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The lower 3.5 km of Eighteenmile Creek, a tributary to Lake Ontario in New York, was designated as an Area of Concern (AOC) in 1985 under the Great Lakes Water Quality Agreement due to extensive contamination of bed sediments by polychlorinated biphenyls (PCBs) and other toxicants. Five beneficial use impairments (BUIs) have been identified in this AOC, including degraded fish and wildlife populations. We surveyed fish communities in the Eighteenmile Creek AOC and in a comparable section of a nearby reference stream (Oak Orchard Creek) during June 2019 to infer whether legacy contaminants are currently impairing fish communities in the AOC to an extent that they differ from the regional reference condition. Estimates of community abundance, biomass, diversity, and fish condition from each system were compared using a noninferiority testing framework. Biomass, diversity, and fish condition in the Eighteenmile Creek AOC were similar or superior to that in Oak Orchard Creek, while abundance was 20% lower in the AOC. These findings and those of a 2007 sampling effort suggest that fish communities in the Eighteenmile Creek AOC are not impaired despite recent studies indicating that PCBs are bioaccumulating in fish tissues at 1–2 orders of magnitude above background levels. Future assessments in the Eighteenmile Creek AOC might focus on the condition of benthic macroinvertebrate communities and potential toxicity of local contaminants to piscivorous wildlife in order to fully address the remaining aspects of the fish and wildlife populations beneficial use impairment.

Background Sellar masses (SM) frequently present with insidious hormonal dysfunction. We previously showed that, by utilizing a combined reflex/reflecting approach involving a laboratory clinician (LC) on common endocrine test results requested by non-specialists, and subsequently adding further warranted tests, previously undiagnosed pituitary disorders can be identified. However, manually employing these strategies by an LC is not feasible for wider screening of pituitary disorders. Objective The aim of this study was to compare the accuracy and financial impact of an Artificial Intelligence (AI) based, fully computerized reflex protocol with manual reflex/reflective intervention protocol led by an LC. Methods We developed a proof-of-concept AI-based framework to fully computerize multi-stage reflex testing protocols for pituitary dysfunction using automated reasoning methods. We compared the efficacy of this AI-based protocol with a reflex/reflective protocol based on manually curated retrospective data in identifying pituitary dysfunction based on 12 months of laboratory testing. Results The AI-based reflex protocol, as compared with the manual protocol, would have identified laboratory tests for add-on that either directly matched or included all manual add-on tests in 92% of cases, and recommended a similar specialist referral in 90% of the cases. The AI-based protocol would have issued 2.8 times the total number of manual add-on laboratory tests at an 85% lower operation cost than the manual protocol when considering marginal test costs, technical staff and specialist salary. Conclusion/Discussion Our AI-based reflex protocol can successfully identify patients with pituitary dysfunction, with lower estimated laboratory cost. Future research will focus on enhancing the protocol’s accuracy and incorporating the AI-based reflex protocol into institutional laboratory and hospital information systems for the detection of undiagnosed pituitary disorders.

Background: Mental health disorders are a common sequelae of traumatic brain injury (TBI) and are associated with worse health outcomes including increased mental health care utilization. This study addresses the methodical limitations of previous studies by examining the effect of TBI on mental health care utilization using propensity score matching analysis. Methods: Using data from a national survey, this study assessed mental health care utilization among those with a TBI, compared with a non-injured control group. Propensity score matching for age, sex, education, income, marital status, race, mental health comorbidities, and chronic conditions in a 4:1 ratio using nearest neighbor was performed. Conditional logistic regression then compared matched patients in terms of mental health care utilization. E-value sensitivity analysis was used to assess how strong an unmeasured confounder would have to be to explain away an observed relationship. Results: The matched study sample included 76,727 TBI patients and 307,510 non-injured controls with significantly improved balance in all baseline covariates. After conditional regression of the propensity-matched cohort, TBI remained a significant predictor of mental health care utilization (95% CI, 1.38-3.67), showing a 2.25-fold increased probability of mental health care utilization in TBI patients. Conclusions: This study is the first to evaluate the probability of mental health care utilization in TBI patients through a well-matched national cohort. TBI patients were more than twice as likely to use health care services for mental health complaints relative to those who were uninjured. Further longitudinal research is needed to evaluate the long-term mental health care utilization of TBI patients.

Traumatic brain injury (TBI) is a leading cause of death and disability among adults. Falls and motor vehicle collisions (MVCs) are the most common causes of TBI hospitalizations in Canada. The purpose of this study was to determine whether, at the provincial level, there have been significant changes in the injury rate and causes of major TBI. This was a retrospective cohort study of all patients in Nova Scotia who presented with major TBI (Abbreviated Injury Scale Head score ≥ 3) between 2002 and 2018. Prospectively entered data were collected from the Nova Scotia Trauma Registry. Annual injury rates were calculated based on 100,000 population (all ages) using population estimates from Statistics Canada. Linear regression was performed to analyze annual trends of major TBI within the province. There were 5590 major TBI patients in Nova Scotia during the 16-year study period. The overall annual rate of major TBI was 37 per 100,000 population. There was a 39% increase in the rate of major TBI over the study period (r = − 0.72, R2 = 0.51, p

Frame registration is a critical step to ensure accurate electrode placement in stereotactic procedures such as stereoelectroencephalography (SEEG) and is routinely done by merging a computed tomography (CT) scan with the preoperative magnetic resonance (MR) examination. Three-dimensional fluoroscopy (XT) has emerged as a method for intraoperative electrode verification following electrode implantation and more recently has been proposed as a registration method with several advantages. We compared the accuracy of SEEG electrode placement by frame registration with CT and XT imaging by analyzing the Euclidean distance between planned and post-implantation trajectories of the SEEG electrodes to calculate the error in both the entry (EP) and target (TP) points. Other variables included radiation dose, efficiency, and complications. Twenty-seven patients (13 CT and 14 XT) underwent placement of SEEG electrodes (319 in total). The mean EP and TP errors for the CT group were 2.3 mm and 3.3 mm, respectively, and 1.9 mm and 2.9 mm for the XT group, with no statistical difference (p = 0.75 and p = 0.246). The time to first electrode placement was similar (XT, 82 ± 10 min; CT, 84 ± 22 min; p = 0.858) and the average radiation exposure with XT (234 ± 55 mGy*cm) was significantly lower than CT (1245 ± 123 mGy*cm) (p < 0.0001). Four complications were documented with equal incidence in both groups. The use of XT as a method for registration resulted in similar implantation accuracy compared with CT. Advantages of XT are the substantial reduction in radiation dose and the elimination of the need to transfer the patient out of the room which may have an impact on patient safety and OR efficiency.

Background:Patients with sellar masses undergoing transsphenoidal surgery (TSS) frequently develop endocrine dysfunction; therefore, in-hospital endocrinology consultation (IHEC) is recommended. However, we wondered whether routine endocrinology assessment of all TSS patients is always necessary.Methods:We developed an IHEC Physician’s Guide to identify patients who would require peri-operative IHEC. An analysis of all patients undergoing TSS for a sellar mass over a 4-year period was conducted to assess the predictive value of the IHEC Physician’s Guide in identifying patients who required IHEC.Results:A total of 116 patients underwent TSS; 24 required IHEC. As expected, the risk of endocrine complications requiring peri-operative endocrine management was significantly higher in the IHEC group versus no-IHEC group (96% vs. 1%; p < 0.001). The negative predictive value of the IHEC Physician’s Guide in identifying patients who did not require IHEC was 0.99 (95% CI 0.9409–0.9997); Fisher’s exact test, p < 0.001), meaning that the IHEC Physician’s Guide successfully identified all but one patient who truly required IHEC.Conclusion:Results from our study show that most patients do not need IHEC after TSS and that those patients requiring IHEC can be reliably predicted at surgery by using a simple IHEC Physician’s Guide.

This paper details a linear-elastic approach to modeling crosstie-ballast interfacial load distribution in a railroad timber crosstie trackbed using RISA 3D, a finite element modeling software. RISA results closely mirrored experimental findings with some slight deviation as discussed in the paper. The modeling methodology outlined here advances previous trackbed research at the University of Kentucky, U.S., and could be used in future trackbed finite element analyses for design or research in load path distribution and load magnitude predictability. This paper details the approach used to model a timber crosstie trackbed superstructure, including initial troubleshooting stages, and explains the derivation of program input variables. A sensitivity analysis performed on the main model determined the workable extent of linearity. The analysis also examined the effect of a poor/muddy trackbed support loading condition. The paper concludes with potential recommendations in relation to the work.

Patients with sellar masses (SM) frequently have secondary hormonal deficiency (SHD) at initial presentation. While larger SM are more likely to present with SHD, it is unclear whether SHD at presentation is influenced by the type of SM.We conducted a retrospective analysis of patients with SM prospectively enrolled in our comprehensive provincial neuropituitary registry between November 2005 and December 2018. SM were subdivided based on size: 1 cm, 1-1.9 cm, 2-2.9 cm, and 3 cm.A total of 914 patients met the inclusion criteria, including: 346 nonfunctioning adenomas (NFA), 261 prolactinomas (PRLoma), 51 growth hormone adenomas, 36 adrenocorticotropic adenomas, 93 Rathke's cleft cysts, 70 craniopharyngiomas and 57 meningiomas. The overall rate of SHD at presentation was highest in PRLoma (62.8%) and craniopharyngiomas (64.3%) and lowest in meningiomas (14%). While larger SM were significantly more likely to have SHD, the rate of SHD within each group was significantly different despite similar size (p 0.001). Of the two largest groups of SM (NFA and PRLoma), NFA had significantly higher odds ratio (3.34, CI 1.89-5.89) of having multiple SHDs when compare with PRLoma, even when corrected for age, gender and size of tumor (p 0.001).Our study shows that the rate and distribution of SHD in SM vary dependent upon the size of the tumor and specific pathology; in particular, NFA are more likely to present with multiple SHDs. Our data will help clinicians in determining adequate hormonal testing strategy for different SM.

Transorbital penetration accounts for one-quarter of the penetrating head injuries (PHIs) in adults and half of those in children. Injuries that traverse (with complete penetration of) the brainstem are often fatal, with survivors rarely seen in clinical practice. Here, the authors describe the case of a 16-year-old male who suffered and recovered from an accidental transorbital PHI traversing the brainstem—the first case of complete neurological recovery following such injury. Neuroimaging captured the trajectory of the initial injury. A delayed-onset carotid cavernous fistula and the subsequent development of internal carotid artery pseudoaneurysms were managed by endovascular embolization.The authors also review the relevant literature. Sixteen cases of imaging-confirmed PHI traversing the brainstem have been reported, 14 involving the pons and 12 penetrating via the transorbital route. Management and outcome of PHI are informed by object velocity, material, entry point, trajectory, relationship to neurovascular structures, and the presence of a retained foreign body. Trauma resuscitation is followed by a careful neurological examination and appropriate neuroimaging. Ophthalmological examination is performed if transorbital penetration is suspected, as injuries may be occult; the potential for neurovascular complications highlights the value of angiography. The featured case shows that complete recovery is possible following injury that traverses the brainstem.

Due to super elevation and centrifugal force, close attention is needed to lateral stability of cargo when the train negotiates curves. To guarantee the security of cargo on wagons, proper blocking...

The mechanisms underlying the complications of mild traumatic brain injury, including post-concussion syndrome, post-impact catastrophic death, and delayed neurodegeneration remain poorly understood. This limited pathophysiological understanding has hindered the development of diagnostic and prognostic biomarkers and has prevented the advancement of treatments for the sequelae of mild traumatic brain injury. We aimed to characterize the early electrophysiological and neurovascular alterations following repetitive mild traumatic brain injury and sought to identify new targets for the diagnosis and treatment of individuals at risk of severe post-impact complications. We combined behavioural, electrophysiological, molecular, and neuroimaging techniques in a rodent model of repetitive mild traumatic brain injury. In humans, we used dynamic contrast-enhanced MRI to quantify blood–brain barrier dysfunction after exposure to sport-related concussive mild traumatic brain injury. Rats could clearly be classified based on their susceptibility to neurological complications, including life-threatening outcomes, following repetitive injury. Susceptible animals showed greater neurological complications and had higher levels of blood–brain barrier dysfunction, transforming growth factor β (TGFβ) signalling, and neuroinflammation compared to resilient animals. Cortical spreading depolarizations were the most common electrophysiological events immediately following mild traumatic brain injury and were associated with longer recovery from impact. Triggering cortical spreading depolarizations in mild traumatic brain injured rats (but not in controls) induced blood–brain barrier dysfunction. Treatment with a selective TGFβ receptor inhibitor prevented blood–brain barrier opening and reduced injury complications. Consistent with the rodent model, blood–brain barrier dysfunction was found in a subset of human athletes following concussive mild traumatic brain injury. We provide evidence that cortical spreading depolarization, blood–brain barrier dysfunction, and pro-inflammatory TGFβ signalling are associated with severe, potentially life-threatening outcomes following repetitive mild traumatic brain injury. Diagnostic-coupled targeting of TGFβ signalling may be a novel strategy in treating mild traumatic brain injury.

Since traffic crashes involve complex interactions among drivers, vehicles, roadway, traffic, and environmental elements and not all of the factors that could potentially determine the occurrences of traffic crashes can be observed and measured, new methods are needed to better perform traffic crash estimations and predictions and address the unobserved heterogeneity issues in crash data. Unlike the conventional methods, which generally are the statistical models with the observed crash counts as the dependent variables and the factors affecting the likelihood of a traffic crash as the independent variables, a dynamic state-space model with deep learning is proposed to analyze the traffic crashes. The proposed model includes three modules, an unsupervised feature learning module to identify functional network between the explanatory variables and the feature representations, a supervised fine tuning module to perform crash occurrence likelihood estimations, and a dynamic state-space module to perform crash count predictions. A multivariate Tobit model is incorporated in the supervised fine tuning module as the regression layer to account for the heterogeneity issues in correlated crash data. The results of deep learning are fed to the dynamic state-space model that contains a dynamic equation governing the state dynamics to improve the performances of estimation and prediction. The proposed model was applied to the dataset that was obtained from Knox County in Tennessee to validate the model effectiveness and efficiency. The results show that the proposed model has superior performances in terms of estimation and prediction power compared to the SVM and Random Forest (RF) models. The overall performances of the proposed model for all crashes show an 50.559% RMSD improvement over the SVM models and an 57.867% RMSD improvement over the RF models. The findings indicate that the feature learning module identifies relational information between the explanatory variables and feature representations, which reduces the dimensionality of the input and preserves the original information. The proposed model that includes a multivariate Tobit regression layer in the supervised fine tuning module can better account for differential distribution patterns in traffic crashes across injury severities and provides superior crash occurrence likelihood estimation results. The findings suggest that the proposed model can better address the heterogeneity issues in correlated crash data and is a superior alternative for traffic crash estimations and predictions.

Background: We report a case of an intraosseous cavernous hemangioma originating from the middle turbinate that expanded into the anterior skull base, without traversing the cribriform plate. Methods: The mass was found incidentally after a computed tomography head was ordered for unrelated reasons. On questioning, the patient denied any nasal symptoms. Magnetic resonance imaging showed an enhancing mass and the radiological imaging supported a broad differential. Results: The lesion was removed by endoscopic image-guided surgery, and the pathology was that of a benign intraosseous cavernous hemangioma. There was no residual hemangioma on postoperative imaging and the nasal mucosa healed well. This is the first report of an intraosseous cavernous hemangioma of the middle turbinate showing superior expansion to the anterior skull base. Conclusion: This case demonstrates the extent to which cavernous hemangiomas may expand into surrounding tissues. While these lesions are uncommon, they can be considered as part of a broad differential diagnosis of sinonasal tumors.

Frame registration is a critical step to ensure accurate electrode placement in stereotactic procedures such as stereoelectroencephalography (SEEG) and is routinely done by merging a computed tomography (CT) scan with the preoperative magnetic resonance (MR) examination. Three-dimensional fluoroscopy (XT) has emerged as a method for intraoperative electrode verification following electrode implantation and more recently has been proposed as a registration method with several advantages.We compared the accuracy of SEEG electrode placement by frame registration with CT and XT imaging by analyzing the Euclidean distance between planned and post-implantation trajectories of the SEEG electrodes to calculate the error in both the entry (EP) and target (TP) points. Other variables included radiation dose, efficiency, and complications.Twenty-seven patients (13 CT and 14 XT) underwent placement of SEEG electrodes (319 in total). The mean EP and TP errors for the CT group were 2.3 mm and 3.3 mm, respectively, and 1.9 mm and 2.9 mm for the XT group, with no statistical difference (p = 0.75 and p = 0.246). The time to first electrode placement was similar (XT, 82 ± 10 min; CT, 84 ± 22 min; p = 0.858) and the average radiation exposure with XT (234 ± 55 mGy*cm) was significantly lower than CT (1245 ± 123 mGy*cm) (p0.0001). Four complications were documented with equal incidence in both groups.The use of XT as a method for registration resulted in similar implantation accuracy compared with CT. Advantages of XT are the substantial reduction in radiation dose and the elimination of the need to transfer the patient out of the room which may have an impact on patient safety and OR efficiency.

Introduction Previous studies have shown that simulation is an acceptable method of training in nursing education. The objectives of this study were to determine the effectiveness of tablet-based simulation in learning neurosurgical instruments and to assess whether skills learnt in the simulation environment are transferred to a real clinical task and retained over time. Methods A randomised controlled trial was conducted. Perioperative nurses completed three consecutive sessions of a simulation. Group A performed simulation tasks prior to identifying real instruments, whereas Group B (control group) was asked to identify real instruments prior to the simulation tasks. Both groups were reassessed for knowledge recall after 1 week. Results Ninety-three nurses completed the study. Participants in Group A, who had received tablet-based simulation, were 23% quicker in identifying real instruments and did so with better accuracy (93.2% vs 80.6%, p Conclusion This is the first study to assess the effectiveness of tablet-based simulation training for instrument recognition by perioperative nurses. Our results demonstrate that instrument knowledge acquired through tablet-based simulation training results in improved identification and retained recognition of real instruments.

Introduction: Stereotactic procedures are routinely performed for brain biopsies, deep brain stimulation, and placement of stereoelectroencephalography (SEEG) electrodes for epilepsy. The recently developed Stealth Autoguide (Medtronic, Minneapolis, MN, USA) device does not require patients to don a stereotactic frame. In this preclinical study, we sought to quantitatively compare the Stealth Autoguide robotic system to 2 devices commonly used in clinical practice: the Navigus biopsy system (Medtronic) and the Leksell stereotactic frame (Elekta Ltd., Stockholm, Sweden). Methods: In the first experimental setup, we compared target accuracy of the Stealth Autoguide to the Navigus system by using phantom heads filled with gelatin to simulate the brain tissue. In the second experimental setup, we inserted SEEG electrodes to targets within cadaveric heads in a simulated operating room environment. Results: Using a homogeneous gelatin-filled phantom 3D reconstruction of a human head, we found that using the Stealth Autoguide system, while maintaining accuracy, was faster to use than the Navigus system. In our simulated operating room environment using nonliving human cadaveric heads, we found the accuracy of the Stealth Autoguide robotic device to be comparable to that of the Leksell frame. Discussion/Conclusion: These results compare the use of the Stealth Autoguide robotic guidance system with commonly used stereotactic devices, and this is the first study to compare its use and accuracy with the Leksell frame. These findings provide mounting evidence that Stealth Autoguide will have potential clinical uses in various stereotactic neurosurgical procedures.

Rail-trespassing crashes that involve various levels of injuries to pedestrians are under-researched. Rail trespassing could occur at crossings where pedestrians are present at the wrong time and at non-crossings where pedestrians are not legally allowed to be present. This paper presents a comparative study examining rail-trespassing crashes in two contexts: highway-rail grade crossings vs. non-crossings. How pre-crash trespassing behaviors and other factors (e.g., crash time, locations, and socio-demographics) differ between grade crossings and non-crossings are explored. The analysis relies on a ten-year (2006-2015) database of rail-pedestrian trespassing crash records extracted from a Federal Railroad Administration safety database. Of these 7157 rail-pedestrian trespassing crashes, 6236 (87%) occurred at non-crossings, while 921 (13%) occurred at grade crossings. About 60% of the crashes were fatal at both crossings and non-crossings. The most prevalent pre-crash trespassing behavior is running or walking, 63% at grade crossings and 44% at non-crossings. Lying or sleeping account for 29% of non-crossing crashes, whereas they are 3.6% at grade crossings. A unique aspect of the study is that a diverse set of variables based on geographic variations across counties along with crash or injury data are modeled. Considering the data structure and heterogeneity that may exist due to unobserved factors, the multilevel mixed-effect ordered logistic regressions models are estimated. The results show that the correlates of injury severity differ across highway-rail grade crossings and non-crossings. For example, lying or sleeping on or near tracks contributed to higher chances of fatal injury in both contexts, however, they were relatively more injurious at grade crossings. The analytical results can provide guidance on railway safety improvement plans.

This paper describes the development of a method to measure railroad track tie/ballast interfacial pressures using pressure cells specially designed for granular materials. Repeat measurements were taken during a several-month period on a Norfolk Southern Corporation high-tonnage mainline. The research employed new wood crossties routed so pressure cells could be recessed within the ties. Thus, the active surfaces of the pressure cells were flush with the tie bottoms. Cabling was run through a recess to the tie end. This greatly reduced the likelihood of damage to the instrumentation during track surfacing and lining activity. The ties were installed such that multiple cells were directly under consecutive rail seats of one rail. Several ties also had cells either at the center or the rail seat of the opposite rail. The researchers expended considerable effort to provide consistent ballast conditions for the instrumented ties and adjacent, undisturbed (transition) ties. Norfolk Southern crews surfaced and tamped through and on either side of the test section. This, plus consolidation through normal accruing train traffic, resulted in consistent measurements through the section. The paper presents ballast pressure magnitudes and distributions and discusses results, including the effects of variable ballast support, wheel loadings, and impact loadings. Typical vertical ballast pressure measurements directly under the rail seat, with compacted ballast and minimal impact forces ranged from 20 to 30 psi (140 to 210 kPa) under the heaviest common revenue wheel loadings.

Objective The clinical presentation of pituitary dysfunction is typically variable and may often be insidious, resulting in delayed diagnosis by up to decades. The complexity of presentation and difficulty in pattern recognition of first line hormone tests result in challenges in early diagnosis of this condition. The aim of this study was to determine the impact of reflective testing and interpretive commenting on the early detection and management of such cases from primary care. Methods Prospective audit over 12 months in which first line pituitary target organ hormones were identified via a reflex algorithm in the laboratory information system. Selected tests were reviewed by a laboratory clinician and decision made on reflective testing and interpretive commenting based on available clinical information and previous result trends. Patients who had a laboratory intervention were followed up to determine the clinical outcome. Results Out of 1099 patients identified, additional testing was made for 214. Interpretative comments were subsequently added to reports of 196 patients, 48 (25%) of whom were referred to endocrinology and 35 (73%) of these were directly related to the laboratory intervention. Eleven other patients had outcomes related to the intervention. Pituitary related conditions (insufficiency and/or adenoma) were found in 29 patients, 24 of which were identified as a result of laboratory intervention. Conclusions This study highlights the clinical value of laboratory intervention in aiding early detection of pituitary dysfunction and may avoid the disease burden of delayed management.

Classification yards play a significant role in railroad freight transportation and are often considered bottlenecks for railroad networks. Based on a generic yard simulation model, the model in the presented study fits the Bureau of Public Roads function, which is widely used in highway capacity to represent the volume–dwell time relationship. The proposed analytical model incorporates major features of rail yards, such as the number and capacity of tracks in each area, the number of engines and humps, the humping speed, and the assemble rate. The model is validated by historical data from 16 classification yards of Class I railroads in the United States. The results show that the proposed model can generate precise capacity data of rail yard, as well as the dwell time of rail cars in yards. The dwell time increases sharply when the volume is greater than the capacity of a rail yard. The identified relationship may help a railroad analyze its network at the macro level and therefore improve the systemwide capacity and efficiency.

Lateral impact damage from over-height vehicle collisions with bridge superstructures is of increasing concern in the United States. However this issue is not fully addressed in current bridge specifications. Previous researchers have conducted a number of small-scale tests to study the impact process. Also, the finite element method has largely been used to analyze the complicated collision mechanism. This paper provides an opportunity for full-scale lateral impact testing of a prestressed concrete girder, which leads to a realistic level of damage and mechanism analysis. A full-scale lateral impact testing facility was designed and built on a construction site in Knoxville, Tennessee. The over-height vehicle impact was simulated by impacting the bottom of an AASHTO Type I prestressed concrete girder with an impact cart. This paper describes the details of the impact testing facility as well as the response of the prestressed concrete girder during lateral impact. The collected test data were calibrated by using finite element software ABAQUS.

BACKGROUND: Secondary hormonal deficiency (SHD) is common in patients with sellar masses (SM); however, it is unclear if the rate and type of SHD at presentation is related to the size or type of SM. We conducted a study comparing SHD in various SM based on pathology and size at presentation. METHODS: A retrospective analysis of all SM in a tertiary care neuropituitary program, enrolled between November 2005 and December 2018, was conducted based on type of SM and maximum tumor size, comparing rate of secondary hypogonadism (SHG), secondary hypothyroidism (SHT), secondary hypoadrenalism (SHA), growth hormone deficiency (GHD) and diabetes insipidus (DI). RESULTS: A total of 914 patients were identified including: nonfunctioning adenoma (NFA) = 346, prolactinoma (PRLoma) = 261, growth hormone (GH) adenoma = 51, ACTH adenoma = 36, meningioma = 57, craniopharyngioma (cranio) = 70 and Rathke’s cleft cyst (RCC) = 93. SM were further subdivided based on initial size into < 9mm (group A), 10-19mm (group B), 20-29mm (group C) and ≥ 30 mm (group D). The overall SHD (%), single vs. multiple SHD (%) and most prevalent SHD, respectively, for each group were as follow. Group A - NFA (10%, 56% vs. 44%, SHG and SHT), PRLoma (48%, 90% vs. 10%, SHG), GH adenoma (13%, 100% vs 0, SHG), ACTH adenoma (29%, 83% vs. 17%, SHG), cranio (50%, 100% vs. 0, GHD) and RCC (11%, 100% vs. 0, SHG); Group B - NFA (35%, 43% vs. 57%, SHG), PRLoma (73%, 77% vs. 23%, SHG), GH adenoma (23%, 71% vs. 29%, SHG), ACTH adenoma (30%, 67% vs. 33%, SHG), meningioma (5%, 0 vs. 100%, SHG and SHA), cranio (48%, 73% vs. 27%, SHT), RCC (17%, 43% vs. 57%, SHT); Group C - NFA (64%, 28% vs. 72%, SHG), PRLoma (78%, 50% vs. 50%, SHG), GH adenoma (75%, 50% vs. 50%, SHG), ACTH adenoma (100%, 33% vs. 67%, SHG), meningioma (16%, 100% vs. 0, SHT), cranio (70%, 38% vs. 62%, SHG), RCC (41%, 29% vs. 71%, SHG): Group D - NFA (83%, 40% vs. 60%, SHG), PRLoma (100%, 47% vs. 53%, SHG), GH adenoma (80%, 0 vs. 100%, SHG and SHT), meningioma (27%, 75% vs. 25%, SHG), cranio (88%, 36% vs. 64%, SHG) [all p

Bicycle-related injuries are a leading cause of child and youth hospitalizations in Canada. The use of helmets while bicycling reduces the risk of brain injuries. This study investigated the long-term effect of legislation coupled with enforcement to improve helmet use rates. We conducted a longitudinal observational study of helmet use at 9, 11, and 14 years after bicycle helmet legislation was enacted. Data were compared to baseline observations collected after legislation was passed in 1997. A comprehensive enforcement and educational diversion program, Operation Headway-Noggin Knowledge (OP-NK), was developed and implemented in partnership with regional police during the study period. Helmet use was sustained throughout the post-legislation period, from 75.3 % in the year legislation was enacted to 94.2 % 14 years post-legislation. The increase in helmet use was seen among all age groups and genders. Helmet legislation was not associated with changes in bicycle ridership over the study years. OP-NK was associated with improved enforcement efforts as evidenced by the number of tickets issued to noncompliant bicycle riders. This observational study spans a 16-year study period extending from pre-legislation to 14 years post all-age bicycle helmet legislation. Our study results demonstrate that a comprehensive approach that couples education and awareness with ongoing enforcement of helmet legislation is associated with long-term sustained helmet use rates. The diversion program described herein is listed among best practices by the Public Health Agency of Canada.

Since highway safety laws vary greatly from state to state in the U.S., there is a need to analyze the effectiveness and performances of the implemented highway safety laws. The random-parameter zero-truncated negative binomial (RZTNB) models are proposed to analyze the effects of highway safety laws on fatal crashes at state levels. The results show that the proposed models are useful in describing the relationships between the fatal crashes and the explanatory variables with better goodness of fit. By accounting for the heterogeneities, the RZTNB model outperforms the negative binomial model and reveals new insights. The findings indicate that (1) compared to the secondary ban, the primary handheld cellphone ban is more effective; (2) establishing reasonable and acceptable speed limits can enhance the traffic safety; and (3) the implemented speed camera system and ignition interlock device have weaknesses and alternative methods should be considered when upgrading laws and regulations.

Objectives Pituitary incidentalomas (PI) are frequently found on brain imaging. Despite their high prevalence, little is known about their long-term natural history and there are limited guidelines on how to monitor them. Methods We conducted a retrospective study to compare epidemiological characteristics at presentation and the natural history of PI in population-based vs referral-based registries from two tertiary-care referral centers in Canada. Results A total of 328 patients with PI were included, of whom 73% had pituitary adenomas (PA) and 27% had non-pituitary sellar masses. The commonest indications for imaging were headache (28%), dizziness (12%) and stroke/transient ischemic attack (TIA) (9%). There was a slight female preponderance (52%) with a median age of 55 years at diagnosis; 71% presented as macroadenomas (>10mm). Of PA, 25% were functioning tumors and at presentation 36% of patients had evidence of secondary hormonal deficiency (SHD). Of the total cohort, 68% were treated medically or conservatively whereas 32% required surgery. Most tumors (87% in non-surgery and 68% in post-surgery group) remained stable during follow-up. Similarly, 84% of patients in the non-surgery and 73% in the surgery group did not develop additional SHD during follow-up. The diagnosis of non-functioning adenoma was a risk factor for tumor enlargement and a change in SHD status was associated with a change in tumor size. Conclusions Our data suggest that most PI seen in tertiary-care referral centers present as macroadenomas and may frequently be functional, often requiring medical or surgical intervention.

This paper proposes a random-parameter bivariate zero-inflated negative binomial (RBZINB) regression model for analyzing the effects of investigated variables on crash frequencies. A Bayesian approach is employed as the estimation method, which has the strength of accounting for the uncertainties related to models and parameter values. The modeling framework has been applied to the bivariate injury crash counts obtained from 1000 intersections in Tennessee over a five-year period. The results reveal that the proposed RBZINB model outperforms other investigated models and provides a superior fit. The proposed RBZINB model is useful in gaining new insights into how crash occurrences are influenced by the risk factors. In addition, the empirical studies show that the proposed RBZINB model has a smaller prediction bias and variance, as well as more accurate coverage probability in estimating model parameters and crash-free probabilities.

The neural cell adhesion molecule (NCAM) is involved in developmental processes and age-associated cognitive decline; however, little is known concerning the effects of NCAM in the visual system during aging. Using anatomical, electrophysiological, and behavioral assays, we analyzed age-related changes in visual function of NCAM deficient (−/−) and wild-type mice. Anatomical analyses indicated that aging NCAM −/− mice had fewer retinal ganglion cells, thinner retinas, and fewer photoreceptor cell layers than age-matched controls. Electroretinogram testing of retinal function in young adult NCAM −/− mice showed a 2-fold increase in a- and b-wave amplitude compared with wild-type mice, but the retinal activity dropped dramatically to control levels when the animals reached 10 months. In behavioral tasks, NCAM −/− mice had no visual pattern discrimination ability and showed premature loss of vision as they aged. Together, these findings demonstrate that NCAM plays significant roles in the adult visual system in establishing normal retinal anatomy, physiology and function, and in maintaining vision during aging.

Background: Sellar masses (SM) are mostly benign growths of pituitary or nonpituitary origin that are increasingly encountered in clinical practice. To date, no comprehensive population-based study has reported the epidemiology of SM from North America. Aim: To determine the epidemiology of SM in the province of Nova Scotia, Canada. Methods: Data from all pituitary-related referrals within the province were prospectively collected in interlinked computerized registries starting in November 2005. We conducted a retrospective analysis on all patients with SM seen within the province between November 2005 and December 2013. Results: A total of 1107 patients were identified, of which 1005 were alive and residing within the province. The mean age at presentation was 44.6±18 years, with an overall female preponderance (62%) and a population prevalence rate of 0.1%. Of patients with SM, 837 (83%) had pituitary adenomas and 168 (17%) had nonpituitary lesions. The relative prevalence and standardized incidence ratio, respectively, of various SM were: nonfunctioning adenomas (38.4%; 2.34), prolactinomas (34.3%; 2.22), Rathke’s cyst (6.5%; 0.5), growth hormone–secreting adenomas (6.5%; 0.3), craniopharyngiomas (4.5%; 0.2), adrenocorticotropic hormone–secreting adenomas (3.8%; 0.2), meningiomas (1.9%), and others (3.9%; 0.21). At presentation, 526 (52.3%) had masses ≥1 cm, 318 (31.6%) at Conclusions: This is the largest North American study to date to assess the epidemiology of SM in a large stable population. Given their significant prevalence in the general population, more studies are needed to evaluate the natural history of these masses and to help allocate appropriate resources for their management.

Vision loss has long since been considered irreversible after a critical period; however, there is potential to restore limited vision, even in adulthood. This phenomenon is particularly pronounced following complete loss of vision in the dominant eye. Adult neural cell adhesion molecule (NCAM) knockout mice have an age-related impairment of visual acuity. The underlying cause of early deterioration in visual function remains unknown. Polysialylated (PSA) NCAM is involved in different forms of neural plasticity in the adult brain, raising the possibility that NCAM plays a role in the plasticity of the visual cortex, and therefore, in visual ability. Here, we examined whether PSA-NCAM is required for visual cortical plasticity in adult C57Bl/6J mice following deafferentation and long-term monocular deprivation. Our results show that elevated PSA in the contralateral visual cortex of the reopened eye is accompanied by changes in other markers of neural plasticity: increased brain-derived neurotrophic factor (BDNF) levels and degradation of perineuronal nets (PNNs). The removal of PSA-NCAM in the visual cortex of these mice reduced BDNF expression, decreased PNN degradation, and resulted in impaired recovery of visual acuity after optic nerve transection and chronic monocular deprivation. Collectively, our results demonstrate that PSA-NCAM is necessary for the reactivation of visual cortical plasticity and recovery of visual function in adult mice. It also offers a potential molecular target for the therapeutic treatment of cortically based visual impairments.

Background The pedicled nasoseptal mucoperiosteal flap is currently widely used for the reconstruction of a skull base defect following transsphenoidal surgery. The flap is generally secured in position by a Foley catheter balloon. We describe an alternative technique using cylinders of Gelfoam™ (Pfizer Incorporated) to buttress the flap in place, obviating the need for a balloon catheter. Material and methods A review of our database identified patients who underwent endoscopic transsphenoidal surgery for a pituitary macroadenoma with nasoseptal flap, secured with small rolls of Gelfoam™ (Pfizer Incorporated) rather than a nasal Foley catheter. Minimum follow-up clinical and MRI assessments: 3 months. Results 73 patients (mean follow-up: 22 months) met the inclusion criteria: 56 non-functioning and 17 functioning pituitary adenomas. 36 patients had an intraoperative CSF leak: 30 high flow and 6 low flow leaks. The surgical repair in 35 patients included fat +/− fascia graft. One patient had a post-operative CSF leak repaired by subsequent surgery without the use of a Foley catheter. Conclusion Securing the nasoseptal flap using rolls of Gelfoam™ (Pfizer Incorporated) as described can be achieved without the use of a nasal Foley catheter.

Summary Early-onset acromegaly causing gigantism is often associated with aryl-hydrocarbon-interacting receptor protein (AIP) mutation, especially if there is a positive family history. A15y male presented with tiredness and visual problems. He was 201 cm tall with a span of 217 cm. He had typical facial features of acromegaly, elevated IGF-1, secondary hypogonadism and a large macroadenoma. His paternal aunt had a history of acromegaly presenting at the age of 35 years. Following transsphenoidal surgery, his IGF-1 normalized and clinical symptoms improved. He was found to have a novel AIP mutation destroying the stop codon c.991T>C; p.*331R. Unexpectedly, his father and paternal aunt were negative for this mutation while his mother and older sister were unaffected carriers, suggesting that his aunt represents a phenocopy. Learning points: Typical presentation for a patient with AIP mutation with excess growth and eunuchoid proportions. Unusual, previously not described AIP variant with loss of the stop codon. Phenocopy may occur in families with a disease-causing germline mutation.

Summary Early-onset acromegaly causing gigantism is often associated with aryl-hydrocarbon-interacting receptor protein (AIP) mutation, especially if there is a positive family history. A15y male presented with tiredness and visual problems. He was 201 cm tall with a span of 217 cm. He had typical facial features of acromegaly, elevated IGF-1, secondary hypogonadism and a large macroadenoma. His paternal aunt had a history of acromegaly presenting at the age of 35 years. Following transsphenoidal surgery, his IGF-1 normalized and clinical symptoms improved. He was found to have a novel AIP mutation destroying the stop codon c.991T>C; p.*331R. Unexpectedly, his father and paternal aunt were negative for this mutation while his mother and older sister were unaffected carriers, suggesting that his aunt represents a phenocopy. Learning points: Typical presentation for a patient with AIP mutation with excess growth and eunuchoid proportions. Unusual, previously not described AIP variant with loss of the stop codon. Phenocopy may occur in families with a disease-causing germline mutation.