein-mediated alterations of synaptic efficiency. This review addresses these open issues through the specific mechanisms prevailing in a given disease stage. In patients undergoing early protocol, alteration in endogenous transmitters and recovery of plasticity are concurrent players. In advanced stages, re-modulation of endogenous band frequencies, disruption of pathological pattern and/or antidromic cortical activation are, likely, the prominent modes.

Subthalamic Nucleus Deep Brain Stimulation Employs trkB Signaling for Neuroprotection and Functional Restoration.

Deep brain stimulation (DBS) of the subthalamic nucleus (STN) is the most common neurosurgical treatment for Parkinson's disease motor symptoms. In preclinical models, STN DBS provides neuroprotection for substantia nigra (SN) dopamine neurons and increases BDNF in the nigrostriatal system and primary motor cortex. However, whether BDNF signaling in the SN participates in the neuroprotective effects of DBS remains unknown. We demonstrate that STN DBS in male rats activates signaling downstream of tropomyosin receptor kinase type B (trkB), namely, phosphorylation of Akt and ribosomal protein S6, in SN neurons. Long-term trkB blockade abolished STN DBS-mediated neuroprotection of SN neurons following progressive 6-hydroxydopamine lesion and was associated with decreased phosphorylated ribosomal protein S6 immunoreactivity. Acute trkB blockade in rats with stable nigrostriatal denervation attenuated the forelimb akinesia improvement normally induced by STN DBS. These results suggest that STN DBS increases BDNF-trkB signaling to contribute to the neuroprotective and symptomatic efficacy of STN DBS.SIGNIFICANCE STATEMENT Subthalamic nucleus deep brain stimulation (STN DBS) is increasingly used in mid- to late-stage Parkinson's disease (PD) but with an incomplete knowledge of its molecular mechanisms. STN DBS is neuroprotective against neurotoxicants in animal models and increases BDNF. This study is the first to show that BDNF signaling through the cognate tropomyosin receptor kinase type B (trkB) receptor occurs in substantia nigra pars compacta neurons and is required for neuroprotection. In addition, blockade of trkB unexpectedly reduced the functional benefit of STN DBS on a short timescale that is inconsistent with canonical trkB signaling pathways, suggesting a noncanonical role for trkB in STN DBS-mediated behavioral effects. Together, these data implicate trkB signaling in the symptomatic efficacy and disease-modifying potential of STN DBS.

Bilateral deep brain stimulation of the subthalamic nucleus increases pointing error during memory-guided sequential reaching.

Deep brain stimulation of the subthalamic nucleus (STN DBS) significantly improves clinical motor symptoms, as well as intensive aspects of movement like velocity and amplitude in patients with Parkinson's disease (PD). However, the effects of bilateral STN DBS on integrative and coordinative aspects of motor control are equivocal. The aim of this study was to investigate the effects of bilateral STN DBS on integrative and coordinative aspects of movement using a memory-guided sequential reaching task. The primary outcomes were eye and finger velocity and end-point error. We expected that bilateral STN DBS would increase reaching velocity. More importantly, we hypothesized that bilateral STN DBS would increase eye and finger end-point error and this would not simply be the result of a speed accuracy trade-off. Ten patients with PD and bilaterally implanted subthalamic stimulators performed a memory-guided sequential reaching task under four stimulator conditions (DBS-OFF, DBS-LEFT, DBS-RIGHT, and DBS-BILATERAL) over 4 days. DBS-BILATERAL significantly increased eye velocity compared to DBS-OFF, DBS-LEFT, and DBS-RIGHT. It also increased finger velocity compared to DBS-OFF and DBS-RIGHT. DBS-BILATERAL did not change eye end-point error. The novel finding was that DBS-BILATERAL increased finger end-point error compared to DBS-OFF, DBS-LEFT, and DBS-RIGHT even after adjusting for differences in velocity. We conclude that bilateral STN DBS may facilitate basal ganglia-cortical networks that underlie intensive aspects of movement like velocity, but it may disrupt selective basal ganglia-cortical networks that underlie certain integrative and coordinative aspects of movement such as spatial accuracy.

Pathological gambling in Parkinson's disease: what are the risk factors and what is the role of impulsivity?

The incidence of pathological gambling in Parkinson's patients is significantly greater than in the general population. A correlation has been observed between dopamine agonist medication and the development of pathological gambling. However, scientists conjecture that the affected patients have underlying risk factors. Studies analysing Parkinson's patients have detected that patients who developed pathological gambling are younger, score higher on novelty-seeking tests, are more impulsive and are more likely to have a personal or family history of alcohol addiction. In addition, some genetic variations have been associated with the susceptibility of developing pathological gambling, which include mutations of DRD3, 5-HTTLPR and GRIN2B. Studies focusing on neurofunctional discrepancies between Parkinson's patients with and without pathological gambling have found increased functional activation and dopamine release in regions associated with the mesolimbic reward system. Furthermore, there is also evidence showing increased processing of reward and decreased activation elicited by punishment, suggesting altered learning processes. Furthermore, the role of deep brain stimulation of the nucleus subthalamicus (STN DBS) is controversial. In most Parkinson's patients, pathological gambling resolved after the initiation of the STN DBS, which might be explained by discontinuation or decrease in dopamine agonist medication. However, it has been also shown that some patients are more impulsive while the STN DBS is activated. These differences may depend on the DBS localization in the more limbic or motor part of the STN and their regulative effects on impulsivity. Further research is needed to clarify susceptibility factors for the development of pathological gambling in Parkinson's patients.

The effects of unilateral versus bilateral subthalamic nucleus deep brain stimulation on prosaccades and antisaccades in Parkinson's disease.

Unilateral deep brain stimulation (DBS) of the subthalamic nucleus (STN) in patients with Parkinson's disease improves skeletomotor function assessed clinically, and bilateral STN DBS improves motor function to a significantly greater extent. It is unknown whether unilateral STN DBS improves oculomotor function and whether bilateral STN DBS improves it to a greater extent. Further, it has also been shown that bilateral, but not unilateral, STN DBS is associated with some impaired cognitive-motor functions. The current study compared the effect of unilateral and bilateral STN DBS on sensorimotor and cognitive aspects of oculomotor control. Patients performed prosaccade and antisaccade tasks during no stimulation, unilateral stimulation, and bilateral stimulation. There were three sets of findings. First, for the prosaccade task, unilateral STN DBS had no effect on prosaccade latency and it reduced prosaccade gain; bilateral STN DBS reduced prosaccade latency and increased prosaccade gain. Second, for the antisaccade task, neither unilateral nor bilateral stimulation had an effect on antisaccade latency, unilateral STN DBS increased antisaccade gain, and bilateral STN DBS increased antisaccade gain to a greater extent. Third, bilateral STN DBS induced an increase in prosaccade errors in the antisaccade task. These findings suggest that while bilateral STN DBS benefits spatiotemporal aspects of oculomotor control, it may not be as beneficial for more complex cognitive aspects of oculomotor control. Our findings are discussed considering the strategic role the STN plays in modulating information in the basal ganglia oculomotor circuit.

Postoperative symptoms of psychosis after deep brain stimulation in patients with Parkinson's disease.

OBJECT: Cases of postoperative psychosis in Parkinson's disease patients receiving deep brain stimulation (DBS) treatment have previously been published. However, the magnitude of symptom incidence and the clinical risk factors are currently unknown. This retrospective study sheds light on these issues by investigating psychosis in a group of 128 Parkinson's disease patients who received DBS implants. METHODS: A retrospective chart review was performed to obtain surgery dates, follow-up clinic visit dates, and associated stimulation parameter settings (contacts in use and the polarity of each along with stimulation voltage, frequency, and pulse width) for each patient. Unified Parkinson's Disease Rating Scale II Thought Disorder scores, used as a clinical assessment tool to evaluate the presence of psychosis at each visit, were also collected. The data were compiled into a database and analyzed. RESULTS: The lifetime incidence of psychosis in this cohort of patients was 28.1%. The data suggest that risk of psychosis remains fairly constant throughout the first 5 years after implantation of a DBS system and that patients older at the time of receiving the first DBS implant are not only more likely to develop psychosis, but also to develop symptoms sooner than their younger counterparts. Further analysis provides evidence that psychosis is largely independent of the clinically used electrode contact and of stimulation parameters prior to psychosis onset. CONCLUSIONS: Although symptoms of psychosis are widely seen in patients with Parkinson's disease in the years following stimulator placement, results of the present suggest that most psychoses occurring postoperatively are likely independent of implantation and stimulation settings.

Deep brain stimulation of the subthalamic nucleus increases the risk of sialorrhea in patients with advanced Parkinson's disease.

INTRODUCTION: Sialorrhea is a common neurological manifestation of Parkinson's disease (PD). No specifically designed prospective study has tested the effects of deep brain stimulation of the subthalamic nucleus (STN-DBS) on sialorrhea in patients with advanced PD. We focused on the effect of STN-DBS on the incidence of sialorrhea in patients with PD. METHODS: This multicenter, prospective, non-randomized concurrent clinical trial analyzed the incidence of sialorrhea during long-term follow-up in 170 patients with advanced PD (84 patients with STN-DBS and 86 patients with medication therapy). RESULTS: After STN-DBS, 58.1% of patients presented with sialorrhea (Drooling Rating Scale (DRS) > 5) compared with 39.3% of patients with medication therapy (P < 0.001). STN-DBS stimulation demonstrated a significant increase in DRS and Drooling Severity and Frequency Scale (DSFS) compared with the patients with medication therapy (P < 0.001). At follow-up, the onabotulinumtoxin-A (BTX-A) injection ratio was significantly higher in the STN-DBS group (29.8% vs. 11.9%, P = 0.0057) compared with the patients with medication therapy. CONCLUSIONS: STN-DBS increased the risk of sialorrhea in patients with advanced PD. TRIAL REGISTRATION: clinicaltrials. gov (NCT06090929).

Neurocognitive changes at different follow-up times after bilateral subthalamic nucleus deep brain stimulation in patients with Parkinson's disease.

Background: Bilateral deep thalamic nucleus brain stimulation (STN-DBS) surgery is often used to treat the motor symptoms of patients with Parkinson's disease. The change of neurocognitive symptoms in patients is, however, still unclear. Objective: We aimed at analyzing the deterioration of neurocognitive symptoms in patients with Parkinson's disease after deep brain stimulation surgery under different follow-up times. Methods: A comprehensive literature review was conducted using Pubmed, Cochrane Library, and Web of Science to screen eligible study records, the meta-analysis was performed using an inverse variance method and a random-effects model. Additionally, the areas of analysis include five: cognition, executive function, memory capacity, and verbal fluency (phonetic fluency and semantic fluency). They were analyzed for changes at six and twelve months postoperatively compared to baseline. The Meta-analysis has been registered with PROSPERO under the registration number: CRD42022308786. Results: In terms of overall cognitive performance, executive function, and memory capacity, the original studies show a trend of improvement in these areas at 12 months postoperatively compared with 6 months, at variance, patients did not improve or deteriorated in phonetic fluency(d = -0.42 at both 6-month and 12-month follow-up) and semantic fluency from 6 to 12 months postoperatively. Conclusion: In terms of most neurocognitive symptoms, including cognitive ability, executive function, and learning memory capacity, bilateral STN-DBS surgery appears to be safe at relatively long follow-up times. However, postoperative phonetic and semantic fluency changes should still not be underestimated, and clinicians should pay more attention to patients' changes in both.

Analyses of the clinical factors and freezing of gait in association with the quality-of-life indexes in Parkinson's disease subjects with and without STN-DBS therapy.

INTRODUCTION: In this research, paying particular attention to freezing of gait (FOG), we aimed to investigate the associations between the clinical features and quality of lilfe (QOL) indexes comparatively in our PD subjects with and without STN-DBS therapy. METHODS: All consecutive PD subjects with and without STN-DBS who applied to our movement disorders outpatient clinics between January/2022 and September/2022; and accepted to participate in the study were enrolled. The demographic data and clinical features were noted. Besides, the MDS-UPDRS, the FOG Questionnaire (FOGQ) and the Parkinson's Disease Questionnaire (PDQ-39) have also been performed on all individuals. RESULTS: Overall, 105 patients with PD participated in this study (34 patients with STN-DBS, 71 patients without STN-DBS). No difference was found in the PDQ-39 scores between patients with and without STN-DBS. The correlation analyses between the PQQ-39 scores and the clinical parameters revealed significant moderate correlations with the FOGQ score and low correlations with MDS-UPDRS scores. The analyses repeated in either patient group showed that there were no correlations between the MDS-UPDRS scores and PDQ-39 indexes in the DBS group. Besides, the correlations between the PDQ-39 scores and the FOG scores were more prominent in patients without DBS therapy. CONCLUSION: FOG was found to be associated with worse QOL status in both patients with and without STN-DBS therapy. However, the correlations analyses in either group showed that FOG was a more significant determinant in the QOL indexes in patients without DBS. Future studies evaluating the impact of other clinical features such as falls and gait impairment in QOL of patients with STN-DBS may provide contributions to the current evidence.

Intraoperative transcutaneous electroacupoint stimulation on early postoperative fatigue in patients with Parkinson's disease undergoing deep brain stimulation surgery.

Background: In this clinical trial, we evaluated the effects of transcutaneous electroacupoint stimulation (TEAS) on postoperative fatigue (POF) in Parkinson disease (PD) patients undergoing deep brain stimulation (DBS) surgery. Methods: A total 60 PD patients undergoing DBS surgery were enrolled. They were randomized to receive either electrical stimulation [alternative frequency 2/10 Hz, dense and disperse, intensity adjusted to the maximum tolerated by the participants (6-15 mAmp)] via surface electrodes (TEAS group) or surface electrodes only without electrical stimulation (Con group) at bilateral Zusanli and Sanyinjiao acupuncture points. All participants received their assigned intervention (TEAS or Con) during the 1st stage of surgery [(except during microelectrode recording (MER)] and the entire 2nd stage of surgery. Intraoperative anesthetic requirements were adjusted based on bispectral index (BIS) monitor. POF was assessed by Christensen fatigue scales (ChrFS), along with Quality of Recovery-15 (QoR-15) and mini-mental state examination (MMSE) postoperatively over a 7-day-period. We recorded the usage of rescue analgesics and anti-emetics. Results: Fifty-nine patients' datasets were included for final analyses. Fewer patients in TEAS experienced severe POF (defined as ChrFS ≥6) at T3 than those in the Con group (TEAS vs. Con: 7 vs. 22, p < 0.001). During the 1st stage of surgery, more patients in Con group required dexmedetomidine infusion (TEAS vs. Con: 2 vs. 6; P < 0.01). Total dosages of propofol and remifanil during the 2nd stage of surgery were TEAS vs. Con: 374.7 ± 61.2 vs 421.5 ± 81.9; p < 0.001 and 572.3 ± 82.0 vs. 662 ± 148.2; P < 0.001, respectively. Postoperative rescue analgesics (TEAS vs. Con: 2 vs. 6; P < 0.001) were used less in the TEAS group. TEAS patients reported better POF, MMSE and QoR15 scores than those in the Con group during most of the assessment period. Conclusions: Intraoperative TEAS decreased the severity of POF, reduced intraoperative anesthetic requirements and facilitated post-DBS recovery in this group of PD patients.

Structural Brain Connectivity Guided Optimal Contact Selection for Deep Brain Stimulation of the Subthalamic Nucleus.

BACKGROUND: Deep brain stimulation (DBS) of the subthalamic nucleus (STN) is an effective therapy in ameliorating the motor symptoms of Parkinson disease. However, postoperative optimal contact selection is crucial for achieving the best outcome of deep brain stimulation of the subthalamic nucleus surgery, but the process is currently a trial-and-error and time-consuming procedure that relies heavily on surgeons' clinical experience. METHODS: In this study, we propose a structural brain connectivity guided optimal contact selection method for deep brain stimulation of the subthalamic nucleus. Firstly, we reconstruct the DBS electrode location and estimate the stimulation range using volume of tissue activated from each DBS contact. Then, we extract the structural connectivity features by concatenating fractional anisotropy and the number of streamlines features of activated regions and the whole brain regions. Finally, we use a convolutional neural network with convolutional block attention module to identify the structural connectivity features for the optimal contact selection. RESULTS: We review the data of 800 contacts from 100 patients with Parkinson disease for the experiment. The proposed method achieves promising results, with the average accuracy of 97.63%, average precision of 94.50%, average recall of 94.46%, and average specificity of 98.18%, respectively. Our method can provide the suggestion for optimal contact selection. CONCLUSIONS: Our proposed method can improve the efficiency and accuracy of DBS optimal contact selection, reduce the dependence on surgeons' experience, and has the potential to facilitate the development of advanced DBS technology.

The advantages of general anesthesia subthalamic deep brain stimulation for Parkinson's disease in the enhanced recovery after surgery: A randomized clinical trial.

Background and Aims: With advancements in imaging and microelectrode recording techniques, general anesthesia (GA) has emerged as an alternative option for Parkinson's disease (PD) patients undergoing subthalamic nucleus deep brain stimulation (STN-DBS). In this study, we compared the advantages and disadvantages of using GA and local anesthesia for STN-DBS in enhanced recovery after surgery (ERAS). Methods: Surgical outcomes of STN-DBS were evaluated using the unified PD rating scales (UPDRS). CT and magnetic resonance imaging scans are used to evaluate intracranial conditions. State-trait anxiety inventory and hospital anxiety and depression scale are used to evaluate patients' perioperative psychology. Results: Anesthesia method does not significantly impact the accuracy of microelectrode placement or the improvement of postoperative symptoms. However, the local anesthesia group had a higher incidence of intracranial air, as well as higher rates of postoperative complications such as headache, dizziness, vomiting, and delirium. GA effectively alleviated preoperative anxiety and resulted in lower levels of perioperative anxiety and psychological stress compared to local anesthesia. Additionally, the GA group had shorter surgery duration, earlier ambulation, and a shorter average hospital stay. Conclusion: DBS under GA is safe and effective. Due to shorter surgical duration, reduced occurrence of perioperative complications, effective reduction of preoperative anxiety, and faster postoperative recovery, DBS under GA is better aligned with the concept of ERAS.

Temporal Investigations of the Changes in Presynaptic Inhibition Associated With Subthalamic Nucleus-Deep-Brain Stimulation.

BACKGROUND AND PURPOSE: There are controversies regarding the role of presynaptic inhibition (PSI) in the mechanisms underlying the efficacy of deep-brain stimulation (DBS) in Parkinson's disease (PD). We sought to determine the involvement of PSI in DBS-related mechanisms and clinical correlates. METHODS: We enrolled PD subjects who had received subthalamic nucleus DBS (STN-DBS) therapy and had been admitted to our clinic between January 2022 and March 2022. The tibial H-reflex was studied bilaterally during the medication-off state, and all tests were repeated 10 and 20 minutes after the simulation was turned off. Simultaneous evaluations based on the Movement-Disorder-Society-sponsored revision of the Unified Parkinson's Disease Rating Scale part III (MDS-UPDRS-III) were performed in all of the patients. RESULTS: Ultimately we enrolled 18 patients aged 58.7±9.3 years (mean±standard deviation, 10 females). Fifty percent of the patients showed a decrease in the MDS-UPDRS-III score of more than 60% during the stimulation-on period. Comparative analyses of the repeated measurements made according to the stimulation status revealed significant differences only in the left H-reflex/M-response amplitude ratio (H/M ratio). However, no difference in the left H/M ratio was found in the subgroup of patients with a prominent clinical response to stimulation (n=9). Analyses of the less-affected side revealed differences in the H-reflex amplitude and H/M ratio. CONCLUSIONS: We found evidence of PSI recovery on the less-affected side of our PD subjects associated with STN-DBS. We hypothesize that the involvement of this spinal pathway and its contribution to the mechanisms of DBS differ between individuals based on the severity of the disease and which brainstem regions and descending tracts are involved.

Automatic localization of target point for subthalamic nucleus-deep brain stimulation via hierarchical attention-UNet based MRI segmentation.

BACKGROUND: Deep brain stimulation of the subthalamic nucleus (STN-DBS) is an effective treatment for patients with advanced Parkinson's disease, the outcome of this surgery is highly dependent on the accurate placement of the electrode in the optimal target of STN. PURPOSE: In this study, we aim to develop a target localization pipeline for DBS surgery, considering that the heart of this matter is to achieve the STN and red nucleus segmentation, a deep learning-based automatic segmentation approach is proposed to tackle this issue. METHODS: To address the problems of ambiguous boundaries and variable shape of the segmentation targets, the hierarchical attention mechanism with two different attention strategies is integrated into an encoder-decoder network for mining both semantics and fine-grained details for segmentation. The hierarchical attention mechanism is utilized to suppress irrelevant regions in magnetic resonance (MR) images while build long-range dependency among segmentation targets. Specifically, the attention gate (AG) is integrated into low-level features to suppress irrelevant regions in an input image while highlighting the salient features useful for segmentation. Besides, the self-attention involved in the transformer block is integrated into high-level features to model the global context. Ninety-nine brain magnetic resonance imaging (MRI) studies were collected from 99 patients with Parkinson's disease undergoing STN-DBS surgery, among which 80 samples were randomly selected as the training datasets for deep learning training, and ground truths (segmentation masks) were manually generated by radiologists. RESULTS: We applied five-fold cross-validation on these data to train our model, the mean results on 19 test samples are used to conduct the comparison experiments, the Dice similarity coefficient (DSC), Jaccard (JA), sensitivity (SEN), and HD95 of the segmentation for STN are 88.20%, 80.32%, 90.13%, and 1.14 mm, respectively, outperforming the state-of-the-art STN segmentation method with 2.82%, 4.52%, 2.56%, and 0.02 mm respectively. The source code and trained models of this work have been released in the URL below: https://github.com/liuruiqiang/HAUNet/tree/master. CONCLUSIONS: In this study, we demonstrate the effectiveness of the hierarchical attention mechanism for building global dependency on high-level semantic features and enhancing the fine-grained details on low-level features, the experimental results show that our method has considerable superiority for STN and red nucleus segmentation, which can provide accurate target localization for STN-DBS.