Deep Brain Stimulation Procedures Research Articles

A Meta-Analysis of Medication Reduction and Motor Outcomes After Awake Versus Asleep Deep Brain Stimulation for Parkinson Disease.

There remains significant debate regarding the performance of deep brain stimulation (DBS) procedures for Parkinson disease (PD) under local or general anesthesia. The aim of this meta-analysis was to compare the clinical outcomes between "asleep" DBS (general anesthesia) and "awake" DBS (local anesthesia) for PD. We conducted a comprehensive literature review of all published studies on DBS for PD following PRISMA guideline on PubMed and Cochrane library from January 2004 to April 2023. Inclusion criteria included cohort ≥15 patients, clinical outcomes data which included Unified Parkinson's Disease Rating Scale (UPDRS) score and levodopa equivalent daily dosage (LEDD), and ≥3 months of follow-up. Analysis was conducted using Stata software. There were 18 articles that met inclusion criteria. On meta-analysis, there were no significant differences between awake or asleep DBS with regard to percent change in UPDRS III "off" med/"on" DBS condition (P = .6) and LEDD score (P = .99). On subgroup analysis, we found that the choice of target had no significant effect on improvement of UPDRS III (P = 1.0) or LEDD (P = .99) change for the asleep vs awake operative approach. There were also no statistically significant differences between microelectrode recording (MER) use and no MER use in postoperative UPDRS III (P = 1.0) or LEDD improvement (P = .90) between awake and asleep surgery. There was no significant difference in the primary motor outcomes and LEDD improvement between asleep vs awake DBS. The variables of target selection and MER use had no statistically significant impact on outcome. We find that asleep techniques are both safe and effective compared with the awake technique.

Intraoperative DBS targeting of the globus pallidus internus by using motor evoked potentials

ObjectivesTarget localization for deep brain stimulation (DBS) is a crucial step that influences the clinical benefit of the DBS procedure together with the reduction of side effects. In this work, we address the feasibility of DBS target localization in the globus pallidus internus (GPi) aided by intraoperative motor evoked potentials (MEP) with emphasis on the reduction of capsular side effects. Material and methodsMicro-macroelectrode recordings were performed intraoperatively on 20 patients that underwent DBS treatment of the GPi (GPi-DBS). MEP were elicited intraoperatively by microelectrode stimulation during stereotactic DBS surgery. We studied the relationship between MEP thresholds and the internal capsule (IC) proximity. ResultsWe found a significant correlation between intraoperative MEP thresholds and IC proximity. ConclusionsWe provide further evidence of the role of MEPs for DBS target localization in the GPi, which extends and confirms the usefulness of MEPs as previously reported by DBS target localization studies dealing with the subthalamic and thalamic nuclei. Our approach is advantageous in that it provides criteria to determine the DBS target without the need to rely on a patient's response while avoiding capsular effects.

Deep brain stimulation in Latin America in comparison with the US and Europe in a real-world population: indications, demographics, techniques, technology, and adverse events.

The aim of this study was to provide geographic comparisons of deep brain stimulation (DBS) procedures in Latin America with the US and Europe regarding primary indications, demographic information, clinical and device-related adverse events, technology used, and patient outcomes using the Medtronic Product Surveillance Registry data as of July 31, 2021. Two thousand nine hundred twelve patients were enrolled in the registry (2782 received DBS and 1580 are currently active). Fourteen countries contributed 44,100 years of device experience to the registry. DBS centers in Latin America are located in Colombia (n = 3), Argentina (n = 1), Brazil (n = 1), and Mexico (n = 1). Fisher's exact test was used to compare the difference in proportions of categorical variables between regions. The Wilcoxon signed-rank test was used for the EQ-5D index score change from baseline to follow-up. The most common indication for DBS was Parkinson's disease across all regions. In Latin America, dystonia was the second most common indication, compared to essential tremor in other regions. There was a striking finding with respect to age-patients were an average of 10 years younger at DBS implantation in Latin America. This difference was most likely due to the greater number of patients with dystonia receiving the device implants. The intraoperative techniques were quite similar, showing the same level of quality and covering the main principles of the surgeries with some variations in the brand of frames, planning software, and microrecording systems. Rechargeable batteries were significantly more common in Latin America (72.37%) than in the US (6.44%) and Europe (9.9%). Staging of the DBS procedure differed, with only 11.84% in Latin America staging the procedure compared with 97.58% and 34.86% in the US and Europe, respectively. The EQ-5D score showed significant improvements in all regions during the first 6-12 months (p < 0.0001). However, the 24-month follow-up only showed an improvement in the scale for Latin America (p < 0.0001). DBS was performed in Latin America with similar indications, techniques, and technology as in the US and Europe. Important differences were found, with Latin America implementing more regular use of rechargeable devices, including younger patients at the time of surgery, and showing more sustained quality of life improvements at 24 months of follow-up. The authors hypothesize that these disparities stem from differences in resources among regions. However, more studies are needed to standardize DBS practice across the world to improve patients' quality of life and provide high-quality care.

Demographics of focused ultrasound thalamotomy for essential tremor and trends in deep brain stimulation surgery after its introduction in the USA

BackgroundEssential tremor (ET) is a movement disorder that affects 4%–5% of adults >65 years. For patients with medically refractory ET, neurosurgical interventions such as deep brain stimulation (DBS) and unilateral...

Intracerebral hemorrhage after deep brain stimulation surgery guided with microelectrode recording: analysis of 297 procedures

ObjectivesReport the incidence of symptomatic and asymptomatic intracerebral hemorrhage (ICH) in patients submitted to deep brain stimulation (DBS) guided with microelectrode recording (MER) with further analysis of potential risk factors, both inherent to the patient and related to the pathology and surgical technique. MethodsWe performed a retrospective observational study. 297 DBS procedures were concluded in 277 patients in a single hospital centre between January 2010 and December 2020. All surgeries were guided with MER. We analysed the incidence of symptomatic and asymptomatic ICH and its correlation to age, sex, diagnosis, hypertension and perioperative hypertension, diabetes, dyslipidaemia, antiplatelet drugs, anatomic target, and number of MER trajectories. ResultsThere were a total of 585 electrodes implanted in 277 patients. 16 ICH were observed, of which 6 were symptomatic and 10 asymptomatic, none of which incurred in permanent neurological deficit. The location of the hemorrhage varied between cortical and subcortical plans, always in relation with the trajectory or the final position of the electrode. The incidence of symptomatic ICH per lead-implantation was 1%, and the CT-scan demonstrated asymptomatic ICH in 1.7% more patients. Male patients or with hypertension are 2.7 and 2.2 times more likely to develop ICH, respectively. However, none of these characteristics has been shown to have a statistically significant association with the occurrence of ICH, as well as age, diagnosis, diabetes, dyslipidaemia, antiplatelet drugs, anatomic target, number of MER trajectories and perioperative hypertension. ConclusionsMER-guided DBS is a safe technique, with low incidence of ICH and no permanent deficits in our study. Hypertension and male sex seem to be risk factors for the development of ICH in this surgery. Nevertheless, no statistically significant factors were found for the occurrence of this complication.

Implementation of Pharmacist-Led Medication Review Service for Parkinson's Disease Patients Admitted for Deep Brain Stimulation.

Objective The purpose of this study was to determine the clinical impact of a specialized pharmacist-led medication assessment on the incidence of dopamine antagonists administered for patients with Parkinson's disease after deep brain stimulation (DBS). Methods This was a single-center, Institutional Review Board-approved, two-phase study with pre- and post-implementation cohorts of patients who were 18 years of age or older who underwent DBS for treatment of Parkinson's disease. The primary endpoint was the incidence of dopamine antagonists administered after DBS procedure. Secondary endpoints included the incidence of dopamine antagonists ordered; restarting home Parkinson's disease regimen; rate of tardive dyskinesia; length of hospital stay; and incidence of sitters, restraints, and medications administered for acute agitation. Statistical analysis included Fisher's exact test for categorical data, unpaired t-test for continuous data, and descriptive statistics for all other data. Results The incidence of dopamine antagonists administered was 1 (1.2%) versus 1 (25%) for the pre- and post-implementation groups, respectively (P = 0.09). Restarting of home Parkinson's disease regimen was 30 (36.1%) versus 4 (100%); P = 0.021. The average length of stay was 1.9 days versus 1.3 days. Incidence of sitters was 1 (1.2%) versus 0 (0%), and incidence of restraints was 0 (0%) versus 0 (0%). Incidence of acute agitation medications administered was 9 (10.8%) versus 0 (0%). The secondary endpoints were not significant except for the restarting of home medication regimen. Conclusion The specialized pharmacist-led medication review service identified a single incident of inappropriate medications administered for Parkinson's disease patients status post DBS. However, it did significantly increase the incidence of the restart of Parkinson's disease home regimen.

Minimizing hemorrhagic and perioperative complications in deep brain stimulation surgery in a series of 191 patients operated on over 4 years.

Intracranial hemorrhage (ICH) in functional neurosurgery is a relatively rare but serious complication. One of the possible risk factors related to ICH is the number of trajectories made for microelectrode recording (MER). Authors who solely rely on macrostimulation using macroelectrodes argue that the incidence of ICH is much lower while maintaining good clinical efficacy of deep brain stimulation (DBS). The present study aimed to assess the incidence of ICH in DBS procedures by reducing to the minimum the number of brain passes and the diameter of guiding cannulas. For this reason, we used one MER guiding cannula exclusively for track making with subsequent macrostimulation done through the implanted DBS electrode. All DBS procedures performed between January 2018 and January 2022 in the Department of Neurosurgery of the Institute of Psychiatry and Neurology in Warsaw were analyzed for possible ICH and other perioperative complications. The DBS lead was implanted by an MR image-guided and intraprocedural CT-verified approach. No MER was done. During four years 191 patients underwent 267 DBS lead implantations in 252 stereotactic procedures. ICH occurred in 2 patients. Both were symptomatic. Adverse symptoms resolved within a week. Two DBS leads required replacement. There was 1 case of hematoma at the implantable pulse generator (IPG) site and 1 case of pneumothorax due to tunneling of the extension. Our surgical technique has a low incidence of ICH. Symptomatic ICH affected 2 patients. The other perioperative complications mentioned above required repeated surgery or conservative treatment. No patient suffered from permanent deficits.

Application accuracy of Neuromate robot‐guided deep brain stimulation procedures using the non‐invasive frameless Neurolocate registration system

AbstractObjectiveto measure the in vivo application accuracy of Neuromate robot‐assisted deep brain stimulation procedures (DBS) using the new, non‐invasive, frameless Neurolocate registration method.MethodsNeurolocate accuracy was measured in 17 patients undergoing DBS (32 leads). The registration was obtained by automatic recognition of the spatial location of the Neurolocate fiducials, fixed on the robot arm, on 3D intraoperative computerized tomography (CT) images relative to the patient's skull contours. Application accuracy was measured as the Euclidian distance between the points theoretically targeted on preoperative magnetic resonance imagingand the tip of the guiding tube visible on intraoperative CT images after merging images.ResultsMean robot inaccuracy was 0.72 mm (SD 0.40; range 0.2–1.7 mm). Inaccuracies ≥1.5 mm were observed in 2/32 cases.ConclusionOur study confirms in vivo that the accuracy of the Neurolocate registration is compatible with the accuracy required for DBS procedures.

The Five-Factor Modified Frailty Index as a Predictor of Outcomes in Deep Brain Stimulation Surgery for Parkinson's Disease.

Introduction Parkinson's disease (PD) is one of the most common neurodegenerative diseases worldwide. Though there are many pharmacological therapeutics approved today for PD, surgical interventions such as deep brain stimulation (DBS) have shown convincing symptom mitigation and minimal complication rates in aggregate. Recently, the concept of frailty - defined as reduced physiologic reserve and function affecting multiple systems throughout the patient - has gained traction as a predictor of short-term postoperative morbidity and mortality. As such, the Modified Frailty Index-5 (mFI-5) is a postoperative morbidity predictor based on five factors and has been used in neurosurgical subspecialties such as tumor, vascular, and spine. Yet, there is minimal literature assessing frailty in the field of functional neurosurgery. With the prevalence of DBS in PD, this study evaluated the mFI-5 as a predictor of postoperative complications in a selected patient population. Methods The American College of Surgeons National Surgical Quality Improvement Program 2010-2019 Database was queried for Current Procedural Terminology (CPT) codes, as well as the International Classification of Diseases (ICD)-9 and ICD-10 codes pertaining to DBS procedures in PD patients. Each patient was scored by the mFI-5 protocol and stratified into groups of No Frailty (mFI-5=0), Moderate Frailty (mFI-5=1), and Significant Frailty (mFI-5≥2). The No Frailty group was used as a reference in multivariate and univariate analyses of the groups. Results A total of 1,645 subjects were included in the study and were subcategorized into groups of No Frailty (N=877), Moderate Frailty (N=561), and Significant Frailty (N=207) based on their frailty scores. The subjects' mean age was 65.8±9.4 years. Overall, 1,161 (70.6%) were male, while 484 (29.4%) were female. With reference to the No Frailty group in multivariate analysis, patients with moderate frailty experienced greater unplanned readmission (OR 2.613, 95% CI 1.143-5.973, p=0.023), while those with significant frailty experienced greater unplanned readmission (OR 3.723, 95% CI 1.376-10.073, p=0.010), any readmission (OR 2.396, 95% CI 1.098-5.230, p=0.028), non-home discharge (OR 4.317, 95% CI 1.765-10.562, p<0.001), and complications in aggregate (OR 2.211, 95% CI 1.285-3.806, p=0.004). Conclusions Until now, the available clinical tools were limited in providing accurate predictions with minimal information for postoperative outcomes in DBS for PD patients. Our data give clinicians insight into the relationship between frailty and surgical outcomes and will assist physicians in preparing for postoperative care by predicting outcomes of significantly frail PD patients receiving DBS therapy.

Intracerebral hemorrhage after deep brain stimulation surgery guided with microelectrode recording: analysis of 297 procedures

ObjectivesReport the incidence of symptomatic and asymptomatic intracerebral hemorrhage (ICH) in patients submitted to deep brain stimulation (DBS) guided with microelectrode recording (MER) with further analysis of potential risk factors, both inherent to the patient and related to the pathology and surgical technique. MethodsWe performed a retrospective observational study. 297 DBS procedures were concluded in 277 patients in a single hospital centre between January 2010 and December 2020. All surgeries were guided with MER. We analysed the incidence of symptomatic and asymptomatic ICH and its correlation to age, sex, diagnosis, hypertension and perioperative hypertension, diabetes, dyslipidaemia, antiplatelet drugs, anatomic target, and number of MER trajectories. ResultsThere were a total of 585 electrodes implanted in 277 patients. 16 ICH were observed, of which 6 were symptomatic and 10 asymptomatic, none of which incurred in permanent neurological deficit. The location of the hemorrhage varied between cortical and subcortical plans, always in relation with the trajectory or the final position of the electrode. The incidence of symptomatic ICH per lead-implantation was 1%, and the CT-scan demonstrated asymptomatic ICH in 1.7% more patients. Male patients or with hypertension are 2.7 and 2.2 times more likely to develop ICH, respectively. However, none of these characteristics has been shown to have a statistically significant association with the occurrence of ICH, as well as age, diagnosis, diabetes, dyslipidaemia, antiplatelet drugs, anatomic target, number of MER trajectories and perioperative hypertension. ConclusionsMER-guided DBS is a safe technique, with low incidence of ICH and no permanent deficits in our study. Hypertension and male sex seem to be risk factors for the development of ICH in this surgery. Nevertheless, no statistically significant factors were found for the occurrence of this complication.

A - 106 Predicting Depression in Individuals with Parkinson's Disease Using the Repeatable Battery for the Assessment of Neuropsychological Status.

This study investigates whether deficits in specific cognitive domains predict depression in individuals with Parkinson's disease. Neurocognitive domains are measured by the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS). Affective symptoms are measured by the Personality Assessment Inventory (PAI). A simultaneous hierarchical multiple regression with three univariately predicting RBANS indices was used to predict the PAI Depression Scale. Participants were individuals diagnosed with Parkinson's disease who underwent neuropsychological evaluation as candidates for deep brain stimulation procedures. The sample included 31 participants, between ages 41 to 75, with a mean age of 61.29. Twenty-seven were male and four were female. Twenty-six were white, one was African-American, one was Hispanic, one was Asian, two were not racially identified. The model was significant with a large effect size, R2 = 0.444, F(3,27) = 7.177, p < 0.001, indicating Attention, Visuospatial/constructional, and Immediate Memory RBANS indices accounted for 44% of the variation found in depression as measured by the PAI. Attention had 15% of unique variance accounting for one third of the 44% predicted by the regression model. Visuospatial/constructional had 9% unique variance, indicating that approximately 20% of the model variance is in common between the predictors and depression. The analysis found a significant negative correlation between depression and cognitive deficits, supporting the hypothesis that cognitive deficits in one or more of the RBANS domains predicts depression in individuals with Parkinson's disease.

Postoperative infection problems in DBS applications

Deep brain stimulation (DBS) is a significant neuromodulation method for treating neurological and psychiatric disorders. Despite its efficacy, complications, particularly infections, are a concern. This article reviews the prevalence, risk factors, pathogens, infection locations, timing, surgical approaches, prevention strategies, and treatment methods associated with infections following DBS procedures. DBS surgeries have gained popularity due to their adjustability, but infections pose challenges. Surgical site infections (SSIs) are common (0% to 24% cases) and extensively studied regarding patient groups, locations, timing, and pathogens. Expanding patient groups, including conditions like Tourette syndrome and epilepsy, have varying infection risks. Infections occur at burr-hole, extension, and implantable pulse generator (IPG) sites. Staphylococcus aureus is a primary pathogen, yet bacterial DNA on IPGs and colonization complicate understanding. Surgical approaches, staged or non-staged, show comparable infection rates. The influence of repetitive pulse generator replacements on infection rates is debated. Lead externalization, topical vancomycin powder, and other factors impact infection risk. Treating DBS-related infections often requires hardware extraction and antibiotic treatment. Innovations like ethylene oxide sterilization and hydrogen peroxide show potential. Algorithms suggest partial explantation for localized infections. Cost analyses favor starting with antibiotics. Infections persist despite progress; understanding risks, pathogens, and strategies is vital for optimal outcomes in DBS.

Complications of deep brain stimulation in Parkinson's disease: a single-center experience of 517 consecutive cases.

The number of deep brain stimulation (DBS) procedures is rapidly rising as well as the novel indications. Reporting adverse events related to surgery and to the hardware used is essential to define the risk-to-benefit ratio and develop novel strategies to improve it. To analyze DBS complications (both procedure-related and hardware-related) and further assess potential predictive factors. Five hundred seventeen cases of DBS for Parkinson's disease were performed between 2006 and 2021 in a single center (mean follow-up: 4.68 ± 2.86 years). Spearman's Rho coefficient was calculated to search for a correlation between the occurrence of intracerebral hemorrhage (ICH) and the number of recording tracks. Multiple logistic regression analyzed the probability of developing seizures and ICH given potential risk factors. Kaplan-Meier curves were performed to analyze the cumulative proportions of hardware-related complications. Mortality rate was 0.2%, while permanent morbidity 0.6%. 2.5% of cases suffered from ICH which were not influenced by the number of tracks used for recordings. 3.3% reported seizures that were significantly affected by perielectrode brain edema and age. The rate of perielectrode brain edema was significantly higher for Medtronic's leads compared to Boston Scientific's (Χ2(1)= 5.927, P= 0.015). 12.2% of implants reported Hardware-related complications, the most common of which were wound revisions (7.2%). Internal pulse generator models with smaller profiles displayed more favorable hardware-related complication survival curves compared to larger designs (X2(1)= 8.139, P= 0.004). Overall DBS has to be considered a safe procedure, but future research is needed to decrease the rate of hardware-related complications which may be related to both the surgical technique and to the specific hardware's design. The increased incidence of perielectrode brain edema associated with certain lead models may likewise deserve future investigation.

Trends and disparities in deep brain stimulation utilization in the United States: a Nationwide Inpatient Sample analysis from 1993 to 2017

Deep brain stimulation (DBS) is an approved treatment option for Parkinson's Disease (PD), essential tremor (ET), dystonia, obsessive-compulsive disorder and epilepsy in the United States. There are disparities in access to DBS, and clear understanding of the contextual factors driving them is important. Previous studies aimed at understanding these factors have been limited by single indications or small cohort sizes. The aim of this study is to provide an updated and comprehensive analysis of DBS utilization for multiple indications to better understand the factors driving disparities in access. The United States based National Inpatient Sample (NIS) database was utilized to analyze the surgical volume and trends of procedures based on indication, using relevant ICD codes. Predictors of DBS use were analyzed using a logistic regression model. DBS-implanted patients in each indication were compared based on the patient-, hospital-, and outcome-related variables. Our analysis of 104,356 DBS discharges from 1993 to 2017 revealed that the most frequent indications for DBS were PD (67%), ET (24%), and dystonia (4%). Although the number of DBS procedures has consistently increased over the years, radiofrequency ablation utilization has significantly decreased to only a few patients per year since 2003. Negative predictors for DBS utilization in PD and ET cohorts included age increase and female sex, while African American status was a negative predictor across all cohorts. Significant differences in patient-, hospital-, and outcome-related variables between DBS indications were also determined. Demographic and socioeconomic-based disparities in DBS use are evident. Although racial disparities are present across all indications, other disparities such as age, sex, wealth, and insurance status are only relevant in certain indications. This work was supported by Alan & Susan Hudson Cornerstone Chair in Neurosurgery at University Health Network.

A new strategy for treating drug-resistant focal aware seizures: thalamic specific nuclei deep brain stimulation. Illustrative case.

Focal aware seizures (FASs) are relatively common and frequently pharmaco-resistant. If the seizure onset zone (SOZ) is in eloquent cortical areas, making resective surgery risky and inadvisable, deep brain stimulation (DBS) of the anterior nucleus of the thalamus, which is efficacious in less than half of the cases, has been the main alternative. New targets should be searched to address this deficiency. The present study aims to determine if DBS of different thalamic specific nuclei can modulate the abnormal electrical activity of the SOZ located in their respective cortical projection areas. Herein, the authors present the first patient in an ongoing trial. A 60-year-old female patient presented with 25-year history of pharmaco-resistant focal aware visual seizures frequently evolving to focal impaired awareness seizures. The SOZ was in the right occipital lobe (positron emission tomography-computed tomography/video electroencephalography). Magnetic resonance imaging was normal. She underwent ipsilateral lateral geniculate nucleus (LGN) DBS procedure. After a 24-month follow-up, seizure frequency decreased by 97%, improving quality of life and daily functioning without complications. This is the first time the LGN has been targeted in humans. The results support the hypothesis that led to this study. This strategy represents a paradigm shift in the way of treating pharmaco-resistant FASs not amenable to resective surgery.

Deep brain stimulation in multiple sclerosis-associated tremor. A large, retrospective, longitudinal open label study, with long-term follow-up

BackgroundTremor affects up to 25%-58% in multiple sclerosis (MS) population. Deep-brain stimulation (DBS) of the ventral-intermediate nucleus (VIM) of the thalamus is considered as a potential option following medical treatments. Long term DBS efficacy is not well known in these patients with a poor outcome mostly related to disease progression. ObjectiveTo report a large and retrospective study of thalamic DBS in MS tremor. MethodsWe conducted a large and retrospective study of patients with MS disabling and pharmacologically resistant upper limb tremor, who underwent thalamic DBS procedure from January 1992 to January 2015 in University Hospital of Henri Mondor, France. Demographic data, clinical assessment and activity daily living were collected. A three-month and twelve-month post-operative assessment with clinical and functional rating scales have been achieved, as well as long term follow-up for most patients. ResultsOne hundred and four patients underwent DBS procedure. There were 71 female (68%) and 33 male (32%). At three-month post-operative assessment, 64% patients were improved clinically and functionally. Among these, 93% of patients kept a good efficacy at one-year post-operative assessment. Mean duration of follow-up for these patients was 6 years. ConclusionWe described a long-term sustained clinical and functional improvement in this large and retrospective report of thalamic DBS. This neuromodulation approach could be a therapeutic option for all severe upper extremity refractory tremor in MS patients.

Model-based image updating in deep brain stimulation with assimilation of deep brain sparse data.

Accuracy of electrode placement for deep brain stimulation (DBS) is critical to achieving desired surgical outcomes and impacts the efficacy of treating neurodegenerative diseases. Intraoperative brain shift degrades the accuracy of surgical navigation based on preoperative images. We extended a model-based image updating scheme to address intraoperative brain shift in DBS surgery and improved its accuracy in deepbrain. We evaluated 10 patients, retrospectively, who underwent bilateral DBS surgery and classified them into groups of large and small deformation based on a 2 mm subsurface movement threshold and brain shift index of 5%. In each case, sparse brain deformation data were used to estimate whole brain displacements and deform preoperative CT (preCT) to generate updated CT (uCT). Accuracy of uCT was assessed using target registration errors (TREs) at the Anterior Commissure (AC), Posterior Commissure (PC), and four calcification points in the sub-ventricular area by comparing their locations in uCT with their ground truth counterparts in postoperative CT (postCT). In the large deformation group, TREs were reduced from 2.5 mm in preCT to 1.2 mm in uCT (53% compensation); in the small deformation group, errors were reduced from 1.25 to 0.74 mm (41%). Average reduction of TREs at AC, PC and pineal gland were significant, statistically (p ⩽ 0.01). With more rigorous validation of model results, this study confirms the feasibility of improving the accuracy of model-based image updating in compensating for intraoperative brain shift during DBS procedures by assimilating deep brain sparsedata.

Dexmedetomidine after deep brain stimulation for prevention of delirium in elderly patients with Parkinson’s disease: protocol for a single-centre, randomised, double-blind, placebo-controlled trial in China

IntroductionParkinson’s disease is one of the most common neurodegenerative diseases. Deep brain stimulation (DBS) can improve motor symptoms in patients with middle and late Parkinson’s disease, reduce the use of...

Factors influencing the reliability of intraoperative testing in deep brain stimulation for Parkinson’s disease

BackgroundSeveral meta-analyses comparing the outcome of awake versus asleep deep brain stimulation procedures could not reveal significant differences concerning the postoperative improvement of motor symptoms. Only rarely information on the procedural details is provided for awake operations and how often somnolence and disorientation occurred, which might hamper the reliability of intraoperative clinical testing. The aim of our study was to investigate possible influencing factors on the occurrence of somnolence and disorientation in awake DBS procedures.MethodsWe retrospectively analyzed 122 patients with Parkinson's disease having received implantation of a DBS system at our centre. Correlation analyses were performed for the duration of disease prior to surgery, number of microelectrode trajectories, AC-PC-coordinates of the planned target, UPDRS-scores, intraoperative application of sedative drugs, duration of the surgical procedure, perioperative application of apomorphine, and the preoperative L-DOPA equivalence dosage with the occurrence of intraoperative somnolence and disorientation.ResultsPatients with intraoperative somnolence were significantly older (p=0.039). Increased duration of the DBS procedure (p=0.020), delayed start of the surgery (p=0.049), higher number of MER trajectories (p=0.041), and the patients’ % UPDRS improvement (p=0.046) also correlated with the incidence of intraoperative somnolence. We identified the main contributing factor to intraoperative somnolence as the use of sedative drugs applied during skin incision and burr hole trepanation (p=0.019). Perioperatively applied apomorphine could reduce the occurrence of somnolent phases during the operation (p=0.026).ConclusionSeveral influencing factors were found to seemingly increase the risk of intraoperative somnolence and disorientation, while the use of sedative drugs seems to be the main contributing factor. We argue that awake DBS procedures should omit the use of sedatives for best clinical outcome. When reporting on awake DBS surgery these factors should be considered and adjusted for, to permit reliable interpretation and comparison of DBS study results.

ID: 219306 Characterization, Risk, and Predictors of Pocket Infection in Deep Brain Stimulation

Although relatively rare, infection can be a serious and disabling complication for Deep Brain Stimulation (DBS) procedures, subjecting patients to additional surgical interventions. Previous meta-analyses report neurostimulator pocket infection risk rates between 3.0-7.3% for DBS procedures. However, most prior reports are based on single-center studies, utilize differing statistical methods to calculate rates, vary in length of patient follow-up, and contain limited information on the predictors and long-term clinical impact of infections.