Purpose To evaluate the image quality and diagnostic performance of SmartSpeed Precise diffusion-weighted imaging (DWI), a deep learning–based denoising and super-resolution reconstruction technique, compared with conventional DWI for the detection of hepatocellular carcinoma (HCC). Materials and Methods This retrospective analysis included 84 consecutive patients (mean age, 66.8 ± 9.1 years; 65 men) with liver cirrhosis who underwent gadoxetic acid–enhanced MRI including both conventional DWI (C-DWI) and SmartSpeed Precise DWI (P-DWI) between September 2025 and January 2026. A total of 137 HCC lesions were evaluated. Two radiologists independently assessed qualitative image quality and measured signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and apparent diffusion coefficient (ADC) values. Diagnostic performance for HCC detection was compared among three image sets: dynamic MRI alone, dynamic MRI plus C-DWI, and dynamic MRI plus P-DWI. Sensitivity was compared using McNemar testing, and receiver operating characteristic (ROC) analysis was performed to identify the optimal tumor size cut-off for detectability. A p value < 0.05 was considered statistically significant. Results Acquisition time was identical for C-DWI and P-DWI, as both were reconstructed from the same raw dataset. Qualitative image quality, SNR, and CNR did not differ significantly between techniques (all p > 0.05). However, ADC values were significantly lower with P-DWI than with C-DWI for both readers (Reader 1: 1.15 ± 0.25 vs 1.29 ± 0.25 × 10⁻ 3 mm²/s, p = 0.013; Reader 2: 1.21 ± 0.30 vs 1.32 ± 0.28 × 10⁻ 3 mm²/s, p = 0.036). Sensitivity for HCC detection was 65.7% (90/137) for dynamic MRI alone, 92.7% (127/137) for dynamic MRI plus C-DWI, and 98.5% (135/137) for dynamic MRI plus P-DWI. Both DWI-containing image sets showed significantly higher sensitivity than dynamic MRI alone (both p < 0.001). However, the difference between P-DWI and C-DWI was not statistically significant (p = 0.125). ROC analysis revealed that tumor size ≤ 1.4 cm was a significant predictor of missed lesions on C-DWI (AUC = 0.777, p < 0.001), where P-DWI demonstrated a numerical diagnostic advantage in detecting these small HCCs. Conclusion Deep learning–based SmartSpeed Precise DWI provided image quality and HCC detection performance comparable to those of conventional DWI without additional acquisition time. It showed lower ADC values with AI-based reconstruction, and there was no difference in HCC diagnostic performance between the two techniques. These findings suggest that SmartSpeed Precise DWI may serve as a feasible alternative to conventional DWI for liver diffusion imaging.

Leiomyosarcomas are malignant tumors derived from cells that exhibit smooth muscle differentiation. Although primary leiomyosarcoma of the stomach has occasionally been reported in the form of case reports, its publication in radiology journals is exceedingly rare; therefore, preoperative diagnosis remains challenging. Herein, we report the imaging and endoscopic findings of a 71-year-old woman with primary gastric leiomyosarcoma that was initially misdiagnosed as early gastric cancer on endoscopy and as a small subepithelial tumor on CT.

Background The CT/MRI Liver Imaging Reporting and Data System (LI-RADS) diagnostic algorithm classifies liver observations in patients with high-risk hepatocellular carcinoma (HCC) using imaging features. However, data regarding the diagnostic performance of specific LI-RADS major feature combinations is limited. Purpose To conduct a systematic review and individual participant data (IPD) meta-analysis to establish the positive predictive values (PPVs) of LI-RADS major feature combinations using CT/MRI LI-RADS version 2018 in patients at risk for HCC. Materials and Methods Medline, Embase, Cochrane Central, and Scopus were searched for studies published from January 2014 to February 2023. Studies reporting HCC percentages for LI-RADS categories in patients at high risk for HCC were included. A one-stage random-effects IPD meta-analysis was used to calculate the PPV for HCC diagnosis and 95% CIs of major feature combinations. Wald test was used to compare combinations. Risk of bias (RoB) was assessed using Quality Assessment of Diagnostic Accuracy Studies 2, known as QUADAS-2 (protocol: https://osf.io/ah5kn). Results Forty-six studies including 6765 patients (mean age, 59 years ± 10.69 [SD]; 75% male patients [5081 of 6765]; age range, 18-93 years) with 7500 liver observations were analyzed. High RoB in at least one domain was found in 80% of studies (37 of 46). The pooled PPV estimate for major feature combinations was 58.28% in LR-3 (95% CI: 44.00, 71.29), 80.82% in LR-4 (95% CI: 71.04, 87.86), and 95.81% in LR-5 (95% CI: 91.06, 98.09). The majority of LI-RADS major feature combinations had PPVs that did not differ from others within the same category, supporting the current categorization (P value ranges: LR-3, .17-.73; LR-4, .10 to >.99; LR-5, .08 to >.99). Notably, five major feature combinations differed from the pooled PPV of the LR category. LR-3 was lower without nonrim arterial phase hyperenhancement (APHE) measuring smaller than 20 mm without additional major features (14.81%; 95% CI: 6.35, 30.85; P < .001), and higher with APHE measuring 10-19 mm without additional major features (68.33%; 95% CI: 53.94, 79.90; P = .01). LR-4 was lower without APHE measuring 20 mm or larger with enhancing capsule (50.81%; 95% CI: 28.92, 72.39; P = .009). LR-5 was lower with APHE measuring 10-19 mm with threshold growth (74.40%; 95% CI: 51.06, 89.00; P < .001), and with APHE measuring 20 mm or larger with threshold growth (82.35%; 95% CI: 57.29, 94.20; P = .02). Conclusion This meta-analysis showed that most major feature combinations in the same CT/MRI LI-RADS category had similar PPVs for HCC in patients at high risk for HCC, with the exception of five combinations within LR-3 through LR-5. © RSNA, 2025 Supplemental material is available for this article. See also the editorial by Johnson in this issue.

Background A recent meta-analysis showed independent associations between most Liver Imaging Reporting and Data System (LI-RADS) ancillary features (AFs) and hepatocellular carcinoma (HCC), malignancy, and benignity. However, the impact of AFs on the diagnostic performance of LI-RADS remains unclear. Purpose To evaluate the impact of applying individual AFs on the diagnostic performance of CT and MRI LI-RADS using an individual participant data (IPD) meta-analysis. Materials and Methods Databases were searched for studies published from January 2014 to February 2023 that evaluated the diagnostic accuracy of CT and MRI for HCC in adults at risk for HCC using LI-RADS version 2014, 2017, or 2018. Observations were categorized according to LI-RADS major features, applying threshold growth when available, and excluding those previously treated or not meeting the composite reference standard (histopathologic analysis or imaging). Using a one-step approach, the IPD were pooled via bivariate mixed-effects models, accounting for clustering in participant-level and study-level random effects. The area under the receiver operator characteristic curve (AUC) for LI-RADS categories 1-5 and the positive predictive value (PPV), sensitivity, and specificity for LI-RADS category 5 (LR-5) observations were derived using three strategies: (a) major features only; (b) major features with each individual AF applied; and (c) similar to strategy 2 but allowing AFs favoring HCC in particular or malignancy in general to upgrade category LR-4 to category LR-5 when present. Comparisons were made using two-tailed z tests. Risk of bias was assessed using Quality Assessment of Diagnostic Accuracy Studies 2. Results Forty-six studies comprising 9257 observations (1098 CT, 8159 MRI) in 7811 adult participants (6792 male; mean age, 58.7 years ± 10.7 [SD]) were included. For all AFs, there were no differences in AUCs of LI-RADS categories 1-5 among strategies 1-3 (P value range, .65 to >.99). For category LR-5, there were also no differences among strategies 1-3 in the PPV, sensitivity, and specificity (P value range, .11 to >.99). Sensitivity analysis of only low-risk bias studies (nine of 46) yielded results consistent with primary analysis. Conclusion The application of individual AFs did not impact the overall diagnostic performance of CT and MRI LI-RADS compared with major features alone. © RSNA, 2025 Supplemental material is available for this article. See also the editorial by Searleman in this issue.

Background: Guidelines suggest the Liver Imaging Reporting and Data System (LI-RADS) may not be applicable for some populations at risk for hepatocellular carcinoma (HCC). However, data assessing the association of HCC risk factors with LI-RADS major features are lacking. Purpose: To evaluate whether the association between HCC risk factors and each CT/MRI LI-RADS major feature differs among individuals at-risk for HCC. Methods: Databases (MEDLINE, Embase, Cochrane Central Register of Controlled Trials, and Scopus) were searched from 2014 to 2022. Individual participant data (IPD) were extracted from studies evaluating HCC diagnosis using CT/MRI LI-RADS and reporting HCC risk factors. IPD from studies were pooled and modelled with one-stage meta-regressions. Interactions were assessed between major features and HCC risk factors, including age, sex, cirrhosis, chronic hepatitis B virus (HBV), and study location. A mixed effects model that included the major features, as well as separate models that included interactions between each risk factor and each major feature, were fit. Differences in interactions across levels of each risk factor were calculated using adjusted odds-ratios (ORs), 95% confidence-intervals (CI), and z-tests. Risk of bias was assessed using QUADAS-2. (Protocol: https://osf.io/tdv7j/ ). Results: Across 23 studies (2958 patients and 3553 observations), the associations between LI-RADS major features and HCC were consistent across several HCC risk factors ( P-value range: .09-.99). A sensitivity analysis among the 4 studies with a low risk of bias did not differ from the primary analysis. Conclusion: The association between CT/MRI LI-RADS major features and HCC risk factors do not significantly differ in individuals at-risk for HCC. These findings suggest that CT/MR LI-RADS should be applied to all patients considered at risk by LI-RADS without modification or exclusions, regardless of the presence or absence of the risk factors evaluated in this study.

Background: The independent contribution of each Liver Imaging Reporting and Data System (LI-RADS) CT or MRI ancillary feature (AF) has not been established. Purpose: To evaluate the association of LI-RADS AFs with hepatocellular carcinoma (HCC) and malignancy while adjusting for LI-RADS major features through an individual participant data (IPD) meta -analysis. Materials and Methods: Medline, Embase, Cochrane Central Register of Controlled Trials, and Scopus were searched from January 2014 to January 2022 for studies evaluating the diagnostic accuracy of CT and MRI for HCC using LI-RADS version 2014, 2017, or 2018. Using a one-step approach, IPD across studies were pooled. Adjusted odds ratios (ORs) and 95% CIs were derived from multivariable logistic regression models of each AF combined with major features except threshold growth (excluded because of infrequent reporting). Liver observation clustering was addressed at the study and participant levels through random intercepts. Risk of bias was assessed using a composite reference standard and Quality Assessment of Diagnostic Accuracy Studies 2. Results: Twenty studies comprising 3091 observations (2456 adult participants; mean age, 59 years +/- 11 [SD]; 1849 [75.3%] men) were included. In total, 89% (eight of nine) of AFs favoring malignancy were associated with malignancy and/or HCC, 80% (four of five) of AFs favoring HCC were associated with HCC, and 57% (four of seven) of AFs favoring benignity were negatively associated with HCC and/or malignancy. Nonenhancing capsule (OR = 3.50 [95% CI: 1.53, 8.01]) had the strongest association with HCC. Diffusion restriction (OR = 14.45 [95% CI: 9.82, 21.27]) and mild -moderate T2 hyperintensity (OR = 10.18 [95% CI: 7.17, 14.44]) had the strongest association with malignancy. The strongest negative associations with HCC were parallels blood pool enhancement (OR = 0.07 [95% CI: 0.01, 0.49]) and marked T2 hyperintensity (OR = 0.18 [95% CI: 0.07, 0.45]). Seventeen studies (85%) had a high risk of bias. Conclusion: Most LI-RADS AFs were independently associated with HCC, malignancy, or benignity as intended when adjusting for major features. (c) RSNA, 2024

The Liver Imaging Reporting and Data System (LI-RADS) does not consider factors extrinsic to the observation of interest, such as concurrent LR-5 observations. To evaluate whether the presence of a concurrent LR-5 observation is associated with a difference in the probability that LR-3 or LR-4 observations represent hepatocellular carcinoma (HCC) through an individual participant data (IPD) meta-analysis. Multiple databases were searched from 1/2014 to 2/2023 for studies evaluating the diagnostic accuracy of CT/MRI for HCC using LI-RADS v2014/2017/2018. The search strategy, study selection, and data collection process can be found at https://osf.io/rpg8x . Using a generalized linear mixed model (GLMM), IPD were pooled across studies and modeled simultaneously with a one-stage meta-analysis approach to estimate positive predictive value (PPV) of LR-3 and LR-4 observations without and with concurrent LR-5 for the diagnosis of HCC. Risk of bias was assessed using a composite reference standard and Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2). Twenty-nine studies comprising 2591 observations in 1456 patients (mean age 59 years, 1083 [74

Since 2007, the combination of atezolizumab and bevacizumab, comprising an immune checkpoint inhibitor and a molecularly targeted agent, has become the first-line treatment for advanced hepatocellular carcinoma (HCC). Predicting prognosis prior to systemic chemotherapy remains a critical concern. This study included 84 advanced HCC patients who underwent enhanced computed tomography (CT) and Gd-EOB-DTPA magnetic resonance imaging (MRI) before the systemic therapy were included. In CT, the 2 radiologists measured mean CT Hounsfield unit (CTHU) value by drawing region of interest at the largest diameter of the tumor on arterial phage. The HU values were categorized into 5 groups: ≤ 0, 0 < HU ≤ 50, 50 < HU ≤ 100, 100 < HU ≤ 150, and HU > 150. The percentage of the entire tumor in each category was calculated. On MRI, hepatobiliary phase imaging features and relative enhancement ratio (RER) were also evaluated by 2 radiologists. Prognostic factors associated with progression-free survival were identified using statistical analysis. RER on HBP MRI correlated with prognosis in systemic chemotherapy. Conversely, other image features on HBP MRI and CT histogram provided consistent treatment effect.

Purpose The purpose of this study was to determine the feasibility of early Superb microvascular imaging (SMI) for prediction of the effect of HCC treatment after transcatheter arterial chemoembolization (TACE).Materials and Methods A total of 96 HCCs (70 patients) treated with TACE between September 2021 and May 2022 were included in this study. SMI, Color Doppler imaging (CDI), and Power Doppler imaging (PDI) were performed the day after TACE for evaluation of intratumoral vascularity of the lesion using an Aplio500 ultrasound scanner (Toshiba Medical Systems, Corporation, Tochigi, Japan). Grading of the vascular presence was performed using a five-point scale. A dynamic CT image taken after 29-42 days was used for comparison of sensitivity, specificity, and accuracy for detection of tumor vascularity between SMI, CDI, and PDI. Univariate and multivariate analysis were performed for assessment of factors affecting intratumoral vascularity.Results Fifty-eight lesions (60%) showed complete remission (CR) and 38 lesions (40%) showed partial response (PR) or no response at 29-42 days on Multi-detector Computed Tomography (MDCT) after TACE. SMI showed sensitivity of 86.84% for detection of intratumoral flow, which was significantly higher compared with that of CDI (10.53%, p < 0.001) and PDI (36.84%, p < 0.001). The results of multivariate analysis indicated that tumor size was a significant factor in detection of blood flow using the SMI technique.Conclusion Early SMI may be utilized as an adjunctive diagnostic test for evaluation of treated lesions after TACE, particularly when the location of the tumor is in an area of the liver where a suitable sonic window can be identified.

Ciliated foregut cyst is a relatively rare disease; thus, most reports are in the form of case studies. This benign cyst is usually found in the mediastinum and account for approximately 20% of all mediastinal masses. However, it is rarely found in the hepatobiliary and peripancreatic regions. Approximately 20 cases of ciliated foregut cysts involving the pancreas have been reported in the Enlgish literature. Here, we present a case of ciliated foregut cyst that occurred in the tail of the pancreas in a 29-yearold female. The patient’s ultrasonography, CT, and MRI findings are presented, along with a review of the literature.

Background A simplification of the Liver Imaging Reporting and Data System (LI-RADS) version 2018 (v2018), revised LI-RADS (rLI-RADS), has been proposed for imaging-based diagnosis of hepatocellular carcinoma (HCC). Single-site data suggest that rLI-RADS category 5 (rLR-5) improves sensitivity while maintaining positive predictive value (PPV) of the LI-RADS v2018 category 5 (LR-5), which indicates definite HCC. Purpose To compare the diagnostic performance of LI-RADS v2018 and rLI-RADS in a multicenter data set of patients at risk for HCC by performing an individual patient data meta-analysis. Materials and Methods Multiple databases were searched for studies published from January 2014 to January 2022 that evaluated the diagnostic performance of any version of LI-RADS at CT or MRI for diagnosing HCC. An individual patient data meta-analysis method was applied to observations from the identified studies. Quality Assessment of Diagnostic Accuracy Studies version 2 was applied to determine study risk of bias. Observations were categorized according to major features and either LI-RADS v2018 or rLI-RADS assignments. Diagnostic accuracies of category 5 for each system were calculated using generalized linear mixed models and compared using the likelihood ratio test for sensitivity and the Wald test for PPV. Results Twenty-four studies, including 3840 patients and 4727 observations, were analyzed. The median observation size was 19 mm (IQR, 11-30 mm). rLR-5 showed higher sensitivity compared with LR-5 (70.6% [95% CI: 60.7, 78.9] vs 61.3% [95% CI: 45.9, 74.7]; P < .001), with similar PPV (90.7% vs 92.3%; P = .55). In studies with low risk of bias (n = 4; 1031 observations), rLR-5 also achieved a higher sensitivity than LR-5 (72.3% [95% CI: 63.9, 80.1] vs 66.9% [95% CI: 58.2, 74.5]; P = .02), with similar PPV (83.1% vs 88.7%; P = .47). Conclusion rLR-5 achieved a higher sensitivity for identifying HCC than LR-5 while maintaining a comparable PPV at 90% or more, matching the results presented in the original rLI-RADS study. © RSNA, 2023 Supplemental material is available for this article. See also the editorial by Sirlin and Chernyak in this issue.

BACKGROUND:LI-RADS version 2018 (v2018) is used for non-invasive diagnosis of hepatocellular carcinoma (HCC). A recently proposed modification (known as mLI-RADS) demonstrated improved sensitivity while maintaining specificity and positive predictive value (PPV) of LI-RADS category 5 (definite HCC) for HCC. However, mLI-RADS requires multicenter validation. PURPOSE:To evaluate the performance of v2018 and mLI-RADS for liver lesions in a large, heterogeneous, multi-national cohort of patients at risk for HCC. STUDY TYPE:Systematic review and meta-analysis using individual participant data (IPD) [Study Protocol: https://osf.io/duys4]. POPULATION:2223 observations from 1817 patients (includes all LI-RADS categories; females = 448, males = 1361, not reported = 8) at elevated risk for developing HCC (based on LI-RADS population criteria) from 12 retrospective studies. FIELD STRENGTH/SEQUENCE:1.5T and 3T; complete liver MRI with gadoxetate disodium, including axial T2w images and dynamic axial fat-suppressed T1w images precontrast and in the arterial, portal venous, transitional, and hepatobiliary phases. Diffusion-weighted imaging was used when available. ASSESSMENT:Liver observations were categorized using v2018 and mLI-RADS. The diagnostic performance of each system's category 5 (LR-5 and mLR-5) for HCC were compared. STATISTICAL TESTS:The Quality Assessment of Diagnostic Accuracy Studies version 2 (QUADAS-2 was applied to determine risk of bias and applicability. Diagnostic performances were assessed using the likelihood ratio test for sensitivity and specificity and the Wald test for PPV. The significance level was P < 0.05. RESULTS:17% (2/12) of the studies were considered low risk of bias (244 liver observations; 164 patients). When compared to v2018, mLR-5 demonstrated higher sensitivity (61.3% vs. 46.5%, P < 0.001), similar PPV (85.3% vs. 86.3%, P = 0.89), and similar specificity (85.8% vs. 90.8%, P = 0.16) for HCC. DATA CONCLUSION:This study confirms mLR-5 has higher sensitivity than LR-5 for HCC identification, while maintaining similar PPV and specificity, validating the mLI-RADS proposal in a heterogeneous, international cohort. LEVEL OF EVIDENCE:3 TECHNICAL EFFICACY: Stage 2.

Background The Liver Imaging Reporting and Data System (LI-RADS) assigns a risk category for hepatocellular carcinoma (HCC) to imaging observations. Establishing the contributions of major features can inform the diagnostic algorithm. Purpose To perform a systematic review and individual patient data meta-analysis to establish the probability of HCC for each LI-RADS major feature using CT/MRI and contrast-enhanced US (CEUS) LI-RADS in patients at high risk for HCC. Materials and Methods Multiple databases (MEDLINE, Embase, Cochrane Central Register of Controlled Trials, and Scopus) were searched for studies from January 2014 to September 2019 that evaluated the accuracy of CT, MRI, and CEUS for HCC detection using LI-RADS (CT/MRI LI-RADS, versions 2014, 2017, and 2018; CEUS LI-RADS, versions 2016 and 2017). Data were centralized. Clustering was addressed at the study and patient levels using mixed models. Adjusted odds ratios (ORs) with 95% CIs were determined for each major feature using multivariable stepwise logistic regression. Risk of bias was assessed using Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2) (PROSPERO protocol: CRD42020164486). Results A total of 32 studies were included, with 1170 CT observations, 3341 MRI observations, and 853 CEUS observations. At multivariable analysis of CT/MRI LI-RADS, all major features were associated with HCC, except threshold growth (OR, 1.6; 95% CI: 0.7, 3.6; P = .07). Nonperipheral washout (OR, 13.2; 95% CI: 9.0, 19.2; P = .01) and nonrim arterial phase hyperenhancement (APHE) (OR, 10.3; 95% CI: 6.7, 15.6; P = .01) had stronger associations with HCC than enhancing capsule (OR, 2.4; 95% CI: 1.7, 3.5; P = .03). On CEUS images, APHE (OR, 7.3; 95% CI: 4.6, 11.5; P = .01), late and mild washout (OR, 4.1; 95% CI: 2.6, 6.6; P = .01), and size of at least 20 mm (OR, 1.6; 95% CI: 1.04, 2.5; P = .04) were associated with HCC. Twenty-five studies (78%) had high risk of bias due to reporting ambiguity or study design flaws. Conclusion Most Liver Imaging Reporting and Data System major features had different independent associations with hepatocellular carcinoma; for CT/MRI, arterial phase hyperenhancement and washout had the strongest associations, whereas threshold growth had no association. © RSNA, 2021 Online supplemental material is available for this article.

There is a wide spectrum of congenital anomalies or variations of the aortic arch, ranging from non-symptomatic variations that are mostly detected incidentally to clinically symptomatic variations that cause severe respiratory distress or esophageal compression. Some of these may be accompanied by other congenital heart diseases or chromosomal anomalies. The widespread use of multidetector computed tomography (CT) in clinical practice has resulted in incidental detection of several variations of the aortic arch in adults. Thus, radiologists and clinicians should be aware of the classification of aortic arch anomalies and carefully look for imaging features associated with a high risk of clinical symptoms. Understanding the embryological development of the aortic arch aids in the classification of various subtypes of aortic arch anomalies and variants. For accurate diagnosis and precise evaluation of aortic arch anomalies, cross-sectional imaging modalities, such as multidetector CT or magnetic resonance imaging, play an important role by providing three-dimensional reconstructed images. In this review, we describe the embryological development of the thoracic aorta and discuss variations and anomalies of the aortic arch along with their clinical implications.

Objective: To evaluate the diagnostic performance of Liver Imaging Reporting and Data System (LI-RADS) version 2018 ancillary features for the diagnosis of hepatocellular carcinoma (HCC) from LR-4 ('probably HCC') lesions using gadoxetic acid-enhanced magnetic resonance imaging.Methods: This retrospective study evaluated 166 LR-4 lesions including ancillary features in 114 high-risk cases imaged with gadoxetic acid-enhanced magnetic resonance imaging between March 2015 and December 2017.Two radiologists evaluated the imaging features using LI-RADS v2018.All lesions were confirmed as HCC or benign lesions by pathological assessment or >2 years of follow-up imaging.The diagnostic contribution of ancillary features was assessed using simple and multivariable logistic regression and generalised estimating equations.Results: In all, 114 HCCs (68.7%) and 52 benign lesions (31.3%) were confirmed.Simple logistic regression analysis revealed that mild to moderate T2 hyperintensity (p = 0.014), restricted diffusion (p < 0.001), and intralesional fat (p = 0.018) were statistically significant for differentiating HCCs from benign lesions; however, multivariable logistic analysis revealed that only restricted diffusion was statistically significant (adjusted odds ratio = 9.703, p < 0.001).Restricted diffusion had lower sensitivity (48.2%) and higher specificity (90.4%) for the diagnosis of HCC; however, the diagnostic values improved when combined with mild to moderate T2 hyperintensity and hepatobiliary phase hypointensity (sensitivity: 73.8%, specificity: 80.8%).Conclusion: Among ancillary LI-RADS v2018 imaging features, restricted diffusion is the diagnostic feature most accurately distinguishing HCCs from benign abnormalities in LR-4 lesions.

OBJECTIVE:To characterize the use of portal venous or delayed phase CT as an alternative to estimate washout for the non-invasive diagnosis of hepatocellular carcinoma (HCC) on gadoxetic acid-enhanced MRI in combination with other features.METHODS:This retrospective study included 226 observations (n = 162 patients) at high risk for HCC imaged with gadoxetic acid-enhanced MRI and enhanced liver CT between March 2015 and March 2018. Two radiologists independently evaluated two sets of images and assigned the final Liver Imaging Reporting and Data System (LI-RADS) categories by consensus using gadoxetic acid-enhanced MRI. LR-1, LR-2, LR-5, and LR-M were excluded from the study.The observations were divided using different criteria for washout: hypointensity on the portal venous phase (PVP) at MRI (criteria 1), hypointensity on PVP at MRI and/or hypoattenuation on the PVP/delayed phase at dynamic CT (criteria 2), and hypointensity on the PVP and/or hepatobiliary phase at MRI (criteria 3). The sensitivity, specificity, and accuracy for the diagnosis of HCC were analyzed for each criterion.RESULTS:Using gadoxetic acid-enhanced, 226 lesions were diagnosed as LR-3 or LR-4 by LI-RADS. Among them, 98 and 152 had "washout" at criteria 1 and 2, respectively. For the diagnosis of HCC, criteria 2 and 3 showed significantly higher sensitivities (67.3 and 92.5%, respectively) compared with criteria 1 (35.5%) (p < 0.001). The specificity of criteria 3 (13%) was significantly lower than those of criteria 1 and 2 (40.7% and 38.4%, respectively, p < 0.001). The specificities between criteria 1 and 2 were not statistically different (p = 0.427).CONCLUSION:Although the LI-RADS lexicon does not permit the interchange of image features among various image modalities, the sensitivity of HCC diagnosis could be improved without any decrease in specificity by adding CT image washout features.ADVANCES IN KNOWLEDGE:Although the LI-RADS lexicon does not permit the interchange of image features among various image modalities, complementary use of dynamic CT in LR-3 or LR-4 categories on the basis of gadoxetic acid-enhanced MRI may contribute to major imaging feature.

OBJECTIVES:According to LI-RADS, a major discriminating feature between hepatocellular carcinoma (HCC) and non-HCC malignancies is the subtype of arterial phase hyperenhancement (APHE). The aim of this study was to investigate whether APHE subtypes are consistent across multi-arterial phase (mHAP) MRI acquisitions while evaluating reader agreement. Secondarily, we investigated factors that may affect reader agreement for APHE subtype.METHODS:In this retrospective study, consecutive patients with liver cirrhosis and focal observations who underwent mHAP were included. Five radiologists reviewed MR images in 2 reading sessions. In reading session 1, individual AP series were reviewed and scored for presence of APHE and subtype. In reading session 2, readers scored observations' major and ancillary features and LI-RADS category in the complete MRI examination. Reader agreement was calculated using Fleiss' kappa for binary outcomes and Kendall's coefficient of concordance for LI-RADS categories. Univariate mixed effects logistic regressions were performed to investigate factors affecting agreement.RESULTS:In total, 61 patients with 77 focal observations were analyzed. Of observations unanimously scored as having APHE, 27.7% showed both rim and nonrim subtypes on mHAP. Inter-reader agreement for APHE subtype ranged from 0.49 (95% CI: 0.33, 0.64) to 0.57 (95% CI: 0.40, 0.74) between reading sessions. Observation size had a trend level effect on rim APHE agreement (p = 0.052).CONCLUSION:Approximately 1/3 of observations demonstrated inconsistent APHE subtype during mHAP acquisition. Small lesions were particularly challenging. Further guidance on APHE subtype classification, especially when applied to mHAP, could be a focus of LI-RADS refinement.KEY POINTS:• In a cohort of patients at risk for HCC, 28% of the observations showed inconsistent arterial phase hyperenhancement (APHE) subtypes (rim and nonrim) on multi-arterial phase imaging according to the majority score of 5 independent readers. • Inconsistent APHE subtypes may challenge reliable imaging diagnosis, i.e., LI-RADS categorization, of focal liver observations in patients at risk for HCC.

Abstract Background Electrical cardioversion (ECV) is an effective method for restoring sinus rhythm after atrial fibrillation (AF). However, early recurrence of AF occurs in a significant number of patients after ECV. This study aimed to identify electrocardiographic (ECG) predictors of early AF recurrence after ECV. Methods A total of 272 patients with persistent AF undergoing successful ECV were consecutively enrolled in this study. We investigated clinical, echocardiographic, and ECG data. The 12‐lead ECG parameters were measured during sinus rhythm right after ECV using a digital caliper. The early AF recurrence was defined as recurrence within 2 months. Results Of the 272 patients, 165 patients (60.7%) experienced an early AF recurrence. Maximum P‐wave duration (PWD) in limb leads (OR: 1.086; 95% CI: 1.019–1.157; p = .012) and P‐terminal force (PTF) in V1 (OR: 1.019; 95% CI: 1.004–1.033; p = .011) were independent predictors of early AF recurrence after ECV. The optimal cutoff value of the maximum PWD in limb leads for predicting early AF recurrence was 134 ms, characterized by 90.3% sensitivity and 72.0% specificity. Likewise, the optimal cutoff value of PTF in V1 was 50 ms × mm, characterized by 80.0% sensitivity and 64.5% specificity. Conclusion A longer PWD (>134 ms) and a larger PTF (>50 ms × mm) were useful predictors of early recurrence of AF after successful ECV in clinical practice. A more effective rhythm control therapy such as catheter ablation or rate control strategy rather than a repeat ECV should be considered.

BACKGROUND:The efficacy of catheter ablation for persistent atrial fibrillation (AF) remains suboptimal. A hybrid approach of catheter ablation combined with totally thoracoscopic surgical ablation can improve outcomes. In this study, we evaluated the efficacy of the early staged hybrid procedure in hospital stay after totally thoracoscopic ablation compared to the stand-alone totally thoracoscopic ablation.METHODS:Patients who underwent totally thoracoscopic ablation from February 2012 to December 2018 were included in this study. We compared the outcomes of the totally thoracoscopic ablation only group versus the early staged hybrid procedure group. The primary outcome was recurrence of atrial tachyarrhythmia after three months of blanking period. The secondary outcome was repeated unplanned additional electrophysiology study and catheter ablation due to atrial tachyarrhythmia recurrence.RESULTS:A total of 306 patients (mean age, 56.8 ± 8.5 years; 278 [90.8%] males) was included in the study, with 81 patients in the early staged hybrid group and 225 patients in the stand-alone totally thoracoscopic ablation only group. The mean follow-up duration was 30.0 months. Overall arrhythmia-free survival showed no significant difference between the two groups (log-rank P = 0.402). There was no significant difference in the rate of repeat procedure between the two groups (log-rank = 0.11).CONCLUSION:The early staged hybrid procedure after thoracoscopic ablation could not improve the outcome of recurrence of atrial tachyarrhythmia. The second stage of electrophysiology study could be deferred to patients with recurrence of atrial tachyarrhythmia during follow up after totally thoracoscopic ablation.

BACKGROUND:In idiopathic outflow tract ventricular arrhythmias (OT-VAs), identifying the site with the earliest activation time (EAT) using activation mapping is critical to eliminating the arrhythmogenic focus. However, the optimal EAT for predicting successful radiofrequency catheter ablation (RFCA) has not been established.HYPOTHESIS:To evaluate the association between EAT and successful RFCA in idiopathic OT-VAs and to determine the optimal cut-off value of EAT for successful ablation.METHODS:We retrospectively analyzed patients undergoing RFCA for idiopathic OT-VAs at a single center from January 2015 to December 2019.RESULTS:Acute procedural success was achieved in 168 patients (87.0%). Among these patients, 158 patients (81.9%) were classified in the clinical success group according to the recurrence of clinical VAs during median (Q1, Q3) follow-up (330 days [182, 808]). EAT was significantly earlier in the clinical success group compared with the recurrence (p = .006) and initial failure (p < .0001) groups. The optimal EAT cut-off value predicting clinical success was -30 ms in the right ventricular outflow tract (RVOT) with 77.4% sensitivity and 96.4% specificity. In all cases of successful ablation in the left ventricular outflow tract (LVOT), EAT in the RVOT was not earlier than -29 ms.CONCLUSIONS:EAT in patients with successful catheter ablation was significantly earlier than that in patients with recurrence and initial failure. EAT earlier than -30 ms could be used as a key predictor of successful catheter ablation as well as an indicator of the need to shift focus from the RVOT to the LVOT.