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Objective: Lumbar pedicle screw placement surgery involves various assistive technologies, including fluoroscopic, stereotactic, or robotic navigation and intraoperative neuromonitoring (IONM). We aimed to discern neurosurgeons' preferences for screw placement techniques and IONM utility, while also considering the influence of experience., Methods: A survey was distributed to members of the Congress of Neurological Surgeons using REDCap software, collecting demographic data and querying preferred techniques for screw placement and IONM modalities. Opinions on IONM use during stereotactic or robotic navigation were also obtained. Responses were analyzed using Pearson's Chi-square and analysis of variance tests via R software., Results: Of 188 responses, 35.5% (n = 67) reported 1-10 years of experience and 64.5% (n = 121) reported ≥ 11 years. Less experienced neurosurgeons used stereotactic navigation more than those with greater experience (P < 0.001). Seasoned neurosurgeons used fluoroscopic guidance more often (P = 0.038). Less experienced neurosurgeons employed 1.69 (± 0.11) techniques for their fixation surgeries compared to 1.50 (± 0.0.8) for more experienced neurosurgeons. Robotic navigation utilization was low and comparable between the groups. Surgeons employing multiple techniques used triggered electromyography the most (62.1%, P = 0.024). No strong opinions emerged on the necessity of multimodality IONM with robotic or stereotactic navigation., Conclusions: This national survey shows that stereotactic navigation is the predominant technique for pedicle screw placement among less experienced neurosurgeons, with seasoned neurosurgeons leaning toward fluoroscopic guidance. Robotic guidance was the least used technique with no observed difference based on experience. Neurosurgeons employing multiple techniques use IONM the most, compared with surgeons who only use stereotactic navigation and/or robotic guidance., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Organophosphates (OP), commonly used in agriculture and as chemical warfare agents, pose significant environmental risks, necessitating real-time, low-cost OP detection methods. In particular, liquid-phase OP sensing with minimal sample volumes is crucial. While several methods allow rapid detection of low concentrations of OP vapors, they are effective only in the short term, while vapors are still being produced. Many OP compounds are semi-volatile, leading to the contamination of water, soil, and surfaces, posing a risk of secondary, long-term exposure. Detecting this contamination requires methods that can be directly applied to droplets of the affected medium. Currently, no method provides the desired combination of ultra-sensitivity, quantitative detection, rapid response, and low-cost for detecting OPs in liquid samples. This study aims to demonstrate quantitative, low-cost, real-time, specific, and label-free OP sensing in ultra-small samples using a transistor-based approach. The current work employs the 2-(4-Aminophenyl)-1,1,1,3,3,3-hexafluoro-2-propanol (aminophenyl-HFIP) functionalized meta-nano-channel field-effect chemical sensor (MNChem sensor) to monitor the organophosphate, diethyl cyanophosphonate (DCNP), in liquid samples. The silicon component of the MNChem is fabricated using a complementary metal-oxide semiconductor (CMOS) process, and the amine-based chemical functionalization of the sensing area is performed post-fabrication. The MNChem sensor provides electrostatic control over the source-drain current (I DS ), allowing an optimized channel configuration that efficiently transduces localized OP recognition events into significant I DS variations. Sensing is performed using 0.5 μL buffer solution to simulate a miniature field-deployable sensor for on-site liquid analysis. We report the sensing of DCNP with a limit-of-detection of 100 fg/mL, a dynamic range of 9 orders of magnitude, and excellent linearity (≥0.97) and sensitivity. Control measurements confirm the specificity and reliability of the sensor's response, validating its applicability. This study introduces a novel method for OP detection in contaminated droplets using a low-cost disposable transistor technology., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Gil Shalev reports financial support was provided by The study was funded by the Israeli Ministry of Defense CBRN Defense Division. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Objective: Excessive consumption of added sugars has been linked to the rise in obesity and associated metabolic abnormalities. Non-nutritive sweeteners (NNSs) offer a potential solution to reduce sugar intake, yet their metabolic safety remains debated. This study aimed to systematically assess the long-term metabolic effects of commonly used NNSs under both normal and obesogenic conditions., Methods: To ensure consistent sweetness level and controlling for the acceptable daily intake (ADI), eight weeks old C57BL/6 male mice were administered with acesulfame K (ace K, 535.25 mg/L), aspartame (411.75 mg/L), sucralose (179.5 mg/L), saccharin (80 mg/L), or steviol glycoside (Reb M, 536.25 mg/L) in the drinking water, on the background of either regular or high-fat diets (in high fat diet 60% of calories from fat). Water or fructose-sweetened water (82.3.gr/L), were used as controls. Anthropometric and metabolic parameters, as well as microbiome composition, were analyzed following 20-weeks of exposure., Results: Under a regular chow diet, chronic NNS consumption did not significantly affect body weight, fat mass, or glucose metabolism as compared to water consumption, with aspartame demonstrating decreased glucose tolerance. In diet-induced obesity, NNS exposure did not increase body weight or alter food intake. Exposure to sucralose and Reb M led to improved insulin sensitivity and decreased weight gain. Reb M specifically was associated with increased prevalence of colonic Lachnospiracea bacteria., Conclusions: Long-term consumption of commonly used NNSs does not induce adverse metabolic effects, with Reb M demonstrating a mild improvement in metabolic abnormalities. These findings provide valuable insights into the metabolic impact of different NNSs, aiding in the development of strategies to combat obesity and related metabolic disorders., Competing Interests: Declaration of competing interest None., (Copyright © 2024 The Authors. Published by Elsevier GmbH.. All rights reserved.)

Transistor-based biosensing (BioFET) is a long-enduring vision for next generation medical diagnostics. The study addresses a challenge associated with the BioFET solution gating. The standard BioFET sensing measurement involves sweeping of the solution gate (V sol ) with a concurrent measurement of the source-drain current (I DS ). This I DS -V sol sweep poses a great challenge, as V sol does not only determine I DS , but also determines the pH levels, ion concentrations, and electric fields at the sensing area double layer accommodating the biomolecules. Therefore, inevitably, an I DS -V sol sweep implies that the sensing area double layer is not in an electrochemical equilibrium, but rather in a continuous transient state as electrochemical potential gradients induce transient ion currents continuously affecting double layer hosting the biomolecules and the biological interactions. This challenge calls for a BioFET design which permits I DS sweeping from an off-state to an on-state while keeping V sol constant and the double layer sensing area in electrochemical equilibrium. The study explores a BioFET design addressing this challenge by decoupling the solution potential from I DS gating. Specific and label-free sensing of ferritin in 0.5 μL drops of 1:100 diluted plasma is pursued. We show an excellent sensing performance once the solution potential and I DS gating are decoupled, with a limit-of-detection of 10 fg/ml, a dynamic range of 10 orders of magnitude in ferritin concentration and excellent linearity and sensitivity. In contrast, a poor sensing performance is recorded for the conventional V sol sweep performed in parallel to the above. Extensive control measurements quantifying the non-specific signals are reported., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Biosensing with biological field-effect transistors (bioFETs) is a promising technology toward specific, label-free, and multiplexed sensing in ultra-small samples. The current study employs the field-effect meta-nano-channel biosensor (MNC biosensor) for the detection of the enzyme N-acetyl-beta-D-glucosaminidase (NAGase), a biomarker for milk cow infections. The measurements are performed in a 0.5 μL drops of 3% commercial milk spiked with NAGase concentrations in the range of 30.3 aM-3.03 μM (Note that there is no background NAGase concentration in commercial milk). Specific and label-free sensing of NAGase is demonstrated with a limit-of-detection of 30.3 aM, a dynamic range of 11 orders of magnitude and with excellent linearity and sensitivity. Additional two important research outcomes are reported. First, the ionic strength of the examined milk is ∼120 mM which implies a bulk Debye screening length <1 nm. Conventionally, a 1 nm Debye length excludes the possibility of sensing with a recognition layer composed of surface bound anti-NAGase antibodies with a size of ∼10 nm. This apparent contradiction is removed considering the ample literature reporting antibody adsorption in a predominantly surface tilted configuration (side-on, flat-on, etc.). Secondly, milk contains a non-specific background protein concentration of 33 mg/ml, in addition to considerable amounts of micron-size heterogeneous fat structures. The reported sensing was performed without the customarily exercised surface blocking and without washing of the non-specific signal. This suggests that the role of non-specific adsorption to the BioFET sensing signal needs to be further evaluated. Control measurements are reported., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Background: Spinal anesthesia (SA) is used in lumbar surgery, but initial adequate analgesia fails in some patients. In these cases, spinal redosing or conversion to general endotracheal anesthesia is required, both of which are detrimental to the patient experience and surgical workflow., Methods: We reviewed cases of lumbar surgery performed under SA from 2017-2021. We identified 12 cases of inadequate first dose and then selected 36 random patients as controls. We used a measurement tool to approximate the volume of the dural sac for each patient using T2-weighted sagittal magnetic resonance imaging sequences., Results: Patients who had an inadequate first dose of anesthesia had a significantly larger dural sac volume, 22.8 ± 7.9 cm 3 in the inadequate dose group and 17.4 ± 4.7 cm 3 in controls (P = 0.043). The inadequate dose group was significantly younger, 54.2 ± 8.8 years in failed first dose and 66.4 ± 11.9 years in controls (P = 0.001). The groups did not differ by surgical procedure (P = 0.238), level (P = 0.353), American Society of Anesthesia score (P = 0.546), or comorbidities., Conclusions: We found that age, larger height, and dural sac volume are risk factors for an inadequate first dose of SA. The availability of spinal magnetic resonance imaging in patients undergoing spine surgery allows the preoperative measurement of their thecal sac size. In the future, these data may be used to personalize spinal anesthesia dosing on the basis of individual anatomic variables and potentially reduce the incidence of failed spinal anesthesia in spine surgery., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Hydrocephalus is rarely described in Joubert-Boltshauser syndrome (JBTS). The aim of this study was to investigate whether this association is a chance occurrence or potentially signifies a new phenotypic subtype. The databases of Wolfson Medical Center, Sourasky Medical Center, and EB's personal collection were reviewed. Records from an additional family were obtained from RG. The patients' medical records, prenatal ultrasounds, and magnetic resonance imaging were assessed. In addition, we reviewed the medical literature for the association of ventriculomegaly/hydrocephalus (VM/HC) in JBTS. Only seven cases (from five families) were found with prenatal onset of VM/HC, diagnosed during the second trimester; three pregnancies were terminated, one was stillborn and three were born, of which one died within a week, and another died at the age of 6 years. Additional central nervous system findings included dysgenesis of the corpus callosum, delayed sulcation, polymicrogyria, and pachygyria. We found 16 publications describing 54 patients with JBTS and VM/HC: only five were diagnosed at birth and three were diagnosed prenatally. Hydrocephalus is extremely rare in JBTS. The recurrence of this association, reported in several publications in multiple family members, suggests that it might represent a new phenotypic subtype of JBTS possibly associated with specific genes or variants. Further genetic studies are needed to confirm this hypothesis. WHAT THIS PAPER ADDS: The association of fetal hydrocephalus with Joubert-Boltshauser syndrome (JBTS) is very rare but not a chance association. This association represents a new phenotypic subtype of JBTS possibly linked to specific genes or variants., (© 2024 The Authors. Developmental Medicine & Child Neurology published by John Wiley & Sons Ltd on behalf of Mac Keith Press.)

Objective: The erector spinae plane block (ESPB) is a novel regional analgesic technique which improves postoperative outcomes in lumbar surgery patients including length of hospitalization, days to ambulation, and postoperative opioid use. Traditionally, the block is administered by anesthesiologists trained in the ultrasound guidance technique. The use of fluoroscopic guidance may improve the efficiency and accessibility of the ESPB for spine surgeons. We aim to measure the time to administer an ESPB using fluoroscopic guidance and localize the anesthetic using intraoperative three-dimensional (3D) imaging., Methods: Two neurosurgeons administered an ESPB to patients undergoing lumbar surgery. Time from insertion of the spinal needle to localize the erector spinae plane using C-arm guidance to time of complete injection and removal of the needle from the skin was recorded. One patient underwent O-arm imaging following injection of an Isovue-Exparel solution at the L3 level to visualize spread of the anesthetic., Results: A total of 21 patients were enrolled in this study. The average duration to perform an ESPB under fluoroscopic guidance was 1.2 minutes. The Isovue-Exparel solution was injected at the L3 level and was well distributed along the ESP on intraoperative O-arm imaging. The anesthetic dissected the erector spinae muscle from the transverse process at L2, L3, and L4., Conclusions: Fluoroscopic guidance allows efficient and appropriate delivery of the anesthetic to the erector spinae plane. Performing an ESPB with fluoroscopic guidance improves efficiency and accessibility of the analgesic technique for spine surgeons, reducing dependence on anesthesiology personnel trained in administering the block., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Background: Polypharmacy and opioid administration are thought to increase the risk of postoperative cognitive dysfunction and delirium in elderly patients. Spinal anesthesia (SA) holds potential to reduce perioperative polypharmacy in spine surgery. As more geriatric patients undergo spine surgery, understanding how SA can reduce polypharmacy and opioid administration is warranted. We aim to compare the perioperative polypharmacy and dose of administered opioids in patients ≥65 years who undergo transforaminal lumbar interbody fusion (TLIF) under SA versus general anesthesia (GA)., Methods: A retrospective analysis of 200 patients receiving a single-surgeon TLIF procedure at a single academic center (2014-2021) was performed. Patients underwent the procedure with SA (n = 120) or GA (n = 80). Demographic, procedural, and medication data were extracted from the medical record. Opioid consumption was quantified as morphine milligram equivalents (MME). Statistical analyses included χ 2 or Student's t-test., Results: Patients receiving SA were administered 7.45 medications on average versus 12.7 for GA patients (P < 0.001). Average perioperative opioid consumption was 5.17 MME and 20.2 MME in SA and GA patients, respectively (P < 0.001). The number of patients receiving antiemetics and opioids remained comparable postoperatively, with a mean of 32.2 MME in the GA group versus 27.5 MME in the SA group (P = 0.14). Antiemetics were administered less often as a prophylactic in the SA group (32%) versus 86% in the GA group (P < 0.001)., Conclusions: SA reduces perioperative polypharmacy in patients ≥65 years undergoing TLIF procedures. Further research is necessary to determine if this reduction correlates to a decrease the incidence of postoperative cognitive dysfunction and delirium., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Demographic histories are frequently a product of the environment, as populations expand or contract in response to major environmental changes, often driven by changes in climate. Meso- and bathy-pelagic fishes inhabit some of the most temporally and spatially stable habitats on the planet. The stability of the deep-pelagic could make deep-pelagic fishes resistant to the demographic instability commonly reported in fish species inhabiting other marine habitats, however the demographic histories of deep-pelagic fishes are unknown. We reconstructed the historical demography of 11 species of deep-pelagic fishes using mitochondrial and nuclear DNA sequence data. We uncovered widespread evidence of population expansions in our study species, a counterintuitive result based on the nature of deep-pelagic ecosystems. Frequency-based methods detected potential demographic changes in nine species of fishes, while extended Bayesian skyline plots identified population expansions in four species. These results suggest that despite the relatively stable nature of the deep-pelagic environment, the fishes that reside here have likely been impacted by past changes in climate. Further investigation is necessary to better understand how deep-pelagic fishes, by far Earth's most abundant vertebrates, will respond to future climatic changes., Competing Interests: The authors declare that they have no conflicts of interest., (© 2024 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd.)

Antibody-antigen interactions are shaped by the solution pH level, ionic strength, and electric fields, if present. In biological field-effect transistors (BioFETs), the interactions take place at the sensing area in which the pH level, ionic strength and electric fields are determined by the Poisson-Boltzmann equation and the boundary conditions at the solid-solution interface and the potential applied at the solution electrode. The present study demonstrates how a BioFET solution electrode potential affects the sensing area double layer pH level, ionic strength, and electric fields and in this way shapes the biological interactions at the sensing area. We refer to this as 'active sensing'. To this end, we employed the meta -nano-channel (MNC) BioFET and demonstrate how the solution electrode can determine the antibody-antigen equilibrium constant and allows the control and tuning of the sensing performance in terms of the dynamic range and limit-of-detection. In the current work, we employed this method to demonstrate the specific and label-free sensing of Alpha-Fetoprotein (AFP) molecules from 0.5 μL drops of 1 : 100 diluted serum. AFP was measured during pregnancy as part of the prenatal screening program for fetal anomalies, chromosomal abnormalities, and abnormal placentation. We demonstrate AFP sensing with a limit-of-detection of 10.5 aM and a dynamic range of 6 orders of magnitude in concentration. Extensive control measurements are reported.

Background and Objectives: Greater thecal sac volumes are associated with an increased risk of spinal anesthesia (SA) failure. The thecal sac cross-sectional area accurately predicts thecal sac volume. The thecal sac area may be used to adjust the dose and prevent anesthetic failure. We aim to assess the rate of SA failure in a prospective cohort of lumbar surgery patients who receive an individualized dose of bupivacaine based on preoperative measurement of their thecal sac area., Methods: A total of 80 patients prospectively received lumbar spine surgery under SA at a single academic center (2022-2023). Before surgery, the cross-sectional area of the thecal sac was measured at the planned level of SA injection using T2-weighted MRI. Patients with an area <175 mm2, equal to or between 175 and 225 mm2, and >225 mm2 received an SA injection of 15, 20, or 25 mg of 0.5% isobaric bupivacaine, respectively. Instances of anesthetic failure and adverse outcomes were noted. Incidence of SA failure was compared with a retrospectively obtained control cohort of 250 patients (2019-2022) who received the standard 15 mg of bupivacaine., Results: No patients in the individualized dose cohort experienced failure of SA compared with 14 patients (5.6%) who experienced failure in the control cohort (P = .0259). The average thecal sac area was 187.49 mm2, and a total 28 patients received 15 mg of bupivacaine, 42 patients received 20 mg of bupivacaine, and 10 patients received 25 mg of bupivacaine. None of the patients experienced any adverse outcomes associated with SA. Patients in the individualized dose cohort and control cohort were comparable and had a similar distribution of lumbar procedures and comorbidities., Conclusion: Adjusting the dose of SA according to thecal sac area significantly reduces the rate of SA failure in patients undergoing lumbar spine surgery., (Copyright © Congress of Neurological Surgeons 2024. All rights reserved.)

Purpose: Because of the concerns regarding residency process during the pandemic, this study aimed to investigate the volume of clinical interactions of orthopaedic residents at a tertiary hospital by reporting the number of patients treated in the outpatient clinic, inpatient ward, and operating room., Methods: This retrospective chart study evaluated variables such as volume of clinical interactions of orthopaedic residents at a tertiary hospital by reporting the number of patients treated in the outpatient clinic, inpatient ward, and operating room, from an orthopaedic department in a tertiary trauma center throughout the COVID-19 pandemic era. Comparing these measures was an indirect evaluation tool for measuring the amount of work completed and clinical exposure gained by the residents., Results: Occupancy percentage, hospitalization days, admissions to the department, and attendance of the outpatient clinic were all decreased during the pandemic. No significant changes were evident in the total number of surgeries nor the number of elective surgeries during the pandemic., Conclusions: Overall, a reduction in overall hospitalization days, admissions to the department, total number of visits in the outpatient clinic, and occupancy percentage of the ward was observed during COVID-19. However, there was no difference in the average number of monthly surgeries between the pre-COVID-19 and COVID-19 timeframes., Level of Evidence: Level III, retrospective comparative review., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. Full ICMJE author disclosure forms are available for this article online, as supplementary material., (© 2023 The Authors.)

As some of the smallest vertebrates, yet largest producers of consumed reef biomass, cryptobenthic reef fishes serve a disproportionate role in reef ecosystems and are one of the most poorly understood groups of fish. The blenny genera Hypleurochilus and Parablennius are currently considered paraphyletic and the interrelationships of Parablennius have been the focus of recent phylogenetic studies. However, the interrelationships of Hypleurochilus remain understudied. This genus is transatlantically distributed and comprises 11 species with a convoluted taxonomic history. In this study, relationships for ten Hypleurochilus species are resolved using multi-locus nuclear and mtDNA sequence data, morphological data, and mined COI barcode data.  Mitochondrial and nuclear sequence data from 61 individuals collected from the western Atlantic and northern Gulf of Mexico (N. GoM) delimit seven species into a temperate clade, a tropical clade, and a third distinct lineage. This lineage, herein referred to as H. cf. aequipinnis, may represent a species of Hypleurochilus whose range has expanded into the N. GoM. Inclusion of publicly available COI sequence for an additional three species provides further phylogenetic resolution. H. bananensis forms a new eastern Atlantic clade with H. cf. aequipinnis, providing further evidence for a western Atlantic range expansion. Single marker COI delimitation was unable to elucidate the relationships between H. springeri/H. pseudoaequipinnis and between H. multifilis/H. caudovittatus due to incomplete lineage sorting. Mitochondrial data are also unable to accurately resolve the placement of H. bermudensis. However, a comprehensive approach using multi-locus phylogenetic and species delimitation methods was able to resolve these relationships. While mining publicly available sequence data allowed for the inclusion of an increased number of species in the analysis and a more comprehensive phylogeny, it was not without drawbacks, as a handful of sequences are potentially mis-identified. Overall, we find that the recent divergence of some species within this genus and potential introgression events confound the results of single locus delimitation methods, yet a combination of single and multi-locus analyses has allowed for insights into the biogeography of this genus and uncovered a potential transatlantic range expansion., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Aims: One of the most common complications of pregnancy is gestational diabetes mellitus (GDM), which may result in significant health threats of the mother, fetus and the newborn. Fatty acid-binding protein 4 (FABP4) is an adipokine that regulates glucose homeostasis by promoting glucose production and liver insulin resistance in mouse models. FABP4 levels are increased in GDM and correlates with maternal indices of insulin resistance, with a rapid decline post-partum. We therefore aimed to determine the tissue origin of elevated circulating FABP4 levels in GDM and to assess its potential contribution in promoting glucagon-induced hepatic glucose production., Materials and Methods: FABP4 protein and gene expression was determined in biopsies from placenta, subcutaneous (sWAT) and visceral (vWAT) white adipose tissues from GDM and normoglycaemic pregnant women. FABP4 differential contribution in glucagon-stimulated hepatic glucose production was tested in conditioned media before and after its immune clearance., Results: We showed that FABP4 is expressed in placenta, sWAT and vWAT of pregnant women at term, with a significant increase in its secretion from vWAT of women with GDM compared with normoglycaemic pregnant women. Neutralizing FABP4 from both normoglycaemic pregnant women and GDM vWAT secretome, resulted in a decrease in glucagon-stimulated hepatic glucose production., Conclusions: This study provides new insights into the role of adipose tissue-derived FABP4 in GDM, highlighting this adipokine, as a potential co-activator of glucagon-stimulated hepatic glucose production during pregnancy., (© 2023 The Authors. Diabetes, Obesity and Metabolism published by John Wiley & Sons Ltd.)

Spinal anesthesia (SA) is gaining recognition as a safe and efficacious regional alternative to general anesthesia for elective lumbar surgery. However, unfamiliarity with management issues related to its use has limited the adoption of awake spine surgery, despite its benefits. Few centers in the United States routinely offer SA for elective lumbar surgery, and a comprehensive workflow to standardize SA for lumbar surgery is lacking. In this article, we examine recent literature on the use of SA in lumbar surgery, review the experience of our institution with SA in lumbar surgery, and provide a cohesive outline to streamline the implementation of SA from the perspective of the anesthesiologist. We review the critical features of SA in contemporary lumbar surgery, including selection of patients, methods of SA, intraoperative sedation, and management of several important technical considerations. We aimed to flatten the learning curve to improve the availability and accessibility of the technique for eligible patients.

Introduction: An increasing number of jurisdictions have legalized recreational cannabis for adult use. The subsequent availability and marketing of recreational cannabis has led to a parallel increase in rates and severity of pediatric cannabis intoxications. We explored predictors of severe outcomes in pediatric patients who presented to the emergency department with cannabis intoxication., Methods: In this prospective cohort study, we collected data on all pediatric patients (<18 years) who presented with cannabis intoxication from August 2017 through June 2020 to participating sites in the Toxicology Investigators Consortium. In cases that involved polysubstance exposure, patients were included if cannabis was a significant contributing agent. The primary outcome was a composite severe outcome endpoint, defined as an intensive care unit admission or in-hospital death. Covariates included relevant sociodemographic and exposure characteristics., Results: One hundred and thirty-eight pediatric patients (54% males, median age 14.0 years, interquartile range 3.7-16.0) presented to a participating emergency department with cannabis intoxication. Fifty-two patients (38%) were admitted to an intensive care unit, including one patient who died. In the multivariable logistic regression analysis, polysubstance ingestion (adjusted odds ratio = 16.3; 95% confidence interval: 4.6-58.3; P  < 0.001)) and cannabis edibles ingestion (adjusted odds ratio = 5.5; 95% confidence interval: 1.9-15.9; P  = 0.001) were strong independent predictors of severe outcome. In an age-stratified regression analysis, in children older than >10 years, only polysubstance abuse remained an independent predictor for the severe outcome (adjusted odds ratio 37.1; 95% confidence interval: 6.2-221.2; P  < 0.001). As all children 10 years and younger ingested edibles, a dedicated multivariable analysis could not be performed (unadjusted odds ratio 3.3; 95% confidence interval: 1.6-6.7)., Conclusions: Severe outcomes occurred for different reasons and were largely associated with the patient's age. Young children, all of whom were exposed to edibles, were at higher risk of severe outcomes. Teenagers with severe outcomes were frequently involved in polysubstance exposure, while psychosocial factors may have played a role.

Spinal stenosis is one of the most common neurosurgical diseases and a leading cause of pain and disability. Wild-type transthyretin amyloid (ATTRwt) has been found in the ligamentum flavum (LF) of a significant subset of patients with spinal stenosis who undergo decompression surgery. Histologic and biochemical analyses of LF specimens from spinal stenosis patients, normally discarded as waste, have the potential to help elucidate the underlying pathophysiology of spinal stenosis and possibly allow for medical treatment of stenosis and screening for other systemic diseases. In the present review, we discuss the utility of analyzing LF specimens after spinal stenosis surgery for ATTRwt deposits. Screening for ATTRwt amyloidosis cardiomyopathy through LF specimens has led to the early diagnosis and treatment of cardiac amyloidosis in several patients, with more expected to benefit from this process. Emerging evidence in the literature also point to ATTRwt as a contributor to a previously unrecognized subtype of spinal stenosis in patients who might, in the future, benefit from medical therapy. In the present report, we review the current literature regarding the early detection of ATTRwt cardiomyopathy via LF screening and the possible contribution of ATTRwt deposits in the LF to spinal stenosis development., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Background: Spinal anesthesia is an effective modality for lumbar surgery. Patient eligibility with respect to medical comorbidities remains a topic of debate. Obesity (body mass index ≥30 kg/m 2 ), anxiety, obstructive sleep apnea, reoperation at the same level, and multilevel operations have variously been reported as relative contraindications. We hypothesize that patients undergoing common lumbar surgeries with these comorbidities do not experience greater rates of complications compared with controls., Methods: We analyzed a prospectively collected database of patients undergoing thoracolumbar surgery under spinal anesthesia and identified 422 cases. Surgeries were less than 3 hours (the duration of action of intrathecal bupivacaine) and include microdiscectomies, laminectomies, and both single-level and multilevel fusions. Procedures were performed by a single surgeon at a single academic center. In overlapping groups, 149 patients had a body mass index ≥30 kg/m 2 , 95 had diagnosed anxiety, 79 underwent multilevel surgery, 98 had obstructive sleep apnea, and 65 had a previous operation at the same level. The control group included 132 patients who did not have these risk factors. Differences in important perioperative outcomes were assessed., Results: There were no statistically significant differences in intraoperative and postoperative complications except 2 cases of pneumonia in the anxiety group and 1 case in the reoperative group. There were also no significant differences for patients with multiple risk factors. Rates of spinal fusion were similar among groups, although mean length of stay and operative time were different., Conclusions: Spinal anesthesia is a safe option for patients with significant comorbidities and can be considered for most patients undergoing routine lumbar surgeries., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Background: Triggered electromyography (tEMG) is an intraoperative neuromonitoring technique used to assess pedicle screw placement during instrumented fusion procedures. Although spinal anesthesia is a safe alternative to general anesthesia in patients undergoing lumbar fusion, its use may potentially block conduction of triggered action potentials or may require higher threshold currents to elicit myotomal responses when using tEMG. Given the broad utilization of tEMG for confirmation of pedicle screw placement, adoption of spinal anesthesia may be hindered by limited studies of its use alongside tEMG., Objective: To investigate whether spinal anesthesia affects the efficacy of tEMG, we compare the baseline spinal nerve thresholds during lumbar fusion procedures under general vs spinal anesthesia., Methods: Twenty-three consecutive patients (12 general and 11 spinal) undergoing single-level transforaminal lumbar interbody fusion were included in the study. Baseline nerve threshold was determined through direct stimulation of the spinal nerve using tEMG., Results: Baseline spinal nerve threshold did not differ between the general and spinal anesthesia cohorts (3.25 ± 1.14 vs 3.64 ± 2.16 mA, respectively; P = .949). General and spinal anesthesia cohorts did not differ by age, body mass index, American Society of Anesthesiologists score status, or surgical indication., Conclusion: We report that tEMG for pedicle screw placement can be safely and effectively used in procedures under spinal anesthesia. The baseline nerve threshold required to illicit a myotomal response did not differ between patients under general or spinal anesthesia. This preliminary finding suggests that spinal anesthetic blockade does not contraindicate the use of tEMG for neuromonitoring during pedicle screw placement., (Copyright © Congress of Neurological Surgeons 2023. All rights reserved.)

Background: Transmetatarsal amputation (TMA) is a well-recognized limb-salvage procedure, often indicated for the treatment of diabetic foot infections. Currently, there is no widespread agreement in the literature with regard to the factors associated with failure of TMA. This study aimed to define risk factors for the failure of TMA, defined as below-the-knee or above-the-knee amputation, in patients with diabetes., Methods: This retrospective cohort study included 341 patients who underwent primary TMA. Patients who had a revision to a higher level (the failed TMA group) were compared with those who did not have failure of the initial amputation (the successful TMA group)., Results: This study showed a higher frequency of renal impairment, defined as a high creatinine level and/or a previous kidney transplant or need for dialysis, in the failed TMA group (p = 0.002 for both). Furthermore, a Charlson Comorbidity Index (CCI) threshold value of 7.5 was identified as the optimal predictive value for failure of TMA (p = 0.002), and patients with a CCI of >7.5 had a median time of 1.13 months until the initial amputation failed., Conclusions: TMA is associated with a high risk of revision. CCI may be used as a preoperative selection criterion, as 71.8% of patients with a CCI of >7.5 had failure of the TMA., Level of Evidence: Therapeutic Level III . See Instructions for Authors for a complete description of levels of evidence., Competing Interests: Disclosure: The Disclosure of Potential Conflicts of Interest forms are provided with the online version of the article ( http://links.lww.com/JBJS/H456 )., (Copyright © 2023 by The Journal of Bone and Joint Surgery, Incorporated.)

Background: Spinal anesthesia (SA) is a safe and effective alternative to general endotracheal anesthesia (GEA) for lumbar surgery. Foremost among the reasons to avoid GEA is the desire to minimize postoperative cognitive dysfunction (POCD). Although POCD is a complex and multifactorial entity, the risk of its development has been associated with anesthetic modality and perioperative polypharmacy, among others., Objective: To determine whether SA reduced polypharmacy compared with GEA in patients undergoing transforaminal lumbar interbody fusion (TLIF)., Methods: Demographic and procedural data of 424 consecutive TLIF patients were extracted retrospectively. Patients undergoing single-level TLIF through GEA (n = 186) or SA (n = 238) were enrolled into our database. Perioperative medications, excluding antibiotic prophylaxis and local anesthetics, were classified into various categories., Results: Patients in the SA cohort received a mean of 4.5 medications vs a mean of 10.5 medications in the GEA cohort ( P < .0001). This reduction in perioperative medications remained significant after a multivariate analysis to control for confounders ( P < .001 for all variables). The use of vasopressors was significantly reduced in the SA cohort ( P < .001), which coincided with a significant reduction in hypotensive episodes ( P < .001). Patients undergoing TLIF through GEA had 3.6 times greater odds of experiencing a hypotensive episode intraoperatively (odds ratio = 3.62, 95% CI [2.38-5.49])., Conclusion: Spinal anesthesia is associated with a significant decrease in perioperative medications and may confer superior intraoperative hemodynamic stability, which lowers pressor requirements. The decrease of perioperative medications may be an important contribution in reducing the incidence of POCD in patients undergoing TLIFs, although this requires further study., (Copyright © Congress of Neurological Surgeons 2022. All rights reserved.)

Background: Spinal anesthesia is safe and effective in lumbar surgeries, with numerous advantages over general anesthesia (GA). Nevertheless, 1 major concern preventing the widespread adoption of this anesthetic modality in spine surgeries is the potential for intraprocedural anesthetic failure, resulting in the need to convert to GA intraoperatively., Objective: To present a novel additional prone dose algorithm for when a first spinal dose fails to achieve the necessary effect., Methods: A total of 422 consecutive patients undergoing simple and complex thoracolumbar surgeries under spinal anesthesia were prospectively enrolled into our database. Data were retrospectively collected through extraction of electronic health records., Results: Sixteen of 422 required a second prone dose, of whom 1 refused and was converted to GA preoperatively. After 15 were given a prone dose, only 2 required preoperative conversion to GA. There were no instances of intraoperative conversion to GA. The success rate for spinal anesthesia without the need for conversion rose from 96.4% to 99.5%. In patients who required a second prone dose, there were no instances of spinal headache, deep vein thrombosis, pneumonia, urinary tract infection, urinary retention, readmission within 30 days, acute pain service consult, return to operating room, durotomy, or cerebrospinal fluid on puncture., Conclusion: Use of an additional prone dose algorithm was able to achieve a 99.5% success rate, and those who received this second dose did not experience any complications or negative operative disadvantages. Further research is needed to investigate which patients are at increased risk of inadequate analgesia with spinal anesthesia., (Copyright © Congress of Neurological Surgeons 2023. All rights reserved.)

Background: Postoperative pain is a barrier to early mobility and discharge after lumbar surgery. Liposomal bupivacaine (LB) has been shown to decrease postoperative pain and narcotic consumption after transforaminal lumbar interbody fusions (TLIFs) when injected into the marginal suprafascial/subfascial plane-liposomal bupivacaine (MSSP-LB). Erector spinae plane (ESP) infiltration is a relatively new analgesic technique that may offer additional benefits when performed in addition to MSSP-LB., Objective: To evaluate postoperative outcomes of combining ESP-LB with MSSP-LB compared with MSSP-LB alone after single-level TLIF., Methods: A retrospective analysis was performed for patients undergoing single-level TLIFs under spinal anesthesia, 25 receiving combined ESP-LB and MSSP-LB and 25 receiving MSSP-LB alone. The primary outcome was length of hospitalization. Secondary outcomes included postoperative pain score, time to ambulation, and narcotics usage., Results: Baseline demographics and length of surgery were similar between groups. Hospitalization was significantly decreased in the ESP-LB + MSSP-LB cohort (2.56 days vs 3.36 days, P = .007), as were days to ambulation (0.96 days vs 1.29 days, P = .026). Postoperative pain area under the curve was significantly decreased for ESP-LB + MSSP-LB at 12 to 24 hours (39.37 ± 21.02 vs 53.38 ± 22.11, P = .03) and total (44.46 ± 19.89 vs 50.51 ± 22.15, P = .025). Postoperative narcotic use was significantly less in the ESP-LB + MSSP-LB group at 12 to 24 hours (13.18 ± 4.65 vs 14.78 ± 4.44, P = .03) and for total hospitalization (137.3 ± 96.3 vs 194.7 ± 110.2, P = .04)., Conclusion: Combining ESP-LB with MSSP-LB is superior to MSSP-LB alone for single-level TLIFs in decreasing length of hospital stay, time to ambulation, postoperative pain, and narcotic use., (Copyright © Congress of Neurological Surgeons 2022. All rights reserved.)

Chemical analysis of hazardous surface contaminations, such as hazardous substances, explosives or illicit drugs, is an essential task in security, environmental and safety applications. This task is mostly based on the collection of particles with swabs, followed by thermal desorption into a vapor analyzer, usually a detector based on ion mobility spectrometry (IMS). While this methodology is well established for several civil applications, such as border control, it is still not efficient enough for various conditions, as in sampling rough and porous surfaces. Additionally, the process of thermal desorption is energetically inefficient, requires bulky hardware and introduces device contamination memory effects. Low-temperature plasma (LTP) has been demonstrated as an ionization and desorption source for sample preparation-free analysis, mostly at the inlet of a mass spectrometer analyzer, and in rare cases in conjunction with an ion mobility spectrometer. Herein, we demonstrate, for the first time, the operation of a simple, low cost, home-built LTP apparatus for desorbing non-volatile analytes from various porous surfaces into the inlet of a handheld IMS vapor analyzer. We show ion mobility spectra that originate from operating the LTP jet on porous surfaces such as asphalt and shoes, contaminated with model amine-containing organic compounds. The spectra are in good correlation with spectra measured for thermally desorbed species. We verify through LC-MS analysis of the collected vapors that the sampled species are not fragmented, and can thus be identified by commercial IMS detectors.

Objective: Intracranial hemorrhage (ICH) in patients with left ventricular assist devices (LVAD) is a devastating complication. Demographic risk factors for ICH in LVAD patients are defined, however anatomic predispositions to ICH are unknown. We sought to interrogate intracranial radiographic risk factors for ICH in LVAD patients., Methods: We reviewed 440 patients who received an LVAD from 2008-2021. We selected patients with CT scans of the head either before or after LVAD placement, but typically within 5 years. 288 patients (21 ICH, 267 Control) with imaging were included. A detailed chart review was performed on demographics, radiographic features, and management., Results: The incidence of ICH in our total cohort was 8.6% (38/440). The presence of pump thrombosis (p=0.001), driveline infection (p=0.034), other hemorrhage (p=0.001), or previous placement of a cardio-defibrillator (p=.003) was associated with increased risk for ICH. An analysis of imaging revealed that the presence of a mass (p=0.006), vascular pathology (p=0.001), and microangiopathy (p=0.04) was significantly associated with ICH in LVAD patients. These radiographic features were validated with a multivariate logistic regression which confirmed presence of a mass (aOR 332.1, 95% CI: 14.7-7485.1, p<0.001), vascular pathology (aOR 69.7, 95% CI: 1.8-2658.8, p=0.022), and microangiopathy (aOR 6.5, 95% CI: 1.1-37.6, p=0.035) were independently associated with ICH., Conclusion: Radiographic evidence of microangiopathy, intracranial mass, and vascular pathology are independent risk factors for ICH which are readily identified by imaging. We advocate that CT imaging be used to further stratify patients at highest risk of ICH during treatment with an LVAD., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Background: Lumbar spinal stenosis (LSS) is a common reason for spine surgery in which ligamentum flavum is resected. Transthyretin (TTR) amyloid is an often unrecognized and potentially modifiable mechanism for LSS that can also cause TTR cardiac amyloidosis. Accordingly, older adult patients undergoing lumbar spine (LS) surgery were evaluated for amyloid and if present, the precursor protein, as well as comprehensive characterization of the clinical phenotype., Methods: A prospective, cohort study in 2 academic medical centers enrolled 47 subjects (age 69 ± 7 years, 53% male) undergoing clinically indicated LS decompression. The presence of amyloid was evaluated by Congo Red staining and in those with amyloid, precursor protein was determined by laser capture microdissection coupled to mass spectrometry (LCM-MS). The phenotype was assessed by disease-specific questionnaires (Swiss Spinal Stenosis Questionnaire and Kansas City Cardiomyopathy Questionnaire) and the 36-question short-form health survey, as well as biochemical measures (TTR, retinol-binding protein, and TTR stability). Cardiac testing included technetium-99m-pyrophosphate scintigraphy, electrocardiograms, echocardiograms, and cardiac biomarkers as well as measures of functional capacity., Results: Amyloid was detected in 16 samples (34% of participants) and was more common in those aged ≥ 75 years of age (66.7%) compared with those <75 years (22.3%, p < 0.05). LCM-MS demonstrated TTR as the precursor protein in 62.5% of participants with amyloid while 37.5% had an indeterminant type of amyloid. Demographic, clinical, quality-of-life measures, electrocardiographic, echocardiographic, and biochemical measures did not differ between those with and without amyloid. Among those with TTR amyloid (n = 10), one subject had cardiac involvement by scintigraphy., Conclusions: Amyloid is detected in more than a third of older adults undergoing LSS. Amyloid is more common with advancing age and is particularly common in those >75 years old. No demographic, clinical, biochemical, or cardiac parameter distinguished those with and without amyloid. In more than half of subjects with LS amyloid, the precursor protein was TTR indicating the importance of pathological assessment., (© 2022 The American Geriatrics Society.)

Objective: Postoperative urinary retention (POUR) is a common and vexing complication in elective spine surgery. Efficacious prevention strategies are still lacking, and existing studies focus primarily on identifying risk factors. Spinal anesthesia has become an attractive alternative to general anesthesia in elective lumbar surgery, with the potential of having a differential impact on POUR., Methods: 422 spinal anesthesia procedures were prospectively collected between 2017 and 2021 and compared to 416 general anesthesia procedures retrospectively collected between 2014 and 2017, at a single academic center by the same senior neurosurgeon. The main outcome was POUR, defined as the need for straight bladder catheterization or indwelling bladder catheter placement after surgery due to failure to void. A power calculation was performed prior to data collection., Results: The general anesthesia group had a higher rate of POUR (9.1 %) compared with the spinal anesthesia group (4.3 %), p = 0.005. At baseline, the spinal anesthesia cohort had an older average age and fewer patients with a history of previous spine surgery. Other comorbid conditions were comparable between the groups. For perioperative characteristics, spinal anesthesia patients had higher ASA scores, shorter operative times, shorter lengths of hospital stay, less operative levels, and zero use of intraoperative bladder catheterization. Acute pain service consult was similar between the groups. A multivariable logistic regression revealed that spinal anesthesia was associated with a significantly lower rate of urinary retention in the spinal anesthesia group (p = 0.0130), after adjusting for potentially confounding factors. Other statistically significant risk factors for POUR included diabetes, (p = 0.003), BPH (p = 0.014), operative time (p = 4.94e-06), and ASA score (p = 0.005)., Conclusions: We collect and analyze one of the largest available cohorts of patients undergoing simple and complex surgeries under spinal and general anesthesia, finding that spinal anesthesia is independently associated with a lower incidence of POUR compared to general anesthesia, even when adjusted for potentially confounding risk factors. Further prospective trials are needed to explore this finding., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Dr. Arnold Max Meirowsky (1910-1984) was enormously influential to military neurosurgery during the Korean War, introducing to the American military the concept of the mobile neurosurgical unit. After implementation of the neurosurgical detachment, meningocerebral infections saw a decrease from 41% to less than 1%, with similar improvements in mortality and complication rates. Additionally, Meirowsky developed many techniques and improvements in neurosurgery, specifically in the field of neurosurgical trauma, which he dedicated himself to even after reentering civilian practice. Furthermore, his mentorship of Korean surgeons and the influence of his mobile neurosurgical unit were major influences cited to be pivotal to the founding of neurosurgery as a specialty in South Korea. As he is underrecognized for these accomplishments in the neurosurgical literature, the authors seek to review his wartime and career contributions. They also specifically present details of his standardization of the mobile neurosurgical unit and showcase several of his other advancements in the treatment of neurosurgical trauma.

Objective: Nonoperative management of odontoid fractures can result in solid fusion, unstable nonunion, and fibrous nonunion. Odontoid fractures with fibrous nonunion will not demonstrate dynamic instability on imaging studies. However, the safety of accepting this outcome has been debated. We have provided, to the best of our knowledge, the first systematic review of the existing literature to explore the safety of allowing fibrous nonunion as an acceptable outcome for odontoid fractures., Methods: The PubMed and Embase databases were searched in January 2022. The outcomes were extracted and categorized according to the mortality, neurologic sequelae, pain, neck disability index, and satisfaction., Results: Of a total of 700 abstracts screened, the full text of 79 reports was assessed, with 13 studies included. Of the included patients, 141 had had a fibrous nonunion, all described in observational studies. The follow-up ranged from 0.6 to 5.8 years. None of the 141 patients had experienced a neurologic event. One patient had died of trauma-related issues; however, causality was not reported. Most of the studies had reported good to excellent pain scores. Most of the neck disabilities reported had ranged from mild to moderate in severity. However, 1 study of 5 patients had reported severe disability. All the patients reported good or excellent satisfaction., Conclusions: The evidence we found supports that it is safe to forgo surgery for carefully selected patients with nonunited odontoid fractures when near-anatomic alignment is present, dynamic instability is lacking on imaging studies, the neurologic examination findings are normal, and the risk of neck injury is low. Further study is needed to define the full natural history of fibrous nonunion of odontoid fractures., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Objective: The extreme elderly population (≥80 years of age) is expected to triple globally by 2050 and surgeries in this age group are likely to increase. Spinal anesthesia has emerged as a safe and effective alternative to general anesthesia in lumbar surgery and may particularly benefit extreme elderly patients concerned with post-operative cognitive dysfunction, poor physiological reserves, and polypharmacy. However, literature supporting its use in this population is lacking and there are potential challenges such as degenerative anatomy and medical comorbidities. Here, we assess the safety and feasibility of using spinal anesthesia in the extreme elderly., Methods: Between 2017 and 2021, 424 consecutive lower thoracic and lumbar spine surgeries were performed under spinal anesthesia by a single surgeon at a large academic hospital and procedural details were collected in a prospective database. Forty-six patients were ≥ 80 years in age. Demographic, surgical, perioperative, and anesthetic data were retrospectively analyzed., Results: The extreme elderly cohort had increased ASA scores, levels of surgery, and length of stay. Similar rates occurred for spinal headache, deep vein thrombosis, pneumonia, urinary tract infection, urinary retention, readmission within 30 days, acute pain service consult, return to the operating room, and durotomy. Intraoperative visualization of the spinal anesthesia dural puncture was increased in the extreme elderly (3 vs. 1 patient)., Conclusion: We report one of the largest series of extreme elderly patients undergoing spinal anesthesia for simple and complex lumbar spine surgeries and demonstrate that spinal anesthesia can be safe and feasible in this population., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Background: One key contributor to lumbar stenosis is thickening of the ligamentum flavum (LF), a process still poorly understood. Wild-type transthyretin amyloid (ATTRwt) has been found in the LF of patients undergoing decompression surgery, suggesting that amyloid may play a role. However, it is unclear whether within patients harboring ATTRwt, the amount of amyloid is associated with LF thickness., Methods: From an initial cohort of 324 consecutive lumbar stenosis patients whose LF specimens from decompression surgery were sent for analysis (2018-2019), 33 patients met the following criteria: 1) Congo red-positive amyloid in the LF, 2) ATTRwt by mass spectrometry-based proteomics, and 3) an available preoperative magnetic resonance imaging. Histological specimens were digitized, and amyloid load was quantified through Trainable Weka Segmentation machine learning. LF thicknesses were manually measured on axial T2-weighted preoperative magnetic resonance imaging scans at each lumbar level, L1-S1. The sum of thicknesses at every lumbar LF level (L1-S1) equals "lumbar LF burden"., Results: Patients had a mean age of 72.7 years (range = 59-87), were mostly male (61%) and white (82%), and predominantly had surgery at L4-L5 levels (73%). Amyloid load was positively correlated with LF thickness (R = 0.345, P = 0.0492) at the levels of surgical decompression. Furthermore, amyloid load was positively correlated with lumbar LF burden (R = 0.383, P = 0.0279)., Conclusions: Amyloid load is positively correlated with LF thickness and lumbar LF burden across all lumbar levels, in a dose-dependent manner. Further studies are needed to validate these findings, uncover the underlying pathophysiology, and pave the way toward using therapies that slow LF thickening., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Background: The U.S. health care sector produces approximately 10% of national greenhouse gas emissions, paradoxically harming human health. Neurosurgery is a resource-intensive specialty that likely contributes significantly, yet literature assessing this impact is absent. We investigate the difference in carbon emissions between spinal versus general anesthesia in lumbar spine surgery., Methods: A total of 100 patients underwent a single-level transforaminal lumbar interbody fusion (TLIF) from a single surgeon; 50 received spinal anesthesia and 50 received general anesthesia. Data were extracted from patient records. Amounts of anesthetics were calculated from intraoperative records and converted to carbon dioxide equivalents (CO 2 e)., Results: The median CO 2 e for general anesthesia was 4725 g versus 70 g for spinal anesthesia (P = 7.07e-18). The mean CO 2 e for general anesthesia was 22,707 g versus 63 g for spinal anesthesia. Desflurane use led to outsized carbon emissions. Carbon footprint comparisons are made with familiar units such as miles driven by a car, and are provided for a single TLIF, 50 TLIFs (single surgeon's cases in a year), and 488,000 TLIFs (annual spinal fusions in the United States)., Conclusion: This is one of the first known comparative carbon footprint studies performed in neurosurgical literature. We highlight the dramatic carbon footprint reduction associated with using spinal anesthesia and reflect a single neurosurgeon's change in practice from using only general anesthesia to incorporating the use of spinal anesthesia. Within general anesthesia patients, desflurane use was particularly harmful to the environment. We hope that our study will pave the way toward future research aimed at uncovering and reducing neurosurgery's environmental impact., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Objective: Wild-type transthyretin amyloid (ATTRwt) is deposited in the ligamentum flavum (LF) of a subset of patients with spinal stenosis who undergo decompressive surgery, although its role in the pathophysiology of spinal stenosis is unknown. It has been theorized that degeneration of intervertebral discs causes increased mechanical stress and inflammatory/degenerative cascades and ultimately leads to LF fibrosis. If ATTRwt deposits contribute to LF thickening and spinal stenosis through a different pathway, then patients with ATTRwt may have less severe disc degeneration than those without it. In this study, the authors compared the severity of disc degeneration between patients with lumbar stenosis with and without amyloid in their LF to test whether ATTRwt is a unique contributor to LF thickening and spinal stenosis., Methods: Of 324 consecutive patients between 2018 and 2019 who underwent decompression surgery for spinal stenosis and had LF samples sent for pathological analysis, 31 harboring ATTRwt were compared with 88 controls. Patient medical records were retrospectively reviewed for demographic and surgical information. Disc degeneration was assessed on preoperative T2-weighted MR images with the modified Pfirrmann grading system at every lumbar disc level., Results: Baseline characteristics were similar between the groups, except for a statistically significant increase in age in the ATTRwt group. The crude unadjusted comparisons between the groups trended toward a less severe disc degeneration in the ATTRwt group, although this difference was not statistically significant. A multivariable linear mixed-effects model was created to adjust for the effects of age and to isolate the influence of ATTRwt, the presence of an operation at the level, and the specific disc level (between L1 and S1). This model revealed that ATTRwt, the presence of an operation, and the specific level each had significant effects on modified Pfirrmann scores., Conclusions: Less severe disc degeneration was noted in patients with degenerative spinal stenosis harboring ATTRwt compared with those without amyloid. This finding suggests that ATTRwt deposition may play a separate role in LF thickening from that played by disc degeneration. Future studies should aim to elucidate this potentially novel pathophysiological pathway, which may uncover an exciting potential for the development of amyloid-targeted therapies that may help slow the development of spinal stenosis.

The New England Neurosurgical Society (NENS) was founded in 1951 under the leadership of its first President (Dr. William Beecher Scoville) and Secretary-Treasurer (Dr. Henry Thomas Ballantine). The purpose of creating the NENS was to unite local neurosurgeons in the New England area; it was one of the first regional neurosurgical societies in America. Although regional neurosurgical societies are important supplements to national organizations, they have often been overshadowed in the available literature. Now in its 70th year, the NENS continues to serve as a platform to represent the needs of New England neurosurgeons, foster connections and networks with colleagues, and provide research and educational opportunities for trainees. Additionally, regional societies enable discussion of issues uniquely relevant to the region, improve referral patterns, and allow for easier attendance with geographic proximity. In this paper, the authors describe the history of the NENS and provide a roadmap for its future. The first section portrays the founders who led the first meetings and establishment of the NENS. The second section describes the early years of the NENS and profiles key leaders. The third section discusses subsequent neurosurgeons who steered the NENS and partnerships with other societies. In the fourth section, the modern era of the NENS and its current activities are highlighted.

The datasets presented here quantify and compare the relative carbon footprints emitted by general versus spinal anesthesia in patients undergoing single-level transforaminal lumbar interbody fusions (TLIFs). Data were retrospectively collected from electronic medical records of 100 consecutive patients who underwent a single-level TLIF from a single neurosurgeon at a U.S. academic center. 50 patients were under general anesthesia, and another 50 patients were under spinal anesthesia. Clinic and operative notes were used to extract demographic and surgical information, whereas anesthesia records were used to extract anesthetic information. Using the anesthetic information, carbon dioxide equivalents (CO 2 e) were calculated for each type of anesthetic and summed together to compute the total carbon footprint for each patient. Our article entitled "Assessing the environmental carbon footprint of spinal versus general anesthesia in single-level transforaminal lumbar interbody fusions" is based on this data [1]. Raw datasets of the primary data collection as well as cleaned and analyzed datasets are presented. These datasets highlight the first known environmental impact calculation from medical records of a spine procedure, serving as a model for other interested investigators to explore and emulate. This data brief may help to pave the way towards future environmental research and practice changes within neurosurgical and orthopedic literature, an issue critical to the sustainability of our modern society., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2022 The Author(s). Published by Elsevier Inc.)

Background: Spinal anesthesia is a safe and effective alternative to general anesthesia in both simple and complex lumbar surgery with numerous reported advantages leading to increased recent utilization. One potential barrier to the use of spinal anesthesia in lumbar surgery is the popularity of intraoperative computed tomography (CT) imaging. Intraoperative CT necessitates motionless patients and adds time to procedures, issues that may make surgeons hesitant to use concomitant spinal anesthesia. To date, the use of both techniques simultaneously has not been well described., Objective: We propose that single-level lumbar fusions utilizing intraoperative CT scan acquisition and navigated instrumentation are feasible under single-dose spinal anesthesia without detrimental effect on image quality and navigation accuracy or need for spinal anesthetic re-dosing due to the additional time necessary., Methods: We describe operative characteristics and intra-operative timing for our first five cases of transforaminal lumbar interbody fusion (TLIF) completed with intraoperative CT scan acquisition and navigated instrumentation performed under spinal anesthesia., Results: The five patients ranged in age from 59 to 79 years, with an average body mass index of 27.0 kg/m 2 . The average total operative time for each surgery 109.2 min, including approximately 6.3 min required for CT scan acquisition. There were no complications and post-operative imaging demonstrated no malpositioned pedicle screws., Conclusion: Single-level TLIF procedures utilizing intraoperative CT acquisition and navigated instrumentation can be feasibly completed under single-dose spinal anesthesia without need for intraoperative apneic periods and without deleterious effect on instrumentation accuracy., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Biologically-modified field-effect transistors (BioFETs) are promising platforms for specific and label-free biosensing due to their sub-micron footprint suitable for multiplexing in ultra-small samples, low noise levels, inherent amplification, etc . Debye screening length is a well-recognized challenge for any BioFET-based technology. The screening length is the smallest at the double layer, where the solution ion population is higher than the bulk population. One way to address the small double layer screening length is to electrostatically modify the potential drop across the solution such as to minimize the potential drop over the double layer. This will decrease the population of the double layer ions and increase the screening length. However, this is not possible with BioFETs as voltage application to the reference electrode simultaneously affects both the double layer and the BioFET conducting channel. The current study addresses the screening length challenge with the novel Meta-Nano-Channel (MNC) BioFET. The MNC BioFET, which is fabricated in a complementary-metal-oxide-silicon (CMOS) process, allows decoupling of the electrostatics of the double layer from the electrodynamics of the conducting channel. The study explores the mechanism of sensing with the MNC BioFET, and demonstrates how the double layer can be electrostatically tuned in order to optimize the screening length without affecting the conducting channel. Finally, specific and label-free sensing of 10 ng ml -1 prostate specific antigen (PSA) is demonstrated. It is shown that by electrostatically increasing the double layer screening length, the sensing signal increases from 70 mV to 133 mV.

Wild-type transthyretin amyloidosis (ATTRwt) is an underdiagnosed and potentially fatal disease. Interestingly, ATTRwt deposits have been found to deposit in the ligamentum flavum (LF) of patients with lumbar spinal stenosis before the development of systemic and cardiac amyloidosis. In order to study this phenomenon and its possible relationship with LF thickening and systemic amyloidosis, a precise method of quantifying amyloid deposits in histological slides of LF is critical. However, such a method is currently unavailable. Here, we present a machine learning quantification method with Trainable Weka Segmentation (TWS) to assess amyloid deposition in histological slides of LF. Images of ligamentum flavum specimens stained with Congo red are obtained from spinal stenosis patients undergoing laminectomies and confirmed to be positive for ATTRwt. Amyloid deposits in these specimens are classified and quantified by TWS through training the algorithm via user-directed annotations on images of LF. TWS can also be automated through exposure to a set of training images with user-directed annotations, and then applied] to a set of new images without additional annotations. Additional methods of color thresholding and manual segmentation are also used on these images for comparison to TWS. We develop the use of TWS in images of LF and demonstrate its potential for automated quantification. TWS is strongly correlated with manual segmentation in the training set of images with user-directed annotations (R = 0.98; p = 0.0033) as well as in the application set of images where TWS was automated (R = 0.94; p = 0.016). Color thresholding was weakly correlated with manual segmentation in the training set of images (R = 0.78; p = 0.12) and in the application set of images (R = 0.65; p = 0.23). TWS machine learning closely correlates with the gold-standard comparator of manual segmentation and outperforms the color thresholding method. This novel machine learning method to quantify amyloid deposition in histological slides of ligamentum flavum is a precise, objective, accessible, high throughput, and powerful tool that will hopefully pave the way towards future research and clinical applications., Competing Interests: All authors report no conflict of interest., (© 2022 The Authors.)

The blennies, Acanthemblemaria spinosa (Chaenopsidae) and Enneanectes altivelis (Tripterygiidae) are representative members of two families spanning the deepest node of the Blennioidei tree. The mitogenomes of 16,507 bp for A. spinosa and 16,529 bp for E. altivelis each consisted of 37 genes and one control loop region. Phylogenetic analysis confirmed the placement of Chaenopsidae and Tripterygiidae within the Blenniiformes, however, there was instability in the placement of the triplefins between reconstruction methods, likely due to low taxon sampling. These mitogenomes represent an important milestone in uncovering relationships within Blenniiformes and Ovalentaria., Competing Interests: The authors have no potential conflicts of interest., (© 2022 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.)

Objective: Post-operative quadriparesis following posterior cervical decompression and fusion is a rare but devastating complication. Unless rapidly identified and treated, it can cause permanent injury and disability. Given the sparse literature on this topic we intend to report on its incidence, to identify potential predisposing risk factors, and to discuss management considerations., Methods: We retrospectively reviewed a series of 301 patients who underwent posterior cervical decompressive laminectomies and instrumented fusion performed by the senior author between 2006 and 2020. We describe the clinical courses and interventions for the seven of these 301 patients who developed post-operative quadriparesis., Results: The incidence of post-operative quadriparesis following cervical spine decompressive laminectomies and instrumented fusion was 2.3% (7/301) in our study. The mean time-to-onset was 2 days, and the most common pathology was post-operative hematoma. We did not identify any statistically significant risk factors that predispose patients to post-operative quadriparesis. In our series, the patients with post-operative quadriparesis without profound hypotension who underwent emergent surgical decompression demonstrated improved neurologic outcomes compared to those who underwent interval imaging prior to decompression., Conclusion: Post-operative quadriparesis following cervical spine surgery is a catastrophic complication that is poorly reported and under-studied in current literature. In this study, we found a 2.3% incidence of post-operative quadriparesis with no obvious risk factors predisposing patients to this adverse outcome. We advocate that post-operative quadriparesis following cervical spine surgery, in the absence of profound hypotension, warrants emergent surgical site exploration without delay for interval imaging., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Aims/hypothesis: Fatty acid-binding protein 4 (FABP4) is an adipokine with a key regulatory role in glucose and lipid metabolism. We prospectively evaluated the role of FABP4 in the pathophysiology of diabetic ketoacidosis (DKA) in new-onset type 1 diabetes., Methods: Clinical and laboratory data were prospectively collected from consecutive children presenting with new-onset type 1 diabetes. In addition to blood chemistry and gases, insulin, C-peptide, serum FABP4 and NEFA were collected upon presentation and 48 h after initiation of insulin treatment. In a mouse model of type 1 diabetes, glucose, insulin, β-hydroxybutyrate and weight were compared between FABP4 knockout (Fabp4 -/- ) and wild-type (WT) mice., Results: Included were 33 children (mean age 9.3 ± 3.5 years, 52% male), of whom 14 (42%) presented with DKA. FABP4 levels were higher in the DKA group compared with the non-DKA group (median [IQR] 10.1 [7.9-14.2] ng/ml vs 6.3 [3.9-7] ng/ml, respectively; p = 0.005). The FABP4 level was positively correlated with HbA 1c at presentation and inversely correlated with venous blood pH and bicarbonate levels (p < 0.05 for all). Following initiation of insulin therapy, a marked reduction in FABP4 was observed in all children. An FABP4 level of 7.22 ng/ml had a sensitivity of 86% and a specificity of 78% for the diagnosis of DKA, with an area under the receiver operating characteristic curve of 0.78 (95% CI 0.6, 0.95; p = 0.008). In a streptozotocin-induced diabetes mouse model, Fabp4 -/- mice exhibited marked hypoinsulinaemia and hyperglycaemia similar to WT mice but displayed no significant increase in β-hydroxybutyrate and were protected from ketoacidosis., Conclusions/interpretation: FABP4 is suggested to be a necessary regulator of ketogenesis in insulin-deficient states., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Dr. William Beecher Scoville (1906-1984) is a giant figure in the history of neurosurgery, well known by the public for his operation on Patient H.M. He developed dozens of neurosurgical instruments and techniques, with many tools named after him that are still widely used today. He founded numerous neurosurgical societies around the world. He led the movement in psychosurgery, developing the technique of selective orbital undercutting and performing hundreds of lobotomies throughout his career. However, his many contributions to the advancement of neurosurgery have not been well described in the medical literature. To bridge the knowledge gap, this article seeks to detail the life and career of William Beecher Scoville and bring to attention the enduring impact of his work.

Age-related cardiac amyloidosis results from deposits of wild-type tranthyretin amyloid (ATTRwt) in cardiac tissue. ATTR may play a role in carpal tunnel syndrome (CTS) and in spinal stenosis (SS), indicating or presaging systemic amyloidosis. We investigated consecutive patients undergoing surgery for SS for ATTR deposition in the resected ligamentum flavum (LF) and concomitant risk of cardiac amyloidosis. Each surgical specimen (LF) was stained with Congo red, and if positive, the amyloid deposits were typed by mass spectrometry. Patients with positive specimens underwent standard of care evaluation with fat pad aspirates, serum and urine protein electrophoresis with immunofixation, free light-chain assay, TTR gene sequencing and technetium 99 m-pyrophosphate-scintigraphy. In 2018-2019, 324 patients underwent surgery for SS and 43 patients (13%) had ATTR in the LF with wild-type TTR gene sequences. Two cases of ATTRwt cardiac amyloidosis were diagnosed and received treatment. In this large series, ATTRwt was identified in 13% of the patients undergoing laminectomy for SS. Patients with amyloid in the ligamentum flavum were older and had a higher prevalence of CTS, suggesting a systemic form of ATTR amyloidosis involving connective tissue. Further prospective study of patients with SS at risk for systemic amyloidosis is warranted.

Objective: Spinal anesthesia (SA) is an alternative to general anesthesia (GA) for lumbar spine surgery, including complex instrumented fusion, although there are relatively few outcome data available. The authors discuss their experience using SA in a modern complex lumbar spine surgery practice to describe its utility and implementation., Methods: Data from patients receiving SA for lumbar spine surgery by one surgeon from March 2017 to December 2020 were collected via a retrospective chart review. Cases were divided into nonfusion and fusion procedure categories and analyzed for demographics and baseline medical status; pre-, intra-, and postoperative events; hospital course, including Acute Pain Service (APS) consults; and follow-up visit outcome data., Results: A total of 345 consecutive lumbar spine procedures were found, with 343 records complete for analysis, including 181 fusion and 162 nonfusion procedures and spinal levels from T11 through S1. The fusion group was significantly older (mean age 65.9 ± 12.4 vs 59.5 ± 15.4 years, p < 0.001) and had a significantly higher proportion of patients with American Society of Anesthesiologists (ASA) Physical Status Classification class III (p = 0.009) than the nonfusion group. There were no intraoperative conversions to GA, with infrequent need for a second dose of SA preoperatively (2.9%, 10/343) and rare preoperative conversion to GA (0.6%, 2/343) across fusion and nonfusion groups. Rates of complications during hospitalization were comparable to those seen in the literature. The APS was consulted for 2.9% (10/343) of procedures. An algorithm for the integration of SA into a lumbar spine surgery practice, from surgical and anesthetic perspectives, is also offered., Conclusions: SA is a viable, safe, and effective option for lumbar spine surgery across a wide range of age and health statuses, particularly in older patients and those who want to avoid GA. The authors' protocol, based in part on the largest set of data currently available describing complex instrumented fusion surgeries of the lumbar spine completed under SA, presents guidance and best practices to integrate SA into contemporary lumbar spine practices.

During pregnancy, fetal glucose production is suppressed, with rapid activation immediately postpartum. Fatty acid-binding protein 4 (FABP4) was recently demonstrated as a regulator of hepatic glucose production and systemic metabolism in animal models. Here, we studied the role of FABP4 in regulating neonatal glucose hemostasis. Serum samples were collected from pregnant women with normoglycemia or gestational diabetes at term, from the umbilical circulation, and from the newborns within 6 hours of life. The level of FABP4 was higher in the fetal versus maternal circulation, with a further rise in neonates after birth of approximately 3-fold. Neonatal FABP4 inversely correlated with blood glucose, with an approximately 10-fold increase of FABP4 in hypoglycemic neonates. When studied in mice, blood glucose of 12-hour-old WT, Fabp4-/+, and Fabp4-/- littermate mice was 59 ± 13 mg/dL, 50 ± 11 mg/dL, and 43 ± 11 mg/dL, respectively. Similar to our observations in humans, FABP4 levels in WT mouse neonates were approximately 8-fold higher compared with those in adult mice. RNA sequencing of the neonatal liver suggested altered expression of multiple glucagon-regulated pathways in Fabp4-/- mice. Indeed, Fabp4-/- liver glycogen was inappropriately intact, despite a marked hypoglycemia, with rapid restoration of normoglycemia upon injection of recombinant FABP4. Our data suggest an important biological role for the adipokine FABP4 in the orchestrated regulation of postnatal glucose metabolism.