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Shear wave elastography (SWE) is a clinical method used to evaluate liver hardness. In this study, we assessed its applicability in assessing the pancreas and its potential for diagnosing chronic pancreatitis.We performed SWE on 59 patients who underwent abdominal ultrasound, and measured the computed tomography (CT) values of the pancreas. Patients were classified as having a normal pancreas (NP), early chronic pancreatitis (ECP), or chronic pancreatitis (CP). SW elasticity (SWe), SW dispersion (SWd), and CT values between groups were analyzed.SWe significantly differed between the CP and NP/ECP groups (NP vs CP; P = 0.001, ECP vs CP; P = 0.026,), while SWd showed a significant difference only between the NP and CP group (NP vs CP; P = 0.001). The CT values were significantly different between the CP and NP/ECP groups (NP vs CP; P = 0.0006, ECP vs CP; P = 0.0027).Pancreatic SWE and CT values were helpful in the diagnosis of chronic pancreatitis. SWd may reveal status changes in ECP.

To compare the diagnostic performance based on the modified CEUS Liver Imaging Reporting and Data System (LI-RADS), which includes Kupffer-phase findings as a major imaging feature, with that of CT and MRI (CT/MRI) LI-RADS for liver nodules in patients at high risk of HCC.A total of 120 patients with 120 nodules were included in this retrospective study. The median size of the lesions was 20.0 mm (interquartile range, 14.0-30.8 mm). Of these lesions, 90.0% (108 of 120) were confirmed as HCCs, 6.7% (8 of 120) were intrahepatic cholangiocarcinomas, 1.7% (2 of 120) were metastases, and 1.7% (2 of 120) were dysplastic nodules. All nodules were diagnosed histopathologically. Each nodule was categorized according to the modified CEUS LI-RADS and CT/MRI LI-RADS version 2018. The diagnostic performance and inter-modality agreement of each criterion was compared.The inter-modality agreement for the modified CEUS LI-RADS and CT/MRI LI-RADS was slight agreement (kappa = 0.139, p = 0.015). The diagnostic accuracies of HCCs for the modified CEUS LR-5 and CT/MRI LR-5 were 70.0% (95% confidence interval [CI]: 61.0%, 78.0%) versus 70.8% (95% CI: 61.8%, 78.8%) (p = 0.876), respectively. The diagnostic accuracies of non-HCC malignancies for the modified CEUS LR-M and CT/MRI LR-M were 84.2% (95% CI: 76.4%, 90.2%) versus 96.7% (95% CI: 91.7%, 99.1%) (p = 0.002), respectively.The diagnostic performance for HCCs on the modified CEUS LR-5 and CT/MRI LR-5 are comparable. In contrast, CT/MRI LR-M has better diagnostic performance for non-HCC malignancy than that of the modified CEUS LR-M.

Background/aim We aimed to investigate the prognosis of patients who received radiofrequency ablation (RFA) for liver metastases of unresectable colorectal cancer (CRC). Patients and methods We retrospectively compared 147 patients treated for CRC liver metastases, who underwent RFA (n=26), resection (n=92), and chemotherapy (n=29) between 2001 and 2021. Results RFA and chemotherapy were performed for unresectable or non-operable cases, and resection was performed for suitable cases. The median overall survival (OS) was 44.9, 49.5, and 11.6 months for patients who underwent RFA, resection, and chemotherapy, respectively. RFA led to a significantly shorter OS compared to resection (p=0.027) but to a longer OS compared to chemotherapy (p=0.003). The 5-year survival rates were 34.6% and 42.4% for patients who underwent RFA and resection, respectively (p=0.508). Conclusion RFA has the potential to achieve long-term survival or radical cure, even for unresectable or non-operable cases of CRC with liver metastasis.

Background Nonalcoholic steatohepatitis (NASH) is diagnosed with histopathologic testing, but noninvasive surrogate markers are desirable for screening patients who are at high risk of NASH. Purpose To investigate the diagnostic performance of dispersion slope, attenuation coefficient, and shear-wave speed measurements obtained using two-dimensional (2D) shear-wave elastography (SWE) in assessing inflammation, steatosis, and fibrosis and in the noninvasive diagnosis of NASH in patients suspected of having nonalcoholic fatty liver disease (NAFLD). Materials and Methods This prospective study collected data from 120 consecutive adults who underwent liver biopsy for suspected NAFLD and were enrolled between April 2017 and March 2019. Three US parameters (dispersion slope [(m/sec)/kHz], attenuation coefficient [dB/cm/MHz], and shear-wave speed [in meters per second]) were measured using a 2D SWE system immediately before biopsy. The biopsy specimens were scored by one expert pathologist according to the Nonalcoholic Steatohepatitis Clinical Research Network criteria (119 participants underwent a histologic examination). Diagnostic performance was assessed using the area under the receiver operating characteristic curve (AUC) for the categories of inflammation, steatosis, and fibrosis. Results One hundred eleven adults (mean age, 53 years ± 18 [standard deviation]; 57 men) underwent a US examination. Dispersion slope enabled the identification of lobular inflammation, with an AUC of 0.95 (95% confidence interval [CI]: 0.91, 0.10) for an inflammation grade greater than or equal to A1 (mild), 0.81 (95% CI: 0.72, 0.89) for an inflammation grade greater than or equal to A2 (moderate), and 0.85 (95% CI: 0.74, 0.97) for an inflammation grade equal to A3 (marked). Attenuation coefficient enabled the identification of steatosis, with an AUC of 0.88 (95% CI: 0.80, 0.97) for steatosis grade greater than or equal to S1 (mild), 0.86 (95% CI: 0.79, 0.93) for steatosis grade greater than or equal to S2 (moderate), and 0.79 (95% CI: 0.68, 0.89) for steatosis grade equal to S3 (severe). Shear-wave speed enabled the identification of fibrosis, with an AUC of 0.79 (95% CI: 0.69, 0.88) for fibrosis stage greater than or equal to F1 (portal fibrosis), 0.88 (95% CI: 0.82, 0.94) for fibrosis stage greater than or equal to F2 (periportal fibrosis), 0.90 (95% CI: 0.84, 0.96) for fibrosis stage greater than or equal to F3 (septal fibrosis), and 0.95 (95% CI: 0.91, 0.99) for fibrosis stage equal to F4 (cirrhosis). The combination of dispersion slope, attenuation coefficient, and shear-wave speed showed an AUC of 0.81 (95% CI: 0.71, 0.91) for the diagnosis of NASH. Conclusion Dispersion slope, attenuation coefficient, and shear-wave speed were found to be useful for assessing lobular inflammation, steatosis, and fibrosis, respectively, in participants with biopsy-proven nonalcoholic fatty liver disease. © RSNA, 2020

The first edition of the guidelines for the use of ultrasound contrast agents was published in 2004, dealing with liver applications. The second edition of the guidelines in 2008 reflected changes in the available contrast agents and updated the guidelines for the liver, as well as implementing some nonliver applications. The third edition of the contrast-enhanced ultrasound (CEUS) guidelines was the joint World Federation for Ultrasound in Medicine and Biology-European Federation of Societies for Ultrasound in Medicine and Biology (WFUMB-EFSUMB) venture in conjunction with other regional US societies such as Asian Federation of Societies for Ultrasound in Medicine and Biology, resulting in a simultaneous duplicate on liver CEUS in the official journals of both WFUMB and EFSUMB in 2013. However, no guidelines were described mainly for Sonazoid due to limited clinical experience only in Japan and Korea. The new proposed consensus statements and recommendations provide general advice on the use of Sonazoid and are intended to create standard protocols for the use and administration of Sonazoid in hepatic and pancreatobiliary applications in Asian patients and to improve patient management.

Irreversible electroporation (IRE) is a novel form of soft tissue ablation therapy that uses high-current electrical pulses to induce the formation of pores in the cell membrane, leading to cell death. Although outcome data for the ablation of hepatocellular carcinoma (HCC) by IRE are limited, early results are encouraging and may suggest equivalency to the outcomes achieved by thermal ablation methods such as radiofrequency ablation (RFA) and microwave ablation (MWA). However, IRE can be a challenging and very time-consuming procedure compared to RFA and MWA. In this review article, we not only evaluate the efficacy and safety of IRE for the treatment of HCC, but also discuss imaging guidance, ablation monitoring, and endpoint assessment, with a particular focus on ultrasonography.

The detection and characterization of liver lesions are problematic in patients with bronchial asthma, renal dysfunction, or a history of allergy to gadolinium-based magnetic resonance contrast media or iodine-computed tomography contrast media because these contrast media cannot be used. Hence, the information on the lesion vascularity cannot be obtained. Therefore, this retrospective case-control study evaluated the feasibility of superparamagnetic iron oxide (SPIO) in patients with one or more of these contraindications who underwent SPIO-enhanced magnetic resonance imaging for the assessment of liver lesions.Twenty-six patients with a total of 48 lesions were analyzed. SPIO was used in the case of all patients because each patient had at least one reason not to use iodine contrast or gadolinium-based contrast media. Additionally, all patients were subjected to the perfusion study. A total volume of 1.3 mL of SPIO was injected via the cubital vein at a rate of 3 mL per second, followed by 40 mL saline at the same speed. The scanning of the perfusion study was started 4 s after the beginning of superparamagnetic iron oxide injection and scanning took 50 s. Two radiologists independently evaluated whether the lesion was malignant or benign. Receiver operating characteristic analysis (ROC) was performed to determine the additional benefit of the perfusion study.There were no adverse effects associated with SPIO. The area under the curve (AUC) value without perfusion study for observers 1 and 2 were 0.473 (P=0.794, 95% CI: 0.275-0.672) and 0.602 (P=0.305, 95% CI: 0.407-0.798), respectively, whereas the Az values with perfusion study for observers 1 and 2 were 0.782 (P=0.011, 95% CI: 0.565-0.998) and 0.784 (P=0.004, 95% CI: 0.591-0.977), respectively. Az value became significantly better when the perfusion study has added (P=0.001 and 0.012 by observers 1 and 2).SPIO can be used safely in patients with bronchial asthma, renal dysfunction, or a history of contrast media allergy. Furthermore, the diagnostic accuracy of SPIO was acceptable.

Yamamoto et al. report a case of intraductal residual lesions after endoscopic papillectomy successfully treated with endoscopic radiofrequency ablation therapy. This report provides readers with images and videos of precise intraductal radiofrequency ablation therapy methods for safe and effective eradication of intraductal residual lesions.

Background: Despite the diversity of thermal ablations, such as radiofrequency ablation (RFA) and microwave ablation (MWA), and non-thermal ablation, such as irreversible electroporation (IRE) cross-comparisons of multiple ablative modalities for hepatocellular carcinoma (HCC) treatment remain scarce. Thus, we investigated the therapeutic outcomes of different three ablation modalities in the treatment of early stage HCC. Methods: A total of 322 consecutive patients with 366 HCCs (mean tumor size ± standard deviation: 1.7 ± 0.9 cm) who underwent RFA (n = 216, 59.0%), MWA (n = 91, 28.3%), or IRE (n = 15, 4.7%) were included. Local tumor progression (LTP) rates for LTP were compared among the three modalities. Propensity score-matched analysis was used to reduce selection bias. Results: A significant difference in 2-year LTP rates between the IRE and RFA groups (IRE, 0.0% vs. RFA, 45.0%; p = 0.005) was found. There was no significant difference in 2-year LTP rates between the IRE and MWA groups (IRE, 0.0% vs. MWA, 25.0%; p = 0.103) as well as between the RFA and MWA groups (RFA, 18.2% vs. MWA, 20.6%; p = 0.586). Conclusion: IRE provides better local tumor control than RFA as a first-line therapeutic option for small perivascular HCC.

A 67-year-old man with a history of esophageal and gastric varices that were treated endoscopically was treated for Budd-Chiari syndrome and immunoglobulin G4-related sclerosing cholangitis in our facility. Varices in the second portion of the duodenum were revealed in follow-up upper endoscopy. The draining vein formed a venous plexus that was detected on computed tomography. Treatment with interventional radiology was difficult;therefore, endoscopic injection sclerotherapy (EIS) was performed instead. No recurrence has been observed to date. Thus, in this case, EIS for duodenal varices was effective.

The aim of this study was to compare the diagnostic performance of Contrast-Enhanced US Liver Imaging Reporting and Data System (CEUS LI-RADS) version 2017, which includes portal- and late-phase washout as a major imaging feature, with that of modified CEUS LI-RADS, which includes Kupffer-phase findings as a major imaging feature. Participants at risk of hepatocellular carcinoma (HCC) with treatment-naïve hepatic lesions (≥1 cm) were recruited and underwent Sonazoid-enhanced US. Arterial phase hyperenhancement (APHE), washout time, and echogenicity in the Kupffer phase were evaluated using both criteria. The diagnostic performance of both criteria was analyzed using the McNemar test. The evaluation was performed on 102 participants with 102 lesions (HCCs (n = 52), non-HCC malignancies (n = 36), and benign (n = 14)). Among 52 HCCs, non-rim APHE was observed in 92.3% (48 of 52). By 5 min, 73.1% (38 of 52) of HCCs showed mild washout, while by 10 min or in the Kupffer phase, 90.4% (47 of 52) of HCCs showed hypoenhancement. The sensitivity (67.3%; 35 of 52; 95% CI: 52.9%, 79.7%) of modified CEUS LI-RADS criteria was higher than that of CEUS LI-RADS criteria (51.9%; 27 of 52; 95% CI: 37.6%, 66.0%) (p = 0.0047). In conclusion, non-rim APHE with hypoenhancement in the Kupffer phase on Sonazoid-enhanced US is a feasible criterion for diagnosing HCC.

Background Nonalcoholic fatty liver disease (NAFLD) is common in the general population but identifying patients with high-risk nonalcoholic steatohepatitis (NASH) who are candidates for pharmacologic therapy remains a challenge. Purpose To develop a score to identify patients with high-risk NASH, defined as NASH with an NAFLD activity score (NAS) of 4 or greater and clinically significant fibrosis (stage 2 [F2] or higher). Materials and Methods This was a cross-sectional secondary analysis of data prospectively collected between April 2017 and March 2019 for a group of patients with NAFLD in Japan (Japan NAFLD, the derivation data set) with contemporaneous two-dimensional shear-wave elastography and biopsy-proven NAFLD (age range, 20-89 years). Three US markers (liver stiffness [LS, measured in kilopascals], attenuation coefficient [AC, measured in decibels per centimeter per megahertz], and dispersion slope [DS, measured in meters per second per kilohertz]) were determined, together with aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels and the AST-to-ALT ratio. The best-fit multivariate logistic regression model for identifying patients with high-risk NASH was determined. Diagnostic performance was assessed by using the area under the receiver operating characteristic curve (AUC). The findings were validated in an independent data set (Korea NAFLD; age range, 20-78 years). Results The Japan NAFLD data set included 111 patients (mean age, 53 years ± 18 [standard deviation]; 57 men), 84 (76%) with NASH. The Korea NAFLD data set included 102 patients (mean age, 48 years ± 18; 43 men), 55 (36%) with NASH. The most predictive model (LAD NASH score) combined LS, AC, and DS. Performance was satisfactory in both the derivation sample (AUC, 0.86; 95% CI: 0.79, 0.93) and the validation sample (AUC, 0.88; 95% CI: 0.80, 0.95). The LAD NASH score showed a positive predictive value of 86.5% and a negative predictive value of 87.5% for high-risk NASH in the derivation sample. Conclusion A score combining three US markers may be useful for noninvasive identification of patients with high-risk nonalcoholic steatohepatitis for inclusion in clinical trials and pharmacologic therapy. © RSNA, 2021 Online supplemental material is available for this article. See also the editorial by Lockhart in this issue.

Ultrasound-guided attenuation parameter (UGAP) is recently developed for noninvasive evaluation of steatosis. However, reports on its usefulness in clinical practice are limited. This prospective multicenter study analyzed the diagnostic accuracy of grading steatosis with reference to magnetic resonance imaging-based proton density fat fraction (MRI-PDFF), a noninvasive method with high accuracy, in a large cohort.Altogether, 1010 patients with chronic liver disease who underwent MRI-PDFF and UGAP were recruited and prospectively enrolled from 6 Japanese liver centers. Linearity was evaluated using intraclass correlation coefficients between MRI-PDFF and UGAP values. Bias, defined as the mean difference between MRI-PDFF and UGAP values, was assessed by Bland-Altman analysis. UGAP cutoffs for pairwise MRI-PDFF-based steatosis grade were determined using area under the receiver-operating characteristic curve (AUROC) analyses.UGAP values were shown to be normally distributed. However, because PDFF values were not normally distributed, they were log-transformed (MRI-logPDFF). UGAP values significantly correlated with MRI-logPDFF (intraclass correlation coefficient = 0.768). Additionally, Bland-Altman analysis showed good agreement between MRI-logPDFF and UGAP with a mean bias of 0.0002% and a narrow range of agreement (95% confidence interval [CI], -0.015 to 0.015). The AUROCs for distinguishing steatosis grade ≥1 (MRI-PDFF ≥5.2%), ≥2 (MRI-PDFF ≥11.3%), and 3 (MRI-PDFF ≥17.1%) were 0.910 (95% CI, 0.891-0.928), 0.912 (95% CI, 0.894-0.929), and 0.894 (95% CI, 0.873-0.916), respectively.UGAP has excellent diagnostic accuracy for grading steatosis with reference to MRI-PDFF. Additionally, UGAP has good linearity and negligible bias, suggesting that UGAP has excellent technical performance characteristics that can be widely used in clinical trials and patient care. (UMIN Clinical Trials Registry, Number: UMIN000041196).

Background & Aims: Direct-acting antiviral agents (DAAs) and the risk of hepatocellular carcinoma (HCC) is controversially reported in the literature. The primary endpoints of this study were to clarify the cumulative incidence and recurrence rate of HCC after DAA treatment. The secondary endpoints were to identify the factors associated with the occurrence or recurrence of HCC after DAAs treatment.Methods: Of 234 HCV patients, 211 with no history of HCC (no-HCC-history group) and 23 with previous treated HCC history (HCC-history group) were treated with DAAs and followed for more than 24 weeks to determine the incidence of HCC. Platelet count, albumin, α-fetoprotein (AFP) level, L3%, the FIB-4 index and APRI scores were analyzed as possible factors associated with HCC occurrence and recurrence. An intergroup comparison was made of the cumulative incidence of HCC. Cox proportional hazards regression was used to determine associations between blood test values and risk of HCC.Results: The median observation period was 21 months. Cumulative incidence of HCC was higher in the HCChistory group than in the no-HCC-history group (p < 0.0001, 19.0 and 0.52 per 100 patient-years, respectively). Univariate analysis revealed platelet count, albumin, α-fetoprotein (AFP) level, AFP-L3%, and FIB-4 index and APRI scores at the end of DAA treatment as being significantly associated with occurrence/recurrence of HCC. Multivariate analysis revealed that AFP levels before and after the administration of DAAs and AFP-L3% after DAA were independently associated with the occurrence/recurrence of HCC (p = 0.045, 0.043, 0.005, respectively).Conclusion: The HCC occurrence rate after DAA treatment was very low, and the recurrence rate lower than that in previous interferon reports. The AFP level and AFP-L3% were identified as important factors in predicting occurrence/recurrence of HCC. Careful observation is needed when increased levels of AFP or AFP-L3% after DAAs treatment are observed.

Measurement of spleen stiffness (SS) using ultrasound (US) elastography is useful for predicting portal hypertension. However, the mechanism leading to increased SS remains unclear. We jointly developed a new US elastography system (Aplio i-series, Canon Medical Systems) that can easily measure organ viscosity (dispersion slope: DS). We analyzed the cause of increased SS by calculating the shear wave speed (SWs, which reflects fibrosis) and DS of the spleen in carbon tetrachloride (CCL4) rat liver cirrhosis models. A total of 13 Sprague–Dawley rats were randomly divided into four groups (C group: 3 rats as control, 2D group: 3 rats injected with CCL4 twice in 1 week, 4D group: 4 rats injected 4 times in 1 week, 6W group: 3 rats injected twice a week for 6 weeks). The SWs and the DS of each group were calculated, and histopathological analysis was performed. The spleen SWs of the 6W group was significantly higher than that of the C group (p = 0.044). The spleen DS did not change after CCL4. The liver SWs of the 4D and 6W groups was significantly higher than that of the C group (p = 0.012 and 0.007, respectively) with fibrosis change on histopathology, and the DS of the 4D group was significantly higher than that of the C group (p = 0.033). Splenic fibrosis was confirmed in the 6W group, but inflammation and necrosis were not seen. SS increased due to fibrosis and can be predicted based on SWs and DS values.

Attenuation imaging (ATI) is a new noninvasive ultrasound technique for assessing steatosis grade (S). However, validated region-of-interest (ROI) sampling strategies are not currently available. We investigated the diagnostic performance of various ATI-ROI positions for determining histopathologic S in patients with nonalcoholic fatty liver disease (NAFLD). This retrospective study included 105 patients with biopsy-proven NAFLD. All attenuation coefficient (AC, dB/cm/MHz) measurements were obtained by the same hepatologist using a commercially available ultrasound system on the same day as liver biopsy. Mean (± standard deviation) age and body mass index of the patients were 53 (± 18) years and 27.1 (± 4.1) kg/m2, respectively. The numbers of patients with steatosis affecting 66% of hepatocytes were 8, 50, 29, and 18, respectively. The ATI-ROI was placed at three different positions for AC measurement using a dedicated workstation: the upper edge of the area ROI, twice the depth of the liver capsule, and the lower edge of the area ROI. Diagnostic performance was evaluated using the area under the receiver-operating characteristic curve (AUC). The AUCs of AC at the three ATI-ROI positions were 0.734 (95% confidence interval [CI]: 0.470–0.998), 0.750 (0.639–0.861), and 0.878 (0.788–0.968) for S ≥ 1; 0.503 (0.392–0.615), 0.824 (0.741–0.907), and 0.809 (0.724–0.895) for S ≥ 2; and 0.606 (0.486–0.726), 0.849 (0.767–0.932), and 0.737 (0.626–0.848) for S = 3, respectively. For accurate steatosis grade assessment, the ATI-ROI should not be placed at the upper edge of the area ROI.

Background: Ultrasound-guided attenuation parameter (UGAP) is a tool recently developed for noninvasive evaluation of hepatic steatosis. However, there are still few reports on its usefulness in clinical practice. This prospective multicenter study analyzed the diagnostic accuracy of grading hepatic steatosis with reference to magnetic resonance imaging-based proton density fat fraction (MRI-PDFF) in a large cohort of patients with chronic liver disease. Methods: A total of 1010 patients with chronic liver disease were prospectively enrolled from six Japanese liver centers. MRI-PDFF and UGAP values were analyzed to examine whether the distribution was normal using a normal probability plot. Linearity was evaluated using intra-class correlation coefficients (ICCs) between MRI-PDFF and UGAP values. Bias, defined as the mean difference between MRI-PDFF and UGAP values, was assessed by Bland–Altman analysis. UGAP cutoffs for pairwise MRI-PDFF-based hepatic steatosis grade were determined using area under the receiver operating characteristics curve (AUROC) analyses. Findings: UGAP values were shown to be normally distributed. In contrast, since PDFF values were not normally distributed, they were log-transformed (MRI-logPDFF). UGAP values were significantly correlated with MRI-logPDFF (ICC=0·768). Additionally, Bland–Altman analysis showed good agreement between MRI-logPDFF and UGAP with a mean bias of 0·0002% and a narrow range of agreement (95% CI: -0·015–0·015). The AUROCs for distinguishing ≥S1 (MRI-PDFF>5·2%), ≥S2 (MRI-PDFF>11·3%), and S3 (MRI-PDFF>17·1%) were 0·910 (95% CI: 0·891–0·928), 0·912 (95% CI: 0·894–0·929), and 0·894 (95% CI: 0·873–0·916), respectively. Clinical Trial: This study was registered in the UMIN Clinical Trials Registry (UMIN000041196). Interpretation: UGAP has an excellent diagnostic accuracy for grading hepatic steatosis with reference to MRI-PDFF. Additionally, UGAP has good linearity and negligible bias, suggesting that UGAP has excellent technical performance characteristics that can be widely used in clinical trials and patient care. Funding: GE Healthcare and JSPS KAKENHI [grant number JP 21K07987]. Declaration of Interest: Kento Imajo, Hidenori Toyoda, Satoshi Yasuda, Yasuaki Suzuki, Katsutoshi Sugimoto, Hidekatsu Kuroda, Tomoyuki Akita, Junko Tanaka, Yutaka Yasui, Masayuki Kurosaki, Namiki Izumi, Atsushi Nakajima, and Takashi Kumada have no competing interests to disclose. Ethical Approval: This study was approved by the Ogaki Municipal Hospital and by the local research ethics committee at each center.

New ultrasound methods that can be used to quantitatively assess liver fat content have recently been developed. These quantitative ultrasound (QUS) methods are based on the analysis of radiofrequency echoes detected by the transducer, allowing calculation of parameters for quantifying the fat in the liver. In this position paper, after a section dedicated to the importance of quantifying liver steatosis in patients with non-alcoholic fatty liver disease and another section dedicated to the assessment of liver fat with magnetic resonance, the current clinical studies performed using QUS are summarized. These new methods include spectral-based techniques and techniques based on envelope statistics. The spectral-based techniques that have been used in clinical studies are those estimating the attenuation coefficient and those estimating the backscatter coefficient. Clinical studies that have used tools based on the envelope statistics of the backscattered ultrasound are those performed by using the acoustic structure quantification or other parameters derived from it, such as the normalized local variance, and that performed by estimating the speed of sound. Experts' opinions are reported.

The Contrast-Enhanced Ultrasound Liver Imaging Reporting and Data System (CEUS LI-RADS) was introduced for classifying suspected hepatocellular carcinoma (HCC). However, it cannot be applied to Sonazoid. We assessed the diagnostic usefulness of a modified CEUS LI-RADS for HCC and non-HCC malignancies based on sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV). Patients with chronic liver disease at risk for HCC were evaluated retrospectively. Nodules ≥1 cm with arterial phase hyperenhancement, no early washout (within 60 s), and contrast defects in the Kupffer phase were classified as LR-5. Nodules showing early washout, contrast defects in the Kupffer phase, and/or rim enhancement were classified as LR-M. A total of 104 nodules in 104 patients (median age: 70.0 years; interquartile range: 54.5–78.0 years; 74 men) were evaluated. The 48 (46.2%) LR-5 lesions included 45 HCCs, 2 high-flow hemangiomas, and 1 adrenal rest tumor. The PPV of LR-5 for HCC was 93.8% (95% confidence interval (CI): 82.8–98.7%). The 22 (21.2%) LR-M lesions included 16 non-HCC malignancies and 6 HCCs. The PPV of LR-M for non-HCC malignancies, including six intrahepatic cholangiocarcinomas, was 100% (95% CI: 69.8–100%). In conclusion, in the modified CEUS LI-RADS for Sonazoid, LR-5 and LR-M are good predictors of HCC and non-HCC malignancies, respectively.

To investigate the usefulness of shear-wave speed and dispersion slope measurements obtained, using an ultrasound elastography system in rat livers with various degrees of necroinflammation and fibrosis. A total of 25 male Sprague Dawley rats were randomly divided into 5 groups of 5 rats each: G0 (control), G1 (CCl4 injected twice a week for 1 wk), G2 (CCl4 injected four times a wk for 1 wk), G3 (CCl4 injected twice a wk for 6 wk) and G4 (CCl4 injected twice a wk for 10 wk). The shear-wave speed (m/s) and the dispersion slope ([m/s]/kHz) were measured. Histologic features (inflammation, necrosis and fibrosis) were used as reference standards. In multivariable analysis with histologic features as independent variables, the fibrosis grade was significantly related to shear-wave speed (p < 0.05) and the necrosis grade was significantly related to dispersion slope (p < 0.05). Dispersion slope is more useful than shear-wave speed for predicting the degree of necroinflammation.

Hepatic adrenal rest include ectopic adrenal tissue in the liver and adrenohepatic fusion. Long-lasting hyperstimulation of that tissue induces hyperplasia sometimes simulating true tumors. True autonomic tumors originating from ectopic adrenal tissue with or without hyperfunction are rare. Hepatic adrenal rest sometimes has similar imaging findings to lipid-rich hepatocellular carcinoma or angiomyolipoma, containing obvious lipid component. But in our cases, tumors showed hypervascular patterns similar to hepatocellular adenoma or carcinoma. Therefore, adrenocortical scintigraphy with SPECT/CT should be taken into consideration to diagnose tumoral lesions in the posterior segment of the right hepatic lobe with or without an obvious lipid component.

AIM Interferon-free direct-acting antiviral (DAA) therapy is an effective treatment for chronic hepatitis C (CH(C)) patients. Activity of natural killer (NK) cells was reported to be impaired in patients with hepatitis C virus infection. The aim of this study was to examine whether DAA therapy could restore NK activity in patients with CH(C). METHODS Direct-acting antiviral therapy was given to 31 CH(C) patients as asunaprevir/daclatasvir (ASV/DCV) (n = 15), ledipasvir/sofosbuvir (n = 7), ombitasvir/paritaprevir/ritonavir (n = 6), or elbasvir/grazoprevir (n = 3). Prior to therapy (0M), at the completion of the therapy (EOT), and at 24 weeks after completion (AFTER), NK activity and the frequency of CD56dim NK and CD56bright NK cells in peripheral blood were estimated by Cr release assay and flow cytometry. Statistical analysis was carried out by anova and the Mann-Whitney U-test. RESULTS In one of the ASV/DCV-treated patients, treatment was stopped 12 weeks after initiation of therapy because of viral breakthrough. The anova showed that NK activity significantly improved at EOT (vs. 0M, P

A 27-year-old woman with colon cancer and liver metastasis was referred to our hospital. Colectomy and colostomy were performed to improve her ileus. Following 13 sessions of oxaliplatin-based chemotherapy (OC) with mFOLFOX6 + bevacizumab, thrombocytopenia and frequent peristomal bleeding occurred. Computed tomography showed severe ascites, splenomegaly, significant collateral veins around the stoma, and severe stenosis of the hepatic veins (HV) and inferior vena cava (IVC). Ultrasound elastography showed high liver (and spleen) stiffness values. Repeated OC appeared to cause IVC stenosis as a result of worsening sinusoidal obstruction syndrome (SOS), and peristomal variceal bleeding. After ultrasound-guided percutaneous embolization, bleeding did not recur. Unfortunately, the patient died of liver dysfunction caused by severe SOS. The incidence of OC-induced SOS is reported to be about 50%; however, there is apparently no report of OC-induced HV and IVC stenosis, and in most cases, portal hypertension is improved after OC cessation. This is the first report of OC-induced severe HV and IVC stenosis resulting in refractory peristomal variceal bleeding and eventual death.

Background Recently, diffusion-weighted imaging (DWI) and quantitative enhancement ratio measured at the hepatobiliary phase (HBP) of Gd-EOB-DTPA–enhanced magnetic resonance imaging (MRI) has been established as an effective method for evaluating liver fibrosis. Purpose To evaluate which is a more favorable surrogate marker in predicting high-stage liver fibrosis, apparently diffusion coefficient (ADC) value or quantitative enhancement ratio measured on HBP. Material and Methods Eighty-three patients with 99 surgically resected hepatic lesions were enrolled in this study. DWI was performed with b-values of 100 and 800 s/mm2. Regions of interest were set on ADC map, and the HBP of Gd-EOB-DTPA–enhanced MRI, to calculate ADC value, liver-to-muscle ratio (LMR), liver-to-spleen ratio (LSR), and contrast enhancement index (CEI) of liver. We compared these parameters between low-stage fibrosis (F0, F1, and F2) and high-stage fibrosis (F3 and F4). Receiver operating characteristic analysis was performed to compare the diagnostic performance when distinguishing low-stage fibrosis from high-stage fibrosis. Results LMR and CEI were significantly lower at high-stage fibrosis than at the low stage ( P Conclusion LMR and CEI were both adequate surrogate parameters to distinguish high-stage fibrosis from low-stage fibrosis.