Contrast enhanced ultrasound (CEUS) imaging of solid benign focal liver lesions

Specific imaging features indicate the clinical features of patients with hepatic perivascular epithelioid cell tumor by comparative analysis of CT and ultrasound imaging

Objective

The objective of the study was to explore the CT and ultrasound features and clinical significance of perivascular epithelioid cell tumor (PEComa) of the liver.

Methods

Eleven hepatic PEComa patients treated in our hospital were retrospectively analyzed based on the characteristics of the imaging results of the patients, including conventional ultrasound, CDFI, contrast-enhanced ultrasound (CEUS), and contrast-enhanced CT (CECT).

Results

CT scans showed that all lesions were hypodense. Ultrasonography showed that lesions were either hyperechoic (4/11, 36.36%), hypoechoic (4/11, 36.36%), isoechoic (1/11, 9.09%), or heterogeneously echoic (2/11, 18.18%). CDFI showed that most of the lesions had an abundant blood supply (9/11, 81.82%). Whether on CT scan or ultrasonography, the margins of the lesions were dominated by clear margins. Ultrasonography revealed more features: hyperechoic patterns around lesions (3/11, 27.27%) and lateral shadow (5/11, 45.45%). The CDFI showed that large blood vessels were observed around the lesions (9/11, 81.82%). CECT shows two enhancement patterns: “fast in and fast out (FIFO)” (8/11, 72.72%) and “fast in and slow out (FISO)” (3/11, 27.27%). CEUS shows that all lesions had the enhancement pattern of “FISO,” which was different from CECT. All lesions displayed rapid enhancement during HAP in CEUS during 7–20 s. Four patients (36.36%) washed out at 60–180 s, another four (36.36%) washed out at 180–300 s, and the remaining three patients (27.27%) showed no signs of washout even at 360 s.

Conclusion

Some imaging features, such as clear margins, peripheral hyperechoic around the lesion, lateral shadow, the large blood vessels around lesions, and the “FISO” enhancement pattern, may indicate expansive growth of the tumor and be helpful in the diagnosis of PEComa. Ultrasound images may provide more details for clinical reference.

Contrast-Enhanced Ultrasound Features of Histopathologically Proven Hepatocellular Carcinoma in the Non-cirrhotic Liver: A Multicenter Study

Current literature on the role of contrast-enhanced ultrasound (CEUS) in the diagnosis of hepatocellular carcinoma (HCC) in non-cirrhotic patients is limited. The aim of this retrospective multicenter study was to analyze CEUS features of histologically proven HCC in patients with non-cirrhotic liver. In this multicenter study, 96 patients from eight medical institutions with histologically proven HCC lesions in non-cirrhotic liver were retrospectively reviewed regarding SonoVue-enhanced CEUS features. Two ultrasound experts assessed the CEUS enhancement pattern and came to a consensus using the World Federation of Societies for Ultrasound in Medicine and Biology guideline criteria. The mean size of HCC lesions included was 60.3 ± 37.8 mm (mean ± standard deviation). Most of the lesions were heterogeneous but predominantly hypo-echoic on B-mode ultrasound (64.5%, 62/96), with ill-defined margins and irregular shapes. During the arterial phase of CEUS, most of the HCC lesions in non-cirrhotic liver exhibited heterogeneous hyperenhancement (78.1%, 75/96) compared with the surrounding liver parenchyma. Almost 30% of HCC lesions (28.1%, 27/96) exhibited early wash-out (<60 s). All lesions exhibited wash-out and hypo-enhancement in the late phase. CEUS features of HCC lesions in non-cirrhotic patients typically include hyperenhancement in the arterial phase and relatively rapid wash-out in the portal venous phase, which is different from HCC in cirrhotic livers and more similar to liver metastasis.

Echinococcosis: a Challenge for Liver Sonography

The sonographic findings in alveolar echinococcosis (AE) and cystic echinococcosis (CE) are complex and can pose significant differential diagnostic problems. They may present like complicated cysts or malignant tumors in the liver. We will discuss the diagnostic difficulties and pitfalls of these two diseases based on case histories.

Clinical value of contrast-enhanced computed tomography (CECT) combined with contrast-enhanced ultrasound (CEUS) for characterization and diagnosis of small nodular lesions in liver

Objectives

To explore the clinical value of contrast-enhanced computed tomography (CECT) combined with contrast-enhanced ultrasound (CEUS) for characterization and diagnosis of small nodular lesions in the liver and investigate the association between such small nodular lesions and the degree of tumor differentiation.

Methods

Combined imaging modalities were performed on 120 patients who were admitted by Linyi Maternal and Child Health hospital from December 2018 to December 2020 and diagnosed with hepatic nodular lesions. The CT scans were interpreted by two senior imageologists while the ultrasound scans were analyzed by two senior sonographers. A comparative analysis was carried out on different scan modes and the postoperative or post-puncture pathological results using the t-test, the χ2 test, and the Pearson's correlation analysis.

Results

Compared to the pathological results, definite diagnoses of 55 malignant cases were made using CECT alone, with the coincidence rate of 78.6%; CECT combined with CEUS formed correct diagnoses in 64 cases, and the coincidence rate was up to 91.4%. The difference between the two scan modes was statistically significant (p= 0.03). Based on pathological diagnosis, seventy out of the 120 cases of small nodular lesions were identified as malignant, while the other 50 cases were benign. The single imaging modality diagnosed 63 malignant and 57 benign nodules, whereas the combined modalities identified 68 malignancies and 52 benign conditions. Compared to CECT as a single imaging modality, the combined modalities showed a higher degree of sensitivity and accuracy, and the difference was statistically significant (sensitivity: p= 0.03; accuracy: p= 0.02); in the malignant cases, the magnitudes of contrast enhancement of CT and ultrasound imaging decreased with an increase in the degree of differentiation, indicating a negative correlation between these factors.

Conclusions

CECT combined with CEUS has a higher coincidence rate, greater sensitivity, and better diagnostic accuracy when being used for characterization and diagnosis of small nodular lesions in the liver. A higher degree of tumor differentiation means a decreased magnitude of contrast enhancement and a blurrier boundary, which indicates that CECT and CEUS are complementary to each other in classifying malignant liver nodules. The use of the combined imaging modalities shows clinical value for characterizing small liver nodules and predicting the degree of malignancy.

Contrast-Enhanced Ultrasound as a Main Radiological Diagnostic Method for Primary Liver Neoplasms and Hemangiomas

Contrast-enhanced ultrasound (CEUS) is a relatively new approach for the definitive diagnosis of focal liver lesions (FLL). The essential advantages of CEUS are affordability, absence of radiation, and negligible nephrotoxicity-making this diagnostic approach more preferable.

This review includes data from 39 different research studies published during the last 10 years, selected through the MeSH strategy in PubMed.

We conclude that CEUS is a promising approach for diagnosing primary liver neoplasms and it is an excellent radiological approach for children and pregnant women because of the absence of radiation and nephrotoxicity. Studies showed that CEUS is a very good approach for the differentiation of a variety of hemangiomas and for a detailed description of those findings. Therefore, CEUS is an important and progressive method for the diagnosis of liver neoplasms. The regular use of CEUS will facilitate the diagnosis of primary liver lesions.

Values of Contrast-Enhanced Ultrasound in Classification and Diagnosis of Common Bile Duct and Superficial Organ Lesions under Compression Algorithm

This work aimed to investigate values of contrast-enhanced ultrasound (CEUS) under DEFLATE in the classification and diagnosis of the common bile duct and superficial lymphoid lesions. 88 patients with lower common bile duct lesions and 126 patients with superficial lymphoid lesions were selected as the subjects investigated and examined by CEUS under DEFLATE to compare characteristics and diagnostic efficiency of CEUS in different types of lesions. The time-intensity curve (TIC) was for quantitative analysis on CEUS results. The results showed that there were statistically significant differences in the comparison of time to peak (TTP), area under the curve (AUC), and gradient (Grad) of common bile duct walls in patients from the malignant group (P < 0.05), while the comparison of three indicators of patients in the benign group was not statistically remarkable (P > 0.05). In addition, there were statistically great differences in TTP, AUC, and Grad among patients in the benign and malignant groups (P < 0.05). The sensitivity, specificity, accuracy, and positive/negative predictive value of CEUS + ultrasound (US) in the diagnosis of benign and malignant lymph nodes were 92.83%, 87.14%, 89.54%, 91.23%, and 86.43%, respectively. The values of maximal intensity (I_max) in the reactive hyperplasia group (group A), lymphoma group (group B), and metastatic lymph nodes group (group C) were compared, showing statistical differences (P < 0.05). The TTP and AUC of group B were higher than those of groups A and C, respectively (P < 0.05), and the base-to-peak ascending slope (K_UP) and the absolute value of the semidescending slope (K_DOWN) in group C increased hugely compared to group A (P < 0.05). It indicated that CEUS examination under DEFLATE could be applied in the qualitative diagnosis of lower common bile duct lesions and superficial lymphoid lesions, which was worthy of clinical application.

Relationship between quantitative contrast-enhanced ultrasonography parameters and angiogenesis in primary small hepatocellular carcinoma: A retrospective study

To analyze the correlation between quantitative contrast-enhanced ultrasonography (CEUS) parameters and angiogenesis in primary small hepatocellular carcinoma (sHCC) with varying degrees of differentiation.According to varying degrees of differentiation, a total of 90 primary sHCC patients admitted to our hospital from July 2018 to January 2020 were selected and divided into poorly differentiated group (24 cases), moderately differentiated group (31 cases), and highly differentiated group (35 cases). All patients received real-time CEUS before surgery. The tumor diameter, microvascular morphology, grading of color blood flow, contrast-enhanced performance in different phases, quantitative CEUS parameters, expression of angiogenesis-related genes, and microvessel density (MVD) were compared among the 3 groups. The correlation between quantitative parameters of CEUS and angiogenesis indexes was analyzed by Spearman rank correlation analysis.Spearman rank correlation analysis showed that vascular endothelial growth factor (VEGF), platelet-derived growth factor (PDGF), epidermal growth factor receptor (EGFR), and angiopoietin-2 (Ang-2) expression and MVD were negatively correlated with the time to peak (TTP), wash-out time, and peak accelerating time (PAT) (r < 0, P < .05), and were positively correlated with enhancing slope rate (ESR) and peak intensity increasing rate (PIIR) (r > 0, P < .05).CEUS is able to identify varying degrees of differentiation in primary sHCC, and the quantitative CEUS parameters are closely related to angiogenesis.

Ultrasound findings in peliosis hepatis

Purpose

The aim of this study was to retrospectively evaluate contrast-enhanced ultrasound (CEUS) findings in patients with peliosis hepatis (PH).

Methods

A retrospective analysis was conducted of CEUS features in 24 patients with histopathologically confirmed PH (11 men and 13 women; mean age, 32.4±7.1 years; range, 28 to 41 years). All lesions were histologically proven, either by core needle biopsy (n=10) or by hepatic surgery (n=14).

Results

The mean size was 36.8±12.4 mm (range, 10 to 80 mm). On B-mode ultrasonography (BMUS), all PH lesions were heterogeneously hypoechoic, with well-defined margins but irregular shapes. No mass effect was observed. During the arterial phase of CEUS, all lesions displayed mild heterogeneous hyperenhancement (83.3%, 20/24) or isoenhancement (16.7%, 4/24). Furthermore, 87.5% of the PH lesions showed mild washout after 1 minute in the portal venous phase (30-120 seconds) and mild washout in the late phase (>120 seconds).

Conclusion

The lack of a mass effect on BMUS, mild heterogeneous arterial hyperenhancement, and washout in the very late portal venous phase (after 1 minute) on CEUS are characteristic of PH. Although it is a histological diagnosis, PH should be considered in the differential diagnosis when the clinical context does not favor a malignancy or infection.

Robotic resection of liver focal nodal hyperplasia guided by indocyanine green fluorescence imaging: A preliminary analysis of 23 cases

BACKGROUND

Focal nodal hyperplasia (FNH) is a common benign tumor of the liver. It occurs mostly in people aged 40-50 years and 90% of the patients are female. FNH can be cured by local resection. How to locate and judge the tumor boundary in real time is often a challenge for surgeons.

AIM

To summarize the technique and feasibility of robotic resection of FNH guided by indocyanine green (ICG) fluorescence imaging.

METHODS

The demographics and perioperative outcomes of a consecutive series of patients who underwent robotic resection of liver FNH guided by ICG fluorescence imaging between May 1, 2018 and September 30, 2019 were retrospectively analyzed. ICG was injected through the median elbow vein in all the patients at a dose of 0.25 mg/kg 48 h before the operation. During the operation, the position of FNH in the liver was located in the fluorescence mode of the Da Vinci Si robot operating system and the tumor boundary was determined during the resection.

RESULTS

Among the 23 patients, there were 11 males and 12 females, with a mean age of 30.5 ± 9.3 years. Twenty-two cases completed robotic resection, while one (4.3%) case converted to open surgery. In the robotic surgery group, the operation time was 35-340 min with a median of 120 min, the intraoperative bleeding was 10-800 mL with a median of 50 mL, and the postoperative hospital stay was 1-7 d with a median of 4 d. Biliary fistula occurred in two (8.7%) patients after robotic operation and they both recovered after conservative treatment. One (4.3%) patient received blood transfusion and there was no death in this study. The postoperative hospital stay in the small tumor group was significantly shorter than that in the large tumor group (P < 0.05).

CONCLUSION

ICG fluorescence imaging can guide the surgeon to perform robotic resection of liver FNH by locating the tumor and displaying the tumor boundary in real time. It is a safe and feasible method to ensure the complete resection of the tumor.

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.

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.

Ultrasound imaging of abdominal sarcoidosis: State of the art

Since it has been recognized that sarcoidosis (SA) is not an exclusive disorder of the lungs but can also affect other organs such as the liver and spleen, efforts have been made to define specific imaging criteria for the diagnosis of the single organ involvement, and the concept has been reinforced that the exclusion of alternative causes is important to achieve the correct diagnosis. Ultrasound (US) is a useful tool to evaluate patients with suspected abdominal SA, such as of the liver, spleen, kidney, pancreas and other organs, showing findings such as organomegaly, focal lesions and lymphadenopathy. While the diagnosis of abdominal SA is more predictable in the case of involvement of other organs (e.g., lungs), the problem is more complex in the case of isolated abdominal SA. The recent use of contrast-enhanced ultrasound and endoscopic ultrasound elastography has provided additional information about the enhancement patterns and tissue rigidity in abdominal SA. Here we critically review the role of US in abdominal SA, reporting typical findings and limitations of current evidence and by discussing future perspectives of study.

Ultrasound Imaging of Hepatocellular Adenoma Using the New Histology Classification

Hepatocellular adenoma is a rare benign liver tumor. Predisposing factors include hepatic storage diseases and some genetic conditions. A new histology-based classification has been proposed but to date, the corresponding ultrasound imaging features have not been reported. Here we review the new classification scheme and discuss the corresponding features on contrast-enhanced ultrasound imaging.