Effect of Attenuated Light Through Translucent Zirconia on the Interfacial Adaptation and Polymerization of Resin Cements.

PURPOSE: The first objective was to determine if dual-curing of resin cement with reduced light could affect interfacial adaptations of zirconia restoration. The second objective was to examine whether cement type and pretreatment method of universal adhesive affected interfacial adaptation. The final objective was to compare the polymerization degree of cement under different reduced-light conditions. MATERIALS AND METHODS: Inlay cavities were prepared on extracted third molars. Translucent zirconia restorations were milled using Katana UTML (Kuraray Noritake) in three groups with restoration thicknesses of 1, 2, and 3 mm, respectively. Each group had three subgroups using different cementation methods. For subgroup 1, restorations were cemented with self-adhesive cement. For subgroup 2, universal adhesive was applied and light cured. After the restoration was seated with conventional resin cement, light curing was performed. For subgroup 3, after adhesive was applied, the restoration was seated with conventional resin cement. Light curing was performed for the adhesive and cement simultaneously. After thermocycling, interfacial adaptation at the restoration-tooth interface was investigated using swept-source optical coherence tomography imaging. Finally, polymerization shrinkage of the cement was measured using a linometer and compared under the conditions of different zirconia thicknesses and light-curing durations. RESULTS: Interfacial adaptation varied signficantly depending on the zirconia thickness, pretreatment, polymerization mode and cements used (p < 0.05). The effects of the adhesive and polymerization shrinkage differed signficantly, depending on the reduced light under the zirconia (p < 0.05). CONCLUSION: Lower curing-light irradiance may lead to inferior adaptation and lower polymerization of the cement. Polymerization of resin cement can differ depending on the light irradiance and exposure duration.

Diagnostic Algorithm Based on Machine Learning to Predict Complicated Appendicitis in Children Using CT, Laboratory, and Clinical Features.

To establish a diagnostic algorithm for predicting complicated appendicitis in children based on CT and clinical features. METHODS: This retrospective study included 315 children (<18 years old) who were diagnosed with acute appendicitis and underwent appendectomy between January 2014 and December 2018. A decision tree algorithm was used to identify important features associated with the condition and to develop a diagnostic algorithm for predicting complicated appendicitis, including CT and clinical findings in the development cohort (n = 198). Complicated appendicitis was defined as gangrenous or perforated appendicitis. The diagnostic algorithm was validated using a temporal cohort (n = 117). The sensitivity, specificity, accuracy, and area under the receiver operating characteristic curve (AUC) from the receiver operating characteristic curve analysis were calculated to evaluate the diagnostic performance of the algorithm. RESULTS: All patients with periappendiceal abscesses, periappendiceal inflammatory masses, and free air on CT were diagnosed with complicated appendicitis. In addition, intraluminal air, transverse diameter of the appendix, and ascites were identified as important CT findings for predicting complicated appendicitis. C-reactive protein (CRP) level, white blood cell (WBC) count, erythrocyte sedimentation rate (ESR), and body temperature also showed important associations with complicated appendicitis. The AUC, sensitivity, and specificity of the diagnostic algorithm comprising features were 0.91 (95% CI, 0.86-0.95), 91.8% (84.5-96.4), and 90.0% (82.4-95.1) in the development cohort, and 0.7 (0.63-0.84), 85.9% (75.0-93.4), and 58.5% (44.1-71.9) in test cohort, respectively. CONCLUSION: We propose a diagnostic algorithm based on a decision tree model using CT and clinical findings. This algorithm can be used to differentiate between complicated and noncomplicated appendicitis and to provide an appropriate treatment plan for children with acute appendicitis.

Utilization of a Machine Learning Algorithm for the Application of Ancillary Features to LI-RADS Categories LR3 and LR4 on Gadoxetate Disodium-Enhanced MRI.

BACKGROUND: This study aimed to identify the important ancillary features (AFs) and determine the utilization of a machine-learning-based strategy for applying AFs for LI-RADS LR3/4 observations on gadoxetate disodium-enhanced MRI. METHODS: We retrospectively analyzed MRI features of LR3/4 determined with only major features. Uni- and multivariate analyses and random forest analysis were performed to identify AFs associated with HCC. A decision tree algorithm of applying AFs for LR3/4 was compared with other alternative strategies using McNemar's test. RESULTS: We evaluated 246 observations from 165 patients. In multivariate analysis, restricted diffusion and mild-moderate T2 hyperintensity showed independent associations with HCC (odds ratios: 12.4 [p < 0.001] and 2.5 [p = 0.02]). In random forest analysis, restricted diffusion is the most important feature for HCC. Our decision tree algorithm showed higher AUC, sensitivity, and accuracy (0.84, 92.0%, and 84.5%) than the criteria of usage of restricted diffusion (0.78, 64.5%, and 76.4%; all p < 0.05); however, our decision tree algorithm showed lower specificity than the criterion of usage of restricted diffusion (71.1% vs. 91.3%; p < 0.001). CONCLUSION: Our decision tree algorithm of applying AFs for LR3/4 shows significantly increased AUC, sensitivity, and accuracy but reduced specificity. These appear to be more appropriate in certain circumstances in which there is an emphasis on the early detection of HCC.

Urban seismic resilience mapping: a transportation network in Istanbul, Turkey.

When a seismic event occurs, transportation networks play a critical role in undertaking emergency activities such as evacuation and relief supply. Accordingly, to secure their functionality, it is essential to accurately assess their resilience. In particular, this study performs a rigorous probabilistic analysis on the seismic resilience of a transportation network in Istanbul, Turkey. The analysis accuracy is enhanced by considering, along with the structural damage of roadways, the additional disruption mode of network performance caused by the debris falling from damaged objects in their vicinity. Moreover, we obtain the results as a map of resilience measure, which enables us to investigate the disruption inequality across the study area and identify critical factors that govern the system resilience. To enable such sophisticated probabilistic analysis, a Bayesian network (BN) model is developed that involves various types of information from the hazard process to the performance of structures and systems. Then, the BN is quantified by identifying and compiling a comprehensive list of datasets. Thereby, this study analyses large-scale systems involving thousands of structures, while providing general probabilistic models and data schema that can be employed for other transportation networks.

Gastrointestinal stromal tumours: Preoperative imaging features to predict recurrence after curative resection.

PURPOSE: To identify whether preoperative factors could predict the recurrence after curative resection of gastrointestinal stromal tumours (GISTs) and evaluate the performance of a prediction model using preoperative factors for GIST recurrence compared to a model using preoperative/postoperative factors. METHOD: This retrospective study included patients who underwent curative resection and preoperative CT for GIST. CT imaging features as preoperative factors were analysed by two abdominal radiologists. Modified National Institutes of Health scores were accessed as a postoperative factor. Multiple logistic regression analysis was performed to assess the preoperative and postoperative factors in predicting GIST recurrence. Through the logistic regression, two prediction models using preoperative factors only and both preoperative/postoperative factors were constructed, respectively. The internal validation of the prediction models was performed using bootstrapping sampling. RESULTS: Data in 113 patients were evaluated. Among them, 14 patients had recurrence. The multiple logistic regression analysis demonstrated that non-gastric location (odds ratio [OR] = 5.12, p = 0.029), ill-defined margin (OR = 4.93, p = 0.023), and prominent vessels around tumour (OR = 6.78, p = 0.007) were significant factors. The prediction models using these preoperative factors and adding a postoperative factor showed an area under the receiver operating characteristic curve of 0.863 and 0.897, respectively, which were not statistically different. The bootstrapping sampling showed the two models were valid. CONCLUSION: The prediction model derived from non-gastric location, ill-defined margin, and prominent vessels around tumour can be used preoperatively to estimate the risk of recurrence after resection of GIST.

Prediction of insufficient hepatic enhancement during the Hepatobiliary phase of Gd-EOB DTPA-enhanced MRI using machine learning classifier and feature selection algorithms.

PURPOSE: The purpose of this study was to reveal the usefulness of machine learning classifier and feature selection algorithms for prediction of insufficient hepatic enhancement in the HBP. METHODS: We retrospectively assessed 214 patients with chronic liver disease or liver cirrhosis who underwent MRI enhanced with Gd-EOB-DTPA. Various liver function tests, Child-Pugh score (CPS) and Model for End-stage Liver Disease Sodium (MELD-Na) score were collected as candidate predictors for insufficient hepatic enhancement. Insufficient hepatic enhancement was assessed using liver-to-portal vein signal intensity ratio and 5-level visual grading. The clinico-laboratory findings were compared using Student's t-test and Mann-Whitney U test. Relationships between the laboratory tests and insufficient hepatic enhancement were assessed using Pearson's and Spearman's rank correlation coefficient. Feature importance was assessed by Random UnderSampling boosting algorithms. The predictive models were constructed using decision tree(DT), k-nearest neighbor(KNN), random forest(RF), and support-vector machine(SVM) classifier algorithms. The performances of the prediction models were analyzed by calculating the area under the receiver operating characteristic curve(AUC). RESULTS: Among four machine learning classifier algorithms using various feature combinations, SVM using total bilirubin(TB) and albumin(Alb) showed excellent predictive ability for insufficient hepatic enhancement(AUC = 0.93, [95% CI: 0.93-0.94]) and higher AUC value than conventional logistic regression(LR) model (AUC = 0.92, [95% CI; 0.92-0.93], predictive models using the MELD-Na (AUC = 0.90 [95% CI: 0.89-0.91]) and CPS (AUC = 0.89 [95% CI: 0.88-0.90]). CONCLUSION: Machine learning-based classifier (i.e. SVM) and feature selection algorithms can be used to predict insufficient hepatic enhancement in the HBP before performing MRI.

Prediction of transarterial chemoembolization refractoriness in patients with hepatocellular carcinoma using imaging features of gadoxetic acid-enhanced magnetic resonance imaging.

BACKGROUND: Repeated transarterial chemoembolization (TACE) can be associated with loss of its efficacy and subsequent tumor progression. PURPOSE: To identify features of gadoxetic acid-enhanced magnetic resonance imaging (MRI) associated with TACE refractoriness and to develop a prediction model for estimating the risk of TACE refractoriness. MATERIAL AND METHODS: Among 1025 patients with intermediate-stage hepatocellular carcinoma (HCC) who underwent TACE as a first-line treatment during 2010-2017, 427 patients who underwent preoperative gadoxetic acid-enhanced MRI were analyzed. According to the date of initial TACE, patients were divided into the development cohort (n = 211) and the test cohort (n = 216). TACE refractoriness was determined according to the Japan Society of Hepatology guidelines. Univariable and multivariable analyses were performed to investigate the association between clinical/MRI features and TACE refractoriness. The performance of the prediction model was internally and externally assessed using the C-index of discrimination and a Hosmer-Lemeshow goodness-of-fit test for calibration. RESULTS: By analyzing 427 patients, we constructed a prediction model with the following independent features associated with TACE refractoriness: maximum tumor size; tumor number; peritumoral hypointensity on hepatobiliary phase (HBP); and the presence of non-hypervascular hypointense nodule on HBP. This system enabled the prediction of TACE refractoriness in the development cohort (C-index, 0.796) and the test cohort (C-index, 0.738) with good discrimination and calibration abilities. CONCLUSION: The prediction model based on gadoxetic acid-enhanced MRI features in addition to the known predictors including tumor size and number can be used to estimate the risk of TACE refractoriness in patients with intermediate-stage HCC.

Right hydronephrosis as a sign of complicated appendicitis.

OBJECTIVE: Acute appendicitis is known for one of the most common cause of acute abdomen. However, it is still challenging to clearly distinguish complicated from uncomplicated appendicitis preoperatively. We investigated the association between right hydronephrosis and complicated appendicitis compared with other computed tomography (CT) findings of acute appendicitis. MATERIALS AND METHODS: 1275 patients who pathologically diagnosed with acute appendicitis were included. They were classified into the complicated appendicitis and uncomplicated appendicitis groups based on their histopathological results. We reviewed their CT findings, including right hydronephrosis, appendiceal wall defect, periappendiceal abscess, extraluminal or intraluminal free air, appendicolith, appendiceal dilatation, appendiceal wall thickening, periappendiceal infiltration, periappendiceal fluid collection, and ascites. Comparison between the two groups was performed and the diagnostic performance of each CT finding was evaluated. The location of appendix and periureteral extension of periappendiceal infiltration were evaluated in patients with right hydronephrosis. RESULTS: Out of 1275 patients, 29 (2.3 %) patients showed right hydronephrosis. Right hydronephrosis was significantly related to complicated appendicitis with the odds ratio of 4.90 (95 % confidence interval, 1.62-14.83; P = 0.005). Right hydronephrosis yielded specificity of 99.3 %. All patients with right hydronephrosis accompanied with periappendiceal infiltration and 28 (96.6 %) patients showed periureteral extension. Subcecal and pelvic areas are the most common locations, with 11 (37.9 %) patients each. CONCLUSION: The presence of right hydronephrosis was specific finding for complicated appendicitis and it could be considered as one of indirect sign of complicated appendicitis.

A pictorial review on clinicopathologic and radiologic features of duodenal gastrointestinal stromal tumors.

Duodenal gastrointestinal stromal tumors (GISTs) are rare, and studies on their management are not sufficient. Owing to the complex anatomy of the duodenum and pancreatic head, GISTs can be misdiagnosed as pancreatic head tumors. Surgical resection is the first treatment for localized duodenal GISTs; thus, noninvasive imaging is important for the diagnosis and treatment of GISTs. Computed tomography, magnetic resonance imaging and endoscopic ultrasonography findings can be helpful for the diagnosis of duodenal GISTs and can help differentiate GISTs from other adjacent tumors.

Comparison of the diagnostic performance of imaging criteria for HCCs ≤ 3.0 cm on gadoxetate disodium-enhanced MRI.

BACKGROUND AND PURPOSE: Imaging-based diagnostic systems play important roles in hepatocellular carcinoma (HCC). We aimed to compare the diagnostic performance of recently updated imaging criteria for HCCs ≤ 3.0 cm on gadoxetate disodium-enhanced magnetic resonance imaging (MRI). METHODS: 493 nodules (399 HCCs, 24 other malignancies, 70 benign) 1.0-3.0 cm from 400 patients, including 322 male (mean age 59.3 ± 9.4 years) and 78 female (mean age 61.2 ± 9.0 years), at risk for HCC who underwent gadoxetate disodium-enhanced MRI between July 2015 and December 2016 were retrospectively evaluated. Final diagnosis was determined histopathologically or clinically. The sensitivity and specificity in diagnosing HCC of the latest versions of four imaging criteria [Liver Imaging Reporting and Data System (LI-RADS), European Association for the Study of the Liver (EASL), Asian Pacific Association for the Study of the Liver (APASL), Korean Liver Cancer Association-National Cancer Center (KLCA-NCC)] were compared using generalized estimating equations. RESULTS: In 331 only pathologically diagnosed nodules, the sensitivities of both the APASL (86.8%) and KLCA-NCC criteria (85.4%) were significantly higher than the sensitivities of the EASL (71.8%) and LR-5 (71.1%) criteria (p < 0.001 for each pairwise comparison). However, the specificity of LR-5 was significantly higher than that of APASL (92.2% vs. 70.6%, respectively; p = 0.011) but did not differ significantly from the specificities of EASL (84.3%; p = 0.634) and KLCA-NCC (78.4%; p = 0.107). CONCLUSION: Of the four international imaging criteria, LI-RADS and EASL showed high specificity but suboptimal sensitivity for diagnosing HCCs ≤ 3 cm. However, APASL and KLCA-NCC had a higher sensitivity but a lower specificity than LI-RADS and EASL.

Development and Validation of a Simple Index Based on Non-Enhanced CT and Clinical Factors for Prediction of Non-Alcoholic Fatty Liver Disease.

OBJECTIVE: A widely applicable, non-invasive screening method for non-alcoholic fatty liver disease (NAFLD) is needed. We aimed to develop and validate an index combining computed tomography (CT) and routine clinical data for screening for NAFLD in a large cohort of adults with pathologically proven NAFLD. MATERIALS AND METHODS: This retrospective study included 2218 living liver donors who had undergone liver biopsy and CT within a span of 3 days. Donors were randomized 2:1 into development and test cohorts. CTL-S was measured by subtracting splenic attenuation from hepatic attenuation on non-enhanced CT. Multivariable logistic regression analysis of the development cohort was utilized to develop a clinical-CT index predicting pathologically proven NAFLD. The diagnostic performance was evaluated by analyzing the areas under the receiver operating characteristic curve (AUC). The cutoffs for the clinical-CT index were determined for 90% sensitivity and 90% specificity in the development cohort, and their diagnostic performance was evaluated in the test cohort. RESULTS: The clinical-CT index included CTL-S, body mass index, and aspartate transaminase and triglyceride concentrations. In the test cohort, the clinical-CT index (AUC, 0.81) outperformed CTL-S (0.74; p < 0.001) and clinical indices (0.73-0.75; p < 0.001) in diagnosing NAFLD. A cutoff of ≥ 46 had a sensitivity of 89% and a specificity of 41%, whereas a cutoff of ≥ 56.5 had a sensitivity of 57% and a specificity of 89%. CONCLUSION: The clinical-CT index is more accurate than CTL-S and clinical indices alone for the diagnosis of NAFLD and may be clinically useful in screening for NAFLD.

Direct Comparison of PI-RADS Version 2 and 2.1 in Transition Zone Lesions for Detection of Prostate Cancer: Preliminary Experience.

BACKGROUND: There appears to be less agreement in the identification of cancers in the transition zone (TZ), which is not as reliable as those in peripheral zone when using the Prostate Imaging Reporting and Data System (PI-RADS) version 2 (v2). In response to such shortcomings, the updated version 2.1 was introduced, which incorporated diffusion-weighted imaging (DWI) into category 2 and clarified lexicons. PURPOSE: To compare the diagnostic performance for the detection of clinically significant TZ prostate cancers (csPCa) and interreader agreement between PI-RADS v2.1 and v2. STUDY TYPE: Retrospective study. POPULATION: In all, 142 patients, 201 TZ lesions. FIELD STRENGTH/SEQUENCE: 3.0T; T2 -weighted image and DWI. ASSESSMENT: Lesions were scored by three independent readers using PI-RADS v2 and v2.1. STATISTICAL TESTS: The sensitivity and specificity at category ≥3 were compared between v2 and v2.1 using the generalized estimating equation model. Detection rates for csPCa of upgraded and downgraded lesions in the use of PI-RADS v2.1 from v2 were assessed. Interreader agreement was assessed using κ statistics. RESULTS: PI-RADS v2.1 showed a higher sensitivity and specificity (94.5% and 60.9%) than v2 (91.8% and 56.3%) for category ≥3 lesions in the detection of csPCa, although not significantly. Of eight upgraded lesions from category 2 to 3 (2 + 1) with an incorporated DWI, 50% (4/8) were csPCa. This was significantly higher than category 2 lesions (4.4%; P = 0.003). No csPCa was detected among the 22.8% (46/201) downgraded lesions. There was a moderate interreader agreement for scores ≥3 (κ = 0.565) in v2.1, which was slightly higher than that for v2 (κ = 0.534), although not significantly. DATA CONCLUSION: PI-RADS v2.1 provides moderate and comparable interreader agreement at category ≥3 than v2 in the TZ lesions. Upgraded lesions from category 2 to 3 demonstrated a higher detection rate of csPCa than category 2 lesions in v2.1. LEVEL OF EVIDENCE: 4 TECHNICAL EFFICACY STAGE: 2 J. Magn. Reson. Imaging 2020;52:577-586.

Extrauterine Adenomyoma of the Liver Mimicking a Hepatic Adenoma: A Case Report.

Extrauterine adenomyoma of the liver is extremely rare. Only a few cases have been reported, and these reports have focused mainly on histopathology. Herein, we report the specific imaging findings of extrauterine adenomyoma of the liver in a 43-year-old woman with epigastric pain, which was initially diagnosed as a hepatic adenoma. CT and MRI revealed a solid and cystic mass with hemorrhagic foci and weak persistent enhancement, located in the subcapsular region of the right hepatic lobe.

The role of multiphase CT in patients with acute postoperative bleeding after liver transplantation.

PURPOSE: The aim of this study was to investigate the role of multiphase computed tomography (CT) in patients with acute postoperative bleeding after liver transplantation(LT). METHODS: We retrospectively analyzed multiphase CT images in 270 post-LT bleeding patients between November 2013 and December 2017, with special attention to contrast extravasation (type I, focal or stipple; type II, jet). Patients were classified into conservative management trial and primary therapeutic intervention groups by initial treatment strategy, and then conservative management trial group was subdivided into successful conservative management and conservative management failure groups. On multiphase CT, we evaluated contrast extravasation volume, rate, and patterns (focal or stipple vs. jet). The concordances of the bleeding source determined by multiphase CT to the actual bleeding source were analyzed. RESULTS: Of 270 patients, 134 contrast extravasation sites were identified in 116 (43.0%) patients. Most (94.8%, 146/154) of patients without contrast extravasation was successfully managed by conservative management. The mean volume and rate of contrast extravasation significantly increased in order of successful conservative management, conservative management failure, and primary therapeutic intervention groups (all p < 0.01). In subgroup analysis, jet pattern contrast extravasation was more commonly observed with conservative management failure group (p = 0.01). In addition, the change in pattern of contrast extravasation from type I to II was significantly related to the conservative management failure (OR 10.3; 95% CI 1.8-60.4; p = 0.01). There was substantial agreement in localization of bleeding source between multiphase CT and surgery or angiography (Cohen Kappa = 0.78). CONCLUSION: Multiphase CT is helpful in the assessment for need of therapeutic intervention and to determine the treatment of choice in recipient with post-LT bleeding.

Feasibility of non-enhanced CT for assessing longitudinal changes in hepatic steatosis.

To evaluate the feasibility of computed tomography (CT) in the assessment of the change in hepatic steatosis (HS) in longitudinal follow-up by employing pathological HS as the reference standard.We retrospectively evaluated 38 living liver donor candidates (27 men and 11 women; mean age, 29.5 years) who underwent liver biopsy twice and had liver CT scans within 1 week of each biopsy. Four readers independently calculated CTL-S index by subtracting spleen attenuation from liver attenuation on non-enhanced CT images. The changes in pathological HS (ΔHS) and CTL-S (ΔCTL-S) between the 1st and 2nd examinations were assessed. The correlation between ΔHS and ΔCTL-S was assessed using the linear regression analysis. Inter-observer measurement error for ΔCTL-S among the 4 readers was assessed using the repeatability coefficient.ΔCTL-S showed a significant correlation with ΔHS in all readers (r = 0.571-0.65, P < .001). The inter-observer measurement error for ΔCTL-S was ±8.9. The ΔCTL-S values beyond the measurement error were associated with a consistent change in HS in 83.3% (13/15) to 100% (15/15), with sensitivities of 47.8 to 79.9% and specificities of 86.7 to 100% for detecting an absolute change of ≥10% in HS among the 4 readers. However, ΔCTL-S values within the measurement error were associated with a consistent change in HS in 43.5% (8/19) to 61.5% (16/26).The change in CTL-S roughly reflects the change in HS during longitudinal follow-up. A small change in CTL-S should not be considered meaningful, while a larger change in CTL-S beyond the measurement error strongly indicates a true change in HS.

Indirect Doppler ultrasound abnormalities of significant portal vein stenosis after liver transplantation.

PURPOSE: To determine indirect Doppler ultrasound (DUS) abnormalities associated with significant portal vein (PV) stenosis (PVS) in recipients of liver transplantation (LT). METHODS: This retrospective study was approved by our institutional review board. Between February 2006 and May 2017, 41 LT recipients were diagnosed with significant PVS, defined as having more than 50% narrowing of PV diameter for any reason, including thrombosis or flow disturbance associated with prominent collateral vessels on portal venography. We reviewed the DUS findings of hepatic arteries (HAs) as well as PVs of them, before and after treatment of PVS, and in comparison, with a one-to-one case-matched control. Inter-group comparison of frequency in DUS abnormalities was performed using Chi square (χ2) with Fisher's exact test and McNemar's test. Diagnostic values of each abnormal DUS finding and combinations were also evaluated. RESULTS: DUS of significant PVS showed "no demonstrable color flow," either at recipient PVs or anastomoses (26.7%), and showed turbulence (66.7%) and hepatofugal portal flow (HFPF; 20.0%) at the graft PVs. HFPF was more frequently observed in those with "no demonstrable color flow" at recipient PVs or anastomoses (p = 0.006). DUS of graft HAs revealed tardus-parvus waveforms (20.9%) and prolonged systolic acceleration times (16.3%), more commonly in the "no demonstrable color flow" group (p = 0.012). These indirect DUS abnormalities disappeared and resolved on follow-up DUS after treatment. In the control group, such Doppler abnormalities were less frequently shown than in the PVS group (p ≤ 0.01, respectively). When one of the portal-blood flow velocity (PFV)-related index abnormalities (such as increased time average velocity [TAV] at anastomosis and TAV ratio between recipient PV and anastomosis) or "no demonstrable color flow" were shown in DUS as well as one of the indirect DUS abnormalities, sensitivity, and specificity was 71.11 and 97.78%, respectively. CONCLUSION: In addition to PFV-related abnormalities, DUS occasionally shows "no demonstrable color flow" either at recipient PVs or anastomoses, and indirect Doppler abnormalities such as turbulence, HFPF at graft PVs, and abnormal waveforms at graft HAs in LT recipients with significant PVS. The combination of PFV-related abnormalities and indirect DUS abnormalities would be helpful for diagnosis of PVS.

CT indices for the diagnosis of hepatic steatosis using non-enhanced CT images: development and validation of diagnostic cut-off values in a large cohort with pathological reference standard.

OBJECTIVES: To compare the performances of CT indices for diagnosing hepatic steatosis (HS) and to determine and validate the CT index cut-off values. METHODS: Three indices were measured on non-enhanced CT images of 4413 living liver donor candidates (2939 men, 1474 women; mean age, 31.4 years): hepatic attenuation (CTL), hepatic attenuation minus splenic attenuation (CTL-S), and hepatic attenuation divided by splenic attenuation (CTL/S). The performances of these CT indices in diagnosing HS, relative to pathologic diagnosis, were compared in the development cohort of 3312 subjects by receiver operating characteristic (ROC) analysis. The cut-off values for diagnosing HS > 33% in the development cohort were determined at 95% specificity and 95% sensitivity using bootstrap ROC analysis, and the diagnostic performance of these cut-off values was validated in the test cohort of 1101 subjects. RESULTS: CTL-S showed the highest performance for diagnosing HS ≥ 5% and HS > 33% (areas under the curve (AUCs) = 0.737 and 0.926, respectively), followed by CTL/S (AUCs = 0.732 and 0.925, respectively) and CTL (AUCs = 0.707 and 0.880, respectively). For CT scans using 120 kVp, the CTL-S cut-off values for highly specific (i.e., - 2.1) and highly sensitive (i.e., 7.6) diagnosis of HS > 33% resulted in a specificity of 96.4% with a sensitivity of 64.0% and a sensitivity of 97.3% with a specificity of 54.9%, respectively, in the test cohort. CONCLUSION: CT indices using liver and spleen attenuations have higher performance for diagnosing HS than indices using liver attenuation alone. The CTL-S cut-off values in this study may have utility for diagnosing HS in clinical practice and research. KEY POINTS: • CT indices based on both liver attenuation and spleen attenuation (CTL-Sand CTL/S) have higher diagnostic performance than CTLbased on liver attenuation alone in diagnosing HS using various CT techniques. • The CT index cut-off values determined in this study can be utilized for reliable diagnosis or to rule out subjects with moderate to severe HS in clinical practice and research, including the selection of living liver donors and the development of cohorts with HS or healthy controls.

Visualization of Breast Microcalcifications on Digital Breast Tomosynthesis and 2-Dimensional Digital Mammography Using Specimens.

PURPOSE: The purpose of this study is to compare the visibility of microcalcifications of digital breast tomosynthesis (DBT) and full-field digital mammography (FFDM) using breast specimens. MATERIALS AND METHODS: Thirty-one specimens' DBT and FFDM were retrospectively reviewed by four readers. RESULTS: The image quality of microcalcifications of DBT was rated as superior or equivalent in 71.0% by reader 1, 67.8% by reader 2, 64.5% by reader 3, and 80.6% by reader 4. The Fleiss kappa statistic for agreement among readers was 0.31. CONCLUSIONS: We suggest that image quality of DBT appears to be comparable with or better than FFDM in terms of revealing microcalcifications.

2-Aryl substituted pyridine C-region analogues of 2-(3-fluoro-4-methylsulfonylaminophenyl)propanamides as highly potent TRPV1 antagonists.

A series of 2-aryl pyridine C-region derivatives of 2-(3-fluoro-4-methylsulfonylaminophenyl)propanamides were investigated as hTRPV1 antagonists. Multiple compounds showed highly potent TRPV1 antagonism toward capsaicin comparable to previous lead 7. Among them, compound 9 demonstrated anti-allodynia in a mouse neuropathic pain model and blocked capsaicin-induced hypothermia in a dose-dependent manner. Docking analysis of 9 with our hTRPV1 homology model provided insight into its specific binding mode.