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.

Pocket-Size Wireless Nanoelectrospray Ionization Mass Spectrometry for Metabolic Analysis of Salty Biofluids and Single Cells.

Analysis of volume-limited biological samples such as single cells and biofluids not only benefits clinical purposes but also promotes fundamental research in life sciences. Detection of these samples, however, imposes strict requirements on measurement performance because of the minimal volume and concentrated salts of the samples. Herein, we developed a self-cleaning nanoelectrospray ionization device powered by a pocket-size "MasSpec Pointer" (MSP-nanoESI) for metabolic analysis of salty biological samples with limited volume. The self-cleaning effect induced by Maxwell-Wagner electric stress helps with keeping the borosilicate glass capillary tip free from clogging and thus increasing salt tolerance. This device possesses a high sample economy (about 0.1 µL per test) due to its pulsed high voltage supply, sampling method (dipping the nanoESI tip into analyte solution), and contact-free electrospray ionization (ESI) (the electrode does not touch the analyte solution during ESI). High repeatable results could be acquired by the device with a relative standard deviation (RSD) of 1.02% for voltage output and 12.94% for MS signals of caffeine standard. Single MCF-7 cells were metabolically analyzed directly from phosphate buffered saline, and two types of untreated cerebrospinal fluid from hydrocephalus patients were distinguished with 84% accuracy. MSP-nanoESI gets rid of the bulky apparatus and could be held in hand or put into one's pocket for transportation, and it could operate for more than 4 h without recharge. We believe this device will boost scientific research and clinical usage of volume-limited biological samples with high-concentration salts in a low-cost, convenient, and rapid manner.

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.

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.

The Effects of Deep Brain Stimulation on Motor Unit Activities in Parkinson's Disease based on High-Density Surface EMG Analysis.

Tremor in Parkinson's disease (PD) is caused by synchronized activation bursts in limb muscles. Deep Brain Stimulation (DBS) is an effective clinical therapy for inhibiting tremor and improving movement disorders in PD patients. However, the neural mechanism of how tremor symptom is suppressed by DBS at motor unit (MU) level remains unclear. This paper developed a data acquisition platform for collecting physiological data in PD patients. Both high-density surface Electromyography (HD-sEMG) and kinematics data were collected concurrently before and after DBS surgery. The MU behaviors were obtained via HD-sEMG decomposition algorithm to reveal the effect of DBS on PD tremor. A data set of one tremor dominant PD patient acquired in pre-operation and post-operation (DBS-on) phases was analyzed. Preliminary results showed significant changes in MU firing rate and MU synchronization. The analysis approach introduced in this paper provides a novel perspective for studying the neural mechanism of DBS as revealed by MU activities. Clinical Relevance- This study presented an approach to investigate the effect of DBS therapy on improving tremor disorder of PD 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.

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.

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.

[Finite element analysis of the effect of plate placement angle on cervical spine stability in anterior cervical fusion surgery].

OBJECTIVE: Using the method of finite element analysis, to compare the biomechanical properties between the plate deviating from the long axis of the cervical spine and the standard placement of the plate in the anterior cervical fusion surgery. METHODS: A healthy female volunteer was selected and CT scan (C1-T1) was performed. Using Mimics 19.0, Geomagic Studio 2015, Solidworks 2018, Ansys Workbench 17.2 to establish a lower cervical spine (C3-C7) model and to verify the reliability of the model. Subsequently, anterior cervical plates of different angles and lengths were placed to establish an anterior cervical discectomy fusion (ACDF) model. Applying 73.6 N axial pressure and 1 NM pure moment on C3 to make the model produce flexion, extension, lateral bending and rotation activities, observed the model stress cloud diagram and recorded the maximum stress value of the instrument and the intervertebral mobility. RESULTS: The lower cervical spine (C3-C7) finite element model was established and verified against the published literature on the range of motion (ROM) of cervical spine. Effect of steel plate offset axis on stress distribution, maximum stress value and intervertebral ROM of internal fixation apparatus was minimal, and the mechanical effect of steel plate offset was less in double section steel plate than in single section steel plate. CONCLUSION: Little effect on the mechanical stability of the cervical spine was anticipated when the anterior cervical plate was not perfectly aligned with the long axis of the cervical spine. If the tilt of the plate in clinical surgery is less than 20°, there is no need to readjust the position of the plate.

Colorimetric detection of immunomagnetically captured rare number CTCs using mDNA-wrapped single-walled carbon nanotubes.

The number of CTCs in peripheral blood is of great significance for the early diagnosis, recurrence and prognosis evaluation of tumor patients. Consequently, it is required to develop simple and effective technique to realize the capture and detection of rare number CTCs. Herein, a SiO2, gelatin and biotinylated EpCAM aptamer P1 modified Fe3O4 immunomagnetic nanoparticles (IMNs) were prepared for the specific capture and nondestructive release of trace amounts of CTCs. Then, utilizing the peroxidase-like activity of single-walled carbon nanotubes (SWCNTs) and the effect of non-specific DNA sequences on this activity, a colorimetric probe was constructed by modifying the three DNA sequences (mDNA) onto the IMNs. When target cell was present, due to the specific interaction between cells and P1, the conformational structure of P1 was changed. Consequently, the mDNA linked with P1 on IMNs was replaced by the cell and released from IMNs. In this way, the quantification of captured CTCs could be converted to that of released mDNA. This strategy combined the capture and detection of CTCs as a whole and could detect down to 10 cells with a high selectivity. Finally, we achieved the accurate quantification of CTCs in lysed bloods from 12 clinical tumor patients, which exhibited a great promise for further clinical applications.

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.

Development and Initial Validation of the Chinese Version of the Florida Surgical Questionnaire for Parkinson's Disease.

BACKGROUND: Deep brain stimulation (DBS) for Parkinson's disease (PD) has evolved as a well-established treatment in neurosurgery, and identifying appropriate surgical candidates could contribute to better DBS outcomes. The Florida Surgical Questionnaire for Parkinson Disease (FLASQ-PD) is a reasonable screening tool for assessing DBS candidacy in PD patients; however, a Chinese version of FLASQ-PD is needed for functional neurosurgery units in China. In this study, we translated the FLASQ-PD to Chinese and assessed its reliability and validity for Chinese PD patients. METHODS: The FLASQ-PD was translated before the study formally started. A single-center retrospective analysis of FLASQ-PD was performed at the Ruijin Hospital, affiliated with Shanghai Jiaotong University School of Medicine, between July and December 2019. The Unified Parkinson Disease Rating Scale III (UPDRS-III) was also used to assess PD patients on and off medication. All patients were evaluated for surgical candidacy by specialists. RESULTS: Overall, 115 PD patients, 25 with parkinsonism and six with multiple system atrophy were consecutively included. Internal consistency of the Chinese FLASQ-PD was roughly adequate (Cronbach's alpha = 0.664). There were significant differences in mean total scores of the Chinese FLASQ-PD between the diagnostic (Kruskal-Wallis H value = 37.450, p ≤ 0.001) and surgery-candidacy groups (H = 48.352, p ≤ 0.001). Drug improvements in UPDRS-III scores were mildly correlated with the Chinese FLASQ-PD scores in the surgery-ready group (Pearson correlation = 0.399, p=0.001). CONCLUSIONS: The Chinese FLASQ-PD, which is a simple and efficient screening tool for clinicians, was developed and initially validated in this retrospective single-center study.

[Research progress on minimally invasive treatment of anterior pelvic ring fracture].

OBJECTIVE: To summarize the related research results of minimally invasive treatment of anterior pelvic ring fracture, and to improve the understanding of minimally invasive treatment of anterior pelvic ring fracture. METHODS: The literature of minimally invasive treatment of anterior pelvic ring fracture at domestic and overseas in recent years was reviewed, and the reduction and fixation methods of minimally invasive treatment were summarized and analyzed. RESULTS: The pelvic reduction frame may be an effective auxiliary method for minimally invasive reduction of pelvis. The fixation methods of anterior pelvic ring include percutaneous screw fixation, stent fixation, and percutaneous plate fixation. CONCLUSION: One kind of fixation is not applicable to all types of anterior pelvic ring fracture, and the fixation method should be selected according to the type of fracture and the patient's condition to minimize the complications.

Bilateral Posterior Subthalamic Area Deep Brain Stimulation for Essential Tremor: A Case Series.

BACKGROUND: Deep brain stimulation (DBS) of the posterior subthalamic area (PSA) provides a potentially effective treatment for medication-refractory essential tremor (ET). OBJECTIVE: To study the clinical benefits and adverse-event profile of bilateral PSA-DBS for refractory ET. METHODS: Seven patients with refractory ET underwent bilateral PSA-DBS surgery under general anesthesia between September 2017 and May 2018. Clinical outcome assessments, using the Essential Tremor Rating Scale, were performed at 1-, 6-, and 12-month follow-up, except for the last assessment of one patient who was followed up to 9 months. Analysis was focused on changes in patients' motor symptoms and quality of life following surgery as well as documenting the adverse-event profile associated with the surgical PSA-DBS treatment. RESULTS: After surgery, patients' motor symptoms, including upper limb tremor and head tremor, were improved by 84.2% and their quality of life by 81.25% at 1-month follow-up. The clinical benefits to patients were maintained at 6-month and last follow-up. Adverse side effects included dysarthria (n = 4), balance disorder (n = 2), and paresthesia of the right limb (n = 1). No habituation effects were observed throughout the follow-up. CONCLUSION: Bilateral PSA-DBS seems to offer an effective and safe alternative treatment for medically intractable ET, warranting further research into its clinical utility, adverse-event profile, and comparative effectiveness.

Spinal Cord Stimulation with Surgical Lead Improves Pain and Gait in Parkinson's Disease after a Dislocation of Percutaneous Lead: A Case Report.

Spinal cord stimulation (SCS) is receiving increasing interests for treating pain and gait disorders in patients with Parkinson's disease (PD). In an SCS study, it is hard to apply a double-blind approach, especially at low frequencies, as the stimulation normally induces paresthesia which can be perceived by the patient. We herein demonstrate a case treated with SCS in which a blinding design was accomplished by an accidental dislocation of a stimulation lead. A 73-year-old man with PD was admitted to our hospital because of relapsed low back pain. This was due to the dislocation of a previously implanted SCS lead, which caused a decrease in its effectiveness in alleviating pain (from 81 to 43% measured by King's Parkinson's Disease Pain Scale) and improving gait (from 35 to 28% measured by the timed up and go test). A second SCS surgery using a paddle lead solved this problem, with improvements in pain and gait rebounded to 81 and 45%. In this case, the paresthesia induced by SCS (using either a paddle lead or percutaneous leads) was below the threshold of perception when the patient was sitting and standing, and a dislocation of one previously implanted percutaneous lead did not cause evident changes in his sensation of paresthesia. At last follow-up, the patient's quality of life had improved by 40% as measured by the 8-item Parkinson's Disease questionnaire (PDQ-8). This study could serve partly as a proof that low-frequency SCS is effective in improving pain as well as gait problems in PD patients, which was unlikely a result of a placebo effect.

Lead fixation in deep brain stimulation: comparison of three lead anchoring devices in China.

BACKGROUND: The accuracy of deep brain stimulation (DBS) depends on precise electrode positioning, which has been pursued for ideal treatment outcomes. As a critical component of DBS, the fixation performance of lead anchoring devices has been widely studied. Possible reasons for lead shift were analyzed in the current study and we further provided effective solutions to reduce potential manual errors. METHODS: Seventy-nine patients who received DBS implantations at the Ruijin Hospital from April to November 2017 were retrospectively reviewed. Intraoperative lead shifts were measured by C-arm fluoroscopy. Lead adjustment counts were recorded and compared among three lead fixation devices: Stimloc™ (Medtronic, Minneapolis, MN, USA), TouchLoc (SceneRay, Suzhou, China), and the traditional lead anchoring device. RESULTS: Mean (± SD) distances of lead shifts were 0.29 ± 2.42 mm in Stimloc devices, 0.43 ± 0.55 mm in TouchLoc devices, and 1.52 ± 1.05 mm in traditional devices (p < 0.0001). Average numbers of adjustments in this series were 0.3 ± 0.5 in Stimloc devices, 0.3 ± 1.3 in TouchLoc devices, and 1.1 ± 1.0 in traditional devices (p = 0.0001). Pairwise comparisons among the three devices (TouchLoc vs. Stimloc: p = 0.273; TouchLoc vs. Traditional: p = 0.0001; Stimloc vs. traditional: p < 0.0001) suggested significant differences, which were mainly attributed to the traditional devices. CONCLUSIONS: Three lead anchoring devices have been compared for their performance in the accuracy of lead fixation, in which the newly designed lead fixation devices have presented its advantages to the traditional one. In addition to the application of the Stimloc and TouchLoc devices, verification by C-arm fluoroscopy should be performed to provide an intuitive view of the depth deviation of electrode position during DBS electrode implantation.

Bilateral anterior capsulotomy enhances medication compliance in patients with epilepsy and psychiatric comorbidities.

OBJECTIVES: Patients with epilepsy and refractory comorbid psychiatric disorders often experience functional impairments and a lower quality of life as well as showing a lack of compliance with anti-epileptic medication regimens. We reasoned that widespread clinical benefits could be gained if the psychiatric comorbidities among these patients were reduced. In this study, we assessed the utility of anterior capsulotomy in managing medication-refractory comorbid psychotic symptoms and aggression in patients with epilepsy. METHODS: In this retrospective case series, we evaluated the clinical outcomes of 13 epilepsy patients with severe psychiatric comorbidities who had received bilateral anterior capsulotomy. Clinical outcome assessments were performed at 1 week, 6 months, 1 year, and several years after surgery focusing on: (a) severity of psychotic symptoms, as assessed by the 18-item Brief Psychiatric Rating Scale and the Positive and Negative Syndrome Scale; (b) severity of impulsivity and aggression, measured by the Barratt Impulsiveness Scale-11 and the Buss-Perry Aggression Scale; and (c) social function and quality of life, assessed by the Social Disability Screening Scale and the Quality of Life in Epilepsy. RESULTS: After anterior capsulotomy, patients displayed significant improvements of psychotic symptoms, as well as of impulsivity and aggression, along with improvements of social function and quality of life. The clinical benefits to patients were evident within 6 months after surgery and remained stable or continued to improve at a much slower rate thereafter. Furthermore, after anterior capsulotomy all patients complied with epilepsy interventions that they did not comply with prior to surgery. No significant side effects or complications occurred during the study. CONCLUSION: Anterior capsulotomy seems to be a safe and effective treatment for epilepsy patients with otherwise intractable comorbid psychotic symptoms and aggression. Moreover, this neurosurgical treatment may improve the patients' social function, quality of life, and compliance with anti-epilepsy medication regimens.

Deep brain stimulation of the globus pallidus internus versus the subthalamic nucleus in isolated dystonia.

OBJECTIVE: Surgical procedures involving deep brain stimulation (DBS) of the globus pallidus internus (GPi) or subthalamic nucleus (STN) are well-established treatments for isolated dystonia. However, selection of the best stimulation target remains a matter of debate. The authors' objective was to compare the effectiveness of DBS of the GPi and the STN in patients with isolated dystonia. METHODS: In this matched retrospective cohort study, the authors searched an institutional database for data on all patients with isolated dystonia who had undergone bilateral implantation of DBS electrodes in either the GPi or STN in the period from January 30, 2014, to June 30, 2017. Standardized assessments of dystonia and health-related quality of life using the Burke-Fahn-Marsden Dystonia Rating Scale (BFMDRS) and SF-36 were conducted before and at 1, 6, and 12 months after surgery. No patients were lost to the 6-month follow-up; 5 patients were lost to the 12-month follow-up. RESULTS: Both GPi (14 patients) and STN (16 patients) stimulation produced significant improvement in dystonia and quality of life in all 30 patients found in the database search. At the 1-month follow-up, however, the percentage improvement in the BFMDRS total movement score was significantly (p = 0.01) larger after STN DBS (64%) than after GPi DBS (48%). At the 12-month follow-up, the percentage improvement in the axis subscore was significantly (p = 0.03) larger after GPi DBS (93%) than after STN DBS (83%). Also, the total amount of electrical energy delivered was significantly (p = 0.008) lower with STN DBS than with GPi DBS (124 ± 52 vs 192 ± 65 µJ, respectively). CONCLUSIONS: The GPi and STN are both effective targets in alleviating dystonia and improving quality of life. However, GPi stimulation may be better for patients with axial symptoms. Moreover, STN stimulation may produce a larger clinical response within 1 month after surgery and may have a potential economic advantage in terms of lower battery consumption.