Local Assessment and Small Bowel Crohn's Disease Severity Scoring using AI.

RATIONALE AND OBJECTIVES: We present a machine learning and computer vision approach for a localized, automated, and standardized scoring of Crohn's disease (CD) severity in the small bowel, overcoming the current limitations of manual measurements CT enterography (CTE) imaging and qualitative assessments, while also considering the complex anatomy and distribution of the disease. MATERIALS AND METHODS: Two radiologists introduced a severity score and evaluated disease severity at 7.5 mm intervals along the curved planar reconstruction of the distal and terminal ileum using 236 CTE scans. A hybrid model, combining deep-learning, 3-D CNN, and Random Forest model, was developed to classify disease severity at each mini-segment. Precision, sensitivity, weighted Cohen's score, and accuracy were evaluated on a 20% hold-out test set. RESULTS: The hybrid model achieved precision and sensitivity ranging from 42.4% to 84.1% for various severity categories (normal, mild, moderate, and severe) on the test set. The model's Cohen's score (κ = 0.83) and accuracy (70.7%) were comparable to the inter-observer agreement between experienced radiologists (κ = 0.87, accuracy = 76.3%). The model accurately predicted disease length, correlated with radiologist-reported disease length (r = 0.83), and accurately identified the portion of total ileum containing moderate-to-severe disease with an accuracy of 91.51%. CONCLUSION: The proposed automated hybrid model offers a standardized, reproducible, and quantitative local assessment of small bowel CD severity and demonstrates its value in CD severity assessment.

A deep learning-based pipeline for developing multi-rib shape generative model with populational percentiles or anthropometrics as predictors.

Rib cross-sectional shapes (characterized by the outer contour and cortical bone thickness) affect the rib mechanical response under impact loading, thereby influence the rib injury pattern and risk. A statistical description of the rib shapes or their correlations to anthropometrics is a prerequisite to the development of numerical human body models representing target demographics. Variational autoencoders (VAE) as anatomical shape generators remain to be explored in terms of utilizing the latent vectors to control or interpret the representativeness of the generated results. In this paper, we propose a pipeline for developing a multi-rib cross-sectional shape generative model from CT images, which consists of the achievement of rib cross-sectional shape data from CT images using an anatomical indexing system and regular grids, and a unified framework to fit shape distributions and associate shapes to anthropometrics for different rib categories. Specifically, we collected CT images including 3193 ribs, surface regular grid is generated for each rib based on anatomical coordinates, the rib cross-sectional shapes are characterized by nodal coordinates and cortical bone thickness. The tensor structure of shape data based on regular grids enable the implementation of CNNs in the conditional variational autoencoder (CVAE). The CVAE is trained against an auxiliary classifier to decouple the low-dimensional representations of the inter- and intra- variations and fit each intra-variation by a Gaussian distribution simultaneously. Random tree regressors are further leveraged to associate each continuous intra-class space with the corresponding anthropometrics of the subjects, i.e., age, height and weight. As a result, with the rib class labels and the latent vectors sampled from Gaussian distributions or predicted from anthropometrics as the inputs, the decoder can generate valid rib cross-sectional shapes of given class labels (male/female, 2nd to 11th ribs) for arbitrary populational percentiles or specific age, height and weight, which paves the road for future biomedical and biomechanical studies considering the diversity of rib shapes across the population.

Independent Associations of Aortic Calcification with Cirrhosis and Liver Related Mortality in Veterans with Chronic Liver Disease.

INTRODUCTION: Abdominal aortic calcifications (AAC) are incidentally found on medical imaging and useful cardiovascular burden approximations. The Morphomic Aortic Calcification Score (MAC) leverages automated deep learning methods to quantify and score AACs. While associations of AAC and non-alcoholic fatty liver disease (NAFLD) have been described, relationships of AAC with other liver diseases and clinical outcome are sparse. This study's purpose was to evaluate AAC and liver-related death in a cohort of Veterans with chronic liver disease (CLD). METHODS: We utilized the VISN 10 CLD cohort, a regional cohort of Veterans with the three forms of CLD: NAFLD, hepatitis C (HCV), alcohol-associated (ETOH), seen between 2008 and 2014, with abdominal CT scans (n = 3604). Associations between MAC and cirrhosis development, liver decompensation, liver-related death, and overall death were evaluated with Cox proportional hazard models. RESULTS: The full cohort demonstrated strong associations of MAC and cirrhosis after adjustment: HR 2.13 (95% CI 1.63, 2.78), decompensation HR 2.19 (95% CI 1.60, 3.02), liver-related death HR 2.13 (95% CI 1.46, 3.11), and overall death HR 1.47 (95% CI 1.27, 1.71). These associations seemed to be driven by the non-NAFLD groups for decompensation and liver-related death [HR 2.80 (95% CI 1.52, 5.17; HR 2.34 (95% CI 1.14, 4.83), respectively]. DISCUSSION: MAC was strongly and independently associated with cirrhosis, liver decompensation, liver-related death, and overall death. Surprisingly, stratification results demonstrated comparable or stronger associations among those with non-NAFLD etiology. These findings suggest abdominal aortic calcification may predict liver disease severity and clinical outcomes in patients with CLD.

Extracorporeal Life Support Use in Mixed Distributive-Obstructive Shock following an Electrical Injury: A Case Report.

Electrical burn injuries can be catastrophic, threatening severe disability or mortality. We present a patient who suffered from electrical shock, requiring bilateral above knee amputations, right trans-radial amputation, renal replacement therapy, and veno-arterial extracorporeal life support (VA ECLS) therapy. While there exist reports of cases that have demonstrated the potential use of ECLS in burn patients with cardiogenic shock or acute respiratory distress syndrome (ARDS), this is a unique case of VA ECLS use for an electrical injury patient who developed mixed distributive-obstructive shock secondary to pulmonary embolism and sepsis. Given the wide variety of morbidities that can result from electrical burns, VA ECLS is a promising tool for those who require cardiopulmonary support refractory to traditional measures.

Artificial Intelligence for Quantifying Cumulative Small Bowel Disease Severity on CT-Enterography in Crohn's Disease.

INTRODUCTION: Assessing the cumulative degree of bowel injury in ileal Crohn's disease (CD) is difficult. We aimed to develop machine learning (ML) methodologies for automated estimation of cumulative ileal injury on computed tomography-enterography (CTE) to help predict future bowel surgery. METHODS: Adults with ileal CD using biologic therapy at a tertiary care center underwent ML analysis of CTE scans. Two fellowship-trained radiologists graded bowel injury severity at granular spatial increments along the ileum (1 cm), called mini-segments. ML segmentation methods were trained on radiologist grading with predicted severity and then spatially mapped to the ileum. Cumulative injury was calculated as the sum (S-CIDSS) and mean of severity grades along the ileum. Multivariate models of future small bowel resection were compared with cumulative ileum injury metrics and traditional bowel measures, adjusting for laboratory values, medications, and prior surgery at the time of CTE. RESULTS: In 229 CTE scans, 8,424 mini-segments underwent analysis. Agreement between ML and radiologists injury grading was strong (κ = 0.80, 95% confidence interval 0.79-0.81) and similar to inter-radiologist agreement (κ = 0.87, 95% confidence interval 0.85-0.88). S-CIDSS (46.6 vs 30.4, P = 0.0007) and mean cumulative injury grade scores (1.80 vs 1.42, P < 0.0001) were greater in CD biologic users that went to future surgery. Models using cumulative spatial metrics (area under the curve = 0.76) outperformed models using conventional bowel measures, laboratory values, and medical history (area under the curve = 0.62) for predicting future surgery in biologic users. DISCUSSION: Automated cumulative ileal injury scores show promise for improving prediction of outcomes in small bowel CD. Beyond replicating expert judgment, spatial enterography analysis can augment the personalization of bowel assessment in CD.

Reference distributions of aortic calcification and association with Framingham risk score.

Evidence supporting aortic calcification as a leverageable cardiovascular risk factor is rapidly growing. Given aortic calcification's potential as a clinical correlate, we assessed granular vertebral-indexed calcification measurements of the abdominal aorta in a well curated reference population. We evaluated the relationship of aortic calcification measurements with Framingham risk scores. After exclusion, 4073 participants from the Reference Analytic Morphomic Population with varying vertebral levels were included. The percent of the aortic wall calcified was used to assess calcification burden at the L1-L4 levels. Descriptive statistics of participants, sex-specific vertebral indexed calcification measurements, relational plots, and relevant associations are reported. Mean aortic attenuation was higher in female than male participants. Overall, mean aortic calcium was higher with reference to inferior abdominal aortic measurements and demonstrated significant differences across all abdominal levels [L3 Area (mm[Formula: see text]): Females 6.34 (sd 16.60), Males 6.23 (sd 17.21); L3 Volume (mm[Formula: see text]): Females 178.90 (sd 474.19), Males 195.80 (sd 547.36); Wall Calcification (%): Females (L4) 6.97 (sd 16.03), Males (L3) 5.46 (13.80)]. Participants with elevated calcification had significantly higher Framingham risk scores compared to participants with normal calcification scores. Opportunistically measuring aortic calcification may inform further cardiovascular risk assessment and enhance cardiovascular event surveillance efforts.

Sarcopenia provides extra value outside the PULP score for predicting mortality in older patients with perforated peptic ulcers.

BACKGROUND: Perforated peptic ulcer (PPU) remains challenging surgically due to its high mortality, especially in older individuals. Computed tomography (CT)-measured skeletal muscle mass is a effective predictor of the surgical outcomes in older patients with abdominal emergencies. The purpose of this study is to assess whether a low CT-measured skeletal muscle mass can provide extra value in predicting PPU mortality. METHODS: This retrospective study enrolled older (aged ≥ 65 years) patients who underwent PPU surgery. Cross-sectional skeletal muscle areas and densities were measured by CT at L3 and patient-height adjusted to obtain the L3 skeletal muscle gauge (SMG). Thirty-day mortality was determined with univariate, multivariate and Kaplan-Meier analysis. RESULTS: From 2011 to 2016, 141 older patients were included; 54.8% had sarcopenia. They were further categorized into the PULP score ≤ 7 (n=64) or PULP score > 7 group (n=82). In the former, there was no significant difference in 30-day mortality between sarcopenic (2.9%) and nonsarcopenic patients (0%; p=1.000). However, in the PULP score > 7 group, sarcopenic patients had a significantly higher 30-day mortality (25.5% vs. 3.2%, p=0.009) and serious complication rate (37.3% vs. 12.9%, p=0.017) than nonsarcopenic patients. Multivariate analysis showed that sarcopenia was an independent risk factor for 30-day mortality in patients in the PULP score > 7 group (OR: 11.05, CI: 1.03-118.7). CONCLUSION: CT scans can diagnose PPU and provide physiological measurements. Sarcopenia, defined as a low CT-measured SMG, provides extra value in predicting mortality in older PPU patients.

Tandem use of gastroesophageal resuscitative occlusion of the aorta followed by resuscitative endovascular balloon occlusion of the aorta in a lethal liver laceration model.

BACKGROUND: Gastroesophageal resuscitative occlusion of the aorta (GROA) has been shown effective in creating zone II aortic occlusion capable of temporarily improving survival in animal models of lethal noncompressible torso hemorrhage. In this study, tandem application of GROA transitioning to resuscitative endovascular balloon occlusion of the aorta (REBOA) is explored to demonstrate feasibility as a potential point-of-injury bridge to more advanced care, using a swine model of lethal abdominal hemorrhage. METHODS: Swine (n = 19) were anesthetized, instrumented, and subjected to a combination of controlled and uncontrolled hemorrhage from a grade-V liver laceration. Animals were designated as intervention (n = 9; GROA to REBOA) or control (n = 10), for 60 minutes. Following intervention, devices were deactivated, and animals received blood and crystalloid resuscitation. Animals were monitored for 4 hours. RESULTS: Injury resulted in onset of class IV shock in all animals with a mean arterial pressure (SD) of 24.5 (4.11) mm Hg at the start of intervention. Nine of 10 controls died during the intervention period with a median (interquartile) survival time of 8.5 (9.25) minutes. All animals receiving the intervention survived both the 60-minute intervention period demonstrating a significant survival improvement ( p = 0.0007). Transition from GROA to REBOA was successful in all animals with a transition time ranging from 30 to 90 seconds. Mean arterial pressure significantly improved in animals receiving GROA to REBOA for the duration of intervention, regardless of the method of aortic occlusion, with a range of 70.9 (16.04) mm Hg to 101.1 (15.3) mm Hg. Additional hemodynamics, metrics of shock, and oxygenation remained stable during intervention. CONCLUSION: Less invasive technologies such as GROA may present an opportunity to control noncompressible torso hemorrhage more rapidly, with a subsequent transition to more advanced care such as REBOA.

Variation in aorta attenuation in contrast-enhanced CT and its implications for calcification thresholds.

BACKGROUND: CT contrast media improves vessel visualization but can also confound calcification measurements. We evaluated variance in aorta attenuation from varied contrast-enhancement scans, and quantified expected plaque detection errors when thresholding for calcification. METHODS: We measured aorta attenuation (AoHU) in central vessel regions from 10K abdominal CT scans and report AoHU relationships to contrast phase (non-contrast, arterial, venous, delayed), demographic variables (age, sex, weight), body location, and scan slice thickness. We also report expected plaque segmentation false-negative errors (plaque pixels misidentified as non-plaque pixels) and false-positive errors (vessel pixels falsely identified as plaque), comparing a uniform thresholding approach and a dynamic approach based on local mean/SD aorta attenuation. RESULTS: Females had higher AoHU than males in contrast-enhanced scans by 65/22/20 HU for arterial/venous/delayed phases (p < 0.001) but not in non-contrast scans (p > 0.05). Weight was negatively correlated with AoHU by 2.3HU/10kg but other predictors explained only small portions of intra-cohort variance (R2 < 0.1 in contrast-enhanced scans). Average AoHU differed by contrast phase, but considerable overlap was seen between distributions. Increasing uniform plaque thresholds from 130HU to 200HU/300HU/400HU produces respective false-negative plaque content losses of 35%/60%/75% from all scans with corresponding false-positive errors in arterial-phase scans of 95%/60%/15%. Dynamic segmentation at 3SD above mean AoHU reduces false-positive errors to 0.13% and false-negative errors to 8%, 25%, and 70% in delayed, venous, and arterial scans, respectively. CONCLUSION: CT contrast produces heterogeneous aortic enhancements not readily determined by demographic or scan protocol factors. Uniform CT thresholds for calcified plaques incur high rates of pixel classification errors in contrast-enhanced scans which can be minimized using dynamic thresholds based on local aorta attenuation. Care should be taken to address these errors and sex-based biases in baseline attenuation when designing automatic calcification detection algorithms intended for broad use in contrast-enhanced CTs.

A GAN based approach for inferring progression trajectories of costal cartilage calcification from cross-sectional data at image level.

BACKGROUND: Costal cartilage calcification (CCC) increases with age and presents differently for men and women. In individuals, however, the cross-sectional studies that show such trends do not reveal the geometric trajectories through which calcification might accumulate across a lifetime. Generative adversarial networks have the potential to reveal such trajectories from cross-sectional data by learning population trends and synthesizing individualized images at progressive levels of calcification. METHODS: Chest wall mid-surface CT images with normalized cartilage morphologies were produced for 379 subjects aged 6 to 90, and labeled by sex and calcification severity. A conditional GAN with added loss terms to favor one-way accumulation of CCC was trained using organized image batches. GAN performance was assessed by comparing the distributions of images between the training and synthetic groups. RESULTS: Synthetic images generated from a common seed for a given sex and at successive calcification severity levels showed incremental and regional growth of calcification sites. CCC patterns for synthetic male and female images matched known sex-based differences, and individual CCC growth in synthetic images was consistent with previously observed population trends. These trends in the synthetic images were also quantified by structural similarity scores. Synthetic images generated from different input seeds further showed individual variance in specific regions and trajectories of CCC accumulation. CONCLUSION: This study inferred individual progression of CCC accumulation from uncalcified to severely calcified using cross-sectional image data. This information can inform computational models of the changing chest wall biomechanics with age, and the GAN-based technique shows potential for inferring longitudinal data from population trends in other clinical areas.

Healthy US population reference values for CT visceral fat measurements and the impact of IV contrast, HU range, and spinal levels.

Measurements of visceral adipose tissue cross-sectional area and radiation attenuation from computed tomography (CT) scans provide useful information about risk and mortality. However, scan protocols vary, encompassing differing vertebra levels and utilizing differing phases of contrast enhancement. Furthermore, fat measurements have been extracted from CT using different Hounsfield Unit (HU) ranges. To our knowledge, there have been no large studies of healthy cohorts that reported reference values for visceral fat area and radiation attenuation at multiple vertebra levels, for different contrast phases, and using different fat HU ranges. Two-phase CT scans from 1,677 healthy, adult kidney donors (age 18-65) between 1999 and 2017, previously studied to determine healthy reference values for skeletal muscle measures, were utilized. Visceral adipose tissue cross-sectional area (VFA) and radiation attenuation (VFRA) measures were quantified using axial slices at T10 through L4 vertebra levels. T-tests were used to compare males and females, while paired t-tests were conducted to determine the effect (magnitude and direction) of (a) contrast enhancement and (b) different fat HU ranges on each fat measure at each vertebra level. We report the means, standard deviations, and effect sizes of contrast enhancement and fat HU range. Male and female VFA and VFRA were significantly different at all vertebra levels in both contrast and non-contrast scans. Peak VFA was observed at L4 in females and L2 in males, while peak VFRA was observed at L1 in both females and males. In general, non-contrast scans showed significantly greater VFA and VFRA compared to contrast scans. The average paired difference due to contrast ranged from 1.6 to - 8% (VFA) and 3.2 to - 3.0% (VFRA) of the non-contrast value. HU range showed much greater differences in VFA and VFRA than contrast. The average paired differences due to HU range ranged from - 5.3 to 22.2% (VFA) and - 5.9 to 13.6% (VFRA) in non-contrast scans, and - 4.4 to 20.2% (VFA) and - 4.1 to 12.6% (VFRA) in contrast scans. The - 190 to - 30 HU range showed the largest differences in both VFA (10.8% to 22.2%) and VFRA (7.6% to 13.6%) compared to the reference range (- 205 to - 51 HU). Incidentally, we found that differences in lung inflation result in very large differences in visceral fat measures, particularly in the thoracic region. We assessed the independent effects of contrast presence and fat HU ranges on visceral fat cross-sectional area and mean radiation attenuation, finding significant differences particularly between different fat HU ranges. These results demonstrate that CT measurements of visceral fat area and radiation attenuation are strongly dependent upon contrast presence, fat HU range, sex, breath cycle, and vertebra level of measurement. We quantified contrast and non-contrast reference values separately for males and females, using different fat HU ranges, for lumbar and thoracic CT visceral fat measures at multiple vertebra levels in a healthy adult US population.

Muscle mass affects paclitaxel systemic exposure and may inform personalized paclitaxel dosing.

AIMS: Patients with low muscle mass have increased risk of paclitaxel-induced peripheral neuropathy, which is dependent on systemic paclitaxel exposure. Dose optimization may be feasible through the secondary use of radiologic data for body composition. The objective of this study was to interrogate morphomic parameters as predictors of paclitaxel pharmacokinetics to identify alternative dosing strategies that may improve treatment outcomes. METHODS: This was a secondary analysis of female patients with breast cancer scheduled to receive 80 mg/m2 weekly paclitaxel infusions. Paclitaxel was measured at the end of initial infusion to estimate maximum concentration (Cmax ). Computed tomography (CT) scans were used to measure 29 body composition features for inclusion in pharmacokinetic modelling. Monte Carlo simulations were performed to identify infusion durations that limit the probability of exceeding Cmax > 2885 ng/mL, which was selected based on prior work linking this to an unacceptable risk of peripheral neuropathy. RESULTS: Thirty-nine patients were included in the analysis. The optimal model was a two-compartment pharmacokinetic model with T11 skeletal muscle area as a covariate of paclitaxel volume of distribution (Vd). Simulations suggest that extending infusion of the standard paclitaxel dose from 1 hour to 2 and 3 hours in patients who have skeletal muscle area 4907-7080 mm2 and <4907 mm2 , respectively, would limit risk of Cmax > 2885 ng/mL to <50%, consequently reducing neuropathy, while marginally increasing overall systemic paclitaxel exposure. CONCLUSION: Extending paclitaxel infusion duration in ~25% of patients who have low skeletal muscle area is predicted to reduce peripheral neuropathy while maintaining systemic exposure, suggesting that personalizing paclitaxel dosing based on body composition may improve treatment outcomes.

Gastroesophageal resuscitative occlusion of the aorta prolongs survival in a lethal liver laceration model.

BACKGROUND: Noncompressible torso hemorrhage management remains a challenge especially in the prehospital setting. We evaluated a device designed to occlude the aorta from the stomach (gastroesophageal resuscitative occlusion of the aorta [GROA]) for its ability to stop hemorrhage and improve survival in a swine model of lethal liver laceration and compared its performance to resuscitative endovascular balloon occlusion of the aorta (REBOA) and controls. METHODS: Swine (n = 24) were surgically instrumented and a 30% controlled arterial hemorrhage over 20 minutes was followed by liver laceration. Animals received either GROA, REBOA, or control (no treatment) for 60 minutes. Following intervention, devices were deactivated, and animals received whole blood and crystalloid resuscitation. Animals were monitored for an additional 4 hours. RESULTS: The liver laceration resulted in the onset of class IV shock. Mean arterial blood pressure (MAP) (standard deviation) decreased from 84.5 mm Hg (11.69 mm Hg) to 27.1 mm Hg (5.65 mm Hg) at the start of the intervention. Seven of eight control animals died from injury prior to the end of the intervention period with a median survival (interquartile) time of 10.5 minutes (12 minutes). All GROA and REBOA animals survived the duration of the intervention period (60 minutes) with median survival times of 86 minutes (232 minutes) and 79 minutes (199 minutes) after resuscitation, respectively. The GROA and REBOA animals experienced a significant improvement in survival compared with controls (p = 0.01). Resuscitative endovascular balloon occlusion of the aorta resulted in higher MAP at the end of intervention 114.6 mm Hg (22.9 mm Hg) compared with GROA 88.2 mm Hg (18.72 mm Hg) (p = 0.024), as well as increased lactate compared with GROA 13.2 meq·L-1 (1.56 meq·L-1) versus 10.5 meq·L-1 (1.89 meq·L-1) (p = 0.028). Histological examination of the gastric mucosa in surviving animals revealed mild ischemic injury from both GROA and REBOA. CONCLUSION: The GROA and REBOA devices were both effective at temporarily stanching lethal noncompressible torso hemorrhage of the abdomen and prolonging survival.

Analytic Morphomics Are Related to Outcomes After Lung Volume Reduction Surgery.

:Lung volume reduction surgery continues to have a high morbidity despite National Emphysema Treatment Trial selection criteria. This study evaluated the association between analytic morphomics on chest computed tomography scans and outcomes after lung volume reduction surgery. In a retrospective review of 85 lung volume reduction surgery patients from 1998-2013, dorsal muscle group area, subcutaneous and visceral fat area, and bone mineral density were assessed using analytic morphomics. Lung density was divided into five levels of increasing density (Lung density 1, emphysema; 2, normal lung; 4-5, scarring). Outcomes including survival, hospital length of stay, readmission at 30 days, and pulmonary complications were analyzed using univariate and multivariable techniques. Pulmonary complications developed in 27.1% (23/85). Mortality at 90 days was 9.4% (8/85). On multivariable analysis, lower bone mineral density (Odds ratio 0.61; 95% confidence interval 0.39-0.95) was associated with decreased survival, longer length of stay (0.83; 0.77-0.89), and readmissions (0.39; 0.15-1.00). Higher lung density 5:lung density 2 volume (1.84; 1.05-3.23), possibly due to scarring, was associated with pulmonary complications and longer length of stay (1.32; 1.23-1.41) while lower subcutaneous fat area:height was associated with readmissions which may reflect decreased metabolic reserve (0.35; 0.13-0.93). Patients with signs of frailty including lower bone mineral density may be at increased risk of adverse outcomes including decreased survival after lung volume reduction surgery. The results of this hypothesis-generating study will need to be confirmed in larger, multicenter trials to determine whether analytic morphomics can improve risk stratification and patient selection.

A correction score to compare aortic calcification in contrast enhanced and non-contrast measurements from computed tomography scans.

BACKGROUND: Aortic wall calcification shows strong promise as a cardiovascular risk factor. While useful for visual enhancement of vascular tissue, enhancement creates heterogeneity between scans with and without contrast. We evaluated the relationship between aortic calcification in routine abdominal computed tomography scans (CT) with and without contrast. METHODS: Inclusion was limited to those with abdominal CT-scans with and without contrast enhancement within 120 days. Analytic Morphomics, a semi-automated computational image processing system, was used to provide standardized, granular, anatomically indexed measurements of aortic wall calcification from abdominal CT-scans. Aortic calcification area (ACA) and aortic wall calcification percent (ACP) and were the outcomes of interest. Multiple linear regression was used to evaluate the relationship of aortic measurements. Models were further controlled for age and sex. Stratification of measurements by vertebral level was also performed. RESULTS: A positive association was observed for non-contrast calcification in ACP ß 0.74 (95% CI 0.72, 0.76) and ACA ß 0.44 (95% 0.43, 0.45). Stratified results demonstrated the highest coefficient of determination at L2 for percent and L3 for area models [R2 0.91 (ACP) 0.74 (ACA)]. Adjusted lumber-level associations between non-contrast and contrast measurements ranged from (ß 0.69-0.82) in ACP and (ß 0.37-0.54) in ACA. CONCLUSION: A straightforward correction score for comparison of abdominal aortic calcification measurements in contrast-enhanced and non-contrast scans is discussed. Correction of aortic calcification from CT scans can reduce scan heterogeneity and will be instrumental in creating larger cardiovascular cohorts as well as cardiovascular risk surveillance programs.

Automated Measurements of Body Composition in Abdominal CT Scans Using Artificial Intelligence Can Predict Mortality in Patients With Cirrhosis.

Body composition measures derived from already available electronic medical records (computed tomography [CT] scans) can have significant value, but automation of measurements is needed for clinical implementation. We sought to use artificial intelligence to develop an automated method to measure body composition and test the algorithm on a clinical cohort to predict mortality. We constructed a deep learning algorithm using Google's DeepLabv3+ on a cohort of de-identified CT scans (n = 12,067). To test for the accuracy and clinical usefulness of the algorithm, we used a unique cohort of prospectively followed patients with cirrhosis (n = 238) who had CT scans performed. To assess model performance, we used the confusion matrix and calculated the mean accuracy of 0.977 ± 0.02 (0.975 ± 0.018 for the training and test sets, respectively). To assess for spatial overlap, we measured the mean intersection over union and mean boundary contour scores and found excellent overlap between the manual and automated methods with mean scores of 0.954 ± 0.030, 0.987 ± 0.009, and 0.948 ± 0.039 (0.983 ± 0.013 for the training and test set, respectively). Using these automated measurements, we found that body composition features were predictive of mortality in patients with cirrhosis. On multivariate analysis, the addition of body composition measures significantly improved prediction of mortality for patients with cirrhosis over Model for End-Stage Liver Disease alone (P < 0.001). Conclusion: The measurement of body composition can be automated using artificial intelligence and add significant value for incidental CTs performed for other clinical indications. This is proof of concept that this methodology could allow for wider implementation into the clinical arena.

Psoas Muscle Mass can Predict Postsurgical Outcomes in Patients Who Undergo Radical Cystectomy and Urinary Diversion Reconstruction.

OBJECTIVE: To morphometrically measure to muscle mass which may reflect physical components of frailty. Hence, we evaluated the association between L4 total psoas area (TPA) and operative outcome after radical cystectomy (RC) for bladder cancer. METHODS: In a retrospective single-center study, bladder cancer patients who underwent RC and urinary diversion between 2007 and 2012 were enrolled. TPA was evaluated in the cross-sectional imaging. The psoas muscles were normalized with the height. Male patients with a psoas mass index ≤7.4 cm2/m2 and female patients with a psoas mass index ≤5.2 cm2/m2 were classified as sarcopenic. Outcome measures were 30- and 90-day readmission and complications, and survival. Multivariable logistic and Cox proportional-hazards regression models were used to determine relevant predictors. RESULTS: The median age of the 441 participants and follow up time was 68 years (IQR 59-75) and 1.2 years (IQR 0.5-1.9), respectively. One hundred forty-three patients (32.4%) were sarcopenic. The 30-day readmission and the complication rates were 13.8% and 44.7%, respectively. The 90-day readmission and complication rates were 23.9% and 53.1%, respectively. The 1-year mortality rate was 11.6% (95%CI 8.7-15.4). Multivariable logistic regression analysis revealed an association between increased TPA and lower odds of 30-day complications after RC (OR 0.95, 95%CI 0.92-0.99, P = .02); similarly, an increase in TPA was of prognostic value, although not statistically significant in the multivariable model (P = .05) once adjusting for other patient factors. CONCLUSION: Sarcopenia predicted early complications and showed an informative trend for overall survival after RC, and thus may inform models predicting postsurgical outcomes.

Does a "Cushion Effect" Really Exist? A Morphomic Analysis of Vulnerable Road Users with Serious Blunt Abdominal Injury.

Introduction: The severity of injury from motor vehicle crashes (MVCs) depends on complex biomechanical factors, and the bodily features of the injured person account for some of these factors. By assuming that vulnerable road users (VRUs) have limited protection resulting from vehicles and safety equipment, the current study analyzed the characteristics of fat distribution measured by computed tomography (CT) imaging and investigated the existence of a "cushion effect" in VRUs. Materials and Methods: This retrospective study enrolled 592 VRUs involved in MVCs who underwent CT scans. Visceral fat area and subcutaneous fat cross-sectional area were measured and adjusted according to total body area (TBA) and are presented as the visceral fat ratio and the subQ fat ratio (subcutaneous fat ratio). Risk factors for serious abdominal injury (maximum abbreviated injury scale (MAISabd ≥ 3)) resulting from MVCs were determined by univariate and multivariate analysis. Results: MAISabd ≥ 3 was observed in 104 (17.6%) of the patients. The subQ fat ratio at the L4 vertebral level was significantly lower in the MAISabd ≥ 3 group than in the MAISabd < 3 group (24.9 ± 12.0 vs. 28.1 ± 11.9%; p = 0.015). A decreased L4 subQ fat ratio was associated with a higher risk for MAISabd ≥ 3 in multivariate analysis (odds ratio 0.063; 95% CI 0.008-0.509; p = 0.009). Conclusion: The current study supported the "cushion effect" theory, and protection was apparently provided by subcutaneous fat tissue. This concept may further improve vehicle and safety designation in the future.

Dermal Nanoemulsion Treatment Reduces Burn Wound Conversion and Improves Skin Healing in a Porcine Model of Thermal Burn Injury.

Burn wound progression is an inflammation-driven process where an initial partial-thickness thermal burn wound can evolve over time to a full-thickness injury. We have developed an oil-in-water nanoemulsion formulation (NB-201) containing benzalkonium chloride for use in burn wounds that is antimicrobial and potentially inhibits burn wound progression. We used a porcine burn injury model to evaluate the effect of topical nanoemulsion treatment on burn wound conversion and healing. Anesthetized swine received thermal burn wounds using a 25-cm2 surface area copper bar heated to 80°C. Three different concentrations of NB-201 (10, 20, or 40% nanoemulsion), silver sulfadiazine cream, or saline were applied to burned skin immediately after injury and on days 1, 2, 4, 7, 10, 14, and 18 postinjury. Digital images and skin biopsies were taken at each dressing change. Skin biopsy samples were stained for histological evaluation and graded. Skin tissue samples were also assayed for mediators of inflammation. Dermal treatment with NB-201 diminished thermal burn wound conversion to a full-thickness injury as determined by both histological and visual evaluation. Comparison of epithelial restoration on day 21 showed that 77.8% of the nanoemulsion-treated wounds had an epidermal injury score of 0 compared to 16.7% of the silver sulfadiazine-treated burns (P = .01). Silver sulfadiazine cream- and saline-treated wounds (controls) converted to full-thickness burns by day 4. Histological evaluation revealed reduced inflammation and evidence of skin injury in NB-201-treated sites compared to control wounds. The nanoemulsion-treated wounds often healed with complete regrowth of epithelium and no loss of hair follicles (NB-201: 4.8 ± 2.1, saline: 0 ± 0, silver sulfadiazine: 0 ± 0 hair follicles per 4-mm biopsy section, P < .05). Production of inflammatory mediators and sequestration of neutrophils were also inhibited by NB-201. Topically applied NB-201 prevented the progression of a partial-thickness burn wound to full-thickness injury and was associated with a concurrent decrease in dermal inflammation.

Predicting outcomes of abdominal surgical emergencies in the elderly population using a CT muscle gauge.

BACKGROUND: Frailty has been shown to be an independent negative predictor of surgical outcomes in geriatric patients. Traditional measurements of muscle strength and mass are impractical in emergency settings, and computed tomography (CT)-measured skeletal muscle mass has been proposed as an alternative. However, the cutoff values for low muscle mass are still unknown, and their impact on abdominal emergencies in the elderly population is unclear. METHODS: A total of 462 young trauma patients aged 18-40 years were analyzed to establish sex-specific reference cutoff values for the CT-measured muscle index (MI) and muscle gauge (MG) values. The impacts of low MI and MG values were investigated in 1192 elderly patients (aged ≥ 65 years) undergoing abdominal surgery. RESULTS: The sex-specific cutoff values for MI and MG were determined by adopting European Working Group on Sarcopenia in Older People 2 guidelines. The correlation between MG and aging was significantly stronger than that between MI and ageing. With regard to the MG, the L4 psoas muscle gauge (L4 PMG) was further investigated in an elderly cohort owing to its high predictive value and ease of use in the clinical setting. A low L4 PMG value was an independent risk factor for overall complications and mortality in elderly patients with abdominal emergencies. CONCLUSION: The current study was the largest study investigating the correlations between MG values and aging in the Asian population. A low L4 PMG value may help surgeons during preoperative decision making regarding geriatric patients with abdominal emergencies.