Remote RF excitation for small-bore MR imager at 15.2 T

We report a method for remote excitation of the RF signal for preclinical-equivalent ultra high field Magnetic Resonance Imaging (MRI). A parallel-plate waveguide together with a bio-inspired surface coil were used to perform remote excitation experiments to acquire images with a small-bore MR imager at 15.2 T. The imager bore size limits the RF coil transmitter dimensions, so the Gielis super-formula was used to design an RF coil with small dimensions. Electromagnetic simulations of the principal mode were run to study the waveguide filled with air and loaded with a saline solution-filled tube. Radiation patterns were also computed in a semi-anechoic chamber for the same scenarios as above. A saline solution-filled spherical phantom and a formaldehyde-fixed mouse phantom were used to acquire images. Radiation patterns showed an omnidirectional distribution with no side lobes, and a very smooth behaviour with almost no loss of information in the saline solution-filled tube and without. The theoretical wave impedance was calculated and compared with simulated results showing an excellent correspondence. Spherical phantom image data and simulation results of B₁ were contrasted and showed an important correlation. Ex vivo mouse images were of high quality and exhibited clear delineation of anatomical structures. These imaging results are in very good agreement with the simulations. Numerical, theoretical and experimental results validate this approach, using a bio-inspired surface coil with a simple waveguide for preclinical small-bore MRI at ultra high field.

The Zebrafish Information Network: major gene page and home page updates

The Zebrafish Information Network (ZFIN) (https://zfin.org/) is the database for the model organism, zebrafish (Danio rerio). ZFIN expertly curates, organizes, and provides a wide array of zebrafish genetic and genomic data, including genes, alleles, transgenic lines, gene expression, gene function, mutant phenotypes, orthology, human disease models, gene and mutant nomenclature, and reagents. New features at ZFIN include major updates to the home page and the gene page, the two most used pages at ZFIN. Data including disease models, phenotypes, expression, mutants and gene function continue to be contributed to The Alliance of Genome Resources for integration with similar data from other model organisms.

Actin-binding protein profilin1 promotes aggressiveness of clear-cell renal cell carcinoma cells

Clear-cell renal cell carcinoma (ccRCC), the most common subtype of renal cancer, has a poor clinical outcome. A hallmark of ccRCC is genetic loss-of-function of VHL (von Hippel-Lindau) that leads to a highly vascularized tumor microenvironment. Although many ccRCC patients initially respond to antiangiogenic therapies, virtually all develop progressive, drug-refractory disease. Given the role of dysregulated expressions of cytoskeletal and cytoskeleton-regulatory proteins in tumor progression, we performed analyses of The Cancer Genome Atlas (TCGA) transcriptome data for different classes of actin-binding proteins to demonstrate that increased mRNA expression of profilin1 (Pfn1), Arp3, cofilin1, Ena/VASP, and CapZ, is an indicator of poor prognosis in ccRCC. Focusing further on Pfn1, we performed immunohistochemistry-based classification of Pfn1 staining in tissue microarrays, which indicated Pfn1 positivity in both tumor and stromal cells; however, the vast majority of ccRCC tumors tend to be Pfn1-positive selectively in stromal cells only. This finding is further supported by evidence for dramatic transcriptional up-regulation of Pfn1 in tumor-associated vascular endothelial cells in the clinical specimens of ccRCC. In vitro studies support the importance of Pfn1 in proliferation and migration of RCC cells and in soluble Pfn1's involvement in vascular endothelial cell tumor cell cross-talk. Furthermore, proof-of-concept studies demonstrate that treatment with a novel computationally designed Pfn1-actin interaction inhibitor identified herein reduces proliferation and migration of RCC cells in vitro and RCC tumor growth in vivo Based on these findings, we propose a potentiating role for Pfn1 in promoting tumor cell aggressiveness in the setting of ccRCC.

Artificial intelligence-guided image acquisition on patients with implanted electrophysiological devices: results from a pivotal prospective multi-center clinical trial

Background

A novel, recently FDA-authorized software uses deep learning (DL) to provide prescriptive transthoracic echocardiography (TTE) guidance, allowing novices to acquire standard TTE views. The DL model was trained by >5,000,000 observations of the impact of probe motion on image orientation/quality. This study evaluated whether novice-acquired TTE images guided by this software were of diagnostic quality in patients with and without implanted electrophysiological (EP) devices, focusing on RV size and function, which were thought to be sensitive to EP devices. Some aspects of the study have previously been presented.

Methods

240 patients (61±16 years old, 58% male, 33% BMI >30 kg/m2, 91% with cardiac pathology) were recruited. 8 nurses without echo experience each acquired 10 view TTEs in 30 patients guided by the software. 235 of the patients were also scanned by a trained sonographer without assistance from the software. 5 Level 3 echocardiographers independently assessed the diagnostic quality of the TTEs acquired by the nurses and sonographers to evaluate the effect of EP devices on DL software performance.

Results

Nurses using the AI-guided acquisition software acquired TTEs of sufficient quality to make qualitative assessments of right ventricular (RV) size and function in greater than 80% of cases for patients with and without implanted EP devices (Table). There was no significant difference between nurse- and sonographer-acquired scans.

Conclusion

These results indicate that new DL software can guide novices to obtain TTEs that enable qualitative assessment of RV size even in the presence of implanted EP devices. The results of the comparison to sonographer-acquired exams indicate the software performance is robust to presence of pacemaker/ICD leads visible in the images (Figure).

Nurse-acquired TTE with visible ICD lead

Funding Acknowledgement

Type of funding source: Private company. Main funding source(s): Caption Health, Inc.

High-Resolution X-ray Photoelectron Spectroscopy of an IrO2(110) Film on Ir(100)

High-resolution X-ray photoelectron spectroscopy (XPS) and density functional theory (DFT) were used to characterize IrO₂(110) films on Ir(100) with stoichiometric as well as OH-rich terminations. Core-level Ir 4f and O 1s peaks were identified for the undercoordinated Ir and O atoms and bridging and on-top OH groups at the IrO₂(110) surfaces. Peak assignments were validated by comparison of the core-level shifts determined experimentally with those computed using DFT, quantitative analysis of the concentrations of surface species, and the measured variation of the Ir 4f peak intensities with photoelectron kinetic energy. We show that exposure of the IrO₂(110) surface to O₂ near room temperature produces a large quantity of on-top OH groups because of reaction of background H₂ with the surface. The peak assignments made in this study can serve as a foundation for future experiments designed to utilize XPS to uncover atomic-level details of the surface chemistry of IrO₂(110).

Mortality following combined burn and traumatic brain injuries: An analysis of the national trauma data bank of the American College of Surgeons

BACKGROUND

Severe burn and traumatic brain injuries (TBI) lead to significant mortality, and combined burn-TBI injuries may predispose towards even worse outcomes. The purpose of this study was to investigate the mortality of patients with burn, burn with non-TBI trauma, and combined burn/TBI to determine if combined injury portends a worse outcome.

METHODS

We obtained the National Trauma Data Bank from 2007 to 2012, identifying 32,334 patients with burn related injuries, dividing this cohort into three injury types: BURN ONLY, BURN with TRAUMA/NO TBI, and BURN with TBI. For each patient, demographic data was obtained, including age, gender, presence of trauma, TBI, or inhalation injury, burn total body surface area (TBSA), Glasgow Coma Scale, Injury Severity Score, and mortality. Multivariable logistic regression was performed.

RESULTS

Age, gender, and TBSA were similar across the three injury groups, but the incidence of inhalation injury was doubled in the BURN with TRAUMA/NO TBI (15.4 %) and BURN with TBI (15.3 %) groups when compared to the BURN ONLY (7.2 %) group. Mortality differed across injury categories after adjusting for age, TBSA, and inhalation injury. Increased mortality was seen in BURN with TRAUMA/NO TBI versus BURN ONLY (OR = 1.27 [1.06, 1.53]) and was higher when comparing BURN with TBI versus BURN ONLY (OR = 4.22 [2.85, 6.18]). BURN with TBI also had higher mortality when compared to BURN with TRAUMA/NO TBI (OR = 3.33 [2.30, 4.82]). The logs odds of mortality also increased with increasing age, TBSA and presence of inhalation injury.

DISCUSSION

This analysis of the NTDB suggests that mortality following burn-related injuries may be higher when burn injury is combined with TBI when compared to burns with other trauma, even after correcting for age, TBSA, and inhalation injury. Further clinical and laboratory research is needed to validate these findings and better understand how to optimize combined TBI and burn injury treatment.

Treatment of adults with intracranial hemorrhage on apixaban or rivaroxaban with prothrombin complex concentrate products

To analyze the efficacy and safety of activated prothrombin complex concentrates (aPCC) and four-factor prothrombin complex concentrates (4F-PCC) to prevent hematoma expansion in patients taking apixaban or rivaroxaban with intracranial hemorrhage (ICH). In this multicenter, retrospective study, sixty-seven ICH patients who received aPCC or 4F-PCC for known use of apixaban or rivaroxaban between February 2014 and September 2018 were included. The primary outcome was the percentage of patients who achieved excellent/good or poor hemostasis after administration of aPCC or 4F-PCC. Secondary outcomes included hospital mortality, thromboembolic events during admission, and transfusion requirements. Excellent/good hemostasis was achieved in 87% of aPCC patients, 89% of low-dose 4F-PCC [< 30 units per kilogram (kg)], and 89% of high-dose 4F-PCC (≥ 30 units per kg). There were no significant differences in excellent/good or poor hemostatic efficacy (p = 0.362). No differences were identified in transfusions 6 h prior (p = 0.087) or 12 h after (p = 0.178) the reversal agent. Mortality occurred in five patients, with no differences among the groups (p = 0.838). There were no inpatient thromboembolic events. Both aPCC and 4F-PCC appear safe and equally associated with hematoma stability in patients taking apixaban or rivaroxaban who present with ICH. Prospective studies are needed to identify a superior reversal agent when comparing andexanet alfa to hospital standard of care (4F-PCC or aPCC) and to further explore the optimal dosing strategy for patients with ICH associated with apixaban or rivaroxaban use.

OP0227 SECUKINUMAB VERSUS ADALIMUMAB HEAD-TO-HEAD COMPARISON IN BIOLOGIC-NAÏVE PATIENTS WITH ACTIVE PSORIATIC ARTHRITIS THROUGH 52-WEEKS (EXCEED): A RANDOMISED, DOUBLE-BLIND, PHASE-3B STUDY

Background:

Secukinumab (SEC), an interleukin-17A inhibitor, has demonstrated improvements on multiple domains of psoriatic arthritis (PsA).1Adalimumab (ADA), a TNF inhibitor, is widely used as a first–line biologic in PsA.

Objectives:

To report efficacy and safety outcomes from the head-to-head EXCEED trial (NCT02745080) that compares SECvs.ADA as first–line biologic monotherapy through 52-weeks (wks), with a musculoskeletal primary endpoint in pts with active PsA.

Methods:

Head-to-head, phase-3b, randomised, double-blind trial: biologic naïve active PsA pts were randomised to receive SEC 300mg subcutaneous at baseline, Wk1-4, and then every 4wks (q4w) until Wk48 or ADA 40mg subcutaneous at baseline and then q2w until Wk50. The primary endpoint was superiority of SECvs.ADA on ACR20 response at Wk52. Binary and continuous variables were analysed using logistic-regression model and MMRM, respectively. Safety analysis included patients who received ≥1 dose of study-drug.

Results:

853 pts were randomised to receive SEC (n=426) or ADA (n=427). Baseline demographics and disease characteristics were comparable between treatment-groups except higher proportion of female pts and pts without enthesitis in the SEC group. ACR20 response at Wk52 for SECvs.ADA were 67·4%vs.61·5%, respectively (p=0·0719) (Figure). Higher clinical responses were observed with SECvs.ADA for a range of musculoskeletal, skin, and higher-hurdle outcomes (Table). A higher retention rate was observed for SEC (85.7%)vs.ADA (76.3%). Safety profiles of SEC and ADA were consistent with previous reports.2,3

Conclusion:

Results suggest that SEC is at least as efficacious as ADA on musculoskeletal endpoints whilst providing higher responses on skin endpoints, and is associated with a higher retention rate. No new safety signals were reported.

References:

[1]van der Heijde, et al. Rheumatol. (Oxford).2019; DOI10.1093/rheumatology/kez420.

[2]Deodhar A, et al. Arthritis Res Ther. 2019;21:111.

[3]Burmester GR, et al. Ann Rheum Dis.2013; 72:517-24.

Figure.

ACR20 Response through Wk 52

Table.

Efficacy Outcomes at Wk 52

Endpoints, % response unless specified otherwiseSEC 300 mg(N=426)ADA 40 mg(N=427)P-value (unadjusted)*ACR2067·461·50·0719aACR2066·959·50·0239Key SecondarybPASI 9065·443·2<0·0001ACR5049·044·80·2251HAQ-DI mean change from baseline ± SE-0·58 ± 0.03-0·56 ± 0.030·5465cResolution of enthesitis (based on LEI)60·554·20·1498ExploratoryMDA43·037·90·1498VLDA18·116·60·6107DAPSA LDA+Remission61·753·10·0178PASDAS LDA+Remission51·144·10·0557

*Unadjusted P-valuesvsADA

Binary variables were analysed using logistic regression. Pts who discontinued study treatment prematurely or took csDMARDs after week-36 were considered non-responders. Multiple imputation was used for all other missing data. HAQ-DI mean change from baseline was analysed using mixed-effect model repeated measures

aNon-responder imputation was used for pre-specified sensitivity analysis

bN=215 in SEC and N=202 in ADA in psoriasis subset

cN=234 in SEC and N=264 in ADA in enthesitis subset

Disclosure of Interests:

Iain McInnes Grant/research support from: Bristol-Myers Squibb, Celgene, Eli Lilly and Company, Janssen, and UCB, Consultant of: AbbVie, Bristol-Myers Squibb, Celgene, Eli Lilly and Company, Gilead, Janssen, Novartis, Pfizer, and UCB, Frank Behrens Grant/research support from: Pfizer, Janssen, Chugai, Celgene, Lilly and Roche, Consultant of: Pfizer, AbbVie, Sanofi, Lilly, Novartis, Genzyme, Boehringer, Janssen, MSD, Celgene, Roche and Chugai, Philip J Mease Grant/research support from: Abbott, Amgen, Biogen Idec, BMS, Celgene Corporation, Eli Lilly, Novartis, Pfizer, Sun Pharmaceutical, UCB – grant/research support, Consultant of: Abbott, Amgen, Biogen Idec, BMS, Celgene Corporation, Eli Lilly, Novartis, Pfizer, Sun Pharmaceutical, UCB – consultant, Speakers bureau: Abbott, Amgen, Biogen Idec, BMS, Eli Lilly, Genentech, Janssen, Pfizer, UCB – speakers bureau, Arthur Kavanaugh Grant/research support from: Abbott, Amgen, AstraZeneca, BMS, Celgene Corporation, Centocor-Janssen, Pfizer, Roche, UCB – grant/research support, Christopher T. Ritchlin Grant/research support from: UCB Pharma, AbbVie, Amgen, Consultant of: UCB Pharma, Amgen, AbbVie, Lilly, Pfizer, Novartis, Gilead, Janssen, Peter Nash Grant/research support from: AbbVie, Bristol-Myers Squibb, Celgene, Eli Lilly and Company, Gilead, Janssen, MSD, Novartis, Pfizer Inc, Roche, Sanofi, UCB, Consultant of: AbbVie, Bristol-Myers Squibb, Celgene, Eli Lilly, Gilead, Janssen, MSD, Novartis, Pfizer Inc, Roche, Sanofi, UCB, Speakers bureau: AbbVie, Bristol-Myers Squibb, Celgene, Eli Lilly, Gilead, Janssen, MSD, Novartis, Pfizer Inc, Roche, Sanofi, UCB, Jordi Gratacos-Masmitja Grant/research support from: a grant from Pfizzer to study implementation of multidisciplinary units to manage PSA in SPAIN, Consultant of: Pfizzer, MSD, ABBVIE, Janssen, Amgen, BMS, Novartis, Lilly, Speakers bureau: Pfizzer, MSD, ABBVIE, Janssen, Amgen, BMS, Novartis, Lilly, Philippe Goupille Grant/research support from: AbbVie, Amgen, Biogen, BMS, Celgene, Chugai, Lilly, Janssen, Medac, MSD France, Nordic Pharma, Novartis, Pfizer, Sanofi and UCB, Consultant of: AbbVie, Amgen, Biogen, BMS, Celgene, Chugai, Lilly, Janssen, Medac, MSD France, Nordic Pharma, Novartis, Pfizer, Sanofi and UCB, Speakers bureau: AbbVie, Amgen, Biogen, BMS, Celgene, Chugai, Lilly, Janssen, Medac, MSD France, Nordic Pharma, Novartis, Pfizer, Sanofi and UCB, Tatiana Korotaeva Grant/research support from: Pfizer, Consultant of: Abbvie, BIOCAD, Bristol-Myers Squibb, Celgene, Eli Lilly, Janssen, Merck Sharp & Dohme, Novartis, Novartis-Sandoz, Pfizer, UCB, Speakers bureau: Abbvie, BIOCAD, Bristol-Myers Squibb, Celgene, Eli Lilly, Janssen, Merck Sharp & Dohme, Novartis, Novartis-Sandoz, Pfizer, UCB, Alice B Gottlieb Grant/research support from:: Research grants, consultation fees, or speaker honoraria for lectures from: Pfizer, AbbVie, BMS, Lilly, MSD, Novartis, Roche, Sanofi, Sandoz, Nordic, Celltrion and UCB., Consultant of:: Research grants, consultation fees, or speaker honoraria for lectures from: Pfizer, AbbVie, BMS, Lilly, MSD, Novartis, Roche, Sanofi, Sandoz, Nordic, Celltrion and UCB., Speakers bureau:: Research grants, consultation fees, or speaker honoraria for lectures from: Pfizer, AbbVie, BMS, Lilly, MSD, Novartis, Roche, Sanofi, Sandoz, Nordic, Celltrion and UCB., Ruvie Martin Shareholder of: Novartis, Employee of: Novartis, Kevin Ding Employee of: Novartis, Pascale Pellet Shareholder of: Novartis, Employee of: Novartis, Shephard Mpofu Shareholder of: Novartis, Employee of: Novartis, Luminita Pricop Shareholder of: Novartis, Employee of: Novartis

Factor Xa Inhibitor-Related Intracranial Hemorrhage

Background:

Since the approval of the oral factor Xa inhibitors, there have been concerns regarding the ability to neutralize their anticoagulant effects after intracranial hemorrhage (ICH). Multiple guidelines suggest using prothrombin complex concentrates (PCCs) in these patients on the basis of research that includes a limited number of patients with ICH. Given this, we aimed to evaluate the safety and efficacy of PCCs for factor Xa inhibitor–related ICH in a large, multicenter cohort of patients.

Methods:

This was a multicenter, retrospective, observational cohort study of patients with apixaban- or rivaroxaban-related ICH who received PCCs between January 1, 2015, and March 1, 2019. The study had 2 primary analysis groups: safety and hemostatic efficacy. The safety analysis evaluated all patients meeting inclusion criteria for the occurrence of a thrombotic event, which were censored at hospital discharge or 30 days after PCC administration. Patients with intracerebral, subarachnoid, or subdural hemorrhages who had at least 1 follow-up image within 24 hours of PCC administration were assessed for hemostatic efficacy. The primary efficacy outcome was the percentage of patients with excellent or good hemostasis on the basis of the modified Sarode criteria. Secondary outcomes included an evaluation of in-hospital mortality, length of stay, infusion-related reactions, and thrombotic event occurrence during multiple predefined periods.

Results:

A total of 663 patients were included and assessed for safety outcomes. Of these, 433 patients met criteria for hemostatic efficacy evaluation. We observed excellent or good hemostasis in 354 patients (81.8% [95% CI, 77.9–85.2]). Twenty-five (3.8%) patients had a total of 26 thrombotic events, of which 22 occurred in the first 14 days after PCC administration. One patient had documentation of an infusion-related reaction. For the full cohort of patients, in-hospital mortality was 19.0%, and the median intensive care unit and hospital lengths of stay were 2.0 and 6.0 days, respectively.

Conclusions:

Administration of PCCs after apixaban- and rivaroxaban-related ICH provided a high rate of excellent or good hemostasis (81.8%) coupled with a 3.8% thrombosis rate. Randomized, controlled trials evaluating the clinical efficacy of PCCs in patients with factor Xa inhibitor–related ICH are needed.

Thinking Small to Think Big: Modular Approach for Autism Programming in Schools (MAAPS)

To date there are no evidence-based comprehensive interventions for use in school settings. There are numerous barriers to delivery of high-quality interventions in schools that have limited the transfer of research-based interventions to school settings. Modular Approach to Autism Programing for Schools (MAAPS) is a framework for implementation of evidence-based interventions in school settings that is designed to address these barriers. The development and initial evaluation of MAAPS was conducted using an implementation-science framework and results indicate that MAAPS is aligned with needs and resources available in schools, that it had excellent social validity, and that there is good evidence that MAAPS is effective for addressing core and associated features of autism in educational settings.

The Zebrafish Information Network: new support for non-coding genes, richer Gene Ontology annotations and the Alliance of Genome Resources

The Zebrafish Information Network (ZFIN) (https://zfin.org/) is the database for the model organism, zebrafish (Danio rerio). ZFIN expertly curates, organizes and provides a wide array of zebrafish genetic and genomic data, including genes, alleles, transgenic lines, gene expression, gene function, mutant phenotypes, orthology, human disease models, nomenclature and reagents. New features at ZFIN include increased support for genomic regions and for non-coding genes, and support for more expressive Gene Ontology annotations. ZFIN has recently taken over maintenance of the zebrafish reference genome sequence as part of the Genome Reference Consortium. ZFIN is also a founding member of the Alliance of Genome Resources, a collaboration of six model organism databases (MODs) and the Gene Ontology Consortium (GO). The recently launched Alliance portal (https://alliancegenome.org) provides a unified, comparative view of MOD, GO, and human data, and facilitates foundational and translational biomedical research.

Tracking the dynamic ecological history of a tropical urban estuary as it responds to human pressures

Coastal cities in tropical areas are often low-lying and vulnerable to the effects of flooding and storms. San Juan, Puerto Rico is a good example of this. It is built around a lagoon-channel complex called the San Juan Bay Estuary (SJBE). A critical channel in the estuary, the Caño Martín Peña, has filled in and now frequently floods the surrounding communities with sewage-enriched waters, causing a series of human health and ecological problems. Sediment core analyses indicate that portions of the SJBE now function as settling basins. High urban and sewage runoff to the Caño contributes nitrogen (N), but stable isotope and sediment nutrient analyses indicate that this runoff may also enhance conditions for coupled sulfate reduction-nitrogen fixation. The amount of 'new' bioavailable N created from inert atmospheric N₂ gas may meet or exceed that from the runoff into the Caño Martín Peña. The ecological consequences of this appear to extend beyond the ponded channel, potentially contributing to the poor water quality of the SJBE, greater than contaminated runoff alone.

Molecular chemisorption of N2 on IrO2(110)

We investigated adsorption of N₂ on stoichiometric and O-rich IrO₂(110) surfaces using temperature programmed desorption (TPD) experiments and density functional theory (DFT) calculations. TPD shows that N₂ desorbs predominantly from the stoichiometric-IrO₂(110) surface in a well-defined peak at 270 K for N₂ coverages below about 0.5 ML and that a shoulder centered near 235 K develops in the N₂ TPD traces as the coverage approaches saturation, indicating that adsorbed N₂ molecules destabilize at high N₂ coverages. Experiments of N₂ adsorption onto O-rich IrO₂(110) surfaces provide evidence that N₂ adsorbs exclusively on the coordinatively unsaturated Ir atoms (Ir_cus) of the surface and that pre-adsorbed O-atoms ("on-top" oxygen) stabilize adsorbed N₂ molecules, causing the main N₂ TPD peak to shift toward higher temperature with increasing oxygen coverages. Consistent with prior results, our DFT calculations predict that an N₂ molecule preferentially adsorbs into an upright configuration on an Ir_cus atom of the IrO₂(110) surface and achieves a binding energy of about 100 kJ/mol. The computed binding energy agrees well with our experimental estimate of ∼90 kJ/mol for low N₂ coverages on stoichiometric IrO₂(110). The DFT calculations also quantitatively reproduce the observed stabilization of N₂ by co-adsorption on-top O-atoms and predict the destabilization of N₂ on IrO₂(110) as the N₂ adlayer becomes crowded at high coverages.

The Increasing Age of TBI Patients at a Single Level 1 Trauma Center and the Discordance Between GCS and CT Rotterdam Scores in the Elderly

Introduction: Traumatic brain injury (TBI) is frequently encountered in geriatric patients, but there is a paucity of data describing TBI in the elderly. Here, we show the age of patients with TBI is increasing at our medical center and discuss the relationship between age and injury severity with patient outcomes. Methods: This is a retrospective analysis of 3,179 adult patients with TBI treated at the University of California, Davis Level 1 Trauma Center between 2009 and 2016. Age, Glasgow Coma Scale (GCS), and CT Rotterdam Scores were recorded. Age was analyzed as both a continuous and categorical variable (18-34, 35-50, 51-65, >65 years-old). Extended Glasgow Outcome Scale was obtained at 3 and 6 months and dichotomized into favorable and unfavorable outcomes. Multivariable general linear regression models, chi-square, logistic regression analyses and ANOVA were used for statistical analyses; a p < 0.05 was considered significant. Results: The mean age of patients was 52.2 ± 21.9 years with a male predominance (69%). There was a significant trend (p = 0.002) toward an increase in mean age each year, increasing by 4.4 years (p = 0.008) over the course of the analysis. Older patients had a higher mean GCS compared to younger patients with the same CT Rotterdam Score (p = 0.027), this becoming more pronounced with worse CT Rotterdam Scores. The >65 group had a 4-fold increased risk for unfavorable outcome when compared to the 18-34 group, this effect being most pronounced after mild TBI. Conclusions: The mean age of TBI patients is increasing at our trauma center. The largest disparity in outcomes across age was seen in patients with a mild GCS and low CT Rotterdam Scores, suggesting that these markers of injury severity may underestimate the severity of injury in the elderly population. This information highlights the need for clinical trials and validation of outcome markers in geriatric TBI.

VIS-IT: Visualizing the Injured Tibia-A Cadaveric Study of Limb Positioning for Posterolateral Tibial Plateau Fracture Visualization

Posterolateral tibial plateau (PLTP) fractures are often associated with anterior cruciate ligament (ACL) incompetence, such as tibial eminence fractures. Both occur from a pivot shift like mechanism. Malreductions of the tibial plateau most frequently occur in the posterolateral quadrant. Acquiring adequate intraoperative visualization of the PLTP poses a challenge. We hypothesized that visualization of PLTP could be improved by positioning the knee at 110 degrees of flexion with the addition of a varus anterolateral rotatory vector. This position and maneuver take advantage of both the nonisometric nature of the lateral soft tissues and, when present, ACL incompetence. In this cadaveric study, we digitally quantified the percentage of the lateral tibial plateau visualized under different conditions after performing an anterolateral surgical approach with submeniscal arthrotomy. Four conditions were assessed for articular visualization: (1) 30 degrees of knee flexion, (2) 110 degrees of knee flexion, (3) 110-degrees of knee flexion plus varus anterolateral rotatory vector, (4) 110-degrees of knee flexion plus varus anterolateral rotatory vector with ACL sacrifice (ACL incompetence model). In the ACL competent models, maximal lateral tibial plateau exposure was obtained with the knee positioned at 110 degrees of flexion with a varus anterolateral rotatory vector (58.2%, range: 52.9-63.4%). Articular visualization was further improved with the ACL incompetent model (82.4%, range: 77.1-87.7%), modeling a tibial eminence fracture.