Variation Minimization Based Electrocardiogram Artifacts Removal for Local Field Potentials From Neurostimulator.

Local field potential (LFP) recorded by sensing-enabled neurostimulators provided chronic observation of deep brain activities for the research of brain disorders. However, the contamination from the electrocardiogram (ECG) deteriorated the extraction of effective information from LFP. This study proposed a novel algorithm based on minimizing the variance combining template subtraction to improve the performance of ECG artifact removal for LFP. Four patients with implanted electrodes were recruited, and eight real LFP records were collected from their left and right hemispheres, respectively. The results showed that the proposed method improved the accuracy of artifact peak detection in LFP, and the subsequent signal quality after template subtraction compared to the traditional Pan-Tompkins (PT) method. The outcome of this study benefited the LFP-based brain research, promoting the application of sensing-enabled neurostimulators in more areas.

Spinal cord stimulation and deep brain stimulation for disorders of consciousness: a systematic review and individual patient data analysis of 608 cases.

The application of spinal cord stimulation (SCS) and deep brain stimulation (DBS) for disorders of consciousness (DoC) has been increasingly reported. However, there is no sufficient evidence to determine how effective and safe SCS and DBS are for DoC owing to various methodological limitations. We conducted a systematic review to elucidate the safety and efficacy of SCS and DBS for DoC by systematically reviewing related literature by searching PubMed, EMBASE, Medline, and Cochrane Library. Twenty eligible studies with 608 patients were included in this study. Ten studies with 508 patients reported the efficacy of SCS for DoC, and the estimated overall effectiveness rate was 37%. Five studies with 343 patients reported the efficacy of SCS for VS, and the estimated effectiveness rate was 30%. Three studies with 53 patients reported the efficacy of SCS for MCS, and the estimated effectiveness rate was 63%. Five studies with 92 patients reported the efficacy of DBS for DoC, and the estimated overall effectiveness rate was 40%. Four studies with 63 patients reported the efficacy of DBS for VS, and the estimated effectiveness rate was 26%. Three studies with 19 patients reported the efficacy of DBS for MCS, and the estimated effectiveness rate was 74%. The adverse event rate of DoC was 8.1% and 18.2% after SCS and DBS, respectively. These results suggest that SCS and DBS can be considered reasonable treatments for DoC with considerable efficacy and safety.

Gamma Knife surgery and deep brain stimulation of the centromedian nucleus for chronic pain: A systematic review.

Chronic pain has been a major problem in personal quality of life and social economy, causing psychological disorders in people and a larger amount of money loss in society. Some targets were adopted for chronic pain, but the efficacy of the CM nucleus for pain was still unclear. A systematic review was performed to summarize GK surgery and DBS of the CM nucleus for chronic pain. PubMed, Embase and Medline were searched to review all studies discussing GK surgery and DBS on the CM nucleus for chronic pain. Studies that were review, meet, conference, not English or not the therapy of pain were excluded. Demographic characteristics, surgery parameters and outcomes of pain relief were selected. In total, 101 patients across 12 studies were included. The median age of most patients ranged from 44.3 to 80 years when the duration of pain ranged from 5 months to 8 years. This review showed varied results of 30%-100% pain reduction across studies. The difference in the effect between GK surgery and DBS cannot be judged. Moreover, three retrospective articles related to GK surgery of the CM nucleus for trigeminal neuralgia presented an average pain relief rate of 34.6-82.5%. Four studies reported adverse effects in a small number of patients. GK surgery and DBS of the CM nucleus might be promising therapeutic approaches for chronic refractory pain. More rigorous studies and larger samples with longer follow-up periods are needed to support the effectiveness and safety.

Local field potentials in major depressive and obsessive-compulsive disorder: a frequency-based review.

Objectives: The purpose of this paper is to provide a mini-review covering the recent progress in human and animal studies on local field potentials (LFPs) of major depressive disorder (MDD) and obsessive-compulsive disorder (OCD). Materials and methods: PubMed and EMBASE were searched to identify related studies. Inclusion criteria were (1) reported the LFPs on OCD or MDD, (2) published in English, and (3) human or animal studies. Exclusion criteria were (1) review or meta-analysis or other literature types without original data and (2) conference abstract without full text. Descriptive synthesis of data was performed. Results: Eight studies on LFPs of OCD containing 22 patients and 32 rats were included: seven were observational studies with no controls, and one animal study included a randomized and controlled phase. Ten studies on LFPs of MDD containing 71 patients and 52 rats were included: seven were observational studies with no controls, one study with control, and two animal studies included a randomized and controlled phase. Conclusion: The available studies revealed that different frequency bands were associated with specific symptoms. Low frequency activity seemed to be closely related to OCD symptoms, whereas LFPs findings in patients with MDD were more complicated. However, limitations of recent studies restrict the drawing of definite conclusions. Combined with other measures such as Electroencephalogram, Electrocorticography, or Magnetoencephalography and long-term recordings in various physiological states (rest state, sleep state, task state) could help to improve the understanding of potential mechanisms.

Use of differential stimulation of the nucleus accumbens and anterior limb of the internal capsule to improve outcomes of obsessive-compulsive disorder.

OBJECTIVE: Personalized stimulation is key to optimizing the outcomes of deep brain stimulation (DBS) for refractory obsessive-compulsive disorder (OCD). However, the contacts in a single conventional electrode cannot be programmed independently, which may affect the therapeutic efficacy of DBS for OCD. Therefore, a novel designed electrode and implantable pulse generator (IPG) that could achieve differential stimulation parameters for different contacts was implanted into the nucleus accumbens (NAc) and anterior limb of the internal capsule (ALIC) of a cohort of patients with OCD. METHODS: Thirteen consecutive patients underwent bilateral DBS of the NAc-ALIC between January 2016 and May 2021. Differential stimulation of the NAc-ALIC was applied at initial activation. Primary effectiveness was assessed on the basis of change in scores on the Yale-Brown Obsessive Compulsive Scale (Y-BOCS) from baseline to 6-month follow-up. Full-response was defined as a 35% decrease in Y-BOCS score. Secondary effectiveness measures were the Hamilton Anxiety Rating Scale (HAMA) and Hamilton Depression Rating Scale (HAMD). The local field potential of bilateral NAc-ALIC was recorded in 4 patients who were reimplanted with a sensing IPG after battery depletion of the previous IPG. RESULTS: The Y-BOCS, HAMA, and HAMD scores decreased remarkably during the first 6 months of DBS. Ten of 13 patients were categorized as responders (76.9%). Differential stimulation of the NAc-ALIC was favorable to optimization of the stimulation parameters by increasing the parameter configurations. Power spectral density analysis revealed pronounced delta-alpha frequency activity in the NAc-ALIC. Phase-amplitude coupling of the NAc-ALIC showed that strong coupling is present between the phase of delta-theta and broadband gamma amplitude. CONCLUSIONS: These preliminary findings indicate that differential stimulation of the NAc-ALIC can improve the efficacy of DBS for OCD. Clinical trial registration no.: NCT02398318 (ClinicalTrials.gov).

Deep brain stimulation in Lesch-Nyhan syndrome: a systematic review.

Given the good results of deep brain stimulation (DBS) in the treatment of movement disorders, DBS was initially tried to treat Lesch-Nyhan syndrome (LNS) with the aim to alleviate LNS-related dystonia. Some cases have reported clinical results of DBS in LNS thus far. This systematic review was conducted to comprehensively summarize cases of LNS treated with DBS and evaluate the efficacy and safety of DBS in LNS. Eight publications covering 12 LNS patients were included in this review. DBS improved dystonia of the LNS to varying degrees. All the included cases achieved partial or complete control of self-injurious behavior (SIB). Overall, DBS is a promising treatment for both motor and behavior disorders of LNS patients, but the results reported thus far have varied widely, especially for motor outcomes. The ultimate clinical benefits in LNS patients were still unpredictable. DBS-related complications were rather common, which raised questions about the safety of the procedure in LNS. More research is needed to further clarify the safety and effectiveness of this treatment.

Stereotactic radiosurgery combined with immune checkpoint inhibitors for brain metastasis: A systematic review and meta-analysis.

Many studies have reported the combination of radiosurgery and immune checkpoint inhibitors (ICI) in the treatment of brain metastasis, but these studies have not reached a consistent conclusion. Therefore, we conducted this systematic review and meta-analysis to evaluate the effect of combination therapy compared with radiosurgery alone on the prognosis of patients with brain metastasis. The Pubmed-MEDLINE and Ovid-EMBASE databases were comprehensively searched to identify relevant articles until May 5, 2022. The search results were filtered by the inclusion and exclusion criteria described in this paper. The pooled hazard ratios (HR) with 95% confidence intervals (CI) were presented as estimates effect to reflect the effect of combined therapy on each outcome. A total of 17 eligible studies covering 2079 patients were included in this meta-analysis. The pooled results showed that the use of targeted drugs could significantly improve the overall survival (HR = 0.62, 95%CI: 0.51-0.76; P<0.01), reduce the risk of local recurrence (HR = 0.48, 95%CI: 0.38-0.62; P<0.01) and distant brain recurrence (HR = 0.70, 95%CI: 0.50-0.97; P<0.05). Overall, SRS combined with ICIs could significantly improve overall survival, local control, and distant brain control of patients with brain metastasis compared to SRS alone, but the effect varies for different pathological types. Our results verified the rationality of the current treatment strategy for brain metastasis which emphasizes the combination of local and systematic therapy.

Deep brain stimulation for chorea-acanthocytosis: a systematic review.

Deep brain stimulation (DBS) is a reversible treatment for chorea-acanthocytosis (ChAc). Its safety and efficacy remain elusive due to the low prevalence of ChAc. We aimed to investigate the safety and efficacy of DBS for ChAc by systematically reviewing literature through PubMed and EMBASE. Inclusion criteria were reports on the efficacy or safety of DBS for ChAc and English language articles, and exclusion criteria were other movement disorders, non-human subjects, and studies without original data. Most studies were published as case reports, and we therefore pooled these cases in one cohort. Twenty studies with 34 patients were included. The mean age of symptom onset was 29.3 years (range, 17-48). The median follow-up was 12 months (range, 2-84). Twenty-nine patients underwent GPi-DBS, two received STN-DBS, and one underwent Vop-DBS. Electrodes were implanted into the ventralis oralis complex of the thalamus and the pallidal in two patients. Symptoms seemed to be easier relieved in chorea (88.5%) and dystonia (76.9%) but dysarthria of most patients (85.7%) was no response after DBS. The Unified Huntington's Disease Rating Scale-Motor Score was used to assess the efficacy of DBS in 25 patients; the mean score decreased from 43.2 to 22.3 and the median improvement rate was 46.7%. Of 24 patients with data on adverse events, complications occurred in 9 patients (37.5%; mostly transient and mild events). DBS is a promising treatment for ChAc with satisfactory efficacy and safety based on the review. Pallidal and thalamic DBS have been applied in ChAc; GPi-DBS seems to be more widely used.

Safety and efficacy of magnetic resonance imaging-guided focused ultrasound neurosurgery for Parkinson's disease: a systematic review.

Magnetic resonance imaging-guided focused ultrasound (MRgFUS) neurosurgery is a new option for medication-resistant Parkinson's disease (PD), but its safety and efficacy remain elusive. This study aimed to investigate the safety and efficacy of MRgFUS for PD by systematically reviewing related literature. PubMed and EMBASE were searched to identify related studies. Inclusion criteria were (1) reported the efficacy or safety of MRgFUS for PD and (2) published in English. Exclusion criteria were (1) nonhuman study, (2) review or meta-analysis or other literature types without original data, and (3) conference abstract without full text. Data on study characteristics, treatment parameters, efficacy, and adverse events were collected. Descriptive synthesis of data was performed. Eleven studies containing 80 patients were included. Nine studies were observational studies with no controls. Two studies included a randomized and controlled phase. Most studies included tremor-dominant PD. Ten studies reported decline of UPDRS-III scores after MRgFUS, and five reported a statistically significant decline. Nine studies evaluated the quality of life (QOL). Significant improvement of QOL was reported by four studies using the 39-item Parkinson's disease questionnaire. Four studies investigated the impact of MRgFUS on non-motor symptoms. Most tests indicated that MRgFUS had no significant effect on neuropsychological outcomes. Most adverse events were mild and transient. MRgFUS is a potential treatment for PD with satisfying efficacy and safety. Studies in this field are still limited. More studies with strict design, larger sample size, and longer follow-up are needed to further investigate its efficacy and safety for PD.

Pineal Region Gliomas: A Single-Center Experience with 25 Cases.

BACKGROUND: Pineal region glioma is a rare systematically reported tumor in the literatures, and little is known about its behavior, development, and best treatment strategies because of its complex anatomical relationship and rarity. OBJECTIVE: We reviewed the outcomes of patients with pineal region gliomas in West China hospital in the past 5 years and searched the literature to add more information. As a result, key factors related to prognosis are identified. METHODS: Twenty-five patients with pineal region gliomas were selected and information was collected about detailed medical history, imaging data, treatment methods, pathologic results, and latest neurosurgical radiologic progress during follow-up. RESULTS: Pilocytic astrocytomas (20%) and glioblastomas (24%) were the most common pathologic subtypes. Twenty-three patients underwent open surgery, 3 Gamma Knife radiosurgery, and 4 whole-brain radiation therapy. Chemotherapy was applied to 3 patients. Low-grade gliomas tended to have a better prognosis than did high-grade. Karnofsky Performance Status at admission (≤60) was intimately associated with prognosis for low-grade gliomas. As for high-grade gliomas, patients whose age at admission was ≤30 years had a better prognosis than did older patients (＞30 years). However, whatever the grade, there was no overall survival difference as to gender, gross total resection versus not gross total resection, preoperative maximal tumor diameter (≤4 vs. ＞4 cm), and time since first symptoms (≤30 vs. ＞30 days), and radiation therapy versus no radiation therapy. CONCLUSIONS: Open surgery is the first-line strategy for pineal region gliomas with tolerable mortality and disability rate. Radiosurgery and chemotherapy can be applied as adjuvant or alternative methods when surgery is contraindicated.

The Suitability of Different Subtypes and Dimensions of Obsessive-Compulsive Disorder for Treatment with Anterior Capsulotomy: A Long-Term Follow-Up Study.

OBJECTIVE: Anterior capsulotomy (AC) is sometimes used as a life-saving treatment for patients with treatment-refractory obsessive-compulsive disorder (Tr-OCD). Most of the previous studies have assessed only total symptoms and have concluded that AC is a safe and effective procedure. Few of these studies have focused on meticulously investigating the variety of results obtained from patients with different subtypes of OCD. This study reviewed the long-term effects of AC on patients with OCD and analyzed the dissimilarity between particular subtypes of the disease in order to determine which groups are more suited to surgical treatment. METHODS: For this retrospective evaluation, we selected 54 consecutive patients from a total of 63 people with Tr-OCD between 2005 and 2014 who had undergone AC by thermocoagulation at our department. Preoperative and follow-up assessments were conducted at multiple time points (before surgery and 1, 3, 6, 12, and 36 months after surgery). The Yale-Brown Obsessive-Compulsive Scale (Y-BOCS), Hamilton Depression Scale (HAMD), and Hamilton Anxiety Scale (HAMA) were used to quantify the symptoms of OCD. According to different elements (clinical manifestation, comorbidity, and whether a patient was more compulsive or more obsessive), we classified patients into various subtypes and analyzed the variation in symptom improvement and adverse effects. RESULTS: The mean Y-BOCS, HAMD, and HAMA scores were, respectively, 27.03, 23.30, and 21.46 preoperatively and 8.50, 7.07, and 7.42, respectively, at 36 months after surgery. Most patients (n = 43, 79.6%) were shown to have been at least partially responsive to surgical treatment at their long-term follow-up. Six patients demonstrated no obvious improvement (Y-BOCS score decreased by <35%), and 5 patients developed recurrences of their conditions. The following subtypes demonstrated better results: contamination/cleaning; obsessions/checking; compulsive behavior dominant; pure OCD; and OCD with Tourette's -syndrome. The subtypes of aggressive/sexual, obsessive thought dominant, compulsive behavior with obsessive thoughts, OCD comorbidity with bipolar disorder, OCD comorbid with severe depression, and OCD comorbid with psychiatric symptoms showed good outcomes. However, surgery was ineffective for patients with the subtypes of symmetry/ordering, hoarding, pure obsessive thoughts, and OCD with obsessive slowness. CONCLUSIONS: AC is effective in reducing symptoms of OCD. By comparing differently classified follow-up results, we found that patients with most subtypes/dimensions of OCD showed good outcomes. How-ever, patients categorized into the OCD subtypes of pure -obsessive thoughts, symmetry/ordering, hoarding, OCD with obsessive slowness, and OCD comorbid with psychiatric symptoms should take into account these results before undergoing AC.

The Efficacy of Gamma Knife Radiosurgery for Cavernous Malformations: A Meta-Analysis and Review.

OBJECTIVE: This meta-analysis is to evaluate the clinical efficacy of gamma knife radiosurgery (GKRS) for treating cavernous malformations. METHODS: PubMed, Ovid Embase, and Ovid Medline electronic databases were searched. The primary outcome is hemorrhage rate and this meta-analysis is performed. RESULTS: Nine studies are included in this meta-analysis. The overall risk ratio (RR) of hemorrhage rate of pre-GKRS and post-GKRS is 6.08 (95% confidence interval [CI], 5.04-7.35). The overall RR is 3.03 (95% CI, 2.65-4.11) between the hemorrhage rate of pre-GKRS and the first 2 years postradiosurgery, and the overall RR is 12.13 (95% CI, 1.73-85.07) comparing pre-GKRS with 2 years after GKRS. There is no significant difference of the hemorrhage rate between the first 2 years postradiosurgery and 2 years after GKRS (RR = 2.81; 95% CI, 0.20-13.42). The neurologic deficiency is the most common radiosurgery-related complication. CONCLUSIONS: Patients with cerebral cavernous malformations, especially ones that were deep seated and surgically inaccessible, seem to benefit from GKRS owing to a reduction of annual hemorrhage rate in the first 2 years and 2 years after, despite several cases that suffer from negative side effects of radiation.