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

New microvascular ultrasound techniques: abdominal applications

Microvascular ultrasound (MVUS) is a new ultrasound technique that allows the detection of slow-velocity flow, providing the visualization of the blood flow in small vessels without the need of intravenous contrast agent administration. This technology has been integrated in the most recent ultrasound equipment and applied for the assessment of vascularization. Compared to conventional color Doppler and power Doppler imaging, MVUS provides higher capability to detect intralesional flow. A growing number of studies explored the potential applications in hepatobiliary, genitourinary, and vascular pathologies. Different flow patterns can be observed in hepatic and renal focal lesions providing information on tumor vascularity and improving the differential diagnosis. This article aims to provide a detailed review on the current evidences and applications of MVUS in abdominal imaging

Breast dynamic contrast-enhanced-magnetic resonance imaging and radiomics: State of art

Breast cancer represents the most common malignancy in women, being one of the most frequent cause of cancer-related mortality. Ultrasound, mammography, and magnetic resonance imaging (MRI) play a pivotal role in the diagnosis of breast lesions, with different levels of accuracy. Particularly, dynamic contrast-enhanced MRI has shown high diagnostic value in detecting multifocal, multicentric, or contralateral breast cancers. Radiomics is emerging as a promising tool for quantitative tumor evaluation, allowing the extraction of additional quantitative data from radiological imaging acquired with different modalities. Radiomics analysis may provide novel information through the quantification of lesions heterogeneity, that may be relevant in clinical practice for the characterization of breast lesions, prediction of tumor response to systemic therapies and evaluation of prognosis in patients with breast cancers. Several published studies have explored the value of radiomics with good-to-excellent diagnostic and prognostic performances for the evaluation of breast lesions. Particularly, the integrations of radiomics data with other clinical and histopathological parameters have demonstrated to improve the prediction of tumor aggressiveness with high accuracy and provided precise models that will help to guide clinical decisions and patients management. The purpose of this article in to describe the current application of radiomics in breast dynamic contrast-enhanced MRI

New frontiers in liver ultrasound: From mono to multi parametricity

Modern liver ultrasonography (US) has become a "one-stop shop " able to provide not only anatomic and morphologic but also functional information about vascularity, stiffness and other various liver tissue properties. Modern US techniques allow a quantitative assessment of various liver diseases. US scanning is no more limited to the visualized plane, but three-dimensional, volumetric acquisition and consequent post-processing are also possible. Further, US scan can be consistently merged and visualized in real time with Computed Tomography and Magnetic Resonance Imaging examinations. Effective and safe microbubble-based contrast agents allow a real time, dynamic study of contrast kinetic for the detection and characterization of focal liver lesions. Ultrasound can be used to guide loco-regional treatment of liver malignancies and to assess tumoral response either to interventional procedures or medical therapies. Microbubbles may also carry and deliver drugs under ultrasound exposure. US plays a crucial role in diagnosing, treating and monitoring focal and diffuse liver disease. On the basis of personal experience and literature data, this paper is aimed to review the main topics involving recent advances in the field of liver ultrasound

Focal Pancreatic Lesions: Role of Contrast-Enhanced Ultrasonography

The introduction of contrast-enhanced ultrasonography (CEUS) has led to a significant improvement in the diagnostic accuracy of ultrasound in the characterization of a pancreatic mass. CEUS, by using a blood pool contrast agent, can provide dynamic information concerning macro- and micro-circulation of focal lesions and of normal parenchyma, without the use of ionizing radiation. On the basis of personal experience and literature data, the purpose of this article is to describe and discuss CEUS imaging findings of the main solid and cystic pancreatic lesions with varying prevalence

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

Multiparametric MRI and Radiomics in Prostate Cancer: A Review of the Current Literature

Prostate cancer (PCa) represents the fourth most common cancer and the fifth leading cause of cancer death of men worldwide. Multiparametric MRI (mp-MRI) has high sensitivity and specificity in the detection of PCa, and it is currently the most widely used imaging technique for tumor localization and cancer staging. mp-MRI plays a key role in risk stratification of naive patients, in active surveillance for low-risk patients, and in monitoring recurrence after definitive therapy. Radiomics is an emerging and promising tool which allows a quantitative tumor evaluation from radiological images via conversion of digital images into mineable high-dimensional data. The purpose of radiomics is to increase the features available to detect PCa, to avoid unnecessary biopsies, to define tumor aggressiveness, and to monitor post-treatment recurrence of PCa. The integration of radiomics data, including different imaging modalities (such as PET-CT) and other clinical and histopathological data, could improve the prediction of tumor aggressiveness as well as guide clinical decisions and patient management. The purpose of this review is to describe the current research applications of radiomics in PCa on MR images

Focal nodular hyperplasia: a weight-based, intraindividual comparison of gadobenate dimeglumine and gadoxetate disodium-enhanced MRI

PURPOSE: We aimed to qualitatively and quantitatively compare the enhancement pattern of focal nodular hyperplasia after gadobenate dimeglumine and gadoxetate disodium injection in the same patient. METHODS: 1.5 T magnetic resonance imaging (MRI) examinations of 16 patients with 21 focal nodular hyperplasias studied after the injection of both contrast media were evaluated. Both MRI studies were performed in all patients. A qualitative analysis was performed evaluating each lesion in all phases. For quantitative analysis we calculated signal intensity ratio, lesion-to-liver contrast ratio and liver parenchyma signal intensity gain on hepatobiliary phase. Statistical analysis was performed with the Wilcoxon sign-rank test for clustered paired data and the McNemar test for paired frequencies. A P value < 0.05 was considered statistically significant. RESULTS: At qualitative analysis no statistically significant differences were evident during any of the contrast-enhanced phases. Signal intensity ratio (P = 0.048), lesion-to-liver contrast ratio (P = 0.032) and liver parenchyma signal intensity gain (P = 0.012) were significantly higher on hepatobiliary phase after gadoxetate disodium injection. CONCLUSION: There were no significant differences in the MRI findings of focal nodular hyperplasia after the injection of a weight-based dose of either gadobenate dimeglumine or gadoxetate disodium

Advances in liver US, CT, and MRI: moving toward the future

Over the past two decades, the epidemiology of chronic liver disease has changed with an increase in the prevalence of nonalcoholic fatty liver disease in parallel to the advent of curative treatments for hepatitis C. Recent developments provided new tools for diagnosis and monitoring of liver diseases based on ultrasound (US), computed tomography (CT), and magnetic resonance imaging (MRI), as applied for assessing steatosis, fibrosis, and focal lesions. This narrative review aims to discuss the emerging approaches for qualitative and quantitative liver imaging, focusing on those expected to become adopted in clinical practice in the next 5 to 10 years. While radiomics is an emerging tool for many of these applications, dedicated techniques have been investigated for US (controlled attenuation parameter, backscatter coefficient, elastography methods such as point shear wave elastography [pSWE] and transient elastography [TE], novel Doppler techniques, and three-dimensional contrast-enhanced ultrasound [3D-CEUS]), CT (dual-energy, spectral photon counting, extracellular volume fraction, perfusion, and surface nodularity), and MRI (proton density fat fraction [PDFF], elastography [MRE], contrast enhancement index, relative enhancement, T1 mapping on the hepatobiliary phase, perfusion). Concurrently, the advent of abbreviated MRI protocols will help fulfill an increasing number of examination requests in an era of healthcare resource constraints

Characterisation of indeterminate focal breast lesions on grey-scale ultrasound: role of ultrasound elastography.

PURPOSE: This study was undertaken to evaluate the role of ultrasound (US) elastography in characterising focal breast lesions classified as indeterminate on B-mode US. MATERIALS AND METHODS: Eighty-four focal breast lesions, 64 benign and 20 malignant (mean diameter, 15.1 mm), detected but not characterised on B-mode US in 72 women, Breast Imaging Reporting and Data System (BI-RADS) US category 3 (n=56) or category 4 (n=28), were studied with US elastography and classified in consensus by two radiologists according to a five-point colour scale. Sensitivity, specificity and positive and negative predictive values (PPV and NPV) of US elastography compared with conventional US were calculated in relation to microhistology (n=67) and cytology (n=17), which were used as the reference standard. RESULTS: A total of 65/84 (77.4%) lesions were correctly classified as benign or malignant using US elastography, whereas the remaining 19/84 (22.6%) were incorrectly assessed. There were no statistically significant differences between US elastography and B-mode US with regard to sensitivity (70% vs. 68.4%), specificity (79.6% vs. 78.5%), PPV (51.8% vs. 48.1%) and NPV 89% vs. 89.5% (p>0.5). By contrast, a statistically significant difference was noted in the evaluation of BI-RADS 3 lesions, in which US elastography had 50% sensitivity, 86% specificity, 30% PPV and 93.5% NPV compared with BI-RADS 4 lesions (78.6%, 57.1%, 64.7% and 72.7%) (p<0.5). CONCLUSIONS: The high NPV of US elastography may help reduce the use of biopsy in BI-RADS 3 lesions, but its low PPV in BI-RADS 4 lesions does not allow avoidance of biopsy on the basis of the US elastographic score alone in this group of lesions