Stereotactic and Functional Neurosurgery最新文献

Introduction: Intraoperative microelectrode recording (MER) is a widely employed technique for the physiological identification of the subthalamic nucleus (STN) during deep brain stimulation (DBS) surgery targeting the STN. However, failure to detect typical STN activity may raise concerns about diagnostic accuracy and treatment efficacy. Objective of this study were to retrospectively evaluate the clinical characteristics and long-term outcomes of patients with advanced Parkinson's disease (PD) in whom STN neuronal activity was not detected during intraoperative MER and to explore the implications of this finding for differential diagnosis and DBS candidacy.

Methods: Among 624 STN-DBS procedures performed at Juntendo University Hospital between 2012 and 2024, we identified 3 patients (0.5%) in whom intraoperative MER failed to detect typical STN neuronal activity. Clinical records were reviewed retrospectively, including demographic data, levodopa responsiveness, preoperative images, intraoperative MER findings, surgical decision-making processes, and postoperative clinical courses.

Results: All 3 patients were male, in their 60s at the time of surgery, with disease durations ranging from 5 to 7 years. Cognitive function was preserved in all cases. Gait disturbance was a prominent early symptom, and all patients experienced relatively early wearing-off phenomena. None exhibited dyskinesia, yet all showed good responsiveness to levodopa, confirmed by preoperative levodopa challenge tests. Despite multiple MER trajectories, no characteristic STN neuronal firing patterns were observed. DBS electrodes were implanted according to the initial surgical plan in 2 cases; in the other case, implantation was aborted. Following surgery, all patients demonstrated progressive axial motor deterioration. Based on their clinical course and imaging findings, all were ultimately diagnosed with or strongly suspected to have progressive supranuclear palsy-parkinsonism (PSP-P).

Conclusions: The absence of detectable STN activity during intraoperative MER may reflect underlying neurodegenerative pathology distinct from idiopathic PD, such as PSP-P. These findings suggest that MER, beyond its role in anatomical targeting, may serve as a valuable intraoperative biological indicator for diagnostic refinement. Even within a multidisciplinary setting led by movement disorder specialists, distinguishing PD from PSP-P prior to surgery remains a significant challenge. Improved diagnostic accuracy is critical to optimize patient selection for DBS and to prevent ineffective or potentially deleterious interventions.

Introduction: Trigeminal schwannomas (TSs) are rare benign tumors arising from the trigeminal nerve. Gamma Knife radiosurgery (GKS) offers a minimally invasive alternative to surgical resection, but the long-term clinical outcomes, particularly regarding change of trigeminal nerve function, remain under-characterized. This study aimed to evaluate long-term clinical outcomes and identify prognostic factors for neurological sequelae following primary GKS for TS.

Methods: A retrospective analysis was performed on 89 patients who underwent primary GKS for TS between 2002 and 2023. Patients with prior surgery or hypofractionation were excluded. Clinical and imaging data were analyzed for tumor control, symptom relief, and new-onset, or persistent post-GKS morbidities. Symptoms were classified as new-onset transient, new-onset permanent, or persistent preexisting. The Kaplan-Meier analysis, Logistic regression, and Cox regression were used to identify prognostic factors.

Results: Over a median follow-up of 57 months (range, 6.8-184), tumor control was 93.3%. Symptom relief occurred in 46.9% of preexisting deficits, highest for headache (70.6%) and dizziness (100%), but modest for trigeminal pain (33.3%) and paresthesia (36.7%). New-onset morbidities included trigeminal sensory disturbance (33.7%, permanent in 15) and pain (22.5%, permanent in 5). In Cox analysis, higher margin dose reduced the hazard of new paresthesia (HR 0.511, p = 0.036), while older age increased risk (HR 1.041, p = 0.037).

Conclusion: Primary GKS achieves durable tumor control for TS with lower risk than microsurgery. However, a considerable proportion of patients may experience long-term trigeminal dysfunction. Adequate dosing may mitigate sensory morbidity, though pain relief remains modest. Careful selection, counseling, and follow-up are essential.

Introduction: Bilateral electrode implantation is the primary approach for deep brain stimulation (DBS) in Parkinson's disease (PD). However, it may lead to gait deterioration in some patients. This study aimed to investigate the efficacy of unilateral DBS on gait in PD patients as an alternative with fewer side effects and lower costs.

Methods: We systematically searched four major clinical databases to evaluate the effects of unilateral DBS on UPDRS gait score, gait velocity, stride length, cadence, and gait initiation in PD patients. Twenty-three studies were included in the review, selected from an initial pool of 2,415 studies. We also performed a meta-analysis to assess the impact of unilateral DBS on gait velocity and compare its efficacy to bilateral stimulation. The study protocol was registered at PROSPERO with the registration code: CRD42024585359.

Results: The included studies assessed gait measures in patients receiving unilateral DBS targeting the STN, globus pallidus internus, pedunculopontine nucleus, and ventral intermediate nucleus. According to the systematic review of clinical evidence, unilateral DBS can improve the UPDRS gait score, freezing of gait, and gait velocity, although to a lesser extent than bilateral stimulation. The meta-analysis revealed a nonsignificant positive pooled effect on gait velocity in the unilateral DBS condition compared to the control condition and no significant difference when compared to bilateral DBS.

Conclusion: Unilateral DBS shows promise for improving gait in PD, as an alternative with lower costs and side effects, especially in early-stage or asymmetric cases.

Background: Deep brain stimulation (DBS) is a well-established treatment for several neurological and neuropsychiatric conditions, including movement disorders such as Parkinson's disease, essential tremor, and dystonia, as well as Gilles de la Tourette's syndrome, epilepsy, and obsessive-compulsive disorder.

Summary: In recent years, research has expanded to explore the potential of DBS for other indications, including dementia, addiction, disorders of consciousness (e.g., minimally conscious state), and eating disorders. Over the past 3 decades, significant technological advancements have been made in DBS devices, including improvements in electrode design, stimulation parameters, and battery life. However, despite these technological innovations, equitable access to DBS has not progressed at a similar pace. Barriers to access remain a persistent challenge globally, influenced by socioeconomic, geographic, systemic, and policy-related factors.

Key message: This review summarizes the current literature on access to DBS, highlighting disparities, challenges, and potential strategies to improve availability and equity in its application.

Background Radiofrequency lesioning (RL) had been a mainstay in functional neurosurgery for dystonic movement disorders before the widespread adoption of deep brain stimulation (DBS). Outcomes of RL in hemidystonia have varied. This review provides a systematic analysis of RL for hemidystonia and evaluates the spectrum of clinical outcome. Methods A systematic literature review was performed according to PRISMA guidelines in PubMed, Embase, and Web of Science using a customized software (UiPath, NY) to identify all case reports, case series, and cohort studies reporting patients with hemidystonia treated with RF. Manuscripts were automatically searched for the term "hemidystonia". The selected manuscripts were then manually screened. Detailed information from two recent multi-patient studies was added. Clinical improvement was classified as follows: (0) no improvement; (I) mild; (II) moderate; (III) marked improvement. Results Twenty-eight studies with individual patient data were included, totaling 101 cases published between 1962 and 2024. Thalamotomy was performed in 80 cases, pallidotomy in 16, and both in 5. At last follow-up, 18 patients (19.35%) showed marked improvement, 41 (44.09%) moderate, 16 (17.21%) mild, and 18 (19.35%) no benefit. No significant differences in outcomes were found between targets or etiologies, though patients with traumatic brain injury tended to fare worse. A significant negative linear correlation was found between the degree of improvement and age at surgery. Conclusion With advancements in targeting and technology, RL may be reconsidered as a treatment option for hemidystonia. Further studies with standardized outcome assessments are needed to better characterize response variability and identify prognostic factors.

Stereotactic anterior cingulotomy is a neurosurgical technique that can offer significant pain relief in patients with refractory cancer pain, particularly in the palliative setting. Despite being described in the 1960s, its use has recently resurged due to limitations of pharmacologic and neuromodulatory therapies in terminally ill patients. The anterior cingulate cortex plays a crucial role in the affective processing of pain, and its disruption through targeted lesioning may reduce suffering without eliminating nociception. This review summarises the historical background, patient selection criteria, surgical approaches, efficacy data, and safety outcomes associated with bilateral anterior cingulotomy for cancer-related pain. Additionally, the Queen Square approach, incorporating MRI-guided targeting and diffusion imaging, is described. Available data support the procedure's short-term efficacy in the majority of patients, with limited cognitive side effects and minimal morbidity. Future directions include network-based targeting, refinement of lesion techniques, and consideration of non-invasive alternatives such as focused ultrasound. Further research is warranted to optimise selection criteria and understand the neural mechanisms underlying pain relief.

Background: Psychiatric neurosurgery has been shaped by an ethically complex history and rapid evolution in neurotechnology. In the modern era, there is a growing need to match the accelerating pace of scientific innovation with rigorous, contemporary ethical frameworks that prioritize patient autonomy, safety, and maintaining public trust.

Summary: In this article, we review 21st-century approaches to neurosurgery for psychiatric disorders that combine the precision of modern functional neurosurgery with advances in diagnostic and therapeutic neurotechnology. The ethical issues in contemporary psychiatric neurosurgery are multifaceted and evolving, reflecting the intersection of rapid scientific progress, changing societal values, and a controversial past.

Key messages: The four core principles of medical ethics - beneficence, nonmaleficence, autonomy, and justice - and their application to psychiatric neurosurgery are discussed in the context of existing and anticipated ethical issues (e.g., post-trial responsibilities in research, informed consent, disparities in access to care). Finally, we explore how technological breakthroughs, coupled with growing market investment and consumer interest in the field, establish a compelling need to develop robust, forward-looking regulatory frameworks that are aligned with these bioethical principles.

Surgical treatment of generalized drug-resistant epilepsy (DRE), lacking a clearly resectable epileptogenic focus, presents a formidable clinical challenge. Inadequately treated generalized DRE is associated with neurological deficits, impaired neurodevelopment, poor quality of life, and lifelong educational and occupational difficulties. Over the last half-century, various neurosurgical interventions have been introduced for the management of generalized DRE. These include longstanding and well-established disconnection procedures, which have evolved over time to reduce surgical morbidity, as well as more recent options such as neuromodulation through surgically implanted devices. As technological advances and evidence for their use continues to grow, clinical decision-making has become increasingly nuanced. In this article, we review contemporary neurosurgical approaches for managing generalized DRE, including the most common disconnection and neuromodulation-based interventions, and provide a framework to guide patient selection and presurgical counselling at specialized epilepsy centers. We conclude with an overview of current and emerging technological advances in this rapidly evolving field, providing an up-to-date resource for clinicians to inform practice.

Background Long-term/low grade epilepsy-associated tumors (LEATs) compose a complex group of low-grade brain neoplasms associated with drug-resistant focal epilepsy, primarily affecting pediatric and adolescent populations. LEATs exhibit significant epileptogenic potential, profoundly impacting patients' neurological and psychosocial outcomes. Advances in molecular pathology, particularly the identification of BRAF V600E and FGFR1 mutations, have enhanced the classification and understanding of these tumors, opening potential avenues for targeted therapies. Summary This review synthesizes current knowledge on LEAT biology, epileptogenesis, and clinical manifestations, highlighting the tumor microenvironment's role in seizure generation through disrupted neurotransmitter signaling, inflammatory processes, and network hyperexcitability. The integration of advanced neuroimaging, electrophysiology, and molecular diagnostics has refined LEAT detection and classification, improving surgical decision-making. Surgical resection remains the mainstay of treatment, with seizure freedom rates exceeding 80% when combined with tailored epilepsy surgery. However, variability in surgical outcomes underscores the need for individualized approaches, incorporating emerging minimally invasive techniques, such as laser interstitial thermal therapy (LITT), and neuromodulation strategies. Key Messages Despite advancements in the diagnosis and treatment of LEATs, key challenges remain, including refractory epilepsy, malignant progression, and the long-term impact of LEATs on cognitive function. Future research aims to refine the molecular and histopathological classification of LEATs, develop predictive biomarkers for seizure outcomes, and explore precision therapies targeting tumor-associated epileptogenesis. As the field evolves, a multidisciplinary approach integrating surgery, molecular therapeutics, and neurorehabilitation will be essential in optimizing patient outcomes.

Introduction: Photon-counting detector computed tomography (PCD-CT) represents the next generation of CT technology, offering enhanced capabilities for detecting the orientation of directional leads in deep brain stimulation (DBS). This study aims to refine PCD-CT-based lead orientation determination using an automated method applicable to devices from various manufacturers, addressing current methodological limitations and improving neurosurgical precision.

Methods: An automated method was developed to ascertain the orientation of directional DBS leads using PCD-CT data and grayscale model fitting for devices from Boston Scientific, Medtronic, and Abbott. A phantom study was conducted to evaluate the precision and accuracy of this method, comparing it with the stripe artifact method across different lead alignments relative to the CT gantry axis.

Results: Except for the Medtronic Sensight™ lead, where detection was occasionally unfeasible if aligned normal to the z-axis of the CT gantry, a clinically very unlikely alignment, the lead orientation could be automatically determined regardless of its position. The accuracy and precision of this automated method was comparable to those of the stripe artifact method.

Conclusion: PCD-CT enables the automatic determination of lead orientation from leading manufacturers with an accuracy comparable to the stripe artifact method, and it offers the added benefit of being independent of the clinically occurring orientation of the head and, consequently, the lead relative to the CT gantry axis.