Characterisation of focal liver lesions undetermined at grey-scale US: contrast-enhanced US vs 64-row MDCT and MRI with liver-specific contrast agent. Radiol Med. 2010;115:714-731. [PMID: 20082225 DOI: 10.1007/s11547-010-0506-3]

Hydralazine-augmented contrast ultrasound imaging improves the detection of hepatocellular carcinoma

BACKGROUND

Hepatocellular carcinoma (HCC) detection with B-mode and contrast-enhanced ultrasound (CUS) imaging often varies between subjects, especially in patients with background cirrhosis. Various factors contribute to this variability, including the tumor blood flow, tumor size, internal echoes, and its location in livers with diffuse fibro-cirrhotic changes.

OBJECTIVE

Towards improving lesion detection, this study evaluates a vasodilator, hydralazine, to enhance the visibility of HCC by reducing its blood flow relative to the surrounding liver tissue.

METHODS

HCC were analyzed for tumor visibility measured for B-mode, CUS, and hydralazine-augmented-contrast ultrasound (HyCUS) in an autochthonous HCC rat model. 21 tumors from 12 rats were studied. B-mode and CUS images were acquired before hydralazine injection. Rats received an intravenous hydralazine injection of 5 mg/kg, then images were acquired 20 min later. Four rats were used as controls. The difference in echo intensity of the lesion and the surrounding tissue was used to determine the visibility index (VI).

RESULTS

The visibility index for HCC was found to be significantly improved with the use of HyCUS imaging compared to traditional B-mode and CUS imaging. The visibility index for HCC was 16.5 ± 2.8 for HyCUS, compared to 5.3 ± 4.8 for B-mode and 4.1 ± 3.8 for CUS. The differences between HyCUS and the other imaging modalities were statistically significant, with p-values of 0.001 and 0.02, respectively. Additionally, when compared to control cases, HyCUS showed higher discrimination of HCC (VI = 6.4 ± 1.2) with a p-value of 0.003, while B-mode (VI = 6.7 ± 1.4, p = 0.5) and CUS (VI = 6.4 ± 1.2, p = 0.3) showed lower discrimination.

CONCLUSION

Vascular blood flow modulation by hydralazine enhances the visibility of HCC. HyCUS offers a potential problem-solving method for detecting HCC when B-mode and CUS are unsuccessful, especially with background fibro-cirrhotic liver disease. Future evaluation of the approach in humans will determine its translatability for clinical applications.

Contrast-enhanced ultrasound for assessing blood flow modulation of hepatocellular carcinoma by hydralazine

Modulating aberrant tumor microvasculature provides unique opportunities for enhancing ultrasound imaging of hepatocellular carcinoma (HCC). This study aims to use contrast-enhanced ultrasound to evaluate the potential of a potent vasodilator, hydralazine, to attenuate blood flow in HCC while enhancing it in the surrounding liver tissue. The "steel effect," where blood flow is diverted from the lesion to the surrounding tissue aims to enhance lesion-tissue contrast. Methods: HCC was induced in six rats by oral ingestion of diethylnitrosamine for 12 weeks. 10 tumors were studied to assess the enhancement in HCC tumors and surrounding tissue. Contrast-enhanced ultrasound images (CEUS) of each tumor were acquired before and after hydralazine injection. The enhancement of images was analyzed for the qualitative and quantitative assessment of HCC enhancement. Peak enhancement (PE) was calculated, representing the maximum signal intensity reached during the transit of the contrast bolus for both the tumor and the surrounding tissue. Intravenous administration of hydralazine significantly reduced CEUS signals in HCC tumors. The visual examination of images showed that the enhancement of tumors dramatically decreased after hydralazine injection. On the other hand, the surrounding tissue showed an increased enhancement. PE for the HCC changed from (71.8 ± 5) pre hydralazine to (28.7± 4.9), a 61.7% reduction after hydralazine injection, p=0.01. Future studies validating the technique in clinical settings for enhancing lesion-tissue contrast may allow physicians greater precision and accuracy in HCC surveillance for early detection of small tumors.

Development of an abdominal phantom for the validation of an oligometastatic disease diagnosis workflow

PURPOSE

The liver is a common site for metastatic disease, which is a challenging and life-threatening condition with a grim prognosis and outcome. We propose a standardized workflow for the diagnosis of oligometastatic disease (OMD), as a gold standard workflow has not been established yet. The envisioned workflow comprises the acquisition of a multimodal image dataset, novel image processing techniques, and cone beam computed tomography (CBCT)-guided biopsy for subsequent molecular subtyping. By combining morphological, molecular, and functional information about the tumor, a patient-specific treatment planning is possible. We designed and manufactured an abdominal liver phantom that we used to demonstrate multimodal image acquisition, image processing, and biopsy of the OMD diagnosis workflow.

METHODS

The anthropomorphic abdominal phantom contains a rib cage, a portal vein, lungs, a liver with six lesions, and a hepatic vessel tree. This phantom incorporates three different lesion types with varying visibility under computed tomography (CT), magnetic resonance imaging (MRI), and positron emission tomography CT (PET-CT), which reflects clinical reality. The phantom is puncturable and the size of the corpus and the organs is comparable to those of a real human abdomen. By using several modern additive manufacturing techniques, the manufacturing process is reproducible and allows to incorporate patient-specific anatomies. As a first step of the OMD diagnosis workflow, a pre-interventional CT, MRI, and PET-CT dataset of the phantom was acquired. The image information was fused using image registration and organ information was extracted via image segmentation. A CBCT-guided needle puncture experiment was performed, where all six liver lesions were punctured with coaxial biopsy needles.

RESULTS

Qualitative observation of the image data and quantitative evaluation using contrast-to-noise ratio (CNR) confirms that one lesion type is visible only in MRI and not CT. The other two lesion types are visible in CT and MRI. The CBCT-guided needle placement was performed for all six lesions, including those visible only in MRI and not CBCT. This was possible by successfully merging multimodal pre-interventional image data. Lungs, bones, and liver vessels serve as realistic inhibitions during needle path planning.

CONCLUSIONS

We have developed a reusable abdominal phantom that has been used to validate a standardized OMD diagnosis workflow. Utilizing the phantom, we have been able to show that a multimodal imaging pipeline is advantageous for a comprehensive detection of liver lesions. In a CBCT-guided needle placement experiment we have punctured lesions that are invisible in CBCT using registered pre-interventional MRI scans for needle path planning. This article is protected by copyright. All rights reserved.

Radiological assessment of secondary biliary tree lesions: an update

Objective

To conduct a systematic literature review of imaging techniques and findings in patients with peribiliary liver metastasis.

Methods

Several electronic datasets were searched from January 1990 to June 2017 to identify studies assessing the use of different imaging techniques for the detection and staging of peribiliary metastases.

Results

The search identified 44 studies, of which six met the inclusion criteria and were included in the systematic review. Multidetector computed tomography (MDCT) is the technique of choice in the preoperative setting and during the follow-up of patients with liver tumors. However, the diagnostic performance of MDCT for the assessment of biliary tree neoplasms was low compared with magnetic resonance imaging (MRI). Ultrasound (US), without and with contrast enhancement (CEUS), is commonly employed as a first-line tool for evaluating focal liver lesions; however, the sensitivity and specificity of US and CEUS for both the detection and characterization are related to operator expertise and patient suitability. MRI has thus become the gold standard technique because of its ability to provide morphologic and functional data. MRI showed the best diagnostic performance for the detection of peribiliary metastases.

Conclusions

MRI should be considered the gold standard technique for the radiological assessment of secondary biliary tree lesions.

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.

Interobserver agreement for contrast-enhanced ultrasound of liver imaging reporting and data system: A systematic review and meta-analysis

BACKGROUND

Hepatocellular carcinoma is the most common primary liver malignancy. From the results of previous studies, Liver Imaging Reporting and Data System (LI-RADS) on contrast-enhanced ultrasound (CEUS) has shown satisfactory diagnostic value. However, a unified conclusion on the interobserver stability of this innovative ultrasound imaging has not been determined. The present meta-analysis examined the interobserver agreement of CEUS LI-RADS to provide some reference for subsequent related research.

AIM

To evaluate the interobserver agreement of LI-RADS on CEUS and analyze the sources of heterogeneity between studies.

METHODS

Relevant papers on the subject of interobserver agreement on CEUS LI-RADS published before March 1, 2020 in China and other countries were analyzed. The studies were filtered, and the diagnostic criteria were evaluated. The selected references were analyzed using the “meta” and “metafor” packages of R software version 3.6.2.

RESULTS

Eight studies were ultimately included in the present analysis. Meta-analysis results revealed that the summary Kappa value of included studies was 0.76 [95% confidence interval, 0.67-0.83], which shows substantial agreement. Higgins I² statistics also confirmed the substantial heterogeneity (I² = 91.30%, 95% confidence interval, 85.3%-94.9%, P < 0.01). Meta-regression identified the variables, including the method of patient enrollment, method of consistency testing, and patient race, which explained the substantial study heterogeneity.

CONCLUSION

CEUS LI-RADS demonstrated overall substantial interobserver agreement, but heterogeneous results between studies were also obvious. Further clinical investigations should consider a modified recommendation about the experimental design.

CEUS LI-RADS: a pictorial review

Contrast-enhanced ultrasound (CEUS) greatly improved the diagnostic accuracy of US in the detection and characterization of focal liver lesions (FLLs), and it is suggested and often included in many international guidelines as an important diagnostic tool in the imaging work-up of cirrhotic patients at risk for developing hepatocellular carcinoma (HCC). In particular, CEUS Liver Imaging Reporting and Data System (LI-RADS) provides standardized terminology, interpretation, and reporting for the diagnosis of HCC. The aim of this pictorial essay is to illustrate CEUS features of nodules discovered at US in cirrhotic liver according to LI-RADS categorization.

Contrast-enhanced ultrasound of hepatocellular carcinoma: where do we stand?

Contrast-enhanced ultrasound (CEUS) represents a significant breakthrough in ultrasonography (US), and it is being increasingly used for the evaluation of focal liver lesions (FLLs). CEUS is unique in that it allows non-invasive assessment of liver perfusion in real time throughout the vascular phase, which has led to dramatic improvements in the diagnostic accuracy of US in the detection and characterization of FLLs, the choice of therapeutic procedures, and the evaluation of response. Currently, CEUS is included as a part of the suggested diagnostic work-up of FLLs, including in cirrhotic patients with hepatocellular carcinoma, resulting in better patient management and cost-effective delivery of therapy.

Expert consensus on multidisciplinary therapy of colorectal cancer with lung metastases (2019 edition)

The lungs are the second most common site of metastasis for colorectal cancer (CRC) after the liver. Rectal cancer is associated with a higher incidence of lung metastases compared to colon cancer. In China, the proportion of rectal cancer cases is around 50%, much higher than that in Western countries (nearly 30%). However, there is no available consensus or guideline focusing on CRC with lung metastases. We conducted an extensive discussion and reached a consensus of management for lung metastases in CRC based on current research reports and the experts' clinical experiences and knowledge. This consensus provided detailed approaches of diagnosis and differential diagnosis and provided general guidelines for multidisciplinary therapy (MDT) of lung metastases. We also focused on recommendations of MDT management of synchronous lung metastases and initial metachronous lung metastases. This consensus might improve clinical practice of CRC with lung metastases in China and will encourage oncologists to conduct more clinical trials to obtain high-level evidences about managing lung metastases.

Contribution of 3-Dimensional Contrast-Enhanced Ultrasonography (CEUS) Compared With 2-Dimensional CEUS in the Analysis of Liver Tumors

OBJECTIVES

In this study, we investigated the vascular characteristics of liver tumors on 3-dimensional (3D) and 2-dimensional (2D) contrast-enhanced ultrasonography (CEUS). The clinical value of these CEUS methods in the diagnosis of benign and malignant liver tumors was evaluated and compared.

METHODS

A total of 126 liver tumors were examined by conventional ultrasonography (US), 2D CEUS, and dynamic 3D CEUS (frequency range, 1-6 MHz; focusing ability, 2-25 cm in depth; mechanical index, 0.09). Dynamic 3D CEUS images were postprocessed with high-resolution intelligent tomographic technology. The sensitivity and specificity of the CEUS methods in differentiating benign and malignant liver tumors were compared, as were the vascular characteristics (including the number and spatial relationships of the tumor vessels, such as origin and continuity) of the tumors in the arterial phase.

RESULTS

The imaging methods did not significantly differ in their sensitivity and specificity for differentiating benign and malignant liver tumors (P > .05). Dynamic 3D CEUS was significantly better than 2D CEUS in revealing the vascular characteristics of the tumors (P < .05). The vascular morphologic characteristics of benign and malignant hepatic tumors in the arterial phase of dynamic 3D CEUS using intelligent tomographic technology differed significantly (P < .05).

CONCLUSIONS

Dynamic 3D CEUS of liver tumors provides a more intuitive and comprehensive view of the spatial relationships of their blood vessels, including their peripheral and internal distribution. The volume information obtained with dynamic 3D CEUS combined with intelligent tomographic technology can improve the US-based diagnosis of liver tumors and thus guide their treatment.

Uncommon neoplasms of the biliary tract: radiological findings

OBJECTIVE

To report our cancer centre experience in the biliary tumours incidence other than cholangiocellular-carcinoma, emphasizing the radiological features.

METHODS

197 patients with biliary disease undergoing Gd-EOB-DTPA-enhanced MRI were reviewed. Four radiologists evaluated retrospectively size, structure, anatomical site and signal intensity of lesions on MRI. Enhancement-pattern during the arterial-, portal- and late-phase on ultrasound, CT and MR study was assessed as well as the enhancement pattern during the hepatobiliary-phase on MRI.

RESULTS

23 patients were selected. The lesion was intraductal in 5 cases, periductal in 14 and intrahepatic in 4. 16 lesions were solid, 5 uniloculated cystic and 2 complex cystic. In five patients the lesion was simple cyst, with a signal intensity in T₁ weighted (T1W) and T₂ weighted (T2W) similar to the gallbladder. In two patients with complex cystic lesion, the solid component was heterogeneously hypointense in T₁ W, hyperintense in T₂ W with a restricted diffusion. The solid component showed heterogeneous contrast-enhancement on CT, MR and ultrasound. The tumour was intrahepatic in two patients, with signal hypointense in T₁ W and hyperintense in T₂ W. Diffusion was restricted. The lesions showed heterogeneous contrast-enhancement. The periductal lesions were hypointense in T₁ W, hyperintense in T₂ W with restricted diffusion. The lesion showed progressive contrast-enhancement. Peribiliary melanoma was hyperintense in T₁ W, hyperintense in T₂ W with restricted diffusion and progressively contrast-enhanced.

CONCLUSION

Biliary tumours can have a wide spectrum of radiologic appearances and consequently represent a diagnostic challenge for the radiologist. Advances in knowledge: MRI is the technique of choice in diagnosing biliary tumours, including rare (non-CCC) tumours.

Diagnostic accuracy of magnetic resonance, computed tomography and contrast enhanced ultrasound in radiological multimodality assessment of peribiliary liver metastases

PURPOSE

We compared diagnostic performance of Magnetic Resonance (MR), Computed Tomography (CT) and Ultrasound (US) with (CEUS) and without contrast medium to identify peribiliary metastasis.

METHODS

We identified 35 subjects with histological proven peribiliary metastases who underwent CEUS, CT and MR study. Four radiologists evaluated the presence of peribiliary lesions, using a 4-point confidence scale. Echogenicity, density and T1-Weigthed (T1-W), T2-W and Diffusion Weighted Imaging (DWI) signal intensity as well as the enhancement pattern during contrast studies on CEUS, CT and MR so as hepatobiliary-phase on MRI was assessed.

RESULTS

All lesions were detected by MR. CT detected 8 lesions, while US/CEUS detected one lesion. According to the site of the lesion, respect to the bile duct and hepatic parenchyma: 19 (54.3%) were periductal, 15 (42.8%) were intra-periductal and 1 (2.8%) was periductal-intrahepatic. According to the confidence scale MRI had the best diagnostic performance to assess the lesion. CT obtained lower diagnostic performance. There was no significant difference in MR signal intensity and contrast enhancement among all metastases (p>0.05). There was no significant difference in CT density and contrast enhancement among all metastases (p>0.05).

CONCLUSIONS

MRI is the method of choice for biliary tract tumors but it does not allow a correct differential diagnosis among different histological types of metastasis. The presence of biliary tree dilatation without hepatic lesions on CT and US/CEUS study may be an indirect sign of peribiliary metastases and for this reason the patient should be evaluated by MRI.

Detection of liver metastases in cancer patients with geographic fatty infiltration of the liver: the added value of contrast-enhanced sonography

Purpose

The aim of this study is to assess the role of contrast-enhanced ultrasonography (CEUS) in the detection of liver metastases in cancer patients with geographic liver fatty deposition on greyscale ultrasonography (US).

Methods

Thirty-seven consecutive cancer patients (24 women and 13 men; age, 33 to 80 years; mean, 58.1 years) with geographic liver fatty deposition, but without any detectable focal liver lesion on greyscale US, underwent sulphur hexafluoride-enhanced US. Two readers reported by consensus the presence, size, and location of any detected lesion. All patients underwent magnetic resonance imaging (MRI) as a confirmatory study. Sensitivity, specificity, positive and negative predictive values (PPV and NPV), and accuracy were calculated.

Results

Seven focal liver lesions (size, 4 to 10 mm; mean, 6.1 mm) were detected in 4/37 patients (10.8%): four metastases (size, 5 to 10 mm; mean, 6.7 mm) were detected both by CEUS and MRI, with one hemangioma and two cysts (size range, 4 to 6 mm; mean, 5.3 mm) detected by MRI only. In 1/37 patients (2.7%), CEUS misdiagnosed geographic fatty change as three metastases. In 32/37 patients (86.5%), no lesions were detected. Sensitivity, specificity, PPV, NPV, and accuracy of CEUS were 100% (95% confidence Interval [CI], 1.000 to 1.000), 97.1% (95% CI, 0.914 to 1.027), 75%, 100%, and 97.3%, respectively. No statistically significant differences were found between CEUS and MRI in the detection of focal liver lesions (P=0.480), whereas both of them performed better than baseline US (P<0.001).

Conclusion

CEUS improves the detection of liver metastases in cancer patients with geographic liver fatty deposition on greyscale US.

Contrast-Enhanced Ultrasound in Focal Liver Lesions: Where Do We Stand?

Contrast-enhanced ultrasound (CEUS) represents a significant breakthrough in sonography, and it is being increasingly used for the evaluation of focal liver lesions (FLLs). Currently, CEUS is included as a part of the suggested diagnostic workup of FLLs, resulting in a better patient management and delivering cost-effective therapy. After a brief technical note, contrast-enhancement patterns of different types of benign and malignant FLLs, along with hepatic pseudolesions, are described and discussed based on our experience and literature data. At the same time, the most recent concepts and the use of CEUS in different clinical settings are presented.

ESMO consensus guidelines for the management of patients with metastatic colorectal cancer

Colorectal cancer (CRC) is one of the most common malignancies in Western countries. Over the last 20 years, and the last decade in particular, the clinical outcome for patients with metastatic CRC (mCRC) has improved greatly due not only to an increase in the number of patients being referred for and undergoing surgical resection of their localised metastatic disease but also to a more strategic approach to the delivery of systemic therapy and an expansion in the use of ablative techniques. This reflects the increase in the number of patients that are being managed within a multidisciplinary team environment and specialist cancer centres, and the emergence over the same time period not only of improved imaging techniques but also prognostic and predictive molecular markers. Treatment decisions for patients with mCRC must be evidence-based. Thus, these ESMO consensus guidelines have been developed based on the current available evidence to provide a series of evidence-based recommendations to assist in the treatment and management of patients with mCRC in this rapidly evolving treatment setting.

Cost evaluation of gadoxetic acid-enhanced magnetic resonance imaging in the diagnosis of colorectal-cancer metastasis in the liver: Results from the VALUE Trial

OBJECTIVES

To assess the costs of diagnostic workup and surgery of three strategies for patients with colorectal cancer liver-metastases (CRCLM): gadoxetic-acid-enhanced MRI (Gd-EOB-DTPA-MRI), MRI with extracellular contrast-media (ECCM-MRI) or contrast-enhanced MDCT (CE-MDCT).

METHODS

The within-trial cost evaluation was modelled as a decision-tree to calculate the cost of diagnosis and surgery. The model used clinical outcomes and resource utilization data from a prospective randomized multicentre study. Analyses were performed for the 354-patient safety population from eight participating countries.

RESULTS

The diagnostic workup cost using Gd-EOB-DTPA-MRI upfront resulted in savings compared to ECCM-MRI in all countries except Thailand (difference <2 %). Compared to CE-MDCT, initial imaging with Gd-EOB-DTPA-MRI was less costly in all countries except Korea and Spain (differences 4 and 8 %, respectively). Significantly more patients in the Gd-EOB-DTPA-MRI group were eligible for surgery (39.3 % (48/122) vs. 31.0 % (36/116) and 26.7 % (31/116) for ECCM-MRI and CE-MDCT, respectively), allowing more patients to undergo potentially curative surgery, but resulting in higher treatment costs for the strategy starting with Gd-EOB-DTPA-MRI.

CONCLUSIONS

The benefits of Gd-EOB-DTPA-MRI due to less additional imaging and similar diagnostic workup costs in the three groups suggest that Gd-EOB-DTPA-MRI should be the preferred initial imaging procedure to evaluate hepatic resectability in patients with CRCLM.

KEY POINTS

• Diagnostic imaging cost to evaluate resectability was similar among the groups • Cost for imaging was rather small compared to the cost of surgery • Significantly more patients in the Gd-EOB-DTPA-MRI arm were eligible for surgery • Gd-EOB-DTPA-MRI is recommended for evaluating hepatic resectability in patients with CRCLM.

Activity-based cost analysis of contrast-enhanced ultrasonography (CEUS) related to the diagnostic impact in focal liver lesion characterisation

PURPOSE

This study was done to assess the clinical-diagnostic impact and cost of contrast-enhanced ultrasound (CEUS) versus computed tomography (CT) and magnetic resonance (MR) imaging in the characterisation of focal liver lesions.

MATERIALS AND METHODS

CEUS with sulphur hexafluoride-filled microbubbles (SonoVue bolus 2.4 ml) was performed in 157 patients with 160 focal liver lesions identified by other diagnostic techniques. CEUS images were obtained during the arterial (15 to 35 s from contrast injection), portal venous (40 to 70 s) and late phase (up to 300 s from microbubble injection). Contrast-enhanced CT was performed with a 64-row multidetector CT. MRI was performed before and after administration of the liver-specific contrast agent gadobenate dimeglumine (Gd-BOPTA). A patient-by-patient activity-based cost analysis was performed.

RESULTS

CEUS led to a change in the diagnostic workup in 131/157 patients (83.4 %) and in the therapeutic workup in 93/157 patients (59.2 %). CEUS allowed for the final diagnosis to be established in 133/157 patients (84.7 %). The full cost of CEUS was lower than that of contrast-enhanced CT and MR imaging.

CONCLUSIONS

CEUS determined a change in the diagnostic and therapeutic workup in the characterisation of focal liver lesions and reduced the full costs of the diagnostic process.

MAIN MESSAGES

• CEUS allows a correct diagnosis in more than 80 % of focal liver lesions. • CEUS has a significant impact on the diagnosis of focal liver lesions. • CEUS examination of focal liver lesions reduces total costs. • Dynamic MR with hepato-specific contrast medium remains the reference standard for lesion characterisation. • CEUS is low-cost, versatile and accurate in the characterisation of focal liver lesions.

Latest developments in the imaging of fibrotic liver disease

According to the World Health Organization, liver cirrhosis accounted for 1.8% of all deaths in Europe, causing about 170,000 deaths per year. Approximately 29 million persons in the EU suffer from chronic liver disease and this trend is on the rise. Liver disease is the EU's fifth most common cause of death accounting for at least one in six deaths. Early detection and monitoring of fibrosis has the potential to direct management of these chronic liver diseases and avert morbidity and mortality. Although the available techniques are in their infancy and the very early stages of fibrosis are difficult to detect, there have been significant advances in imaging over the last decade that has resulted in the use of these new imaging techniques being introduced into the patient pathway. This review explores the accuracies of these imaging techniques, their role in the management of patients, and the potential for the future.

Diagnostic performance of contrast-enhanced sonography and acoustic radiation force impulse imaging in solid liver lesions

OBJECTIVES

The purpose of this study was to evaluate the diagnostic performance of contrast-enhanced sonography and acoustic radiation force impulse imaging (ARFI) in differential diagnosis of benign and malignant liver lesions.

METHODS

A total of 156 patients with liver lesions were included in the study. The images from conventional sonography and contrast-enhanced sonography and the shear wave velocity values of the liver lesions were obtained. The diagnostic performance of conventional sonography, contrast-enhanced sonography, and ARFI was assessed by using pathologic examination (needle biopsy or surgery) or clinical imaging inspection as the reference standard.

RESULTS

The sensitivity and specificity of conventional sonography for malignant liver lesions were 57.1% and 43.1%, respectively, and the sensitivity and specificity of ARFI were 81.3% and 74.1%. When using contrast-enhanced sonography for the diagnosis of malignant liver lesions, the sensitivity and specificity were 92.9% and 89.7%. The sensitivity and specificity of contrast-enhanced sonography were significantly higher than those of ARFI and conventional sonography (P < .05).

CONCLUSIONS

The differential diagnostic performance of contrast-enhanced sonography is most predictive of malignant liver lesions. Contrast-enhanced sonography and ARFI have complementary effects in the differential diagnosis of benign and malignant liver lesions.

Contrast-enhanced ultrasound in the preoperative, intraoperative and postoperative assessment of liver lesions

The use of contrast agents (CA) with liver ultrasound (US) has gained recently an established role for the diagnosis of various hepatic diseases due to their safety, high versatility and low costs (contrast-enhanced ultrasound: CEUS). The purpose of this review is to provide a state-of-the-art summary of the available evidence for their use in the characterization of focal liver lesions. A published work search was conducted for all preclinical and clinical studies involving CA on hepatic US imaging. CEUS increases the sensitivity for lesion detection and the specificity to differentiate between benign and malignant diseases due to the enhanced visualization of the tumor microcirculation. Results achieved seem at least equivalent to those of spiral computed tomography or magnetic resonance imaging. The association of CA with intraoperative ultrasound has changed the surgical approach in 25% of patients and guarantees complete ablations by a single session in most of them. CEUS provides detailed information about tumor vasculature, improves the preoperative characterization and therefore the therapeutic strategy, and can evaluate the intraoperative completeness of the ablation.

Contrast-Enhanced Ultrasound for the differentiation of benign and malignant focal liver lesions: a meta-analysis

BACKGROUND

International guidelines of Ultrasound recommend the performance of contrast-enhanced ultrasound (CEUS) as the first method of choice after conventional ultrasound for the diagnostic work-up of focal liver lesions. However, these recommendations are based on the results of multiple single studies and only few large multicentre studies.

AIMS

The rationale of the present systematic review and meta-analysis was to assess the overall sensitivity and specificity of CEUS for the diagnosis of malignant liver lesions.

METHODS

Literature databases were searched up to March 2012. Inclusion criteria were evaluation of CEUS, assessment of sensitivity and specificity of CEUS for the diagnosis of malignant liver lesions. The meta-analysis was performed using the random-effects model based on the DerSimonian Laird method. Quality analyses were carried out to assess sources of heterogeneity.

RESULTS

A total of 45 studies with 8147 focal liver lesions were included in the analysis. Overall sensitivity and specificity of CEUS for the diagnosis of malignant liver lesions was 93% (95%-CI: 91-95%) and 90% (95%-CI: 88-92%) respectively. Significant heterogeneity was found between studies. However, subanalysis revealed no significant difference when evaluating studies using histology for all liver lesions, when comparing high-quality and low-quality studies, and blinded vs non-blinded studies.

CONCLUSION

The results of this meta-analysis support the international recommendations on CEUS for the diagnostic work-up of focal liver lesions selecting patients who need further diagnostics.

The oncosurgery approach to managing liver metastases from colorectal cancer: a multidisciplinary international consensus

An international panel of multidisciplinary experts convened to develop recommendations for the management of patients with liver metastases from colorectal cancer (CRC). The aim was to address the main issues facing the CRC hepatobiliary multidisciplinary team (MDT) when managing such patients and to standardize the treatment patients receive in different centers. Based on current evidence, the group agreed on a number of issues including the following: (a) the primary aim of treatment is achieving a long disease-free survival (DFS) interval following resection; (b) assessment of resectability should be performed with high-quality cross-sectional imaging, staging the liver with magnetic resonance imaging and/or abdominal computed tomography (CT), depending on local expertise, staging extrahepatic disease with thoracic and pelvic CT, and, in selected cases, fluorodeoxyglucose positron emission tomography with ultrasound (preferably contrast-enhanced ultrasound) for intraoperative staging; (c) optimal first-line chemotherapy-doublet or triplet chemotherapy regimens combined with targeted therapy-is advisable in potentially resectable patients; (d) in this situation, at least four courses of first-line chemotherapy should be given, with assessment of tumor response every 2 months; (e) response assessed by the Response Evaluation Criteria in Solid Tumors (conventional chemotherapy) or nonsize-based morphological changes (antiangiogenic agents) is clearly correlated with outcome; no imaging technique is currently able to accurately diagnose complete pathological response but high-quality imaging is crucial for patient management; (f) the duration of chemotherapy should be as short as possible and resection achieved as soon as technically possible in the absence of tumor progression; (g) the number of metastases or patient age should not be an absolute contraindication to surgery combined with chemotherapy; (h) for synchronous metastases, it is not advisable to undertake major hepatic surgery during surgery for removal of the primary CRC; the reverse surgical approach (liver first) produces as good an outcome as the conventional approach in selected cases; (i) for patients with resectable liver metastases from CRC, perioperative chemotherapy may be associated with a modestly better DFS outcome; and (j) whether initially resectable or unresectable, cure or at least a long survival duration is possible after complete resection of the metastases, and MDT treatment is essential for improving clinical and survival outcomes. The group proposed a new system to classify initial unresectability based on technical and oncological contraindications.

Splenic hemangiomas: contrast-enhanced sonographic findings

OBJECTIVES

The purpose of this study was to illustrate the baseline appearance and enhancement patterns of splenic hemangiomas on contrast-enhanced sonography.

METHODS

Two experienced radiologists retrospectively reviewed by consensus baseline and contrast-enhanced sonographic examinations of 27 patients (14 women and 13 men; mean age, 58.7 years) with 27 splenic hemangiomas (mean size, 2 cm) confirmed by splenectomy, biopsy, computed tomography, and magnetic resonance imaging and follow-up.

RESULTS

On baseline sonography, 77.8% of the lesions showed a homogeneous echo texture that was mainly hyperechoic. Color Doppler imaging did not show any signal in 81.5% of the cases. After contrast agent injection, 59.2% of the splenic hemangiomas showed different degrees of contrast enhancement in the arterial phase followed by isoenhancement in the late parenchymal phase. Among these, 2 hemangiomas showed peripheral globular enhancement in the arterial phase, followed by progressive centripetal fill-in. In 29.6% of the cases, some degree of contrast enhancement was appreciable, but the hemangiomas remained substantially hypoechoic throughout the contrast-enhanced sonographic examinations, whereas in 11.1%, the combination of contrast enhancement in the arterial phase followed by wash-out in the late parenchymal phase was evident.

CONCLUSIONS

Isoechogenicity to spleen parenchyma in all phases is the most frequent typical enhancement pattern of splenic hemangiomas observed on contrast-enhanced sonography. Nevertheless, these lesions may show atypical contrast enhancement patterns; therefore, further assessment with cross-sectional techniques is needed.

Contrast-enhanced ultrasound features of hepatocellular carcinoma of different sizes

AIM: To analyze the contrast-enhanced ultrasound (CEUS) features of hepatocellular carcinoma (HCC) of different sizes.

METHODS: A total of 75 consecutive patients with 90 HCC lesions were enrolled. HCC was examined by CEUS and confirmed by surgery and pathology. These patients were divided into two groups according to the maximum diameter of the lesion: small HCC (SHCC) group (diameter ≤3 cm) and large HCC (LHCC) group (>3 cm). The CEUS characteristics of HCC of different sizes were analyzed retrospectively.

RESULTS: Among 90 lesions, 39 were small HCC (SHCC) and 51 were large HCC (LHCC). During the arterial phase, all the 39 lesions in the SHCC group exhibited hyperenhancement, of which 37 (94.9%) were homogeneously and 2 (5.1%) were inhomogeneously enhanced. Comparatively, all the 51 lesions in the LHCC group exhibited hyperenhancement, of them 27 (52.9%) appeared as homogeneous enhancement, 21 (41.2%) as inhomogeneous enhancement and 6 (6%) as atypical patterns. The enhancement patterns had significant difference during the arterial phase between the two groups (P < 0.05). During the portal phase, 10 (25.6%) lesions were isoechoic and 29 (74.4%) were hypoechoic in the SHCC group, while 7 (13.7%) lesions were hyperechoic, 2 were isoechoic (3.9%), and 42 (82.4%) were hypoechoic in the LHCC group. A significant difference was also noted in enhancement patterns during the portal phase between the two groups (P < 0.05). During the late phase, hypoenhancement was visualized in all the SHCC lesions, while in the LHCC group, hypoenhancement was visualized in 50 (98%) lesions and isoenhancement in 1 (2%) lesion. No significant difference was observed in enhancement patterns during the late phase between the two groups.

CONCLUSION: Our study shows that the enhancement manifestations of HCC are related to lesion size. During the arterial phase, most SHCC lesions show homogeneous enhancement, while inhomogeneous enhancement patterns appear mostly in LHCC lesions. During the portal and late phases, SHCC lesions may be washed out earlier than LHCC ones.

Incidence of new foci of hepatocellular carcinoma after radiofrequency ablation: role of multidetector CT

PURPOSE

The authors sought to assess the incidence of new foci of hepatocellular carcinoma (HCC) using multidetector computed tomography (MDCT) in patients treated with radiofrequency ablation (RFA).

MATERIALS AND METHODS

Two readers retrospectively reviewed by consensus the follow-up MDCT studies of 125 patients (88 men and 37 women; mean age 68 years) with 141 HCCs (size 1-5.2 cm; mean 2.2 cm) treated with RFA. MDCT follow-up was performed at 1 and 3 months and every 6-12 months thereafter. Reviewers assessed: (1) the presence of new HCC foci in the same liver segment or in a different segment; (2) complete or incomplete tumour ablation; (3) tumour progression.

RESULTS

A total of 113 new HCCs (size 0.7-4.8 cm; mean 1.7 cm) were detected in 69/125 (55.2%) patients (mean follow-up 30.38±19.14 months). Of these, 86 (76.1%) new HCCs were multiple (p<0.0001), and 92 (81.4%) occurred in a different segment from that of the treated HCC (p<0.0001). New HCCs were observed in the first 12 months, between 12 and 24 months and after 24 months in 31/69 (44.9%), 24/69 (34.8%) and 14/69 (20.3%) patients, respectively (p=0.175). Mean diseasefree interval was 16.1±16.31 (range 1-52) months. Complete tumour ablation was achieved in 132/141 (93.6%) treated HCCs, and tumour progression occurred in 29/141 (20.6%) cases.

CONCLUSIONS

In patients with RFA-treated HCCs, MDCT follow-up revealed a high incidence of new HCCs, even after 1 year of follow-up. The new foci tended to be multiple and located in a liver segment different from that of the previously treated nodules.

Diagnostic value of contrast-enhanced ultrasound, computed tomography and magnetic resonance imaging for focal liver lesions: a meta-analysis

The diagnostic performance of contrast-enhanced ultrasound (CEUS), contrast-enhanced computed tomography (CECT) and contrast-enhanced magnetic resonance imaging (CEMRI) was determined in patients with focal liver lesions (FLLs) in a meta-analysis. Meta-Disc version 1.4 was used to describe and calculate sensitivity, specificity, summary receiver operating characteristic (SROC) curves and area under the curve (AUC). In the 25 included studies, the pooled estimate of CEUS studies for sensitivity, specificity and diagnostic odds ratio (DOR) was 87% (95% CI 85-88), 89% (95% CI 87-91) and 78.84 (95% CI 29.40-211.40), respectively. Sensitivity, specificity and DOR were 86% (95% CI 84-88), 82% (95% CI 77-86) and 26.34 (95% CI 8.32-83.39), respectively, for the CECT studies. Sensitivity, specificity and DOR were 85% (95% CI 82-88), 87% (95% CI 83-91) and 48.37 (95% CI 15.87-147.45), respectively, for the CEMRI studies. SROC analysis indicated that the diagnostic value of CEUS for FLLs is not significantly different from that of CECT and CEMRI.

Source and clinical motivation of orders for contrast-enhanced sonography (CEUS) of the liver: A prospective single-center survey

Contrast-enhanced sonography (CEUS) has become a routine part of diagnostic imaging of the liver. Its possibilities, limitations, and indications have been defined in adequately large clinical series and in guidelines and recommendations. We prospectively evaluated physicians' orders for hepatic CEUS received in the radiology department of a large oncology center in Naples, Italy from May 2009 to April 2010. Radiologists performing the CEUS examinations filled out a form that included patient demography, source and type of patient referral, and clinical indications for the examination. During the study period, 564 patients aged 17-86 years (mean, 58 years) were referred to our department for CEUS liver studies (total: 644; 491 outpatient studies, 153 inpatient studies). This included 4 examinations that were ordered by the patient's physician but not performed by our staff. The majority of the CEUS examinations (n = 583; 90.5%) were regularly scheduled procedures ordered by clinical specialists from our center (77.3%) or other centers (11.8%); by general practitioners (on their own initiative) (0.8%); or by other figures (0.6%). The remaining 61 examinations (9.5%) were unscheduled procedures done on the initiative of a radiologist following conventional sonography (US). Fewer than half (47.8%) of the examinations were requested as first-line assessments. The others were ordered to clarify inconclusive findings generated by conventional US (30%) or by a more sophisticated imaging study (CT, MRI, PET) (16.1%) or to resolve discrepancies between CT, MRI, and/or PET findings (6%). CEUS is a relatively noninvasive, low-cost imaging study that is simple to perform and requires no particular patient preparation. This may explain its increasing use to clarify doubts raised by conventional US and other more sophisticated imaging studies.