Continuous Shear Wave Elastography for Liver Using Frame-to-Frame Equalization of Complex Amplitude.

This study addresses a crucial necessity in the field of noninvasive liver fibrosis diagnosis by introducing the concept of continuous shear wave elastography (C-SWE), utilizing an external vibration source and color Doppler imaging. However, an application of C-SWE to assess liver elasticity, a deep region within the human body, arises an issue of signal instability in the obtained data. To tackle this challenge, this work proposes a method involving the acquisition of multiple frames of datasets, which are subsequently compressed. Furthermore, the proposed frame-to-frame equalization method compensates discrepancies in the initial phase that might exist among multiple-frame datasets, thereby significantly enhancing signal stability. The experimental validation of this approach encompasses both phantom tests and in vivo experiments. In the phantom tests, the proposed technique is validated through a comparison with the established shear wave elastography (SWE) technique. The results demonstrate a remarkable agreement, with an error in shear wave velocity of less than 4.2%. Additionally, the efficacy of the proposed method is confirmed through in vivo tests. As a result, the stabilization of observed shear waves using the frame-to-frame equalization technique exhibits promising potential for accurately assessing human liver elasticity. These findings collectively underscore the viability of C-SWE as a potential diagnostic instrument for liver fibrosis.

Deep learning approach for discrimination of liver lesions using nine time-phase images of contrast-enhanced ultrasound.

PURPOSE: Contrast-enhanced ultrasound (CEUS) shows different enhancement patterns depending on the time after administration of the contrast agent. The aim of this study was to evaluate the diagnostic performance of liver nodule characterization using our proposed deep learning model with input of nine CEUS images. METHODS: A total of 181 liver lesions (48 benign, 78 hepatocellular carcinoma (HCC), and 55 non-HCC malignant) were included in this prospective study. CEUS were performed using the contrast agent Sonazoid, and in addition to B-mode images before injection, image clips were stored every minute up to 10 min. A deep learning model was developed by arranging three ResNet50 transfer learning models in parallel. This proposed model allowed inputting up to nine datasets of different phases of CEUS and performing image augmentation of nine images synchronously. Using the results, the correct prediction rate, sensitivity, and specificity between "benign" and "malignant" cases were analyzed for each combination of the time phase. These accuracy values were also compared with the washout score judged by a human. RESULTS: The proposed model showed performance superior to the referential standard model when the dataset from B-mode to the 10-min images were used (sensitivity: 93.2%, specificity: 65.3%, average correct answer rate: 60.1%). It also maintained 90.2% sensitivity and 61.2% specificity even when the dataset was limited to 2 min after injection, and this accuracy was equivalent to or better than human scoring by experts. CONCLUSION: Our proposed model has the potential to identify tumor types earlier than the Kupffer phase, but at the same time, machine learning confirmed that Kupffer-phase Sonazoid images contain essential information for the classification of liver nodules.

Multivariable Quantitative US Parameters for Assessing Hepatic Steatosis.

Background Because of the global increase in the incidence of nonalcoholic fatty liver disease, the development of noninvasive, widely available, and highly accurate methods for assessing hepatic steatosis is necessary. Purpose To evaluate the performance of models with different combinations of quantitative US parameters for their ability to predict at least 5% steatosis in patients with chronic liver disease (CLD) as defined using MRI proton density fat fraction (PDFF). Materials and Methods Patients with CLD were enrolled in this prospective multicenter study between February 2020 and April 2021. Integrated backscatter coefficient (IBSC), signal-to-noise ratio (SNR), and US-guided attenuation parameter (UGAP) were measured in all participants. Participant MRI PDFF value was used to define at least 5% steatosis. Four models based on different combinations of US parameters were created: model 1 (UGAP alone), model 2 (UGAP with IBSC), model 3 (UGAP with SNR), and model 4 (UGAP with IBSC and SNR). Diagnostic performance of all models was assessed using area under the receiver operating characteristic curve (AUC). The model was internally validated using 1000 bootstrap samples. Results A total of 582 participants were included in this study (median age, 64 years; IQR, 52-72 years; 274 female participants). There were 364 participants in the steatosis group and 218 in the nonsteatosis group. The AUC values for steatosis diagnosis in models 1-4 were 0.92, 0.93, 0.95, and 0.96, respectively. The C-indexes of models adjusted by the bootstrap method were 0.92, 0.93, 0.95, and 0.96, respectively. Compared with other models, models 3 and 4 demonstrated improved discrimination of at least 5% steatosis (P < .01). Conclusion A model built using the quantitative US parameters UGAP, IBSC, and SNR could accurately discriminate at least 5% steatosis in patients with CLD. © RSNA, 2023 Supplemental material is available for this article. See also the editorial by Han in this issue.

Modified CEUS LI-RADS using Sonazoid for the diagnosis of hepatocellular carcinoma.

This review outlines several modified versions of the contrast-enhanced ultrasonography Liver Imaging Reporting and Data System (CEUS LI-RADS) that utilize Sonazoid. Furthermore, it discusses the advantages and challenges of diagnosing hepatocellular carcinoma using these guidelines, as well as the authors' expectations and opinions regarding the next CEUS LI-RADS version. It is possible that Sonazoid could be incorporated into the next version of CEUS LI-RADS.

The effect of attenuation inside the acoustic traps on the configuration of vertical artifacts in lung ultrasound: an experimental study with simple models.

PURPOSE: Using simple experimental models for lung ultrasound, we evaluated the relationship of the attenuation inside the sources of vertical artifacts to the echo intensity and attenuation of artifacts. METHODS: As sources of artifacts, we made 10 different hemispherical gel objects with two different mediums (pure agar or agar containing graphite with an attenuation coefficient of 0.5 dB/cm · MHz) and five different diameters (3.6, 5.6, 7.5, 9.5, or 11.4 mm). Ten of each hemispherical gel object were prepared for the statistical analyses. Each object was placed onto a chest wall phantom as the plane of the hemisphere was placed in an upward position. The echo intensity and attenuation of the artifact generated from each object was measured and compared. RESULTS: For all sizes, the intensity and attenuation of the artifacts in the objects made of agar containing graphite were significantly lower and larger, respectively, than those in the objects made of pure agar. In the objects containing graphite, the intensity decreased when the frequency was changed from 5 to 9 MHz. CONCLUSION: Based on this experiment, assessing the intensity and attenuation of vertical artifacts may help estimate the physical composition of sources of vertical artifacts in lung ultrasound.

Comparison of modified CEUS LI-RADS with sonazoid and CT/MRI LI-RADS for diagnosis of hepatocellular carcinoma.

AIM: 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. METHODS: 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. RESULTS: 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. CONCLUSIONS: 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.

Attenuation Coefficient Measurement Using a High-Frequency (2-9 MHz) Convex Transducer for Children Including Fatty Liver.

We evaluated the measurement feasibility and diagnostic ability of an ultrasound-guided attenuation parameter (UGAP) using a high-frequency convex transducer in children. This retrospective study included all consecutive children who underwent abdomen ultrasonography from July to December 2020. Attenuation coefficients (ACs) of the liver were measured using both 1- to 6-MHz (AC1-6) and 2- to 9-MHz (AC2-9) probes of the LOGIQ E10 system (GE Healthcare). t-Tests and Pearson's or partial correlation analyses were performed, and AC cutoff values for diagnosing fatty liver were obtained from receiver operating characteristic curve analyses. Finally, 118 patients (M:F = 83:35, mean age: 10.2 ± 4.1 y) were evaluated, and the measurement success rate was 98.3% (116/118) for AC2-9. AC1-6 was available in children with a liver depth greater than 9 cm. The ratio of interquartile range to median of the AC2-9 was lower than that of the AC1-6 (4.3 vs. 8.5, p < 0.001). In the normal group (n = 41), the AC2-9 values were not associated with age, sex or body mass index. For the evaluation of steatosis, the AC2-9 values exhibited a positive correlation with the MR fat fraction (coefficient = 0.498, p < 0.001). The cutoff value of 0.699 dB/cm/MHz had 90.2% sensitivity and 100% specificity for diagnosing fatty liver. In conclusion, measurements of ACs using a high-frequency convex transducer are feasible even in small children, with lower measurement variability. The AC2-9 values also had good diagnostic performance for pediatric fatty liver.

The Mechanisms Underlying Vertical Artifacts in Lung Ultrasound and Their Proper Utilization for the Evaluation of Cardiogenic Pulmonary Edema.

The recent advances in lung ultrasound for the diagnosis of cardiogenic pulmonary edema are outstanding; however, the mechanism of vertical artifacts known as B-lines used for the diagnosis has not yet been fully elucidated. The theory of "acoustic trap" is useful when considering the generation of vertical artifacts. Basic research in several studies supports the theory. Published studies with pilot experiments indicate that clarification of the relationship between the length and intensity of vertical artifacts and physical or acoustic composition of sources may be useful for differentiating cardiogenic pulmonary edema from lung diseases. There is no international consensus with regard to the optimal settings of ultrasound machines even though their contribution to the configuration of vertical artifacts is evident. In the clinical setting, the configuration is detrimentally affected by the use of spatial compound imaging, the placement of the focal point at a deep level, and the use of multiple focus. Simple educational materials using a glass microscope slide also show the non-negligible impact of the ultrasound machine settings on the morphology of vertical artifacts.

Noninvasive Diagnosis of Hepatocellular Carcinoma on Sonazoid-Enhanced US: Value of the Kupffer Phase.

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.

Simple Experimental Models for Elucidating the Mechanism Underlying Vertical Artifacts in Lung Ultrasound: Tools for Revisiting B-Lines.

Using simple experimental models, we evaluated the generation, configuration and echo intensity of vertical artifacts by varying the point or plane of contact and height of objects that correspond to sources of vertical artifacts in the subpleural space. We used an ultrasound gel spot to imitate the source and a block of bacon as a chest wall phantom. As the size of the point of contact between the gel spot on the polypropylene sheet and the phantom decreased by peeling the sheet, a vertical artifact measuring ≤1 cm was generated and/or extended deeper, finally reaching 10 cm in depth. Next, objects of different shapes made using gel balls were used to observe the generation of artifacts and measure and compare the echo intensity. For a given shape, the intensity was markedly higher in one model with the point of contact than in the other model with the plane of contact. With the same point or plane of contact, the echo intensity was higher in the taller model. The size of the point or plane of contact and height of the source were observed to be key factors in the generation, length and echo intensity of the artifacts.

Refraction artifact on abdominal sonogram.

Ultrasonography (US) is the first-line diagnostic tool for observing the whole abdomen. Unfortunately, a wide spectrum of refraction-related artefactual images is very frequently encountered in routine US examinations. In addition, most practitioners currently perform abdominal US examinations without sufficient knowledge of refraction artifacts (RAs). This review article was designed to present many representative RA images seen in the clinical setting, with a brief explanation of the mechanism of these images, in certain cases through an analyzed and reconstructed method using computer simulation that supports clinical observations. RAs are encountered not only with B-mode US but also with Doppler US, contrast-enhanced US, and shear wave elastography. RAs change their appearance according to the situation, but they always have a significant effect on detailed interpretation of abdominal US images. Correct diagnosis of abdominal US relies on a deep understanding of each characteristic artifactual finding, which necessitates knowledge of basic US physics. When analyzing mass lesions, computer simulation analysis helps to reveal the global images of RAs around a lesion.

Two-dimensional shear wave elastography and ultrasound-guided attenuation parameter for progressive non-alcoholic steatohepatitis.

BACKGROUND AND AIMS: We investigated the usefulness of combining two-dimensional shear wave elastography and the ultrasound-guided attenuation parameter for assessing the risk of progressive non-alcoholic steatohepatitis, defined as non-alcoholic steatohepatitis with a non-alcoholic fatty liver disease activity score of ≥4 and a fibrosis stage of ≥2. METHODS: This prospective study included 202 patients with non-alcoholic fatty liver disease who underwent two-dimensional shear wave elastography, ultrasound-guided attenuation parameter, vibration-controlled transient elastography, the controlled attenuation parameter, and liver biopsy on the same day. Patients were grouped according to liver stiffness measurement using two-dimensional shear wave elastography and the attenuation coefficient, assessed using the ultrasound-guided attenuation parameter: A, low liver stiffness measurement/low attenuation coefficient; B, low liver stiffness measurement/high attenuation coefficient; C, high liver stiffness measurement/low attenuation coefficient; and D, high liver stiffness measurement/high attenuation coefficient. RESULTS: Two-dimensional shear wave elastography and vibration-controlled transient elastography had equivalent diagnostic performance for fibrosis. The areas under the curve of the ultrasound-guided attenuation parameter for identifying steatosis grades ≥S1, ≥S2, and S3 were 0.89, 0.91, and 0.92, respectively, which were significantly better than those of the controlled attenuation parameter (P<0.05). The percentages of progressive non-alcoholic steatohepatitis in Groups A, B, C, and D were 0.0%, 7.7%, 35.7%, and 50.0%, respectively (P<0.001). The prediction model was established as logit (p) = 0.5414 × liver stiffness measurement (kPa) + 7.791 × attenuation coefficient (dB/cm/MHz)-8.401, with area under the receiver operating characteristic curve, sensitivity, and specificity values of 0.832, 80.9%, and 74.6%, respectively; there was no significant difference from the FibroScan-aspartate aminotransferase score. CONCLUSION: Combined assessment by two-dimensional shear wave elastography and the ultrasound-guided attenuation parameter is useful for risk stratification of progressive non-alcoholic steatohepatitis and may be convenient for evaluating the necessity of specialist referral and liver biopsy.

Liver stiffness does not affect ultrasound-guided attenuation coefficient measurement in the evaluation of hepatic steatosis.

AIM: Recently, a new method has been developed to diagnose hepatic steatosis with attenuation coefficients based on the ultrasound-guided attenuation parameter (UGAP). We investigated whether fibrosis identified by hepatic stiffness measurements based on magnetic resonance elastography (MRE) affects attenuation coefficient measurement using UGAP for the evaluation of hepatic steatosis. METHODS: A total of 608 patients with chronic liver disease were analyzed. Correlations between magnetic resonance imaging-determined proton density fat fraction (PDFF) or MRE value and attenuation coefficients were evaluated. In addition, the interaction between hepatic fibrosis and the attenuation coefficient was analyzed. RESULTS: The correlation coefficient (r) between PDFF values and attenuation coefficient values was 0.724, indicating a strong relationship. Conversely, the r between MRE values and attenuation coefficient values was -0.187, indicating almost no relationship. In the multiple regression assessment of the effect of PDFF and MRE on the attenuation coefficient based on UGAP, the P-values for PDFF, MRE, and PDFF × MRE were < 0.001, 0.277, and 0.903, respectively. In patients with non-alcoholic fatty liver disease (n = 169), the r between PDFF values and attenuation coefficient values was 0.695, indicating a moderate relationship. Conversely, the r between MRE values and attenuation coefficient values was -0.068, indicating almost no relationship. In the multiple regression assessment of the effect of PDFF and MRE on the attenuation coefficient based on UGAP, the P-values for PDFF, MRE, and PDFF × MRE were <0.001, 0.948, and 0.706, respectively. CONCLUSION: UGAP-determined attenuation coefficient was weakly affected by liver stiffness, an indicator of hepatic fibrosis.

A New Method to Quantify Concentration of Microbubbles in Attenuating Media Using Bubble Destruction Curve Analysis of the Contrast-Enhanced Ultrasound.

It is known that the microbubbles of Sonazoid are accumulated in the liver parenchyma due to the phagocytosis of Kupffer cells in the sinusoid. Because this phagocytic function decreases due to the progression of fibrosis in chronic liver disease, the deterioration of the liver function may be quantified by measuring the concentration of the accumulated Sonazoid microbubbles. In this article, a new method to quantify the concentration of microbubbles accumulated in attenuating media is proposed. This method utilizes the contrast-enhanced imaging with high mechanical index, measures the depth of the bubble destruction for each frame and analyze the shape of the destruction curve to estimate the concentration of the bubbles. A phantom experiment was performed with various concentrations of the contrast agent Sonazoid solution as well as various attenuation coefficients of the viscous media. Because of the theoretical model proposed, the estimated attenuation indexes, related to the concentration of Sonazoid microbubbles, were independent of the background attenuation of the propagating medium. The result suggest it has a potential to quantify Sonazoid concentration in the liver parenchyma more precisely against different liver attenuation conditions.

Ultrasonic B-Line-Like Artifacts Generated with Simple Experimental Models Provide Clues to Solve Key Issues in B-Lines.

We evaluated the influence of settings on an ultrasound machine on the configuration of a single B-line in a healthy model and analyzed the frequency spectrum. We also devised simple experimental models that generated B-line-like artifacts and evaluated the influence of the machine settings on the configuration. Visualization of B-lines was affected by the spatial compound imaging, the focal zone and the frequency. The spectra of both the B-line and non-B-line region at the same depth had the same center frequency and bandwidth. B-line-like artifact was generated by a spindle-shaped juice sac of a mandarin orange, an edible string-shaped glucomannan gel, glass beads and glass plates. Visualization of B-line-like artifacts was also affected by these machine settings. Our study indicated that the physical basis of some B-lines is multiple reverberations. B-line-like artifacts provide clues for solving key issues, such as the physical basis of B-lines, the sonographic-pathologic correlation in B-lines and the effects of machine settings.

Utility of Attenuation Coefficient Measurement Using an Ultrasound-Guided Attenuation Parameter for Evaluation of Hepatic Steatosis: Comparison With MRI-Determined Proton Density Fat Fraction.

OBJECTIVE: Recently, a new method was developed to diagnose hepatic steatosis by measuring attenuation coefficients that are based on the ultrasound-guided attenuation parameter (UGAP). We investigated the diagnostic ability of these coefficients to detect steatosis that was identified using the proton density fat fraction (PDFF) on MRI in patients with chronic liver disease. MATERIALS AND METHODS: A total of 126 patients with chronic liver disease (non-hepatitis B, non-hepatitis C) were analyzed. The diagnostic ability of UGAP-determined attenuation coefficients was evaluated using ROC curve analysis, and the correlation between MRI-determined PDFF values and attenuation coefficient values was determined. RESULTS: The correlation coefficient (r) between PDFF values and attenuation coefficient values was 0.746 (95% CI, 0.657-0.815) (p < 0.001), corresponding to a strong relationship. The diagnostic ability of attenuation coefficients for steatosis grades ≥ 1, ≥ 2, and 3 as determined by PDFF were 0.922 (95% CI, 0.870-0.973), 0.874 (95% CI, 0.814-0.934), and 0.892 (95% CI, 0.835-0.949), respectively. The r between PDFF values and attenuation coefficient values was 0.559 (95% CI, 0.391-0.705) (p < 0.001) in patients with mild or no steatosis (grade ≤ 1). In addition, the r between PDFF values and attenuation coefficient values was 0.773 (95% CI, 0.657-0.853) (p < 0.001) in obese patients (body mass index [weight in kilograms divided by the square of height in meters] ≥ 25). The diagnostic ability of attenuation coefficients for patients with steatosis grades ≥ 1, ≥ 2, and 3 as determined by PDFF were 0.884 (95% CI, 0.792-0.976), 0.863 (95% CI, 0.778-0.947), and 0.889 (95% CI, 0.813-0.965), respectively. CONCLUSION: UGAP-determined attenuation coefficient values had a good diagnostic ability to detect hepatic steatosis.

The B-Mode Image-Guided Ultrasound Attenuation Parameter Accurately Detects Hepatic Steatosis in Chronic Liver Disease.

The purpose of our study was to evaluate the diagnostic accuracy of the ultrasound-guided attenuation parameter (UGAP) for the detection of hepatic steatosis in comparison with the controlled attenuation parameter (CAP), using histopathology as the reference standard. We prospectively analyzed 163 consecutive chronic liver disease patients who underwent UGAP, CAP, computed tomography and a liver biopsy on the same day between April 2016 and July 2017. Radiofrequency signals corresponding to the images were compensated by the reference signal previously measured from the uniform phantom with known attenuation (0.44 dB/cm/MHz). The attenuation coefficient was calculated from the signals' decay slope. The median attenuation coefficient values in patients with S0 (n = 62), S1 (n = 63), S2 (n = 23) and S3 grade (n = 15) were 0.485, 0.560, 0.660 and 0.720, respectively. Significant correlations were found between attenuation coefficient and percentage steatosis, CAP values and liver-to-spleen computed tomography attenuation ratio (p < 0.001). The areas under the receiver operating characteristic curve of UGAP for identifying ≥S1, ≥S2 and ≥S3 were 0.900, 0.953 and 0.959, respectively, which were significantly better than the results obtained with CAP for identifying ≥S2 and ≥S3. In conclusion, UGAP had high diagnostic accuracy for detecting hepatic steatosis in patients with chronic liver disease.

Accuracy of 2D shear wave elastography in the diagnosis of liver fibrosis in patients with chronic hepatitis C.

PURPOSE: This prospective study was conducted to assess the diagnostic accuracy of two-dimensional shear wave elastography (2D SWE) in the diagnosis of liver fibrosis in patients with chronic liver disease and hepatitis C virus (HCV) compared with the serum liver fibrosis biomarkers using the results of liver biopsy as the reference standard. METHODS: We analyzed 233 consecutive HCV patients. On the same day, 2D SWE m, biochemical tests, and liver biopsy were performed. We used the METAVIR staging system and receiver operating characteristic curves for the analysis. RESULTS: The success rate of 2D-SWE was 98.7%. The median shear wave velocities (SWVs) of patients in the F0, F1, F2, F3, and F4 stages were 1.35 m/s, 1.42 m/s, 1.58 m/s, 1.83 m/s, and 2.13 m/s, respectively, demonstrating a stepwise increase (P < .0001). The accuracy of 2D-SWE in the prediction of ≥F1, ≥F2, ≥F3, and F4 was .888 (95% CI: .85-.93), .915 (95% CI: .88-095), .940 (95% CI: .91-.97), and .949 (95% CI: .92-.97), respectively. 2D-SWE was significantly superior to serum liver fibrosis biomarkers. CONCLUSION: 2D-SWE was positively correlated with the severity of liver fibrosis and was more useful for to predict all liver fibrosis grades in HCV patients than liver fibrosis biomarkers.

Effect of obstructive jaundice on hepatic hemodynamics: use of Sonazoid-enhanced ultrasonography in a prospective study of the blood flow balance between the hepatic portal vein and hepatic artery.

PURPOSE: To prospectively clarify the effects of obstructive jaundice (OJ) on hepatic hemodynamics using contrast-enhanced ultrasonography (US). METHODS: Subjects comprised 14 patients admitted to our hospital for OJ between April 2013 and March 2014. Contrast-enhanced US was performed using the LOGIQ E9 ultrasound device during the jaundice phase, before biliary drainage, and again after improvement of jaundice. After injecting the Sonazoid contrast agent, contrast dynamics were recorded in the right kidney and liver segments 5 or 6. Prototype software was used to calculate mean arrival time (AT) of the contrast agent in the liver parenchyma. Statistical analysis was performed to compare the mean AT in the jaundice and improved jaundice phases. RESULTS: We were unable to follow up three of the 14 patients after biliary drainage; thus, we included 11 patients for further analysis. The mean AT of the contrast agent was 2.0 ± 1.8 and 6.1 ± 2.3 s in the jaundice and improved jaundice phases, respectively, showing significantly shorter AT in the jaundice phase (p = 0.0033). CONCLUSION: Our findings indicate that OJ may influence the blood flow balance between the hepatic portal vein and hepatic artery.