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Synaptic damage is one of the most prevalent pathophysiological responses to traumatic CNS injury and underlies much of the associated cognitive dysfunction; however, it is poorly understood. The D-amino acid, D-serine, serves as the primary co-agonist at synaptic NMDA receptors (NDMARs) and is a critical mediator of NMDAR-dependent transmission and synaptic plasticity. In physiological conditions, D-serine is produced and released by neurons from the enzymatic conversion of L-serine by serine racemase (SRR). However, under inflammatory conditions, glial cells become a major source of D-serine. Here, we report that D-serine synthesized by reactive glia plays a critical role in synaptic damage after traumatic brain injury (TBI) and identify the therapeutic potential of inhibiting glial D-serine release though the transporter Slc1a4 (ASCT1). Furthermore, using cell-specific genetic strategies and pharmacology, we demonstrate that TBI-induced synaptic damage and memory impairment requires D-serine synthesis and release from both reactive astrocytes and microglia. Analysis of the murine cortex and acutely resected human TBI brain also show increased SRR and Slc1a4 levels. Together, these findings support a novel role for glial D-serine in acute pathological dysfunction following brain trauma, whereby these reactive cells provide the excess co-agonist levels necessary to initiate NMDAR-mediated synaptic damage.

Determining the appropriate surgical indications for obtunded octogenarians with traumatic acute subdural hematoma (aSDH) has been challenging. We sought to determine which easily available data would be useful adjuncts to assist in early and quick decision-making.We performed a single-center, retrospective review of patients aged ≥80 years with confirmed traumatic aSDH who had undergone emergent surgery. The clinical measurements included the Karnofsky performance scale score, Charlson comorbidity index, Glasgow coma scale (GCS), and abbreviated injury score. The radiographic measurements included the Rotterdam computed tomography score, aSDH thickness, midline shift, and optic nerve sheath diameter (ONSD). The neurologic outcomes were defined using the extended Glasgow outcome scale-extended (GOS-E) at hospital discharge and 3-month follow-up. The Pearson correlation coefficient was used to compare the ONSD with all clinical, radiographic, and outcome variables. Multivariate logistic regression was used to assess the relationship between the discharge and 3-month GOS-E scores between all clinical and radiographic variables.A total of 17 patients met the inclusion criteria. The mean age was 82.5 ± 1.6 years (range, 80-85 years), and the mean GCS score was 11.2 ± 4.1 (range, 4-15). The mean discharge and 3-month GOS-E scores were 3.4 ± 2.6 (range, 1-8) and 2.3 ± 2.1 (range, 1-7), respectively. We found significant negative correlations between the ONSD and the GCS score (r = -0.62; P0.01) and the ONSD and discharge GOS-E score (r = -0.49; P = 0.05). Multivariate analysis revealed a significant association between the abbreviated injury score and the discharge GOS-E score (P = 0.05).Octogenarians sustaining aSDH and requiring emergent surgery have poor outcomes. More data are needed to determine whether the ONSD can be a useful adjunct tool to predict the efficacy of emergent surgery.

Background The response to the global severe acute respiratory syndrome coronavirus 2 pandemic culminated in mandatory isolation throughout the world, with nationwide confinement orders issued to decrease viral spread. These drastic measures were successful in “flattening the curve” and maintaining the previous rate of coronavirus disease 2019 infections and deaths. To date, the effects of the coronavirus disease 2019 pandemic on neurotrauma has not been reported. Methods We retrospectively analyzed hospital admissions from Ryder Trauma Center at Jackson Memorial Hospital, during the months of March and April from 2016 to 2020. Specifically, we identified all patients who had cranial neurotrauma consisting of traumatic brain injury and/or skull fractures, as well as spinal neurotrauma consisting of vertebral fractures and/or spinal cord injury. We then performed chart review to determine mechanism of injury and if emergent surgical intervention was required. Results Compared with previous years, we saw a significant decline in the number of neurotraumas during the pandemic, with a 62% decline after the lockdown began. The number of emergent neurotrauma surgical cases also significantly decreased by 84% in the month of April. Interestingly, although the number of vehicular traumas decreased by 77%, there was a significant 100% increase in the number of gunshot wounds. Conclusions Population seclusion had a direct effect on the frequency of neurotrauma, whereas the change in relative proportion of certain mechanisms may be associated with the psychosocial effects of social distancing and quarantine.

Background Deep brain stimulation (DBS) is considered standard of care for the treatment of medically refractory Parkinson disease (PD). The placement of brain electrodes is performed using contrast imaging to enhance blood vessel identification during stereotactic planning. We present our experience with a series of patients implanted using noncontrast imaging. Methods All cases of DBS surgery for PD performed between 2012 and 2018 with noncontrast imaging were retrospectively reviewed. Clinical features, postoperative imaging, and complications were analyzed. Results A total of 287 deep-seated electrodes were implanted in 152 patients. Leads were placed at the subthalamic nucleus and globus pallidus internus in 258 and 29 hemispheres, respectively. We identified 2 cases of intracranial hemorrhage (0.7%). Conclusions DBS lead placement can be performed without the use of intravenous contrast with a postoperative intracranial hemorrhage rate comparable with other reported series.

Postsurgical seizure outcome following laser interstitial thermal therapy (LiTT) for the management of drug-resistant mesial temporal lobe epilepsy (MTLE) has been limited to 2 years. Furthermore, its impact on presurgical mood and anxiety disorders has not been investigated. The objectives of this study were (1) to identify seizure outcome changes over a period ranging from 18 to 81 months; (2) to investigate the seizure-free rate in the last follow-up year; (3) to identify the variables associated with seizure freedom; and (4) to identify the impact of LiTT on presurgical mood and anxiety disorders.Medical records of all patients who underwent LiTT for MTLE from 2013 to 2019 at the University of Miami Comprehensive Epilepsy Center were retrospectively reviewed. Demographic, epilepsy-related, cognitive, psychiatric, and LiTT-related data were compared between seizure-free (Engel Class I) and non-seizure-free (Engel Class II + III + IV) patients. Statistical analyses included univariate and multivariate stepwise logistic regression analyses.Forty-eight patients (mean age = 43 ± 14.2 years, range = 21-78) were followed for a mean period of 50 ± 20.7 months (range = 18-81); 29 (60.4%) achieved an Engel Class I outcome, whereas 11 (22.9%) had one to three seizures/year. Seizure-freedom rate decreased from 77.8% to 50% among patients with 24- and61-month follow-up periods, respectively. In the last follow-up year, 83% of all patients were seizure-free. Seizure freedom was associated with having mesial temporal sclerosis (MTS), no presurgical focal to bilateral tonic-clonic seizures, and no psychopathology in the last follow-up year. Presurgical mood and/or anxiety disorder were identified in 30 patients (62.5%) and remitted after LiTT in 19 (62%).LiTT appears to be a safe and effective surgical option for treatment-resistant MTLE, particularly among patients with MTS. Remission of presurgical mood and anxiety disorders can also result from LiTT.

OBJECTIVE Motor vehicle collisions (MVCs) account for 1.35 million deaths and cost $518 billion US dollars each year worldwide, disproportionately affecting young patients and low-income nations. The ability to successfully anticipate clinical outcomes will help physicians form effective management strategies and counsel families with greater accuracy. The authors aimed to train several classifiers, including a neural network model, to accurately predict MVC outcomes. METHODS A prospectively maintained database at a single institution’s level I trauma center was queried to identify all patients involved in MVCs over a 20-year period, generating a final study sample of 16,287 patients from 1998 to 2017. Patients were categorized by in-hospital mortality (during admission) and length of stay (LOS), if admitted. All models included age (years), Glasgow Coma Scale (GCS) score, and Injury Severity Score (ISS). The in-hospital mortality and hospital LOS models further included time to admission. RESULTS After comparing a variety of machine learning classifiers, a neural network most effectively predicted the target features. In isolated testing phases, the neural network models returned reliable, highly accurate predictions: the in-hospital mortality model performed with 92% sensitivity, 90% specificity, and a 0.98 area under the receiver operating characteristic curve (AUROC), and the LOS model performed with 2.23 days mean absolute error after optimization. CONCLUSIONS The neural network models in this study predicted mortality and hospital LOS with high accuracy from the relatively few clinical variables available in real time. Multicenter prospective validation is ultimately required to assess the generalizability of these findings. These next steps are currently in preparation.

Neuromodulation techniques for pain treatment have been used since ancient Rome, but knowledge about the interaction of electricity and drugs with the central nervous system (electrical and chemical neuromodulation) was not clear until the middle of the twentieth century. It was only then that the advent of neuromodulatory techniques allowed for more widespread clinical application for the treatment of several neurological and psychiatric conditions, including pain. In this chapter, we present the history of neuromodulation techniques for the treatment of pain, from its first applications to a more organized approach encompassing physiological and technological improvements producing the current concepts in neuromodulation. We also take an in-depth look at the current surgical techniques for neuromodulatory improvement of pain.

Over 15 million epilepsy patients worldwide have drug-resistant epilepsy. Successful surgery is a standard of care treatment but can only be achieved through complete resection or disconnection of the epileptogenic zone, the brain region(s) where seizures originate. Surgical success rates vary between 20% and 80%, because no clinically validated biological markers of the epileptogenic zone exist. Localizing the epileptogenic zone is a costly and time-consuming process, which often requires days to weeks of intracranial EEG (iEEG) monitoring. Clinicians visually inspect iEEG data to identify abnormal activity on individual channels occurring immediately before seizures or spikes that occur interictally (i.e. between seizures). In the end, the clinical standard mainly relies on a small proportion of the iEEG data captured to assist in epileptogenic zone localization (minutes of seizure data versus days of recordings), missing opportunities to leverage these largely ignored interictal data to better diagnose and treat patients. IEEG offers a unique opportunity to observe epileptic cortical network dynamics but waiting for seizures increases patient risks associated with invasive monitoring. In this study, we aimed to leverage interictal iEEG data by developing a new network-based interictal iEEG marker of the epileptogenic zone. We hypothesized that when a patient is not clinically seizing, it is because the epileptogenic zone is inhibited by other regions. We developed an algorithm that identifies two groups of nodes from the interictal iEEG network: those that are continuously inhibiting a set of neighbouring nodes (‘sources’) and the inhibited nodes themselves (‘sinks’). Specifically, patient-specific dynamical network models were estimated from minutes of iEEG and their connectivity properties revealed top sources and sinks in the network, with each node being quantified by source-sink metrics. We validated the algorithm in a retrospective analysis of 65 patients. The source-sink metrics identified epileptogenic regions with 73% accuracy and clinicians agreed with the algorithm in 93% of seizure-free patients. The algorithm was further validated by using the metrics of the annotated epileptogenic zone to predict surgical outcomes. The source-sink metrics predicted outcomes with an accuracy of 79% compared to an accuracy of 43% for clinicians’ predictions (surgical success rate of this dataset). In failed outcomes, we identified brain regions with high metrics that were untreated. When compared with high frequency oscillations, the most commonly proposed interictal iEEG feature for epileptogenic zone localization, source-sink metrics outperformed in predictive power (by a factor of 1.2), suggesting they may be an interictal iEEG fingerprint of the epileptogenic zone.

In this review, we provide an overview of the current research and treatment of all types of traumatic brain injury (TBI) before illustrating the need for improved care specific to mild TBI patients. Contemporary issues pertaining to acute care of mild TBI including prognostication, neurosurgical intervention, repeat radiographic imaging, reversal of antiplatelet and anticoagulation medications, and cost savings initiatives are reviewed. Lastly, the effect of COVID-19 on TBI is addressed.

Loss of hand function after cervical spinal cord injury severely impairs functional independence. We describe a method for restoring volitional control of hand grasp in one 21-year-old male subject with complete cervical quadriplegia (C5 American Spinal Injury Association Impairment Scale A) using a portable fully implanted brain–computer interface within the home environment. The brain–computer interface consists of subdural surface electrodes placed over the dominant-hand motor cortex and connects to a transmitter implanted subcutaneously below the clavicle, which allows continuous reading of the electrocorticographic activity. Movement-intent was used to trigger functional electrical stimulation of the dominant hand during an initial 29-weeks laboratory study and subsequently via a mechanical hand orthosis during in-home use. Movement-intent information could be decoded consistently throughout the 29-weeks in-laboratory study with a mean accuracy of 89.0% (range 78–93.3%). Improvements were observed in both the speed and accuracy of various upper extremity tasks, including lifting small objects and transferring objects to specific targets. At-home decoding accuracy during open-loop trials reached an accuracy of 91.3% (range 80–98.95%) and an accuracy of 88.3% (range 77.6–95.5%) during closed-loop trials. Importantly, the temporal stability of both the functional outcomes and decoder metrics were not explored in this study. A fully implanted brain–computer interface can be safely used to reliably decode movement-intent from motor cortex, allowing for accurate volitional control of hand grasp., Brain–computer interfaces, which translate internal electrical signals related to desired hand movement may be used to restore independence to patients with paralysis. In this work, Cajigas et al. demonstrate that a fully implanted interface can reliably decode motor commands using electrocorticography and can be deployed for home use. Such systems may provide means for self-driven portable rehabilitation and assistance., Graphical Abstract Graphical Abstract

BACKGROUND Primary decompressive craniectomy (DC) is commonly performed for patients with traumatic brain injury (TBI). Some, but not all patients, will benefit from invasive monitoring of intracranial pressure (ICP) after surgery. We intended to identify risk factors for elevated ICP after primary DC to treat TBI. METHODS A retrospective chart review study identified all patients at our institution who underwent primary DC for TBI during the study period and who had ICP monitors placed at the time of surgery. Various preoperative and intraoperative variables were assessed for correlation with the presence of postoperative elevated ICP. RESULTS Postoperative elevated ICP occurred in 36% of patients after DC. In univariate analysis, Glasgow Coma Scale

Epilepsy is a global epidemic and 30% of the 60 million patients do not respond to medication treatment. The only treatment options for patients with medically refractory epilepsy are surgical removal or electrical stimulation of the epileptogenic zone (EZ) i.e. the source of their seizures. Despite extensive evaluations with neuroimaging, visual EEG analysis and clinical testing, surgical success rates vary between 30-70%. Currently, no computational methods have been translated into the clinic to assist in localizing the EZ. Here, we applied a dynamical network model that quantifies the fragility of nodes within a patient9s intracranial EEG (iEEG) brain network. Fragility is quantified as the minimal amount of perturbation that must to be applied to a node9s influence on a "balanced" network to cause imbalance. Here, a balanced network is one in which the connectivity between excitatory and inhibitory nodes render a stable system, and an imbalanced network is unstable and hence can generate seizures. Using iEEG data from 91 patients treated across 5 epilepsy centers (44 successes, 47 failures), we demonstrated that nodal fragility is greater in electrodes within the EZ. In addition, we compared fragility of iEEG nodes to 7 frequency-based and 14 graph theoretic features of the EZ in both seizure (n=91) and non-seizure data (n=54). We calculated a confidence statistic, defined as the ratio of the value of a given feature averaged across electrodes in the clinically annotated seizure onset zone to its average across all other electrodes. Fragility has a significantly greater effect size difference between surgical outcomes when compared to other features. This novel feature, outperformed the most popular iEEG features when comparing across surgical outcomes, possibly defining a superior network-based EEG fingerprint for the EZ.

ObjectiveTo provide a review of cognitive outcomes across a full neuropsychological profile in patients who underwent laser interstitial thermal therapy (LiTT) for mesiotemporal epilepsy (mTLE).MethodsWe examined cognitive outcomes following LiTT for mTLE by reviewing a consecutive series of 26 patients who underwent dominant or nondominant hemisphere procedures. Each patient's pre- and postsurgical performance was examined for clinically significant change (>1SD improvement or decline on standardized scores), with a neuropsychologic battery that included measures of language, memory, executive functioning, and processing speed.ResultsPresurgical performance was largely consistent with previous research, where patients suffering from dominant hemisphere epilepsies demonstrated deficits in verbal learning and memory, whereas patients with nondominant hemisphere scored lower on visually mediated tests. Case-by-case review comparing presurgical to postsurgical scores revealed clinically significant improvement in both dominant and nondominant patients in learning and memory and other aspects of cognition such as processing speed and executive functioning. Of the few patients who did experience clinically significant decline following LiTT, a greater proportion had undergone dominant hemisphere procedures.ConclusionsCompared with the outcome literature of dominant open anterior temporal lobectomies (ATLs), where postsurgical decline has been documented in up to 40%–60% of cases, our LiTT case series exhibited a much lower incidence of postoperative language or verbal memory decline. Moreover, promising rates of postoperative improvements were also observed across multiple cognitive domains. Future studies exploring cognitive outcomes following LiTT should include comprehensive neuropsychological findings, rather than only select domains, as clinically significant change can occur in areas other than those typically associated with mesiotemporal structures.

Laser interstitial thermal therapy (LITT) is a novel MR thermometry-guided thermoablative tool revolutionizing the clinical management of brain tumors. A limitation of LITT is our inability to estimate a priori how tissues will respond to thermal energy, which hinders treatment planning and delivery. The aim of this study was to determine whether brain tumor LITT ablation dynamics may be predicted by features of the preoperative MRI and the relevance of these data, if any, to the recurrence of metastases after LITT. Intraoperative thermal damage estimate (TDE) map pixels representative of irreversible damage were retrospectively quantified relative to ablation onset for 101 LITT procedures. Raw TDE pixel counts and TDE pixel counts modelled with first order dynamics were related to eleven independent variables derived from the preoperative MRI, demographics, laser settings, and tumor pathology. Stepwise regression analysis generated predictive models of LITT dynamics, and leave-one-out cross validation evaluated the accuracy of these models at predicting TDE pixel counts solely from the independent variables. Using a deformable atlas, TDE maps were co-registered to the immediate post-ablation MRI, allowing comparison of predicted and actual ablation sizes. Brain tumor TDE pixel counts modelled with first order dynamics, but not raw pixel counts, are correlated with the independent variables. Independent variables showing strong relations to the TDE pixel measures include T1 gadolinium and T2 signal, perfusion, and laser power. Associations with tissue histopathology are minimal. Leave-one-out analysis demonstrates that predictive models using these independent variables account for 77% of the variance observed in TDE pixel counts. Analysis of metastases treated revealed a trend towards the over-estimation of LITT effects by TDE maps during rapid ablations, which was associated with tumor recurrence. Features of the preoperative MRI are predictive of LITT ablation dynamics and could eventually be used to improve the clinical efficacy with which LITT is delivered to brain tumors.

Introduction Anxiety and depression are common in PD, occurring in an estimated 30%–40% of PD patients. However, the extent to which these emotional symptoms interfere with Deep Brain Stimulation (DBS) outcomes is not well established. This study examined the association between pre-operative emotional well-being and postsurgical cognitive, emotional, and motor performance in PD. Methods Forty-nine PD patients underwent neurological, neuropsychological (global cognition, processing speed, language, visuospatial, memory), and emotional assessments pre- and post-DBS. Fifteen patients were administered the UPDRS. Patients were divided into Anxious (Anx; n = 21), Comorbid Anxious and Depressed (Anx + Dep; n = 15), and Emotionally Asymptomatic (EA; n = 13) based on BAI and BDI-II cutoffs, and compared on pre-post changes in neurocognitive, mood, and motor scores using analyses of covariance (ANCOVA), controlling for education, ethnicity, and disease duration. Results Pre-DBS, there were no significant differences between the three groups on any neuropsychological measure. Overall change from pre-to post-DBS revealed declines on multiple cognitive measures and lower symptom endorsement on the BAI among all participants. No group differences were observed on neurocognitive measures, mood, or UPDRS. Conclusions PD patients with mild-moderate anxiety or comorbid anxiety/depression pre-DBS do not show greater cognitive, emotional, and motor changes post-DBS compared to emotionally asymptomatic patients. These data emphasize the importance of discussing potential DBS outcomes, while keeping in mind that psychiatric comorbidity should not necessarily exclude patients from DBS. The notion that premorbid mood symptoms could disqualify a candidate for surgery would be a disservice, as this group performs comparably to asymptomatic peers.

Background: Laser interstitial thermal therapy (LITT) has recently gained popularity as a minimally invasive surgical option for the treatment of mesiotemporal epilepsy (mTLE). Similar to traditional open procedures for epilepsy, the most frequent neurological complications of LITT are visual deficits; however, a critical analysis of these injuries is lacking. Objectives: To evaluate the visual deficits that occur after LITT for mTLE and their etiology. Method: We surveyed five academic epilepsy centers that regularly perform LITT for cases of self-reported postoperative visual deficits. For these patients all pre-, intra- and postoperative MRIs were co-registered with an anatomic atlas derived from 7T MRI data. This was used to estimate thermal injury to early visual pathways and measure imaging variables relevant to the LITT procedure. Using logistic regression, we then compared 14 variables derived from demographics, mesiotemporal anatomy, and the surgical procedure for the patients with visual deficits to a normal cohort comprised of the first 30 patients to undergo this procedure at a single institution. Results: Of 90 patients that underwent LITT for mTLE, 6 (6.7%) reported a postoperative visual deficit. These included 2 homonymous hemianopsias (HHs), 2 quadrantanopsias, and 2 cranial nerve (CN) IV palsies. These deficits localized to the posterior aspect of the ablation, corresponding to the hippocampal body and tail, and tended to have greater laser energy delivered in that region than the normal cohort. The patients with HH had insult localized to the lateral geniculate nucleus, which was ­associated with young age and low choroidal fissure CSF volume. Quadrantanopsia, likely from injury to the optic radiation in Meyer’s loop, was correlated with a lateral trajectory and excessive energy delivered at the tail end of the ablation. Patients with CN IV injury had extension of contrast to the tentorial edge associated with a mesial laser trajectory. Conclusions: LITT for epilepsy may be complicated by various classes of visual deficit, each with distinct etiology and clinical significance. It is our hope that by better understanding these injuries and their mechanisms we can eventually reduce their occurrence by identifying at-risk patients and trajectories and appropriately tailoring the ablation procedure.

Background Current guidelines prescribe emergent decompression of acute subdural hematomas (aSDHs) with width 10 mm or larger or midline shift 5 mm or larger. A subset of patients who meet these criteria, including those with high Glasgow Coma Scale (GCS) scores and coagulopathy because of medication or multiple medical comorbidities, may be treated conservatively until the hematoma can be removed by burr hole drainage. We present a series of conservatively managed surgical patients with aSDH, examining their hospital course and outcomes. Methods Patients were included who met guidelines for surgery on admission but who had decompression delayed until it could be accomplished by burr hole drainage. Charts were reviewed for presentation, computed tomography scan findings, and outcomes. Patients were classified according to outcome and whether their eventual surgery was scheduled or emergent. Results Eighteen patients were included with a mean age of 70.2 years. Average GCS score at presentation was 14.6 ± 0.6. Most patients were using some form of blood-thinning medication at presentation (72.2%). Admission CT scan revealed aSDH with a mean width of 13.6 mm and midline shift of 6.6 mm. Average total length of stay was 28.4 ± 17.0 days, of which 14.2 ± 9.2 days were spent in the intensive care unit. Outcomes were generally acceptable, with an average Glasgow Outcome Scale score at discharge of 3.8 ± 1.4. There were only 2 deaths, neither of which was related to the initial trauma or a neurologic process. Conclusions Delayed treatment of aSDH by burr hole drainage is an effective option in certain patients who are suboptimal craniotomy candidates. Acceptable outcomes may be achievable with this conservative approach, when applied in appropriate patients.

Background Hypothermia is neuroprotective in some ischemia–reperfusion injuries. Ischemia–reperfusion injury may occur with traumatic subdural hematoma (SDH). This study aimed to determine whether early induction and maintenance of hypothermia in patients with acute SDH would lead to decreased ischemia–reperfusion injury and improve global neurologic outcome. Methods This international, multicenter randomized controlled trial enrolled adult patients with SDH requiring evacuation of hematoma within 6 h of injury. The intervention was controlled temperature management of hypothermia to 35 °C prior to dura opening followed by 33 °C for 48 h compared with normothermia (37 °C). Investigators randomly assigned patients at a 1:1 ratio between hypothermia and normothermia. Blinded evaluators assessed outcome using a 6-month Glasgow Outcome Scale Extended score. Investigators measured circulating glial fibrillary acidic protein and ubiquitin C-terminal hydrolase L1 levels. Results Independent statisticians performed an interim analysis of 31 patients to assess the predictive probability of success and the Data and Safety Monitoring Board recommended the early termination of the study because of futility. Thirty-two patients, 16 per arm, were analyzed. Favorable 6-month Glasgow Outcome Scale Extended outcomes were not statistically significantly different between hypothermia vs. normothermia groups (6 of 16, 38% vs. 4 of 16, 25%; odds ratio 1.8 [95% confidence interval 0.39 to ∞], p = .35). Plasma levels of glial fibrillary acidic protein (p = .036), but not ubiquitin C-terminal hydrolase L1 (p = .26), were lower in the patients with favorable outcome compared with those with unfavorable outcome, but differences were not identified by temperature group. Adverse events were similar between groups. Conclusions This trial of hypothermia after acute SDH evacuation was terminated because of a low predictive probability of meeting the study objectives. There was no statistically significant difference in functional outcome identified between temperature groups.

Background Anxiety and sleep disturbances are prevalent in Parkinson's disease (PD). Benzodiazepines (BZDs) are commonly used to treat these symptoms; however, they are associated with unfavorable side effects such as falls and cognitive slowing in the general non-PD population. Examining the effects of BZDs in PD is imperative as these medications could pose an increased risk to PD patients who are already vulnerable to falls and cognitive deficits. Methods Eighty-four patients diagnosed with idiopathic PD, of which 60% were Hispanic, underwent clinical evaluations including the Unified Parkinson's Disease Rating Scale (UPDRS) and comprehensive neuropsychological testing examining global cognition, language, visuospatial skills, memory, executive function, mood, and sleep quality. Thirty-six patients taking BZDs (BZD+) were compared to forty-eight patients not using any BZDs (BZD-) employing appropriate statistical tests depending on the measures' characteristics. Results BZD+ PD patients performed below the BZD- group on short-term memory but not on delayed recall, and performed better on a measure of visuospatial judgment. The BZD+ group endorsed more symptoms of anxiety and depression as well as poorer sleep quality. No significant differences were noted on other measures of cognition or motor function. Conclusion PD patients taking BZDs may experience select changes in cognition and mood. These changes are isolated and mild, and suggest that for some patients, BZDs may be a viable pharmacologic intervention that does not alter cognitive and motor function compared to those not taking these medications.

Loss of hand function after cervical spinal cord injury severely impairs functional independence. We describe a method for restoring volitional control of hand grasp in a subject with complete cervical quadriplegia (C5 ASIA Impairment Scale A) using a portable fully implanted brain-computer interface (BCI) within the home environment. The BCI consists of subdural surface electrodes placed over the dominant-hand motor cortex and connects to a transmitter implanted subcutaneously below the clavicle, which allows continuous reading of the electrocorticographic (ECoG) activity. Movement-intent was used to trigger functional electrical stimulation (FES) of the dominant hand during an initial 29-week laboratory study and subsequently via a mechanical hand orthosis during in-home use. Movement intent information could be decoded consistently throughout the 29-week in-laboratory study with a mean accuracy of 89.0% (range 78-93.3%). Improvements were observed in both the speed and accuracy of various upper extremity tasks, including lifting small objects and transferring objects to specific targets. After study week 23, the subject began to be able to extend his right thumb volitionally in the absence of the FES orthosis. At home decoding accuracy during open-loop trials reached an accuracy of 91.3% (range 80-98.95%) and an accuracy of 88.3% (range 77.6-95.5%) during closed-loop trials. A fully implanted BCI can be safely used to reliably decode movement intent from motor cortex, allowing for accurate volitional control of hand grasp and may potentially re-engage latent neural pathways to allow targeted re-innervation of muscles below the level of injury. (Funded by the Miami Project to Cure Paralysis; ClinicalTrials.gov number, NCT02564419.)

Background Freezing of gait (FOG) is a particularly debilitating motor deficit seen in a subset of Parkinson’s disease (PD) patients that is poorly responsive to standard levodopa therapy or deep brain stimulation (DBS) of established PD targets such as the subthalamic nucleus and the globus pallidus interna. The proposal of a DBS target in the midbrain, known as the pedunculopontine nucleus (PPN) to address FOG, was based on its observed pathology in PD and its hypothesized involvement in locomotor control as a part of the mesencephalic locomotor region, a functionally defined area of the midbrain that elicits locomotion in both intact animals and decerebrate animal preparations with electrical stimulation. Initial reports of PPN DBS were met with much enthusiasm; however, subsequent studies produced mixed results, and recent meta-analysis results have been far less convincing than initially expected. A closer review of the extensive mesencephalic locomotor region (MLR) preclinical literature, including recent optogenetics studies, strongly suggests that the closely related cuneiform nucleus (CnF), just dorsal to the PPN, may be a superior target to promote gait initiation. Methods We will conduct a prospective, open-label, single-arm pilot study to assess safety and feasibility of CnF DBS in PD patients with levodopa-refractory FOG. Four patients will receive CnF DBS and have gait assessments with and without DBS during a 6-month follow-up. Discussion This paper presents the study design and rationale for a pilot study investigating a novel DBS target for gait dysfunction, including targeting considerations. This pilot study is intended to support future larger scale clinical trials investigating this target. Trial registration ClinicalTrials.gov identifier: NCT04218526 (registered January 6, 2020)

Objective. Automatic detection of interictal epileptiform discharges (IEDs, short as ‘spikes’) from an epileptic brain can help predict seizure recurrence and support the diagnosis of epilepsy. Developing fast, reliable and robust detection methods for IEDs based on scalp or intracranial electroencephalogram (iEEG) may facilitate online seizure monitoring and closed-loop neurostimulation. Approach. We developed a new deep learning approach, which employs a long short-term memory network architecture (‘IEDnet’) and an auxiliary classifier generative adversarial network (AC-GAN), to train on both expert-annotated and augmented spike events from iEEG recordings of epilepsy patients. We validated our IEDnet with two real-world iEEG datasets, and compared IEDnet with the support vector machine (SVM) and random forest (RF) classifiers on their detection performances. Main results. IEDnet achieved excellent cross-validated detection performances in terms of both sensitivity and specificity, and outperformed SVM and RF. Synthetic spike samples augmented by AC-GAN further improved the detection performance. In addition, the performance of IEDnet was robust with respect to the sampling frequency and noise. Furthermore, we demonstrated the cross-institutional generalization ability of IEDnet while testing between two datasets. Significance. IEDnet achieves excellent detection performances in identifying interictal spikes. AC-GAN can produce augmented iEEG samples to improve supervised deep learning.

INTRODUCTION Long regarded as "America's Past Time", over 8.6 million children partake in organized and recreational baseball. Although improved equipment has reduced contemporary injury rates, nearly half of pediatric baseball injuries requiring hospitalization are due to craniofacial trauma. Sideline personnel at the youth levels, often without advanced medical training, frequently act as first-responders in instances of acute craniofacial injury. METHODS An IRB-approved survey was distributed nationally to target field personnel working at youth, high school, collegiate, and professional baseball levels. Survey items included: comfort in assessing subtypes of acute craniofacial trauma (loss of consciousness (LOC), skull injury, orbital injury, nasal injury, and dental injury) via Likert scale, years of medical training, presence of an emergency action plan (EAP), and access to higher level care from emergency medical services (EMS) or a nearby hospital. RESULTS When comparing the amateur and professional cohorts, the respondents from professional teams were significantly more confident in assessing LOC (P = 0.001), skull injury (P

Background: Freezing of gait (FOG) is a particularly debilitating motor deficit seen in a subset of Parkinson’s Disease (PD) patients that is poorly responsive to standard levodopa therapy or deep brain stimulation (DBS) of established PD targets such as the subthalamic nucleus and the globus pallidus interna. The proposal of a DBS target in the midbrain, known as the pedunculopontine nucleus (PPN) to address FOG was based on its observed pathology in PD and its hypothesized involvement in locomotor control as a part of the mesencephalic locomotor region, a functionally defined area of the midbrain that elicits locomotion in both intact animals and decerebrate animal preparations with electrical stimulation. Initial reports of PPN DBS were met with much enthusiasm; however, subsequent studies produced mixed results, and recent meta-analysis results have been far less convincing than initially expected. A closer review of the extensive MLR preclinical literature, including recent optogenetics studies, strongly suggests that the closely related cuneiform nucleus (CnF), just dorsal to the PPN, may be a superior target to promote gait initiation.Methods: We will conduct a prospective, open-label, single-arm pilot study to assess safety and feasibility of CnF DBS in PD patients with levodopa-refractory FOG. Four patients will receive CnF DBS and have gait assessments with and without DBS during a 6-month follow up.Discussion: This paper presents the study design and rationale for a pilot study investigating a novel DBS target for gait dysfunction, including targeting considerations. This pilot study is intended to support future larger scale clinical trials investigating this target.Trial Registration: Clinicaltrials.gov Identifier: NCT04218526 (registered January 6, 2020), https://www.clinicaltrials.gov/ct2/show/NCT04218526

Patients who present with traumatic brain injury (TBI) combined with blunt cerebrovascular injuries (BCVI) are difficult to manage, in part because treatment for each entity may exacerbate the other. It is necessary to develop a treatment paradigm that ensures maximum benefit while mitigating the opposing risks. A cohort of 150 patients from 2015 to present, with either internal carotid artery (ICA) and/or vertebral artery (VA) dissections or pseudoaneurysms, was cross-referenced with those who had sustained TBI. Of the 38 patients identified with both TBI and BCVI, 25 suffered ICA injuries, 10 had VA injuries and 3 had combined ICA/VA injuries. Unilateral BCVI occurred in 30 patients, while 8 had bilateral BCVI. Two patients required surgical intervention for TBI, and 5 patients required endovascular intervention for BCVI. Positive emboli detection studies (EDS) on transcranial dopplers (TCD) were demonstrated in 19 patients, with 9 patients having radiographic evidence of stroke. Anti-platelet therapy was initiated in 32 patients, and anti-coagulation in 10 patients, without new or worsening intracranial hemorrhages (ICH). Overall, 76% of patients were able to be discharged home or to rehabilitation, with good recovery demonstrated in 73% of the patients who had appropriate follow-up. In the setting of concurrent TBI and BCVI, use of anti-platelet/coagulation to prevent stroke can be safe if monitored closely. Here we describe a treatment paradigm which weighs the risk and benefits of therapies based on severity of ICH and stroke prevention, which tended to result in good disposition and recovery.

Background Deep brain stimulation of the ventral intermediate nucleus (VIM) or caudal zona incerta (cZI) is effective for refractory essential tremor (ET). To refine stereotactic planning for lead placement, we developed a unique individualized anatomy-based planning protocol that targets both the VIM and the cZI in patients with ET. Methods 33 patients with ET underwent VIM-cZI lead implantation with targeting based on our protocol. Indirect targeting was adjusted based on anatomic landmarks as reference lines bisecting the red nuclei and ipsilateral subthalamus. Outcomes were evaluated through the follow-up of 31.1 ± 18.4 months. Active contact coordinates were obtained from reconstructed electrodes in the Montreal Neurological Institute space using the MATLAB Lead-DBS toolbox. Results Mean tremor improvement was 79.7% ± 22.4% and remained stable throughout the follow-up period. Active contacts at last postoperative visit had mean Montreal Neurological Institute coordinates of 15.5 ± 1.6 mm lateral to the intercommissural line, 15.3 ± 1.8 mm posterior to the anterior commissure, and 1.4 ± 2.9 mm below the intercommissural plane. No hemorrhagic complications were observed in the analyzed group. Conclusions Individualized anatomy-based VIM-cZI targeting is feasible and safe and is associated with favorable tremor outcomes.

After traumatic brain injury, decompressive craniectomy (DC) is a second-tier, late therapy for refractory intracranial hypertension. We hypothesize that early DC, based on CT evidence of intracranial hypertension, improves intracranial pressure (ICP) and cerebral perfusion pressure (CPP). From September 2008 to January 2015, 286 traumatic brain injury patients requiring invasive ICP monitoring at a single Level I trauma center were reviewed. DC and non-DC patients were propensity score matched 1:1, based on demographics, hemodynamics, injury severity score (ISS), Glasgow Coma Scale (GCS), transfusion requirements, and need for vasopressor therapy. Data are presented as M ± SD or median (IQR) and compared at P ≤ 0.05. The study population was 42 ± 17 years, 84 per cent male, ISS = 29 ± 11, GCS = 6 (5), length of stay (LOS) = 32(40) days, and 28 per cent mortality. There were 116/286 (41%) DC, of which 105/116 (91%) were performed at the time of ICP placement. For 50 DC propensity matched to 50 non-DC patients, the midline shift was 7(11) versus 0(5) mm ( P < 0.001), abnormal ICP (hours > 20 mm Hg) was 1(10) versus 8(16) ( P = 0.017), abnormal CPP (hours < 60 mm Hg) was 0(6) versus 4(9) ( P = 0.008), daily minimum CPP (mm Hg) was 67(13) versus 62(17) ( P = 0.010), and daily maximum ICP (mm Hg) was 18(9) versus 22(11) ( P < 0.001). However, LOS [33(37) versus 25(34) days], mortality (24 versus 30%), and Glasgow Outcome Score Extended [3.0(3.0) versus 3.0(4.0)] did not improve significantly. Early DC for CT evidence of intracranial hypertension decreased abnormal ICP and CPP time and improved ICP and CPP thresholds, but had no obvious effect on the outcome.

Background Laser interstitial thermal therapy (LITT) is quickly emerging as an effective surgical therapy for temporal lobe epilepsy (TLE). One of the most frequent complications of the procedure is postoperative visual field cuts, but the physiopathology of these deficits is unknown. Objective To evaluate potential causes of visual deficits after LITT for TLE in an attempt to minimize this complication. Methods This retrospective chart review compares the case of a 24-year-old male who developed homonymous hemianopsia following LITT for TLE to 17 prior patients who underwent the procedure and suffered no visual deficit. We examined both features of the surgical approach (trajectory, laser energy, ablation size) and of preoperative surgical anatomy, derived from volumetric tracings of mesiotemporal structures. Results For the patient with postoperative homonymous hemianopsia imaging suggested inadvertent ablation of the lateral geniculate nucleus, although the laser was positioned entirely within the hippocampus. This patient's laser trajectory, ablation number, energy delivered, and ablation size were not significantly different from the prior patients. However, the subject with the visual deficit did have significantly smaller choroidal fissure cerebrospinal fluid volume. Conclusion Visual deficits are the most common complication of LITT for mesiotemporal epilepsy and patients at most risk may have small cerebrospinal fluid volume in the choroidal fissure, allowing heat to spread from the hippocampal body to the lateral geniculate nucleus. When such anatomy is identified on preoperative magnetic resonance imaging, we recommend lowering laser trajectory, decreasing ablation power through the hippocampal body, and using temperature safety markers at the lower thalamic border.

LITT, laser interstitial therapyNd:YAG, neodymium-doped yttrium aluminum.

Deep brain stimulation (DBS) of the subthalamic nucleus is an established therapeutic option for managing motor symptoms of Parkinson's disease. We conducted a double-blind, sham-controlled, randomised controlled trial to assess subthalamic nucleus DBS, with a novel multiple independent contact current-controlled (MICC) device, in patients with Parkinson's disease.This trial took place at 23 implanting centres in the USA. Key inclusion criteria were age between 22 and 75 years, a diagnosis of idiopathic Parkinson's disease with over 5 years of motor symptoms, and stable use of anti-parkinsonian medications for 28 days before consent. Patients who passed screening criteria were implanted with the DBS device bilaterally in the subthalamic nucleus. Patients were randomly assigned in a 3:1 ratio to receive either active therapeutic stimulation settings (active group) or subtherapeutic stimulation settings (control group) for the 3-month blinded period. Randomisation took place with a computer-generated data capture system using a pre-generated randomisation table, stratified by site with random permuted blocks. During the 3-month blinded period, both patients and the assessors were masked to the treatment group while the unmasked programmer was responsible for programming and optimisation of device settings. The primary outcome was the difference in mean change from baseline visit to 3 months post-randomisation between the active and control groups in the mean number of waking hours per day with good symptom control and no troublesome dyskinesias, with no increase in anti-parkinsonian medications. Upon completion of the blinded phase, all patients received active treatment in the open-label period for up to 5 years. Primary and secondary outcomes were analysed by intention to treat. All patients who provided informed consent were included in the safety analysis. The open-label phase is ongoing with no new enrolment, and current findings are based on the prespecified interim analysis of the first 160 randomly assigned patients. The study is registered with ClinicalTrials.gov, NCT01839396.Between May 17, 2013, and Nov 30, 2017, 313 patients were enrolled across 23 sites. Of these 313 patients, 196 (63%) received the DBS implant and 191 (61%) were randomly assigned. Of the 160 patients included in the interim analysis, 121 (76%) were randomly assigned to the active group and 39 (24%) to the control group. The difference in mean change from the baseline visit (post-implant) to 3 months post-randomisation in increased ON time without troublesome dyskinesias between the active and control groups was 3·03 h (SD 4·52, 95% CI 1·3-4·7; p0·0001). 26 serious adverse events in 20 (13%) patients occurred during the 3-month blinded period. Of these, 18 events were reported in the active group and 8 in the control group. One death was reported among the 196 patients before randomisation, which was unrelated to the procedure, device, or stimulation.This double-blind, sham-controlled, randomised controlled trial provides class I evidence of the safety and clinical efficacy of subthalamic nucleus DBS with a novel MICC device for the treatment of motor symptoms of Parkinson's disease. Future trials are needed to investigate potential benefits of producing a more defined current field using MICC technology, and its effect on clinical outcomes.Boston Scientific.

Objective Laser interstitial thermal therapy (LITT) for mesial temporal lobe epilepsy (mTLE) has reported seizure freedom rates between 36% and 78% with at least 1 year of follow-up. Unfortunately, the lack of robust methods capable of incorporating the inherent variability of patient anatomy, the variability of the ablated volumes, and clinical outcomes have limited three-dimensional quantitative analysis of surgical targeting and its impact on seizure outcomes. We therefore aimed to leverage a novel image-based methodology for normalizing surgical therapies across a large multicenter cohort to quantify the effects of surgical targeting on seizure outcomes in LITT for mTLE. Methods This multicenter, retrospective cohort study included 234 patients from 11 centers who underwent LITT for mTLE. To investigate therapy location, all ablation cavities were manually traced on postoperative magnetic resonance imaging (MRI), which were subsequently nonlinearly normalized to a common atlas space. The association of clinical variables and ablation location to seizure outcome was calculated using multivariate regression and Bayesian models, respectively. Results Ablations including more anterior, medial, and inferior temporal lobe structures, which involved greater amygdalar volume, were more likely to be associated with Engel class I outcomes. At both 1 and 2 years after LITT, 58.0% achieved Engel I outcomes. A history of bilateral tonic-clonic seizures decreased chances of Engel I outcome. Radiographic hippocampal sclerosis was not associated with seizure outcome. Significance LITT is a viable treatment for mTLE in patients who have been properly evaluated at a comprehensive epilepsy center. Consideration of surgical factors is imperative to the complete assessment of LITT. Based on our model, ablations must prioritize the amygdala and also include the hippocampal head, parahippocampal gyrus, and rhinal cortices to maximize chances of seizure freedom. Extending the ablation posteriorly has diminishing returns. Further work is necessary to refine this analysis and define the minimal zone of ablation necessary for seizure control.

Background Laser interstitial thermal therapy (LITT) presents an important new minimally invasive tool in the management of drug-resistant mesial temporal epilepsy (MTE). However, because of its relative novelty, not much is known about long-term seizure freedom rates. The objective of this study was to evaluate the postsurgical seizure outcome following LITT after a minimum follow-up period of 2 years. Methods Medical records of all patients who underwent LITT for MTE from 2013 to 2018 at our comprehensive epilepsy center under a single surgeon were retrospectively reviewed. Data related to demographics, presurgical evaluations, and seizure outcome were compared between seizure-free (SF) and non–seizure-free (NSF) patients. Results In all, 26 patients were identified with at least 2 years of follow-up. Mean age was 43.8 years ± 11.6 years, and 46.2% were female. After a mean follow-up time of 42.9 months (range, 24.3–58.8 months), 61.5% (16/26) were free of disabling seizures, and 26.9% (7/26) had only rare disabling seizures. Whereas seizure-freedom rates between patients with and without mesial temporal sclerosis (MTS) were not statistically different (68% vs. 43%, P = 0.23), NSF patients without MTS had a shorter median time to first seizure than did NSF patients with MTS (0.55 month vs. 10 months, log-rank test P = 0.007). Postoperative complications occurred in 2 patients (7.7%), consisting of 1 permanent and 1 transient homonymous hemianopia. Conclusions LITT appears to be a safe and effective initial surgical option for treatment-resistant MTE. Among patients who have seizures after treatment, those without MTS appear to have seizures earlier than those with MTS.

Background: Deep brain stimulation (DBS) is an increasingly utilized technique to treat symptoms of neurological movement disorders, most commonly, Parkinson’s Disease. Patients and surgeons alike appreciate the minimally invasive nature of this procedure, as well as its reversibility. As these surgeries are being performed more often, it is becoming increasingly important to optimize our anesthetic management during these cases. Methods: We conducted a retrospective review of the DBS procedures that have been performed at our institution utilizing monitored anaesthesia care (MAC) via dexmedetomidine infusion to report on the frequency and type of perioperative complications as well as to assess the effectiveness of this technique. Results: A total of 150 patients and 174 lead placements were included in this study. Dexmedetomidine was the sole anaesthetic used in 85.6% of cases. The remaining cases used a combination of dexmedetomidine and adjuvant agents. A total of one perioperative complication was found in our series, resulting in a total complication rate percentage per patient of 0.6%.Conclusions: We found very few perioperative complications associated with the use of dexmedetomidine during these challenging cases. With its anxiolytic, sedative, and analgesic properties coupled with preservation of respiration and a short half-life, dexmedetomidine has ideal properties for DBS procedures.

Frame-based stereotactic lead placement for deep brain stimulation requires a carefully planned trajectory and approach. Point of entry at the cortex is usually selected to be over a gyrus avoiding veins. The angle of lead entry into the skull is different from the perpendicular direction of the burr drill. If the burr hole is not placed properly, the inner plate of the skull may be in the way of the lead, which creates a snowball effect of complications from trajectory readjustment to improperly fitting hardware. Using trigonometric principles, we elucidated a mathematical equation that predicts the precise position of the burr hole in order for the lead to enter exactly in the middle of the opening.