Comparative anatomy of the caudate nucleus in canids and felids: Associations with brain size, curvature, cross-sectional properties, and behavioral ecology.

The evolutionary history of canids and felids is marked by a deep time separation that has uniquely shaped their behavior and phenotype toward refined predatory abilities. The caudate nucleus is a subcortical brain structure associated with both motor control and cognitive, emotional, and executive functions. We used a combination of three-dimensional imaging, allometric scaling, and structural analyses to compare the size and shape characteristics of the caudate nucleus. The sample consisted of MRI scan data obtained from six canid species (Canis lupus lupus, Canis latrans, Chrysocyon brachyurus, Lycaon pictus, Vulpes vulpes, Vulpes zerda), two canid subspecies (Canis lupus familiaris, Canis lupus dingo), as well as three felids (Panthera tigris, Panthera uncia, Felis silvestris catus). Results revealed marked conservation in the scaling and shape attributes of the caudate nucleus across species, with only slight deviations. We hypothesize that observed differences in caudate nucleus size and structure for the domestic canids are reflective of enhanced cognitive and emotional pathways that possibly emerged during domestication.

Transvenous embolization of noncavernous dural arteriovenous fistulas (dAVFs): A systematic review and meta-analysis.

BACKGROUND: Intracranial dural arteriovenous fistulas (dAVFs) are abnormal connections between arteries and veins within the dura mater. Various treatment modalities, such as surgical ligation, endovascular intervention, and radiosurgery, aim to close the fistulous connection. Although transvenous embolization (TVE) is the preferred method for carotid-cavernous fistulas, its description and outcomes for noncavernous dAVFs vary. This has prompted a systematic review and meta-analysis to comprehensively assess the effectiveness of TVE in treating noncavernous dAVFs, addressing variations in outcomes and techniques. METHODS: We searched PubMed and Embase, spanning from the earliest records to December 2022, to identify pertinent English-language articles detailing the utilization of TVE. We focused on specific procedural details, outcomes, and complications in patients older than 18 years. The data collected and analyzed comprised the sample size, number of fistulas, publication specifics, presenting symptoms, fistula grades, and pooled rates of embolizations, outcomes, follow-up information, and complications. RESULTS: From a total of 565 screened articles, 15 retrospective articles encompassing 166 patients spanning across seven countries met the inclusion criteria. Their Newcastle-Ottawa scores ranged from 6 to 8. Intraprocedural complication rate was 10% (95% confidence interval [CI] = 5.9-17.1) and in-hospital postprocedural complication rate was 5.4% (95% CI = 2.8-10.6). Prevalence of in-hospital mortality was 5.5% (95% CI = 2.9-10.6). Complication rate during follow-up was 8.6% (95% CI = 4.7-15.7) with fistula rupture occurring in 5.5% (95% CI = 2.6-11.6) of patients. Complete obliteration rate at final angiographic follow-up was 94.9% (95% CI = 90.3-99.9). Symptoms improved in 95% (95% CI = 89.8-100) of patients at final follow-up. CONCLUSION: To our knowledge, we present the first meta-analysis assessing obliteration rates, outcomes, and complications of TVE for dAVFs. Our analysis highlights the higher (>90%) complete obliteration rates. Large prospective multicenter studies are needed to better define the utility of TVE for noncavernous dAVFs.

Microinstrumentation for Brain Organoids.

Brain organoids are three-dimensional aggregates of self-organized differentiated stem cells that mimic the structure and function of human brain regions. Organoids bridge the gaps between conventional drug screening models such as planar mammalian cell culture, animal studies, and clinical trials. They can revolutionize the fields of developmental biology, neuroscience, toxicology, and computer engineering. Conventional microinstrumentation for conventional cellular engineering, such as planar microfluidic chips; microelectrode arrays (MEAs); and optical, magnetic, and acoustic techniques, has limitations when applied to three-dimensional (3D) organoids, primarily due to their limits with inherently two-dimensional geometry and interfacing. Hence, there is an urgent need to develop new instrumentation compatible with live cell culture techniques and with scalable 3D formats relevant to organoids. This review discusses conventional planar approaches and emerging 3D microinstrumentation necessary for advanced organoid-machine interfaces. Specifically, this article surveys recently developed microinstrumentation, including 3D printed and curved microfluidics, 3D and fast-scan optical techniques, buckling and self-folding MEAs, 3D interfaces for electrochemical measurements, and 3D spatially controllable magnetic and acoustic technologies relevant to two-way information transfer with brain organoids. This article highlights key challenges that must be addressed for robust organoid culture and reliable 3D spatiotemporal information transfer.

Neutrophils: Novel Contributors to Estrogen-Dependent Intracranial Aneurysm Rupture Via Neutrophil Extracellular Traps.

Background Intracranial aneurysms (IAs) are more prevalent in women than men, and aneurysmal subarachnoid hemorrhage disproportionately affects postmenopausal women. These sex differences suggest estrogen protects against IA progression that can lead to rupture, but the underlying mechanisms are not fully understood. Although studies have demonstrated estrogen regulates inflammatory processes that contribute to IA pathogenesis, the role of neutrophils remains to be characterized. Using a murine model, we tested our hypothesis that neutrophils contribute to IA pathophysiology in an estrogen-dependent manner. Methods and Results We compared neutrophil infiltration in C57BL/6 female mice that develop IAs to those with a normal circle of Willis. Next, we investigated the estrogen-dependent role of neutrophils in IA formation, rupture, and symptom-free survival using a neutrophil depletion antibody. Finally, we studied the role of neutrophil extracellular trap formation (NETosis) as an underlying mechanism of aneurysm progression. Mice that developed aneurysms had increased neutrophil infiltration compared with those with a normal circle of Willis. In estrogen-deficient female mice, both neutrophil depletion and NETosis inhibition decreased aneurysm rupture. In estrogen-deficient female mice treated with estrogen rescue and estrogen-intact female mice, neither neutrophil depletion nor NETosis inhibition affected IA formation, rupture, or symptom-free survival. Conclusions Neutrophils contribute to aneurysm rupture in an estrogen-dependent manner. NETosis appears to be an underlying mechanism for neutrophil-mediated IA rupture in estrogen deficiency. Targeting NETosis may lead to the development of novel therapeutics to protect against IA rupture in the setting of estrogen deficiency.

Enhanced Approaches to the Treatment of Distal Radius Fractures.

Distal radius fractures are among the most common fractures treated by orthopedic surgeons. Various classification systems have been described which can help in deciding the approach for fixation. In some cases, a computed tomography scan can provide better understanding of the fracture fragments and displacement for surgical planning. Plating through the volar approach is the most common approach for fractures meeting operative criteria. Several additional approaches can be used for specific fracture patterns. These approaches can be used in isolation or in conjunction with other approaches to aid in visualization and fixation.

EUS-Guided Vascular Interventions.

Endoscopic ultrasound (EUS) has numerous advanced applications as a diagnostic and therapeutic modality in contemporary medicine. Through intraluminal placement, EUS offers a real-time Doppler-guided endoscopic visualization and access to intra-abdominal vasculature, which were previously inaccessible using historical methods. We aim to provide a comprehensive review of key studies on both current and future EUS-guided vascular applications. This review details EUS-based vascular diagnostic techniques of portal pressure measurements in the prognostication of liver disease and portal venous sampling for obtaining circulating tumor cells in the diagnosis of cancer. From an interventional perspective, we describe effective EUS-guided treatments via coiling and cyanoacrylate injections of gastric varices and visceral artery pseudoaneurysms. Specific attention is given to clinical studies on efficacy and procedural techniques described by investigators for each EUS-based application. We explore novel and future emerging EUS-based interventions, such as liver tumor ablation and intrahepatic portosystemic shunt placement.

Chronic opioid users with dysphagia are indistinguishable from symptomatic nonusers on functional lumen imaging probe evaluation.

BACKGROUND: Opioid-induced esophageal dysmotility (OIED) includes spastic esophageal motility disorders, increasingly recognized in the contemporary opioid epidemic. We assessed functional lumen imaging probe (FLIP) findings in diagnosing OIED. METHODS: Symptomatic patients undergoing FLIP with no prior foregut surgery who completed validated questionnaires were identified and segregated into chronic opioid users and nonusers in this cohort study. Esophagogastric junction (EGJ) distensibility index (DI), EGJ diameter, and esophageal body contraction patterns were extracted. Symptom profiles were compared to FLIP findings between chronic opioid users and nonusers. Outcome was evaluated in a subset using the same validated questionnaires. RESULTS: Over the 18-months study period, of 116 patients (median age 62 years, 70.7% female), 33 (28.4%) were chronic opioid users, with median morphine milligram equivalent of 30 mg. While presenting symptoms were similar, chronic opioid users reported higher perceptive symptoms (p = 0.008) and worse quality of life (p = 0.01) compared to nonusers. Median DI trended lower in chronic opioid users (p = 0.08), with more retrograde repetitive contractions (p < 0.001) and less absent contractility (p = 0.007), but final FLIP diagnoses were similar compared to nonusers. There was no correlation between opioid dose and FLIP metrics. In the subset with follow-up, perceptive symptoms trended higher in chronic opioid users (p = 0.08), but symptom improvement following therapy was similar in both groups. CONCLUSIONS & INFERENCES: Symptomatic chronic opioid users have FLIP diagnoses that are similar to nonusers, despite higher perceptive symptoms and worse quality of life. Dominant symptoms improve both in chronic opioid users and nonusers following treatment directed by FLIP.

Traumatic Brain Injury and Secondary Neurodegenerative Disease.

Traumatic brain injury (TBI) is a devastating event with severe long-term complications. TBI and its sequelae are one of the leading causes of death and disability in those under 50 years old. The full extent of secondary brain injury is still being intensely investigated; however, it is now clear that neurotrauma can incite chronic neurodegenerative processes. Chronic traumatic encephalopathy, Parkinson's disease, and many other neurodegenerative syndromes have all been associated with a history of traumatic brain injury. The complex nature of these pathologies can make clinical assessment, diagnosis, and treatment challenging. The goal of this review is to provide a concise appraisal of the literature with focus on emerging strategies to improve clinical outcomes. First, we review the pathways involved in the pathogenesis of neurotrauma-related neurodegeneration and discuss the clinical implications of this rapidly evolving field. Next, because clinical evaluation and neuroimaging are essential to the diagnosis and management of neurodegenerative diseases, we analyze the clinical investigations that are transforming these areas of research. Finally, we briefly review some of the preclinical therapies that have shown the most promise in improving outcomes after neurotrauma.

Characterization of the Epidemiology and Risk Factors for Hand Fractures in Patients Aged 1 to 19 Presenting to United States Emergency Departments: A Retrospective Study of 21,031 Cases.

BACKGROUND: Hand fractures are among the most common injuries presenting in pediatric emergency departments (EDs) with incidence reported as high as 624 hand fractures per 100,000 person-years. If gone untreated, these injuries can lead to pain, loss of function, and psychological trauma. The purpose of this study was to identify risk factors and characterize pediatric hand fractures over a 5-year period. METHODS: The National Electronic Injury Surveillance System (NEISS) was queried for all hand fractures in patients aged 1 to 19 years presenting to US EDs between 2016 and 2020. Incidence was calculated using US census data. Cases were retrospectively analyzed using age, location of the injury, sex, coronavirus disease-2019 (COVID-19) era, and etiology of injury. Bivariate logistic regression was used where appropriate. RESULTS: A total of 21,031 pediatric hand fractures were identified, representing an estimated 565,833 pediatric hand fractures presenting to EDs between 2016 and 2020. The mean incidence of pediatric hand fractures was 138.3 fractures for 100,000 person-years [95% confidence interval (CI): 136.2-140.4], with a 39.2% decrease in incidence occurring between 2019 and 2020. It was found that 42.2% of the fractures were in patients aged 10 to 14. The incidence of hand fractures for males and females was 97.9 (95% CI: 96.2-99.7) and 40.4 (95% CI: 39.2-41.5), respectively, with the male rate peaking at age 14 and the female rate peaking at age 12. Age, sex, location of the injury, and injury during the COVID-19 pandemic were demonstrated to influence the frequency and etiology of the fracture. CONCLUSION: This study determined the incidence of pediatric hand fractures presenting to EDs across the United States. In addition, it identified risk factors for common hand fracture etiologies (sports-related, falling, crush, punching) and demonstrated the change in rates of different etiologies of pediatric hand fractures that presented to US EDs during the COVID-19 pandemic. LEVEL OF EVIDENCE: Level III-retrospective comparative study.

Performance After Concussion in National Basketball Association Players.

Background: Concussions have received national attention in collision sports such as football, soccer, and hockey, but less focus has been placed on basketball. Purpose: To determine return-to-play (RTP) and player performance in the first and second season after concussion in National Basketball Association (NBA) players. Study Design: Descriptive epidemiology study. Methods: An online database of publicly available NBA athlete injuries was queried for instances of "concussion" between 2010 and 2018. The age at injury, team, position, height, weight, body mass index, NBA experience, date of concussion, date of return, and seasons played postconcussion was recorded for each player. Regular-season statistics (games started, games played, minutes played, and player efficiency rating [PER]) were compiled for the season before, and 2 seasons immediately after, injury. Kaplan-Meier survivorship plots were computed for athlete RTP and retirement endpoints. Results: A total of 81 injuries were identified from 2010 to 2018, with a rate of 2.0 concussions per 100 player-years. Overall RTP was 100% after concussion, with nearly all (88%) returning in the season of injury; 12% of players experienced a season-ending concussion. RTP averaged 37.3 days after injury, varying widely (range, 2-291 days). Compared with preinjury season (78.0%), athletes played in significantly fewer overall games in the season of injury (36.6%; P < .0001), as well as 1 (69.5%; P = .0229) and 2 seasons postinjury (73.2%; P = .3192). PER scores were not significantly different across the study period. Each point increase in a player's preinjury PER score was associated with a 2.4% decrease in PER from the preinjury season to season of injury (P = .0016) and a 3.1% decrease from preinjury to season after injury (P = .0053). Each increasing year of age or year of experience was associated with 5% decline in PER score at 1 season after injury. Conclusion: NBA players had a high RTP after concussion, with most returning in the same season as the injury. Players sustaining concussions played significantly fewer games for at least 2 seasons after injury. Performance via PER did not change across the entire cohort; however, players with higher preinjury PER, and older players were more likely to sustain a greater decline in performance after injury.

Supination Adduction Vertical Medial Malleolar Fracture Fixation with Buttress Plating vs a Novel Screw-Only Construct: A Cadaveric Biomechanical Study.

BACKGROUND: Supination adduction ankle fractures are unique among rotational ankle fractures as plate constructs are more commonly used than independent screws for medial malleolar fixation. The purpose of this study was to compare fracture displacement between plate fixation to a novel screw-only construct using a cadaveric biomechanical early-weightbearing model for the treatment of vertical medial malleolus fractures. METHODS: Six nonosteoporotic fresh-frozen cadaver shanks and feet in matched pairs underwent a vertical osteotomy of the medial malleolus to simulate the supination adduction type injury. Osteoporosis was measured using DEXA scans. One specimen from each pair was fixed with a one-third tubular buttress plate and the other with screw-only fixation. The specimens were then axially loaded for 100 000 cycles to simulate protected weightbearing, and subsequently loaded to failure in supination. Stiffness, fracture displacement, and load to failure were recorded. Statistical significance was set at P <.05. RESULTS: There were no measurable differences in displacement between the 2 constructs during axial cyclic loading after 100 000 cycles (plate, 0.74 ± 0.09 mm; screws, 0.79 ± 0.18 mm; P = .225). During supination and axial load to failure, the plate outperformed the screw construct. For load to failure (2 mm displacement) at the fracture site, the plate group failed at 716 ± 240 N, whereas the screw group failed at 567 ± 237 N (P = .015). During load to catastrophic failure, the plate group outperformed the screw group (plate, 6011 ± 1646 N; screws, 4578 ± 1837 N; P = .002). CONCLUSION: For vertical medial malleolar fractures, the screw-only construct demonstrated no statistical difference when compared to buttress plating for cyclical axial loading, simulating early weightbearing in a boot. However, buttress plating is 21% to 24% stronger than the screw-only fixation construct in overall strength and prevention of catastrophic failure when loading in a supinated position. CLINICAL RELEVANCE: The screw-only construct is biomechanically similar to a buttress plate when simulating early protected weightbearing. This suggests that early weightbearing as tolerated in a controlled ankle motion boot beginning 2 weeks postoperatively is mechanically safe for this fracture pattern and does not result in unacceptable amounts of fracture displacement. This construct may be useful as a less invasive treatment modality for the treatment of vertical medial malleolus fractures in select patients.

Pentobarbital Coma Use in a Pregnant Patient With Refractory Intracranial Hypertension: A Case Report.

OBJECTIVE: Intracranial hypertension is a life-threatening condition that requires emergent diagnosis and management. Although pentobarbital coma for refractory intracranial hypertension has been studied in the general population, this study is the first reported case of pentobarbital coma use in a pregnant patient. METHODS: We performed a retrospective chart review of a pregnant patient with refractory intracranial hypertension and reviewed the current literature on the role of pentobarbital coma. RESULTS: We present the case of a 35-year-old woman at 26 weeks of gestation who developed refractory intracranial hypertension secondary to rupture of a dural arteriovenous fistula. The patient was taken to surgery for decompressive hemicraniectomy, clot evacuation, and dural arteriovenous fistula resection. Subsequently, the patient was treated with pentobarbital coma for 5 days and achieved adequate control of her intracranial pressures. The patient and fetus were closely monitored by the obstetrics team with no apparent harm to fetal well-being during her hospital stay. The patient underwent planned cesarean delivery at term, and both the mother and newborn were discharged in stable condition with no known pentobarbital-related complications. CONCLUSIONS: Thus, we present the first case report demonstrating that pentobarbital coma may be a safe and efficacious option for treating pregnant patients with life-threatening refractory intracranial hypertension. We also provide dosing information for pentobarbital administration. Additional studies and reports involving pregnant patients are needed to better understand the impact of pentobarbital on both the mother and fetus. Furthermore, long-term follow-up of both the mother and newborn is critical to identifying any delayed sequelae of neonatal exposure to pentobarbital.

Spinal cord injury and neurogenic lower urinary tract dysfunction: what do we know and where are we going?

One of the well reported but difficult to manage symptoms of spinal cord injury (SCI) is neurogenic lower urinary tract dysfunction (NLUTD). The type of NLUTD is variable based on location and extent of injury. SCI affects more males and NLUTD is especially debilitating for men with incomplete injury. This review summarizes the anatomical basis of NLUTD in SCI and discusses current diagnostic and management strategies that are being utilized clinically. The last two sections address new innovations and emerging discoveries with the goal of increasing scientific interest in improving treatment options for people with SCI. Areas warranting further investigation are pinpointed to address current gaps in knowledge and/or appropriate technology.

A retrospective cohort study of risk factors and outcomes in older patients admitted to an inner-city geriatric unit in London during first peak of COVID-19 pandemic.

PURPOSE: Compared to younger patients, coronavirus disease 2019 (COVID-19) clinical presentation in older people can be more heterogeneous and fatal. We aim to describe a cohort of older adults admitted in an inner-city London hospital during the first peak of the pandemic. METHODS: A retrospective observational study that enrolled older adults consecutively admitted into two geriatric wards with suspected or confirmed severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. We collected socio-demographic data, comorbidities, symptoms at presentation and/or during admission, biochemical and radiological data and outcomes at 28 days. RESULTS: One hundred twenty-four patients were included, and 75% were > 80 years old. 19.5% of COVID-19 cases were judged to be hospital-acquired. More than half presented or developed typical symptoms, respiratory failure or fatigue. 46.8% were diagnosed with delirium, 24.2% with falls and dysphagia was present in 13.7%. The mortality rate was 29.8% and was higher among males, those > 80 years, patients with a higher grade of frailty, a history of dementia or chronic kidney disease, as well as those diagnosed with respiratory failure, acute kidney injury or hypernatremia. Independent predictors of mortality were male sex, age > 80 years, respiratory failure and hypernatremia. CONCLUSION: We have described a cohort of patients with SARS-CoV-2 infection in the first UK peak of the global pandemic. We found that these patients had significant frailty with multiple comorbidities. There was a high mortality and increased dependency and greater social care need in survivors.

Cost Drivers in Carpal Tunnel Release Surgery: An Analysis of 8,717 Patients in New York State.

PURPOSE: The annual high volume of carpal tunnel releases (CTRs) has a large financial impact on the health care system. Validating the cost drivers related to CTR in a large, diverse patient population may aid in developing cost reduction strategies to benefit health care systems. METHODS: Adult patients with carpal tunnel syndrome who underwent CTR were identified in the New York Statewide Planning and Research Cooperative System database from 2016 to 2017. The Statewide Planning and Research Cooperative System is a comprehensive all-payer database that collects all inpatient and outpatient preadjudicated claims in New York. A multivariable mixed model regression with random effects was performed for the facility to assess the variables that contributed significantly to the total charge. The variables included were patient age, sex, anesthesia method, whether the surgery took place in an ambulatory surgery center or a hospital outpatient department, operation time in minutes, primary insurance type, race, ethnicity, Charlson Comorbidity Index, and categories for billed procedure codes. RESULTS: During the period of 2016 to 2017, 8,717 claims were included, with a mean charge per claim of $4,865. General anesthesia was associated with higher charges than local anesthesia. A procedure at a hospital outpatient department was associated with an approximately 48.2% increase in the total charge compared with that at an ambulatory surgery center. A 1-minute increase in the operation time was associated with a 0.3% increase in the total charge. Claims with antiemetics, antihistamines, benzodiazepines, intravenous fluids, narcotic agents, or preoperative antibiotics were associated with higher total charges than claims that did not bill for these. Compared with endoscopic procedures, open procedures had a 44.3% decrease in the total charges. CONCLUSIONS: This comprehensive multivariable model has validated that general anesthesia, hospital-based surgery, the use of antibiotics and opioids, longer operative times, and endoscopic CTR significantly increased the cost of surgery. TYPE OF STUDY/LEVEL OF EVIDENCE: Economic and decision analyses II.

Demographic Disparities amongst Patients Receiving Carpal Tunnel Release: A Retrospective Review of 92,921 Patients.

Despite strong evidence supporting the efficacy of surgical release for carpal tunnel syndrome (CTS), previous studies have suggested that surgery is not performed equally amongst races and sex. The purpose of this study was to investigate potential socioeconomic disparities in the surgical treatment for CTS. METHODS: Adult patients (≥18) were identified in the New York Statewide Planning and Research Cooperative System database from 2011 to 2018 by diagnosis code for CTS. All carpal tunnel surgery procedures in the outpatient setting were identified using Current Procedural Terminology codes. Using a unique identifier for each patient, the diagnosis data were linked to procedure data. A multivariable logistic regression was performed to assess the impact of patient factors on the likelihood of receiving surgery. RESULTS: In total, 92,921 patients with CTS were included in the analysis and 30,043 (32.3%) went on to have surgery. Older age and workers compensation insurance had increased the odds of surgery. Feminine gender had lower odds of surgery. Asian, African American, and other races had decreased odds of surgery relative to the White race. Patients of Hispanic ethnicity had decreased odds of surgery compared with non-Hispanic ethnicity. Patients with Medicare, Medicaid, or self-pay insurance were all less likely to undergo surgery relative to private insurance. Higher social deprivation was also associated with decreased odds of surgery. CONCLUSIONS: Surgical treatment of CTS is unequally distributed amongst gender, race, and socioeconomic status. Additional research is necessary to identify the cause of these disparities to improve equity in patient care.

Adropin decreases endothelial monolayer permeability after cell-free hemoglobin exposure and reduces MCP-1-induced macrophage transmigration.

BACKGROUND: Cell-free heme-containing proteins mediate endothelial injury in a variety of disease states including subarachnoid hemorrhage and sepsis by increasing endothelial permeability. Inflammatory cells are also attracted to sites of vascular injury by monocyte chemotactic protein 1 (MCP-1) and other chemokines. We have identified a novel peptide hormone, adropin, that protects against hemoglobin-induced endothelial permeability and MCP-1-induced macrophage migration. METHODS: Human microvascular endothelial cells were exposed to cell-free hemoglobin (CFH) with and without adropin treatment before measuring monolayer permeability using a FITC-dextran tracer assay. mRNA and culture media were collected for molecular studies. We also assessed the effect of adropin on macrophage movement across the endothelial monolayer using an MCP-1-induced migration assay. RESULTS: CFH exposure decreases adropin expression and increases paracellular permeability of human endothelial cells. Treating cells with synthetic adropin protects against the increased permeability observed during the natural injury progression. Cell viability was similar in all groups and Hmox1 expression was not affected by adropin treatment. MCP-1 potently induced macrophage migration across the endothelial monolayer and adropin treatment effectively reduced this phenomenon. CONCLUSIONS: Endothelial injury is a hallmark of many disease states. Our results suggest that adropin treatment could be a valuable strategy in preventing heme-mediated endothelial injury and macrophage infiltration. Further investigation of adropin therapy in animal models and human tissue specimens is needed.

A Modification to a Murine Model for Intracranial Aneurysm Formation and Rupture.

Between 3.6% and 6.0% of the population has an intracranial aneurysm. The mechanisms underlying intracranial aneurysm formation and rupture are not fully known. Several rodent models have been developed to better understand intracranial aneurysm pathophysiology. Hypertension, hemodynamic changes, and vessel injury are all necessary for aneurysm induction; however, multiple invasive procedures may disrupt an animal's physiology. Therefore, we hypothesized that our method for inducing hypertension could be modified to create a simpler model. We previously developed a highly reproducible murine model of intracranial aneurysm formation and rupture that involves hemodynamic changes through ligation of the left common carotid artery, vessel wall degradation using elastase and a lysyl oxidase inhibitor, and hypertension through a high-salt diet, continuous angiotensin II infusion, and right renal artery ligation. In order to create a simpler model, we sought to eliminate renal artery ligation. We assessed aneurysm formation, aneurysm rupture, and blood pressure in two separate cohorts of C57BL/6 mice: one cohort underwent our model as above, while another cohort did not receive right renal artery ligation. Our results demonstrate that intracranial aneurysm formation and rupture rates did not differ between each group. Further, the blood pressures between cohorts did not differ at various timepoints in the model. Both cohorts, however, did have a significant increase in blood pressure from baseline, suggesting that renal artery ligation is not needed for inducing hypertension. These findings demonstrate that our murine model can be modified to eliminate right renal artery ligation. Thus, we propose this modification to our murine model for studying intracranial aneurysm pathophysiology.

Crisis Management Simulation: The Value of Interdisciplinary Debriefing.

OBJECTIVE: Simulation offers an important avenue for surgical and anesthesia training. This is especially important for crisis management scenarios where individuals need to act quickly and efficiently for optimal patient care. Practice based performance can be measured and real time feedback provided during debriefing scenarios. METHODS: In this paper, we highlight a dual anesthesia and otolaryngology cavernous carotid injury scenario. The trials were run three different times with inter-trial debriefing. RESULTS: The focused debriefing improved resident performance in terms of blood loss on subsequent trials. Furthermore, the learners provided important feedback regarding the utility of training and how it improved their ability to handle crisis management scenarios in the future. CONCLUSION: Debriefing for crisis management in a simulation trial improves performance and trainee confidence. Follow up studies will evaluate real world effectiveness over a longer follow up period.

Crisis Management Simulation: Review of Current Experience.

Crisis management simulation is important in training the next generation of surgeons. In this review, we highlight our experiences with the cavernous carotid injury model. We then delve into other crisis simulation models available for the neurosurgical specialty. The discussion focuses upon how these trainings can continue to evolve. Much work is yet to be done in this exciting arena and we present several avenues for future discovery. Simulation continues to be an important training tool for the surgical learner.