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We tried to evaluate the added value of positive intraluminal contrast CT over fluoroscopy to detect anastomotic leakage after gastrointestinal surgery. 141 GI surgery patients with both fluoroscopic examinations and CT were included. Two radiologists reviewed fluoroscopic images with/without CT for determining anastomotic leakage on 5-point confidence scale and grading the leakage on 4-point grading system. Duration of hospital stay and type of treatment were recorded. Radiologists’ diagnostic performances for determining leakage were compared using the ROC analysis and inter-observer agreement was analyzed. 53 patients had GI leakage. When CT were added to fluoroscopic images, the AUC values significantly increased for both reviewers (from 0.859 to 0.942 for reviewer 1, P = 0.001; from 0.757 to 0.879 for reviewer 2, P = 0.002). Interobserver agreement between the two reviewers for the presence of leakage was excellent and improved with the addition of CT (weighted-kappa value, 0.869 versus 0.805). Postoperative intervention was more frequently performed (P

Background Quantitative US (QUS) using radiofrequency data analysis has been recently introduced for noninvasive evaluation of hepatic steatosis. Deep learning algorithms may improve the diagnostic performance of QUS for hepatic steatosis. Purpose To evaluate a two-dimensional (2D) convolutional neural network (CNN) algorithm using QUS parametric maps and B-mode images for diagnosis of hepatic steatosis, with the MRI-derived proton density fat fraction (PDFF) as the reference standard, in patients with nonalcoholic fatty liver disease (NAFLD). Materials and Methods: Consecutive adult participants with suspected NAFLD were prospectively enrolled at a single academic medical center from July 2020 to June 2021. Using radiofrequency data analysis, two QUS parameters (tissue attenuation imaging [TAI] and tissue scatter-distribution imaging [TSI]) were measured. On B-mode images, hepatic steatosis was graded using visual scoring (none, mild, moderate, or severe). Using B-mode images and two QUS parametric maps (TAI and TSI) as input data, the algorithm estimated the US fat fraction (USFF) as a percentage. The correlation between the USFF and MRI PDFF was evaluated using the Pearson correlation coefficient. The diagnostic performance of the USFF for hepatic steatosis (MRI PDFF ≥5%) was evaluated using receiver operating characteristic curve analysis and compared with that of TAI, TSI, and visual scoring. Results Overall, 173 participants (mean age, 51 years ± 14 [SD]; 96 men) were included, with 126 (73%) having hepatic steatosis (MRI PDFF ≥5%). USFF correlated strongly with MRI PDFF (Pearson r = 0.86, 95% CI: 0.82, 0.90

Background Diagnostic performance of the Liver Imaging Reporting and Data System tumor in vein (LR-TIV) category at CT and/or MRI has not yet been evaluated, to the knowledge of the authors. Purpose To assess the diagnostic performance of the LR-TIV category in detecting macroscopic tumors in veins (TIVs) at CT and hepatobiliary contrast agent-enhanced (HBA) MRI, with pathologic results used as the reference standard. Materials and Methods Between January 2010 and December 2019, consecutive patients with or without macroscopic TIV who underwent both CT and HBA MRI before hepatic resection or liver transplant were retrospectively included. Three radiologists independently assessed the LR-TIV features of enhancing soft tissue in vein and features suggestive of TIV (FSTIV) and reached a consensus. Macroscopic TIV at pathologic examination was the reference standard. Sensitivities and specificities of the LR-TIV category without and with FSTIV were calculated, and the added value of FSTIV was evaluated by using the McNemar test. Results In the 1322 patients with (n = 101) or without (n = 1221) macroscopic TIV (median age, 64 years [interquartile range, 58-70 years]; 1053 men), without consideration of FSTIV, the sensitivity and specificity of enhancing soft tissue in vein for detecting macroscopic TIV at pathologic examination were 64.4% (65 of 101) and 99.8% (1218 of 1221) with CT and 62.4% (63 of 101) and 99.8% (1218 of 1221) with HBA MRI, respectively. With consideration of FSTIV, the sensitivity and specificity of the LR-TIV category became 67.3% (68 of 101 patients) and 99.7% (1217 of 1221 patients) at both CT and HBA MRI. No difference was found between measurements without and with FSTIV (sensitivity, 62% vs 67% for CT [P = .45] and 64% vs 67% for HBA MRI [P = .18]; specificity, 99% for both CT and HBA MRI [P > .99 for both]). Conclusion The Liver Imaging Reporting and Data System tumor in vein category showed moderate sensitivity and high specificity in the detection of macroscopic tumors in veins at both CT and hepatobiliary contrast agent-enhanced MRI, with pathologic examination used as the reference standard. © RSNA, 2021 Online supplemental material is available for this article. See also the editorial by Morrell in this issue.

To identify features on preoperative MR imaging with diffusion-weighted imaging (DWI) for predicting next-generation sequencing (NGS)-based tumor cellularity and patient outcome after surgical resection of pancreatic ductal adenocarcinoma (PDAC). This retrospective study included 105 patients with surgically resected PDAC who underwent preoperative MR imaging with DWI. Tumor cellularity was measured using molecular techniques and bioinformatics methods. Clinico-pathologic findings including tumor T stage for predicting disease-free survival (DFS) and overall survival (OS) were identified using Cox proportional hazards model. Important MR imaging findings including apparent diffusion coefficient (ADC) value of PDAC and modified ADC value (the ratio of the ADC value of PDAC to the ADC value of the spleen) for predicting higher tumor cellularity (≥ 30%) and poor prognosis were also identified. The median DFS and OS were 12.0 months [95% confidence interval (CI), 8.0–17.0] and 22.0 months (95% CI, 18.0–29.0), respectively. Higher T stage (T3/4) [hazard ratio (HR), 7.720, (95% CI 1.072, 55.612); p = 0.048] and higher tumor cellularity [HR, 1.599 (95% CI, 1.003–2.548); p = 0.048] were significantly associated with worse DFS. Among MR imaging features, the modified ADC value was significantly associated with tumor cellularity [odds ratio, 0.068 (95% CI, 0.012–0.372); p = 0.002], and PDAC with lower modified ADC value [≤ 1.40 (cutoff value)] showed significantly shorter median DFS than PDAC with higher modified ADC value [8 months (95% CI, 4–12) vs. 16 months (95% CI, 10–29); HR, 1.713 (95% CI, 1.073–2.735), log-rank p = 0.024]. Higher NGS-based tumor cellularity may be a negative prognostic factor in pancreatic cancer after resection, and modified ADC value derived from DWI could be helpful in predicting tumor cellularity and patient surgical outcome with regard to recurrence.

To determine the appropriate use of ancillary features (AFs) in upgrading LI-RADS category 3 (LR-3) to category 4 (LR-4) for hepatic nodules on gadoxetic acid–enhanced MRI. We retrospectively analyzed MRI features of solid hepatic nodules (≤ 30 mm) categorized as LR-3/4 on gadoxetic acid–enhanced MRI. In LI-RADS diagnostic table-based-LR-3 observations, logistic regression analyses were performed to identify AFs suggestive of hepatocellular carcinomas (HCCs) rather than non-malignant nodules. Using McNemar’s test, the sensitivities and specificities of the final-LR-4 category for HCC diagnosis were compared according to the principles of AF application in category adjustment. A total of 336 hepatic nodules (191 HCCs; 145 non-malignant) in 252 patients were evaluated. Based on major HCC features, 248 nodules (123 HCCs) were assigned as table-based-LR-3 and 88 nodules (68 HCCs) as table-based-LR-4. In table-based-LR-3 observations, mild–moderate T2 hyperintensity was identified as an independent predictor of HCC as opposed to non-malignant nodules (odds ratio = 3.01, p = 0.002). For HCC diagnosis, different criteria of final-LR-4: only table-based-LR-4, allowing category upgrade using only T2 hyperintensity, or using any AFs favoring malignancy resulted in sensitivities of 35.6% (68/191), 53.9% (103/191), and 88.5% (169/191), and specificities of 86.2% (125/145), 75.9% (110/145), and 21.4% (31/145), respectively, which differed from each other (all p < 0.001). While the application of MRI AF in LI-RADS category adjustment increases the sensitivity of LR-4 category for HCC diagnosis, it is accompanied by a significant decrease in specificity. Mild–moderate T2 hyperintensity, a significant AF indicative of HCC, may be more appropriate for upgrading LR-3 to LR-4. • When upgrading from LR-3 to LR-4 using any MRI ancillary features favoring malignancy, LR-4 sensitivity increases but specificity decreased for HCC diagnosis. • By upgrading LR-3 to LR-4 based on MRI ancillary features found to suggest HCC rather than non-malignant nodules in multivariate analysis (i.e., mild–moderate T2 hyperintensity), LR-4 demonstrated a more balanced sensitivity and specificity for HCC diagnosis (53.9% and 75.9%, respectively).

Background The Liver Imaging Reporting and Data System (LI-RADS), version 2018, treatment response algorithm (TRA) is used to assess hepatocellular carcinoma (HCC) after local-regional therapy (LRT). However, its diagnostic performance has not yet been fully compared between CT and hepatobiliary agent (HBA)-enhanced MRI in patients who have undergone liver transplant (LT). Purpose To compare the diagnostic performance of LI-RADS TRA when using CT versus using HBA-enhanced MRI in an intraindividual manner according to pathologic results. Materials and Methods Between January 2011 and September 2019, 165 patients with 237 clinically suspected HCCs underwent LRT followed by LT and were retrospectively included. All patients underwent both CT and HBA-enhanced MRI after LRT and before LT. Three radiologists independently assessed tumor viability with both modalities by using LI-RADS TRA and reached a consensus. Pathologic tumor viability categorized as either completely (100%) or incompletely (

To investigate an additional value of [68Ga]Ga-DOTA-TOC PET/CT for characterizing suspected pancreatic neuroendocrine neoplasms (NENs) in a large study cohort. This retrospective study included 167 patients who underwent [68Ga]Ga-DOTA-TOC PET/CT for suspected pancreatic NENs detected by contrast-enhanced CT (n = 153) and/or MRI (n = 85). Two board-certified radiologists independently reviewed CT and/or MRI as well as [68Ga]Ga-DOTA-TOC PET/CT and scored the probability of NEN on a 5-point scale. Radiologists’ diagnostic performances with and without [68Ga]Ga-DOTA-TOC PET/CT were compared using pathologic findings as the standard of reference. All 167 patients were pathologically diagnosed with NENs (n = 131) or non-NENs (n = 36) by surgery (n = 93) or biopsy (n = 74). The non-NEN group included focal pancreatitis (n = 7), gastrointestinal stromal tumor (n = 6), serous cystadenoma (n = 5), metastatic renal cell carcinoma (n = 4), intrapancreatic accessory spleen (n = 4), ductal adenocarcinoma (n = 3), solid pseudopapillary neoplasm (n = 2), intraductal papillary mucinous carcinoma (n = 1), adenosquamous carcinoma (n = 1), schwannoma (n = 1), paraganglioma (n = 1), and solitary fibrous tumor (n = 1). Radiologists’ diagnostic performance significantly improved after the addition of [68Ga]Ga-DOTA-TOC PET/CT (AUC of CT: 0.737 vs. 0.886 for reviewer 1 [p = 0.0004]; 0.709 vs. 0.859 for reviewer 2 [p = 0.0002], AUC of MRI: 0.748 vs. 0.872 for reviewer 1 [p = 0.023]; 0.670 vs. 0.854 for reviewer 2 [p = 0.001]). [68Ga]Ga-DOTA-TOC PET/CT significantly improved sensitivity (CT: 87.4% vs. 96.6% for reviewer 1 [p = 0.001]; 74.8% vs. 92.5% for reviewer 2 [p = 0.0001], MRI: 86.9% vs. 98.4% for reviewer 1 [p = 0.016]; 70.5% vs. 91.8% for reviewer 2 [p = 0.002]). [68Ga]Ga-DOTA-TOC PET/CT provided an additional value over conventional CT or MRI for the characterization of suspected pancreatic NENs. • [ 68 Ga]Ga-DOTA-TOC PET/CT could provide additional value over conventional CT and/or MRI for the exact characterization of suspected pancreatic NENs by increasing AUC values and sensitivity. • Diagnostic improvement was significant, especially in NENs showing an atypical enhancement pattern. • The inter-observer agreement was improved when [ 68 Ga]Ga-DOTA-TOC PET/CT was added to CT and/or MRI.

To compare lesion conspicuity and image quality of arterial phase images obtained from low kVp (90-kVp) and dual-energy (DE) scans for the evaluation of hypervascular hepatocellular carcinoma (HCC). This retrospective study included 229 patients with HCC who underwent either 90 kVp (n = 106) or DE scan (80- and 150-kVp with a tin filter) (n = 123) during the arterial phase. DE scans were reconstructed into a linearly blended image with a mixed ratio of 0.6 (60% 80kVp and 40% 150 kVp) and post-processed for 40 keV and 50 keV images. The contrast-to-noise ratio (CNR) of HCC to the liver and image noise was measured. Lesion conspicuity, liver parenchymal image quality, and overall image preference were assessed qualitatively by three independent radiologists. DE 40 keV images had the highest CNR of HCC, and DE blended images had the lowest image noise among four image sets (p = 0.01 and p 0.05). For qualitative analyses, DE blended images had the highest scores for image quality and overall image preference (ps

This study was aimed at investigating the clinical feasibility of quantitative ultrasound (QUS) imaging in the evaluation of suspected hepatic steatosis through assessment of the reliability of measurements and its correlation with the controlled attenuation parameter (CAP). This retrospective study included 117 patients who underwent liver B-mode ultrasound (US) with QUS imaging with a clinical US machine (RS85, Samsung Medison, Seoul, Korea) and CAP measurements between December 2019 and March 2020. For QUS examination, tissue attenuation imaging (TAI) and tissue scatter-distribution imaging (TSI) parameters were obtained. Intra- and inter-examiner reliability were assessed using intra-class correlation coefficients (ICCs), and QUS imaging parameters were correlated with CAP measurements using Spearman's correlation analysis. TAI and TSI revealed excellent intra- and inter-examiner reliability with ICCs of 0.994 and 0.975 and 0.991 and 0.947, respectively. Both TAI and TSI were significantly positively correlated with CAP values. QUS imaging provided good intra-and inter-observer reliability and correlated well with CAP in assessing suspected hepatic steatosis.

OBJECTIVE To investigate the diagnostic performance of quantitative ultrasound (US) parameters for the assessment of hepatic steatosis in patients with nonalcoholic fatty liver disease (NAFLD) using magnetic resonance imaging proton density fat fraction (MRI-PDFF) as the reference standard. MATERIALS AND METHODS In this single-center prospective study, 120 patients with clinically suspected NAFLD were enrolled between March 2019 and January 2020. The participants underwent US examination for radiofrequency (RF) data acquisition and chemical shift-encoded liver MRI for PDFF measurement. Using the RF data analysis, the attenuation coefficient (AC) based on tissue attenuation imaging (TAI) (AC-TAI) and scatter-distribution coefficient (SC) based on tissue scatter-distribution imaging (TSI) (SC-TSI) were measured. The correlations between the quantitative US parameters (AC and SC) and MRI-PDFF were evaluated using Pearson correlation coefficients. The diagnostic performance of AC-TAI and SC-TSI for detecting hepatic fat contents of ≥ 5% (MRI-PDFF ≥ 5%) and ≥ 10% (MRI-PDFF ≥ 10%) were assessed using receiver operating characteristic (ROC) analysis. The significant clinical or imaging factors associated with AC and SC were analyzed using linear regression analysis. RESULTS The participants were classified based on MRI-PDFF: < 5% (n = 38), 5-10% (n = 23), and ≥ 10% (n = 59). AC-TAI and SC-TSI were significantly correlated with MRI-PDFF (r = 0.659 and 0.727, p < 0.001 for both). For detecting hepatic fat contents of ≥ 5% and ≥ 10%, the areas under the ROC curves of AC-TAI were 0.861 (95% confidence interval [CI]: 0.786-0.918) and 0.835 (95% CI: 0.757-0.897), and those of SC-TSI were 0.964 (95% CI: 0.913-0.989) and 0.935 (95% CI: 0.875-0.972), respectively. Multivariable linear regression analysis showed that MRI-PDFF was an independent determinant of AC-TAI and SC-TSI. CONCLUSION AC-TAI and SC-TSI derived from quantitative US RF data analysis yielded a good correlation with MRI-PDFF and provided good performance for detecting hepatic steatosis and assessing its severity in NAFLD.

Purpose: This study aimed to investigate and categorize the diverse features of hepatic hemangiomas on superb microvascular imaging (SMI) in a relatively large prospective study.Methods: In this prospective study, 70 patients with 92 hepatic hemangiomas were consecutively enrolled. All nodules were radiologically confirmed with the typical imaging features of hepatic hemangiomas on dynamic computed tomography (CT) or magnetic resonance imaging (MRI). Using SMI, all lesions were evaluated and categorized into subgroups according to the flow pattern on SMI. Differences in the frequencies of SMI patterns according to lesion size and enhancement patterns on dynamic CT or MRI were also compared.Results: In 67.4% (62/92) of hemangiomas, tumor vascularity was detected using SMI, while 32.6% (30/92) did not show any signal on the SMI examination, and the absence of an SMI signal was not shown in rapidly enhancing hemangiomas (0% [0/30] vs. 100% [30/30], P=0.002) and was more frequent in lesions

To investigate the utility of MR findings and texture analysis for predicting the malignant potential of pancreatic intraductal papillary mucinous neoplasms (IPMNs). Two hundred forty-eight patients with surgically confirmed IPMNs (106 malignant [invasive carcinoma/high-grade dysplasia] and 142 benign [low/intermediate-grade dysplasia]) and who underwent magnetic resonance imaging (MRI) with MR cholangiopancreatography (MRCP) were included. Two reviewers independently analyzed MR findings as proposed by the 2017 international consensus guidelines. Texture analysis of MRCP was also performed. A multivariate logistic regression analysis was used to identify predictors for malignant IPMNs. Diagnostic performance was also analyzed using receiver operating curve analysis. Among MR findings, enhancing mural nodule size ≥ 5 mm, main pancreatic duct (MPD) ≥ 10 mm or MPD of 5 to 9 mm, and abrupt change of MPD were significant predictors for malignant IPMNs (p

To predict poor survival and tumor recurrence in patients with ampullary adenocarcinoma using preoperative clinical and CT findings. A total of 216 patients with ampullary adenocarcinoma who underwent preoperative CT and surgery were retrospectively included. CT was assessed by two radiologists. Clinical and histopathological characteristics including histologic subtypes were investigated. A Cox proportional hazard model and the Kaplan-Meier method were used to identify disease-free survival (DFS) and overall survival (OS). A nomogram was created based on the multivariate analysis. The optimal cutoff size of the tumor was evaluated and validated by internal cross validation. The median OS was 62.8 ± 37.9, and the median DFS was 54.3 ± 41.2 months. For OS, tumor size (hazard ratio [HR] 2.79, p

To compare the diagnostic performances of first and second portal venous phases (PVP1 and PVP2) in revealing washout and capsule appearance for non-invasive HCC diagnoses in gadoxetic acid–enhanced MRI (Gd-EOB-MRI). This retrospective study included 123 at-risk patients with 160 hepatic observations (HCCs, n = 116; non-HCC malignancies, n = 18; benign, n = 26) showing arterial phase hyper-enhancement (APHE) ≥ 1 cm at Gd-EOB-MRI. The mean time intervals from gadoxetic acid injection to PVP1 and PVP2 acquisitions were 53 ± 2 s and 73 ± 3 s, respectively. After evaluating image findings independently, imaging findings and diagnoses were finalized by a consensus of two radiologists using either PVP1 or PVP2 image sets according to the LI-RADS v2018 or EASL criteria. Sensitivity, specificity, and accuracy were compared. Among HCCs, more washout and enhancing capsule were observed in PVP2 (83.6% and 27.6%) than in PVP1 (50.9% and 19.8%) (p

Multiphasic CT or MRI and serum alpha-fetoprotein (AFP) are widely used for posttreatment surveillance of hepatocellular carcinoma (HCC). This study aimed to investigate the clinical outcomes of patients with high posttreatment AFP but without evident recurrence on CT or MRI after curative-intent treatment of HCC. We retrospectively analyzed 121 patients presenting with high posttreatment AFP (> 20 ng/mL) without evident recurrence on multiphasic CT or MRI during surveillance after curative-intent surgical resection or radiofrequency ablation (RFA) for HCC. The time interval from the first event of high posttreatment AFP to imaging-evident recurrence (TimeAFP-Imaging recurrence) was estimated using the Kaplan–Meier method. Cox regression analyses were performed to assess the associated factors with TimeAFP-Imaging recurrence. The median TimeAFP-Imaging recurrence was 20.0 months (95% CI 13.0–28.0 months), and the estimated 6-month and 1-year cumulative incidences of imaging-evident recurrence were 24.4% and 40.1%, respectively. In multivariate Cox analyses, late onset of AFP elevation (> 3 months after treatment) was an independent predictor of shorter TimeAFP-Imaging recurrence (HR 2.11, P = 0.015) if using variables available at the first event of AFP elevation, while non-normalization of AFP at the next follow-up was an independent predictor of shorter TimeAFP-Imaging recurrence (HR 3.65, P

To investigate the diagnostic performance of liver stiffness (LS) measurements on two-dimensional (2D) shear wave elastography (SWE) for the assessment of hepatic fibrosis using LS measurements on MR elastography (MRE) as the reference standard and the prediction of clinically significant portal hypertension (CSPH).In this prospective study, 101 patients with chronic liver disease or cirrhosis underwent both MRE and SWE. After exclusion of technical failure on MRE (n = 5), technical failure/unreliable measurement on SWE (n = 4), LS measurements obtained on SWE with the aid of propagation maps were correlated with those of the MRE using Pearson's correlation analysis. Diagnostic performances for significant fibrosis (≥F2: MRE of ≥2.99 kPa) or cirrhosis (F4: MRE of ≥3.63 kPa) and for the prediction of CSPH were assessed using receiver operating characteristics (ROC) curve analysis.LS values on SWE showed a strong correlation with those on MRE (r = 0.846, P0.001). For the diagnosis of significant fibrosis or cirrhosis in patients with hepatitis B virus-related liver disease (n = 75), SWE showed areas under the ROC curves (AUC) of 0.975 and 0.912, respectively (95% confidence interval [CI], 0.910-997, and 0.824-0.965). For the prediction of CSPH, the AUC of SWE was 0.818 (95% CI, 0.712-0.898), and when an LS value of 11.5 kPa was applied as a cut-off, SWE showed a sensitivity of 81.5% and a specificity of 72.9%.LS measurements on 2D SWE were demonstrated to be well correlated with those obtained with MRE, and thus, may provide good diagnostic performance for the prediction of hepatic fibrosis and the presence of CSPH.

To evaluate diagnostic values of the liver imaging reporting and data system (LI-RADS) M (LR-M) category based on novel explicit criteria that accept both targetoid and nontargetoid LR-M features and the suggested reporting algorithm of LI-RADS v2018 to assess primary liver cancers (PLCs) on gadoxetic acid-enhanced MRI (Gd-EOB-MRI). This retrospective study included 165 patients at high risk for hepatocellular carcinoma (HCC) with pathologically confirmed PLCs (HCC, n = 113; intrahepatic cholangiocarcinoma [iCCA], n = 23; and combined hepatocellular cholangiocarcinoma [cHCC-CCA], n = 29). Two radiologists independently analyzed Gd-EOB-MRI features and determined LI-RADS category for each tumor and categorized the likely etiology either as HCC or non-HCC malignancy if LR-M was assigned. Diagnostic performances for HCC or those for malignancy were compared according to imaging criteria. LR-M was assigned in 95.7%/91.3% of iCCAs; 55.2%/58.6% of cHCC-CCAs; and 21.2%/17.7% of HCCs in reviewers 1/2. Combination of LR-5 plus LR-M resulted in sensitivity of 95.2%/97.6% to diagnose PLCs as malignant, which were significantly higher than that of LR-5 plus “LR-M with ≥ 1 targetoid appearances” (84.8%/91.5%, Ps

This study was conducted in order to assess the performance of the Liver Imaging Reporting and Data System (LI-RADS) treatment response (TR) (LR-TR) categorization on gadoxetic acid-enhanced MRI (Gd-EOB-MRI) for detecting viable tumors in hepatocellular carcinoma (HCC) treated with locoregional treatment (LRT) and to investigate the added value of ancillary features (AFs) to conventional enhancement-based criteria.This retrospective study included 183 patients with Gd-EOB-MRI after LRT for HCC and appropriate reference standards for tumor viability (84 viable and 99 nonviable). Two independent radiologists assigned per-lesion mRECIST and TR categories (TR-nonviable, TR-equivocal, or TR-viable) according to the LR-TR algorithm and modified LR-TR algorithms including mLR-TR(TP) allowing transitional phase (TP) washout and mLR-TR(AF) allowing category adjustment by applying AFs. Diagnostic performances of imaging criteria were compared using the Cochran's Q test with post hoc analysis.For detecting viable tumors, LR-TR-viable resulted in sensitivities of 64.5%/39.3% and specificities of 98.0%/98.0% in reviewers 1/2. In comparison to LR-TR-viable, mRECIST-viable, mLR-TR(TP)-viable, and mLR-TR(AF)-viable showed significantly higher sensitivities (92.9%/94.0%, 77.4%/56.6%, and 86.9%/83.3% in reviewers 1/2) (ps 0.001). The specificity of mRECIST-viable (73.7%/62.6%) was significantly lower than that of LR-TR-viable (ps 0.001), while those of mLR-TR(TP)-viable and mLR-TR(AF)-viable were greater than 95% (98.0%/96.0% and 97.0%/96.0%), statistically equivalent to LR-TR-viable (ps 0.05). TR-equivocal was least assigned on mLR-TR(AF) (1.1%/7.7%) than LR-TR (15.8%/32.2%) or mLR-TR(TP) (6.6%/23.5%) in both reviewers.The LR-TR algorithm on Gd-EOB-MRI provides a specific diagnosis of viable tumor but with limited sensitivity. By applying AFs in the category adjustment, more sensitive and confident diagnosis can be achieved without significant loss of specificity.• The LI-RADS treatment response (LR-TR) algorithm on Gd-EOB-MRI provides a highly specific diagnosis of viable HCC but with limited sensitivity. • The inferior sensitivity of LR-TR-viable category to that of mRECIST can be improved by applying ancillary features in the category adjustment.

PURPOSE The purpose of this study was to compare the sensitivity of MicroFlow Imaging (MFI) with that of color and power Doppler imaging (CDI and PDI, respectively) in detecting the vascularity of hepatocellular carcinomas (HCCs). METHODS This prospective study enrolled 51 patients diagnosed with HCC between August 2018 and December 2018. CDI, PDI, MFI, and contrast-enhanced ultrasound (CEUS) were performed. Two radiologists evaluated the presence and pattern of tumoral vascularity on CDI, PDI, and MFI. Vascular presence was graded on a 5-point scale (0, absent; 4, >50% of the tumor). The vascular pattern was chosen from following categories: basket, vessels in tumor, spot, detouring, mixed, or others. Two additional radiologists assessed CEUS images for the presence and pattern of tumoral vascularity, which served as the reference standard. If the tumoral vascular pattern on each examination matched that of the CEUS images, the Wilcoxon test and McNemar test, respectively, were used to compare the sensitivity for detecting tumoral vascularity between MFI and CDI, and between MFI and PDI. Logistic regression analysis was performed to identify factors associated with MFI detectability of tumoral vascularity. RESULTS CEUS demonstrated tumoral vascularity in 98.0% (50 of 51) of patients. MFI (58.0%, 29 of 50) demonstrated a higher sensitivity than CDI (14.0%, 7 of 50) or PDI (14.0%, 7 of 50) (P

To evaluate the additional value of superb microvascular imaging (SMI) to characterize focal liver lesions (FLLs).Between July 2020 and December 2020, 70 patients (39 men and 31 women; mean age [± standard deviation], 61.1 ± 10.1 years) with FLLs were prospectively enrolled and underwent B-mode ultrasound (US), color Doppler imaging (CDI), power Doppler imaging (PDI), and SMI examinations on the same day. All the malignant FLLs were confirmed by histological diagnosis, while the benign FLLs were confirmed by typical imaging features at contrast-enhanced CT and/or MRI. Tumor vascularity scores in CDI, PDI, and SMI were graded using a 5-point scale. For tumors in which vascularity was detected on SMI, tumor vascular pattern on SMI was assessed in each lesion. The diagnostic performance of a combination of B-mode US and SMI, based on vascular pattern on SMI, was compared to B-mode US alone to diagnose malignant lesions; and hemangiomas.Seventy FLLs (34 benign [31 hemangiomas, 3 focal nodular hyperplasias] and 36 malignant tumors [16 hepatocellular carcinomas, 10 cholangiocarcinomas, 10 metastases]) were enrolled. Tumor vascularity score in SMI was significantly higher than those in CDI and PDI (P 0.001). Using a combination of B-mode US and SMI, the diagnostic performance was improved from 0.867 and 0.834 to 0.945 and 0.921 (P = 0.035 and 0.112) to diagnose malignant tumors and from 0.896 and 0.853 to 0.975 and 0.987 (P = 0.027 and 0.006) to diagnose hemangiomas by reviewers 1 and 2, respectively.SMI provides higher sensitivity than CDI and PDI to detect tumor vascularity, and a combination of B-mode US and SMI can improve the characterization of FLLs when vascular pattern of tumor is considered.

To determine the impact of dedicated subspecialized radiologists in multidisciplinary team (MDT) discussions on the management of lower gastrointestinal (GI) tract malignancies.We retrospectively analyzed the data of 244 patients (mean age ± standard deviation, 61.7 ± 11.9 years) referred to MDT discussions 249 times (i.e., 249 cases, as five patients were discussed twice for different issues) for lower GI tract malignancy including colorectal cancer, small bowel cancer, GI stromal tumor, and GI neuroendocrine tumor between April 2018 and June 2021 in a prospective database. Before the MDT discussions, dedicated GI radiologists reviewed all imaging studies again besides routine clinical reading. The referring clinician's initial diagnosis, initial treatment plan, change in radiologic interpretation compared with the initial radiology report, and the MDT's consensus recommendations for treatment were collected and compared. Factors associated with changes in treatment plans and the implementation of MDT decisions were analyzed.Of the 249 cases, radiologic interpretation was changed in 73 cases (29.3%) after a review by dedicated GI radiologists, with 78.1% (57/73) resulting in changes in the treatment plan. The treatment plan was changed in 92 cases (36.9%), and the rate of change in the treatment plan was significantly higher in cases with changes in radiologic interpretation than in those without (78.1% [57/73] vs. 19.9% [35/176],MDT discussion involving additional review of radiology examinations by dedicated GI radiologists resulted in a change in the treatment plan in 36.9% of cases. Changes in treatment plans were significantly associated with changes in radiologic interpretation.

Purpose: This study aimed to assess the inter-platform reproducibility of ultrasound attenuation examination in patients with nonalcoholic fatty liver disease (NAFLD).Methods: Between March 2021 and April 2021, patients with clinically suspected or known NAFLD were prospectively enrolled; each patient underwent ultrasound attenuation examinations with three different platforms (Attenuation Imaging [ATI], Canon Medical System; Tissue Attenuation Imaging [TAI], Samsung Medison; and Ultrasound-Guided Attenuation Parameter [UGAP], GE Healthcare) on the same day. The mean attenuation coefficient (AC) values of the three platforms were compared using repeated-measures analysis of variance with the Bonferroni correction. To evaluate inter-platform reproducibility, the AC values obtained for each platform were compared using Bland-Altman analysis with the calculation of 95% limits of agreement (LOA), intraclass correlation coefficients (ICCs), and coefficients of variation (CVs).Results: Forty-six patients (23 men; mean age±standard deviation, 52.3±12.4 years) were enrolled. The mean AC values showed significant differences among the three platforms (0.75±0.12, 0.80±0.11, and 0.74±0.09 dB/cm/MHz for ATI, TAI, and UGAP, respectively; P

Objectives To compare the virtual non-contrast (VNC) images acquired through dual-energy computed tomography (DECT) with the true non-contrast (TNC) images in the detection of biliary stones and to calculate dose reduction by replacing TNC images with VNC images. Methods Between March 2017 and April 2018, we retrospectively enrolled 75 patients with suspicious biliary disease who underwent dual-source DECT and surgery and/or endoscopic intervention within 2 months from the CT. Biliary stones were present in 45 patients. The sensitivity and specificity for detecting gallstone and common bile duct (CBD) stone were compared between the VNC and TNC using McNemar test. In addition, the possible reduction in radiation dose was calculated. Results In our study, 37 patients had gallstones, 2 had CBD stones, and 6 had both gallstone and CBD stones. For detection of gallstones, the sensitivity and specificity were 90.7% (39/43) and 87.5% (28/32), respectively, for the TNC images, and 88.4% (38/43) and 90.6% (29/32), respectively, for the VNC images. With respect to CBD stones, the sensitivity and specificity were 87.5% (7/8) and 98.5% (66/67), respectively, for the TNC images, and 75.0% (6/8) and 100% (67/67), respectively, for the VNC images. There was no significant difference in the sensitivity and specificity between each image set (P > 0.05). The radiation dose reduction of 22.4 ± 1.3% is expected by omitting TNC images. Conclusions The VNC images derived from DECT were comparable to the TNC images for the detection of biliary stones and may replace the TNC images to reduce radiation dose.

Objective To determine the feasibility of microvascular flow imaging (MVFI) in comparison with color/power Doppler imaging (CDI/PDI) for detection of intratumoral vascularity in suspected post-transarterial chemoembolization (TACE) residual or recurrent hepatocellular carcinomas (HCCs) by using contrast-enhanced ultrasonography (CEUS) or hepatic angiography (HA) findings as the reference standard. Materials and Methods One hundred HCCs (mean size, 2.2 cm) in 100 patients treated with TACE were included in this prospective study. CDI, PDI, and MVFI were performed in tandem for evaluating intratumoral vascularity of the lesions by using an RS85 ultrasound scanner (Samsung Medison Co., Ltd.). Intratumoral vascularity in each technique was assessed by two radiologists in consensus by using a 5-point scale. Then, one of the two radiologists and another radiologist performed additional image review in the reverse order (MVFI-PDI-CDI) for evaluation of intra- and interobserver agreements. Results were then compared with those of either HA or CEUS as the reference. The McNemar test, logistic regression analysis, and intraclass correlation coefficient (ICC) were used. Results CEUS or HA revealed intratumoral vascularity in 87% (87/100) of the tumors. Sensitivity (79.3%, 69/87) and accuracy (80.0%, 80/100) of MVFI were significantly higher than those of CDI (sensitivity, 27.6% [24/87]; accuracy, 37.0% [37/100]) or PDI (sensitivity, 36.8% [32/87]; accuracy, 44.0% [44/100]) (all p < 0.05). CDI, PDI, and MVFI presented excellent intraobserver (ICCs > 0.9) and good interobserver agreements (ICCs > 0.6). Conclusion MVFI demonstrated significantly higher sensitivity and accuracy than did CDI and PDI for the detection of intratumoral vascularity in suspected residual or recurrent HCCs after TACE.

The purpose of our study was to investigate the diagnostic performance of 2-D ultrasound attenuation imaging (ATI) for the assessment of hepatic steatosis in patients with chronic liver disease using magnetic resonance imaging proton density fat fraction (MRI-PDFF) as the reference standard. We prospectively analyzed 87 patients with chronic liver disease who had reliable measurements at both ATI and MRI-PDFF. For the detection of hepatic steatosis of MRI-PDFF ≥5% and MRI-PDFF ≥10%, ATI measurements yielded areas under the receiver operating characteristic curve of 0.76 and 0.88, respectively (95% confidence intervals: 0.66–0.85 and 0.79–0.94). Attenuation coefficients at ATI were moderately correlated with MRI-PDFF (ρ = 0.66). In conclusion, attenuation coefficients at ultrasound ATI were well correlated with MRI-PDFF and, thus, may provide good diagnostic performance in the assessment of hepatic steatosis, making these coefficients a promising tool for the non-invasive assessment and quantification of hepatic steatosis.

To identify features on preoperative MR imaging with diffusion-weighted imaging (DWI) for predicting next-generation sequencing (NGS)-based tumor cellularity and patient outcome after surgical resection of pancreatic ductal adenocarcinoma (PDAC).This retrospective study included 105 patients with surgically resected PDAC who underwent preoperative MR imaging with DWI. Tumor cellularity was measured using molecular techniques and bioinformatics methods. Clinico-pathologic findings including tumor T stage for predicting disease-free survival (DFS) and overall survival (OS) were identified using Cox proportional hazards model. Important MR imaging findings including apparent diffusion coefficient (ADC) value of PDAC and modified ADC value (the ratio of the ADC value of PDAC to the ADC value of the spleen) for predicting higher tumor cellularity (≥ 30%) and poor prognosis were also identified.The median DFS and OS were 12.0 months [95% confidence interval (CI), 8.0-17.0] and 22.0 months (95% CI, 18.0-29.0), respectively. Higher T stage (T3/4) [hazard ratio (HR), 7.720, (95% CI 1.072, 55.612); p = 0.048] and higher tumor cellularity [HR, 1.599 (95% CI, 1.003-2.548); p = 0.048] were significantly associated with worse DFS. Among MR imaging features, the modified ADC value was significantly associated with tumor cellularity [odds ratio, 0.068 (95% CI, 0.012-0.372); p = 0.002], and PDAC with lower modified ADC value [≤ 1.40 (cutoff value)] showed significantly shorter median DFS than PDAC with higher modified ADC value [8 months (95% CI, 4-12) vs. 16 months (95% CI, 10-29); HR, 1.713 (95% CI, 1.073-2.735), log-rank p = 0.024].Higher NGS-based tumor cellularity may be a negative prognostic factor in pancreatic cancer after resection, and modified ADC value derived from DWI could be helpful in predicting tumor cellularity and patient surgical outcome with regard to recurrence.

To investigate clinical and CT factors associated with local resectability in patients with nonmetastatic pancreatic cancers after neoadjuvant chemotherapy ± radiation therapy (CRT). This retrospective study included consecutive patients with nonmetastatic pancreatic cancers who underwent neoadjuvant CRT between June 2009 and June 2019. Tumor size, tumor-vascular contact with artery/vein, and local resectability categories (resectable, borderline resectable, or locally advanced) were assessed at baseline and post-CRT CT. Baseline and post-CRT carbohydrate antigen (CA) 19-9 levels were also assessed. Clinical or imaging features related to R0 resection were determined using logistic regression analysis. A total of 179 patients (mean age, 62.4 ± 9.3 years; 92 men) were included. After neoadjuvant CRT, 105 (58.7%) patients received R0 resection, while 74 (41.3%) did not. R0 resection rates were significantly different according to post-CRT CT resectability categories (p < 0.001): 82.8% (48/58), 70.1% (47/67), and 18.5% (10/54) for resectable, borderline resectable, and locally advanced disease, respectively. For post-CRT borderline resectable disease, ≥ 50% decrease in CA 19-9 was significantly associated with R0 resection (odds ratio (OR), 3.160; p = 0.02). For post-CRT locally advanced disease, small post-CRT tumor size ≤ 2 cm (OR, 9.668; p = 0.026) and decreased tumor-arterial contact (OR, 24.213; p = 0.022) were significantly associated with R0 resection. Post-CRT CT resectability categorization may be useful for the assessment of R0 resectability in patients with pancreatic cancer following neoadjuvant CRT. Additionally, ≥ 50% decrease in CA 19-9 was associated with R0 resection in post-CRT borderline resectable disease, while small post-CRT tumor size and decreased tumor-arterial contact were with locally advanced disease. • R0 resection rates following neoadjuvant chemotherapy ± radiation therapy (CRT) were 82.8%, 70.1%, and 18.5% in resectable, borderline resectable, and locally advanced disease, respectively, at post-CRT CT (p < 0.001). • For post-CRT borderline resectable disease, ≥ 50% decrease in carbohydrate antigen (CA) 19-9 was significantly associated with R0 resection. • For post-CRT locally advanced disease, small post-CRT tumor size ≤ 2 cm and decreased tumor-arterial contact were significantly associated with R0 resection.

To explain the new changes in pathologic diagnoses of biphenotypic primary liver cancer (PLC) according to the updated 2019 World Health Organization (WHO) classification and how it impacts Liver Imaging Reporting and Data System (LI-RADS) classification using gadoxetic acid–enhanced MRI (Gd-EOB-MRI). We retrospectively included 209 patients with pathologically proven biphenotypic PLCs according to the 2010 WHO classification who had undergone preoperative Gd-EOB-MRI between January 2009 and December 2018. Imaging analysis including LI-RADS classification and pathologic review including the proportion of tumor components were performed. Frequencies of each diagnosis and subtype according to the 2010 and 2019 WHO classifications were compared, and changes in LI-RADS classification were evaluated. Univariable and multivariable analysis were performed to determine significant tumor component for LI-RADS classification. Of the 209 biphenotypic PLCs of the 2010 WHO classification, 177 (84.7%) were diagnosed as bipheonotypic PLCs, 25 (12.0%) as hepatocellular carcinomas (HCCs), and 7 (3.3%) as cholangiocarcinomas (CCAs) using the 2019 WHO classification. Of the 177 biphenotypic PLCs, LR-M, LR-4, and LR-5 were assigned in 77 (43.5%), 21 (11.9%), and 63 (35.5%), respectively. There were no significant differences in the proportion of LR-5 and LR-M categories between the WHO 2010 and 2019 classifications (p = 0.941). Proportion of HCC component was the only independent factor for LI-RADS classification (adjusted odds ratio, 1.02; p < 0.001). According to the 2019 WHO classification, 15% of biphenotypic PLCs from the 2010 WHO classification were re-diagnosed as HCCs or CCAs, and a substantial proportion of biphenotypic PLCs of the 2019 WHO classification could be categorized as LR-4 or LR-5 on Gd-EOB-MRI. • Among 209 diagnosed biphenotypic PLCs according to the 2010 WHO classification, 177 (84.7%) lesions were reclassified as bipheonotypic PLCs, 25 (12.0%) as HCCs, and 7 (3.3%) as CCAs using the 2019 WHO classification. • Of the 177 biphenotypic PLCs at the 2019 WHO classification, LR-M, LR-4, and LR-5 were assigned in 77 (43.5%), 21 (11.9%), and 63 (35.5%), respectively. • LI-RADS classification relied on the proportion of HCC component (adjusted odds ratio,1.02; p < 0.001).

To compare lesion conspicuity and image quality of arterial phase images obtained from low kVp (90-kVp) and dual-energy (DE) scans for the evaluation of hypervascular hepatocellular carcinoma (HCC).This retrospective study included 229 patients with HCC who underwent either 90 kVp (n = 106) or DE scan (80- and 150-kVp with a tin filter) (n = 123) during the arterial phase. DE scans were reconstructed into a linearly blended image with a mixed ratio of 0.6 (60% 80kVp and 40% 150 kVp) and post-processed for 40 keV and 50 keV images. The contrast-to-noise ratio (CNR) of HCC to the liver and image noise was measured. Lesion conspicuity, liver parenchymal image quality, and overall image preference were assessed qualitatively by three independent radiologists.DE 40 keV images had the highest CNR of HCC, and DE blended images had the lowest image noise among four image sets (p = 0.01 and p 0.001, respectively). There was no significant difference in mean volume CT dose index and dose-length product between DE and low kVp scan (ps 0.05). For qualitative analyses, DE blended images had the highest scores for image quality and overall image preference (ps 0.001).At an equal radiation dose, DE 40 keV showed higher CNR of HCC and DE blended image showed higher image quality and image preference compared with low kVp CT.

To predict poor survival and tumor recurrence in patients with ampullary adenocarcinoma using preoperative clinical and CT findings.A total of 216 patients with ampullary adenocarcinoma who underwent preoperative CT and surgery were retrospectively included. CT was assessed by two radiologists. Clinical and histopathological characteristics including histologic subtypes were investigated. A Cox proportional hazard model and the Kaplan-Meier method were used to identify disease-free survival (DFS) and overall survival (OS). A nomogram was created based on the multivariate analysis. The optimal cutoff size of the tumor was evaluated and validated by internal cross validation.The median OS was 62.8 ± 37.9, and the median DFS was 54.3 ± 41.2 months. For OS, tumor size (hazard ratio [HR] 2.79, p 0.001), papillary bulging (HR 0.63, p = 0.049), organ invasion on CT (HR 1.92, p = 0.04), male sex (HR 1.59, p = 0.046), elevated CA 19-9 (HR 1.92, p = 0.01), pT stage (HR 2.45, p = 0.001), and pN stage (HR 3.04, p 0.001) were important predictors of survival. In terms of recurrence, tumor size (HR 2.37, p = 0.04), pT stage (HR 1.76, p = 0.03), pN stage (HR 2.23, p = 0.001), and histologic differentiation (HR 4.31, p = 0.008) were important predictors of recurrence. In terms of tumor size on CT, 2.65 cm and 3.15 cm were significant cutoff values for poor OS and RFS (p 0.001).Preoperative clinical and CT findings were useful to predict the outcomes of ampullary adenocarcinoma. In particular, tumor size, papillary bulging, organ invasion on CT, male sex, and elevated CA 19-9 were important predictors of poor survival after surgery.• Clinical staging based on preoperative clinical information and CT findings can be useful to predict the prognosis of ampullary adenocarcinoma patients. • In terms of survival, tumor size (HR 2.79), papillary bulging (HR 0.63), organ invasion on CT (HR 1.92), male sex (HR 1.59), and elevated CA 19-9 (HR 1.92) were important clinical predictors of poor survival. • Tumor size on CT was of special importance for both poor overall survival and disease-free survival, with optimal cutoff values of 2.65 cm and 3.15 cm, respectively (p 0.001).

Multiphasic CT or MRI and serum alpha-fetoprotein (AFP) are widely used for posttreatment surveillance of hepatocellular carcinoma (HCC). This study aimed to investigate the clinical outcomes of patients with high posttreatment AFP but without evident recurrence on CT or MRI after curative-intent treatment of HCC.We retrospectively analyzed 121 patients presenting with high posttreatment AFP ( 20 ng/mL) without evident recurrence on multiphasic CT or MRI during surveillance after curative-intent surgical resection or radiofrequency ablation (RFA) for HCC. The time interval from the first event of high posttreatment AFP to imaging-evident recurrence (TimeThe median TimeIn the surveillance setting after curative-intent treatment of HCC, patients presenting with high posttreatment AFP without evident recurrence on CT or MRI may frequently progress to imaging-evident recurrence. In high-risk patients, an extensive diagnostic workup or close monitoring is needed to detect HCC recurrence earlier.

To compare the diagnostic performances of first and second portal venous phases (PVP1 and PVP2) in revealing washout and capsule appearance for non-invasive HCC diagnoses in gadoxetic acid-enhanced MRI (Gd-EOB-MRI).This retrospective study included 123 at-risk patients with 160 hepatic observations (HCCs, n = 116; non-HCC malignancies, n = 18; benign, n = 26) showing arterial phase hyper-enhancement (APHE) ≥ 1 cm at Gd-EOB-MRI. The mean time intervals from gadoxetic acid injection to PVP1 and PVP2 acquisitions were 53 ± 2 s and 73 ± 3 s, respectively. After evaluating image findings independently, imaging findings and diagnoses were finalized by a consensus of two radiologists using either PVP1 or PVP2 image sets according to the LI-RADS v2018 or EASL criteria. Sensitivity, specificity, and accuracy were compared.Among HCCs, more washout and enhancing capsule were observed in PVP2 (83.6% and 27.6%) than in PVP1 (50.9% and 19.8%) (p 0.001, both). The PVP2 set presented significantly higher sensitivity (83.6% vs. 53.5%, LI-RADS; 82.8% vs. 50.0%, EASL; p 0.001, both) and accuracy (0.88 vs. 0.73, LI-RADS; 0.88 vs. 0.72, EASL; p 0.001, both) than the PVP1 set without significant specificity loss (93.2% vs. 93.2%, by LI-RADS or EASL; p = 0.32, both). None of the non-HCC malignancy was non-invasively diagnosed as HCC in both PVP image sets.Late acquisition of PVP detected washout and enhancing capsule of HCC more sensitively than early acquisition, enabling accurate diagnoses of HCC, according to LI-RADS or EASL criteria.• Among HCCs, more washout and enhancing capsules were observed in PVP2 than PVP1, quantitatively and qualitatively. • The portal venous phase acquired at around 70 s after contrast media administration (PVP2) provided significantly higher sensitivity and AUC value than PVP1 by using LI-RADS v2018 or EASL criteria. • More HCCs were categorized as LR-5 in PVP2 than in PVP1 images, and the specificity of PVP2 (93.5%) was comparable with PVP1 (93.5%).

Nonalcoholic fatty liver disease, characterized by excessive accumulation of fat in the liver, is the most common chronic liver disease worldwide. The current standard for the detection of hepatic steatosis is liver biopsy; however, it is limited by invasiveness and sampling errors. Accordingly, MR spectroscopy and proton density fat fraction obtained with MRI have been accepted as non-invasive modalities for quantifying hepatic steatosis. Recently, various quantitative ultrasonography techniques have been developed and validated for the quantification of hepatic steatosis. These techniques measure various acoustic parameters, including attenuation coefficient, backscatter coefficient and speckle statistics, speed of sound, and shear wave elastography metrics. In this article, we introduce several representative quantitative ultrasonography techniques and their diagnostic value for the detection of hepatic steatosis.