Systems Neuroscience's 2022 Top Papers: An Editorial Summary.

Despite the seemingly endless-and sometimes overwhelming-flow of scientific information, there are always some articles that stand out from the crowd, either due to the depth of the covered topic, or due to their unique and unexpected findings [...].

Magnetic resonance imaging of radiofrequency thalamotomy for tremor: what is it about?

This scientific commentary refers to 'Radiofrequency thalamotomy for tremor produces focused and predictable lesions shown on magnetic resonance images', by Ishihara et al. (https://doi.org/10.1093/braincomms/fcad329).

Invasive Neuromodulation Techniques for Treatment-Resistant Depression.

Surgically implanted neurostimulation devices for the treatment of depression have been studied for the last three decades. While the surgical risk associated with these treatment approaches clearly limits their use to the most severely impacted depressed patients, they offer a unique opportunity to better understand the impact of relatively localized alteration of neural activity in patient groups. As a result, these approaches provide a strict test of the role of individual neural structures or networks in mechanistic models of depression. In this chapter, we review the proposed mechanisms of action and evidence for clinical efficacy of vagal nerve stimulation, deep brain stimulation, and epidural cortical stimulation in patients with depression. The evidence for efficacy remains limited for all three modalities, but the long-term follow-up studies of treated patients have highlighted the importance of interactions between neural regions in determining therapeutic response, and suggest that personalized approaches to stimulation are likely to be required.

Drug-Free Noninvasive Thermal Nerve Block: Validation of Sham Devices.

Headache is a leading cause of disability and suffering. One major challenge in developing device treatments is demonstrating their efficacy given devices' often-high placebo rate. This paper reviews the importance of validating sham devices as part of finalizing the design for larger-scale prospective randomized controlled trials in patients with chronic headache as well as the results of a prospective, single-blind trial to validate two potential sham noninvasive thermal nerve block devices. Study participants were trained to self-administer thermal nerve block treatment using sham devices in an office visit. Two different sham systems with different temperature profiles were assessed. Devices were offered for patients to use daily at-home for one week to assess the durability of sham placebo effects before participants were given active treatment in a second office visit followed by another optional week of self-administered active treatment at-home use. Sham treatments reduced pain scores by an average of 31% from 6.0 ± 2.3 to 4.3 ± 3.3, including two participants who fell asleep during the in-office treatment and woke up with no pain, but whose pain recurred after returning home during at-home use of the sham system. In-office active treatments reduced pain scores by 52% from 6.7 ± 2.1 to 3.3 ± 2.9 with sustained pain relief during optional at-home use. Successful blinding for the study was confirmed with an ideal Bang's Blinding Index of 0 and an ideal James' Blinding Index of 1. Both the sham and active treatments were viewed by participants as highly credible, and credibility increased from the beginning to end of sham treatments on average.

Open and Percutaneous Trigeminal Nucleotractotomy: A Case Series and Literature Review.

INTRODUCTION: Nucleotractotomy is an efficient surgical technique that provides a high pain relief rate for specific clinical indications. There are two main approaches for performing this operation: an open and percutaneous technique. METHODS: In the Federal Center of Neurosurgery (Novosibirsk, Russia) from 2016 to 2022, 13 trigeminal nucleotractotomies (7 open and 6 percutaneous) were performed in 12 patients (5 women and 7 men). The indications for surgery were deafferentation pain and chronic drug-resistant pain syndrome caused by malignancy in the facial region. A neurological examination was done on each patient 1 day before the surgery, right after the surgery, and at the follow-up (examinations were done after 1, 6, and 12 months, or when the patient independently applied to our hospital). In the early postoperative period, patients underwent brain MRI. RESULTS: The average pain intensity score before nucleotractotomy on the 11-point (0-10) visual analog scale (VAS) was 9.3. The effectiveness of open interventions was somewhat higher; the average VAS score in the early postoperative period for the open technique was 1.57, in the group of patients who underwent percutaneous nucleotractotomy were 2.66. Complete regression of the pain syndrome was achieved in 6 patients; in 5 patients, the pain in the face decreased by more than 50%. One case had an unsatisfactory outcome. In the open-surgery group in the early postoperative period, according to MRI, the average length of the visualized area of signal change was longer (21.5 mm, the average diameter was 3.75 mm) than in a percutaneous nucleotractotomy group (16 mm, the average diameter was 3.75 mm). During the postoperative period (average follow-up 40 months), the pain recurred in 3 patients (30%): 2 patients after percutaneous nucleotractotomy (3 and 18 months after surgery) and in 1 patient 4 months after the open surgery. The mean VAS score at the last follow-up was 2.6. CONCLUSION: Trigeminal nucleotractotomy is an effective approach to the treatment of intractable facial pain. Our experience suggests this technique is highly effective in patients with drug-resistant pain caused by craniofacial tumors and deafferentation conditions after treating trigeminal neuralgia.

Report of the third international Siberian neurosurgical conference (Sibneuro 22): Scientific and professional exchange in the heart of Siberia.

We present a summary of the recently held Third International Siberian Neurosurgical Conference (Sibneuro 22). Professional education, scientific exchange, and social interactions are essential in neurosurgical practice. In addition to the main program of the Congress, there were two practical pre-meeting courses: on aneurysm clipping and on intraoperative neuromonitoring. In addition, there was a 1-day seminar focusing on a role of laboratory diagnostics in neurosurgical practice. Within the framework of the Siberian Congress, there was a session devoted to inventions in neurosurgery, a rare subject of discussion at neurosurgical events. Our educational event is very important for the Siberian neurosurgery. Neurosurgeons of Siberia are a part of the world neurosurgical family. We not only try providing high-quality neurosurgical care to patients but also maintaining the academic level of education and scientific activity. The next - fourth - Siberian Neurosurgical Congress will take place in July 2024 in Irkutsk.

Remote Management of Spinal Cord Stimulation Devices for Chronic Pain: Expert Recommendations on Best Practices for Proper Utilization and Future Considerations.

OBJECTIVE: Emerging spinal cord stimulation (SCS) remote monitoring and programming technologies provide a unique opportunity to address challenges of in-person visits and improve patient care, although clinical guidance on implementation is needed. The goal of this document is to establish best clinical practices for integration of remote device management into the care of patients with SCS, including remote monitoring and remote programming. MATERIALS AND METHODS: A panel of experts in SCS met in July 2022, and additional experts contributed to the development of recommendations after the meeting via survey responses and correspondence. RESULTS: Major goals of remote SCS device management were identified, including prompt identification and resolution of SCS-related issues. The panel identified metrics for remote monitoring and classified them into three categories: device-related (eg, stimulation usage); measurable physiologic or disease-related (eg, patient physical activity or pedometry); and patient-reported (eg, sleep quality and pain intensity). Recommendations were made for frequency of reviewing remote monitoring metrics, although providers should tailor follow-up to individual patient needs. Such periodic reviews of remote monitoring metrics would occur separately from automatic monitoring system notifications (if key metrics fall outside an acceptable range). The guidelines were developed in consideration of reimbursement processes, privacy concerns, and the responsibilities of the care team, industry professionals, manufacturers, patients, and caregivers. Both existing and needed clinical evidence were covered, including outcomes of interest for future studies. CONCLUSIONS: Given the expansion of SCS device capabilities, this document provides critical guidance on best practices for using remote device management, although medical necessity should drive all remote monitoring decisions, with individualized patient care. The authors also describe the potential of these emerging technologies to improve outcomes for patients with SCS, although more clinical evidence is needed.

Detection of SARS-CoV-2 RNA by In Situ Hybridization in Lung-Cancer Cells Metastatic to Brain and in Adjacent Brain Parenchyma.

The mechanisms by which severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) may spread to the human brain are poorly understood, and the infection of cancer cells in the brain by SARS-CoV-2 in Coronavirus disease 2019 (COVID-19) patients has been the subject of only one previous case report. Here, we report the detection of SARS-CoV-2 RNA by in situ hybridization in lung-cancer cells metastatic to the brain and adjacent brain parenchyma in a 63-year-old male patient with COVID-19. These findings suggest that metastatic tumors may transport the virus from other parts of the body to the brain or may break down the blood-brain barrier to allow for the virus to spread to the brain. These findings confirm and extend previous observations that cancer cells in the brain can become infected by SARS-CoV-2 in patients with COVID-19 and raise the possibility that SARS-CoV-2 can have a direct effect on cancer growth and outcome.

Applications of brain-computer interfaces in neurodegenerative diseases.

Brain-computer interfaces (BCIs) provide the central nervous system with channels of direct communication to the outside world, without having to go through the peripheral nervous system. Neurodegenerative diseases (NDs) are notoriously incurable and burdensome medical conditions that will result in progressive deterioration of the nervous system. The applications of BCIs in NDs have been studied for decades now through different approaches, resulting in a considerable amount of literature in all related areas. In this study, we begin by introducing BCIs and proceed by explaining the principles of BCI-based neurorehabilitation. Then, we go through four specific types of NDs, including amyotrophic lateral sclerosis, Parkinson's disease, Alzheimer's disease, and spinal muscular atrophy, and review some of the applications of BCIs in the neural rehabilitation of these diseases. We conclude with a discussion of the characteristics, challenges, and future possibilities of research in the field. Going through the uses of BCIs in NDs, we can see that approaches and strategies employed to tackle the wide range of limitations caused by NDs are numerous and diverse. Furthermore, NDs can fall under different categories based on the target area of neurodegeneration and thus require different methods of BCI-based rehabilitation. In recent years, neurotechnology companies have substantially invested in research on BCIs, focusing on commercializing BCIs and bringing BCI-based technologies from bench to bedside. This can mean the beginning of a new era for BCI-based neurorehabilitation, with an anticipated spike in interest among researchers, practitioners, engineers, and entrepreneurs alike.

Evaluation of External Trigeminal Nerve Stimulation to Prevent Cerebral Vasospasm after Subarachnoid Hemorrhage Due to Aneurysmal Rupture: A Randomized, Double-Blind Proof-of-Concept Pilot Trial (TRIVASOSTIM Study).

Cerebral vasospasm remains the most frequent and devastating complication after subarachnoid aneurysmal hemorrhage because of secondary cerebral ischemia and its sequelae. The underlying pathophysiology involves vasodilator peptide release (such as CGRP) and nitric oxide depletion at the level of the precapillary sphincters of the cerebral (internal carotid artery network) and dural (external carotid artery network) arteries, which are both innervated by craniofacial autonomic afferents and tightly connected to the trigeminal nerve and trigemino-cervical nucleus complex. We hypothesized that trigeminal nerve modulation could influence the cerebral flow of this vascular network through a sympatholytic effect and decrease the occurrence of vasospasm and its consequences. We conducted a prospective double-blind, randomized controlled pilot trial to compare the effect of 10 days of transcutaneous electrical trigeminal nerve stimulation vs. sham stimulation on cerebral infarction occurrence at 3 months. Sixty patients treated for aneurysmal SAH (World Federation of Neurosurgical Societies scale between 1 and 4) were included. We compared the radiological incidence of delayed cerebral ischemia (DCI) on magnetic resonance imaging (MRI) at 3 months in moderate and severe vasospasm patients receiving trigeminal nerve stimulation (TNS group) vs. sham stimulation (sham group). Our primary endpoint (the infarction rate at the 3-month follow-up) did not significantly differ between the two groups (p = 0.99). Vasospasm-related infarctions were present in seven patients (23%) in the TNS group and eight patients (27%) in the sham group. Ultimately, we were not able to show that TNS can decrease the rate of cerebral infarction secondary to vasospasm occurrence. As a result, it would be premature to promote trigeminal system neurostimulation in this context. This concept should be the subject of further research.

A Retrospective Review of Real-world Outcomes Following 60-day Peripheral Nerve Stimulation for the Treatment of Chronic Pain.

BACKGROUND: Real-world data can provide important insights into treatment effectiveness in routine clinical practice. Studies have demonstrated that in multiple different pain indications temporary (60-day) percutaneous peripheral nerve stimulation (PNS) treatment can produce significant relief, but few real-world studies have been published. The present study is the first real-world, retrospective review of a large database depicting outcomes at the end of a 60-day PNS treatment period. OBJECTIVES: Evaluate outcomes during a 60-day PNS treatment in routine clinical practice. STUDY DESIGN: Secondary retrospective review. METHODS: Anonymized records of 6,160 patients who were implanted with a SPRINT PNS System from August 2019 through August 2022 were retrospectively reviewed from a national real-world database. The percentage of patients with ? 50% pain relief and/or improvement in quality of life was evaluated and stratified by nerve target. Additional outcomes included average and worst pain score, patient-reported percentage of pain relief, and patient global impression of change. RESULTS: Overall, 71% of patients (4,348/6,160) were responders with >= 50% pain relief and/or improvement in quality of life; pain relief among responders averaged 63%. The responder rate was largely consistent across nerve targets throughout the back and trunk, upper and lower extremities, and posterior head and neck. LIMITATIONS: This study was limited by its retrospective nature and reliance on a device manufacturer's database. Additionally, detailed demographic information and measures for pain medication usage and physical function were not assessed. CONCLUSIONS: This retrospective analysis supports recent prospective studies demonstrating that 60-day percutaneous PNS can provide significant relief across a wide range of nerve targets. These data serve an important role in complementing the findings of published prospective clinical trials.

Application of Vagus Nerve Stimulation in Spinal Cord Injury Rehabilitation.

Spinal cord injury (SCI) is a prevalent devastating condition causing significant morbidity and mortality, especially in developing countries. The pathophysiology of SCI involves ischemia, neuroinflammation, cell death, and scar formation. Due to the lack of definitive therapy for SCI, interventions mainly focus on rehabilitation to reduce deterioration and improve the patient's quality of life. Currently, rehabilitative exercises and neuromodulation methods such as functional electrical stimulation, epidural electrical stimulation, and transcutaneous electrical nerve stimulation are being tested in patients with SCI. Other spinal stimulation techniques are being developed and tested in animal models. However, often these methods require complex surgical procedures and solely focus on motor function. Vagus nerve stimulation (VNS) is currently used in patients with epilepsy, depression, and migraine and is being investigated for its application in other disorders. In animal models of SCI, VNS significantly improved locomotor function by ameliorating inflammation and improving plasticity, suggesting its use in human subjects. SCI patients also suffer from nonmotor complications, including pain, gastrointestinal dysfunction, cardiovascular disorders, and chronic conditions such as obesity and diabetes. VNS has shown promising results in alleviating these conditions in non-SCI patients, which makes it a possible therapeutic option in SCI patients.