Xenotransplantation of porcine progenitor cells in an epileptic California sea lion (Zalophus californianus): illustrative case.

Background: Domoic acid (DA) is a naturally occurring neurotoxin harmful to marine animals and humans. California sea lions exposed to DA in prey during algal blooms along the Pacific coast exhibit significant neurological symptoms, including epilepsy with hippocampal atrophy.

Observations: Here the authors describe a xenotransplantation procedure to deliver interneuron progenitor cells into the damaged hippocampus of an epileptic sea lion with suspected DA toxicosis.

The future perspectives of psychiatric neurosurgery.

The future of psychiatric neurosurgery can be viewed from two separate perspectives: the immediate future and the distant future. Both show promise, but the treatment strategy for mental diseases and the technology utilized during these separate periods will likely differ dramatically. It can be expected that the initial advancements will be built upon progress of neuroimaging and stereotactic targeting while surgical technology becomes adapted to patient-specific symptomatology and structural/functional imaging parameters.

Gamma Knife radiosurgery for obsessive compulsive disorder.

Gamma Knife radiosurgical capsulotomy has been performed for over 40 years as a rarely used surgical intervention for the treatment of obsessive-compulsive disorder. Over time, the procedure has evolved in many ways with most significant modifications being made in target location, number of isocenters and prescribed dose, subsequently producing changes in lesion size and geometry. Long-term clinical response data and adverse outcomes to the earlier empiric treatment parameters have resulted in shifting the target from its initial location within the midpoint of the anterior limb of internal capsule to a currently used point that includes its most ventral portion as well as the ventral striatum.

Artifact Characterization and a Multipurpose Template-Based Offline Removal Solution for a Sensing-Enabled Deep Brain Stimulation Device.

Background: The Medtronic "Percept" is the first FDA-approved deep brain stimulation (DBS) device with sensing capabilities during active stimulation. Its real-world signal-recording properties have yet to be fully described.

Objective: This study details three sources of artifact (and potential mitigations) in local field potential (LFP) signals collected by the Percept and assesses the potential impact of artifact on the future development of adaptive DBS (aDBS) using this device.

Chronic Sensing of Subthalamic Local Field Potentials: Comparison of First and Second Generation Implantable Bidirectional Systems Within a Single Subject.

Background: Many adaptative deep brain stimulation (DBS) paradigms rely upon the ability to sense neural signatures of specific clinical signs or symptoms in order to modulate therapeutic stimulation. In first-generation bidirectional neurostimulators, the ability to sense neural signals during active stimulation was often limited by artifact. Newer devices, with improved design specifications for sensing, have recently been developed and are now clinically available.

Motor Evoked Potential Recordings During Segmented Deep Brain Stimulation-A Feasibility Study.

Background: Segmented deep brain stimulation (DBS) leads, which are capable of steering current in the direction of any 1 of 3 segments, can result in a wider therapeutic window by directing current away from unintended structures, particularly, the corticospinal tract (CST). It is unclear whether the use of motor evoked potentials (MEPs) is feasible during DBS surgery via stimulation of individual contacts/segments in order to quantify CST activation thresholds and optimal contacts/segments intraoperatively.

Objective: To assess the feasibility of using MEP to identify CST thresholds for ring and individual segments of the DBS lead under general anesthesia.

Structural and Functional Imaging in Glioma Management.

The goal of glioma surgery is maximal safe resection in order to provide optimal tumor control and survival benefit to the patient. There are multiple imaging modalities beyond traditional contrast-enhanced magnetic resonance imaging (MRI) that have been incorporated into the preoperative workup of patients presenting with gliomas. The aim of these imaging modalities is to identify cortical and subcortical areas of eloquence, and their relationship to the lesion.

Symptomatic Primary Tethered Optic Chiasm: Technical Case Report.

Background And Importance: Symptomatic tethering of the optic nerves and chiasm is a rare occurrence and has been reported following both surgical and medical treatment of pituitary adenoma. Here we present a case of primary optic chiasm tethering in a patient with empty sella syndrome.

Clinical Presentation: The patient was a 61-yr-old female who presented with progressively worsening bitemporal hemianopsia.

Analysis and Temporal Evolution of Extubation Parameters for Patients Undergoing Single-Stage Circumferential Cervical Spine Surgery.

Objective: Airway obstruction after postoperative extubation is a dreaded but uncommon complication in patients undergoing circumferential cervical spine surgery (CCSS). The cuff leak test (CLT) has been utilized to assess air leak around the endotracheal tube which may reflect airway swelling. In this prospective observational study, we analyze the temporal evolution of CLT and perioperative factors that may influence it.

The Impact of Microelectrode Recording on Lead Location in Deep Brain Stimulation for the Treatment of Movement Disorders.

Objective: During deep brain stimulation (DBS) surgery, microelectrode recording (MER) leads to target refinement from the initial plan in 30% to 47% of hemispheres; however, it is unclear whether the DBS lead ultimately resides within the MER-optimized target in relation to initial radiographic target coordinates in these hemispheres. This study aimed to determine the frequency of discordance between radiographic and neurophysiologic nucleus and whether target optimization with MER leads to a significant change in DBS lead location away from initial target.

Methods: Consecutive cases of DBS surgery with MER using intraoperative computed tomography were included.

Image-Guided Navigation and Robotics in Spine Surgery.

Image guidance (IG) and robotics systems are becoming more widespread in their utilization and can be invaluable intraoperative adjuncts during spine surgery. Both are highly reliant upon stereotaxy and either pre- or intraoperative radiographic imaging. While user-operated IG systems have been commercially available longer and subsequently are more widely utilized across centers, robotics systems provide unique theoretical advantages over freehand and IG techniques for placing instrumentation within the spine.

Abdominal Epilepsy Treated With Vagal Nerve Stimulation: A Case Report.

Background And Importance: Abdominal epilepsy is a rare seizure disorder characterized by episodic gastrointestinal symptoms with electroencephalogram abnormalities. It is typically well treated with anti-epileptic medications; however, little is known about treatment of refractory cases.

Clinical Presentation: The patient is a 16-yr-old male who began experiencing episodic abdominal pain and distension at the age of 2.

Analysis of Movement-Related Beta Oscillations in the Off-Medication State During Subthalamic Nucleus Deep Brain Stimulation Surgery.

Purpose: Local field potential recordings from deep brain stimulation (DBS) leads provide insight into the pathophysiology of Parkinson disease (PD). We recorded local field potential activity from DBS leads within the subthalamic nucleus in patients with PD undergoing DBS surgery to identify reproducible pathophysiological signatures of the disease.

Methods: Local field potentials were recorded in 11 hemispheres from patients with PD undergoing subthalamic nucleus-DBS.

Repair of Temporal Bone Defects via the Middle Cranial Fossa Approach: Treatment of 2 Pathologies With 1 Operation.

Background: Temporal bone dehiscence (TBD) often results in leakage of cerebrospinal fluid (CSF) and/or encephalocele. TBD can also occur over the superior semicircular canal, causing debilitating vertigo. Both can be repaired surgically, but traditional treatment is focused only on one pathology, not both.

Prevalence and Impact of Left-Handedness in Neurosurgery.

Background: Approximately 10%-13% of the population is left-handed (LH), and certain professions have varied representation of LH individuals. LH surgeons must overcome unique difficulties owing to the right-handed (RH) operative environment. This study assesses prevalence and impact of left-handedness on training and operative experience of neurosurgeons.

The Utility of Vancomycin Powder in Reducing Surgical Site Infections in Deep Brain Stimulation Surgery.

Background: The impact of vancomycin powder on reducing postoperative surgical site infections (SSIs) in spine surgery has been studied extensively and is considered standard of care at many institutions. More recently, vancomycin powder has been shown to reduce SSI in cranial neurosurgery; however, limited studies have been performed assessing its impact in reducing SSIs in deep brain stimulation (DBS) surgery.

Objective: To investigate the use of vancomycin powder as an adjunct to the current antibiotic prophylaxis regimen in DBS surgery in a large cohort of patients.

Identification of Stria Medullaris Fibers in the Massa Intermedia Using Diffusion Tensor Imaging.

Background: The massa intermedia (MI) or interthalamic adhesion is an inconsistent band spanning between bilateral medial thalami that is absent in up to 20%-30% of individuals. Little is known of its significance, especially in regard to functional pathways. Probabilistic diffusion tensor imaging (DTI) has recently been used to seed the lateral habenula and define its afferent white matter pathway, the stria medullaris thalami (SM).

Microelectrode accuracy in deep brain stimulation surgery.

Microelectrode recording (MER) provides vital neurophysiological information about target nuclei during deep brain stimulation (DBS). There have been extensive studies looking at the accuracy of DBS lead placement; however, to date, no large series have assessed the accuracy of the microelectrode. In this study, we report the accuracy of microelectrode tip placement in comparison to preoperatively planned radiographic target.

Awake versus Asleep Deep Brain Stimulation Surgery: Technical Considerations and Critical Review of the Literature.

Advancements in neuroimaging have led to a trend toward direct, image-based targeting under general anesthesia without the use of microelectrode recording (MER) or intraoperative test stimulation, also referred to as "asleep" deep brain stimulation (DBS) surgery. Asleep DBS, utilizing imaging in the form of intraoperative computed tomography (iCT) or magnetic resonance imaging (iMRI), has demonstrated reliable targeting accuracy of DBS leads implanted within the globus pallidus and subthalamic nucleus while also improving clinical outcomes in patients with Parkinson's disease. In lieu, of randomized control trials, retrospective comparisons between asleep and awake DBS with MER have shown similar short-term efficacy with the potential for decreased complications in asleep cohorts.

Bilateral Thalamic Edema from Coexisting Choroid Plexus Arteriovenous Malformation and Sinus Thrombosis: Case Report.

Bilateral thalamic dysfunction secondary to venous congestion may result from either venous sinus thrombosis or high flow arteriovenous malformations or a combination of both. We present a case of bilateral thalamic edema resulting from concomitant choroid plexus arteriovenous malformation (AVM) and straight sinus thrombosis and describe our treatment approach. The patient presented with several weeks of progressive confusion and memory deficits.

High-frequency measurement of depressive severity in a patient treated for severe treatment-resistant depression with deep-brain stimulation.

Although there have been previous studies of deep-brain stimulation (DBS), we present, to our knowledge, the first example of high-frequency depressive severity measurement-based DBS treatment in particular and psychiatric treatment in general. Daily post-surgical e-mail prompts for a period of 6 months resulted in 93 administrations of a computerized adaptive test (CAT) of depression severity (CAT-Depression Inventory or CAT-DI) via the internet. There was an average of 3.

Optimization of Microelectrode Recording in Deep Brain Stimulation Surgery Using Intraoperative Computed Tomography.

Background: Microelectrode recording (MER) is used to confirm targeting accuracy during deep brain stimulation (DBS) surgery. We describe a technique using intraoperative computed tomography (CT) extrapolation (iCTE) to predetermine and adjust the trajectory of the guide tube to improve microelectrode targeting accuracy. We hypothesized that this technique would decrease the number of MER tracks and operative time, while increasing the recorded length of the subthalamic nucleus (STN).

Implantation of Responsive Neurostimulation for Epilepsy Using Intraoperative Computed Tomography: Technical Nuances and Accuracy Assessment.

Introduction: Implantation of responsive neurostimulation (RNS) system has been previously discussed in the literature but there is a paucity of data on target accuracy and the use of intraoperative imaging. We describe our experience with 8 patients using intraoperative computed tomography (iCT) during implantation of the NeuroPace RNS system.

Methods: A frame-based system was used.

Improving the accuracy of microelectrode recording in deep brain stimulation surgery with intraoperative CT.

Microelectrode recording (MER) is used to confirm electrophysiological signals within intended anatomic targets during deep brain stimulation (DBS) surgery. We describe a novel technique called intraoperative CT-guided extrapolation (iCTE) to predict the intended microelectrode trajectory and, if necessary, make corrections in real-time before dural opening. Prior to dural opening, a guide tube was inserted through the headstage and rested on dura.