Stereotactic navigation for traumatic parafalcine subdural hematoma evacuation: illustrative cases.

Background: Parafalcine subdural hematomas (pSDHs) are a subtype of subdural hematoma (SDH) that occur most frequently in older patients after blunt trauma. The literature primarily describes two clinical courses for patients with pSDH: those who are neurologically intact with stable examinations and imaging and those with focal deficits, with or without hematoma progression. Surgical management is undoubtedly required for the latter group; however, there are no evidence-based guidelines specifically for pSDH.

A comparative analysis of microsurgical resection versus stereotactic radiosurgery for Spetzler-Martin grade III arteriovenous malformations: A multicenter propensity score matched study.

Background: Spetzler-Martin (SM) Grade III brain arteriovenous malformations (BAVMs) represent a transitional risk zone between low- and high-grade BAVMs, characterized by diverse angioarchitecture. The primary treatment options are endovascular embolization, microsurgical resection (MS), and stereotactic radiosurgery (SRS). This study compares the efficacy and outcomes of MS and SRS.

Stereotactic Radiosurgery in Primary Treatment of Sporadic Small to Medium (<3 cm) Vestibular Schwannomas: A Systematic Review and Meta-Analysis.

Objective: To analyze the literature regarding the use of stereotactic radiosurgery as the primary treatment of vestibular schwannoma to further evaluate efficacy and treatment-related neurologic deficits.

Methods: Online databases were queried to identify relevant studies from January 2001 to December 2020. Full-text articles in English for sporadic vestibular schwannoma treated primarily with radiosurgery and documented hearing preservation data were reviewed.

Comparing stand-alone endovascular embolization versus stereotactic radiosurgery in the treatment of arteriovenous malformations with Spetzler-Martin grades I-III: a propensity score matched study.

Background: Arteriovenous malformations (AVMs) are uncommon cerebral lesions that can cause significant neurological complications. Surgical resection is the gold standard for treatment, but endovascular embolization and stereotactic radiosurgery (SRS) are viable alternatives.

Objective: To compare the outcomes of endovascular embolization versus SRS in the treatment of AVMs with Spetzler-Martin grades I-III.

Parkinsonism originates in a discrete secondary and dystonia in a primary motor cortical-basal ganglia subcircuit.

Although manifesting contrasting phenotypes, Parkinson's disease and dystonia, the two most common movement disorders, can originate from similar pathophysiology. Previously, we demonstrated that lesioning (silencing) of a discrete dorsal region in the globus pallidus (rodent equivalent to globus pallidus externa) in rats and produced parkinsonism, while lesioning a nearby ventral hotspot-induced dystonia. Presently, we injected fluorescent-tagged multi-synaptic tracers into these pallidal hotspots (n = 36 Long Evans rats) and permitted 4 days for the viruses to travel along restricted connecting pathways and reach the motor cortex before sacrificing the animals.

Deep Brain Stimulation of Nucleus Basalis of Meynert improves learning in rat model of dementia.

Background: Deep brain stimulation (DBS) of the nucleus basalis of Meynert (NBM) has been preliminarily investigated as a potential treatment for dementia. The degeneration of NBM cholinergic neurons is a pathological feature of many forms of dementia. Although stimulation of the NBM has been demonstrated to improve learning, the ideal parameters for NBM stimulation have not been elucidated.

Image-Guided Navigation in Spine Surgery: From Historical Developments to Future Perspectives.

Intraoperative navigation is critical during spine surgery to ensure accurate instrumentation placement. From the early era of fluoroscopy to the current advancement in robotics, spinal navigation has continued to evolve. By understanding the variations in system protocols and their respective usage in the operating room, the surgeon can use and maximize the potential of various image guidance options more effectively.

Application of Machine Learning Strategies to Model the Effects of Sevoflurane on Somatosensory-Evoked Potentials during Spine Surgery.

In this study, a small sample of patients' neuromonitoring data was analyzed using machine learning (ML) tools to provide proof of concept for quantifying complex signals. Intraoperative neurophysiological monitoring (IONM) is a valuable asset for monitoring the neurological status of a patient during spine surgery. Notably, this technology, when operated by neurophysiologists and surgeons familiar with proper alarm criteria, is capable of detecting neurological deficits.

Healthy and pathological pallidal regulation of thalamic burst versus tonic mode firing: a computational simulation.

The mechanisms by which the basal ganglia influence the pallidal-receiving thalamus remain to be adequately defined. Our prior in vivo recordings in fully alert normal and dystonic rats revealed that normally fast tonic discharging entopeduncular [EP, rodent equivalent of the globus pallidus internus (GPi)] neurons are pathologically slow, highly irregular, and bursty under dystonic conditions. This, in turn, induces pallidal-receiving thalamic movement-related neurons to change from a healthy burst predominant to a pathological tonic-predominant resting firing mode.

The Use of Intraoperative Neuromonitoring for Cervical Spine Surgery: Indications, Challenges, and Advances.

Intraoperative neuromonitoring (IONM) has become an indispensable surgical adjunct in cervical spine procedures to minimize surgical complications. Understanding the historical development of IONM, indications for use, associated pitfalls, and recent developments will allow the surgeon to better utilize this important technology. While IONM has shown great promise in procedures for cervical deformity, intradural tumors, or myelopathy, routine use in all cervical spine cases with moderate pathology remains controversial.

Transcranial Stimulation for the Treatment of Stimulant Use Disorder.

The increasing prevalence of stimulant use disorder (StUD) involving methamphetamine and cocaine has been a growing healthcare concern in the United States. Cocaine usage is associated with atherosclerosis, systolic and diastolic dysfunction, and arrhythmias. Furthermore, approximately one of every four MIs is cocaine-induced among patients aged 18 to 45.

Nucleus Basalis of Meynert Stimulation for Dementia: Theoretical and Technical Considerations.

Deep brain stimulation (DBS) of nucleus basalis of Meynert (NBM) is currently being evaluated as a potential therapy to improve memory and overall cognitive function in dementia. Although, the animal literature has demonstrated robust improvement in cognitive functions, phase 1 trial results in humans have not been as clear-cut. We hypothesize that this may reflect differences in electrode location within the NBM, type and timing of stimulation, and the lack of a biomarker for determining the stimulation's effectiveness in real time.

Parkinsonism and dystonia are differentially induced by modulation of different territories in the basal ganglia.

Numerous clinical and experimental observations suggest that deficient neuronal signaling in the globus pallidus externa (GPe) is integral to both Parkinson's disease (PD) and dystonia. In our previous studies in jaundiced dystonic rats, widespread silencing of neurons in GP (rodent equivalent to GPe) preceded and persisted during dystonic motor activity. We therefore hypothesized that on a background of slow and highly irregular and bursty neuronal activity in GP, cortical motor drive produces profound inhibition of GP as the basis for action-induced dystonia in Gunn rats.

Preserved dichotomy but highly irregular and burst discharge in the basal ganglia in alert dystonic rats at rest.

Despite its prevalence, the underlying pathophysiology of dystonia remains poorly understood. Using our novel tri-component classification algorithm, extracellular neuronal activity in the globus pallidus (GP), STN, and the entopeduncular nucleus (EP) was characterized in 34 normal and 25 jaundiced dystonic Gunn rats with their heads restrained while at rest. In normal rats, neurons in each nucleus were similarly characterized by two physiologically distinct types: regular tonic with moderate discharge frequencies (mean rates in GP, STN and EP ranging from 35-41 spikes/s) or irregular at slower frequencies (17-20 spikes/s), with a paucity of burst activity.

A novel tri-component scheme for classifying neuronal discharge patterns.

Background: Neuronal discharge patterns can be described by three principle patterns, namely, regular, irregular, and bursty.

New Method: Available discrimination metrics, including global ISI metrics (e.g.