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X-ray tomography is a non-destructive imaging technique that reveals the interior of an object from its projections at different angles. Under sparse-view and low-photon sampling, regularization priors are required to retrieve a high-fidelity reconstruction. Recently, deep learning has been used in X-ray tomography. The prior learned from training data replaces the general-purpose priors in iterative algorithms, achieving high-quality reconstructions with a neural network. Previous studies typically assume the noise statistics of testing data is acquired a priori from training data, leaving the network susceptible to a change in the noise characteristics under practical imaging conditions. In this work, we propose a noise-resilient deep-reconstruction algorithm for X-ray tomography. By training the network with regularized reconstructions from a conventional algorithm, the learned prior shows strong noise resilience without the need for additional training with noisy examples, and allows us to obtain acceptable reconstructions with fewer photons in testing data. The advantages of our framework may further enable low-photon tomographic imaging where long acquisition times limit the ability to acquire a large training set.

The extent to which music research has penetrated the medical science literature relative to other forms of research remains unclear. We sought to explore temporal changes in the number of music related publications relative to all medical literature as well as prespecified research subdomains of drug therapy, alternative therapy, and neuroscience between 1970 and 2019. We conducted a bibliometric review in which we quantified the number of annual publications between 1970 and 2019 using MEDLINE (PUBMED) search engine and mesh terms of “Music”; “Drug therapy”; “Alternative Medicine”; “Neuroscience”. The number of publications were quantified relative to all publications within their corresponding years. We also examined the types of journals, geographical location of publication (Based on corresponding author), and journal impact factors. To ensure appropriate content, we conducted a hand review of a random 400 abstracts to ensure they met appropriate criteria for music-medical research. We used log-linear regression, to test differences in growth rates. We determined that the relative growth in the number of music publications accelerated at a rate higher than all medical related publications or those confined to drug therapy. The proliferation of music research was attributable to higher rates of neuroscience, alternative therapy, and music therapy research. In conclusion, the temporal growth in number of music research publications relative to other comparators over the past 50 years underscores the importance, relevance, and maturation of music as an evolving discipline of contemporary medical science.

We show three-dimensional reconstructions of a region of an integrated circuit from a 130 nm copper process. The reconstructions employ x-ray computed tomography, measured with a new and innovative high-magnification x-ray microscope. The instrument uses a focused electron beam to generate x rays in a 100 nm spot and energy-resolving x-ray detectors that minimize backgrounds and hold promise for identification of materials within the sample. The x-ray generation target, a layer of platinum, is fabricated on the circuit wafer itself. A region of interest is imaged from a limited range of angles and without physically removing the region from the larger circuit. The reconstruction is consistent with the circuit’s design file.

Face masks do not completely prevent transmission of respiratory infections, but masked individuals are likely to inhale fewer infectious particles. If smaller infectious doses tend to yield milder infections, yet ultimately induce similar levels of immunity, then masking could reduce the prevalence of severe disease even if the total number of infections is unaffected. It has been suggested that this effect of masking is analogous to the pre-vaccination practice of variolation for smallpox, whereby susceptible individuals were intentionally infected with small doses of live virus (and often acquired immunity without severe disease). We present a simple epidemiological model in which mask-induced variolation causes milder infections, potentially with lower transmission rate and/or different duration. We derive relationships between the effectiveness of mask-induced variolation and important epidemiological metrics (the basic reproduction number and initial epidemic growth rate, and the peak prevalence, attack rate and equilibrium prevalence of severe infections). We illustrate our results using parameter estimates for the original SARS-CoV-2 wild-type virus, as well as the Alpha, Delta and Omicron variants. Our results suggest that if variolation is a genuine side-effect of masking, then the importance of face masks as a tool for reducing healthcare burdens from COVID-19 may be under-appreciated.

BACKGROUND: Patients who are dialysis dependent and have secondary hyperparathyroidism (SHPT) may require calcimimetics to reduce parathyroid hormone levels to treatment goals. Medicare currently uses the Transitional Drug Add-on Payment Adjustment (TDAPA) designation under the ESKD Prospective Payment System (“bundled payment”) to pay for calcimimetics (the first products eligible for the adjustment); this payment designation for calcimimetics is expected to conclude after 2020. This study explores variability in calcimimetic use across key patient characteristics and its potential effect on policy options for incorporating calcimimetics permanently into the bundle. METHODS: This descriptive analysis used the 100% sample of Medicare FFS Part B (outpatient) 2018 claims to describe national-, regional-, and patient-level variation (including race, dual eligibility, and dialysis vintage) in calcimimetic use among beneficiaries who are dialysis dependent. RESULTS: A total of 373,874 beneficiaries were analyzed, 28% had ≥90 days of calcimimetic use during 2018. At the national level, the proportion of patients on dialysis using calcimimetics was roughly 80% higher in Black versus non-Black patients on dialysis, 30% higher in patients on dialysis who were dual eligible versus non–dual eligible, and three times higher in patients with a dialysis vintage ≥3 years versus 10% in approximately 20% of dialysis facilities. CONCLUSIONS: Although less than a third of beneficiaries use calcimimetics, certain patient-level characteristics are associated with higher rates of maintenance calcimimetic use. Due to the financial pressure many dialysis facilities face, how calcimimetics are incorporated into the bundle may have a direct effect on facility reimbursement for, and patient access to, therapy. Careful consideration will be required to ensure patients who are vulnerable and require treatment for SHPT do not face barriers to appropriate care.

Purpose: The immediate purpose is to determine the maximum number of tube voltages which are useful for acquiring information in medical computed tomography (CT) along with specific linear combinations of quantities of chemical elements which are observable with the current generation of medical CT machines. The larger purpose is to encourage the development of CT reconstruction algorithms based on the material basis described herein and, ultimately, to tie the measurand of CT to the International System of Units (SI).Methods and Materials: Experimentally, we scanned samples at four tube voltages, namely 80 kV, 100 kV, 120 kV, and 140 kV on a medical CT. The samples included 30 small plastic bottles of powders containing various compounds spanning the atomic numbers from 1 to 20, along with a similar bottle of water and one of air. Using the known chemical formulas and measured masses, we formed a matrix giving the number of Hounsfield units per (mole per cubic meter) at each tube voltage for each of 13 chemical elements. Theoretically, we took the XCOM cross sections, combined them with the tungsten anode spectral model using interpolating cubic splines (TASMICS), with a one-parameter filter, and a simple detector model, and created a similar matrix for the first 20 chemical elements. In the training phase, we found a best-fit parameter. We define the molar Hounsfield unit (HU) potency as the difference in HU values that anadded mole per cubic meter in a given voxel would add to the measured HU value. We built a matrix of molar potencies for each chemical element and tube voltage and performed a singular value decomposition (SVD) on these. In a validation phase, we compared the model predictions to Hounsfield unit measurements on three CT calibration phantoms taken from the literature.Results: We found that we could predict the measured HU potency for the chemical elements within our model. The singular values and singular vectors of the model and powder measurements are in substantial agreement. Application of the Bayesian Information Criterion (BIC) shows that exactly two singular values and singular vectors describes the results over four tube voltages. We were able to give a good account of the HU values measured for the calibration phantoms at several tube voltages for several vendors within our model withoutintroducing additional parameters.Conclusions: Measurements at two tube voltages are necessary and sufficient to extract the available material dependent information in medical CT. The linear combination of elements that can be observed using a medical CT have been characterized, providing a material basis for use in dual-energy reconstruction. This approach provides groundwork for improved reconstruction and for the link of Hounsfield units to the SI.

Vaccine acceptance depends on public trust and confidence in the safety and efficacy of vaccines and\ud immunization, the health system, healthcare professionals and the wider vaccine research community.\ud This systematic review analyses the current breadth and depth of vaccine research literature that explicitly\ud refers to the concept of trust within their stated aims or research questions. After duplicates were\ud removed, 19,643 articles were screened by title and abstract. Of these 2,779 were screened by full text, 35\ud of which were included in the final analysis. These studies examined a range of trust relationships as they\ud pertain to vaccination, including trust in healthcare professionals, the health system, the government, and\ud friends and family members. Three studies examined generalized trust. Findings indicated that trust is\ud often referred to implicitly (19/35), rather than explicitly examined in the context of a formal definition or\ud discussion of the existing literature on trust in a health context. Within the quantitative research analysed,\ud trust was commonly measured with a single-item measure (9/25). Only two studies used validated multiitem\ud measures of trust. Three studies examined changes in trust, either following an intervention or over\ud the course of a pandemic. The findings of this review indicate a disconnect between the current vaccine\ud hesitancy research and the wider health-related trust literature, a dearth in research on trust in low and\ud middle-income settings, a need for studies on how trust levels change over time and investigations on\ud how resilience to trust-eroding information can be built into a trustworthy health system.

Background Procalcitonin (PCT) is a biomarker that rises in bacterial infections and is being increasingly used to support a diagnosis of bacterial pneumonia. In addition, it may be used in cases in which the diagnosis is not clear such as in patients with congestive heart failure (CHF), which may mimic the signs and symptoms of bacterial pneumonia. The PCT assay was implemented at our institution to reduce unnecessary antimicrobial use when evaluating patients for suspected pneumonia. Methods We performed a retrospective analysis of all patients with a discharge diagnosis of CHF, admitted in a 6-month period, to a large community teaching hospital. Patients with documented pneumonia were excluded. Data were collected on demographics, comorbidities to calculate the Charlson Weighted Index of Comorbidity (CWIC) score, clinical and laboratory information, PCT results (if collected), whether antimicrobials were used, and if so, duration of therapy. Data were analyzed using the Mann–Whitney U test. Results We reviewed 299 charts, with 198 (66.2%) included for analysis. The mean age was 70.4 ± 15.0 years, 53% female and 49.5% black. PCT testing was done in 72 (36%) patients; 117 (59%) had antimicrobials given in the emergency department (ED). If the PCT was performed, patients were more likely to receive antibiotics in the ED (79.2% vs. 47.6%, P < 0.0001). Patients who had a PCT drawn were less likely to have antibiotics continued after discharge from the ED (27.6% vs. 73.3%, P < 0.0001). The median duration of antimicrobials was shorter in patients who had a PCT level drawn than those who did not, 1 day (range 0.5–14) vs. 3 days (0.5–61), P < 0.0001. The duration of antimicrobials also tended to be shorter in patients with PCT levels ≤ 0.25 compared with those with levels >0.25, 0.5 days (0.5–12) vs. 1.0 day (0.5–14), p = 0.06. Conclusion Among patients with a discharge diagnosis of CHF, there was an association between the use of the PCT assay and both discontinuation of antibiotics given in the ED as well as decreased duration of antimicrobials in patients. These results support the ongoing use of this test to promote antimicrobial stewardship. Disclosures All authors: No reported disclosures.

Background There are limited data on whether external cooling blankets (ECBs) are beneficial in the treatment of fever that is not related to malignant hyperthermia (MH). There are no established national guidelines for the use of ECBs for fevers other than for MH. Thus, there may be a wide variation in nursing practice related to their use. Methods We performed a cross-sectional survey of adult intensive care unit (ICU) nurses at our hospital, using SurveyMonkeyTM, to evaluate nursing practices related to the use of ECBs in febrile patients other than MH. Data collected from the survey included years of experience as an ICU nurse, type of ICU, when ECBs are used and temperature of initiation and discontinuation. Continuous variables were compared using Student’s t-test and categorical variables were described as frequency distributions. Data were analyzed using SPSS v. 25.0 and a P-value of 0.05 or less was considered to indicate statistical significance. Results We invited 150 nurses to participate in the survey, 61 responded (40.7%). The mean number of years worked in an ICU was 8.6 ± 9.4 years (range: 1–34), 14 (23%) worked in a cardiovascular ICU (CVICU), 22 (36%) worked in a medical ICU (MICU), and 25 (41%) in a surgical ICU (SICU). A total of 58 (95.1%) of nurses reported using ECBs for fever, with 50 (82%) of nurses using ECBs only when other methods failed. MICU nurses (31.8%) were more likely to report using ECBs prior to failed attempt of other anti-pyrexia methods than SICU (16%) and CVICU (0.0%) nurses. There was no association between initiation and termination of ECB use by ICU type, years of nursing experience or a given range of temperature values. Conclusion There was a wide variation of practice among ICU nurses as it relates to the use of ECBs in patients with fevers. Medical ICU nurses tended to use ECBs before failure of other methods compared with other ICU nurses. Standardized protocols should be developed for their use based on existing medical literature. Further studies should be performed to confirm our findings. Disclosures All authors: No reported disclosures.

Author(s): Fechner, Uli; de Graaf, Chris; Torda, Andrew E; Gussregen, Stefan; Evers, Andreas; Matter, Hans; Hessler, Gerhard; Richmond, Nicola J; Schmidtke, Peter; Segler, Marwin HS; Waller, Mark P; Pleik, Stefanie; Shea, Joan-Emma; Levine, Zachary; Mullen, Ryan; van den Broek, Karina; Epple, Matthias; Kuhn, Hubert; Truszkowski, Andreas; Zielesny, Achim; Fraaije, Johannes Hans; Gracia, Ruben Serral; Kast, Stefan M; Bulusu, Krishna C; Bender, Andreas; Yosipof, Abraham; Nahum, Oren; Senderowitz, Hanoch; Krotzky, Timo; Schulz, Robert; Wolber, Gerhard; Bietz, Stefan; Rarey, Matthias; Zimmermann, Markus O; Lange, Andreas; Ruff, Manuel; Heidrich, Johannes; Onlia, Ionut; Exner, Thomas E; Boeckler, Frank M; Bermudez, Marcel; Firaha, Dzmitry S; Holloczki, Oldamur; Kirchner, Barbara; Tautermann, Christofer S; Volkamer, Andrea; Eid, Sameh; Turk, Samo; Rippmann, Friedrich; Fulle, Simone; Saleh, Noureldin; Saladino, Giorgio; Gervasio, Francesco L; Haensele, Elke; Banting, Lee; Whitley, David C; Oliveira Santos, Jana Sopkova-de; Bureau, Ronan; Clark, Timothy; Sandmann, Achim; Lanig, Harald; Kibies, Patrick; Heil, Jochen; Hoffgaard, Franziska; Frach, Roland; Engel, Julian; Smith, Steven; Basu, Debjit; Rauh, Daniel; Kohlbacher, Oliver; Boeckler, Frank M; Essex, Jonathan W; Bodnarchuk, Michael S; Ross, Gregory A; Finkelmann, Arndt R; Goller, Andreas H; Schneider, Gisbert; Husch, Tamara; Schutter, Christoph; Balducci, Andrea; Korth, Martin; Ntie-Kang, Fidele; Gunther, Stefan; Sippl, Wolfgang; Mbaze, Luc Meva'a

Levetiracetam (LEV) has antiepileptogenic effects in animals and is a candidate for prevention of epilepsy after traumatic brain injury. Pharmacokinetics of LEV in TBI patients was unknown. We report pharmacokinetics of TBI subjects≥6years with high PTE risk treated with LEV 55mg/kg/day orally, nasogastrically or intravenously for 30days starting ≤8h after injury in a phase II safety and pharmacokinetic study. Forty-one subjects (26 adults and 15 children) were randomized to PK studies on treatment days 3 and 30. Thirty-six out of forty-one randomized subjects underwent PK study on treatment day 3, and 24/41 subjects underwent PK study on day 30. On day 3, mean T(max) was 2.2h, C(max) was 60.2μg/ml and AUC was 403.7μg/h/ml. T(max) was longer in the elderly than in children and non-elderly adults (5.96h vs. 1.5h and 1.8h; p=0.0001). AUC was non-significantly lower in children compared with adults and the elderly (317.4μg/h/ml vs. 461.4μg/h/ml and 450.2μg/h/ml; p=0.08). C(max) trended higher in i.v.- versus tablet- or n.g.-treated subjects (78.4μg/ml vs. 59μg/ml and 48.2μg/ml; p=0.07). AUC of n.g. and i.v. administrations was 79% and 88% of AUC of oral administration. There were no significant PK differences between days 3 and 30. Treatment of TBI patients with high PTE risk with 55mg/kg/day LEV, a dose with antiepileptogenic effect in animals, results in plasma LEV levels comparable to those in animal studies.

Background. There is no foolproof strategy to identify a pulmonary embolism (PE) in the emergency department, and atypical presentations are common. Negative test results may mislead physicians away from the diagnosis of PE.Objectives. The current report aims to raise awareness of an unusual presentation of massive PE and its diagnosis and management, in the face of limited evidence in the scientific literature.Case Reports. We report the case of a patient with a negative D-Dimer and a negative Computed Tomography contrast angiography of the chest who was diagnosed twenty-seven hours later with a massive PE, as suggested by a bedside echocardiography. The patient was successfully treated with tenecteplase (TNK).Conclusions/Summary. Pulmonary embolism frequently presents atypically and is often a diagnostic challenge. There is limited literature about the treatment of massive PE. Further research on bedside echocardiography for diagnosing PE in unstable patients is warranted. In addition, further study into new thrombolytic agents like tenecteplase in the context of massive and submassive PE is warranted.

Background In recent years, antimicrobial stewardship has become an important topic, shaping policy throughout healthcare, most notably in inpatient institutions. Various strategies are implemented (often in combination) to achieve the goal of more responsible use of antimicrobials. While many facilities have initiated requirements for antimicrobial indications when ordering antimicrobials, there is little data to support their effect. We evaluated the effect of requiring antimicrobial indications on their overall use. Methods In July 2016 we implemented a requirement that an indication must be included on all antimicrobial orders placed in our electronic medical record among inpatients in a 772-bed urban academic hospital. We performed a pre- and post-intervention retrospective analysis of defined daily dosage (DDD) of antimicrobials per 1000 patient-days. DDD/1000 patient-days were calculated based on purchase data, evaluating total antimicrobial use, as well as breakdowns for specific classes and individual agents. Our pre-intervention period was from 7/1–12/31/15 and post-intervention period was 7/1–12/31/16. This was the only new stewardship intervention employed during the study period. Results There was a 21.7% overall reduction in the DDD/1000 patient-days of systemic antibiotics with net reductions in all major drug classes (Table). The largest reductions occurred in the penicillins and extended-spectrum penicillin drug classes. Drug class 2015 2016 % change Total systemic antibiotics 872.8 683.6 -21.7% Cephalosporins 208.4 204.1 -2.1% Penicillins 244.7 191.1 -21.9% Extended-spectrum penicillins 142 118.4 -16.6% Quinolones 25.9 23.3 -10% Carbapenems 10.9 9.6 -12% Conclusion Requiring antimicrobial orders to list an indication resulted in decreased overall use. Larger prospective studies should be done to confirm the generalizability of these results. Disclosures All authors: No reported disclosures.

Objectives To evaluate the safety and tolerability of treatment with levetiracetam and determine the trough levels of levetiracetam in patients with traumatic brain injury (TBI) who are at high risk for posttraumatic epilepsy (PTE). Design Open-label, nonrandomized phase 2 study with 2 arms comparing levetiracetam treatment vs observation. Setting Two level 1 trauma centers. Patients A total of 422 participants 6 years or older with TBI who have a 20% risk for PTE were screened. Of these participants, 205 (48.6%) were eligible. A total of 126 participants were enrolled: 86 adults and 40 children. A total of 66 participants were in the treatment group (46 adults and 20 children), and a total of 60 participants were in the observation group (40 adults and 20 children). Participants presenting within 8 hours after TBI received treatment, and those presenting more than 8 to 24 hours after TBI did not. Intervention Treatment with levetiracetam (55 mg/kg/d) for 30 days starting within 8 hours after injury. Main outcome measures Number of adverse events, mood score, number of infections, trough level of levetiracetam, and PTE. Results Of the 66 participants treated with levetiracetam, 2 (3%) stopped treatment owing to toxicity (somnolence). The most common adverse events were fatigue, headache, and somnolence. Mood scores and number of infections did not differ between the treatment and observation groups. Mean trough levels of levetiracetam on days 2 to 30 ranged from 19.6 to 26.7 μg/mL. At 2 years, 13 of 86 adults (15.1%) and 1 of 40 children (2.5%) developed PTE. At 2 years, 5 of 46 treated adults (10.9%) and 8 of 40 untreated adults (20.0%) developed PTE (relative risk, 0.47; P=.18). Conclusion Treatment with 55 mg/kg/d of levetiracetam (a dose with an antiepileptogenic effect on animals) for patients with TBI at risk for PTE is safe and well tolerated, with plasma levels similar to those in animal studies. The findings support further evaluation of levetiracetam treatment for the prevention of PTE. Trial registration clinicaltrials.gov Identifier: NCT01463033.

Locked-in syndrome (LIS) is the combination of quadriplegia and anarthria (inability to speak), with the preservation of consciousness. The majority of cases are caused by basilar artery occlusion leading to brainstem infarction in the ventral pons, yet numerous other etiologies have been described. The diagnosis of LIS is completely dependent on the physician's ability to know that these manifestations originate in the brainstem and the posterior circulation that supplies it. This knowledge hinges on the ability of the examining physician to conduct a rapid, yet appropriately thorough neurologic examination. With recent advances in interventional neuroradiology leading to improved patient outcomes, LIS has evolved into a critical, time-dependent diagnosis. Herein, we present the case of a male patient who initially presented to the emergency department of a community hospital with coma of unknown cause. By presenting this case and focusing on the importance of the occulomotor exam, we hope to help in the rapid identification and treatment of patients with LIS in the emergency room and avoid outcomes similar to that of our patient.

Following our paper given at the IFIP Congress 71, another progres report is presented of our ongoing research efforts aimed at human decision making under uncertainty and risk. We have studied many aspects of human and machine learning processes, inductive and deductive inference making methods, how heuristic rules are formed and optimized by human players, and how similar results can be arrived at by machines. Although the investigations have been within the general framework of the game of Poker. our findings are considered to have a rather wide range of applicability. Also, the complex information processing system at hand incorporates both normative and descriptive theories of certain human behavior. Finally, the results of some empirical explorations are followed by an account of present and planned activities.