Clinically useful diagnostic tool of contrast enhanced ultrasonography for focal liver masses: comparison to computed tomography and magnetic resonance imaging

Deep learning radiomics based on contrast-enhanced ultrasound images for assisted diagnosis of pancreatic ductal adenocarcinoma and chronic pancreatitis

BACKGROUND

Accurate and non-invasive diagnosis of pancreatic ductal adenocarcinoma (PDAC) and chronic pancreatitis (CP) can avoid unnecessary puncture and surgery. This study aimed to develop a deep learning radiomics (DLR) model based on contrast-enhanced ultrasound (CEUS) images to assist radiologists in identifying PDAC and CP.

METHODS

Patients with PDAC or CP were retrospectively enrolled from three hospitals. Detailed clinicopathological data were collected for each patient. Diagnoses were confirmed pathologically using biopsy or surgery in all patients. We developed an end-to-end DLR model for diagnosing PDAC and CP using CEUS images. To verify the clinical application value of the DLR model, two rounds of reader studies were performed.

RESULTS

A total of 558 patients with pancreatic lesions were enrolled and were split into the training cohort (n=351), internal validation cohort (n=109), and external validation cohorts 1 (n=50) and 2 (n=48). The DLR model achieved an area under curve (AUC) of 0.986 (95% CI 0.975-0.994), 0.978 (95% CI 0.950-0.996), 0.967 (95% CI 0.917-1.000), and 0.953 (95% CI 0.877-1.000) in the training, internal validation, and external validation cohorts 1 and 2, respectively. The sensitivity and specificity of the DLR model were higher than or comparable to the diagnoses of the five radiologists in the three validation cohorts. With the aid of the DLR model, the diagnostic sensitivity of all radiologists was further improved at the expense of a small or no decrease in specificity in the three validation cohorts.

CONCLUSIONS

The findings of this study suggest that our DLR model can be used as an effective tool to assist radiologists in the diagnosis of PDAC and CP.

Contrast-enhanced ultrasound is useful for the evaluation of focal liver lesions in children

Introduction

Contrast‐enhanced ultrasound (CEUS) is a widely used diagnostic method. In adults, it has been proven to be a useful alternative to CT and MRI for the characterisation of focal liver lesions (FLLs). However, since there is no official paediatric licensing for any ultrasound contrast agents in Europe, its use has been restricted.

Purpose

To retrospectively outline our experience with CEUS as a tool for the characterisation of FLLs in paediatric patients.

Methods

An eleven‐year retrospective single‐centre study. During this period, we identified 287 CEUS examinations performed on children, of these 36 were relevant first‐time examinations with the aim of characterising a focal liver lesion. Clinical and radiological data were collected from the hospital chart.

Results

The overall agreement between the CEUS diagnosis and the reference diagnosis for benign versus malignant differentiation was 75%. When analysing conclusive CEUS examinations only, the overall agreement was 96%. The specificity for correctly characterising a lesion as benign was 96%, and the negative predictive value was 100%. No side effects from CEUS were detected.

Conclusions

Our study reinforces that CEUS can be useful in the medical workup for the identification and classification of focal liver lesions in children.

Computed tomography for the diagnosis of hepatocellular carcinoma in adults with chronic liver disease

BACKGROUND

Hepatocellular carcinoma occurs mostly in people with chronic liver disease and ranks sixth in terms of global incidence of cancer, and fourth in terms of cancer deaths. In clinical practice, computed tomography (CT) is used as a second-line diagnostic imaging modality to confirm the presence of focal liver lesions suspected as hepatocellular carcinoma on prior diagnostic test such as abdominal ultrasound or alpha-foetoprotein, or both, either in surveillance programmes or in clinical settings. According to current guidelines, a single contrast-enhanced imaging study CT or magnetic resonance imaging (MRI) showing typical hallmarks of hepatocellular carcinoma in people with cirrhosis is valid to diagnose hepatocellular carcinoma. However, a significant number of hepatocellular carcinomas do not show typical hallmarks on imaging modalities, and hepatocellular carcinoma is, therefore, missed. There is no clear evidence of the benefit of surveillance programmes in terms of overall survival: the conflicting results can be a consequence of inaccurate detection, ineffective treatment, or both. Assessing the diagnostic accuracy of CT may clarify whether the absence of benefit could be related to underdiagnosis. Furthermore, an assessment of the accuracy of CT in people with chronic liver disease, who are not included in surveillance programmes is needed for either ruling out or diagnosing hepatocellular carcinoma.

OBJECTIVES

Primary: to assess the diagnostic accuracy of multidetector, multiphasic contrast-enhanced CT for the diagnosis of hepatocellular carcinoma of any size and at any stage in adults with chronic liver disease, either in a surveillance programme or in a clinical setting. Secondary: to assess the diagnostic accuracy of CT for the diagnosis of resectable hepatocellular carcinoma in adults with chronic liver disease.

SEARCH METHODS

We searched the Cochrane Hepato-Biliary Trials Register, Cochrane Hepato-Biliary Diagnostic-Test-Accuracy Studies Register, the Cochrane Library, MEDLINE, Embase, LILACS, Science Citation Index Expanded, and Conference Proceedings Citation Index - Science until 4 May 2021. We applied no language or document-type restrictions.

SELECTION CRITERIA

Studies assessing the diagnostic accuracy of CT for the diagnosis of hepatocellular carcinoma in adults with chronic liver disease, with cross-sectional designs, using one of the acceptable reference standards, such as pathology of the explanted liver and histology of resected or biopsied focal liver lesion with at least a six-month follow-up.

DATA COLLECTION AND ANALYSIS

At least two review authors independently screened studies, extracted data, and assessed the risk of bias and applicability concerns, using the QUADAS-2 checklist. We presented the results of sensitivity and specificity, using paired forest plots, and tabulated the results. We used a hierarchical meta-analysis model where appropriate. We presented uncertainty of the accuracy estimates using 95% confidence intervals (CIs). We double-checked all data extractions and analyses.

MAIN RESULTS

We included 21 studies, with a total of 3101 participants. We judged all studies to be at high risk of bias in at least one domain because most studies used different reference standards, often inappropriate to exclude the presence of the target condition, and the time-interval between the index test and the reference standard was rarely defined. Regarding applicability in the patient selection domain, we judged 14% (3/21) of studies to be at low concern and 86% (18/21) of studies to be at high concern owing to characteristics of the participants who were on waiting lists for orthotopic liver transplantation. CT for hepatocellular carcinoma of any size and stage: sensitivity 77.5% (95% CI 70.9% to 82.9%) and specificity 91.3% (95% CI 86.5% to 94.5%) (21 studies, 3101 participants; low-certainty evidence). CT for resectable hepatocellular carcinoma: sensitivity 71.4% (95% CI 60.3% to 80.4%) and specificity 92.0% (95% CI 86.3% to 95.5%) (10 studies, 1854 participants; low-certainty evidence). In the three studies at low concern for applicability (861 participants), we found sensitivity 76.9% (95% CI 50.8% to 91.5%) and specificity 89.2% (95% CI 57.0% to 98.1%). The observed heterogeneity in the results remains mostly unexplained. The sensitivity analyses, which included only studies with clearly prespecified positivity criteria and only studies in which the reference standard results were interpreted without knowledge of the results of the index test, showed no variation in the results.

AUTHORS' CONCLUSIONS

In the clinical pathway for the diagnosis of hepatocellular carcinoma in adults with chronic liver disease, CT has roles as a confirmatory test for hepatocellular carcinoma lesions, and for staging assessment. We found that using CT in detecting hepatocellular carcinoma of any size and stage, 22.5% of people with hepatocellular carcinoma would be missed, and 8.7% of people without hepatocellular carcinoma would be unnecessarily treated. For resectable hepatocellular carcinoma, we found that 28.6% of people with resectable hepatocellular carcinoma would improperly not be resected, while 8% of people without hepatocellular carcinoma would undergo inappropriate surgery. The uncertainty resulting from the high risk of bias in the included studies and concerns regarding their applicability limit our ability to confidently draw conclusions based on our results.

Diagnostic value of contrast-enhanced ultrasound versus computed tomography for hepatocellular carcinoma: a retrospective, single-center evaluation of 234 patients

OBJECTIVE

Hepatocellular carcinoma (HCC) is the most common cause of primary liver cancer. A major part of diagnostic HCC work-up is based on imaging findings from sonography, computed tomography (CT), or magnetic resonance imaging (MRI) scans. Contrast-enhanced ultrasound (CEUS) allows for the dynamic assessment of the microperfusion pattern of suspicious liver lesions. This study aimed to evaluate the diagnostic value of CEUS compared with CT scans for assessing HCC.

METHODS

We performed a retrospective, single-center study between 2004 and 2018 on 234 patients with suspicious liver lesions who underwent CEUS and CT examinations. All patients underwent native B-mode, color Doppler and CEUS after providing informed consent. Every CEUS examination was performed and interpreted by a single experienced radiologist (European Federation of Societies for Ultrasound in Medicine and Biology level 3).

RESULTS

CEUS was performed on all included patients without occurrence of any adverse effects. CEUS showed a sensitivity of 94%, a specificity of 70%, a positive predictive value of 93% and a negative predictive value of 72% for analyzing HCC compared with CT as the diagnostic gold standard.

CONCLUSIONS

CEUS has an excellent safety profile and shows a high diagnostic accuracy in assessing HCC compared with corresponding results from CT scans.

The diagnostic performance of contrast-enhanced ultrasound (CEUS) for evaluating hepatocellular carcinoma (HCC) juxtaposed to MRI findings; a retrospective single-center analysis of 292 patients

BACKGROUND

HCC is the most frequent primary liver cancer entity. Major risk factors comprise chronic HBC and HCV infections, ALD or NAFLD. Apart from the anamnesis, the clinical examination and serologic analysis, an essential part of the diagnostic HCC work-up is due to imaging findings from sonography, CT or MRI scans. HCC lesions feature a distinct vascularization pattern: hyperenhancement during early arterial and hypoenhancement/wash-out during portal venous or delayed phases. CEUS facilitates dynamic assessment of microperfusion patterns of suspicious liver lesions.

PURPOSE

The purpose of the present retrospective single-center study was to determine the diagnostic value of CEUS for assessing HCC by comparison with findings from MRI scans.

MATERIALS AND METHODS

Between 2004-2018 292 patients with suspicious liver lesions underwent CEUS and MRI. All patients underwent native B-mode, Color Doppler and CEUS after given informed consent. The applied contrast agent was a second-generation blood pool agent (SonoVue®, Bracco, Milan, Italy). Every CEUS examination was performed and interpreted by a single experienced radiologist (EFSUMB Level 3).

RESULTS

CEUS was performed on all included patients without occurrence of any adverse effects. CEUS showed a sensitivity of 96%, a specificity of 91%, a PPV of 95% and a NPV of 94% for analyzing HCC in comparison with MRI as the diagnostic gold standard.

CONCLUSION

With a distinguished safety profile CEUS shows a high diagnostic accuracy in assessing HCC compared to corresponding results from MRI scans.

Comparison between B-mode ultrasonography and contrast-enhanced ultrasonography for the surveillance of early stage pancreatic cancer: a retrospective study

Background

Contrast-enhanced ultrasonography (CE-US) brings a higher signal-to-noise ratio and a higher sensitivity for slow flow than traditional B-mode ultrasonography (US). However, it remains unclear whether CE-US is also superior to B-mode US in detecting early-stage pancreatic cancer (PC).

Methods

This was a retrospective study enrolling patients suspected of pancreatic insufficiency between June 2015 and December 2019. Enrolled patients successively received B-mode US and CE-US examinations, and some their demographic and clinical data were collected. The diagnostic capacity of the two examinations was calculated and receiver operating characteristic (ROC) curves was used to compare the area under the curve (AUC). A subgroup analysis was performed to explore the effects of tumor size on the diagnostic accuracy of B-mode US and CE-US.

Results

There were 128 patients enrolled in this study; 74 patients were diagnosed as early-stage PC patients and the remaining 54 were diagnosed with benign pancreatic lesions. The mean size of the PC was 17.8±4.9 mm. The results revealed that 68 of the 74 PC patients were correctly diagnosed by CE-US, and all 54 patients with benign pancreatic lesions were also correctly diagnosed. Meanwhile, only 55 of the 74 PC patients and 50 of the 54 patients with benign pancreatic lesions were diagnosed correctly using B-mode US. The ROC curve showed that the AUCs of CE-US and B-mode US were 0.959 and 0.835, respectively. According to the subgroup analysis, CE-US exhibited better accuracy than B-mode US for smaller tumors (size <20 mm, P=0.002; size <10 mm, P=0.043; size <5 mm, P=0.025).

Conclusions

CE-US was clearly superior to the conventional B-mode US in detecting early-stage PC, especially smaller sized PC.

Imaging Accuracy in Diagnosis of Different Focal Liver Lesions: A Retrospective Study in North of Iran

INTRODUCTION

Focal liver lesions (FLLs) are incidentally detected masses found in daily abdominal imaging which are necessary to be characterized, because of the potential of being malignant. There are several imaging methods, such as ultrasonography (US), computed tomography (CT scan), and contrast enhanced magnetic resonance imaging (MRI). Here, we evaluate and compare the diagnostic accuracy (i.e., sensitivity and specificity) of these imaging methods for the diagnosis of FLLs.

MATERIAL AND METHODS

In this retrospective study, patients with focal liver lesions included and based on the gastroenterologist decision, in 79 patients different imaging methods were used to determine the nature of FLLs: the US, CT scan, and MRI. At the next step, fine-needle aspiration biopsy (FNA) was performed in all cases, and the results about the true nature of FLLs compared with different imaging results. The chi-square test and McNemar test were used.

RESULTS

Ultrasound diagnosis of benign and malignant was obtained with 82% diagnosis accuracy, 100% sensitivity, 71.4% specificity, 100% negative predictive value, and 69.2% positive predictive value (PPV) compared with the biopsy. Also, the results of benign and malignant masses in CT scan were obtained with diagnostic accuracy of 95%, 100% sensitivity, 80% specificity, 93.9% positive predictive value, and 100% negative predictive value. MRI performed only in 2 cases with similar results to pathology.

CONCLUSION

It seems that CT scan is more appropriate and useful in the diagnosis of hepatic masses due to its higher diagnostic accuracy than the ultrasound.

Retrospective Analysis of Contrast-enhanced Ultrasonography Effectiveness in Reducing Time to Diagnosis and Imaging-related Expenditures at a Single Large United States County Hospital

Hepatic and renal lesions detected during ultrasound examinations frequently require subsequent contrast-enhanced computed tomography (CT) or magnetic resonance imaging (MRI) for characterization, delaying time to imaging diagnosis and increasing overall health care expenditures. Contrast-enhanced ultrasonography (CEUS) is a comparatively low-cost diagnostic tool that is underutilized in the evaluation of such indeterminate or suspicious hepatic and renal lesions. A retrospective chart review of CEUS examinations performed in our department demonstrated significantly shorter time to imaging diagnosis with CEUS compared to CT or MRI, largely due to the ability to perform the CEUS examination at the time of initial examination. For example mean time to completion for outpatient examinations was 5.2, 52.3, and 123.5 days for CEUS, CT, and MRI, respectively. The majority (78.4%) of CEUS examinations were completed the same day as the initial examination. Additionally, 66.7% of CEUS examinations were deemed diagnostic, abrogating further workup with CT or MRI in most cases. Annual imaging cost reduction of up to US $117,000 is anticipated in our institution based on projected reductions in follow-up CT and MRI examinations. These results indicate when CEUS was used as a first step to characterize both incidental lesions in patients without known risk factors for malignancy as well as suspicious lesions in patients with risk factors it can greatly reduce time to diagnosis and health care expenditures.

Multidisciplinary management of liver metastases in patients with colorectal cancer: a consensus of SEOM, AEC, SEOR, SERVEI, and SEMNIM

Colorectal cancer (CRC) has the second-highest tumor incidence and is a leading cause of death by cancer. Nearly 20% of patients with CRC will have metastases at the time of diagnosis, and more than 50% of patients with CRC develop metastatic disease during the course of their disease. A group of experts from the Spanish Society of Medical Oncology, the Spanish Association of Surgeons, the Spanish Society of Radiation Oncology, the Spanish Society of Vascular and Interventional Radiology, and the Spanish Society of Nuclear Medicine and Molecular Imaging met to discuss and provide a multidisciplinary consensus on the management of liver metastases in patients with CRC. The group defined the different scenarios in which the disease can present: fit or unfit patients with resectable liver metastases, patients with potential resectable liver metastases, and patients with unresectable liver metastases. Within each scenario, the different strategies and therapeutic approaches are discussed.

Contrast-enhanced US for characterization of focal liver lesions: a comprehensive meta-analysis

OBJECTIVES

This meta-analysis was performed to evaluate the accuracy of contrast-enhanced ultrasound (CEUS) in differentiating malignant from benign focal liver lesions (FLLs).

METHODS

Cochrane Library, PubMed and Web of Science databases were systematically searched and checked for studies using CEUS in characterization of FLLs. Data necessary to construct 2×2 contingency tables were extracted from included studies. The QUADAS tool was utilized to assess the methodologic quality of the studies. Meta-analysis included data pooling, subgroup analyses, meta-regression and investigation of publication bias was comprehensively performed.

RESULTS

Fifty-seven studies were included in this meta-analysis and the overall diagnostic accuracy in characterization of FLLs was as follows: pooled sensitivity, 0.92 (95%CI: 0.91-0.93); pooled specificity, 0.87 (95%CI: 0.86-0.88); diagnostic odds ratio, 104.20 (95%CI: 70.42-154.16). Subgroup analysis indicated higher diagnostic accuracy of the second-generation contrast agents (CAs) than the first-generation CA (Levovist; DOR: 118.27 vs. 62.78). Furthermore, Sonazoid demonstrated the highest diagnostic accuracy among three major CAs (SonoVue, Levovist and Sonazoid; DOR: 118.82 vs. 62.78 vs. 227.39). No potential publication bias was observed of the included studies.

CONCLUSION

CEUS is an accurate tool to stratify the risk of malignancy in FLLs. The second-generation CAs, especially Sonazoid may greatly improve diagnostic performance.

KEY POINTS

• CEUS shows excellent diagnostic accuracy in differentiating malignant from benign FLLs. • The second-generation CAs have higher diagnostic accuracy than first-generation CAs. • Sonazoid demonstrates the highest diagnostic accuracy among three major CAs.

Retrospective study on timing of resection of hepatocellular adenoma

Background

Hepatocellular adenoma (HCA) is a benign liver tumour that may be complicated by bleeding or malignant transformation. Present guidelines advise cessation of oral contraceptives and surgical resection if the lesion is still larger than 5 cm at 6 months after diagnosis. The aim of this study was to evaluate whether this 6-month interval is sufficient to expect regression of a large HCA to 5 cm or smaller.

Methods

This retrospective cohort study included all patients with an HCA larger than 5 cm diagnosed between 1999 and 2015 with follow-up of at least 6 months. Medical records were reviewed for patient characteristics, clinical presentation, lesion characteristics, management and complications. Differences in characteristics were assessed between patients kept under surveillance and those who underwent treatment for an HCA larger than 5 cm.

Results

Some 194 patients were included, of whom 192 were women. Eighty-six patients were kept under surveillance and 108 underwent HCA treatment. Patients in the surveillance group had a significantly higher BMI (P = 0·029), smaller baseline HCA diameter (P &lt; 0·001), more centrally located lesions (P &lt; 0·001) and were more likely to have multiple lesions (P = 0·001) than those in the treatment group. There were no significant differences in sex, age at diagnosis, symptoms, complication rates and HCA subtype distribution. Time-to-event analysis in patients managed conservatively and those still undergoing treatment more than 6 months after diagnosis showed that 69 of 118 HCAs (58·5 per cent) regressed to 5 cm or smaller after a median of 104 (95 per cent c.i. 80–128) weeks. Larger HCAs took longer to regress (P &lt; 0·001). No complications were documented during follow-up.

Conclusion

This study suggests that a 6-month cut-off point for assessment of regression of HCA larger than 5 cm to no more than 5 cm is too early. As no complications were documented during follow-up, the cut-off point in women with typical, non-β-catenin-activated HCA could be prolonged to 12 months, irrespective of baseline diameter.

Comparison of contrast-enhanced ultrasonograpy with Gd-EOB-DTPA-enhanced MRI in the diagnosis of liver metastasis from colorectal cancer

PURPOSE

To compare contrast-enhanced ultrasonography (CEUS) using Sonazoid with Gd-EOB-DTPA-enhanced MRI (EOB-MRI) in the diagnosis of liver metastases in patients with colorectal cancer.

METHODS

A total of 69 patients diagnosed with or suspected of having liver metastasis were enrolled. These hepatic lesions were diagnosed by histopathological examination after surgical resection or based on follow-up using various imaging modalities. The diagnostic accuracies of CEUS and EOB-MRI were compared.

RESULTS

One hundred thirty-three lesions were detected. Of these lesions, 109 were diagnosed as liver metastases. Of the 133 lesions, 90.2% were detected on CEUS, and 98.5% on EOB-MRI. One hundred nine lesions were diagnosed as liver metastasis. The areas under the receiver operating characteristic curve for diagnosis were 0.906 and 0.851 on CEUS and EOB-MRI, respectively (p = 0.41). Sensitivity, specificity, positive predictive value (PPV), negative predictive value, and overall accuracy were 90.8%, 84.5%, 97.1%, 67.1%, and 90.2%, respectively, for CEUS, and 95.4%, 70.8%, 93.7%, 77.3%, and 91%, respectively, for EOB-MRI.

CONCLUSIONS

CEUS has a higher specificity and PPV for the diagnosis of liver metastasis than EOB-MRI. © 2016 Wiley Periodicals, Inc. J Clin Ultrasound 45:138-144, 2017.

Evidence of good prognosis of hepatocellular adenoma in post-menopausal women

BACKGROUND & AIMS

Hepatocellular adenoma (HCA) is a rare benign liver tumor, which typically develops in women in their reproductive phase and is associated with the use of oral contraceptives. The aim of this study was to evaluate whether follow-up of HCA can be safely terminated after the occurrence of menopause. Secondary, we studied the impact of the diagnosis HCA on health-related quality of life (HRQoL).

METHODS

This was a cross-sectional cohort study, including 48 post-menopausal women with HCA. Patients underwent ultrasound examination and the size of HCA was compared to size at the last follow-up imaging (CT, MRI or ultrasound). HRQoL was evaluated by the Liver Disease Symptom Index 2.0 and Short Form 12.

RESULTS

Median time since last follow-up was 60.5months. In 44 patients 43.5% of the lesions were undetectable, 32.6% were stable in size and 19.6% became smaller. Mean diameter of HCA was 17.2mm compared to 35.9mm at last follow-up (p<0.001). There was a positive correlation between difference in size and time since last follow-up (p<0.001). No significant effect of HCA subtype on difference in size was found. Regarding HRQoL, study patients scored significantly lower on the mental component summary score compared to the general female Dutch population.

CONCLUSIONS

HCA diameter became significantly smaller after the occurrence of menopause and as time progresses, this regression increased. This suggests that routine follow-up of HCA <5cm in post-menopausal women after subsequent follow-up is not required. Notably we found that patient's mental HRQoL was inferior to that of the general population.

LAY SUMMARY

In this study we investigated if hepatocellular adenoma, a benign tumor of the liver that is found mostly in women and is associated with female hormones, regresses in size after the occurrence of menopause in female patients over 50years of age. We made an ultrasound of the liver lesion and found that the average size of the adenomas becomes significantly smaller. This could mean that female patients with a small (<5cm) hepatocellular adenoma who are post-menopausal do not have to remain in follow-up.

CLINICAL TRIAL NUMBER

MEC-2015-385.

Evaluation of the diagnostic accuracy of CEUS in children with benign and malignant liver lesions and portal vein anomalies

OBJECTIVE

Comparison of the diagnostic findings of MRI, CT and CEUS in children with benign and malignant and portal venous anomalies of the liver.

MATERIALS/METHODS

Retrospective analysis of the diagnostic findings of CEUS, MRI and CT scans in 56 children (age 0-17 years) with a total of 60 benign and malignant liver lesions and anomalies of the portal vein/perfusion. All patients underwent CEUS using sulphur hexafluoride microbubbles and a multi-frequency probe (1-5 MHz, 6-9 MHz). Cine-loops were stored up to 3 minutes. MRI was performed in 38 lesions. CT was performed in 8 lesions.

RESULTS

Out of the 56 patients 49 liver lesions (48 benign, 1 malignant), 9 anomalies of the portal vein/perfusion and 2 of the biliary system were detected. 16/49 lesions were analyzed histopathologically. Using CEUS, the characterization of the lesions was possible in 45 out of 49 cases. In 32 cases, CEUS provided the exact diagnosis. Only two benign lesions were falsely categorized as malignant.Findings of MRI and CEUS were concordant in 84% of cases (n = 32/38). CEUS considered 1 benign lesion to be malignant. 2 lesions were not detectable and in 3 lesions no definite diagnosis was established using MRI.Findings of CT and CEUS were concordant in 5 of 8 cases. In 21 lesions CEUS as the only imaging modality was found to be sufficient for diagnostics.

CONCLUSION

Despite the restricted indications for using CEUS in children, it offers a high diagnostic detection rate (93%) for characterization of liver lesions and portal vein anomalies.

Preoperative detection of hepatic metastases from colorectal cancer: Prospective comparison of contrast-enhanced ultrasound and multidetector-row computed tomography (MDCT)

PURPOSE

The goal of this study was to prospectively compare the sensitivity of contrast-enhanced ultrasound (CEUS) with that of multiphase multidetector-row computed tomography (MDCT) in the preoperative detection of hepatic metastases.

MATERIALS AND METHOD

Forty-eight patients, with a mean age of 62years old (range: 43-85years) were prospectively included. All patients underwent CEUS following intravenous administration of 2.4mL of an ultrasound contrast agent (Sonovue(®), Bracco, Milan, Italy) and multiphase MDCT. Intraoperative ultrasound examination (IOUS) was used as the standard of reference.

RESULTS

A total of 158 liver metastases were identified by IOUS, 127 by preoperative MDCT (sensitivity; 80.4%) and 102 by CEUS (sensitivity, 64.5%). The 15.9% difference in sensitivity between CEUS and MDCT was statistically significant (P=0.002). There was a disagreement between IOUS and CEUS in 23 patients (47%) and in 13 patients (27%) between IOUS and MDCT. MDCT identified one or more additional metastases in 10 patients (20%) resulting in a change in the surgical strategy.

CONCLUSION

Based on an unselected patient cohort and using multiphase MDCT, CEUS is significantly inferior to MDCT for the preoperative detection of hepatic metastases of colorectal cancer.

A comparative study of contrast enhanced ultrasound and contrast enhanced magnetic resonance imaging for the detection and characterization of hepatic hemangiomas

This study aims to compare contrast enhanced ultrasound (CEUS) and contrast enhanced magnetic resonance imaging (CEMRI) for the detection and characterization of hepatic hemangiomas. Included in this retrospective study were 83 histopathologically confirmed lesions of hemangioma in 66 hospitalized patients who underwent both CEUS and CEMRI and received surgery. The enhancement patterns on CEUS and CEMRI in each lesion were compared and analyzed. In addition, data obtained by the two modalities were then compared with the pathological findings to determine their value in differential diagnosis of hepatic hemangiomas. CEUS diagnosed 78 lesions of hemangioma against 80 by CEMRI. There were no statistical significant differences in the diagnostic value between CEUS and CEMRI in terms of sensitivity (88.0% vs. 92.8%), specificity (99.0% vs. 99.4%), accuracy (97.3% vs. 98.4%), positive predictive value (93.6% vs. 96.3%), and negative predictive value (98.0% vs. 98.8%) (p > 0.05, all). In the arterial phase, the main enhancement pattern on both CEUS and CEMRI was peripheral nodular enhancement (73 vs. 76), but lesions with diffuse enhancement on CEUS outnumbered those on CEMRI (3 vs. 1) and lesions with circular enhancement on CEMRI outnumbered those on CEUS (3 vs. 2). In the portal venous phase and delayed phase, the main enhancement pattern was hyperechoic change on CEUS and hyperintense on CEMRI (66 vs. 65), some lesions presented isoechoic change (12 vs. 15). These results suggested CEUS, an equivalent to CEMRI, may have an added diagnostic value in hemangiomas.

Imaging Diagnosis of Hepatocellular Carcinoma: Recent Advances of Contrast-Enhanced Ultrasonography with SonoVue®

Due to the ability to detect the typical contrast-imaging pattern for hepatocellular carcinoma (HCC), that is hyperenhancement in the arterial phase and hypoenhancement in the late phase on a cirrhotic background, contrast-enhanced ultrasonography (CEUS) was included in the American diagnostic algorithm for HCC in 2005. However, its role has been questioned because of the possibility of misdiagnosis of cholangiocarcinoma. The present review aims to describe the advantages and disadvantages of CEUS applications using Sonovue® for HCC. In particular there is focus on the accuracy of CEUS in detecting the typical HCC pattern, the CEUS patterns of intrahepatic cholangiocarcinoma (ICC), the risk of misdiagnosis with HCC, the diagnostic use of CEUS in cases of locoregional and systemic treatments, and the evaluation of response to antiangiogenic treatment using dedicated software.

Differential Diagnosis of Arterial Phase Enhanced Hepatic Inflammatory Lesions and Hepatocellular Carcinomas with Contrast-enhanced Ultrasound

We aimed to investigate the enhancement patterns of contrast-enhanced ultrasound (CEUS) with SonoVue and determine the utility of this method for differential diagnosis between hepatic inflammatory lesions with arterial phase enhancement and hepatocellular carcinomas (HCC). Twenty-three patients with arterial-enhanced inflammatory liver lesions and 46 HCC patients were included. These lesions had been subjected to CEUS examination and confirmed by pathologic results or imaging follow-up for at least 1 y. In the arterial phase of CEUS, 65.2% of the inflammatory lesions showed patchy (slight enhancement with poorly defined margins) or centripetal enhancement, whereas 89.1% of the HCC lesions showed homogeneous or heterogeneous enhancement (p < 0.001). Moreover, 82.6% of the inflammatory lesions had poorly defined margins, and 78.3% were irregular in shape at the peak, whereas 87.0% of the HCC lesions had well-defined margins and 76.1% were regular (both p < 0.001). Feeding vessels were more frequently visualized in HCCs (71.7%) than in inflammatory lesions (26.1%, p < 0.001). Additionally, 88.2% of the internal non-perfused areas in inflammatory lesions were regular in shape, while 68.0% of these areas in HCCs had an irregular shape (p < 0.001). CEUS pattern analysis provides important information for differentiating inflammatory liver lesions and HCCs and is helpful for improving diagnostic accuracy.

[Focal nodular hyperplasia and hepatocellular adenoma]

CLINICAL ISSUE

Focal nodular hyperplasia (FNH) and hepatocellular adenoma (HCA) are liver lesions of hepatocellular origin. The FNH is a commonly occurring hepatic lesion whereas HCA is very rare. Non-invasive differentiation between HCA subtypes and atypical FNH may pose a diagnostic challenge as both entities predominantly occur in middle-aged female patients.

STANDARD RADIOLOGICAL METHODS

The conventional imaging modalities include ultrasound (US), computed tomography (CT) and magnetic resonance imaging (MRI). Distinguishing FNH from HCA is of great importance clinically as FNH is considered to be a benign lesion and needs no further management. In contrast HCA is considered to be a borderline tumor due to the risk of hemorrhage, growth and even malignant transformation and requires individualized management.

METHODOLOGICAL INNOVATIONS

The above mentioned radiological procedures usually enable an accurate and certain diagnosis of a typical FNH to be achieved. In cases of atypical FNH, particularly in patients with a clinical history of malignancy, these imaging modalities are insufficient to establish a clear diagnosis. In this scenario, the use of modern hepatobiliary contrast-enhanced MRI will enable a differentiation between FNH and metastasis with a high sensitivity and specificity. Furthermore, it allows a differentiation of FNH from 90 % of adenoma subtypes.

ACHIEVEMENTS

This article describes the histopathological and radiological features of these lesions and explains the advantages and limitations of various imaging modalities used for the diagnosis and differentiation of these entities.

PRACTICAL RECOMMENDATIONS

The new classification of HCAs according to phenotype and genotype and their imaging features, as well as different enhancement patterns, are described. The correlation between HCA subtypes and their individual management are also discussed.

Effects of Gray-Scale Ultrasonography Immediate Post-Contrast on Characterization of Focal Liver Lesions

This study compared the imaging features of conventional gray scale ultrasound (US) before and after contrast-enhanced ultrasound (CEUS) for focal liver lesions and 22 evaluated the role of US post-CEUS in characterizing liver lesions. 126 patients with 158 focal liver lesions underwent CEUS and US post-CEUS examination and entered this study. There were 74 hepatocellular carcinomas (HCC), 43 hepatic metastases, and 41 hemangiomas. Imaging features of US pre-CEUS and US post-CEUS were analyzed offsite by two blinded experienced radiologists to evaluate size, boundary, echogenicity, internal texture, posterior acoustic enhancement, spatial resolution, and contrast resolution. In the end with pathological and clinical evidence, the diagnostic accuracy rate of US pre-CEUS was 53.8% (85/158 lesions), lower than that of CEUS (88.0%, 139/158 lesions); with the complementation of US post-CEUS the rate rose to 93.0% (147/158 lesions). US post-CEUS could improve the visibility of typical structures of focal liver lesions and might provide important complementary information for CEUS diagnosis. It also increases the visibility of small liver lesions compared with US pre-CEUS and helps to guide local interventional procedure.

Diagnosis and treatment of hepatocellular carcinoma: An update

Hepatocellular carcinoma (HCC) is one of the most common malignancies leading to high mortality rates in the general population; in cirrhotic patients, it is the primary cause of death. The diagnosis is usually delayed in spite of at-risk population screening recommendations, i.e., patients infected with hepatitis B or C virus. Hepatocarcinogenesis hinges on a great number of genetic and molecular abnormalities that lead to tumor angiogenesis and foster their dissemination potential. The diagnosis is mainly based on imaging studies such as computed tomography and magnetic resonance, in which lesions present a characteristic classical pattern of early arterial enhancement followed by contrast medium “washout” in late venous phase. On occasion, when imaging studies are not conclusive, biopsy of the lesion must be performed to establish the diagnosis. The Barcelona Clinic Liver Cancer staging method is the most frequently used worldwide and recommended by the international guidelines of HCC management. Currently available treatments include tumor resection, liver transplant, sorafenib and loco-regional therapies (alcoholization, radiofrequency ablation, chemoembolization). The prognosis of hepatocarcinoma is determined according to the lesion’s stage and in cirrhotic patients, on residual liver function. Curative treatments, such as liver transplant, are sought in patients diagnosed in early stages; patients in more advanced stages, were not greatly benefitted by chemotherapy in terms of survival until the advent of target molecules such as sorafenib.