Training Robust T1-Weighted Magnetic Resonance Imaging Liver Segmentation Models Using Ensembles of Datasets with Different Contrast Protocols and Liver Disease Etiologies

Image segmentation of the liver is an important step in several treatments for liver cancer. However, manual segmentation at a large scale is not practical, leading to increasing reliance on deep learning models to automatically segment the liver. This manuscript develops a deep learning model to segment the liver on T1w MR images. We sought to determine the best architecture by training, validating, and testing three different deep learning architectures using a total of 819 T1w MR images gathered from six different datasets, both publicly and internally available. Our experiments compared each architecture's testing performance when trained on data from the same dataset via 5-fold cross validation to its testing performance when trained on all other datasets. Models trained using nnUNet achieved mean Dice-Sorensen similarity coefficients > 90% when tested on each of the six datasets individually. The performance of these models suggests that an nnUNet liver segmentation model trained on a large and diverse collection of T1w MR images would be robust to potential changes in contrast protocol and disease etiology.

Single-center Outcomes After Liver Transplantation With SARS-CoV-2-Positive Donors: An Argument for Increased Utilization

Background

The COVID-19 pandemic has led to an increase in SARS-CoV-2-test positive potential organ donors. The benefits of life-saving liver transplantation (LT) must be balanced against the potential risk of donor-derived viral transmission. Although emerging evidence suggests that the use of COVID-19-positive donor organs may be safe, granular series thoroughly evaluating safety are still needed. Results of 29 consecutive LTs from COVID-19-positive donors at a single center are presented here.

Methods

A retrospective cohort study of LT recipients between April 2020 and December 2022 was conducted. Differences between recipients of COVID-19-positive (n = 29 total; 25 index, 4 redo) and COVID-19-negative (n = 472 total; 454 index, 18 redo) deceased donor liver grafts were compared.

Results

COVID-19-positive donors were significantly younger (P = 0.04) and had lower kidney donor profile indices (P = 0.04) than COVID-19-negative donors. Recipients of COVID-19-positive donor grafts were older (P = 0.04) but otherwise similar to recipients of negative donors. Donor SARS-CoV-2 infection status was not associated with a overall survival of recipients (hazard ratio, 1.11; 95% confidence interval, 0.24-5.04; P = 0.89). There were 3 deaths among recipients of liver grafts from COVID-19-positive donors. No death seemed virally mediated because there was no qualitative association with peri-LT antispike antibody titers, post-LT prophylaxis, or SARS-CoV-2 variants.

Conclusions

The utilization of liver grafts from COVID-19-positive donors was not associated with a decreased overall survival of recipients. There was no suggestion of viral transmission from donor to recipient. The results from this large single-center study suggest that COVID-19-positive donors may be used safely to expand the deceased donor pool.

Effectiveness of virtual teaching of diagnostic and interventional imaging fundamentals to Egyptian medical students: an analytical cross-sectional study

Background

There is a worldwide deficit in teaching and training in the field of radiology for undergraduate medical students. This educational gap is prominent in many medical schools as most radiology curricula are a part of other specialty trainings, usually provided by non-radiologists. After COVID-19 pandemic, there was an increased trend in online education. However, questions have been raised about the efficacy and acceptance of online education. We developed a course on the principles of radiology and medical imaging basics to target Egyptian medical students. We then assessed the impact of these educational videos through several online surveys. Our "The Principles of Radiology Online Course" was delivered to students at various Egyptian medical schools; it was a prerecorded series composed of nine sessions, and each session followed the sequence of a pre-test, video, and post-test. There was a final survey to assess the overall feedback. Finally, we analyzed the results to give insight onto how teaching radiology through online lectures can help build better physicians.

Results

Among various medical schools around Egypt, 1396 Egyptian medical students joined this cohort. Cohort population percentage was 56% female and 44% male. Ninety-eight percent of the students agreed that this program increased their understanding of radiology. Eighty-four percent of the students found the platform friendly and easy to use. Seventy-nine percent found these webinars were more convenient compared to in-person education. Statistical significance (p-value < 0.05) was achieved in all sessions after comparing students’ pre and post-test scores, and in students’ confidence and knowledge level before and after the course.

Conclusions

Radiology is an underrepresented subject for a lot of medical students. Online radiology webinars have proven to be a promising method of teaching medical students key medical imaging concepts. An online course of radiology basics and principles can help improve a medical student’s knowledge and enhance overall future patient care.

Impact of unemployment on cardiovascular mortality in united states: a nationwide county-level analysis 2010–2019

Background

Unemployment has been linked with a myriad of adverse health outcomes; however, its population-level impact on cardiovascular mortality (CVM), particularly amongst various demographic subgroups, remains understudied.

Purpose

To determine the impact of county unemployment levels on CVM rates, in overall and between different demographic subgroups.

Methods

We utilized the CDC WONDER database tool to retrieve county-level CVM rates for U.S. counties between 2010 and 2019. The County Health Rankings project was used to retrieve data on unemployment levels in each county as well as other characteristics used in an adjusted multivariate model. Generalized linear mixed models using Poisson regression were used to estimate the impact of unemployment on county-level CVM using relative (incidence rate ratios; IRR) and absolute (additional yearly deaths; AYD) measures.

Results

From 2010 to 2019, a total of 2904 U.S. counties (64.2% white; 50.81% female) with data available on CVM and unemployment levels were analyzed. In a multivariate model adjusted for demographic composition, CV risk, socioeconomic, environmental, and healthcare-access factors, unemployment was significantly associated with higher levels of CVM (IRR: 1.026; 95% CI: 1.018 to 1.033; 6.00 AYD). The relative impact of unemployment was strongest in elderly Blacks (IRR: 1.051; 95% CI: 1.029 to 1.074), middle-aged whites (IRR: 1.050; 95% CI: 1.032 to 1.067), and middle-aged females (IRR: 1.046; 95% CI: 1.018 to 1.075). The absolute impact of unemployment was highest in elderly Blacks (AYD: 94.70), elderly Whites (AYD: 35.30), and elderly females (AYD: 32.70). On a relative basis, the impact was more pronounced in the middle-aged (IRR: 1.030; 95% CI: 1.015 to 1.044) compared to the elderly (IRR: 1.022; 95% CI: 1.014 to 1.030), females (IRR: 1.026; 95% CI: 1.017 to 1.036) compared to males (IRR: 1.022; 95% CI: 1.014 to 1.031), and Blacks (IRR: 1.036; 95% CI: 1.016 to 1.057) compared to Whites (IRR: 1.030; 95% CI: 1.022 to 1.038).

Conclusion(s)

Unemployment is significantly associated with county-level CVM, and this impact is most pronounced in vulnerable demographic subgroups, namely females and Blacks. Efforts to reduce unemployment levels may significantly lower the burden of cardiovascular disease, particularly in groups most strongly affected by health disparities.

Funding Acknowledgement

Type of funding sources: None.

Impact of sleep insufficiency on cardiovascular mortality in United States: a nationwide county-level analysis 2016–2019

Background

Sleep plays an integrated role in health maintenance including cardiovascular (CV) health. Sleep Insufficiency (SI) is a common modifiable risk condition that is strongly linked to major adverse CV events and mortality. However, data on the overall impact and related disparities of SI on CV mortality (CVM), at nationwide level and within different patient groups, are scarce and uncertain.

Purpose

Herein, we aim to study the independent relationship between county level SI and CVM in overall population and within various age, sex, and race/ethnic subgroups.

Methods

Using the Behavioral risk Factors Surveillance System (BRFSS), SI county levels were assessed as the percentage of adults who report fewer than the recommended level of optimal sleep duration (&lt;7 hours). Age-adjusted CVM rates (ACVM) between 2016 to 2019, were obtained using wide-ranging online data for epidemiologic research tool of Centers for Disease and Prevention (CDC). BRFSS, CDC diabetes interactive atlas, census population estimates, environmental public network, and county health rankings databases, were utilized to acquire county data of demographics, CV risk, socio-environmental, and health care access factors. Poisson multivariate generalized linear mixed models were employed to assess incidence rate ratios (IRR). To evaluate the absolute impact of SI on ACVM, additional yearly deaths per 100,000 individuals (AYD) were calculated.

Results

Among 3143 US counties, 2853 counties who had data on SI and ACVM, were analyzed. Of 321,625,744 residents (50.8% women, 12.4% non-Hispanic blacks, 15% aged ≥65) lived at 2853 US counties in 2016, total 3,408,047 (1.1%) CV deaths occurred between 2016–2019. In fully adjusted analysis*, SI significantly associated with overall ACVM (IRR: 1.021; 95% CI: 1.013 to 1.029), that translated to 4.6 AYD. In additional subgroup analysis, SI significantly associated with higher ACVM among middle aged adults [45 to 64] (IRR: 1.024; 95% CI: 1.010 to 1.038), elderly [≥65] (IRR: 1.022; 95% CI: 1.014 to 1.030), males (IRR: 1.019; 95% CI: 1.010 to 1.028), females (IRR: 1.023; 95% CI: 1.013 to 1.033), and in non-Hispanic whites (IRR: 1.024; 95% CI: 1.016 to 1.033). Notably, this association remained significant in the (≥65) aged subgroup of males, and females, as well as in both age subgroups of the non-Hispanic whites, (Figure).

Conclusion

County level SI is robustly related to high ACVM, and that relationship is most apparent amongst both age and sex subgroups as well as non-Hispanic whites. Moreover, this association is significantly independent of potential confounders that have a plausible association with CVM, such as demographics, socioeconomic, environmental, health care access, and cardiovascular risk factors. Therefore, tailored population-level strategies to promote healthy sleep pattern and reduce the prevalence of SI, are imperative for preventing CVM, especially in the most impacted communities and patient subgroups.

Funding Acknowledgement

Type of funding sources: None.

Mastocytosis-A Review of Disease Spectrum with Imaging Correlation

Simple Summary

In this review will discuss the clinical presentation, pathophysiology, and role of imaging in detection and extent estimation of the systemic involvement of the disease, in addition to demonstration of appearance on varying imaging modalities. Familiarity with the potential imaging findings associated with mastocytosis can aid in early disease diagnosis and classification and accordingly can lead directing further work up and better management.

Abstract

Mastocytosis is a rare disorder due to the abnormal proliferation of clonal mast cells. Mast cells exist in most tissues, mature in situ from hematopoietic stem cells and develop unique characteristics of local effector cells. Mastocytosis develops by activation mutation of the KIT surface receptor which is involved in the proliferation of a number of cell lines such as mast cells, germ cells, melanocytes, and hematopoietic cells. It manifests as two main categories: cutaneous mastocytosis and systemic mastocytosis. Imaging can play an important role in detection and characterization of the disease manifestation, not only by radiography and bone scans, but also magnetic resonance imaging and computed tomography, which can be more sensitive in the assessment of distinctive disease patterns. Radiologists should be aware of various appearances of this disease to better facilitate diagnosis and patient management. Accordingly, this review will discuss the clinical presentation, pathophysiology, and role of imaging in detection and extent estimation of the systemic involvement of the disease, in addition to demonstration of appearance on varying imaging modalities. Familiarity with the potential imaging findings associated with mastocytosis can aid in early disease diagnosis and classification and accordingly can lead directing further work up and better management.

Betrixaban for first-line venous thromboembolism prevention in acute medically ill patients with risk factors for venous thromboembolism

INTRODUCTION

Compared to other direct oral anticoagulants, betrixaban has a longer half-life, smaller peak-trough variance, minimal renal clearance, and minimal hepatic Cytochrome P (CYP) metabolism. The Acute Medically Ill VTE Prevention with Extended Duration Betrixaban (APEX) trial evaluated the efficacy and safety of extended duration betrixaban compared to standard duration enoxaparin in acutely ill hospitalized patients. Areas covered: This article describes the role of betrixaban in the prevention of venous thromboembolism (VTE) in acutely ill medical patients. This article provides a consolidated summary of the primary APEX study findings as well as prespecified and exploratory substudies. This article also provides a review of the results of studies in which other direct factor Xa inhibitors have been evaluated in an extended duration regimen in this patient population. Expert commentary: While previous agents have demonstrated that extended duration VTE prophylaxis can be efficacious, betrixaban is the first agent to demonstrate efficacy without an increase in major bleeding. The totality of the data from the APEX trial supports extended duration betrixaban for VTE prophylaxis in the acute medically ill patient population. As such, betrixaban has been approved in the USA for extended VTE prophylaxis in at-risk acute medically ill patients.