Improved Side-Effect Stimulation Thresholds and Postoperative Transient Confusion With Asleep, Image-Guided Deep Brain Stimulation.

Background And Objectives: Asleep, image-guided deep brain stimulation (DBS) is a modern alternative to awake, microelectrode recording (MER) guidance. Studies demonstrate comparable efficacy and complications between techniques, although some report lower stimulation thresholds for side effects with image guidance. In addition, few studies directly compare the risk of postoperative transient confusion (pTC) across techniques.

Reconnecting the Hand and Arm to the Brain: Efficacy of Neural Interfaces for Sensorimotor Restoration After Tetraplegia.

Background And Objectives: Paralysis after spinal cord injury involves damage to pathways that connect neurons in the brain to peripheral nerves in the limbs. Re-establishing this communication using neural interfaces has the potential to bridge the gap and restore upper extremity function to people with high tetraplegia. We report a novel approach for restoring upper extremity function using selective peripheral nerve stimulation controlled by intracortical microelectrode recordings from sensorimotor networks, along with restoration of tactile sensation of the hand using intracortical microstimulation.

Future directions in psychiatric neurosurgery: Proceedings of the 2022 American Society for Stereotactic and Functional Neurosurgery meeting on surgical neuromodulation for psychiatric disorders.

Objective: Despite advances in the treatment of psychiatric diseases, currently available therapies do not provide sufficient and durable relief for as many as 30-40% of patients. Neuromodulation, including deep brain stimulation (DBS), has emerged as a potential therapy for persistent disabling disease, however it has not yet gained widespread adoption. In 2016, the American Society for Stereotactic and Functional Neurosurgery (ASSFN) convened a meeting with leaders in the field to discuss a roadmap for the path forward.

Current Applications of Ablative Therapies for Trigeminal Neuralgia.

Trigeminal neuralgia (TN) is a syndrome consisting of episodic neuropathic facial pain. Although the precise symptoms vary across individuals, TN is typically described as lancinating electrical shocks triggered by sensory stimuli (light touch, talking, eating, and brushing teeth) that improve with antiepileptic medication (especially carbamazepine), remit spontaneously for weeks to months (pain-free intervals), and do not involve any changes in baseline sensation. The etiology of TN has not been definitively established, but many cases are associated with compression of the trigeminal nerve by a blood vessel at the trigeminal root entry zone adjacent to the brainstem.

Best practices for the pregnant neurosurgical resident: balancing safety and education.

Establishment of a diverse neurosurgical workforce includes increasing the recruitment of women in neurosurgery. The impact of pregnancy on the training and career trajectory of female neurosurgeons poses a barrier to recruitment and retention of women in neurosurgery. A recent Women in Neurosurgery survey evaluated female neurosurgeons' perception and experience regarding childbearing of female neurosurgeons and identified several recommendations regarding family leave policies.

Interim Safety Profile From the Feasibility Study of the BrainGate Neural Interface System.

Background And Objectives: Brain-computer interfaces (BCIs) are being developed to restore mobility, communication, and functional independence to people with paralysis. Though supported by decades of preclinical data, the safety of chronically implanted microelectrode array BCIs in humans is unknown. We report safety results from the prospective, open-label, nonrandomized BrainGate feasibility study (NCT00912041), the largest and longest-running clinical trial of an implanted BCI.

Cingulum bundle connectivity in treatment-refractory compared to treatment-responsive patients with bipolar disorder and healthy controls: a tractography and surgical targeting analysis.

Objective: The clinical response of patients with bipolar disorder to medical treatment is variable. A better understanding of the underlying neural circuitry involved in bipolar treatment responsivity subtypes may provide insight into treatment resistance and aid in identifying an effective surgical target for deep brain stimulation (DBS) specific to the disorder. Despite considerable imaging research related to the disease, a paucity of comparative imaging analyses of treatment responsiveness exists.

Pregnancy and parental leave among neurosurgeons and neurosurgical trainees.

Objective: Despite recently heightened advocacy efforts relating to pregnancy and family leave policies in multiple surgical specialties, no studies to date have described female neurosurgeons' experiences with childbearing. The AANS/CNS Section of Women in Neurosurgery created the Women and Pregnancy Task Force to ascertain female neurosurgeons' experiences with and attitudes toward pregnancy and the role of family leave policies.

Methods: A voluntary online 28-question survey examined the pregnancy experiences of female neurosurgeons and perceived barriers to childbearing.

Connectivity-based identification of a potential neurosurgical target for mood disorders.

Objective: Stereotactic ablation (cingulotomy) and subcallosal cingulate deep brain stimulation (SCC DBS) of different regions of the cingulum bundle (CB) have been successfully used to treat psychiatric disorders, such as depression and bipolar disorder. They are hypothesized to work by disrupting white matter pathways involved in the clinical manifestation of these disorders. This study aims to compare the connectivity of different CB subregions using tractography to evaluate stereotactic targets for the treatment of mood disorders.

Clinical Evaluation of Cingulum Bundle Connectivity for Neurosurgical Hypothesis Development.

Background: The cingulum bundle (CB) has long been a target for psychiatric neurosurgical procedures, but with limited understanding of the brain networks being impacted. Recent advances in human tractography could provide a foundation to better understand the effects of neurosurgical interventions on the CB; however, the reliability of tractography remains in question.

Objective: To evaluate the ability of different tractography techniques, derived from typical, human diffusion-weighted imaging (DWI) data, to characterize CB connectivity described in animal models.

Principled BCI Decoder Design and Parameter Selection Using a Feedback Control Model.

Decoders optimized offline to reconstruct intended movements from neural recordings sometimes fail to achieve optimal performance online when they are used in closed-loop as part of an intracortical brain-computer interface (iBCI). This is because typical decoder calibration routines do not model the emergent interactions between the decoder, the user, and the task parameters (e.g.

Evolution in the Treatment of Psychiatric Disorders: From Psychosurgery to Psychopharmacology to Neuromodulation.

The treatment of psychiatric patients presents significant challenges to the clinical community, and a multidisciplinary approach to diagnosis and management is essential to facilitate optimal care. In particular, the neurosurgical treatment of psychiatric disorders, or "psychosurgery," has held fascination throughout human history as a potential method of influencing behavior and consciousness. Early evidence of such procedures can be traced to prehistory, and interest flourished in the nineteenth and early twentieth century with greater insight into cerebral functional and anatomic localization.

A Comparison of Intention Estimation Methods for Decoder Calibration in Intracortical Brain-Computer Interfaces.

Objective: Recent reports indicate that making better assumptions about the user's intended movement can improve the accuracy of decoder calibration for intracortical brain-computer interfaces. Several methods now exist for estimating user intent, including an optimal feedback control model, a piecewise-linear feedback control model, ReFIT, and other heuristics. Which of these methods yields the best decoding performance?

Methods: Using data from the BrainGate2 pilot clinical trial, we measured how a steady-state velocity Kalman filter decoder was affected by the choice of intention estimation method.

Congress of Neurological Surgeons Systematic Review and Evidence-Based Guideline on Subthalamic Nucleus and Globus Pallidus Internus Deep Brain Stimulation for the Treatment of Patients With Parkinson's Disease: Executive Summary.

Question 1: Is bilateral subthalamic nucleus deep brain stimulation (STN DBS) more, less, or as effective as bilateral globus pallidus internus deep brain stimulation (GPi DBS) in treating motor symptoms of Parkinson's disease, as measured by improvements in Unified Parkinson's Disease Rating Scale, part III (UPDRS-III) scores?

Recommendation: Given that bilateral STN DBS is at least as effective as bilateral GPi DBS in treating motor symptoms of Parkinson's disease (as measured by improvements in UPDRS-III scores), consideration can be given to the selection of either target in patients undergoing surgery to treat motor symptoms. (Level I).

Question 2: Is bilateral STN DBS more, less, or as effective as bilateral GPi DBS in allowing reduction of dopaminergic medication in Parkinson's disease?

Recommendation: When the main goal of surgery is reduction of dopaminergic medications in a patient with Parkinson's disease, then bilateral STN DBS should be performed instead of GPi DBS.

Rapid calibration of an intracortical brain-computer interface for people with tetraplegia.

Objective: Brain-computer interfaces (BCIs) can enable individuals with tetraplegia to communicate and control external devices. Though much progress has been made in improving the speed and robustness of neural control provided by intracortical BCIs, little research has been devoted to minimizing the amount of time spent on decoder calibration.

Approach: We investigated the amount of time users needed to calibrate decoders and achieve performance saturation using two markedly different decoding algorithms: the steady-state Kalman filter, and a novel technique using Gaussian process regression (GP-DKF).

Restoration of reaching and grasping movements through brain-controlled muscle stimulation in a person with tetraplegia: a proof-of-concept demonstration.

Background: People with chronic tetraplegia, due to high-cervical spinal cord injury, can regain limb movements through coordinated electrical stimulation of peripheral muscles and nerves, known as functional electrical stimulation (FES). Users typically command FES systems through other preserved, but unrelated and limited in number, volitional movements (eg, facial muscle activity, head movements, shoulder shrugs). We report the findings of an individual with traumatic high-cervical spinal cord injury who coordinated reaching and grasping movements using his own paralysed arm and hand, reanimated through implanted FES, and commanded using his own cortical signals through an intracortical brain-computer interface (iBCI).

Signal-independent noise in intracortical brain-computer interfaces causes movement time properties inconsistent with Fitts' law.

Objective: Do movements made with an intracortical BCI (iBCI) have the same movement time properties as able-bodied movements? Able-bodied movement times typically obey Fitts' law: [Formula: see text] (where MT is movement time, D is target distance, R is target radius, and [Formula: see text] are parameters). Fitts' law expresses two properties of natural movement that would be ideal for iBCIs to restore: (1) that movement times are insensitive to the absolute scale of the task (since movement time depends only on the ratio [Formula: see text]) and (2) that movements have a large dynamic range of accuracy (since movement time is logarithmically proportional to [Formula: see text]).

Approach: Two participants in the BrainGate2 pilot clinical trial made cortically controlled cursor movements with a linear velocity decoder and acquired targets by dwelling on them.

Feedback control policies employed by people using intracortical brain-computer interfaces.

Objective: When using an intracortical BCI (iBCI), users modulate their neural population activity to move an effector towards a target, stop accurately, and correct for movement errors. We call the rules that govern this modulation a 'feedback control policy'. A better understanding of these policies may inform the design of higher-performing neural decoders.

Percutaneous transoral clivoplasty and upper cervical vertebroplasties for multifocal skeletal lymphangiomatosis resulting in complete resolution of pain: case report.

Lymphangiomatosis is a rare congenital disorder that results in multiorgan system lymphatic invasion. Symptoms due to axial skeletal involvement can range from chronic bone pain to severe deformity resulting in radiculopathy, myelopathy, and even paralysis. The authors present a case of lymphangiomatosis of the clivus, C-1, and C-2, resulting in chronic pain.

Computational Modeling and Neuroimaging Techniques for Targeting during Deep Brain Stimulation.

Accurate surgical localization of the varied targets for deep brain stimulation (DBS) is a process undergoing constant evolution, with increasingly sophisticated techniques to allow for highly precise targeting. However, despite the fastidious placement of electrodes into specific structures within the brain, there is increasing evidence to suggest that the clinical effects of DBS are likely due to the activation of widespread neuronal networks directly and indirectly influenced by the stimulation of a given target. Selective activation of these complex and inter-connected pathways may further improve the outcomes of currently treated diseases by targeting specific fiber tracts responsible for a particular symptom in a patient-specific manner.

Tailored disconnection based on presurgical evidence in catastrophic epilepsy: report of 2 cases.

Catastrophic epilepsy in infants, often due to extensive cortical dysplasia, has devastating consequences with respect to brain development. Conventional lobar, multilobar, or hemispheric resection in these infants is challenging, carrying an increased operative risk compared with that in older children. Removing a larger tissue volume versus removing or disconnecting the epileptogenic region does not always guarantee better seizure outcome.

Successful Management of Corneal Neuropathic Pain with Intrathecal Targeted Drug Delivery.

Objective: To describe the successful treatment of refractory corneal neuropathic pain with neuromodulation techniques.

Design: Single case report.

Setting: Academic tertiary care center in the United States of America.