Anticoagulation for the treatment of septic cerebral venous sinus thrombosis in the setting of pediatric sinogenic and otogenic intracranial infections.

OBJECTIVE: Septic cerebral venous sinus thrombosis (CVST) is a recognized complication of pediatric sinogenic and otogenic intracranial infections. The optimal treatment paradigm remains controversial. Proponents of anticoagulation highlight its role in preventing thrombus propagation and promoting recanalization, while others cite the risk of hemorrhagic complications, especially after a neurosurgical procedure for an epidural abscess or subdural empyema. Here, the authors investigated the diagnosis, management, and outcomes of pediatric patients with sinogenic or otogenic intracranial infections and a septic CVST. METHODS: All patients 21 years of age or younger, who presented with an intracranial infection in the setting of sinusitis or otitis media and who underwent neurosurgical treatment at Connecticut Children's, Rady Children's Hospital-San Diego, or Ann and Robert H. Lurie Children's Hospital of Chicago from March 2015 to March 2023, were retrospectively reviewed. Demographic, clinical, and radiological data were systematically collated. RESULTS: Ninety-six patients were treated for sinusitis-related and/or otitis media-related intracranial infections during the study period, 15 (15.6%) of whom were diagnosed with a CVST. Of the 60 patients who presented prior to the COVID-19 pandemic, 6 (10.0%) were diagnosed with a septic CVST, whereas of the 36 who presented during the COVID-19 pandemic, 9 (25.0%) had a septic CVST (p = 0.050). The superior sagittal sinus was involved in 12 (80.0%) patients and the transverse and/or sigmoid sinuses in 4 (26.7%). Only 1 (6.7%) patient had a fully occlusive thrombus. Of the 15 patients with a septic CVST, 11 (73.3%) were initiated on anticoagulation at a median interval of 4 (IQR 3-5) days from the most recent neurosurgical procedure. Five (45.5%) patients who underwent anticoagulation demonstrated complete recanalization on follow-up imaging, and 4 (36.4%) had partial recanalization. Three (75.0%) patients who did not undergo anticoagulation demonstrated complete recanalization, and 1 (25.0%) had partial recanalization. None of the patients treated with anticoagulation experienced hemorrhagic complications. CONCLUSIONS: Septic CVST is frequently identified among pediatric patients undergoing neurosurgical intervention for sinogenic and/or otogenic intracranial infections and may have become more prevalent during the COVID-19 pandemic. Anticoagulation can be used safely in the acute postoperative period if administered cautiously, in a monitored setting, and with interval cross-sectional imaging. However, some patients exhibit excellent outcomes without anticoagulation, and further studies are needed to identify those who may benefit the most from anticoagulation.

Investigating Deep Brain Stimulation of the Habenula: A Review of Clinical Studies.

OBJECTIVES: The aim of this study was to examine the current scientific literature on deep brain stimulation (DBS) targeting the habenula for the treatment of neuropsychiatric disorders including schizophrenia, major depressive disorder, and obsessive-compulsive disorder (OCD). MATERIALS AND METHODS: Two authors performed independent data base searches using the PubMed, Cochrane, PsycINFO, and Web of Science search engines. The data bases were searched for the query ("deep brain stimulation" and "habenula"). The inclusion criteria involved screening for human clinical trials written in English and published from 2007 to 2020. From the eligible studies, data were collected on the mean age, sex, number of patients included, and disorder treated. Patient outcomes of each study were summarized. RESULTS: The search yielded six studies, which included 11 patients in the final analysis. Treated conditions included refractory depression, bipolar disorder, OCD, schizophrenia, and major depressive disorder. Patients with bipolar disorder unmedicated for at least two months had smaller habenula volumes than healthy controls. High-frequency stimulation of the lateral habenula attenuated the rise of serotonin in the dorsal raphe nucleus for treating depression. Bilateral habenula DBS and patient OCD symptoms were reduced and maintained at one-year follow up. Low- and high-frequency stimulation DBS can simulate input paths to the lateral habenula to treat addiction, including cocaine addiction. More data are needed to draw conclusions as to the impact of DBS for schizophrenia and obesity. CONCLUSIONS: The habenula is a novel target that could aid in reducing neuropsychiatric symptoms and should be considered in circuit-specific investigation of neuromodulation for psychiatric disorders. More information needs to be gathered and assessed before this treatment is fully approved for treatment of neuropsychiatric conditions.

Citation analysis of the most influential ependymoma research articles illustrates improved knowledge of the molecular biology of ependymoma.

The history of academic research on ependymoma is expansive. This review summarizes its history with a bibliometric analysis of the 100 most cited articles on ependymoma. In March 2020, we queried the Web of Science database to identify the most cited articles on ependymoma using the terms "ependymoma" or "ependymal tumors," yielding 3145 publications. Results were arranged by the number of times each article was cited in descending order. The top 100 articles spanned across nearly a century; the oldest article was published in 1924, while the most recent was in 2017. These articles were published in 35 unique journals, including a mix of basic science and clinical journals. The three institutions with the most papers in the top 100 were St. Jude Children's Research Hospital (16%), the University of Texas MD Anderson Cancer Center (6%), and the German Cancer Research Center (5%). We analyzed the publications that may be considered the most influential in the understanding and treatment management of ependymoma. Studies focused on the molecular classification of ependymomas were well-represented among the most cited articles, reflecting the field's current area of focus and its future directions. Additionally, this article also offers a reference for further studies in the ependymoma field.

Enhancing peripheral nerve regeneration with neurotrophic factors and bioengineered scaffolds: A basic science and clinical perspective.

Despite the peripheral nervous systems (PNS) capacity to regenerate, functional restoration is highly variable following peripheral nerve injury (PNI), oftentimes leading to persistent functional deficits. In the preclinical arena, advances in the therapeutic use of exogenous neurotrophic factors and synthetic neural scaffold technology hold promise in augmenting endogenous PNS regeneration following PNI. Clinical trials utilizing neurotrophic factors for other indications (eg, peripheral neuropathy) may provide insight into their role in PNI. Here we provide an updated review of progress made toward enhancing regeneration after PNI with a focus on neurotrophic factors and bioengineered scaffolds.

Laser-Assisted Control of Epistaxis in Hereditary Hemorrhagic Telangiectasia: A Systematic Review.

BACKGROUND AND OBJECTIVES: Hereditary hemorrhagic telangiectasia (HHT), also known as Osler-Weber-Rendu disease, causes recurrent mucous membrane hemorrhage, especially epistaxis. In this systematic review, we discuss the efficacies of the three most common laser photocoagulation treatments for HHT-related epistaxis. STUDY DESIGN/MATERIALS AND METHODS: A systematic literature search was conducted in PubMed and MEDLINE from database inception to March 2019. Studies reporting epistaxis outcomes following argon, neodymium-doped yttrium aluminum garnet (Nd:YAG), and diode laser photocoagulation for HHT were included. χ2 and Barnard's exact tests were utilized to detect differences in reduced epistaxis frequency and intensity rates. RESULTS: Fifteen out of 157 published studies met our eligibility criteria, spanning a collective 362 patients. Argon, Nd:YAG, and diode laser therapy reduced epistaxis frequency in 90.4%, 88.9%, and 71.1% of patients, respectively, and reduced epistaxis intensity in 87.8%, 87.2%, and 71.1% of patients, respectively. Diode laser photocoagulation significantly underperformed in both outcome measurements when compared with argon (frequency: P = 0.005; intensity: P = 0.034) and Nd:YAG (frequency: P = 0.012; intensity: P = 0.041). There was no significant difference between argon and Nd:YAG in reducing HHT epistaxis frequency (P = 0.434) or intensity (P = 0.969). Categorizing HHT patients by clinical severity demonstrated a higher rate of improvement in the mild-moderate group compared with the severe group in both argon (P < 0.001) and Nd:YAG (P < 0.001) therapeutic methods. While no significant differences were found in rates of improved epistaxis outcomes between argon and Nd:YAG in mild-moderate HHT patients (frequency: P = 0.061; intensity: P = 0.061), Nd:YAG demonstrated greater rates of reduction in epistaxis frequency (P = 0.040) and intensity (P = 0.028) than argon among severe HHT patients. CONCLUSIONS: HHT is a lifelong disease, plaguing patients with debilitating epistaxis. Intranasal laser photocoagulation of telangiectasias using argon or Nd:YAG laser therapy can yield improved epistaxis outcomes compared with diode laser photocoagulation. In severe cases of HHT, Nd:YAG laser therapy provides greater improvements in epistaxis outcomes than argon photocoagulation. Lasers Surg. Med. © 2019 Wiley Periodicals, Inc.

The role of frailty in geriatric cranial neurosurgery for primary central nervous system neoplasms.

OBJECTIVE: Frailty is a clinical state of increased vulnerability due to age-associated decline and has been well established as a perioperative risk factor. Geriatric patients have a higher risk of frailty, higher incidence of brain cancer, and increased postoperative complication rates compared to nongeriatric patients. Yet, literature describing the effects of frailty on short- and long-term complications in geriatric patients is limited. In this study, the authors evaluate the effects of frailty in geriatric patients receiving cranial neurosurgery for a primary CNS neoplasm. METHODS: The authors conducted a retrospective cohort study of geriatric patients receiving cranial neurosurgery for a primary CNS neoplasm between 2010 and 2017 by using the Nationwide Readmission Database. Demographics and frailty were queried at primary admission, and readmissions were analyzed at 30-, 90-, and 180-day intervals. Complications of interest included infection, anemia, infarction, kidney injury, CSF leak, urinary tract infection, and mortality. Nearest-neighbor propensity score matching for demographics was implemented to identify nonfrail control patients with similar diagnoses and procedures. The analysis used Welch two-sample t-tests for continuous variables and chi-square test with odds ratios. RESULTS: A total of 6713 frail patients and 6629 nonfrail patients were identified at primary admission. At primary admission, frail geriatric patients undergoing cranial neurosurgery had increased odds of developing acute posthemorrhagic anemia (OR 1.56, 95% CI 1.23-1.98; p = 0.00020); acute infection (OR 3.16, 95% CI 1.70-6.36; p = 0.00022); acute kidney injury (OR 1.32, 95% CI 1.07-1.62; p = 0.0088); urinary tract infection prior to discharge (OR 1.97, 95% CI 1.71-2.29; p < 0.0001); acute postoperative cerebral infarction (OR 1.57, 95% CI 1.17-2.11; p = 0.0026); and mortality (OR 1.64, 95% CI 1.22-2.24; p = 0.0012) compared to nonfrail geriatric patients receiving the same procedure. In addition, frail patients had a significantly increased inpatient length of stay (p < 0.0001) and all-payer hospital cost (p < 0.0001) compared to nonfrail patients at the time of primary admission. However, no significant difference was found between frail and nonfrail patients with regard to rates of infection, thromboembolism, CSF leak, dural tear, cerebral infarction, acute kidney injury, and mortality at all readmission time points. CONCLUSIONS: Frailty may significantly increase the risks of short-term acute complications in geriatric patients receiving cranial neurosurgery for a primary CNS neoplasm. Long-term analysis revealed no significant difference in complications between frail and nonfrail patients. Further research is warranted to understand the effects and timeline of frailty in geriatric patients.

Interfacing with the nervous system: a review of current bioelectric technologies.

The aim of this study is to discuss the state of the art with regard to established or promising bioelectric therapies meant to alter or control neurologic function. We present recent reports on bioelectric technologies that interface with the nervous system at three potential sites-(1) the end organ, (2) the peripheral nervous system, and (3) the central nervous system-while exploring practical and clinical considerations. A literature search was executed on PubMed, IEEE, and Web of Science databases. A review of the current literature was conducted to examine functional and histomorphological effects of neuroprosthetic interfaces with a focus on end-organ, peripheral, and central nervous system interfaces. Innovations in bioelectric technologies are providing increasing selectivity in stimulating distinct nerve fiber populations in order to activate discrete muscles. Significant advances in electrode array design focus on increasing selectivity, stability, and functionality of implantable neuroprosthetics. The application of neuroprosthetics to paretic nerves or even directly stimulating or recording from the central nervous system holds great potential in advancing the field of nerve and tissue bioelectric engineering and contributing to clinical care. Although current physiotherapeutic and surgical treatments seek to restore function, structure, or comfort, they bear significant limitations in enabling cosmetic or functional recovery. Instead, the introduction of bioelectric technology may play a role in the restoration of function in patients with neurologic deficits.

Use of interactive iBooks for patient education in otology.

INTRODUCTION: Physicians in the ambulatory setting face challenges in adequately educating patients in a brief office encounter. OBJECTIVE: To evaluate the efficacy of an iPad-based interactive educational module (iBook) in various otologic pathologies. METHODS: Patients presenting with symptoms of tinnitus, dizziness, hearing loss, or cochlear implant evaluation were included. In total, 44 patients received the iBook and 22 patients served as controls. Prior to viewing the iBook, patients completed a pre-survey to assess baseline knowledge. After viewing the iBook, patients completed a post-survey to assess changes in perception and knowledge of their disease. Results were compared to that of the control group who did not receive iBook supplementation prior to being seen by the physician. RESULTS: Paired t-test analysis showed significant improvements (p<0.01) in both self-reported perception and concrete understanding in various concepts when compared to pre-iBook results. This was further compared to the control group, which showed a significant gain in factual knowledge (p=0.02). CONCLUSION: Patients who viewed the iBook, personalized to their diagnosis, displayed significantly improved understanding of their condition. Increased use of interactive educational modalities, such as the iBook, can be of benefit to an otologic practice in improving patient education and satisfaction.

Mild Traumatic Brain Injury and the Auditory System: An Overview of the Mechanisms, Clinical Presentations, and Current Diagnostic Modalities.

The acute and long-term consequences of mild traumatic brain injury (mTBI) are far reaching. Though it may often be overlooked due to the now expansive field of research dedicated to understanding the consequences of mTBI on the brain, recent work has revealed that substantial changes in the vestibulo-auditory system can also occur due to mTBI. These changes, termed "labyrinthine" or "cochlear concussion," include hearing loss, vertigo, and tinnitus that develop after mTBI in the setting of an intact bony labyrinthine capsule (as detected on imaging). In the review that follows, we focus our discussion on the effects of mTBI on the peripheral structures and pathways of the auditory and vestibular systems. Although the effects of indirect trauma (e.g., noise and blast trauma) have been well-investigated, there exists a profound need to improve our understanding of the effects of direct head injury (such as mTBI) on the auditory and vestibular systems. Our aim is to summarize the current evidentiary foundation upon which labyrinthine and/or cochlear concussion are based to shed light on the ways in which clinicians can refine the existing modalities used to diagnose and treat patients experiencing mTBI as it relates to hearing and balance.

The Pterional Keyhole Craniotomy Approach: A Historical Perspective.

The pterional craniotomy is a workhorse of cranial surgery that provides access to the anterior and middle fossae. However, newer "keyhole" approaches, such as the micropterional or pterional keyhole craniotomy (PKC) can offer similar exposure for many pathologies while reducing surgical morbidity. The PKC is associated with shorter hospitalizations, reduced operative time, and superior cosmetic outcomes. Furthermore, it represents an ongoing trend toward smaller craniotomy size for elective cranial procedures. In this historical vignette, we trace the history of the PKC from its origins to its current role in the neurosurgeon's armamentarium.

Utilizing Neuromodulation in the Treatment of Spinal Cord Injury: An Assessment of Clinical Trials from the National ClinicalTrials.gov Database.

OBJECTIVE: Spinal cord injury (SCI) is responsible for approximately 18,000 trauma cases each year in the United States, often resulting in debilitating motor and autonomic disability. Neuromodulation is a rapidly growing field of interest in the neurosurgical field and has additionally shown promise in the treatment of SCI. This review characterizes all clinical trials to date studying neuromodulation for the treatment of SCI. METHODS: The ClinicalTrials.gov database was queried using the search terms "neuromodulation" and "spinal cord injury" on ClinicalTrials.gov. Trials were excluded if they were not yet recruiting, suspended, terminated early, or of unknown status. RESULTS: In total, 33 clinical trials were included in this study. Of the 33 trials, 8 were completed and 1 had published results. Most trials studied deficits of motor function (60%) and bladder control (37%). Fourteen studies (42.4%) utilized transcutaneous spinal stimulation, 7 (21.2%) utilized epidural electrical stimulation, and 6 (18.2%) utilized tibial nerve stimulation. There was an uptrend of clinical trials studying SCI indexed on PubMed, which was comparable to the increased number of publications indexed overall (Pearson correlation, P < 0.001). Of these, only 1 study regarding home tibial nerve stimulation for neurogenic bladder had published data, which was performed with no adverse events. CONCLUSIONS: Neuromodulation in SCI studies currently assess transcutaneous spinal stimulation, epidural electrical stimulation, and tibial nerve stimulation. There is currently 1 completed study suggesting feasibility of home neuromodulation techniques without adverse events. The results of trials that will be completed in the next few years will help dictate the potential of neuromodulation as a treatment for SCI.

Surgical Intervention for Primary B-cell Lymphoma of the Spine: A Systematic Review and Meta-analysis of Clinical Presentation, Treatment, Postoperative Outcomes, and Histologic Markers.

STUDY DESIGN: Systematic review and meta-analysis. OBJECTIVE: To perform a systematic review of the clinical symptoms, radiographic findings, and outcomes after spinal decompression in B-cell lymphoma. SUMMARY OF BACKGROUND DATA: B-cell lymphoma is a potential cause of spinal cord compression that presents ambiguously with nonspecific symptoms and variable imaging findings. Surgical decompression is a mainstay for both diagnosis and management, especially in patients with acute neurological deficits; however, the efficacy of surgical intervention compared with nonoperative management is still unclear. METHODS: The databases of Medline, PubMed, and the Cochrane Database of Systemic Reviews were queried for all articles reporting spinal B-cell lymphoma. Data on presenting symptoms, treatments, survival outcomes, and histologic markers were extracted. Using the R software "survival" package, we generated bivariate and multivariate Cox survival regression models and Kaplan-Meier curves. RESULTS: In total, 65 studies were included with 72 patients diagnosed with spinal B-cell lymphoma. The mean age was 56.22 (interquartile range: 45.00-70.25) with 68% of patients being males and 4.2% of patients being immunocompromised. Back pain was the most common symptom (74%), whereas B symptoms and cauda equina symptoms were present in 6% and 29%, respectively. The average duration of symptoms before presentation was 3.81 months (interquartile range: 0.45-3.25). The most common location was the thoracic spine (53%), with most lesions being hyperintense (28%) on T2 magnetic resonance imaging. Surgical resection was performed in 83% of patients. Symptoms improved in 91% of patients after surgery and in 80% of patients treated nonoperatively. For all 72 patients, the overall survival at 1 and 5 years was 85% (95% CI: 0.749-0.953; n = 72) and 66% (95% CI: 0.512-0.847; n = 72), respectively. CONCLUSION: Although surgery is usually offered in patients with acute spinal cord compression from B-cell lymphoma, chemotherapy and radiation alone offer a hopeful alternative to achieve symptomatic relief, particularly in patients who are unable to undergo surgery.

Application of Responsive Neurostimulation as both a Diagnostic Tool for Seizure Localization and a Supplementary Tool for Surgical Management in Patients with Multiple Epileptogenic Foci: A Case Series.

AIM: To present a series of medically refractory focal epilepsy patients with multiple or eloquent epileptogenic zones (EZs) in whom a responsive neurostimulation (RNS) system was used as a complementary modality to surgical resection. RNS was also used as a diagnostic tool to monitor long-term epileptogenic activity for enhanced localization, especially in patients with bilateral temporal seizures. MATERIAL AND METHODS: Ten consecutive patients who underwent RNS system placement and surgical resection at a single institution were assessed. RESULTS: The RNS system, with its capacity for chronic ambulatory electrocorticography (ECoG), provided important diagnostic information that helped to modify the plan of surgical resection in one patient with bitemporal epilepsy in order to improve seizure outcomes. In addition, the RNS facilitated the surgical management of patients with multiple or eloquent EZs. CONCLUSION: The authors report a population of 10 patients in which the RNS system was used as a diagnostic tool for improved localization of EZs over a long interval or as a complementary therapeutic tool in patients with multiple or eloquent EZs.

The Current State of Radiotherapy for Pediatric Brain Tumors: An Overview of Post-Radiotherapy Neurocognitive Decline and Outcomes.

Tumors of the central nervous system are the most common solid malignancies diagnosed in children. While common, they are also found to have some of the lowest survival rates of all malignancies. Treatment of childhood brain tumors often consists of operative gross total resection with adjuvant chemotherapy or radiotherapy. The current body of literature is largely inconclusive regarding the overall benefit of adjuvant chemo- or radiotherapy. However, it is known that both are associated with conditions that lower the quality of life in children who undergo those treatments. Chemotherapy is often associated with nausea, emesis, significant fatigue, immunosuppression, and alopecia. While radiotherapy can be effective for achieving local control, it is associated with late effects such as endocrine dysfunction, secondary malignancy, and neurocognitive decline. Advancements in radiotherapy grant both an increase in lifetime survival and an increased lifetime for survivors to contend with these late effects. In this review, the authors examined all the published literature, analyzing the results of clinical trials, case series, and technical notes on patients undergoing radiotherapy for the treatment of tumors of the central nervous system with a focus on neurocognitive decline and survival outcomes.

Selective Facial Muscle Activation with Acute and Chronic Multichannel Cuff Electrode Implantation in a Feline Model.

OBJECTIVES: Facial paralysis is a debilitating condition with substantial functional and psychological consequences. This feline-model study evaluates whether facial muscles can be selectively activated in acute and chronic implantation of 16-channel multichannel cuff electrodes (MCE). METHODS: Two cats underwent acute terminal MCE implantation experiments, 2 underwent chronic MCE implantation in uninjured facial nerves (FN) and tested for 6 months, and 2 underwent chronic MCE implantation experiments after FN transection injury and tested for 3 months. The MCE were wrapped around the main trunk of the skeletonized FN, and data collection consisted of EMG thresholds, amplitudes, and selectivity of muscle activation. RESULTS: In acute experimentation, activation of specific channels (ie, channels 1-3 and 6-8) resulted in selective activation of orbicularis oculi, whereas activation of other channels (ie, channels 4, 5, or 8) led to selective activation of levator auris longus with higher EMG amplitudes. MCE implantation yielded stable and selective facial muscle activation EMG thresholds and amplitudes up to a 5-month period. Modest selective muscle activation was furthermore obtained after a complete transection-reapproximating nerve injury after a 3-month recovery period and implantation reoperation. Chronic implantation of MCE did not lead to fibrosis on histology. Field steering was achieved to activate distinct facial muscles by sending simultaneous subthreshold currents to multiple channels, thus theoretically protecting against nerve damage from chronic electrical stimulation. CONCLUSION: Our proof-of-concept results show the ability of an MCE, supplemented with field steering, to provide a degree of selective facial muscle stimulation in a feline model, even following nerve regeneration after FN injury. LEVEL OF EVIDENCE: N/A.

Treatment selection towards active surveillance over definitive treatment for pituitary adenomas is influenced by sociodemographic factors.

BACKGROUND: Clinical and sociodemographic predictors of pituitary adenoma (PA) patients undergoing active surveillance (AS) versus definitive treatment (DT) are poorly understood. OBJECTIVE: This population-based analysis aims to identify clinical and sociodemographic predictors of undergoing AS versus DT. METHODS: The National Cancer Database (NCDB) was utilized to query PA patients diagnosed from 2010 to 2015 undergoing AS or DT. Independent-samples t-test and chi-squared test were used to compare differences in patient baseline characteristics and a stepwise binary logistic regression was performed to elucidate factors implicated in undergoing AS. RESULTS: The cohort consisted of 30,233 PA patients, with 5147 (17.0%) patients undergoing AS. On multivariable logistic regression, patients aged ≥ 65 years (OR=1.65; p < 0.001), African American race (OR=1.12; p = 0.035), having government insurance (OR=1.45; p < 0.001) or those uninsured (OR=1.58; p < 0.001) were significantly more likely to undergo AS compared to DT, while patients with larger tumors (OR=0.90; p < 0.001), receiving treatment at academic facilities (OR=0.75; p < 0.001), and living in West regions of the United States (OR=0.59; p < 0.001) were significantly less likely to undergo AS compared to DT. CONCLUSIONS: Significant sociodemographic disparities exist in patient selection for undergoing AS versus DT, which may modify patient clinical outcomes.

Selective Neural Electrical Stimulation of an Injured Facial Nerve Using Chronically Implanted Dual Cuff Electrodes.

Facial nerve (FN) injury can lead to debilitating and permanent facial paresis/paralysis (FP), where facial muscles progressively lose tone, atrophy, and ultimately reduce to scar tissue. Despite considerable efforts in the recent decades, therapies for FP still possess high failure rates and provide inadequate recovery of muscle function. In this pilot study, we used a feline model to demonstrate the potential for chronically implanted multichannel dual-cuff electrodes (MCE) to selectively stimulate injured facial nerves at low current intensities to avoid stimulus-induced neural injury. Selective facial muscle activation was achieved over six months after FN injury and MCE implantation in two domestic shorthaired cats (Felis catus). Through utilization of bipolar stimulation, specific muscles were activated at significantly lower electrical currents than was achievable with single channel stimulation. Moreover, interval increases in subthreshold current intensities using bipolar stimulation enabled a graded EMG voltage response while maintaining muscle selectivity. Histological examination of neural tissue at implant sites showed no appreciable signs of stimulation-induced nerve injury. Thus, by selectively activating facial musculature six months following initial FN injury and MCE implantation, we demonstrated the potential for our neural stimulator system to be safely and effectively applied to the chronic setting, with implications for FP treatment.

The minimally conscious state: an analysis of current clinical trials registered in ClinicalTrials.gov.

The minimally conscious state (MCS) is a disorder of consciousness described in recent years for patients who have behavioral responses to stimuli that do not meet the classification of chronic vegetative state (CVS) or coma. This distinction is valuable in clinical practice, as minimally conscious patients may require different treatments and may have different long-term outcomes when compared to vegetative states or coma. In this report, we analyzed the ClinicalTrials.gov database to systematically assess all clinical trials regarding MCS. The database was queried using the term "minimally conscious state" in the "condition or disease" search parameter. Of the studies identified, those that had suspended, terminated, or otherwise unknown statuses were excluded. In total, 41 studies were analyzed. The included studies were initiated between 2008 and 2020, with the majority (63%) beginning in 2015 or later. Of the primary intervention modalities included, 15 (37%) evaluated stimulation modalities such as transcranial magnetic stimulation, transcranial direct current stimulation, implantable neurostimulation, vagus nerve stimulation, focused ultrasound and median nerve stimulation. Additionally, 5 (12%) used some form of behavioral therapy. A total of 4 (10%) studies involved pharmaceutical intervention, including dopamine agonists, analgesics and sedatives. Finally, 4 (10%) studies sought to determine the validity of current diagnostic methods and systems used to assess the status of patients in MCSs. Since the definition and criteria for CVS and MCS have been established, these two conditions remain closely associated despite evidence of different patient outcomes and treatment options. Many clinical trials are underway assessing interventions with stimulation. However, the trials are lacking with respect to diagnostic methods and pharmaceutical treatment.

Bony fixation in the era of spinal robotics: A systematic review and meta-analysis.

BACKGROUND: Accurate spinal screw placement in spinal instrumentation is of utmost importance to avoid injury to surrounding neurovascular structures. This study was performed to investigate differences in accuracy, operating room time, length of stay, and operative blood loss across studies involving all types of spinal fixation. METHODS: PubMed, EMBASE, and Scopus were systematically queried to identify articles that fit the inclusion and exclusion criteria. Meta-analysis was performed using R software, and odds ratios and 95% CIs were calculated. RESULTS: Sixty-nine articles were included in qualitative synthesis, and 35 studies in the meta-analysis, for a total of 8,174 robotically placed screws in 1,492 patients compared to 9,791 conventionally placed screws in 1,638 patients. A total of 9 screw trajectories were studied in the literature, although only 4 had enough evidence to be included in the meta-analysis. Robotic screw placement was more accurate than conventional screw placement (OR 2.24; 95% CI, 1.71-2.94). Robotic placement was not associated with significantly different postoperative length of stay (SMD -0.32; 95% CI, -1.20, 0.51), operative blood loss (SMD -0.25; 95% CI, -0.79, 0.19), or operative duration (SMD 0.08; 95% CI -1.00, 1.39). A total of 8 robotic platforms were found in the literature with accuracy rates above 93%. CONCLUSION: Robotic spinal fixation is associated with increased screw placement accuracy and similar operative blood loss, length of stay, and operative duration. These findings support the safety and cost-effectiveness of robotic spinal surgery across the spectrum of robotic systems and screw types.

Use of Tranexamic Acid for Elective Resection of Intracranial Neoplasms: A Systematic Review.

BACKGROUND: As an established antifibrinolytic agent, tranexamic acid (TXA) has garnered widespread use during surgery to limit intraoperative blood loss. In the field of neurosurgery, TXA is often introduced in cases of traumatic brain injury or elective spine surgeries; however, its role during elective cranial surgeries is not well established. We report a systematic review of the use of TXA in elective surgical resection of intracranial neoplasms. METHODS: We performed this systematic review following PRISMA guidelines to identify studies investigating the use of TXA in elective neurosurgical resection of intracranial neoplasms. Variables extracted included patient demographics, surgical indications, type of surgery performed, TXA dose and route of administration, operative duration, blood loss, transfusion rate, postoperative hemoglobin level, and complications. RESULTS: After careful screening, 4 articles (consisting of 682 patients) met our inclusion/exclusion criteria. The studies included 2 prospective cohort studies, 1 retrospective cohort study, and 1 case series. A χ2 test of pooled data demonstrated that patients administered TXA had a significantly decreased need for blood transfusions during surgery (odds ratio, 0.6273; 95% confidence interval, 0.4254-0.9251; P = 0.018). Mean total blood loss was 821.9 mL in the TXA group and 1099.0 mL in the control group across the studies. There was no significant difference in postoperative hemoglobin levels, with a mean of 11.4 g/dL in both the TXA and control groups. CONCLUSIONS: These results support the use of intraoperative TXA in tumor resection. However, its role in tumor resection has been less well investigated compared with its use in other areas of neurosurgery.