Transient hepatic echogenicity difference on contrast-enhanced ultrasonography: sonographic sign and pitfall

Pyogenic liver abscess: contrast-enhanced ultrasound allows morpho-evolutive classification and guides personalized management

Aim: The aim of this study is to propose a contrast-enhanced ultrasound (CEUS)-based morphologic classification of pyogenic liver abscess (PLA) reflecting different evolutive stages and to assess the added value of CEUS in the management of PLA. Methods: Forty-four PLAs of different etiologies in 44 patients (male/female = 24/20; mean age 66 ± 14.7 years) were evaluated with ultrasound (US) B-mode and CEUS (using SonoVue). PLAs were mainly located in the right lobe (n = 28, 63.6%) with a mean diameter of 6.8 cm [standard deviation (SD) ± 3.2, range 1.7–15 cm]. Conventional US findings were categorized as the presence and extension of liquified areas, echogenicity and echostructure of the index lesion. Peripheral hyperenhancing rim, transient segmental enhancement, hyperenhancing septa and “honeycomb” aspect were considered PLA hallmarks in the arterial phase after contrast agent injection. CEUS results were judged as clinically relevant if they modified the approach to percutaneous treatment in comparison with pre-operative US B-mode findings. Results: CEUS was superior to US B-mode as to depiction of PLA internal echostructure and enabled identification of 4 evolutive stages of PLA: type I (tumor-like), type II (“honeycomb”), type III (multiloculated with incomplete septa), and type IV (cystic-like). In 22 cases (67.4%) out of 34 who underwent percutaneous treatment, the operator tailored percutaneous approach according to PLA internal echostructure observed during CEUS exam. Conclusions: CEUS depicts the internal structure of PLA so allowing a morpho-evolutive classification of PLA and provides invaluable information for immediately tailoring the management to the single case. By showing the structure of PLA more precisely, CEUS allows a morpho-evolutive PLA classification and guides tailored management in the single case.

Guidelines and Good Clinical Practice Recommendations for Contrast Enhanced Ultrasound (CEUS) in the Liver - Update 2020 - WFUMB in Cooperation with EFSUMB, AFSUMB, AIUM, and FLAUS

The present, updated document describes the fourth iteration of recommendations for the hepatic use of contrast enhanced ultrasound (CEUS), first initiated in 2004 by the European Federation of Societies for Ultrasound in Medicine and Biology (EFSUMB). The previous updated editions of the guidelines reflected changes in the available contrast agents and updated the guidelines not only for hepatic but also for non-hepatic applications.The 2012 guideline requires updating as previously the differences of the contrast agents were not precisely described and the differences in contrast phases as well as handling were not clearly indicated. In addition, more evidence has been published for all contrast agents. The update also reflects the most recent developments in contrast agents, including the United States Food and Drug Administration (FDA) approval as well as the extensive Asian experience, to produce a truly international perspective.These guidelines and recommendations provide general advice on the use of ultrasound contrast agents (UCA) and are intended to create standard protocols for the use and administration of UCA in liver applications on an international basis to improve the management of patients.

Added value of 2D shear wave imaging of the gallbladder bed of the liver for acute cholecystitis

PURPOSE

The purpose of this study was to evaluate whether shear wave elastography (SWE) and the shear wave dispersion slope (SWD) obtained from 2-dimensional shear wave imaging (2D-SWI) of the gallbladder (GB) bed of the liver could be helpful in the diagnosis of acute cholecystitis.

METHODS

We included 44 patients referred for abdominal ultrasonography (US) under the impression of acute cholecystitis from April 2018 to March 2019. Patients with chronic liver disease were excluded from this study. In addition to routine upper abdominal US, we performed 2D-SWI including liver stiffness measurements by SWE and SWD, which reflects tissue viscosity. 2D-SWI was performed at the GB bed of the liver through the right intercostal approach at least 3 times with different frames. We assessed typical US findings and the added value of 2D-SWI in diagnosing acute cholecystitis. Histopathologic results of surgical specimens were used as the standard of reference. If a surgical specimen was unavailable, a bile fluid test or clinical follow-up for more than 3 months served as the reference standard.

RESULTS

The optimal cutoff values for SWE and SWD were 8 kPa and 10.9 (m/sec)/kHz, respectively. In the univariate analysis, SWE, GB distension, and sludge were predictive factors of acute cholecystitis. In the multivariate analysis, categorized SWE was the only significant predictor (P<0.01). By using 2D-SWI, the diagnostic performance of two readers did not significantly increase, although the inter-reader agreement improved (k=0.654-0.778).

CONCLUSION

2D-SWI of the GB bed of the liver could be helpful for diagnosing acute cholecystitis.

Guidelines and Good Clinical Practice Recommendations for Contrast-Enhanced Ultrasound (CEUS) in the Liver-Update 2020 WFUMB in Cooperation with EFSUMB, AFSUMB, AIUM, and FLAUS

The present, updated document describes the fourth iteration of recommendations for the hepatic use of contrast-enhanced ultrasound, first initiated in 2004 by the European Federation of Societies for Ultrasound in Medicine and Biology. The previous updated editions of the guidelines reflected changes in the available contrast agents and updated the guidelines not only for hepatic but also for non-hepatic applications. The 2012 guideline requires updating as, previously, the differences in the contrast agents were not precisely described and the differences in contrast phases as well as handling were not clearly indicated. In addition, more evidence has been published for all contrast agents. The update also reflects the most recent developments in contrast agents, including U.S. Food and Drug Administration approval and the extensive Asian experience, to produce a truly international perspective. These guidelines and recommendations provide general advice on the use of ultrasound contrast agents (UCAs) and are intended to create standard protocols for the use and administration of UCAs in liver applications on an international basis to improve the management of patients.

The Efficacy of Sonazoid-enhanced Ultrasonography in Decision-making for Liver Abscess Treatment

Objective The usefulness of contrast-enhanced ultrasonography (CEUS) for making decisions in the treatment of liver abscess is unknown. Methods We evaluated the internal blood flow in the arterial-predominant phase by CEUS using Sonazoid^® in 21 patients. The stain area rate was evaluated in maximum parting plane of abscess in CEUS. Patients were divided into two groups: the vascular phase enhancement (VE) group, in which ≥50% of the abscess cavity was enhanced (12 patients), and the vascular phase non-enhancement (VNE) group, in which <50% of the abscess cavity was enhanced (9 patients). The rate of patients who were cured by conservative treatment alone was examined in both groups. The defect rate of all liver abscesses in the post-vascular phase was also evaluated. Results In the VE group, improvement by conservative treatment alone was obtained in 11 out of 12 patients (91.7%), while in the VNE group, improvement by conservative treatment alone was obtained in only 1 out of 9 patients (11.1%), a significant difference (p<0.001). In the VE group, one patient did not improve with conservative treatment alone because the abscess ruptured near the liver surface. In the VE group, the abscess size was smaller than in the VNE group. By examining the defect rate in the post-vascular phase, it was found that 16 out of 21 patients (76.2%) showed 71% or more defects. Conclusion The enhancement rate in the arterial-predominant phase of CEUS was considered useful for determining the treatment approach for liver abscess.

Contrast-Enhanced Ultrasound

Contrast-enhanced ultrasound imaging is a recently approved technique in the United States that uses a specific contrast agent, namely, microbubbles, consisting mainly of a gas core and a stabilized biological shell. These compounds allow for the visualization of small vascular beds and improve characterization of anatomic structures and lesions. They have a relatively safe profile and are primarily excreted through the lungs.

Ongoing challenges in the diagnosis of hepatocellular carcinoma

In 2001, the European Association for the Study of the Liver (EASL) endorsed the possibility of achieving a non-invasive diagnosis of Hepatocellular Carcinoma (HCC) for the first time. Since then, various refinements of the criteria and techniques capable of achieving this diagnosis and the role of plasma and tissue oncomarkers have been reported in the literature and have been accepted to different extents in various geographical areas. Such tools can also potentially imply prognostic significance. The present article critically discusses some of the most relevant and debated challenges which have emerged in this field, including the role of contrast-enhanced ultrasound, and of hepatocyte-specific magnetic resonance contrast agents, the pitfall of transient hepatic attenuation differences, the reliability of biopsy and the status of biomarkers.

Cancer Measurement at Ultrasound: State of the Art

Reliable and reproducible tumor measurement is fundamental in the oncologic decision making. In this article, we first highlight the importance of a precise tumor measurement, reviewing the correct modality of measuring tumor lesions at ultrasound. Then we analyze the measurement discrepancies between ultrasound and pathology as well as the discrepancies reported between ultrasound and other imaging modalities. Thereafter, basing on the existent literature and on our experience, we discuss the factors influencing the tumor size measurements at ultrasound. Finally, we illustrate the current strategies to improve the effectiveness of cancer lesions measurement.

3D versus 2D contrast-enhanced sonography in the evaluation of therapeutic response of hepatocellular carcinoma after locoregional therapies: preliminary findings

OBJECTIVE

To investigate diagnostic performance of 3D contrast-enhanced ultrasound (CEUS) compared with 2D CEUS in the assessment of therapeutic response of hepatocellular carcinoma (HCC) treated with locoregional therapies (LRT).

MATERIALS AND METHODS

Twenty-three consecutive patients (13 men and 10 women; mean age 65.5 years) with 23 HCCs (size range 1.2-7.2 cm; mean size 2.9 ± 1.4 cm) treated by means of radiofrequency ablation (RFA n = 9), transarterial chemoembolization (TACE n = 8), combined RFA and TACE (n = 3), percutaneous alcoholization (n = 2), and wedge resection (n = 1) underwent 2D and 3D CEUS 1 month (30 ± 2 days) after treatment. Magnetic resonance (n = 17) and computed tomography (n = 6) acted as standard of reference (SOR). Two radiologists assessed the absence (complete response CR) or presence (residual tumor RT) of any nodular arterially enhancing area within or along the margin of the treated HCC.

RESULTS

Both 2D and 3D CEUS observed CR in 10/23 (43.5 %) HCCs and RT in 11/23 (47.8 %) HCCs. In 1/23 (4.3 %) HCC, RT was documented by SOR and 2D CEUS, but it was not appreciable at 3D CEUS. In 1/23 (4.3 %) HCC, the presence of peripheral residual tumor was suspected by both 2D and 3D CEUS, but it was not confirmed by SOR. No statistically significant difference between 2D and 3D CEUS in depicting either CR or RT was found (p > 0.05). Sensitivity, specificity, positive and negative predictive values, and accuracy of 3D CEUS were 91.7 % [95 % confidence interval (CI) 0.760-1.073], 90.9 % (95 % CI 0.739-1.079), 91.7, 90.9, and 91.3 %, respectively.

CONCLUSION

2D and 3D CEUS provided similar diagnostic performance in the assessment of therapeutic response of HCC treated with LRT.

Guidelines and good clinical practice recommendations for Contrast Enhanced Ultrasound (CEUS) in the liver - update 2012: A WFUMB-EFSUMB initiative in cooperation with representatives of AFSUMB, AIUM, ASUM, FLAUS and ICUS

Initially, a set of guidelines for the use of ultrasound contrast agents was published in 2004 dealing only with liver applications. A 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 non-liver applications. Time has moved on, and the need for international guidelines on the use of CEUS in the liver has become apparent. The present document describes the third iteration of recommendations for the hepatic use of contrast enhanced ultrasound (CEUS) using contrast specific imaging techniques. This joint WFUMB-EFSUMB initiative has implicated experts from major leading ultrasound societies worldwide. These liver CEUS guidelines are simultaneously published in the official journals of both organizing federations (i.e., Ultrasound in Medicine and Biology for WFUMB and Ultraschall in der Medizin/European Journal of Ultrasound for EFSUMB). These guidelines and recommendations provide general advice on the use of all currently clinically available ultrasound contrast agents (UCA). They are intended to create standard protocols for the use and administration of UCA in liver applications on an international basis and improve the management of patients worldwide.

Hepatic incidentalomas

Recent advances in multidetector-row computed tomography, magnetic resonance imaging, and ultrasonography have led to the detection of incidental hepatic lesions in both the oncology and nononcology patient population that in the past remained undiscovered. These incidental hepatic lesions have created a management dilemma for both clinicians and radiologists. In this review, guidelines concerning the diagnosis and management of some of the more common hepatic incidentalomas are presented.

Terminology for contrast-enhanced sonography: a practical glossary

OBJECTIVE

The purpose of this glossary is to offer an updated guide to the correct terminology for contrast-enhanced sonography.

METHODS

This report was prepared by a panel of radiologists from the Sonography Section of the Italian Association of Medical Radiology. A leading author prepared a list of terms based on a comprehensive literature survey. The draft was analyzed by 3 experts on the topic of contrast-enhanced sonography. These reviewers reached a consensus and prepared the final version.

RESULTS

A list of 137 terms is included. These terms are briefly defined. Their proper application is discussed, with special reference to potential misleading uses.

CONCLUSIONS

Contrast-enhanced sonography is a relatively new diagnostic tool, now entering clinical practice in several countries. Use of appropriate, universal terminology is mandatory in the scientific setting to allow comparison between different published experiences. Additionally, use of clear, standardized terminology is necessary in the clinical setting to facilitate report understanding by the referring physician. Standardized, nonequivocal nomenclature may also help future diffusion of sonographic contrast media in countries where their application is still not approved.