Predicting the spatial distribution of wintering golden eagles to inform full annual cycle conservation in western North America.

Wildlife conservation strategies focused on one season or population segment may fail to adequately protect populations, especially when a species' habitat preferences vary among seasons, age-classes, geographic regions, or other factors. Conservation of golden eagles (Aquila chrysaetos) is an example of such a complex scenario, in which the distribution, habitat use, and migratory strategies of this species of conservation concern vary by age-class, reproductive status, region, and season. Nonetheless, research aimed at mapping priority use areas to inform management of golden eagles in western North America has typically focused on territory-holding adults during the breeding period, largely to the exclusion of other seasons and life-history groups. To support population-wide conservation planning across the full annual cycle for golden eagles, we developed a distribution model for individuals in a season not typically evaluated-winter-and in an area of the interior western U.S. that is a high priority for conservation of the species. We used a large GPS-telemetry dataset and library of environmental variables to develop a machine-learning model to predict spatial variation in the relative intensity of use by golden eagles during winter in Wyoming, USA, and surrounding ecoregions. Based on a rigorous series of evaluations including cross-validation, withheld and independent data, our winter-season model accurately predicted spatial variation in intensity of use by multiple age- and life-history groups of eagles not associated with nesting territories (i.e., all age classes of long-distance migrants, and resident non-adults and adult "floaters", and movements of adult territory holders and their offspring outside their breeding territories). Important predictors in the model were wind and uplift (40.2% contribution), vegetation and landcover (27.9%), topography (14%), climate and weather (9.4%), and ecoregion (8.7%). Predicted areas of high-use winter habitat had relatively low spatial overlap with nesting habitat, suggesting a conservation strategy targeting high-use areas for one season would capture as much as half and as little as one quarter of high-use areas for the other season. The majority of predicted high-use habitat (top 10% quantile) occurred on private lands (55%); lands managed by states and the Bureau of Land Management (BLM) had a lower amount (33%), but higher concentration of high-use habitat than expected for their area (1.5-1.6x). These results will enable those involved in conservation and management of golden eagles in our study region to incorporate spatial prioritization of wintering habitat into their existing regulatory processes, land-use planning tasks, and conservation actions.

Telehealth in PM&R: Past, present, and future in clinical practice and opportunities for translational research.

Telehealth refers to the use of telecommunication devices and other forms of technology to provide services outside of the traditional in-person health care delivery system. Growth in the use of telehealth creates new challenges and opportunities for implementation in clinical practice. The American Academy of Physical Medicine and Rehabilitation (AAPM&R) assembled an expert group to develop a white paper to examine telehealth innovation in Physical Medicine and Rehabilitation (PM&R). The resultant white paper summarizes how telehealth is best used in the field of PM&R while highlighting current knowledge deficits and technological limitations. The report identifies new and transformative opportunities for PM&R to advance translational research related to telehealth and enhance patient care.

Demographic partitioning of dynamic energy subsidies revealed with an Ornstein-Uhlenbeck space use model.

In populations across many taxa, a large fraction of sexually mature individuals do not breed but are attempting to enter the breeding population. Such individuals, often referred to as "floaters," can play critical roles in the dynamics and stability of these populations and buffer them through periods of high adult mortality. Floaters are difficult to study, however, so we lack data needed to understand their roles in the population ecology and conservation status of many species. Here, we analyzed satellite telemetry data with a newly developed mechanistic space use model based on an Ornstein-Uhlenbeck process to help overcome the paucity of data in studying the differential habitat selection and space use of floater and territorial golden eagles Aquila chrysaetos. Our sample consisted of 49 individuals tracked over complete breeding seasons across 4 years, totaling 104 eagle breeding seasons. Modeling these data mechanistically was required to disentangle key differences in movement and particularly to separate aspects of movement driven by resource selection from those driven by use of a central place. We found that floaters generally had more expansive space use patterns and larger home ranges, as well as evidence that they partition space with territorial individuals seemingly on fine scales through differential habitat and resource selection. Floater and territorial eagle home ranges overlapped markedly, suggesting that floaters use the interstices between territories. Furthermore, floater and territorial eagles differed in how they selected for uplift variables, key components of soaring birds' energy landscape, with territorial eagles apparently better able to find and use thermal uplift. We also found relatively low individual heterogeneity in resource selection, especially among territorial individuals, suggesting a narrow realized niche for breeding individuals, which varied from the level of among-individual variation present during migration. This work furthers our understanding of floaters' potential roles in the population ecology of territorial species and suggests that conserving landscapes occupied by territorial eagles also protects floaters.

Novel step selection analyses on energy landscapes reveal how linear features alter migrations of soaring birds.

Human modification of landscapes includes extensive addition of linear features, such as roads and transmission lines. These can alter animal movement and space use and affect the intensity of interactions among species, including predation and competition. Effects of linear features on animal movement have seen relatively little research in avian systems, despite ample evidence of their effects in mammalian systems and that some types of linear features, including both roads and transmission lines, are substantial sources of mortality. Here, we used satellite telemetry combined with step selection functions designed to explicitly incorporate the energy landscape (el-SSFs) to investigate the effects of linear features and habitat on movements and space use of a large soaring bird, the golden eagle Aquila chrysaetos, during migration. Our sample consisted of 32 adult eagles tracked for 45 spring and 39 fall migrations from 2014 to 2017. Fitted el-SSFs indicated eagles had a strong general preference for south-facing slopes, where thermal uplift develops predictably, and that these areas are likely important aspects of migratory pathways. el-SSFs also provided evidence that roads and railroads affected movement during both spring and fall migrations, but eagles selected areas near roads to a greater degree in spring compared to fall and at higher latitudes compared to lower latitudes. During spring, time spent near linear features often occurred during slower-paced or stopover movements, perhaps in part to access carrion produced by vehicle collisions. Regardless of the behavioural mechanism of selection, use of these features could expose eagles and other soaring species to elevated risk via collision with vehicles and/or transmission lines. Linear features have previously been documented to affect the ecology of terrestrial species (e.g. large mammals) by modifying individuals' movement patterns; our work shows that these effects on movement extend to avian taxa.

Author Correction: Arctic avian predators synchronise their spring migration with the northern progression of snowmelt.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Arctic avian predators synchronise their spring migration with the northern progression of snowmelt.

Migratory species display a range of migration patterns between irruptive (facultative) to regular (obligate), as a response to different predictability of resources. In the Arctic, snow directly influences resource availability. The causes and consequences of different migration patterns of migratory species as a response to the snow conditions remains however unexplored. Birds migrating to the Arctic are expected to follow the spring snowmelt to optimise their arrival time and select for snow-free areas to maximise prey encounter en-route. Based on large-scale movement data, we compared the migration patterns of three top predator species of the tundra in relation to the spatio-temporal dynamics of snow cover. The snowy owl, an irruptive migrant, the rough-legged buzzard, with an intermediary migration pattern, and the peregrine falcon as a regular migrant, all followed, as expected, the spring snowmelt during their migrations. However, the owl stayed ahead, the buzzard stayed on, and the falcon stayed behind the spatio-temporal peak in snowmelt. Although none of the species avoided snow-covered areas, they presumably used snow presence as a cue to time their arrival at their breeding grounds. We show the importance of environmental cues for species with different migration patterns.

Neurosurgical Anatomy of the Internal Carotid Artery: Magnetic Resonance Imaging Study of the Sellar Region.

BACKGROUND: Transsphenoidal surgical approaches involve dissection of the posterior wall of the sphenoid sinus in close proximity to the internal carotid arteries. To reduce the risk of vascular injury, a detailed study of embalmed cadavers' sellae was conducted and found the internal carotid artery approached within 4 mm of the midline in 10% of cases, and the closest intercarotid distance (ICD) occurred in the cavernous sinus, sphenoid sinus, and supraclinoid segments in 82%, 14%, and 4% of cases, respectively. These measurements have not previously been compared with living patients with modern imaging techniques. METHODS: This study measured the closest ICD of 233 coronal magnetic resonance imaging head scans from 183 patients (male = 88, female = 95) at the cavernous sinus, sphenoid sinus, or supraclinoid segments of the internal carotid artery. ICD at the sphenoid sinus was taken for all scans. RESULTS: The internal carotid approached within 4 mm of the midline in 1.3% of cases. The closest ICD occurred in the cavernous sinus, sphenoid sinus, and supraclinoid segments in 24.5%, 35.8%, and 39.7%, respectively. Both results were significantly different from previous cadaveric studies (chi-squared tests, P = 1.4 × 10-4 and P = 6.1 × 10-8, respectively). CONCLUSIONS: Surgically relevant measurements of the carotid arteries in the sellar are different in cadavers and living subjects. This is likely due to postmortem changes of surrounding structures. This study suggests clinically relevant anatomic studies using measurements taken from cadaveric specimens be updated with modern imaging techniques taken from living patients.

Local meteorological conditions reroute a migration.

For migrating animals, realized migration routes and timing emerge from hundreds or thousands of movement decisions made along migration routes. Local weather conditions along migration routes continually influence these decisions, and even relatively small changes in en route weather may cumulatively result in major shifts in migration patterns. Here, we analysed satellite tracking data to score a discrete navigation decision by a large migratory bird as it navigated a high-latitude, 5000 m elevation mountain range to understand how those navigational decisions changed under different weather conditions. We showed that wind conditions in particular areas along the migration pathway drove a navigational decision to reroute a migration; conditions encountered predictably resulted in migrants routing either north or south of the mountain range. With abiotic conditions continuing to change globally, simple decisions, such as the one described here, might additively emerge into new, very different migration routes.

Evaluation of alpha-II-spectrin breakdown products as potential biomarkers for early recognition and severity of aneurysmal subarachnoid hemorrhage.

This study assessed whether cytoskeletal protein alpha-II spectrin breakdown products (SBDP150, SBDP145, and SBDP120) would identify the presence of aSAH and be associated with severity (GCS score, WFNS grade and survival to hospital discharge). This prospective case-control study, conducted at a tertiary care Level I trauma center, enrolled adult patients with angiography confirmed aSAH who underwent ventriculostomy placement for cerebrospinal fluid (CSF) drainage. There were 40 patients enrolled in the study, 20 with aSAH and 20 control subjects. Patients with aSAH were a mean age of 54 (SD15) and 75% were female. There were significant differences in SBDP150, SBDP145, and SBDP120 CSF levels between patients with and without aSAH (p < 0.001), even in those presenting with a GCS Score of 15 and a WFNS Grade 1. The AUC for distinguishing aSAH from control subjects was 1.0 for SBDP150 and SBDP145, and 0.95 for SBDP120. SBDP150 and SBDP145 both yielded sensitivities and specificities of 100% and SBDP120 was 90% and 100% respectively. Moreover, there were significantly higher levels of SBDP150 and SBDP145 in the non-survivors than in the survivors (p < 0.001). This study demonstrates the potential that SBDP's have as biomarkers for recognition and severity of aSAH. A larger prospective study is warranted.

Intraspecific evolutionary relationships among peregrine falcons in western North American high latitudes.

Subspecies relationships within the peregrine falcon (Falco peregrinus) have been long debated because of the polytypic nature of melanin-based plumage characteristics used in subspecies designations and potential differentiation of local subpopulations due to philopatry. In North America, understanding the evolutionary relationships among subspecies may have been further complicated by the introduction of captive bred peregrines originating from non-native stock, as part of recovery efforts associated with mid 20th century population declines resulting from organochloride pollution. Alaska hosts all three nominal subspecies of North American peregrine falcons-F. p. tundrius, anatum, and pealei-for which distributions in Alaska are broadly associated with nesting locales within Arctic, boreal, and south coastal maritime habitats, respectively. Unlike elsewhere, populations of peregrine falcon in Alaska were not augmented by captive-bred birds during the late 20th century recovery efforts. Population genetic differentiation analyses of peregrine populations in Alaska, based on sequence data from the mitochondrial DNA control region and fragment data from microsatellite loci, failed to uncover genetic distinction between populations of peregrines occupying Arctic and boreal Alaskan locales. However, the maritime subspecies, pealei, was genetically differentiated from Arctic and boreal populations, and substructured into eastern and western populations. Levels of interpopulational gene flow between anatum and tundrius were generally higher than between pealei and either anatum or tundrius. Estimates based on both marker types revealed gene flow between augmented Canadian populations and unaugmented Alaskan populations. While we make no attempt at formal taxonomic revision, our data suggest that peregrine falcons occupying habitats in Alaska and the North Pacific coast of North America belong to two distinct regional groupings-a coastal grouping (pealei) and a boreal/Arctic grouping (currently anatum and tundrius)-each comprised of discrete populations that are variously intra-regionally connected.

To migrate, stay put, or wander? Varied movement strategies in bald eagles (Haliaeetus leucocephalus).

BACKGROUND: Quantifying individual variability in movement behavior is critical to understanding population-level patterns in animals. Here, we explore intraspecific variation in movement strategies of bald eagles (Haliaeetus leucocephalus) in the north Pacific, where there is high spatiotemporal resource variability. We tracked 28 bald eagles (five immature, 23 adult) using GPS transmitters between May 2010 and January 2016. RESULTS: We found evidence of four movement strategies among bald eagles in southeastern Alaska and western Canada: breeding individuals that were largely sedentary and remained near nest sites year-round, non-breeding migratory individuals that made regular seasonal travel between northern summer and southern winter ranges, non-breeding localized individuals that displayed fidelity to foraging sites, and non-breeding nomadic individuals with irregular movement. On average, males traveled farther per day than females. Most nomadic individuals were immature, and all residential individuals (i.e. breeders and localized birds) were adults. CONCLUSIONS: Alternative movement strategies among north Pacific eagles are likely associated with the age and sex class, as well as breeding status, of an individual. Intraspecific variation in movement strategies within the population results in different space use patterns among contingents, which has important implications for conservation and management.

Bilateral internal auditory canal gangliogliomas mimicking neurofibromatosis Type II.

BACKGROUND: Gangliogliomas are rare low grade, typically well-differentiated, tumors that are composed of mature ganglion cells and neoplastic glial cells. These tumors can appear at virtually any location along the neuroaxis but classically occur in the temporal lobe of young patients. In a small number of cases, gangliogliomas have presented as masses in the brainstem or involving cranial nerves. With the exception of vestibular schwannomas, bilateral tumors in the region of the internal auditory canal (IAC) or cerebellopontine angle (CPA) are exceedingly rare. CASE DESCRIPTION: We report a case of a 58-year-old male who presented with hearing loss, tinnitus, and vertigo. Initial magnetic resonance imaging revealed bilateral nonenhancing IAC/CPA tumors. Based on this finding, a presumptive diagnosis of neurofibromatosis Type II was made, which was initially managed conservatively with close observation. He returned for follow-up with worsening vertigo and tinnitus, thus prompting the decision to proceed with surgical resection of the symptomatic mass. Intriguingly, pathological study demonstrated a WHO Grade I ganglioglioma. DESCRIPTION: We report a case of a 58-year-old male who presented with hearing loss, tinnitus, and vertigo. Initial magnetic resonance imaging revealed bilateral nonenhancing IAC/CPA tumors. Based on this finding, a presumptive diagnosis of neurofibromatosis Type II was made, which was initially managed conservatively with close observation. He returned for follow-up with worsening vertigo and tinnitus, thus prompting the decision to proceed with surgical resection of the symptomatic mass. Intriguingly, pathological study demonstrated a WHO Grade I ganglioglioma. CONCLUSION: This is the first reported case of bilateral IAC/CPA gangliogliomas. When evaluating bilateral IAC/CPA lesions with unusual imaging characteristics, ganglioglioma should be included in the differential diagnosis.

En Bloc Resection of Desmoplastic Neurotropic Melanoma with Perineural Invasion of the Intracranial Trigeminal and Intraparotid Facial Nerve: Case Report and Review of the Literature.

Background Desmoplastic neurotropic melanoma (DNM) is a rare, highly malignant, and locally invasive form of cutaneous melanoma with a tendency for perineural invasion (PNI). Methods We report a case of a 61-year-old man presenting with right-sided trigeminal neuralgia and progressive facial paresis due to the PNI of the intracranial trigeminal nerve and the intraparotid facial nerve from DNM. We also present a review of the literature with six cases of DNM with PNI of the intracranial trigeminal nerve identified. Results The combined transtemporal-infratemporal fossa approach was performed to achieve total en bloc resection of the tumor mass followed by postoperative radiotherapy (PORT). After 24 months of follow-up, the patient remains disease free with no signs of recurrence on magnetic resonance imaging. Conclusion We recommend the en bloc resection of the tumor mass followed by PORT for the management of DNM with PNI. A high index of suspicion for PNI as a cause of cranial neuropathies is essential for the early detection and treatment of patients with known melanoma.

Concomitant intracranial pressure monitoring during venous sinus stenting for intracranial hypertension secondary to venous sinus stenosis.

BACKGROUND: There is a growing body of literature supporting venous sinus stenosis as a causative etiology for many patients diagnosed with idiopathic intracranial hypertension. Recent series have documented improvement in the pre- and post-stenosis venous pressure gradient as well as clinical symptoms after stenting. Concomitant real time intracranial pressure (ICP) monitoring has not been previously described during venous sinus stenting. CASE REPORT: A woman in her twenties presented with rapidly progressive visual loss and cranial neuropathies with an MRI revealing high grade right transverse sinus stenosis. Lumbar puncture demonstrated an opening pressure >55 cm H2O. Her vision and cranial neuropathies continued to worsen despite ventriculoperitoneal shunting. A parenchymal ICP monitoring wire was placed, revealing ICP persistently >70 cm H2O. She underwent venography and a pre- to post-stenosis pressure gradient of 55 mm Hg was measured. The patient underwent sinus stenting resulting in a near immediate reduction in her ICP from 70 to 20 cm H2O within 30 s after deployment. Her ICP completely normalized within 24 h of stenting. CONCLUSIONS: A case is presented of severe intracranial hypertension with rapidly progressive neurologic decline despite CSF diversion secondary to venous sinus stenosis that resolved following venous sinus stenting. This is the first report of real time ICP monitoring during venous sinus stenting.

Resection of a pontine cavernous malformation via an endoscopic endonasal approach: a case report.

BACKGROUND AND IMPORTANCE: Cavernous malformations of the brainstem are a dilemma in terms of deciding when to operate, and they remain difficult to access surgically. We present a novel approach for the resection of a brainstem cavernous malformation. CLINICAL PRESENTATION: A 59-year-old woman presented with a 1-month history of intermittent dysarthria, right facial weakness, and left arm and leg weakness. A magnetic resonance image revealed a 2-cm mass in the pons with blood products of differing ages, consistent with a cavernous malformation. We discussed with her the risks of surgical resection and conservative management. She decided to pursue conservative management. Two weeks later, she returned to the emergency room with diplopia and left-sided hemiplegia. Acute hemorrhage within the right pons was seen. She then chose to undergo surgical resection. CONCLUSION: The patient underwent an endoscopic transnasal approach for resection of a pontine cavernous malformation. Image guidance was used to identify key anatomic landmarks. A gross total resection was achieved without new neurological deficits. With physical and occupational therapy, the patient developed antigravity strength in her left upper and lower extremities before discharge. At her 4-week follow-up, she was ambulating independently with the assistance of a cane. We report the successful gross total resection of a pontine cavernous malformation via an endoscopic transnasal approach. This patient had improvement in neurological symptoms after surgical resection with minimal surgical morbidity. Technologic advances in endoscopic skull base approaches have provided access to lesions of the skull base previously requiring more invasive approaches.

Results of the prospective, randomized, multicenter clinical trial evaluating a biosynthesized cellulose graft for repair of dural defects.

BACKGROUND: After intradural cranial surgery, a dural substitute is often required for dural closure. Although preferred, limitations of autograft include local availability and additional surgical site morbidity. Thus, allografts, xenografts, and synthetics are frequently used. OBJECTIVE: To report 6-month results of a randomized, controlled trial of a biosynthesized cellulose (BSC) composed duraplasty device compared with commercially available dural replacements. METHODS: A total of 99 patients (62 BSC; 37 control) were treated on protocol, using a 2:1 (BSC:control) blocked randomization schedule. Physical examinations were performed pre- and postoperatively within 10 days and at 1, 3, and 6 months. Magnetic resonance imaging was performed preoperatively and at 6 months. The primary study endpoint was the absence of pseudomeningocele and extracerebral fluid collection confirmed radiographically and the absence of cerebrospinal fluid fistula at 6 months. RESULTS: At 6 months, the primary hypothesis, noninferiority of the BSC implant compared with the control group, was confirmed (P = .0206). Overall success was achieved by 96.6% of BSC and 97.1% of control patients. No significant difference was revealed between treatment groups for surgical site infection (P = 1.0000) or wound healing assessment (P ≥ .3685) outcomes, or radiologic endpoints (P ≥ .4061). Device strength and seal quality favored BSC. CONCLUSION: This randomized, controlled trial establishes BSC as noninferior to commercially available dural replacement devices. BSC offers a hypothetical advantage concerning prion and other infectious agent exposure; superior handling qualities are evident. Longer term data are necessary to identify limitations of BSC and its potential equivalence to the gold standard of pericranium.

Identification and preliminary characterization of ubiquitin C terminal hydrolase 1 (UCHL1) as a biomarker of neuronal loss in aneurysmal subarachnoid hemorrhage.

By using two different approaches, ubiquitin C-terminal hydrolase 1 (UCHL1) was identified as a potential cerebrospinal fluid (CSF) biomarker of neuronal loss in aneurysmal subarachnoid hemorrhage (ASAH) and presumably other CNS damage and disease states. Appropriate antibodies and a sensitive ELISA were generated, and the release of UCHL1 into CSF was compared with that of pNF-H and S100beta in a cohort of 30 ASAH patients. Both UCHL1 and pNF-H showed persistent release into CSF in almost all patients in the second week postaneurysmal rupture (AR), and S100beta levels rapidly declined to baseline levels in 23 of 30 patients. Seven of thirty patients showed persistently elevated S100beta levels over the first 5 days post-AR and also had relatively higher levels of pNF-H and UCHL1 higher compared with the rest. These patients proved to have very poor outcomes, with 6 of 7 expiring. Patients who did reduce S100beta levels tended to have a better outcome if pNF-H and UCHL1 levels were also lower, and elevated UCHL1 levels in the second week post-AR were particularly predictive of poor outcome. Acute coordinated releases of large amounts of UCHL1, pNF-H, and S100beta in 16 of 30 patients were observed, suggesting sudden loss of brain tissues associated with secondary events. We conclude that measurement of the CSF levels of these proteins reveals details of ASAH progression and recovery and predicts patient outcome.

The effect of coiling versus clipping of ruptured and unruptured cerebral aneurysms on length of stay, hospital cost, hospital reimbursement, and surgeon reimbursement at the university of Florida.

OBJECTIVE: There are few studies comparing the economic costs and reimbursements for aneurysm clipping versus coiling, and none are from the United States. Our hypothesis predicted that coiling would result in shorter lengths of hospitalization than clipping in patients with unruptured aneurysms and would therefore result in lower hospital charges. However, because of the severity of subarachnoid hemorrhage, there would be no difference in length of hospitalization or hospital charges in patients with ruptured aneurysms. METHODS: We compared aneurysm coiling with aneurysm clipping in patients with unruptured and ruptured aneurysms treated at the University of Florida from January 2005 to June 2007 for differences in length of hospitalization, hospital costs, hospital collections, and surgeon collections. Patient demographic and aneurysm characteristic data were obtained from a clinical database. Length of hospitalization, cost, billing, and collection data were obtained from the hospital cost accounting database. Multivariate statistical analyses of length of hospitalization, hospital costs, hospital collections, and surgeon collections were performed using factors including patient age, sex, aneurysm size, aneurysm location, aneurysm treatment, presence of subarachnoid hemorrhage, clinical grade, payor, hospital billing, and surgeon billing. RESULTS: There were 565 patients with cerebral aneurysms treated either surgically (306 patients, 54%) or endovascularly (259 patients, 46%). In patients without subarachnoid hemorrhage (unruptured aneurysms) (n = 367), surgery, compared with endovascular treatment, was associated with longer hospitalization (P < 0.001), but lower hospital costs (P < 0.001), higher surgeon collections (P = 0.003), and similar hospital collections. In patients with subarachnoid hemorrhage (ruptured aneurysms) (n = 198), surgery was associated with lower hospital costs (P = 0.011), but similar length of stay, surgeon collections, and hospital collections. Larger aneurysm size was significantly associated with longer hospitalization in the patients with unruptured aneurysms (P < 0.001) and higher hospital costs for both patients with unruptured (P < 0.001) and ruptured (P = 0.015) aneurysms. The payor was significantly associated with hospital costs in patients with ruptured aneurysms (P = 0.034) and length of stay (unruptured aneurysms, P < 0.001; ruptured aneurysms, P < 0.001), hospital collections (unruptured aneurysms, P < 0.001; ruptured aneurysms, P < 0.001), and surgeon collections (unruptured aneurysms, P < 0.001; ruptured aneurysms, P < 0.001) in both patients with unruptured and ruptured aneurysms. A worse clinical grade was significantly associated with higher hospital costs (P < 0.001). CONCLUSION: Despite a shorter length of hospitalization in patients with unruptured aneurysms, coiling was associated with higher hospital costs in both patients with unruptured and ruptured aneurysms. This is likely attributable to the higher device cost of coils than clips. The advantages of coiling over clipping would be better realized if the cost of coils could be comparably reduced to that of clips.

alphaII-Spectrin breakdown product cerebrospinal fluid exposure metrics suggest differences in cellular injury mechanisms after severe traumatic brain injury.

Traumatic brain injury (TBI) produces alphaII-spectrin breakdown products (SBDPs) that are potential biomarkers for TBI. To further understand these biomarkers, the present study examined (1) the exposure and kinetic characteristics of SBDPs in cerebrospinal fluid (CSF) of adults with severe TBI, and (2) the relationship between these exposure and kinetic metrics and severity of injury. This clinical database study analyzed CSF concentrations of 150-, 145-, and 120-kDa SBDPs in 38 severe TBI patients. Area under the curve (AUC), mean residence time (MRT), maximum concentration (C(max)), time to maximum concentration (T(max)), and half-life (t(1/2)) were determined for each SBDP. Markers of calpain proteolysis (SBDP150 and SBDP145) had a greater median AUC and C(max) and a shorter MRT than SBDP120, produced by caspase-3 proteolysis in the CSF in TBI patients ( p < 0.001). AUC and MRT for SBDP150 and SBDP15 were significantly greater in patients with worse Glasgow Coma Scale (GCS) scores at 24 h after injury compared to those whose GCS scores improved (AUC p=0.013, MRT p=0.001; AUC p=0.009, MRT p=0.021, respectively). A positive correlation was found between patients with longer elevations in intracranial pressure (ICP) measurements of 25mmHg or higher and those with a greater AUC and MRT for all three biomarkers. This is the first study to show that the biomarkers of proteolysis differentially associated with calpain and caspase-3 activity have distinct CSF exposure profiles following TBI that suggest a prominent role for calpain activity. Further studies are being conducted to determine if exposure and kinetic metrics for biofluid-based biomarkers can predict clinical outcome.

Comparison of N-butyl cyanoacrylate and onyx for the embolization of intracranial arteriovenous malformations: analysis of fluoroscopy and procedure times.

OBJECTIVE: Intracranial arteriovenous malformations (AVM) may be managed through staged preoperative embolization and resection. Two commonly used liquid embolics are N-butyl cyanoacrylate (nBCA; Cordis Microvascular, Inc., New Brunswick, NJ) and Onyx (ev3, Inc., Irvine, CA). We sought to compare the utility of these agents in terms of fluoroscopy and procedure times. METHODS: All intracranial AVMs embolized from 2002 to 2006 at the University of Florida were included in this study. Patients were stratified into three treatment groups: nBCA, Onyx, and patients who received both nBCA and Onyx during separate embolizations. Cohorts were compared by sex, age, Spetzler-Martin grade, AVM volume, fluoroscopy time, procedure time, surgical blood loss, and complications. RESULTS: A total of 182 embolizations were performed on 88 patients (nBCA, 60 patients and 106 procedures; Onyx, 20 patients and 43 procedures; and nBCA/Onyx, eight patients and 16 nBCA and 17 Onyx procedures). There were no significant differences in patient demographics, AVM volumes, and Spetzler-Martin grades. Mean fluoroscopy and procedure times were increased for Onyx (57 min; 2.6 h) compared with nBCA (37 min; 2.1 h) embolizations (P < 0.0001 and P = 0.001, respectively). Cumulative mean fluoroscopy time was increased for Onyx (135 min) and nBCA/Onyx (180 min) cohorts relative to nBCA (64 min; P < 0.0001). Cumulative mean procedure time was increased in the nBCA/Onyx group (10.4 h) compared with nBCA (3.7 h) and Onyx (5.4 h; P < 0.0001). Seventy patients (80%) underwent AVM resection. No significant differences in surgical blood loss or complication rates were observed among the cohorts. CONCLUSION: Onyx AVM embolization requires increased fluoroscopy and procedure times compared with nBCA. Further investigation is necessary to justify increased radiation exposure and procedure time associated with Onyx.